$ambc 2020 Q4 10-K

Concept	2020 Q4	2020	2019 Q4
Revenue	$53.00M	$156.0M	$42.00M
YoY Change	26.19%	-68.55%	13.51%
Cost Of Revenue
YoY Change
Gross Profit
YoY Change
Gross Profit Margin
Selling, General & Admin		$4.000M	$800.0K
YoY Change		-42.86%
% of Gross Profit
Research & Development
YoY Change
% of Gross Profit
Depreciation & Amortization	$17.00M	$58.00M	$14.70M
YoY Change	15.65%	-80.34%	-49.66%
% of Gross Profit
Operating Expenses	$50.00M	$374.0M	$136.4M
YoY Change	-63.34%	-9.22%	1605.0%
Operating Profit
YoY Change
Interest Expense	-$42.00M	-$226.0M	-$66.70M
YoY Change	-37.03%	-15.99%	0.91%
% of Operating Profit
Other Income/Expense, Net
YoY Change
Pretax Income	-$12.00M	-$441.0M	-$111.0M
YoY Change	-89.19%	153.45%	404.55%
Income Tax	$2.000M	-$3.000M	-$1.300M
% Of Pretax Income
Net Earnings	-$14.00M	-$437.0M	-$110.0M
YoY Change	-87.27%	102.31%	450.0%
Net Earnings / Revenue	-26.42%	-280.13%	-261.9%
Basic Earnings Per Share	-$0.31	-$9.47	-$2.40
Diluted Earnings Per Share	-$0.31	-$9.47	-$2.40
COMMON SHARES
Basic Shares Outstanding	45.81M shares	46.15M shares	45.55M shares
Diluted Shares Outstanding		46.15M shares

Concept	2020 Q4	2020	2019 Q4
SHORT-TERM ASSETS
Cash & Short-Term Investments
YoY Change
Cash & Equivalents	$20.00M	$20.00M	$24.00M
Short-Term Investments
Other Short-Term Assets
YoY Change
Inventory
Prepaid Expenses
Receivables
Other Receivables
Total Short-Term Assets
YoY Change
LONG-TERM ASSETS
Property, Plant & Equipment	$25.00M	$25.00M	$25.00M
YoY Change	0.0%	0.0%
Goodwill	$46.00M
YoY Change
Intangibles	$409.0M		$427.0M
YoY Change	-4.22%		-40.61%
Long-Term Investments	$51.00M	$9.896B	$46.00M
YoY Change	10.87%	-1.25%	15.0%
Other Assets	$15.00M	$15.00M	$57.00M
YoY Change	-73.68%	-73.68%	185.0%
Total Long-Term Assets
YoY Change
TOTAL ASSETS
Total Short-Term Assets
Total Long-Term Assets
Total Assets	$13.22B	$13.22B	$13.32B
YoY Change	-0.75%	-0.75%	-8.7%
SHORT-TERM LIABILITIES
YoY Change
Accounts Payable
YoY Change
Accrued Expenses	$547.0M	$547.0M	$471.0M
YoY Change	16.14%	16.14%	25.27%
Deferred Revenue
YoY Change
Short-Term Debt	$0.00	$0.00	$0.00
YoY Change
Long-Term Debt Due
YoY Change
Total Short-Term Liabilities	$553.0M	$553.0M	$471.0M
YoY Change	17.41%	17.41%	24.6%
LONG-TERM LIABILITIES
Long-Term Debt	$7.232B	$7.232B	$7.376B
YoY Change	-1.95%	-1.95%	-10.03%
Other Long-Term Liabilities	$2.023B	$2.023B	$1.810B
YoY Change	11.77%	11.77%	-2.22%
Total Long-Term Liabilities	$9.255B	$9.255B	$9.186B
YoY Change	0.75%	0.75%	-8.59%
TOTAL LIABILITIES
Total Short-Term Liabilities	$553.0M	$553.0M	$471.0M
Total Long-Term Liabilities	$9.255B	$9.255B	$9.186B
Total Liabilities	$12.07B	$12.14B	$11.78B
YoY Change	2.47%	2.51%	-9.05%
SHAREHOLDERS EQUITY
Retained Earnings	$759.0M		$1.203B
YoY Change	-36.91%		-15.34%
Common Stock	$0.00		$0.00
YoY Change
Preferred Stock
YoY Change
Treasury Stock (at cost)	$1.000M		$0.00
YoY Change
Treasury Stock Shares	55.94K shares		16.34K shares
Shareholders Equity	$1.080B	$1.079B	$1.477B
YoY Change
Total Liabilities & Shareholders Equity	$13.22B	$13.22B	$13.32B
YoY Change	-0.75%	-0.75%	-8.7%

Concept	2020 Q4	2020	2019 Q4
OPERATING ACTIVITIES
Net Income	-$14.00M	-$437.0M	-$110.0M
YoY Change	-87.27%	102.31%	450.0%
Depreciation, Depletion And Amortization	$17.00M	$58.00M	$14.70M
YoY Change	15.65%	-80.34%	-49.66%
Cash From Operating Activities	-$8.000M	-$175.0M	-$14.80M
YoY Change	-45.95%	-43.73%	-88.2%
INVESTING ACTIVITIES
Capital Expenditures
YoY Change
Acquisitions		-$74.00M
YoY Change
Other Investing Activities	$36.00M	-$1.000M	$208.6M
YoY Change	-82.74%	-150.0%	-38.38%
Cash From Investing Activities	$36.00M	$432.0M	$208.6M
YoY Change	-82.74%	-56.8%	-38.38%
FINANCING ACTIVITIES
Cash Dividend Paid
YoY Change
Common Stock Issuance & Retirement, Net
YoY Change
Debt Paid & Issued, Net		$0.00
YoY Change
Cash From Financing Activities	-43.00M	-$303.0M	-180.4M
YoY Change	-76.16%	-56.15%	-1.69%
NET CHANGE
Cash From Operating Activities	-8.000M	-$175.0M	-14.80M
Cash From Investing Activities	36.00M	$432.0M	208.6M
Cash From Financing Activities	-43.00M	-$303.0M	-180.4M
Net Change In Cash	-15.00M	-$46.00M	13.40M
YoY Change	-211.94%	2200.0%	-54.73%
FREE CASH FLOW
Cash From Operating Activities	-$8.000M	-$175.0M	-$14.80M
Capital Expenditures
Free Cash Flow
YoY Change

Frame	Concept Type	Concept / XBRL Key	Value	Unit
CY2020	dei	Amendment Flag AmendmentFlag	false
CY2020	dei	Document Period End Date DocumentPeriodEndDate	2020-12-31
CY2020	dei	Document Fiscal Year Focus DocumentFiscalYearFocus	2020
CY2020	dei	Document Fiscal Period Focus DocumentFiscalPeriodFocus	FY
CY2020	dei	Entity Central Index Key EntityCentralIndexKey	0000874501
CY2020	dei	Current Fiscal Year End Date CurrentFiscalYearEndDate	--12-31
CY2020	dei	Entity Current Reporting Status EntityCurrentReportingStatus	Yes
CY2020	dei	Entity Filer Category EntityFilerCategory	Large Accelerated Filer
CY2020	dei	Entity Small Business EntitySmallBusiness	false
CY2020	dei	Entity Emerging Growth Company EntityEmergingGrowthCompany	false
CY2020	dei	Entity Shell Company EntityShellCompany	false
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	ambc	Impactof Amt Repealon Current Taxes ImpactofAMTRepealonCurrentTaxes	29581000	USD
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CY2020	dei	Document Type DocumentType	10-K
CY2020	dei	Document Annual Report DocumentAnnualReport	true
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CY2020	dei	Entity File Number EntityFileNumber	1-10777
CY2020	dei	Entity Registrant Name EntityRegistrantName	AMBAC FINANCIAL GROUP, INC.
CY2020	dei	Entity Incorporation State Country Code EntityIncorporationStateCountryCode	DE
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CY2020	dei	Entity Voluntary Filers EntityVoluntaryFilers	No
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CY2019	us-gaap	Comprehensive Income Net Of Tax Including Portion Attributable To Noncontrolling Interest ComprehensiveIncomeNetOfTaxIncludingPortionAttributableToNoncontrollingInterest	-125000000	USD
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CY2020	us-gaap	Comprehensive Income Net Of Tax Including Portion Attributable To Noncontrolling Interest ComprehensiveIncomeNetOfTaxIncludingPortionAttributableToNoncontrollingInterest	-400000000	USD
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CY2020	us-gaap	Noncontrolling Interest Increase From Subsidiary Equity Issuance NoncontrollingInterestIncreaseFromSubsidiaryEquityIssuance	7000000	USD
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CY2019	us-gaap	Allocated Share Based Compensation Expense AllocatedShareBasedCompensationExpense	12000000	USD
CY2019	us-gaap	Stock Issued During Period Value Share Based Compensation StockIssuedDuringPeriodValueShareBasedCompensation	-3000000	USD
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CY2017Q4	us-gaap	Stockholders Equity Including Portion Attributable To Noncontrolling Interest StockholdersEquityIncludingPortionAttributableToNoncontrollingInterest	1645000000	USD
CY2018	us-gaap	Comprehensive Income Net Of Tax Including Portion Attributable To Noncontrolling Interest ComprehensiveIncomeNetOfTaxIncludingPortionAttributableToNoncontrollingInterest	274000000	USD
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CY2018	us-gaap	Allocated Share Based Compensation Expense AllocatedShareBasedCompensationExpense	12000000	USD
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CY2019	us-gaap	Net Income Loss NetIncomeLoss	-216000000	USD
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CY2019	ambc	Amps Exchange Loss Basedon Carry Value AMPSExchangeLossBasedonCarryValue	0	USD
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CY2020	us-gaap	Profit Loss ProfitLoss	-437000000	USD
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CY2017Q4	us-gaap	Cash Cash Equivalents Restricted Cash And Restricted Cash Equivalents CashCashEquivalentsRestrictedCashAndRestrictedCashEquivalents	625000000	USD
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CY2018Q4	us-gaap	Cash Cash Equivalents Restricted Cash And Restricted Cash Equivalents CashCashEquivalentsRestrictedCashAndRestrictedCashEquivalents	83000000	USD
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CY2020	us-gaap	Financing Receivable Allowance For Credit Losses Policy For Uncollectible Amounts FinancingReceivableAllowanceForCreditLossesPolicyForUncollectibleAmounts	<div style="margin-bottom:3pt;text-align:justify"><span style="color:#000000;font-family:'Times New Roman',sans-serif;font-size:9pt;font-weight:700;line-height:120%">Measurement of Credit Losses on Financial Instruments (CECL)</span></div><div style="margin-bottom:9pt;text-align:justify"><span style="color:#000000;font-family:'Times New Roman',sans-serif;font-size:9pt;font-weight:400;line-height:120%">On January 1, 2020 Ambac adopted ASU 2016-13, </span><span style="color:#000000;font-family:'Times New Roman',sans-serif;font-size:9pt;font-style:italic;font-weight:400;line-height:120%">Financial Instruments-Credit Losses (Topic 326) - Measurement of Credit Losses on Financial Instruments, </span><span style="color:#000000;font-family:'Times New Roman',sans-serif;font-size:9pt;font-weight:400;line-height:120%">subsequently amended by ASU 2018-19</span><span style="color:#000000;font-family:'Times New Roman',sans-serif;font-size:9pt;font-style:italic;font-weight:400;line-height:120%">, Codification Improvements to Topic 326, Financial Instruments - Credit Losses; </span><span style="color:#000000;font-family:'Times New Roman',sans-serif;font-size:9pt;font-weight:400;line-height:120%">ASU 2019-04</span><span style="color:#000000;font-family:'Times New Roman',sans-serif;font-size:9pt;font-style:italic;font-weight:400;line-height:120%">, Codification Improvements to Topic 326, Financial Instruments—Credit Losses, Topic 815, Derivatives and Hedging, and Topic 825, Financial Instruments</span><span style="color:#000000;font-family:'Times New Roman',sans-serif;font-size:9pt;font-weight:400;line-height:120%">; ASU 2019-05, </span><span style="color:#000000;font-family:'Times New Roman',sans-serif;font-size:9pt;font-style:italic;font-weight:400;line-height:120%">Financial Instruments—Credit Losses (Topic 326): Targeted Transition Relief</span><span style="color:#000000;font-family:'Times New Roman',sans-serif;font-size:9pt;font-weight:400;line-height:120%">; and ASU 2019-11, </span><span style="color:#000000;font-family:'Times New Roman',sans-serif;font-size:9pt;font-style:italic;font-weight:400;line-height:120%">Codification Improvements to Topic 326, Financial Instruments - Credit Losses (collectively the Current Expected Credit Loss standard or "CECL").</span></div><div style="margin-bottom:9pt;text-align:justify"><span style="color:#000000;font-family:'Times New Roman',sans-serif;font-size:9pt;font-weight:400;line-height:120%">The new CECL standard affects how reporting entities measure credit losses for financial assets that are not accounted for at fair value through net income. For Ambac, these financial assets include available-for-sale debt securities and amortized cost assets, specifically premium receivables, reinsurance recoverables and loans. CECL does not apply to recoveries of previously paid losses on financial guarantee insurance contracts accounted for under ASC 944 nor does it apply to equity method investments accounted for under ASC 323. </span></div><div style="margin-bottom:3pt;padding-left:18pt;text-align:justify;text-indent:-9pt"><span style="color:#000000;font-family:'Times New Roman',sans-serif;font-size:9pt;font-weight:400;line-height:120%">•</span><span style="color:#000000;font-family:'Times New Roman',sans-serif;font-size:9pt;font-weight:400;line-height:120%;padding-left:5.85pt">For available-for-sale debt securities, credit losses under CECL are measured similarly to other-than-temporary impairments under prior GAAP. The updated guidance was applied prospectively. </span></div><div style="margin-bottom:9pt;padding-left:18pt;text-align:justify;text-indent:-9pt"><span style="color:#000000;font-family:'Times New Roman',sans-serif;font-size:9pt;font-weight:400;line-height:120%">•</span><span style="color:#000000;font-family:'Times New Roman',sans-serif;font-size:9pt;font-weight:400;line-height:120%;padding-left:5.85pt">For financial instruments measured at amortized cost, CECL replaces the "incurred loss" model, which generally delayed recognition of the full amount of credit losses until the loss was probable of occurring, with an "expected loss" model, which reflects an entity's current estimate of all expected lifetime credit losses. The estimate of expected lifetime credit losses should consider historical information, current information, as well as reasonable and supportable forecasts. Expected lifetime credit losses for amortized cost assets will be recorded as an allowance for credit losses, with subsequent increases or decreases in the allowance reflected in net income each period. The updated guidance was applied by a cumulative effect adjustment to the opening balance of retained earnings at January 1, 2020. This adjustment was not material to retained earnings or any individual balance sheet line item. Refer to the discussion below for each asset type. </span></div>As a result of adopting CECL, management revised its policies and procedures around the credit impairment evaluation process. CECL also introduced new disclosures related to the credit impairment process, including certain accounting policy elections that Ambac made under the new standard.
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AMBAC FINANCIAL GROUP, INC.

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Preferred Stock Value

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Common Stock Par Or Stated Value Per Share

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Common Stock Par Or Stated Value Per Share

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Common Stock Shares Authorized

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CY2020Q4

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Common Stock Shares Authorized

CommonStockSharesAuthorized

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CY2020Q4

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CommonStockSharesIssued

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CY2019Q4

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Common Stock Shares Issued

CommonStockSharesIssued

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Common Stock Value

CommonStockValue

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CY2019Q4

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Common Stock Value

CommonStockValue

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CY2020Q4

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CY2019Q4

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Additional Paid In Capital

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CY2020Q4

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Accumulated Other Comprehensive Income Loss Net Of Tax

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CY2019Q4

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CY2020Q4

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Retained Earnings Accumulated Deficit

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CY2019Q4

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Retained Earnings Accumulated Deficit

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CY2020Q4

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Treasury Stock Shares

TreasuryStockShares

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CY2019Q4

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Treasury Stock Shares

TreasuryStockShares

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CY2020Q4

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CY2019Q4

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Treasury Stock Value

TreasuryStockValue

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CY2020Q4

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Stockholders Equity

StockholdersEquity

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CY2019Q4

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Stockholders Equity

StockholdersEquity

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CY2019Q4

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Minority Interest

MinorityInterest

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CY2020Q4

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Minority Interest

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CY2019Q4

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Minority Interest

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Stockholders Equity Including Portion Attributable To Noncontrolling Interest

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CY2019Q4

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Stockholders Equity Including Portion Attributable To Noncontrolling Interest

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Liabilities And Stockholders Equity

LiabilitiesAndStockholdersEquity

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CY2019Q4

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Liabilities And Stockholders Equity

LiabilitiesAndStockholdersEquity

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CY2020

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Premiums Earned Net Financial Guarantee Insurance Contracts

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Premiums Earned Net Financial Guarantee Insurance Contracts

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Premiums Earned Net Financial Guarantee Insurance Contracts

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CY2020

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Net Investment Income

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Net Investment Income

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Net Investment Income

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CY2020

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Realized Investment Gains Losses

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CY2019

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Realized Investment Gains Losses

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Realized Investment Gains Losses

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Derivative Gain Loss On Derivative Net

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CY2019

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Derivative Gain Loss On Derivative Net

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Derivative Gain Loss On Derivative Net

DerivativeGainLossOnDerivativeNet

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CY2020

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Gains Losses On Extinguishment Of Debt

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CY2019

us-gaap

Gains Losses On Extinguishment Of Debt

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Gains Losses On Extinguishment Of Debt

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CY2019

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Other Income

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CY2018

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Other Income

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CY2020

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Variable Interest Entity Activity Between Vie And Entity Operating Income Or Loss

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CY2019

us-gaap

Variable Interest Entity Activity Between Vie And Entity Operating Income Or Loss

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CY2018

us-gaap

Variable Interest Entity Activity Between Vie And Entity Operating Income Or Loss

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CY2020

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Revenues

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Incurred Claims Financial Guarantee Insurance Contracts

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Incurred Claims Financial Guarantee Insurance Contracts

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Incurred Claims Financial Guarantee Insurance Contracts

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Amortization Of Intangible Assets

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Amortization Of Intangible Assets

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CY2020

us-gaap

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Other Underwriting Expense

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CY2018

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Other Underwriting Expense

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CY2020

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Interest Expense Debt

InterestExpenseDebt

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CY2019

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Interest Expense Debt

InterestExpenseDebt

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Interest Expense Debt

InterestExpenseDebt

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CY2020

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Benefits Losses And Expenses

BenefitsLossesAndExpenses

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CY2019

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Benefits Losses And Expenses

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CY2018

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Benefits Losses And Expenses

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Income Loss From Continuing Operations Before Income Taxes Minority Interest And Income Loss From Equity Method Investments

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Income Loss From Continuing Operations Before Income Taxes Minority Interest And Income Loss From Equity Method Investments

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us-gaap

Income Loss From Continuing Operations Before Income Taxes Minority Interest And Income Loss From Equity Method Investments

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Income Tax Expense Benefit

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Income Tax Expense Benefit

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Income Tax Expense Benefit

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CY2020

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Profit Loss

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CY2019

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Profit Loss

ProfitLoss

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CY2018

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Profit Loss

ProfitLoss

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Amps Exchange Loss Basedon Carry Value

AMPSExchangeLossBasedonCarryValue

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CY2019

ambc

Amps Exchange Loss Basedon Carry Value

AMPSExchangeLossBasedonCarryValue

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CY2018

ambc

Amps Exchange Loss Basedon Carry Value

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CY2020

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Net Income Loss

NetIncomeLoss

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Net Income Loss

NetIncomeLoss

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CY2018

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Net Income Loss

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Profit Loss

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Profit Loss

ProfitLoss

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CY2018

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Profit Loss

ProfitLoss

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CY2020

us-gaap

Other Comprehensive Income Unrealized Holding Gain Loss On Securities Arising During Period Net Of Tax

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us-gaap

Other Comprehensive Income Unrealized Holding Gain Loss On Securities Arising During Period Net Of Tax

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CY2020

ambc

Amps Exchange Loss Basedon Carry Value

AMPSExchangeLossBasedonCarryValue

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CY2018

us-gaap

Other Comprehensive Income Unrealized Holding Gain Loss On Securities Arising During Period Net Of Tax

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CY2020

us-gaap

Other Comprehensive Income Loss Foreign Currency Transaction And Translation Adjustment Net Of Tax

OtherComprehensiveIncomeLossForeignCurrencyTransactionAndTranslationAdjustmentNetOfTax

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CY2019

us-gaap

Other Comprehensive Income Loss Foreign Currency Transaction And Translation Adjustment Net Of Tax

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CY2018

us-gaap

Other Comprehensive Income Loss Foreign Currency Transaction And Translation Adjustment Net Of Tax

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CY2020

us-gaap

Other Comprehensive Income Loss Financial Liability Fair Value Option Reclassification Adjustment From Aoci For Derecognition After Tax

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us-gaap

Other Comprehensive Income Loss Financial Liability Fair Value Option Reclassification Adjustment From Aoci For Derecognition After Tax

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0

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CY2018

us-gaap

Other Comprehensive Income Loss Financial Liability Fair Value Option Reclassification Adjustment From Aoci For Derecognition After Tax

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CY2020

us-gaap

Other Comprehensive Income Loss Pension And Other Postretirement Benefit Plans Adjustment Net Of Tax

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us-gaap

Other Comprehensive Income Loss Pension And Other Postretirement Benefit Plans Adjustment Net Of Tax

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CY2018

us-gaap

Other Comprehensive Income Loss Pension And Other Postretirement Benefit Plans Adjustment Net Of Tax

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CY2020

us-gaap

Other Comprehensive Income Loss Net Of Tax

OtherComprehensiveIncomeLossNetOfTax

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CY2019

us-gaap

Other Comprehensive Income Loss Net Of Tax

OtherComprehensiveIncomeLossNetOfTax

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CY2018

us-gaap

Other Comprehensive Income Loss Net Of Tax

OtherComprehensiveIncomeLossNetOfTax

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CY2020

us-gaap

Comprehensive Income Net Of Tax Including Portion Attributable To Noncontrolling Interest

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CY2019

us-gaap

Comprehensive Income Net Of Tax Including Portion Attributable To Noncontrolling Interest

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CY2018

us-gaap

Comprehensive Income Net Of Tax Including Portion Attributable To Noncontrolling Interest

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CY2019

ambc

Amps Exchange Loss Basedon Carry Value

AMPSExchangeLossBasedonCarryValue

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CY2018

ambc

Amps Exchange Loss Basedon Carry Value

AMPSExchangeLossBasedonCarryValue

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CY2020

us-gaap

Comprehensive Income Net Of Tax

ComprehensiveIncomeNetOfTax

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CY2019

us-gaap

Comprehensive Income Net Of Tax

ComprehensiveIncomeNetOfTax

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CY2018

us-gaap

Comprehensive Income Net Of Tax

ComprehensiveIncomeNetOfTax

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CY2020

us-gaap

Earnings Per Share Basic

EarningsPerShareBasic

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CY2019

us-gaap

Earnings Per Share Basic

EarningsPerShareBasic

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CY2018

us-gaap

Earnings Per Share Basic

EarningsPerShareBasic

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CY2020

us-gaap

Earnings Per Share Diluted

EarningsPerShareDiluted

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CY2019

us-gaap

Earnings Per Share Diluted

EarningsPerShareDiluted

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CY2018

us-gaap

Earnings Per Share Diluted

EarningsPerShareDiluted

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CY2020

us-gaap

Weighted Average Number Of Shares Outstanding Basic

WeightedAverageNumberOfSharesOutstandingBasic

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CY2019

us-gaap

Weighted Average Number Of Shares Outstanding Basic

WeightedAverageNumberOfSharesOutstandingBasic

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CY2018

us-gaap

Weighted Average Number Of Shares Outstanding Basic

WeightedAverageNumberOfSharesOutstandingBasic

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CY2020

us-gaap

Weighted Average Number Of Diluted Shares Outstanding

WeightedAverageNumberOfDilutedSharesOutstanding

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shares

CY2019

us-gaap

Weighted Average Number Of Diluted Shares Outstanding

WeightedAverageNumberOfDilutedSharesOutstanding

45954908

shares

CY2018

us-gaap

Weighted Average Number Of Diluted Shares Outstanding

WeightedAverageNumberOfDilutedSharesOutstanding

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us-gaap

Stockholders Equity Including Portion Attributable To Noncontrolling Interest

StockholdersEquityIncludingPortionAttributableToNoncontrollingInterest

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us-gaap

Comprehensive Income Net Of Tax Including Portion Attributable To Noncontrolling Interest

ComprehensiveIncomeNetOfTaxIncludingPortionAttributableToNoncontrollingInterest

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CY2020

us-gaap

Allocated Share Based Compensation Expense

AllocatedShareBasedCompensationExpense

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CY2020

us-gaap

Stock Issued During Period Value Share Based Compensation

StockIssuedDuringPeriodValueShareBasedCompensation

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CY2020Q4

us-gaap

Stockholders Equity Including Portion Attributable To Noncontrolling Interest

StockholdersEquityIncludingPortionAttributableToNoncontrollingInterest

1140000000

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CY2019Q4

us-gaap

Redeemable Noncontrolling Interest Equity Other Fair Value

RedeemableNoncontrollingInterestEquityOtherFairValue

0

USD

CY2020

us-gaap

Noncontrolling Interest Increase From Subsidiary Equity Issuance

NoncontrollingInterestIncreaseFromSubsidiaryEquityIssuance

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CY2020Q4

us-gaap

Redeemable Noncontrolling Interest Equity Other Fair Value

RedeemableNoncontrollingInterestEquityOtherFairValue

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CY2018Q4

us-gaap

Stockholders Equity Including Portion Attributable To Noncontrolling Interest

StockholdersEquityIncludingPortionAttributableToNoncontrollingInterest

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us-gaap

Comprehensive Income Net Of Tax Including Portion Attributable To Noncontrolling Interest

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CY2019

us-gaap

Allocated Share Based Compensation Expense

AllocatedShareBasedCompensationExpense

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CY2019

us-gaap

Stock Issued During Period Value Share Based Compensation

StockIssuedDuringPeriodValueShareBasedCompensation

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CY2019

ambc

Amps Impacton Stockholders Equity

AMPSImpactonStockholdersEquity

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CY2019Q4

us-gaap

Stockholders Equity Including Portion Attributable To Noncontrolling Interest

StockholdersEquityIncludingPortionAttributableToNoncontrollingInterest

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CY2017Q4

us-gaap

Stockholders Equity Including Portion Attributable To Noncontrolling Interest

StockholdersEquityIncludingPortionAttributableToNoncontrollingInterest

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CY2018

us-gaap

Comprehensive Income Net Of Tax Including Portion Attributable To Noncontrolling Interest

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274000000

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CY2018

us-gaap

New Accounting Pronouncement Or Change In Accounting Principle Effect Of Adoption Quantification

NewAccountingPronouncementOrChangeInAccountingPrincipleEffectOfAdoptionQuantification

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CY2018

us-gaap

Allocated Share Based Compensation Expense

AllocatedShareBasedCompensationExpense

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CY2018

us-gaap

Stock Issued During Period Value Share Based Compensation

StockIssuedDuringPeriodValueShareBasedCompensation

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CY2018

ambc

Amps Impacton Stockholders Equity

AMPSImpactonStockholdersEquity

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CY2018Q4

us-gaap

Stockholders Equity Including Portion Attributable To Noncontrolling Interest

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CY2020

us-gaap

Net Income Loss

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CY2019

us-gaap

Net Income Loss

NetIncomeLoss

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CY2018

us-gaap

Net Income Loss

NetIncomeLoss

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CY2020

ambc

Amps Exchange Loss Basedon Carry Value

AMPSExchangeLossBasedonCarryValue

0

USD

CY2019

ambc

Amps Exchange Loss Basedon Carry Value

AMPSExchangeLossBasedonCarryValue

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USD

CY2018

ambc

Amps Exchange Loss Basedon Carry Value

AMPSExchangeLossBasedonCarryValue

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CY2020

us-gaap

Profit Loss

ProfitLoss

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CY2019

us-gaap

Profit Loss

ProfitLoss

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CY2018

us-gaap

Profit Loss

ProfitLoss

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CY2020

us-gaap

Depreciation Amortization And Accretion Net

DepreciationAmortizationAndAccretionNet

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CY2019

us-gaap

Depreciation Amortization And Accretion Net

DepreciationAmortizationAndAccretionNet

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CY2018

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Depreciation Amortization And Accretion Net

DepreciationAmortizationAndAccretionNet

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CY2020

us-gaap

Accretion Amortization Of Discounts And Premiums Investments

AccretionAmortizationOfDiscountsAndPremiumsInvestments

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CY2019

us-gaap

Accretion Amortization Of Discounts And Premiums Investments

AccretionAmortizationOfDiscountsAndPremiumsInvestments

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CY2018

us-gaap

Accretion Amortization Of Discounts And Premiums Investments

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CY2020

us-gaap

Share Based Compensation

ShareBasedCompensation

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CY2019

us-gaap

Share Based Compensation

ShareBasedCompensation

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CY2018

us-gaap

Share Based Compensation

ShareBasedCompensation

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CY2020

us-gaap

Increase Decrease In Deferred Income Taxes

IncreaseDecreaseInDeferredIncomeTaxes

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CY2019

us-gaap

Increase Decrease In Deferred Income Taxes

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CY2018

us-gaap

Increase Decrease In Deferred Income Taxes

IncreaseDecreaseInDeferredIncomeTaxes

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CY2020

us-gaap

Increase Decrease In Accrued Income Taxes Payable

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CY2019

us-gaap

Increase Decrease In Accrued Income Taxes Payable

IncreaseDecreaseInAccruedIncomeTaxesPayable

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CY2018

us-gaap

Increase Decrease In Accrued Income Taxes Payable

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CY2020

us-gaap

Increase Decrease In Unearned Premiums

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CY2019

us-gaap

Increase Decrease In Unearned Premiums

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CY2018

us-gaap

Increase Decrease In Unearned Premiums

IncreaseDecreaseInUnearnedPremiums

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us-gaap

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CY2019

us-gaap

Increase Decrease In Liability For Claims And Claims Adjustment Expense Reserve

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us-gaap

Increase Decrease In Liability For Claims And Claims Adjustment Expense Reserve

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CY2020

us-gaap

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CY2019

us-gaap

Increase Decrease In Reinsurance Payables

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us-gaap

Increase Decrease In Reinsurance Payables

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CY2020

us-gaap

Increase Decrease In Premiums Receivable

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CY2019

us-gaap

Increase Decrease In Premiums Receivable

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CY2018

us-gaap

Increase Decrease In Premiums Receivable

IncreaseDecreaseInPremiumsReceivable

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CY2020

us-gaap

Increase Decrease In Interest Payable Net

IncreaseDecreaseInInterestPayableNet

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CY2019

us-gaap

Increase Decrease In Interest Payable Net

IncreaseDecreaseInInterestPayableNet

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CY2018

us-gaap

Increase Decrease In Interest Payable Net

IncreaseDecreaseInInterestPayableNet

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CY2020

us-gaap

Amortization Of Intangible Assets

AmortizationOfIntangibleAssets

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CY2019

us-gaap

Amortization Of Intangible Assets

AmortizationOfIntangibleAssets

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CY2018

us-gaap

Amortization Of Intangible Assets

AmortizationOfIntangibleAssets

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CY2020

us-gaap

Realized Investment Gains Losses

RealizedInvestmentGainsLosses

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CY2019

us-gaap

Realized Investment Gains Losses

RealizedInvestmentGainsLosses

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CY2018

us-gaap

Realized Investment Gains Losses

RealizedInvestmentGainsLosses

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CY2020

us-gaap

Gains Losses On Extinguishment Of Debt

GainsLossesOnExtinguishmentOfDebt

0

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CY2019

us-gaap

Gains Losses On Extinguishment Of Debt

GainsLossesOnExtinguishmentOfDebt

0

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CY2018

us-gaap

Gains Losses On Extinguishment Of Debt

GainsLossesOnExtinguishmentOfDebt

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CY2020

us-gaap

Variable Interest Entity Activity Between Vie And Entity Operating Income Or Loss

VariableInterestEntityActivityBetweenVIEAndEntityOperatingIncomeOrLoss

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CY2019

us-gaap

Variable Interest Entity Activity Between Vie And Entity Operating Income Or Loss

VariableInterestEntityActivityBetweenVIEAndEntityOperatingIncomeOrLoss

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CY2018

us-gaap

Variable Interest Entity Activity Between Vie And Entity Operating Income Or Loss

VariableInterestEntityActivityBetweenVIEAndEntityOperatingIncomeOrLoss

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CY2020

us-gaap

Increase Decrease In Derivative Assets And Liabilities

IncreaseDecreaseInDerivativeAssetsAndLiabilities

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CY2019

us-gaap

Increase Decrease In Derivative Assets And Liabilities

IncreaseDecreaseInDerivativeAssetsAndLiabilities

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CY2018

us-gaap

Increase Decrease In Derivative Assets And Liabilities

IncreaseDecreaseInDerivativeAssetsAndLiabilities

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CY2020

us-gaap

Increase Decrease In Other Operating Capital Net

IncreaseDecreaseInOtherOperatingCapitalNet

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CY2019

us-gaap

Increase Decrease In Other Operating Capital Net

IncreaseDecreaseInOtherOperatingCapitalNet

-79000000

USD

CY2018

us-gaap

Increase Decrease In Other Operating Capital Net

IncreaseDecreaseInOtherOperatingCapitalNet

-68000000

USD

CY2020

us-gaap

Net Cash Provided By Used In Operating Activities

NetCashProvidedByUsedInOperatingActivities

-175000000

USD

CY2019

us-gaap

Net Cash Provided By Used In Operating Activities

NetCashProvidedByUsedInOperatingActivities

-311000000

USD

CY2018

us-gaap

Net Cash Provided By Used In Operating Activities

NetCashProvidedByUsedInOperatingActivities

-1543000000

USD

CY2020

us-gaap

Proceeds From Sale Of Available For Sale Securities

ProceedsFromSaleOfAvailableForSaleSecurities

1109000000

USD

CY2019

us-gaap

Proceeds From Sale Of Available For Sale Securities

ProceedsFromSaleOfAvailableForSaleSecurities

1212000000

USD

CY2018

us-gaap

Proceeds From Sale Of Available For Sale Securities

ProceedsFromSaleOfAvailableForSaleSecurities

1248000000

USD

CY2020

us-gaap

Proceeds From Maturities Prepayments And Calls Of Available For Sale Securities

ProceedsFromMaturitiesPrepaymentsAndCallsOfAvailableForSaleSecurities

137000000

USD

CY2019

us-gaap

Proceeds From Maturities Prepayments And Calls Of Available For Sale Securities

ProceedsFromMaturitiesPrepaymentsAndCallsOfAvailableForSaleSecurities

379000000

USD

CY2018

us-gaap

Proceeds From Maturities Prepayments And Calls Of Available For Sale Securities

ProceedsFromMaturitiesPrepaymentsAndCallsOfAvailableForSaleSecurities

432000000

USD

CY2020

us-gaap

Payments To Acquire Available For Sale Securities

PaymentsToAcquireAvailableForSaleSecurities

975000000

USD

CY2019

us-gaap

Payments To Acquire Available For Sale Securities

PaymentsToAcquireAvailableForSaleSecurities

959000000

USD

CY2018

us-gaap

Payments To Acquire Available For Sale Securities

PaymentsToAcquireAvailableForSaleSecurities

528000000

USD

CY2020

us-gaap

Proceeds From Sale And Maturity Of Other Investments

ProceedsFromSaleAndMaturityOfOtherInvestments

374000000

USD

CY2019

us-gaap

Proceeds From Sale And Maturity Of Other Investments

ProceedsFromSaleAndMaturityOfOtherInvestments

81000000

USD

CY2018

us-gaap

Proceeds From Sale And Maturity Of Other Investments

ProceedsFromSaleAndMaturityOfOtherInvestments

159000000

USD

CY2020

us-gaap

Payments To Acquire Other Investments

PaymentsToAcquireOtherInvestments

475000000

USD

CY2019

us-gaap

Payments To Acquire Other Investments

PaymentsToAcquireOtherInvestments

137000000

USD

CY2018

us-gaap

Payments To Acquire Other Investments

PaymentsToAcquireOtherInvestments

140000000

USD

CY2020

us-gaap

Payments For Proceeds From Short Term Investments

PaymentsForProceedsFromShortTermInvestments

-158000000

USD

CY2019

us-gaap

Payments For Proceeds From Short Term Investments

PaymentsForProceedsFromShortTermInvestments

218000000

USD

CY2018

us-gaap

Payments For Proceeds From Short Term Investments

PaymentsForProceedsFromShortTermInvestments

-127000000

USD

CY2020

us-gaap

Increase Decrease Cash Collateral From Counterparties

IncreaseDecreaseCashCollateralFromCounterparties

0

USD

CY2019

us-gaap

Increase Decrease Cash Collateral From Counterparties

IncreaseDecreaseCashCollateralFromCounterparties

100000000

USD

CY2018

us-gaap

Increase Decrease Cash Collateral From Counterparties

IncreaseDecreaseCashCollateralFromCounterparties

-58000000

USD

CY2020

ambc

Proceeds From Financial Guaranty Variable Interest Entity Assets

ProceedsFromFinancialGuarantyVariableInterestEntityAssets

178000000

USD

CY2019

ambc

Proceeds From Financial Guaranty Variable Interest Entity Assets

ProceedsFromFinancialGuarantyVariableInterestEntityAssets

543000000

USD

CY2018

ambc

Proceeds From Financial Guaranty Variable Interest Entity Assets

ProceedsFromFinancialGuarantyVariableInterestEntityAssets

349000000

USD

CY2020

us-gaap

Payments To Acquire Businesses Net Of Cash Acquired

PaymentsToAcquireBusinessesNetOfCashAcquired

-74000000

USD

CY2020

us-gaap

Payments For Proceeds From Other Investing Activities

PaymentsForProceedsFromOtherInvestingActivities

-1000000

USD

CY2019

us-gaap

Payments For Proceeds From Other Investing Activities

PaymentsForProceedsFromOtherInvestingActivities

2000000

USD

CY2018

us-gaap

Payments For Proceeds From Other Investing Activities

PaymentsForProceedsFromOtherInvestingActivities

0

USD

CY2020

us-gaap

Net Cash Provided By Used In Investing Activities

NetCashProvidedByUsedInInvestingActivities

432000000

USD

CY2019

us-gaap

Net Cash Provided By Used In Investing Activities

NetCashProvidedByUsedInInvestingActivities

1000000000

USD

CY2018

us-gaap

Net Cash Provided By Used In Investing Activities

NetCashProvidedByUsedInInvestingActivities

1588000000

USD

CY2020

ambc

Proceeds From Issuanceof Tier Ii Notes

ProceedsFromIssuanceofTierIINotes

0

USD

CY2019

ambc

Proceeds From Issuanceof Tier Ii Notes

ProceedsFromIssuanceofTierIINotes

0

USD

CY2018

ambc

Proceeds From Issuanceof Tier Ii Notes

ProceedsFromIssuanceofTierIINotes

240000000

USD

CY2020

ambc

Proceeds From Issuanceof Ambac Uk Debt

ProceedsFromIssuanceofAmbacUKDebt

0

USD

CY2019

ambc

Proceeds From Issuanceof Ambac Uk Debt

ProceedsFromIssuanceofAmbacUKDebt

12000000

USD

CY2018

ambc

Proceeds From Issuanceof Ambac Uk Debt

ProceedsFromIssuanceofAmbacUKDebt

0

USD

CY2020

ambc

Proceedsfrom Saleof Senior Surplus Notes

ProceedsfromSaleofSeniorSurplusNotes

0

USD

CY2019

ambc

Proceedsfrom Saleof Senior Surplus Notes

ProceedsfromSaleofSeniorSurplusNotes

0

USD

CY2018

ambc

Proceedsfrom Saleof Senior Surplus Notes

ProceedsfromSaleofSeniorSurplusNotes

24000000

USD

CY2020

ambc

Paydownof Ambac Note

PaydownofAmbacNote

121000000

USD

CY2019

ambc

Paydownof Ambac Note

PaydownofAmbacNote

178000000

USD

CY2018

ambc

Paydownof Ambac Note

PaydownofAmbacNote

214000000

USD

CY2020

ambc

Paydown Of Variable Interest Entity Secured Borrowing

PaydownOfVariableInterestEntitySecuredBorrowing

0

USD

CY2019

ambc

Paydown Of Variable Interest Entity Secured Borrowing

PaydownOfVariableInterestEntitySecuredBorrowing

0

USD

CY2018

ambc

Paydown Of Variable Interest Entity Secured Borrowing

PaydownOfVariableInterestEntitySecuredBorrowing

74000000

USD

CY2020

us-gaap

Repayments Of Long Term Debt

RepaymentsOfLongTermDebt

0

USD

CY2019

us-gaap

Repayments Of Long Term Debt

RepaymentsOfLongTermDebt

0

USD

CY2018

us-gaap

Repayments Of Long Term Debt

RepaymentsOfLongTermDebt

191000000

USD

CY2020

us-gaap

Payments Of Debt Issuance Costs

PaymentsOfDebtIssuanceCosts

0

USD

CY2019

us-gaap

Payments Of Debt Issuance Costs

PaymentsOfDebtIssuanceCosts

0

USD

CY2018

us-gaap

Payments Of Debt Issuance Costs

PaymentsOfDebtIssuanceCosts

9000000

USD

CY2020

ambc

Amps Proceeds

AMPSProceeds

0

USD

CY2019

ambc

Amps Proceeds

AMPSProceeds

19000000

USD

CY2018

ambc

Amps Proceeds

AMPSProceeds

0

USD

CY2020

ambc

Amps Exchange Cash Paid

AMPSExchangeCashPaid

0

USD

CY2019

ambc

Amps Exchange Cash Paid

AMPSExchangeCashPaid

0

USD

CY2018

ambc

Amps Exchange Cash Paid

AMPSExchangeCashPaid

11000000

USD

CY2020

us-gaap

Payments Related To Tax Withholding For Share Based Compensation

PaymentsRelatedToTaxWithholdingForShareBasedCompensation

3000000

USD

CY2019

us-gaap

Payments Related To Tax Withholding For Share Based Compensation

PaymentsRelatedToTaxWithholdingForShareBasedCompensation

3000000

USD

CY2018

us-gaap

Payments Related To Tax Withholding For Share Based Compensation

PaymentsRelatedToTaxWithholdingForShareBasedCompensation

1000000

USD

CY2020

ambc

Paydownof Financial Guaranty Variable Interest Entity Liabilities

PaydownofFinancialGuarantyVariableInterestEntityLiabilities

178000000

USD

CY2019

ambc

Paydownof Financial Guaranty Variable Interest Entity Liabilities

PaydownofFinancialGuarantyVariableInterestEntityLiabilities

542000000

USD

CY2018

ambc

Paydownof Financial Guaranty Variable Interest Entity Liabilities

PaydownofFinancialGuarantyVariableInterestEntityLiabilities

349000000

USD

CY2020

us-gaap

Net Cash Provided By Used In Financing Activities

NetCashProvidedByUsedInFinancingActivities

-303000000

USD

CY2019

us-gaap

Net Cash Provided By Used In Financing Activities

NetCashProvidedByUsedInFinancingActivities

-691000000

USD

CY2018

us-gaap

Net Cash Provided By Used In Financing Activities

NetCashProvidedByUsedInFinancingActivities

-585000000

USD

CY2020

us-gaap

Effect Of Exchange Rate On Cash And Cash Equivalents

EffectOfExchangeRateOnCashAndCashEquivalents

0

USD

CY2019

us-gaap

Effect Of Exchange Rate On Cash And Cash Equivalents

EffectOfExchangeRateOnCashAndCashEquivalents

0

USD

CY2018

us-gaap

Effect Of Exchange Rate On Cash And Cash Equivalents

EffectOfExchangeRateOnCashAndCashEquivalents

0

USD

CY2020

us-gaap

Cash And Cash Equivalents Period Increase Decrease

CashAndCashEquivalentsPeriodIncreaseDecrease

-46000000

USD

CY2019

us-gaap

Cash And Cash Equivalents Period Increase Decrease

CashAndCashEquivalentsPeriodIncreaseDecrease

-2000000

USD

CY2018

us-gaap

Cash And Cash Equivalents Period Increase Decrease

CashAndCashEquivalentsPeriodIncreaseDecrease

-541000000

USD

CY2019Q4

us-gaap

Cash Cash Equivalents Restricted Cash And Restricted Cash Equivalents

CashCashEquivalentsRestrictedCashAndRestrictedCashEquivalents

81000000

USD

CY2018Q4

us-gaap

Cash Cash Equivalents Restricted Cash And Restricted Cash Equivalents

CashCashEquivalentsRestrictedCashAndRestrictedCashEquivalents

83000000

USD

CY2017Q4

us-gaap

Cash Cash Equivalents Restricted Cash And Restricted Cash Equivalents

CashCashEquivalentsRestrictedCashAndRestrictedCashEquivalents

625000000

USD

CY2020Q4

us-gaap

Cash Cash Equivalents Restricted Cash And Restricted Cash Equivalents

CashCashEquivalentsRestrictedCashAndRestrictedCashEquivalents

35000000

USD

CY2019Q4

us-gaap

Cash Cash Equivalents Restricted Cash And Restricted Cash Equivalents

CashCashEquivalentsRestrictedCashAndRestrictedCashEquivalents

81000000

USD

CY2018Q4

us-gaap

Cash Cash Equivalents Restricted Cash And Restricted Cash Equivalents

CashCashEquivalentsRestrictedCashAndRestrictedCashEquivalents

83000000

USD

CY1991Q2

dei

Entity Incorporation Date Of Incorporation

EntityIncorporationDateOfIncorporation

1991-04-29

CY2020Q4

us-gaap

Business Acquisition Percentage Of Voting Interests Acquired

BusinessAcquisitionPercentageOfVotingInterestsAcquired

0.80

CY1991Q2

ambc

Common Stock Voting Restrictions

CommonStockVotingRestrictions

0.10

CY1991Q2

ambc

Common Stock Voting Restriction Less One Vote

CommonStockVotingRestrictionLessOneVote

0.10

CY1991Q2

ambc

Common Stock Transfer Restrictions

CommonStockTransferRestrictions

0.05

CY2014

ambc

Common Stock Additional Transfer Restrictions

CommonStockAdditionalTransferRestrictions

0.05

CY2018Q1

ambc

Satisfactionanddischargeofsegregatedaccountdeferredamountsanddeferredinterest

3857000000

USD

CY2018Q1

ambc

Cancellationof Surplus Notes Principal

CancellationofSurplusNotesPrincipal

552000000

USD

CY2018Q1

ambc

Cancellationof Surplus Notes Accrued Interest

CancellationofSurplusNotesAccruedInterest

257000000

USD

CY2020Q4

ambc

Market Valueof Secured Note Collateral

MarketValueofSecuredNoteCollateral

178000000

USD

CY2018Q1

ambc

Tier2 Notes

Tier2Notes

240000000

USD

CY2018Q1

ambc

Tier2 Note Securityin Rmbs Litigation Settlement Proceeds

Tier2NoteSecurityinRMBSLitigationSettlementProceeds

1600000000

USD

CY2018Q2

us-gaap

Minority Interest

MinorityInterest

264000000

USD

CY2018Q3

ambc

Amps Liquidation Preference Value Per Share

AMPSLiquidationPreferenceValuePerShare

25000

CY2018Q3

ambc

Amps Exchange Surplus Notes Issued Per Share

AMPSExchangeSurplusNotesIssuedPerShare

13875

CY2018Q3

ambc

Amps Exchange Shares Tendered

AMPSExchangeSharesTendered

22096

shares

CY2018Q3

ambc

Amps Exchange Cash Paid Per Share

AMPSExchangeCashPaidPerShare

500

CY2018Q3

ambc

Amps Exchange Warrants Issued Per Share

AMPSExchangeWarrantsIssuedPerShare

37.3076

CY2013Q2

us-gaap

Class Of Warrant Or Right Exercise Price Of Warrants Or Rights1

ClassOfWarrantOrRightExercisePriceOfWarrantsOrRights1

16.67

CY2018Q3

ambc

Amps Exchange Percent Acquired

AMPSExchangePercentAcquired

0.844

CY2018Q3

ambc

Amps Exchange Shares Acquired

AMPSExchangeSharesAcquired

22296

shares

CY2018Q3

ambc

Amps Exchange Aggregated Liquidation Preference

AMPSExchangeAggregatedLiquidationPreference

557000000

USD

CY2018Q3

ambc

Amps Exchange Nominal Discount

AMPSExchangeNominalDiscount

227000000

USD

CY2018Q3

ambc

Amps Exchange Nominal Discountat Fair Value

AMPSExchangeNominalDiscountatFairValue

253000000

USD

CY2018Q3

ambc

Amps Exchange Aggregated Liquidation Preference

AMPSExchangeAggregatedLiquidationPreference

557000000

USD

CY2018Q3

ambc

Amps Exchange Total Surplus Notes Issued

AMPSExchangeTotalSurplusNotesIssued

213000000

USD

CY2018Q3

ambc

Amps Exchange Interest Includedin Surplus Notes Issued

AMPSExchangeInterestIncludedinSurplusNotesIssued

98000000

USD

CY2018Q3

ambc

Amps Exchange Total Warrants Issued

AMPSExchangeTotalWarrantsIssued

824307

ambc

Amps Exchange Cash Paid

AMPSExchangeCashPaid

11000000

USD

CY2018

ambc

Amps Exchange Loss Basedon Carry Value

AMPSExchangeLossBasedonCarryValue

82000000

USD

CY2019Q4

us-gaap

Minority Interest

MinorityInterest

60000000

USD

CY2020

us-gaap

Financing Receivable Allowance For Credit Losses Policy For Uncollectible Amounts

FinancingReceivableAllowanceForCreditLossesPolicyForUncollectibleAmounts

<div style="margin-bottom:3pt;text-align:justify"><span style="color:#000000;font-family:'Times New Roman',sans-serif;font-size:9pt;font-weight:700;line-height:120%">Measurement of Credit Losses on Financial Instruments (CECL)</span></div><div style="margin-bottom:9pt;text-align:justify"><span style="color:#000000;font-family:'Times New Roman',sans-serif;font-size:9pt;font-weight:400;line-height:120%">On January 1, 2020 Ambac adopted ASU 2016-13, </span><span style="color:#000000;font-family:'Times New Roman',sans-serif;font-size:9pt;font-style:italic;font-weight:400;line-height:120%">Financial Instruments-Credit Losses (Topic 326) - Measurement of Credit Losses on Financial Instruments, </span><span style="color:#000000;font-family:'Times New Roman',sans-serif;font-size:9pt;font-weight:400;line-height:120%">subsequently amended by ASU 2018-19</span><span style="color:#000000;font-family:'Times New Roman',sans-serif;font-size:9pt;font-style:italic;font-weight:400;line-height:120%">, Codification Improvements to Topic 326, Financial Instruments - Credit Losses; </span><span style="color:#000000;font-family:'Times New Roman',sans-serif;font-size:9pt;font-weight:400;line-height:120%">ASU 2019-04</span><span style="color:#000000;font-family:'Times New Roman',sans-serif;font-size:9pt;font-style:italic;font-weight:400;line-height:120%">, Codification Improvements to Topic 326, Financial Instruments—Credit Losses, Topic 815, Derivatives and Hedging, and Topic 825, Financial Instruments</span><span style="color:#000000;font-family:'Times New Roman',sans-serif;font-size:9pt;font-weight:400;line-height:120%">; ASU 2019-05, </span><span style="color:#000000;font-family:'Times New Roman',sans-serif;font-size:9pt;font-style:italic;font-weight:400;line-height:120%">Financial Instruments—Credit Losses (Topic 326): Targeted Transition Relief</span><span style="color:#000000;font-family:'Times New Roman',sans-serif;font-size:9pt;font-weight:400;line-height:120%">; and ASU 2019-11, </span><span style="color:#000000;font-family:'Times New Roman',sans-serif;font-size:9pt;font-style:italic;font-weight:400;line-height:120%">Codification Improvements to Topic 326, Financial Instruments - Credit Losses (collectively the Current Expected Credit Loss standard or "CECL").</span></div><div style="margin-bottom:9pt;text-align:justify"><span style="color:#000000;font-family:'Times New Roman',sans-serif;font-size:9pt;font-weight:400;line-height:120%">The new CECL standard affects how reporting entities measure credit losses for financial assets that are not accounted for at fair value through net income. For Ambac, these financial assets include available-for-sale debt securities and amortized cost assets, specifically premium receivables, reinsurance recoverables and loans. CECL does not apply to recoveries of previously paid losses on financial guarantee insurance contracts accounted for under ASC 944 nor does it apply to equity method investments accounted for under ASC 323. </span></div><div style="margin-bottom:3pt;padding-left:18pt;text-align:justify;text-indent:-9pt"><span style="color:#000000;font-family:'Times New Roman',sans-serif;font-size:9pt;font-weight:400;line-height:120%">•</span><span style="color:#000000;font-family:'Times New Roman',sans-serif;font-size:9pt;font-weight:400;line-height:120%;padding-left:5.85pt">For available-for-sale debt securities, credit losses under CECL are measured similarly to other-than-temporary impairments under prior GAAP. The updated guidance was applied prospectively. </span></div><div style="margin-bottom:9pt;padding-left:18pt;text-align:justify;text-indent:-9pt"><span style="color:#000000;font-family:'Times New Roman',sans-serif;font-size:9pt;font-weight:400;line-height:120%">•</span><span style="color:#000000;font-family:'Times New Roman',sans-serif;font-size:9pt;font-weight:400;line-height:120%;padding-left:5.85pt">For financial instruments measured at amortized cost, CECL replaces the "incurred loss" model, which generally delayed recognition of the full amount of credit losses until the loss was probable of occurring, with an "expected loss" model, which reflects an entity's current estimate of all expected lifetime credit losses. The estimate of expected lifetime credit losses should consider historical information, current information, as well as reasonable and supportable forecasts. Expected lifetime credit losses for amortized cost assets will be recorded as an allowance for credit losses, with subsequent increases or decreases in the allowance reflected in net income each period. The updated guidance was applied by a cumulative effect adjustment to the opening balance of retained earnings at January 1, 2020. This adjustment was not material to retained earnings or any individual balance sheet line item. Refer to the discussion below for each asset type. </span></div>As a result of adopting CECL, management revised its policies and procedures around the credit impairment evaluation process. CECL also introduced new disclosures related to the credit impairment process, including certain accounting policy elections that Ambac made under the new standard.

CY2020Q4

ambc

Estimated Future Premium Payments Weighted Average Discounted Rate

EstimatedFuturePremiumPaymentsWeightedAverageDiscountedRate

0.022

CY2019Q4

ambc

Estimated Future Premium Payments Weighted Average Discounted Rate

EstimatedFuturePremiumPaymentsWeightedAverageDiscountedRate

0.024

CY2020

us-gaap

Financial Guarantee Insurance Contracts Premium Received Over Contract Period Premium Receivable Weighted Average Collection Period1

FinancialGuaranteeInsuranceContractsPremiumReceivedOverContractPeriodPremiumReceivableWeightedAverageCollectionPeriod1

P8Y3M18D

CY2019

us-gaap

Financial Guarantee Insurance Contracts Premium Received Over Contract Period Premium Receivable Weighted Average Collection Period1

FinancialGuaranteeInsuranceContractsPremiumReceivedOverContractPeriodPremiumReceivableWeightedAverageCollectionPeriod1

P8Y6M

CY2020Q4

us-gaap

Goodwill Impaired Accumulated Impairment Loss

GoodwillImpairedAccumulatedImpairmentLoss

0

USD

CY2019Q3

ambc

Uk Income Tax Rate

UKIncomeTaxRate

0.19

CY2019Q4

us-gaap

Minority Interest

MinorityInterest

60000000

USD

CY2020Q4

us-gaap

Minority Interest

MinorityInterest

60000000

USD

CY2020Q4

us-gaap

Business Acquisition Percentage Of Voting Interests Acquired

BusinessAcquisitionPercentageOfVotingInterestsAcquired

0.80

CY2020Q4

ambc

Business Combination Redeemable Noncontrolling Percentage

BusinessCombinationRedeemableNoncontrollingPercentage

0.20

CY2020Q4

ambc

Business Combination Redeemable Noncontrolling Percentage

BusinessCombinationRedeemableNoncontrollingPercentage

0.20

CY2020

us-gaap

Foreign Currency Transaction Gain Loss Before Tax

ForeignCurrencyTransactionGainLossBeforeTax

-1000000

USD

CY2019

us-gaap

Foreign Currency Transaction Gain Loss Before Tax

ForeignCurrencyTransactionGainLossBeforeTax

12000000

USD

CY2018

us-gaap

Foreign Currency Transaction Gain Loss Before Tax

ForeignCurrencyTransactionGainLossBeforeTax

-7000000

USD

CY2019Q2

ambc

Uk Income Tax Rate

UKIncomeTaxRate

0.17

CY2020

us-gaap

Prior Period Reclassification Adjustment Description

PriorPeriodReclassificationAdjustmentDescription

<div style="margin-bottom:3pt;text-align:justify"><span style="color:#000000;font-family:'Times New Roman',sans-serif;font-size:9pt;font-weight:700;line-height:120%">Reclassifications and Rounding</span></div><div style="margin-bottom:9pt;text-align:justify"><span style="color:#000000;font-family:'Times New Roman',sans-serif;font-size:9pt;font-weight:400;line-height:120%">Reclassifications may have been made to prior years' amounts to conform to the current year's presentation. Certain amounts and tables in the consolidated financial statements and associated notes may not add due to rounding.</span></div>

CY2020

us-gaap

Income Taxes Paid

IncomeTaxesPaid

11000000

USD

CY2019

us-gaap

Income Taxes Paid

IncomeTaxesPaid

21000000

USD

CY2018

us-gaap

Income Taxes Paid

IncomeTaxesPaid

35000000

USD

CY2018Q3

ambc

Amps Exchange Carrying Valueof Surplus Notes Issued

AMPSExchangeCarryingValueofSurplusNotesIssued

187000000

USD

CY2019

ambc

Non Cash Exchange Of Puerto Rico Bonds

NonCashExchangeOfPuertoRicoBonds

510000000

USD

CY2018Q4

ambc

Non Cash Impactof Rehabilitation Exit Transaction

NonCashImpactofRehabilitationExitTransaction

1919000000

USD

CY2020Q4

us-gaap

Cash And Cash Equivalents At Carrying Value

CashAndCashEquivalentsAtCarryingValue

20000000

USD

CY2019Q4

us-gaap

Cash And Cash Equivalents At Carrying Value

CashAndCashEquivalentsAtCarryingValue

24000000

USD

CY2018Q4

us-gaap

Cash And Cash Equivalents At Carrying Value

CashAndCashEquivalentsAtCarryingValue

63000000

USD

CY2020Q4

us-gaap

Restricted Cash

RestrictedCash

13000000

USD

CY2019Q4

us-gaap

Restricted Cash

RestrictedCash

55000000

USD

CY2018Q4

us-gaap

Restricted Cash

RestrictedCash

19000000

USD

CY2020Q4

us-gaap

Cash Cash Equivalents Restricted Cash And Restricted Cash Equivalents

CashCashEquivalentsRestrictedCashAndRestrictedCashEquivalents

35000000

USD

CY2019Q4

us-gaap

Cash Cash Equivalents Restricted Cash And Restricted Cash Equivalents

CashCashEquivalentsRestrictedCashAndRestrictedCashEquivalents

81000000

USD

CY2018Q4

us-gaap

Cash Cash Equivalents Restricted Cash And Restricted Cash Equivalents

CashCashEquivalentsRestrictedCashAndRestrictedCashEquivalents

83000000

USD

CY2020Q4

us-gaap

Business Acquisition Percentage Of Voting Interests Acquired

BusinessAcquisitionPercentageOfVotingInterestsAcquired

0.80

CY2020

us-gaap

Business Combination Consideration Transferred1

BusinessCombinationConsiderationTransferred1

81000000

USD

CY2020Q4

ambc

Business Combination Redeemable Noncontrolling Percentage

BusinessCombinationRedeemableNoncontrollingPercentage

0.20

CY2020Q4

ambc

Business Combination Redeemable Noncontrolling Percentage

BusinessCombinationRedeemableNoncontrollingPercentage

0.20

CY2020

ambc

Variable Interest Entity Changein Fair Valueof Assetsand Liabilities

VariableInterestEntityChangeinFairValueofAssetsandLiabilities

-1000000

USD

CY2019

ambc

Variable Interest Entity Changein Fair Valueof Assetsand Liabilities

VariableInterestEntityChangeinFairValueofAssetsandLiabilities

13000000

USD

CY2018

ambc

Variable Interest Entity Changein Fair Valueof Assetsand Liabilities

VariableInterestEntityChangeinFairValueofAssetsandLiabilities

3000000

USD

CY2018

us-gaap

Other Comprehensive Income Loss Financial Liability Fair Value Option Reclassification Adjustment From Aoci For Derecognition Before Tax

OtherComprehensiveIncomeLossFinancialLiabilityFairValueOptionReclassificationAdjustmentFromAociForDerecognitionBeforeTax

-1000000

USD

CY2020

us-gaap

Variable Interest Entity Initial Consolidation Gain Or Loss

VariableInterestEntityInitialConsolidationGainOrLoss

0

USD

CY2019

us-gaap

Variable Interest Entity Initial Consolidation Gain Or Loss

VariableInterestEntityInitialConsolidationGainOrLoss

15000000

USD

CY2018

us-gaap

Variable Interest Entity Initial Consolidation Gain Or Loss

VariableInterestEntityInitialConsolidationGainOrLoss

0

USD

CY2020

ambc

Variable Interest Entities Deconsolidation Gain Loss

VariableInterestEntitiesDeconsolidationGainLoss

0

USD

CY2019

ambc

Variable Interest Entities Deconsolidation Gain Loss

VariableInterestEntitiesDeconsolidationGainLoss

-2000000

USD

CY2018

ambc

Variable Interest Entities Deconsolidation Gain Loss

VariableInterestEntitiesDeconsolidationGainLoss

2000000

USD

CY2020

us-gaap

Variable Interest Entity Activity Between Vie And Entity Income Or Loss Before Tax

VariableInterestEntityActivityBetweenVIEAndEntityIncomeOrLossBeforeTax

5000000

USD

CY2019

us-gaap

Variable Interest Entity Activity Between Vie And Entity Income Or Loss Before Tax

VariableInterestEntityActivityBetweenVIEAndEntityIncomeOrLossBeforeTax

38000000

USD

CY2018

us-gaap

Variable Interest Entity Activity Between Vie And Entity Income Or Loss Before Tax

VariableInterestEntityActivityBetweenVIEAndEntityIncomeOrLossBeforeTax

3000000

USD

CY2019

us-gaap

Variable Interest Entity Initial Consolidation Gain Or Loss

VariableInterestEntityInitialConsolidationGainOrLoss

15000000

USD

CY2020Q4

us-gaap

Variable Interest Entity Consolidated Carrying Amount Assets

VariableInterestEntityConsolidatedCarryingAmountAssets

292000000

USD

CY2020Q4

us-gaap

Variable Interest Entity Consolidated Carrying Amount Liabilities

VariableInterestEntityConsolidatedCarryingAmountLiabilities

364000000

USD

CY2020Q4

ambc

Deconsolidated Vie Assets

DeconsolidatedVIEAssets

0

USD

CY2020Q4

ambc

Deconsolidated Vie Liabilities

DeconsolidatedVIELiabilities

0

USD

CY2020Q4

us-gaap

Variable Interest Entity Entity Maximum Loss Exposure Amount

VariableInterestEntityEntityMaximumLossExposureAmount

27998000000

USD

CY2020Q4

ambc

Variable Interest Entity Nonconsolidated Carrying Amount Insurance Assets

VariableInterestEntityNonconsolidatedCarryingAmountInsuranceAssets

2314000000

USD

CY2020Q4

ambc

Variable Interest Entity Nonconsolidated Carrying Amount Insurance Liabilities

VariableInterestEntityNonconsolidatedCarryingAmountInsuranceLiabilities

1122000000

USD

CY2020Q4

ambc

Variable Interest Entity Nonconsolidated Carrying Amount Derivative Net Assets Or Liabilities

VariableInterestEntityNonconsolidatedCarryingAmountDerivativeNetAssetsOrLiabilities

8000000

USD

CY2019Q4

us-gaap

Variable Interest Entity Entity Maximum Loss Exposure Amount

VariableInterestEntityEntityMaximumLossExposureAmount

31506000000

USD

CY2019Q4

ambc

Variable Interest Entity Nonconsolidated Carrying Amount Insurance Assets

VariableInterestEntityNonconsolidatedCarryingAmountInsuranceAssets

2247000000

USD

CY2019Q4

ambc

Variable Interest Entity Nonconsolidated Carrying Amount Insurance Liabilities

VariableInterestEntityNonconsolidatedCarryingAmountInsuranceLiabilities

1083000000

USD

CY2020Q4

us-gaap

Equity Method Investments Fair Value Disclosure

EquityMethodInvestmentsFairValueDisclosure

1000000

USD

CY2019Q4

us-gaap

Equity Method Investments Fair Value Disclosure

EquityMethodInvestmentsFairValueDisclosure

3000000

USD

CY2020Q4

us-gaap

Equity Method Investments

EquityMethodInvestments

51000000

USD

CY2019Q4

us-gaap

Equity Method Investments

EquityMethodInvestments

46000000

USD

CY2019Q4

us-gaap

Accumulated Other Comprehensive Income Loss Net Of Tax

AccumulatedOtherComprehensiveIncomeLossNetOfTax

42000000

USD

CY2020

us-gaap

Other Comprehensive Income Loss Before Reclassifications Net Of Tax

OtherComprehensiveIncomeLossBeforeReclassificationsNetOfTax

58000000

USD

CY2020

us-gaap

Reclassification From Accumulated Other Comprehensive Income Current Period Net Of Tax

ReclassificationFromAccumulatedOtherComprehensiveIncomeCurrentPeriodNetOfTax

21000000

USD

CY2020

us-gaap

Other Comprehensive Income Loss Net Of Tax Portion Attributable To Parent

OtherComprehensiveIncomeLossNetOfTaxPortionAttributableToParent

37000000

USD

CY2020Q4

us-gaap

Accumulated Other Comprehensive Income Loss Net Of Tax

AccumulatedOtherComprehensiveIncomeLossNetOfTax

79000000

USD

CY2018Q4

us-gaap

Accumulated Other Comprehensive Income Loss Net Of Tax

AccumulatedOtherComprehensiveIncomeLossNetOfTax

-49000000

USD

CY2019

us-gaap

Other Comprehensive Income Loss Before Reclassifications Net Of Tax

OtherComprehensiveIncomeLossBeforeReclassificationsNetOfTax

168000000

USD

CY2019

us-gaap

Reclassification From Accumulated Other Comprehensive Income Current Period Net Of Tax

ReclassificationFromAccumulatedOtherComprehensiveIncomeCurrentPeriodNetOfTax

78000000

USD

CY2019

us-gaap

Other Comprehensive Income Loss Net Of Tax Portion Attributable To Parent

OtherComprehensiveIncomeLossNetOfTaxPortionAttributableToParent

91000000

USD

CY2019Q4

us-gaap

Accumulated Other Comprehensive Income Loss Net Of Tax

AccumulatedOtherComprehensiveIncomeLossNetOfTax

42000000

USD

CY2020Q4

us-gaap

Common Stock Shares Outstanding

CommonStockSharesOutstanding

45809139

shares

CY2013Q2

us-gaap

Common Stock Par Or Stated Value Per Share

CommonStockParOrStatedValuePerShare

0.01

CY2020Q4

us-gaap

Class Of Warrant Or Right Outstanding

ClassOfWarrantOrRightOutstanding

4877749

shares

CY2013Q2

us-gaap

Class Of Warrant Or Right Exercise Price Of Warrants Or Rights1

ClassOfWarrantOrRightExercisePriceOfWarrantsOrRights1

16.67

CY2020

ambc

Warrant Exercised During Period Shares

WarrantExercisedDuringPeriodShares

34

shares

CY2019

ambc

Warrant Exercised During Period Shares

WarrantExercisedDuringPeriodShares

0

shares

CY2018

ambc

Warrant Exercised During Period Shares

WarrantExercisedDuringPeriodShares

194

shares

CY2020

us-gaap

Stock Issued During Period Shares New Issues

StockIssuedDuringPeriodSharesNewIssues

8

shares

CY2019

us-gaap

Stock Issued During Period Shares New Issues

StockIssuedDuringPeriodSharesNewIssues

0

shares

CY2018

us-gaap

Stock Issued During Period Shares New Issues

StockIssuedDuringPeriodSharesNewIssues

194

shares

CY2015Q2

ambc

First Warrant Buyback Authorization Dollars

FirstWarrantBuybackAuthorizationDollars

10000000

USD

CY2016Q4

ambc

Second Warrant Buy Back Authorized Dollars

SecondWarrantBuyBackAuthorizedDollars

10000000

USD

ambc

Warrants Purchased Shares

WarrantsPurchasedShares

985331

shares

us-gaap

Payments For Repurchase Of Warrants

PaymentsForRepurchaseOfWarrants

8000000

USD

ambc

Warrants Repurchased Average Costper Warrant

WarrantsRepurchasedAverageCostperWarrant

8.21

CY2020Q4

ambc

Remaining Warrant Buy Back Authorized Dollars

RemainingWarrantBuyBackAuthorizedDollars

12000000

USD

CY2018Q3

ambc

Amps Exchange Total Warrants Issued

AMPSExchangeTotalWarrantsIssued

824307

CY2018Q3

ambc

Amps Exchange Total Warrants Issued Cost Per Share

AMPSExchangeTotalWarrantsIssuedCostPerShare

9.72

CY2020

us-gaap

Weighted Average Number Of Shares Outstanding Basic

WeightedAverageNumberOfSharesOutstandingBasic

46147062

shares

CY2019

us-gaap

Weighted Average Number Of Shares Outstanding Basic

WeightedAverageNumberOfSharesOutstandingBasic

45954908

shares

CY2018

us-gaap

Weighted Average Number Of Shares Outstanding Basic

WeightedAverageNumberOfSharesOutstandingBasic

45665883

shares

CY2020

us-gaap

Weighted Average Number Of Diluted Shares Outstanding

WeightedAverageNumberOfDilutedSharesOutstanding

46147062

shares

CY2019

us-gaap

Weighted Average Number Of Diluted Shares Outstanding

WeightedAverageNumberOfDilutedSharesOutstanding

45954908

shares

CY2018

us-gaap

Weighted Average Number Of Diluted Shares Outstanding

WeightedAverageNumberOfDilutedSharesOutstanding

46559835

shares

CY2020Q4

ambc

Financial Guarantee Gross Outstanding Principal

FinancialGuaranteeGrossOutstandingPrincipal

39070000000

USD

CY2019Q4

ambc

Financial Guarantee Gross Outstanding Principal

FinancialGuaranteeGrossOutstandingPrincipal

43908000000

USD

CY2020Q4

us-gaap

Participating Policies Amount In Force

ParticipatingPoliciesAmountInForce

33888000000

USD

CY2019Q4

us-gaap

Participating Policies Amount In Force

ParticipatingPoliciesAmountInForce

38018000000

USD

CY2020Q4

ambc

Financial Guarantee Outstanding Principal Ceded To Third Parties

FinancialGuaranteeOutstandingPrincipalCededToThirdParties

5182000000

USD

CY2020Q4

ambc

Amount Of Insured Par Outstanding Ceded To Reinsurer

AmountOfInsuredParOutstandingCededToReinsurer

2398000000

USD

CY2020

ambc

Ceded Principal Outstanding Major Reinsurer Percentage

CededPrincipalOutstandingMajorReinsurerPercentage

0.061

CY2020Q4

us-gaap

Participating Policies Amount In Force

ParticipatingPoliciesAmountInForce

33888000000

USD

CY2019Q4

us-gaap

Participating Policies Amount In Force

ParticipatingPoliciesAmountInForce

38018000000

USD

CY2020Q4

ambc

Financial Guarantee Gross Outstanding Principal And Interest

FinancialGuaranteeGrossOutstandingPrincipalAndInterest

61895000000

USD

CY2019Q4

ambc

Financial Guarantee Gross Outstanding Principal And Interest

FinancialGuaranteeGrossOutstandingPrincipalAndInterest

69826000000

USD

CY2020Q4

ambc

Net Financial Guarantee Principal And Interest In Force

NetFinancialGuaranteePrincipalAndInterestInForce

51603000000

USD

CY2019Q4

ambc

Net Financial Guarantee Principal And Interest In Force

NetFinancialGuaranteePrincipalAndInterestInForce

58245000000

USD

CY2020

ambc

Percentage Of Highest Single Insured Risk Of Aggregate Net Par Amount Guaranteed

PercentageOfHighestSingleInsuredRiskOfAggregateNetParAmountGuaranteed

0.029

CY2020

us-gaap

Premiums Receivable Note

PremiumsReceivableNote

<div style="text-align:justify"><span style="color:#000000;font-family:'Times New Roman',sans-serif;font-size:9pt;font-weight:400;line-height:120%">Below is the gross premium receivable roll-forward (direct and assumed contracts) for the affected periods:</span></div><div style="margin-bottom:3pt;margin-top:5pt"><table style="border-collapse:collapse;display:inline-table;vertical-align:top;width:99.358%"><tr><td style="width:1.0%"/><td style="width:36.641%"/><td style="width:0.1%"/><td style="width:1.0%"/><td style="width:18.577%"/><td style="width:0.1%"/><td style="width:0.1%"/><td style="width:1.412%"/><td style="width:0.1%"/><td style="width:1.0%"/><td style="width:18.577%"/><td style="width:0.1%"/><td style="width:0.1%"/><td style="width:1.412%"/><td style="width:0.1%"/><td style="width:1.0%"/><td style="width:18.581%"/><td style="width:0.1%"/></tr><tr><td colspan="3" style="padding:2px 1pt;text-align:left;vertical-align:bottom"><div><span style="color:#000000;font-family:'Times New Roman',sans-serif;font-size:8pt;font-weight:700;line-height:100%">Year Ended </span></div><div><span style="color:#000000;font-family:'Times New Roman',sans-serif;font-size:8pt;font-weight:700;line-height:100%">December 31,</span></div></td><td colspan="3" style="padding:2px 1pt;text-align:center;vertical-align:bottom"><span style="color:#000000;font-family:'Times New Roman',sans-serif;font-size:8pt;font-weight:700;line-height:100%">2020</span></td><td colspan="3" style="padding:0 1pt"/><td colspan="3" style="padding:2px 1pt;text-align:center;vertical-align:bottom"><span style="color:#000000;font-family:'Times New Roman',sans-serif;font-size:8pt;font-weight:700;line-height:100%">2019</span></td><td colspan="3" style="padding:0 1pt"/><td colspan="3" style="padding:2px 1pt;text-align:center;vertical-align:bottom"><span style="color:#000000;font-family:'Times New Roman',sans-serif;font-size:8pt;font-weight:700;line-height:100%">2018</span></td></tr><tr><td colspan="3" style="background-color:#cceeff;border-top:1pt solid #000000;padding:2px 1pt;text-align:left;vertical-align:bottom"><span style="color:#000000;font-family:'Times New Roman',sans-serif;font-size:8pt;font-weight:700;line-height:100%">Beginning premium receivable</span></td><td style="background-color:#cceeff;border-top:1pt solid #000000;padding:2px 0 2px 1pt;text-align:left;vertical-align:bottom"><span style="color:#211aff;font-family:'Times New Roman',sans-serif;font-size:8pt;font-weight:700;line-height:100%">$</span></td><td style="background-color:#cceeff;border-top:1pt solid #000000;padding:2px 0;text-align:right;vertical-align:bottom"><span style="color:#211aff;font-family:'Times New Roman',sans-serif;font-size:8pt;font-weight:700;line-height:100%">416</span><span style="color:#211aff;font-family:'Times New Roman',sans-serif;font-size:8pt;font-weight:400;line-height:100%"> </span></td><td style="background-color:#cceeff;border-top:1pt solid #000000;padding:2px 1pt 2px 0;text-align:right;vertical-align:bottom"/><td colspan="3" style="background-color:#cceeff;border-top:1pt solid #000000;padding:0 1pt"/><td style="background-color:#cceeff;border-top:1pt solid #000000;padding:2px 0 2px 1pt;text-align:left;vertical-align:bottom"><span style="color:#000000;font-family:'Times New Roman',sans-serif;font-size:8pt;font-weight:700;line-height:100%">$</span></td><td style="background-color:#cceeff;border-top:1pt solid #000000;padding:2px 0;text-align:right;vertical-align:bottom"><span style="color:#000000;font-family:'Times New Roman',sans-serif;font-size:8pt;font-weight:700;line-height:100%">495</span><span style="color:#000000;font-family:'Times New Roman',sans-serif;font-size:8pt;font-weight:400;line-height:100%"> </span></td><td style="background-color:#cceeff;border-top:1pt solid #000000;padding:2px 1pt 2px 0;text-align:right;vertical-align:bottom"/><td colspan="3" style="background-color:#cceeff;border-top:1pt solid #000000;padding:0 1pt"/><td style="background-color:#cceeff;border-top:1pt solid #000000;padding:2px 0 2px 1pt;text-align:left;vertical-align:bottom"><span style="color:#000000;font-family:'Times New Roman',sans-serif;font-size:8pt;font-weight:700;line-height:100%">$</span></td><td style="background-color:#cceeff;border-top:1pt solid #000000;padding:2px 0;text-align:right;vertical-align:bottom"><span style="color:#000000;font-family:'Times New Roman',sans-serif;font-size:8pt;font-weight:700;line-height:100%">586</span><span style="color:#000000;font-family:'Times New Roman',sans-serif;font-size:8pt;font-weight:400;line-height:100%"> </span></td><td style="background-color:#cceeff;border-top:1pt solid #000000;padding:2px 1pt 2px 0;text-align:right;vertical-align:bottom"/></tr><tr><td colspan="3" style="background-color:#ffffff;padding:2px 1pt 2px 7pt;text-align:left;text-indent:-0.01pt;vertical-align:bottom"><span style="color:#000000;font-family:'Times New Roman',sans-serif;font-size:8pt;font-weight:400;line-height:100%">Adjustment to initially apply ASU 2016-13</span></td><td colspan="2" style="background-color:#ffffff;padding:2px 0 2px 1pt;text-align:right;vertical-align:bottom"><span style="color:#211aff;font-family:'Times New Roman',sans-serif;font-size:8pt;font-weight:700;line-height:100%">(3)</span></td><td style="background-color:#ffffff;padding:2px 1pt 2px 0;text-align:right;vertical-align:bottom"/><td colspan="3" style="background-color:#ffffff;padding:0 1pt"/><td colspan="2" style="background-color:#ffffff;padding:2px 0 2px 1pt;text-align:right;vertical-align:bottom"><span style="color:#000000;font-family:'Times New Roman',sans-serif;font-size:8pt;font-weight:400;line-height:100%">— </span></td><td style="background-color:#ffffff;padding:2px 1pt 2px 0;text-align:right;vertical-align:bottom"/><td colspan="3" style="background-color:#ffffff;padding:0 1pt"/><td colspan="2" style="background-color:#ffffff;padding:2px 0 2px 1pt;text-align:right;vertical-align:bottom"><span style="color:#000000;font-family:'Times New Roman',sans-serif;font-size:8pt;font-weight:400;line-height:100%">— </span></td><td style="background-color:#ffffff;padding:2px 1pt 2px 0;text-align:right;vertical-align:bottom"/></tr><tr><td colspan="3" style="background-color:#cceeff;padding:2px 1pt 2px 7pt;text-align:left;vertical-align:bottom"><span style="color:#000000;font-family:'Times New Roman',sans-serif;font-size:8pt;font-weight:400;line-height:100%">Premium receipts</span></td><td colspan="2" style="background-color:#cceeff;padding:2px 0 2px 1pt;text-align:right;vertical-align:bottom"><span style="color:#211aff;font-family:'Times New Roman',sans-serif;font-size:8pt;font-weight:700;line-height:100%">(46)</span></td><td style="background-color:#cceeff;padding:2px 1pt 2px 0;text-align:right;vertical-align:bottom"/><td colspan="3" style="background-color:#cceeff;padding:0 1pt"/><td colspan="2" style="background-color:#cceeff;padding:2px 0 2px 1pt;text-align:right;vertical-align:bottom"><span style="color:#000000;font-family:'Times New Roman',sans-serif;font-size:8pt;font-weight:400;line-height:100%">(48)</span></td><td style="background-color:#cceeff;padding:2px 1pt 2px 0;text-align:right;vertical-align:bottom"/><td colspan="3" style="background-color:#cceeff;padding:0 1pt"/><td colspan="2" style="background-color:#cceeff;padding:2px 0 2px 1pt;text-align:right;vertical-align:bottom"><span style="color:#000000;font-family:'Times New Roman',sans-serif;font-size:8pt;font-weight:400;line-height:100%">(56)</span></td><td style="background-color:#cceeff;padding:2px 1pt 2px 0;text-align:right;vertical-align:bottom"/></tr><tr><td colspan="3" style="background-color:#ffffff;padding:2px 1pt;text-align:left;vertical-align:bottom"><div style="padding-left:6pt;text-indent:-0.01pt"><span style="color:#000000;font-family:'Times New Roman',sans-serif;font-size:8pt;font-weight:400;line-height:100%">Adjustments for changes in expected and contractual cash flows </span><span style="color:#000000;font-family:'Times New Roman',sans-serif;font-size:5.2pt;font-weight:400;line-height:100%;position:relative;top:-2.8pt;vertical-align:baseline">(1)</span></div></td><td colspan="2" style="background-color:#ffffff;padding:2px 0 2px 1pt;text-align:right;vertical-align:bottom"><span style="color:#211aff;font-family:'Times New Roman',sans-serif;font-size:8pt;font-weight:700;line-height:100%">(6)</span></td><td style="background-color:#ffffff;padding:2px 1pt 2px 0;text-align:right;vertical-align:bottom"/><td colspan="3" style="background-color:#ffffff;padding:0 1pt"/><td colspan="2" style="background-color:#ffffff;padding:2px 0 2px 1pt;text-align:right;vertical-align:bottom"><span style="color:#000000;font-family:'Times New Roman',sans-serif;font-size:8pt;font-weight:400;line-height:100%">(38)</span></td><td style="background-color:#ffffff;padding:2px 1pt 2px 0;text-align:right;vertical-align:bottom"/><td colspan="3" style="background-color:#ffffff;padding:0 1pt"/><td colspan="2" style="background-color:#ffffff;padding:2px 0 2px 1pt;text-align:right;vertical-align:bottom"><span style="color:#000000;font-family:'Times New Roman',sans-serif;font-size:8pt;font-weight:400;line-height:100%">(42)</span></td><td style="background-color:#ffffff;padding:2px 1pt 2px 0;text-align:right;vertical-align:bottom"/></tr><tr><td colspan="3" style="background-color:#cceeff;padding:2px 1pt 2px 7pt;text-align:left;vertical-align:bottom"><span style="color:#000000;font-family:'Times New Roman',sans-serif;font-size:8pt;font-weight:400;line-height:100%">Accretion of premium receivable discount</span></td><td colspan="2" style="background-color:#cceeff;padding:2px 0 2px 1pt;text-align:right;vertical-align:bottom"><span style="color:#211aff;font-family:'Times New Roman',sans-serif;font-size:8pt;font-weight:700;line-height:100%">9</span><span style="color:#211aff;font-family:'Times New Roman',sans-serif;font-size:8pt;font-weight:400;line-height:100%"> </span></td><td style="background-color:#cceeff;padding:2px 1pt 2px 0;text-align:right;vertical-align:bottom"/><td colspan="3" style="background-color:#cceeff;padding:0 1pt"/><td colspan="2" style="background-color:#cceeff;padding:2px 0 2px 1pt;text-align:right;vertical-align:bottom"><span style="color:#000000;font-family:'Times New Roman',sans-serif;font-size:8pt;font-weight:400;line-height:100%">11 </span></td><td style="background-color:#cceeff;padding:2px 1pt 2px 0;text-align:right;vertical-align:bottom"/><td colspan="3" style="background-color:#cceeff;padding:0 1pt"/><td colspan="2" style="background-color:#cceeff;padding:2px 0 2px 1pt;text-align:right;vertical-align:bottom"><span style="color:#000000;font-family:'Times New Roman',sans-serif;font-size:8pt;font-weight:400;line-height:100%">15 </span></td><td style="background-color:#cceeff;padding:2px 1pt 2px 0;text-align:right;vertical-align:bottom"/></tr><tr><td colspan="3" style="background-color:#ffffff;padding:2px 1pt 2px 7pt;text-align:left;vertical-align:bottom"><span style="color:#000000;font-family:'Times New Roman',sans-serif;font-size:8pt;font-weight:400;line-height:100%">Deconsolidation of certain VIEs</span></td><td colspan="2" style="background-color:#ffffff;padding:2px 0 2px 1pt;text-align:right;vertical-align:bottom"><span style="color:#211aff;font-family:'Times New Roman',sans-serif;font-size:8pt;font-weight:700;line-height:100%">—</span><span style="color:#211aff;font-family:'Times New Roman',sans-serif;font-size:8pt;font-weight:400;line-height:100%"> </span></td><td style="background-color:#ffffff;padding:2px 1pt 2px 0;text-align:right;vertical-align:bottom"/><td colspan="3" style="background-color:#ffffff;padding:0 1pt"/><td colspan="2" style="background-color:#ffffff;padding:2px 0 2px 1pt;text-align:right;vertical-align:bottom"><span style="color:#000000;font-family:'Times New Roman',sans-serif;font-size:8pt;font-weight:400;line-height:100%">3 </span></td><td style="background-color:#ffffff;padding:2px 1pt 2px 0;text-align:right;vertical-align:bottom"/><td colspan="3" style="background-color:#ffffff;padding:0 1pt"/><td colspan="2" style="background-color:#ffffff;padding:2px 0 2px 1pt;text-align:right;vertical-align:bottom"><span style="color:#000000;font-family:'Times New Roman',sans-serif;font-size:8pt;font-weight:400;line-height:100%">— </span></td><td style="background-color:#ffffff;padding:2px 1pt 2px 0;text-align:right;vertical-align:bottom"/></tr><tr><td colspan="3" style="background-color:#cceeff;padding:2px 1pt 2px 7pt;text-align:left;text-indent:-0.01pt;vertical-align:bottom"><span style="color:#000000;font-family:'Times New Roman',sans-serif;font-size:8pt;font-weight:400;line-height:100%">Changes to allowance for credit losses</span></td><td colspan="2" style="background-color:#cceeff;padding:2px 0 2px 1pt;text-align:right;vertical-align:bottom"><span style="color:#211aff;font-family:'Times New Roman',sans-serif;font-size:8pt;font-weight:700;line-height:100%">(4)</span></td><td style="background-color:#cceeff;padding:2px 1pt 2px 0;text-align:right;vertical-align:bottom"/><td colspan="3" style="background-color:#cceeff;padding:0 1pt"/><td colspan="2" style="background-color:#cceeff;padding:2px 0 2px 1pt;text-align:right;vertical-align:bottom"><span style="color:#000000;font-family:'Times New Roman',sans-serif;font-size:8pt;font-weight:400;line-height:100%">(2)</span></td><td style="background-color:#cceeff;padding:2px 1pt 2px 0;text-align:right;vertical-align:bottom"/><td colspan="3" style="background-color:#cceeff;padding:0 1pt"/><td colspan="2" style="background-color:#cceeff;padding:2px 0 2px 1pt;text-align:right;vertical-align:bottom"><span style="color:#000000;font-family:'Times New Roman',sans-serif;font-size:8pt;font-weight:400;line-height:100%">2 </span></td><td style="background-color:#cceeff;padding:2px 1pt 2px 0;text-align:right;vertical-align:bottom"/></tr><tr><td colspan="3" style="background-color:#ffffff;padding:2px 1pt 2px 7pt;text-align:left;vertical-align:bottom"><span style="color:#000000;font-family:'Times New Roman',sans-serif;font-size:8pt;font-weight:400;line-height:100%">Other adjustments (including foreign exchange)</span></td><td colspan="2" style="background-color:#ffffff;padding:2px 0 2px 1pt;text-align:right;vertical-align:bottom"><span style="color:#211aff;font-family:'Times New Roman',sans-serif;font-size:8pt;font-weight:700;line-height:100%">5</span><span style="color:#211aff;font-family:'Times New Roman',sans-serif;font-size:8pt;font-weight:400;line-height:100%"> </span></td><td style="background-color:#ffffff;padding:2px 1pt 2px 0;text-align:right;vertical-align:bottom"/><td colspan="3" style="background-color:#ffffff;padding:0 1pt"/><td colspan="2" style="background-color:#ffffff;padding:2px 0 2px 1pt;text-align:right;vertical-align:bottom"><span style="color:#000000;font-family:'Times New Roman',sans-serif;font-size:8pt;font-weight:400;line-height:100%">(6)</span></td><td style="background-color:#ffffff;padding:2px 1pt 2px 0;text-align:right;vertical-align:bottom"/><td colspan="3" style="background-color:#ffffff;padding:0 1pt"/><td colspan="2" style="background-color:#ffffff;padding:2px 0 2px 1pt;text-align:right;vertical-align:bottom"><span style="color:#000000;font-family:'Times New Roman',sans-serif;font-size:8pt;font-weight:400;line-height:100%">(10)</span></td><td style="background-color:#ffffff;padding:2px 1pt 2px 0;text-align:right;vertical-align:bottom"/></tr><tr><td colspan="3" style="background-color:#cceeff;border-bottom:3pt double #000000;border-top:1pt solid #000000;padding:2px 1pt;text-align:left;vertical-align:bottom"><div><span style="color:#000000;font-family:'Times New Roman',sans-serif;font-size:8pt;font-weight:700;line-height:100%">Ending premium receivable </span><span style="color:#000000;font-family:'Times New Roman',sans-serif;font-size:5.2pt;font-weight:700;line-height:100%;position:relative;top:-2.8pt;vertical-align:baseline">(2)</span></div></td><td style="background-color:#cceeff;border-bottom:3pt double #000000;border-top:1pt solid #000000;padding:2px 0 2px 1pt;text-align:left;vertical-align:bottom"><span style="color:#211aff;font-family:'Times New Roman',sans-serif;font-size:8pt;font-weight:700;line-height:100%">$</span></td><td style="background-color:#cceeff;border-bottom:3pt double #000000;border-top:1pt solid #000000;padding:2px 0;text-align:right;vertical-align:bottom"><span style="color:#211aff;font-family:'Times New Roman',sans-serif;font-size:8pt;font-weight:700;line-height:100%">370</span><span style="color:#211aff;font-family:'Times New Roman',sans-serif;font-size:8pt;font-weight:400;line-height:100%"> </span></td><td style="background-color:#cceeff;border-bottom:3pt double #000000;border-top:1pt solid #000000;padding:2px 1pt 2px 0;text-align:right;vertical-align:bottom"/><td colspan="3" style="background-color:#cceeff;border-bottom:3pt double #000000;border-top:1pt solid #000000;padding:0 1pt"/><td style="background-color:#cceeff;border-bottom:3pt double #000000;border-top:1pt solid #000000;padding:2px 0 2px 1pt;text-align:left;vertical-align:bottom"><span style="color:#000000;font-family:'Times New Roman',sans-serif;font-size:8pt;font-weight:700;line-height:100%">$</span></td><td style="background-color:#cceeff;border-bottom:3pt double #000000;border-top:1pt solid #000000;padding:2px 0;text-align:right;vertical-align:bottom"><span style="color:#000000;font-family:'Times New Roman',sans-serif;font-size:8pt;font-weight:700;line-height:100%">416</span><span style="color:#000000;font-family:'Times New Roman',sans-serif;font-size:8pt;font-weight:400;line-height:100%"> </span></td><td style="background-color:#cceeff;border-bottom:3pt double #000000;border-top:1pt solid #000000;padding:2px 1pt 2px 0;text-align:right;vertical-align:bottom"/><td colspan="3" style="background-color:#cceeff;border-bottom:3pt double #000000;border-top:1pt solid #000000;padding:0 1pt"/><td style="background-color:#cceeff;border-bottom:3pt double #000000;border-top:1pt solid #000000;padding:2px 0 2px 1pt;text-align:left;vertical-align:bottom"><span style="color:#000000;font-family:'Times New Roman',sans-serif;font-size:8pt;font-weight:700;line-height:100%">$</span></td><td style="background-color:#cceeff;border-bottom:3pt double #000000;border-top:1pt solid #000000;padding:2px 0;text-align:right;vertical-align:bottom"><span style="color:#000000;font-family:'Times New Roman',sans-serif;font-size:8pt;font-weight:700;line-height:100%">495</span><span style="color:#000000;font-family:'Times New Roman',sans-serif;font-size:8pt;font-weight:400;line-height:100%"> </span></td><td style="background-color:#cceeff;border-bottom:3pt double #000000;border-top:1pt solid #000000;padding:2px 1pt 2px 0;text-align:right;vertical-align:bottom"/></tr></table></div><span style="color:#000000;font-family:'Times New Roman',sans-serif;font-size:8pt;font-weight:400;line-height:120%">(1)</span><span style="color:#000000;font-family:'Times New Roman',sans-serif;font-size:8pt;font-weight:400;line-height:120%;padding-left:8.68pt">Adjustments for changes in expected and contractual cash flows primarily due to reductions in insured exposure as a result of early policy terminations and unscheduled principal paydowns.</span>(2)Premium receivable includes premiums to be received in foreign denominated currencies most notably in British Pounds and Euros. At December 31, 2020, 2019 and 2018 premium receivables include British Pounds of $117 (£86), $129 (£97) and $131 (£103), respectively, and Euros of $19 (€16), $26 (€23) and $31 (€27), respectively.

CY2019Q4

us-gaap

Financial Guarantee Insurance Contracts Premium Receivable

FinancialGuaranteeInsuranceContractsPremiumReceivable

416000000

USD

CY2018Q4

us-gaap

Financial Guarantee Insurance Contracts Premium Receivable

FinancialGuaranteeInsuranceContractsPremiumReceivable

495000000

USD

CY2017Q4

us-gaap

Financial Guarantee Insurance Contracts Premium Receivable

FinancialGuaranteeInsuranceContractsPremiumReceivable

586000000

USD

CY2020

us-gaap

Financial Guarantee Insurance Contracts Premium Receivable Proceeds From Premiums Received

FinancialGuaranteeInsuranceContractsPremiumReceivableProceedsFromPremiumsReceived

-46000000

USD

CY2019

us-gaap

Financial Guarantee Insurance Contracts Premium Receivable Proceeds From Premiums Received

FinancialGuaranteeInsuranceContractsPremiumReceivableProceedsFromPremiumsReceived

-48000000

USD

CY2018

us-gaap

Financial Guarantee Insurance Contracts Premium Receivable Proceeds From Premiums Received

FinancialGuaranteeInsuranceContractsPremiumReceivableProceedsFromPremiumsReceived

56000000

USD

CY2020

us-gaap

Financial Guarantee Insurance Contracts Premiums Receivable Adjustment Change In Period Of Contract

FinancialGuaranteeInsuranceContractsPremiumsReceivableAdjustmentChangeInPeriodOfContract

-6000000

USD

CY2019

us-gaap

Financial Guarantee Insurance Contracts Premiums Receivable Adjustment Change In Period Of Contract

FinancialGuaranteeInsuranceContractsPremiumsReceivableAdjustmentChangeInPeriodOfContract

-38000000

USD

CY2018

us-gaap

Financial Guarantee Insurance Contracts Premiums Receivable Adjustment Change In Period Of Contract

FinancialGuaranteeInsuranceContractsPremiumsReceivableAdjustmentChangeInPeriodOfContract

-42000000

USD

CY2020

us-gaap

Financial Guarantee Insurance Contracts Premiums Receivable Accretion Of Discount On Premium Receivable

FinancialGuaranteeInsuranceContractsPremiumsReceivableAccretionOfDiscountOnPremiumReceivable

9000000

USD

CY2019

us-gaap

Financial Guarantee Insurance Contracts Premiums Receivable Accretion Of Discount On Premium Receivable

FinancialGuaranteeInsuranceContractsPremiumsReceivableAccretionOfDiscountOnPremiumReceivable

11000000

USD

CY2018

us-gaap

Financial Guarantee Insurance Contracts Premiums Receivable Accretion Of Discount On Premium Receivable

FinancialGuaranteeInsuranceContractsPremiumsReceivableAccretionOfDiscountOnPremiumReceivable

15000000

USD

CY2020

ambc

Financial Guarantee Insurance Contracts Premium Receivable Deconsolidationof Vie

FinancialGuaranteeInsuranceContractsPremiumReceivableDeconsolidationofVIE

0

USD

CY2019

ambc

Financial Guarantee Insurance Contracts Premium Receivable Deconsolidationof Vie

FinancialGuaranteeInsuranceContractsPremiumReceivableDeconsolidationofVIE

3000000

USD

CY2020

us-gaap

Allowance For Doubtful Accounts Receivable Period Increase Decrease

AllowanceForDoubtfulAccountsReceivablePeriodIncreaseDecrease

-4000000

USD

CY2019

us-gaap

Allowance For Doubtful Accounts Receivable Period Increase Decrease

AllowanceForDoubtfulAccountsReceivablePeriodIncreaseDecrease

-2000000

USD

CY2018

us-gaap

Allowance For Doubtful Accounts Receivable Period Increase Decrease

AllowanceForDoubtfulAccountsReceivablePeriodIncreaseDecrease

2000000

USD

CY2020

us-gaap

Financial Guarantee Insurance Contracts Premiums Receivable Adjustment Other Adjustments

FinancialGuaranteeInsuranceContractsPremiumsReceivableAdjustmentOtherAdjustments

5000000

USD

CY2019

us-gaap

Financial Guarantee Insurance Contracts Premiums Receivable Adjustment Other Adjustments

FinancialGuaranteeInsuranceContractsPremiumsReceivableAdjustmentOtherAdjustments

-6000000

USD

CY2018

us-gaap

Financial Guarantee Insurance Contracts Premiums Receivable Adjustment Other Adjustments

FinancialGuaranteeInsuranceContractsPremiumsReceivableAdjustmentOtherAdjustments

-10000000

USD

CY2020Q4

us-gaap

Financial Guarantee Insurance Contracts Premium Receivable

FinancialGuaranteeInsuranceContractsPremiumReceivable

370000000

USD

CY2019Q4

us-gaap

Financial Guarantee Insurance Contracts Premium Receivable

FinancialGuaranteeInsuranceContractsPremiumReceivable

416000000

USD

CY2018Q4

us-gaap

Financial Guarantee Insurance Contracts Premium Receivable

FinancialGuaranteeInsuranceContractsPremiumReceivable

495000000

USD

CY2020

us-gaap

Direct Premiums Written

DirectPremiumsWritten

-1000000

USD

CY2020

us-gaap

Assumed Premiums Written

AssumedPremiumsWritten

0

USD

CY2020

us-gaap

Ceded Premiums Written

CededPremiumsWritten

-1000000

USD

CY2020

us-gaap

Premiums Written Net

PremiumsWrittenNet

0

USD

CY2020

us-gaap

Direct Premiums Earned

DirectPremiumsEarned

65000000

USD

CY2020

us-gaap

Assumed Premiums Earned

AssumedPremiumsEarned

1000000

USD

CY2020

us-gaap

Ceded Premiums Earned

CededPremiumsEarned

12000000

USD

CY2020

us-gaap

Premiums Earned Net

PremiumsEarnedNet

54000000

USD

CY2019

us-gaap

Direct Premiums Written

DirectPremiumsWritten

-28000000

USD

CY2019

us-gaap

Assumed Premiums Written

AssumedPremiumsWritten

0

USD

CY2019

us-gaap

Ceded Premiums Written

CededPremiumsWritten

31000000

USD

CY2019

us-gaap

Premiums Written Net

PremiumsWrittenNet

-60000000

USD

CY2019

us-gaap

Direct Premiums Earned

DirectPremiumsEarned

75000000

USD

CY2019

us-gaap

Assumed Premiums Earned

AssumedPremiumsEarned

0

USD

CY2019

us-gaap

Ceded Premiums Earned

CededPremiumsEarned

10000000

USD

CY2019

us-gaap

Premiums Earned Net

PremiumsEarnedNet

66000000

USD

CY2018

us-gaap

Direct Premiums Written

DirectPremiumsWritten

-24000000

USD

CY2018

us-gaap

Assumed Premiums Written

AssumedPremiumsWritten

0

USD

CY2018

us-gaap

Ceded Premiums Written

CededPremiumsWritten

17000000

USD

CY2018

us-gaap

Premiums Written Net

PremiumsWrittenNet

-41000000

USD

CY2018

us-gaap

Direct Premiums Earned

DirectPremiumsEarned

119000000

USD

CY2018

us-gaap

Assumed Premiums Earned

AssumedPremiumsEarned

0

USD

CY2018

us-gaap

Ceded Premiums Earned

CededPremiumsEarned

8000000

USD

CY2018

us-gaap

Premiums Earned Net

PremiumsEarnedNet

111000000

USD

CY2020

us-gaap

Financial Guarantee Insurance Contracts Accelerated Premium Revenue Amount

FinancialGuaranteeInsuranceContractsAcceleratedPremiumRevenueAmount

12000000

USD

CY2019

us-gaap

Financial Guarantee Insurance Contracts Accelerated Premium Revenue Amount

FinancialGuaranteeInsuranceContractsAcceleratedPremiumRevenueAmount

10000000

USD

CY2018

us-gaap

Financial Guarantee Insurance Contracts Accelerated Premium Revenue Amount

FinancialGuaranteeInsuranceContractsAcceleratedPremiumRevenueAmount

32000000

USD

CY2020

us-gaap

Premiums Earned Net Financial Guarantee Insurance Contracts

PremiumsEarnedNetFinancialGuaranteeInsuranceContracts

54000000

USD

CY2019

us-gaap

Premiums Earned Net Financial Guarantee Insurance Contracts

PremiumsEarnedNetFinancialGuaranteeInsuranceContracts

66000000

USD

CY2018

us-gaap

Premiums Earned Net Financial Guarantee Insurance Contracts

PremiumsEarnedNetFinancialGuaranteeInsuranceContracts

111000000

USD

CY2020Q4

us-gaap

Financial Guarantee Insurance Contracts Premium Expected To Be Collected During First Quarter Following Balance Sheet Date

FinancialGuaranteeInsuranceContractsPremiumExpectedToBeCollectedDuringFirstQuarterFollowingBalanceSheetDate

12000000

USD

CY2020Q4

us-gaap

Financial Guarantee Insurance Contracts Future Expected Premium Revenue To Be Recognized During First Quarter Following Balance Sheet Date

FinancialGuaranteeInsuranceContractsFutureExpectedPremiumRevenueToBeRecognizedDuringFirstQuarterFollowingBalanceSheetDate

9000000

USD

CY2020Q4

us-gaap

Financial Guarantee Insurance Contracts Premium Expected To Be Collected During Second Quarter Following The Balance Sheet Date

FinancialGuaranteeInsuranceContractsPremiumExpectedToBeCollectedDuringSecondQuarterFollowingTheBalanceSheetDate

8000000

USD

CY2020Q4

us-gaap

Financial Guarantee Insurance Contracts Future Expected Premium Revenue To Be Recognized During Second Quarter Following Balance Sheet Date

FinancialGuaranteeInsuranceContractsFutureExpectedPremiumRevenueToBeRecognizedDuringSecondQuarterFollowingBalanceSheetDate

9000000

USD

CY2020Q4

us-gaap

Financial Guarantee Insurance Contracts Premium Expected To Be Collected During Third Quarter Following Balance Sheet Date

FinancialGuaranteeInsuranceContractsPremiumExpectedToBeCollectedDuringThirdQuarterFollowingBalanceSheetDate

9000000

USD

CY2020Q4

us-gaap

Financial Guarantee Insurance Contracts Future Expected Premium Revenue To Be Recognized During Third Quarter Following Balance Sheet Date

FinancialGuaranteeInsuranceContractsFutureExpectedPremiumRevenueToBeRecognizedDuringThirdQuarterFollowingBalanceSheetDate

9000000

USD

CY2020Q4

us-gaap

Financial Guarantee Insurance Contracts Premium Expected To Be Collected During Fourth Quarter Following Balance Sheet Date

FinancialGuaranteeInsuranceContractsPremiumExpectedToBeCollectedDuringFourthQuarterFollowingBalanceSheetDate

8000000

USD

CY2020Q4

us-gaap

Financial Guarantee Insurance Contracts Future Expected Premium Revenue To Be Recognized During Fourth Quarter Following Balance Sheet Date

FinancialGuaranteeInsuranceContractsFutureExpectedPremiumRevenueToBeRecognizedDuringFourthQuarterFollowingBalanceSheetDate

9000000

USD

CY2020Q4

us-gaap

Financial Guarantee Insurance Contracts Premium Expected To Be Collected More Than One And Within Two Years From Balance Sheet Date

FinancialGuaranteeInsuranceContractsPremiumExpectedToBeCollectedMoreThanOneAndWithinTwoYearsFromBalanceSheetDate

36000000

USD

CY2020Q4

us-gaap

Financial Guarantee Insurance Contracts Future Expected Premium Revenue To Be Recognized More Than One And Within Two Years From Balance Sheet Date

FinancialGuaranteeInsuranceContractsFutureExpectedPremiumRevenueToBeRecognizedMoreThanOneAndWithinTwoYearsFromBalanceSheetDate

33000000

USD

CY2020Q4

us-gaap

Financial Guarantee Insurance Contracts Premium Expected To Be Collected More Than Two And Within Three Years From Balance Sheet Date

FinancialGuaranteeInsuranceContractsPremiumExpectedToBeCollectedMoreThanTwoAndWithinThreeYearsFromBalanceSheetDate

34000000

USD

CY2020Q4

us-gaap

Financial Guarantee Insurance Contracts Future Expected Premium Revenue To Be Recognized More Than Two And Within Three Years From Balance Sheet Date

FinancialGuaranteeInsuranceContractsFutureExpectedPremiumRevenueToBeRecognizedMoreThanTwoAndWithinThreeYearsFromBalanceSheetDate

31000000

USD

CY2020Q4

us-gaap

Financial Guarantee Insurance Contracts Premium Expected To Be Collected More Than Three And Within Four Years From Balance Sheet Date

FinancialGuaranteeInsuranceContractsPremiumExpectedToBeCollectedMoreThanThreeAndWithinFourYearsFromBalanceSheetDate

33000000

USD

CY2020Q4

us-gaap

Financial Guarantee Insurance Contracts Future Expected Premium Revenue To Be Recognized More Than Three And Within Four Years From Balance Sheet Date

FinancialGuaranteeInsuranceContractsFutureExpectedPremiumRevenueToBeRecognizedMoreThanThreeAndWithinFourYearsFromBalanceSheetDate

29000000

USD

CY2020Q4

us-gaap

Financial Guarantee Insurance Contracts Premium Expected To Be Collected More Than Four And Within Five Years From Balance Sheet Date

FinancialGuaranteeInsuranceContractsPremiumExpectedToBeCollectedMoreThanFourAndWithinFiveYearsFromBalanceSheetDate

31000000

USD

CY2020Q4

us-gaap

Financial Guarantee Insurance Contracts Future Expected Premium Revenue To Be Recognized More Than Four And Within Five Years From Balance Sheet Date

FinancialGuaranteeInsuranceContractsFutureExpectedPremiumRevenueToBeRecognizedMoreThanFourAndWithinFiveYearsFromBalanceSheetDate

27000000

USD

CY2020Q4

us-gaap

Financial Guarantee Insurance Contracts Premium Expected To Be Collected More Than Five And Within10 Years From Balance Sheet Date

FinancialGuaranteeInsuranceContractsPremiumExpectedToBeCollectedMoreThanFiveAndWithin10YearsFromBalanceSheetDate

132000000

USD

CY2020Q4

us-gaap

Financial Guarantee Insurance Contracts Future Expected Premium Revenue To Be Recognized More Than Five And Within10 Years From Balance Sheet Date

FinancialGuaranteeInsuranceContractsFutureExpectedPremiumRevenueToBeRecognizedMoreThanFiveAndWithin10YearsFromBalanceSheetDate

113000000

USD

CY2020Q4

us-gaap

Financial Guarantee Insurance Contracts Premium Expected To Be Collected More Than10 And Within15 Years From Balance Sheet Date

FinancialGuaranteeInsuranceContractsPremiumExpectedToBeCollectedMoreThan10AndWithin15YearsFromBalanceSheetDate

91000000

USD

CY2020Q4

us-gaap

Financial Guarantee Insurance Contracts Future Expected Premium Revenue To Be Recognized More Than10 And Within15 Years From Balance Sheet Date

FinancialGuaranteeInsuranceContractsFutureExpectedPremiumRevenueToBeRecognizedMoreThan10AndWithin15YearsFromBalanceSheetDate

72000000

USD

CY2020Q4

us-gaap

Financial Guarantee Insurance Contracts Premium Expected To Be Collected More Than15 And Within20 Years From Balance Sheet Date

FinancialGuaranteeInsuranceContractsPremiumExpectedToBeCollectedMoreThan15AndWithin20YearsFromBalanceSheetDate

42000000

USD

CY2020Q4

us-gaap

Financial Guarantee Insurance Contracts Future Expected Premium Revenue To Be Recognized More Than15 And Within20 Years From Balance Sheet Date

FinancialGuaranteeInsuranceContractsFutureExpectedPremiumRevenueToBeRecognizedMoreThan15AndWithin20YearsFromBalanceSheetDate

30000000

USD

CY2020Q4

us-gaap

Financial Guarantee Insurance Contracts Premium Expected To Be Collected More Than20 And Within25 Years From Balance Sheet Date

FinancialGuaranteeInsuranceContractsPremiumExpectedToBeCollectedMoreThan20AndWithin25YearsFromBalanceSheetDate

19000000

USD

CY2020Q4

us-gaap

Financial Guarantee Insurance Contracts Future Expected Premium Revenue To Be Recognized More Than20 And Within25 Years From Balance Sheet Date

FinancialGuaranteeInsuranceContractsFutureExpectedPremiumRevenueToBeRecognizedMoreThan20AndWithin25YearsFromBalanceSheetDate

12000000

USD

CY2020Q4

us-gaap

Financial Guarantee Insurance Contracts Premium Expected To Be Collected More Than25 And Within30 Years From Balance Sheet Date

FinancialGuaranteeInsuranceContractsPremiumExpectedToBeCollectedMoreThan25AndWithin30YearsFromBalanceSheetDate

7000000

USD

CY2020Q4

us-gaap

Financial Guarantee Insurance Contracts Future Expected Premium Revenue To Be Recognized More Than25 And Within30 Years From Balance Sheet Date

FinancialGuaranteeInsuranceContractsFutureExpectedPremiumRevenueToBeRecognizedMoreThan25AndWithin30YearsFromBalanceSheetDate

4000000

USD

CY2020Q4

us-gaap

Financial Guarantee Insurance Contracts Premium Expected To Be Collected More Than30 And Within35 Years From Balance Sheet Date

FinancialGuaranteeInsuranceContractsPremiumExpectedToBeCollectedMoreThan30AndWithin35YearsFromBalanceSheetDate

1000000

USD

CY2020Q4

us-gaap

Financial Guarantee Insurance Contracts Future Expected Premium Revenue To Be Recognized More Than30 And Within35 Years From Balance Sheet Date

FinancialGuaranteeInsuranceContractsFutureExpectedPremiumRevenueToBeRecognizedMoreThan30AndWithin35YearsFromBalanceSheetDate

0

USD

CY2020Q4

us-gaap

Financial Guarantee Insurance Contracts Premium Receivable Premium Expected To Be Collected

FinancialGuaranteeInsuranceContractsPremiumReceivablePremiumExpectedToBeCollected

462000000

USD

CY2020Q4

us-gaap

Financial Guarantee Insurance Contracts Future Expected Premium Revenue To Be Recognized

FinancialGuaranteeInsuranceContractsFutureExpectedPremiumRevenueToBeRecognized

386000000

USD

CY2020Q4

us-gaap

Premiums Receivable Gross

PremiumsReceivableGross

387000000

USD

CY2019Q4

us-gaap

Allowance For Doubtful Accounts Premiums And Other Receivables

AllowanceForDoubtfulAccountsPremiumsAndOtherReceivables

9000000

USD

CY2020

us-gaap

Premium Receivable Credit Loss Expense Reversal

PremiumReceivableCreditLossExpenseReversal

9000000

USD

CY2020

us-gaap

Premiums Receivable Allowance For Doubtful Accounts Write Offs Against Allowance

PremiumsReceivableAllowanceForDoubtfulAccountsWriteOffsAgainstAllowance

-2000000

USD

CY2020

us-gaap

Premiums Receivable Allowance For Doubtful Accounts Recoveries

PremiumsReceivableAllowanceForDoubtfulAccountsRecoveries

0

USD

CY2020Q4

us-gaap

Allowance For Doubtful Accounts Premiums And Other Receivables

AllowanceForDoubtfulAccountsPremiumsAndOtherReceivables

17000000

USD

CY2019Q4

us-gaap

Allowance For Doubtful Accounts Premiums And Other Receivables

AllowanceForDoubtfulAccountsPremiumsAndOtherReceivables

9000000

USD

CY2020Q4

us-gaap

Financing Receivable Recorded Investment Past Due

FinancingReceivableRecordedInvestmentPastDue

0

USD

CY2020Q4

us-gaap

Financing Receivable Recorded Investment90 Days Past Due And Still Accruing

FinancingReceivableRecordedInvestment90DaysPastDueAndStillAccruing

0

USD

CY2020Q4

us-gaap

Liability Net For Claims And Claims Adjustment Expense Financial Guarantee Insurance Contracts

LiabilityNetForClaimsAndClaimsAdjustmentExpenseFinancialGuaranteeInsuranceContracts

1759000000

USD

CY2020Q4

us-gaap

Salvage And Subrogation Recoveries Value

SalvageAndSubrogationRecoveriesValue

2156000000

USD

CY2020Q4

us-gaap

Schedule Of Insured Financial Obligations With Credit Deterioration Statement Of Financial Position Claim Liability

ScheduleOfInsuredFinancialObligationsWithCreditDeteriorationStatementOfFinancialPositionClaimLiability

-397000000

USD

CY2019Q4

us-gaap

Liability Net For Claims And Claims Adjustment Expense Financial Guarantee Insurance Contracts

LiabilityNetForClaimsAndClaimsAdjustmentExpenseFinancialGuaranteeInsuranceContracts

1548000000

USD

CY2019Q4

us-gaap

Salvage And Subrogation Recoveries Value

SalvageAndSubrogationRecoveriesValue

2029000000

USD

CY2019Q4

us-gaap

Schedule Of Insured Financial Obligations With Credit Deterioration Statement Of Financial Position Claim Liability

ScheduleOfInsuredFinancialObligationsWithCreditDeteriorationStatementOfFinancialPositionClaimLiability

-482000000

USD

CY2020

us-gaap

Schedule Of Liability For Unpaid Claims And Claims Adjustment Expense

ScheduleOfLiabilityForUnpaidClaimsAndClaimsAdjustmentExpense

<div style="text-align:justify"><span style="color:#000000;font-family:'Times New Roman',sans-serif;font-size:9pt;font-weight:400;line-height:120%">Below is the loss and loss expense reserve roll-forward, net of subrogation recoverable and reinsurance, for the affected periods.</span></div><div style="margin-bottom:5pt;margin-top:9pt;padding-left:18pt;text-align:right"><table style="border-collapse:collapse;display:inline-table;vertical-align:top;width:99.679%"><tr><td style="width:1.0%"/><td style="width:41.665%"/><td style="width:0.1%"/><td style="width:1.0%"/><td style="width:16.906%"/><td style="width:0.1%"/><td style="width:0.1%"/><td style="width:1.407%"/><td style="width:0.1%"/><td style="width:1.0%"/><td style="width:16.906%"/><td style="width:0.1%"/><td style="width:0.1%"/><td style="width:1.407%"/><td style="width:0.1%"/><td style="width:1.0%"/><td style="width:16.909%"/><td style="width:0.1%"/></tr><tr><td colspan="3" style="padding:2px 1pt;text-align:left;vertical-align:top"><span style="color:#000000;font-family:'Times New Roman',sans-serif;font-size:8pt;font-weight:700;line-height:100%">Year Ended <br/>December 31,</span></td><td colspan="3" style="padding:2px 1pt;text-align:center;vertical-align:bottom"><span style="color:#000000;font-family:'Times New Roman',sans-serif;font-size:8pt;font-weight:700;line-height:100%">2020</span></td><td colspan="3" style="padding:0 1pt"/><td colspan="3" style="padding:2px 1pt;text-align:center;vertical-align:bottom"><span style="color:#000000;font-family:'Times New Roman',sans-serif;font-size:8pt;font-weight:700;line-height:100%">2019</span></td><td colspan="3" style="padding:0 1pt"/><td colspan="3" style="padding:2px 1pt;text-align:center;vertical-align:bottom"><span style="color:#000000;font-family:'Times New Roman',sans-serif;font-size:8pt;font-weight:700;line-height:100%">2018</span></td></tr><tr><td colspan="3" style="background-color:#cceeff;border-top:1pt solid #000000;padding:2px 1pt;text-align:left;vertical-align:bottom"><div style="padding-left:4.5pt;text-indent:-4.5pt"><span style="color:#000000;font-family:'Times New Roman',sans-serif;font-size:8pt;font-weight:700;line-height:100%">Beginning gross loss and loss expense reserves</span></div></td><td style="background-color:#cceeff;border-top:1pt solid #000000;padding:2px 0 2px 1pt;text-align:left;vertical-align:bottom"><span style="color:#211aff;font-family:'Times New Roman',sans-serif;font-size:8pt;font-weight:700;line-height:100%">$</span></td><td style="background-color:#cceeff;border-top:1pt solid #000000;padding:2px 0;text-align:right;vertical-align:bottom"><span style="color:#211aff;font-family:'Times New Roman',sans-serif;font-size:8pt;font-weight:700;line-height:100%">(482)</span></td><td style="background-color:#cceeff;border-top:1pt solid #000000;padding:2px 1pt 2px 0;text-align:right;vertical-align:bottom"/><td colspan="3" style="background-color:#cceeff;border-top:1pt solid #000000;padding:0 1pt"/><td style="background-color:#cceeff;border-top:1pt solid #000000;padding:2px 0 2px 1pt;text-align:left;vertical-align:bottom"><span style="color:#000000;font-family:'Times New Roman',sans-serif;font-size:8pt;font-weight:400;line-height:100%">$</span></td><td style="background-color:#cceeff;border-top:1pt solid #000000;padding:2px 0;text-align:right;vertical-align:bottom"><span style="color:#000000;font-family:'Times New Roman',sans-serif;font-size:8pt;font-weight:400;line-height:100%">(107)</span></td><td style="background-color:#cceeff;border-top:1pt solid #000000;padding:2px 1pt 2px 0;text-align:right;vertical-align:bottom"/><td colspan="3" style="background-color:#cceeff;border-top:1pt solid #000000;padding:0 1pt"/><td style="background-color:#cceeff;border-top:1pt solid #000000;padding:2px 0 2px 1pt;text-align:left;vertical-align:bottom"><span style="color:#000000;font-family:'Times New Roman',sans-serif;font-size:8pt;font-weight:400;line-height:100%">$</span></td><td style="background-color:#cceeff;border-top:1pt solid #000000;padding:2px 0;text-align:right;vertical-align:bottom"><span style="color:#000000;font-family:'Times New Roman',sans-serif;font-size:8pt;font-weight:400;line-height:100%">4,114 </span></td><td style="background-color:#cceeff;border-top:1pt solid #000000;padding:2px 1pt 2px 0;text-align:right;vertical-align:bottom"/></tr><tr><td colspan="3" style="background-color:#ffffff;padding:2px 1pt;text-align:left;vertical-align:bottom"><div style="padding-left:4.5pt;text-indent:-4.5pt"><span style="color:#000000;font-family:'Times New Roman',sans-serif;font-size:8pt;font-weight:400;line-height:100%">Reinsurance recoverable</span></div></td><td colspan="2" style="background-color:#ffffff;padding:2px 0 2px 1pt;text-align:right;vertical-align:bottom"><span style="color:#211aff;font-family:'Times New Roman',sans-serif;font-size:8pt;font-weight:700;line-height:100%">26</span><span style="color:#211aff;font-family:'Times New Roman',sans-serif;font-size:8pt;font-weight:400;line-height:100%"> </span></td><td style="background-color:#ffffff;padding:2px 1pt 2px 0;text-align:right;vertical-align:bottom"/><td colspan="3" style="background-color:#ffffff;padding:0 1pt"/><td colspan="2" style="background-color:#ffffff;padding:2px 0 2px 1pt;text-align:right;vertical-align:bottom"><span style="color:#000000;font-family:'Times New Roman',sans-serif;font-size:8pt;font-weight:400;line-height:100%">23 </span></td><td style="background-color:#ffffff;padding:2px 1pt 2px 0;text-align:right;vertical-align:bottom"/><td colspan="3" style="background-color:#ffffff;padding:0 1pt"/><td colspan="2" style="background-color:#ffffff;padding:2px 0 2px 1pt;text-align:right;vertical-align:bottom"><span style="color:#000000;font-family:'Times New Roman',sans-serif;font-size:8pt;font-weight:400;line-height:100%">41 </span></td><td style="background-color:#ffffff;padding:2px 1pt 2px 0;text-align:right;vertical-align:bottom"/></tr><tr><td colspan="3" style="background-color:#cceeff;border-top:1pt solid #000000;padding:2px 1pt;text-align:left;vertical-align:bottom"><div style="padding-left:4.5pt;text-indent:-4.5pt"><span style="color:#000000;font-family:'Times New Roman',sans-serif;font-size:8pt;font-weight:400;line-height:100%">Beginning balance of net loss and loss expense reserves</span></div></td><td colspan="2" style="background-color:#cceeff;border-top:1pt solid #000000;padding:2px 0 2px 1pt;text-align:right;vertical-align:bottom"><span style="color:#211aff;font-family:'Times New Roman',sans-serif;font-size:8pt;font-weight:700;line-height:100%">(508)</span></td><td style="background-color:#cceeff;border-top:1pt solid #000000;padding:2px 1pt 2px 0;text-align:right;vertical-align:bottom"/><td colspan="3" style="background-color:#cceeff;border-top:1pt solid #000000;padding:0 1pt"/><td colspan="2" style="background-color:#cceeff;border-top:1pt solid #000000;padding:2px 0 2px 1pt;text-align:right;vertical-align:bottom"><span style="color:#000000;font-family:'Times New Roman',sans-serif;font-size:8pt;font-weight:400;line-height:100%">(130)</span></td><td style="background-color:#cceeff;border-top:1pt solid #000000;padding:2px 1pt 2px 0;text-align:right;vertical-align:bottom"/><td colspan="3" style="background-color:#cceeff;border-top:1pt solid #000000;padding:0 1pt"/><td colspan="2" style="background-color:#cceeff;border-top:1pt solid #000000;padding:2px 0 2px 1pt;text-align:right;vertical-align:bottom"><span style="color:#000000;font-family:'Times New Roman',sans-serif;font-size:8pt;font-weight:400;line-height:100%">4,073 </span></td><td style="background-color:#cceeff;border-top:1pt solid #000000;padding:2px 1pt 2px 0;text-align:right;vertical-align:bottom"/></tr><tr><td colspan="3" style="background-color:#ffffff;padding:2px 1pt;text-align:left;vertical-align:bottom"><div style="padding-left:4.5pt;text-indent:-4.5pt"><span style="color:#000000;font-family:'Times New Roman',sans-serif;font-size:8pt;font-weight:700;line-height:100%">Losses and loss expenses (benefit) incurred:</span></div></td><td colspan="3" style="background-color:#ffffff;padding:0 1pt"/><td colspan="3" style="background-color:#ffffff;padding:0 1pt"/><td colspan="3" style="background-color:#ffffff;padding:0 1pt"/><td colspan="3" style="background-color:#ffffff;padding:0 1pt"/><td colspan="3" style="background-color:#ffffff;padding:0 1pt"/></tr><tr><td colspan="3" style="background-color:#cceeff;padding:2px 1pt;text-align:left;vertical-align:bottom"><div style="padding-left:11.25pt;text-indent:-4.5pt"><span style="color:#000000;font-family:'Times New Roman',sans-serif;font-size:8pt;font-weight:400;line-height:100%">Current year</span></div></td><td colspan="2" style="background-color:#cceeff;padding:2px 0 2px 1pt;text-align:right;vertical-align:bottom"><span style="color:#211aff;font-family:'Times New Roman',sans-serif;font-size:8pt;font-weight:700;line-height:100%">15</span><span style="color:#211aff;font-family:'Times New Roman',sans-serif;font-size:8pt;font-weight:400;line-height:100%"> </span></td><td style="background-color:#cceeff;padding:2px 1pt 2px 0;text-align:right;vertical-align:bottom"/><td colspan="3" style="background-color:#cceeff;padding:0 1pt"/><td colspan="2" style="background-color:#cceeff;padding:2px 0 2px 1pt;text-align:right;vertical-align:bottom"><span style="color:#000000;font-family:'Times New Roman',sans-serif;font-size:8pt;font-weight:400;line-height:100%">1 </span></td><td style="background-color:#cceeff;padding:2px 1pt 2px 0;text-align:right;vertical-align:bottom"/><td colspan="3" style="background-color:#cceeff;padding:0 1pt"/><td colspan="2" style="background-color:#cceeff;padding:2px 0 2px 1pt;text-align:right;vertical-align:bottom"><span style="color:#000000;font-family:'Times New Roman',sans-serif;font-size:8pt;font-weight:400;line-height:100%">5 </span></td><td style="background-color:#cceeff;padding:2px 1pt 2px 0;text-align:right;vertical-align:bottom"/></tr><tr><td colspan="3" style="background-color:#ffffff;padding:2px 1pt;text-align:left;vertical-align:bottom"><div style="padding-left:11.25pt;text-indent:-4.5pt"><span style="color:#000000;font-family:'Times New Roman',sans-serif;font-size:8pt;font-weight:400;line-height:100%">Prior years </span><span style="color:#000000;font-family:'Times New Roman',sans-serif;font-size:5.2pt;font-weight:400;line-height:100%;position:relative;top:-2.8pt;vertical-align:baseline">(1)</span></div></td><td colspan="2" style="background-color:#ffffff;padding:2px 0 2px 1pt;text-align:right;vertical-align:bottom"><span style="color:#211aff;font-family:'Times New Roman',sans-serif;font-size:8pt;font-weight:700;line-height:100%">210</span><span style="color:#211aff;font-family:'Times New Roman',sans-serif;font-size:8pt;font-weight:400;line-height:100%"> </span></td><td style="background-color:#ffffff;padding:2px 1pt 2px 0;text-align:right;vertical-align:bottom"/><td colspan="3" style="background-color:#ffffff;padding:0 1pt"/><td colspan="2" style="background-color:#ffffff;padding:2px 0 2px 1pt;text-align:right;vertical-align:bottom"><span style="color:#000000;font-family:'Times New Roman',sans-serif;font-size:8pt;font-weight:400;line-height:100%">12 </span></td><td style="background-color:#ffffff;padding:2px 1pt 2px 0;text-align:right;vertical-align:bottom"/><td colspan="3" style="background-color:#ffffff;padding:0 1pt"/><td colspan="2" style="background-color:#ffffff;padding:2px 0 2px 1pt;text-align:right;vertical-align:bottom"><span style="color:#000000;font-family:'Times New Roman',sans-serif;font-size:8pt;font-weight:400;line-height:100%">(228)</span></td><td style="background-color:#ffffff;padding:2px 1pt 2px 0;text-align:right;vertical-align:bottom"/></tr><tr><td colspan="3" style="background-color:#cceeff;border-top:1pt solid #000000;padding:2px 1pt;text-align:left;vertical-align:bottom"><div style="padding-left:4.5pt;text-indent:-4.5pt"><span style="color:#000000;font-family:'Times New Roman',sans-serif;font-size:8pt;font-weight:400;line-height:100%">Total </span><span style="color:#000000;font-family:'Times New Roman',sans-serif;font-size:5.2pt;font-weight:400;line-height:100%;position:relative;top:-2.8pt;vertical-align:baseline">(2)(3)</span></div></td><td colspan="2" style="background-color:#cceeff;border-top:1pt solid #000000;padding:2px 0 2px 1pt;text-align:right;vertical-align:bottom"><span style="color:#211aff;font-family:'Times New Roman',sans-serif;font-size:8pt;font-weight:700;line-height:100%">225</span><span style="color:#211aff;font-family:'Times New Roman',sans-serif;font-size:8pt;font-weight:400;line-height:100%"> </span></td><td style="background-color:#cceeff;border-top:1pt solid #000000;padding:2px 1pt 2px 0;text-align:right;vertical-align:bottom"/><td colspan="3" style="background-color:#cceeff;border-top:1pt solid #000000;padding:0 1pt"/><td colspan="2" style="background-color:#cceeff;border-top:1pt solid #000000;padding:2px 0 2px 1pt;text-align:right;vertical-align:bottom"><span style="color:#000000;font-family:'Times New Roman',sans-serif;font-size:8pt;font-weight:400;line-height:100%">13 </span></td><td style="background-color:#cceeff;border-top:1pt solid #000000;padding:2px 1pt 2px 0;text-align:right;vertical-align:bottom"/><td colspan="3" style="background-color:#cceeff;border-top:1pt solid #000000;padding:0 1pt"/><td colspan="2" style="background-color:#cceeff;border-top:1pt solid #000000;padding:2px 0 2px 1pt;text-align:right;vertical-align:bottom"><span style="color:#000000;font-family:'Times New Roman',sans-serif;font-size:8pt;font-weight:400;line-height:100%">(224)</span></td><td style="background-color:#cceeff;border-top:1pt solid #000000;padding:2px 1pt 2px 0;text-align:right;vertical-align:bottom"/></tr><tr><td colspan="3" style="background-color:#ffffff;border-top:1pt solid #000000;padding:2px 1pt;text-align:left;vertical-align:bottom"><div style="padding-left:4.5pt;text-indent:-4.5pt"><span style="color:#000000;font-family:'Times New Roman',sans-serif;font-size:8pt;font-weight:700;line-height:100%">Loss and loss expenses (recovered) paid:</span></div></td><td colspan="3" style="background-color:#ffffff;border-top:1pt solid #000000;padding:0 1pt"/><td colspan="3" style="background-color:#ffffff;border-top:1pt solid #000000;padding:0 1pt"/><td colspan="3" style="background-color:#ffffff;border-top:1pt solid #000000;padding:0 1pt"/><td colspan="3" style="background-color:#ffffff;border-top:1pt solid #000000;padding:0 1pt"/><td colspan="3" style="background-color:#ffffff;border-top:1pt solid #000000;padding:0 1pt"/></tr><tr><td colspan="3" style="background-color:#cceeff;padding:2px 1pt;text-align:left;vertical-align:bottom"><div style="padding-left:11.25pt;text-indent:-4.5pt"><span style="color:#000000;font-family:'Times New Roman',sans-serif;font-size:8pt;font-weight:400;line-height:100%">Current year</span></div></td><td colspan="2" style="background-color:#cceeff;padding:2px 0 2px 1pt;text-align:right;vertical-align:bottom"><span style="color:#211aff;font-family:'Times New Roman',sans-serif;font-size:8pt;font-weight:700;line-height:100%">1</span><span style="color:#211aff;font-family:'Times New Roman',sans-serif;font-size:8pt;font-weight:400;line-height:100%"> </span></td><td style="background-color:#cceeff;padding:2px 1pt 2px 0;text-align:right;vertical-align:bottom"/><td colspan="3" style="background-color:#cceeff;padding:0 1pt"/><td colspan="2" style="background-color:#cceeff;padding:2px 0 2px 1pt;text-align:right;vertical-align:bottom"><span style="color:#000000;font-family:'Times New Roman',sans-serif;font-size:8pt;font-weight:400;line-height:100%">— </span></td><td style="background-color:#cceeff;padding:2px 1pt 2px 0;text-align:right;vertical-align:bottom"/><td colspan="3" style="background-color:#cceeff;padding:0 1pt"/><td colspan="2" style="background-color:#cceeff;padding:2px 0 2px 1pt;text-align:right;vertical-align:bottom"><span style="color:#000000;font-family:'Times New Roman',sans-serif;font-size:8pt;font-weight:400;line-height:100%">— </span></td><td style="background-color:#cceeff;padding:2px 1pt 2px 0;text-align:right;vertical-align:bottom"/></tr><tr><td colspan="3" style="background-color:#ffffff;padding:2px 1pt;text-align:left;vertical-align:bottom"><div style="padding-left:11.25pt;text-indent:-4.5pt"><span style="color:#000000;font-family:'Times New Roman',sans-serif;font-size:8pt;font-weight:400;line-height:100%">Prior years </span><span style="color:#000000;font-family:'Times New Roman',sans-serif;font-size:5.2pt;font-weight:400;line-height:100%;position:relative;top:-2.8pt;vertical-align:baseline">(1)</span></div></td><td colspan="2" style="background-color:#ffffff;padding:2px 0 2px 1pt;text-align:right;vertical-align:bottom"><span style="color:#211aff;font-family:'Times New Roman',sans-serif;font-size:8pt;font-weight:700;line-height:100%">148</span><span style="color:#211aff;font-family:'Times New Roman',sans-serif;font-size:8pt;font-weight:400;line-height:100%"> </span></td><td style="background-color:#ffffff;padding:2px 1pt 2px 0;text-align:right;vertical-align:bottom"/><td colspan="3" style="background-color:#ffffff;padding:0 1pt"/><td colspan="2" style="background-color:#ffffff;padding:2px 0 2px 1pt;text-align:right;vertical-align:bottom"><span style="color:#000000;font-family:'Times New Roman',sans-serif;font-size:8pt;font-weight:400;line-height:100%">318 </span></td><td style="background-color:#ffffff;padding:2px 1pt 2px 0;text-align:right;vertical-align:bottom"/><td colspan="3" style="background-color:#ffffff;padding:0 1pt"/><td colspan="2" style="background-color:#ffffff;padding:2px 0 2px 1pt;text-align:right;vertical-align:bottom"><span style="color:#000000;font-family:'Times New Roman',sans-serif;font-size:8pt;font-weight:400;line-height:100%">3,963 </span></td><td style="background-color:#ffffff;padding:2px 1pt 2px 0;text-align:right;vertical-align:bottom"/></tr><tr><td colspan="3" style="background-color:#cceeff;border-top:1pt solid #000000;padding:2px 1pt;text-align:left;vertical-align:bottom"><div style="padding-left:4.5pt;text-indent:-4.5pt"><span style="color:#000000;font-family:'Times New Roman',sans-serif;font-size:8pt;font-weight:400;line-height:100%">Total</span></div></td><td colspan="2" style="background-color:#cceeff;border-top:1pt solid #000000;padding:2px 0 2px 1pt;text-align:right;vertical-align:bottom"><span style="color:#211aff;font-family:'Times New Roman',sans-serif;font-size:8pt;font-weight:700;line-height:100%">149</span><span style="color:#211aff;font-family:'Times New Roman',sans-serif;font-size:8pt;font-weight:400;line-height:100%"> </span></td><td style="background-color:#cceeff;border-top:1pt solid #000000;padding:2px 1pt 2px 0;text-align:right;vertical-align:bottom"/><td colspan="3" style="background-color:#cceeff;border-top:1pt solid #000000;padding:0 1pt"/><td colspan="2" style="background-color:#cceeff;border-top:1pt solid #000000;padding:2px 0 2px 1pt;text-align:right;vertical-align:bottom"><span style="color:#000000;font-family:'Times New Roman',sans-serif;font-size:8pt;font-weight:400;line-height:100%">318 </span></td><td style="background-color:#cceeff;border-top:1pt solid #000000;padding:2px 1pt 2px 0;text-align:right;vertical-align:bottom"/><td colspan="3" style="background-color:#cceeff;border-top:1pt solid #000000;padding:0 1pt"/><td colspan="2" style="background-color:#cceeff;border-top:1pt solid #000000;padding:2px 0 2px 1pt;text-align:right;vertical-align:bottom"><span style="color:#000000;font-family:'Times New Roman',sans-serif;font-size:8pt;font-weight:400;line-height:100%">3,964 </span></td><td style="background-color:#cceeff;border-top:1pt solid #000000;padding:2px 1pt 2px 0;text-align:right;vertical-align:bottom"/></tr><tr><td colspan="3" style="background-color:#ffffff;border-top:1pt solid #000000;padding:2px 1pt;text-align:left;vertical-align:bottom"><div style="padding-left:4.5pt;text-indent:-4.5pt"><span style="color:#000000;font-family:'Times New Roman',sans-serif;font-size:8pt;font-weight:400;line-height:100%">Foreign exchange effect</span></div></td><td colspan="2" style="background-color:#ffffff;border-top:1pt solid #000000;padding:2px 0 2px 1pt;text-align:right;vertical-align:bottom"><span style="color:#211aff;font-family:'Times New Roman',sans-serif;font-size:8pt;font-weight:700;line-height:100%">2</span><span style="color:#211aff;font-family:'Times New Roman',sans-serif;font-size:8pt;font-weight:400;line-height:100%"> </span></td><td style="background-color:#ffffff;border-top:1pt solid #000000;padding:2px 1pt 2px 0;text-align:right;vertical-align:bottom"/><td colspan="3" style="background-color:#ffffff;border-top:1pt solid #000000;padding:0 1pt"/><td colspan="2" style="background-color:#ffffff;border-top:1pt solid #000000;padding:2px 0 2px 1pt;text-align:right;vertical-align:bottom"><span style="color:#000000;font-family:'Times New Roman',sans-serif;font-size:8pt;font-weight:400;line-height:100%">(1)</span></td><td style="background-color:#ffffff;border-top:1pt solid #000000;padding:2px 1pt 2px 0;text-align:right;vertical-align:bottom"/><td colspan="3" style="background-color:#ffffff;border-top:1pt solid #000000;padding:0 1pt"/><td colspan="2" style="background-color:#ffffff;border-top:1pt solid #000000;padding:2px 0 2px 1pt;text-align:right;vertical-align:bottom"><span style="color:#000000;font-family:'Times New Roman',sans-serif;font-size:8pt;font-weight:400;line-height:100%">(15)</span></td><td style="background-color:#ffffff;border-top:1pt solid #000000;padding:2px 1pt 2px 0;text-align:right;vertical-align:bottom"/></tr><tr><td colspan="3" style="background-color:#cceeff;border-top:1pt solid #000000;padding:2px 1pt;text-align:left;vertical-align:bottom"><div style="padding-left:4.5pt;text-indent:-4.5pt"><span style="color:#000000;font-family:'Times New Roman',sans-serif;font-size:8pt;font-weight:400;line-height:100%">Ending net loss and loss expense reserves</span></div></td><td colspan="2" style="background-color:#cceeff;border-top:1pt solid #000000;padding:2px 0 2px 1pt;text-align:right;vertical-align:bottom"><span style="color:#211aff;font-family:'Times New Roman',sans-serif;font-size:8pt;font-weight:700;line-height:100%">(430)</span></td><td style="background-color:#cceeff;border-top:1pt solid #000000;padding:2px 1pt 2px 0;text-align:right;vertical-align:bottom"/><td colspan="3" style="background-color:#cceeff;border-top:1pt solid #000000;padding:0 1pt"/><td colspan="2" style="background-color:#cceeff;border-top:1pt solid #000000;padding:2px 0 2px 1pt;text-align:right;vertical-align:bottom"><span style="color:#000000;font-family:'Times New Roman',sans-serif;font-size:8pt;font-weight:400;line-height:100%">(436)</span></td><td style="background-color:#cceeff;border-top:1pt solid #000000;padding:2px 1pt 2px 0;text-align:right;vertical-align:bottom"/><td colspan="3" style="background-color:#cceeff;border-top:1pt solid #000000;padding:0 1pt"/><td colspan="2" style="background-color:#cceeff;border-top:1pt solid #000000;padding:2px 0 2px 1pt;text-align:right;vertical-align:bottom"><span style="color:#000000;font-family:'Times New Roman',sans-serif;font-size:8pt;font-weight:400;line-height:100%">(130)</span></td><td style="background-color:#cceeff;border-top:1pt solid #000000;padding:2px 1pt 2px 0;text-align:right;vertical-align:bottom"/></tr><tr><td colspan="3" style="background-color:#ffffff;padding:2px 1pt;text-align:left;vertical-align:bottom"><div style="padding-left:4.5pt;text-indent:-4.5pt"><span style="color:#000000;font-family:'Times New Roman',sans-serif;font-size:8pt;font-weight:400;line-height:100%">Impact of VIE consolidation</span></div></td><td colspan="2" style="background-color:#ffffff;padding:2px 0 2px 1pt;text-align:right;vertical-align:bottom"><span style="color:#211aff;font-family:'Times New Roman',sans-serif;font-size:8pt;font-weight:700;line-height:100%">—</span><span style="color:#211aff;font-family:'Times New Roman',sans-serif;font-size:8pt;font-weight:400;line-height:100%"> </span></td><td style="background-color:#ffffff;padding:2px 1pt 2px 0;text-align:right;vertical-align:bottom"/><td colspan="3" style="background-color:#ffffff;padding:0 1pt"/><td colspan="2" style="background-color:#ffffff;padding:2px 0 2px 1pt;text-align:right;vertical-align:bottom"><span style="color:#000000;font-family:'Times New Roman',sans-serif;font-size:8pt;font-weight:400;line-height:100%">(72)</span></td><td style="background-color:#ffffff;padding:2px 1pt 2px 0;text-align:right;vertical-align:bottom"/><td colspan="3" style="background-color:#ffffff;padding:0 1pt"/><td colspan="2" style="background-color:#ffffff;padding:2px 0 2px 1pt;text-align:right;vertical-align:bottom"><span style="color:#000000;font-family:'Times New Roman',sans-serif;font-size:8pt;font-weight:400;line-height:100%">— </span></td><td style="background-color:#ffffff;padding:2px 1pt 2px 0;text-align:right;vertical-align:bottom"/></tr><tr><td colspan="3" style="background-color:#cceeff;padding:2px 1pt;text-align:left;vertical-align:bottom"><div style="padding-left:4.5pt;text-indent:-4.5pt"><span style="color:#000000;font-family:'Times New Roman',sans-serif;font-size:8pt;font-weight:400;line-height:100%">Reinsurance recoverable </span><span style="color:#000000;font-family:'Times New Roman',sans-serif;font-size:5.2pt;font-weight:400;line-height:100%;position:relative;top:-2.8pt;vertical-align:baseline">(4)</span></div></td><td colspan="2" style="background-color:#cceeff;padding:2px 0 2px 1pt;text-align:right;vertical-align:bottom"><span style="color:#211aff;font-family:'Times New Roman',sans-serif;font-size:8pt;font-weight:700;line-height:100%">33</span><span style="color:#211aff;font-family:'Times New Roman',sans-serif;font-size:8pt;font-weight:400;line-height:100%"> </span></td><td style="background-color:#cceeff;padding:2px 1pt 2px 0;text-align:right;vertical-align:bottom"/><td colspan="3" style="background-color:#cceeff;padding:0 1pt"/><td colspan="2" style="background-color:#cceeff;padding:2px 0 2px 1pt;text-align:right;vertical-align:bottom"><span style="color:#000000;font-family:'Times New Roman',sans-serif;font-size:8pt;font-weight:400;line-height:100%">26 </span></td><td style="background-color:#cceeff;padding:2px 1pt 2px 0;text-align:right;vertical-align:bottom"/><td colspan="3" style="background-color:#cceeff;padding:0 1pt"/><td colspan="2" style="background-color:#cceeff;padding:2px 0 2px 1pt;text-align:right;vertical-align:bottom"><span style="color:#000000;font-family:'Times New Roman',sans-serif;font-size:8pt;font-weight:400;line-height:100%">23 </span></td><td style="background-color:#cceeff;padding:2px 1pt 2px 0;text-align:right;vertical-align:bottom"/></tr><tr><td colspan="3" style="background-color:#ffffff;border-bottom:3pt double #000000;border-top:1pt solid #000000;padding:2px 1pt;text-align:left;vertical-align:bottom"><div style="padding-left:4.5pt;text-indent:-4.5pt"><span style="color:#000000;font-family:'Times New Roman',sans-serif;font-size:8pt;font-weight:700;line-height:100%">Ending gross loss and loss expense reserves</span></div></td><td colspan="2" style="background-color:#ffffff;border-bottom:3pt double #000000;border-top:1pt solid #000000;padding:2px 0 2px 1pt;text-align:right;vertical-align:bottom"><span style="color:#211aff;font-family:'Times New Roman',sans-serif;font-size:8pt;font-weight:700;line-height:100%">(397)</span></td><td style="background-color:#ffffff;border-bottom:3pt double #000000;border-top:1pt solid #000000;padding:2px 1pt 2px 0;text-align:right;vertical-align:bottom"/><td colspan="3" style="background-color:#ffffff;border-bottom:3pt double #000000;border-top:1pt solid #000000;padding:0 1pt"/><td colspan="2" style="background-color:#ffffff;border-bottom:3pt double #000000;border-top:1pt solid #000000;padding:2px 0 2px 1pt;text-align:right;vertical-align:bottom"><span style="color:#000000;font-family:'Times New Roman',sans-serif;font-size:8pt;font-weight:700;line-height:100%">(482)</span></td><td style="background-color:#ffffff;border-bottom:3pt double #000000;border-top:1pt solid #000000;padding:2px 1pt 2px 0;text-align:right;vertical-align:bottom"/><td colspan="3" style="background-color:#ffffff;border-bottom:3pt double #000000;border-top:1pt solid #000000;padding:0 1pt"/><td colspan="2" style="background-color:#ffffff;border-bottom:3pt double #000000;border-top:1pt solid #000000;padding:2px 0 2px 1pt;text-align:right;vertical-align:bottom"><span style="color:#000000;font-family:'Times New Roman',sans-serif;font-size:8pt;font-weight:700;line-height:100%">(107)</span></td><td style="background-color:#ffffff;border-bottom:3pt double #000000;border-top:1pt solid #000000;padding:2px 1pt 2px 0;text-align:right;vertical-align:bottom"/></tr></table></div><div style="margin-top:9pt;padding-left:18pt;text-align:justify;text-indent:-18pt"><span style="color:#000000;font-family:'Times New Roman',sans-serif;font-size:8pt;font-weight:400;line-height:120%">(1)</span><span style="color:#000000;font-family:'Times New Roman',sans-serif;font-size:8pt;font-weight:400;line-height:120%;padding-left:8.68pt">2018 loss and loss expenses (recovered) paid includes the settlement of Deferred Amounts and Interest Accrued on Deferred Amounts in the amount of $3,000 and $857, respectively in connection with the Rehabilitation Exit Transactions through a combination of cash, surplus notes and secured notes. 2018 loss and loss expenses incurred includes a $288 loss and loss expense benefit on these settled Deferred Amounts.</span></div><div style="padding-left:18pt;text-align:justify;text-indent:-18pt"><span style="color:#000000;font-family:'Times New Roman',sans-serif;font-size:8pt;font-weight:400;line-height:120%">(2)</span><span style="color:#000000;font-family:'Times New Roman',sans-serif;font-size:8pt;font-weight:400;line-height:120%;padding-left:8.68pt">Total losses and loss expenses (benefit) includes $(11), $(7) and $(2) for the years ended December 31, 2020, 2019 and 2018, respectively, related to ceded reinsurance.</span></div><div style="padding-left:18pt;text-align:justify;text-indent:-18pt"><span style="color:#000000;font-family:'Times New Roman',sans-serif;font-size:8pt;font-weight:400;line-height:120%">(3)</span><span style="color:#000000;font-family:'Times New Roman',sans-serif;font-size:8pt;font-weight:400;line-height:120%;padding-left:8.68pt">Ambac records the impact of estimated recoveries related to securitized loans in RMBS transactions that breached certain representations and warranties within losses and loss expenses (benefit). The losses and loss expense (benefit) incurred associated with changes in estimated representation and warranty recoveries for the year ended December 31, 2020, 2019 and 2018 was $(23), $42 and $62, respectively.</span></div><div style="margin-bottom:6pt;padding-left:18pt;text-align:justify;text-indent:-18pt"><span style="color:#000000;font-family:'Times New Roman',sans-serif;font-size:8pt;font-weight:400;line-height:120%">(4)</span><span style="color:#000000;font-family:'Times New Roman',sans-serif;font-size:8pt;font-weight:400;line-height:120%;padding-left:8.68pt">Represents reinsurance recoverable on future loss and loss expenses. Additionally, the Balance Sheet line "Reinsurance recoverable on paid and unpaid losses (net of allowance for credit losses of $0 at December 31, 2020)" includes reinsurance recoverables (payables) of $1, $0 and $1 as of December 31, 2020, 2019 and 2018, respectively, related to previously presented loss and loss expenses and subrogation.</span></div>

CY2019Q4

us-gaap

Liability For Claims And Claims Adjustment Expense

LiabilityForClaimsAndClaimsAdjustmentExpense

-482000000

USD

CY2018Q4

us-gaap

Liability For Claims And Claims Adjustment Expense

LiabilityForClaimsAndClaimsAdjustmentExpense

-107000000

USD

CY2017Q4

us-gaap

Liability For Claims And Claims Adjustment Expense

LiabilityForClaimsAndClaimsAdjustmentExpense

4114000000

USD

CY2019Q4

ambc

Loss Reserves Ceded To Reinsurers

LossReservesCededToReinsurers

26000000

USD

CY2018Q4

ambc

Loss Reserves Ceded To Reinsurers

LossReservesCededToReinsurers

23000000

USD

CY2017Q4

ambc

Loss Reserves Ceded To Reinsurers

LossReservesCededToReinsurers

41000000

USD

CY2019Q4

ambc

Liability For Unpaid Claims And Claims Adjustment Expense Net Netof Impactof Vie Consolidation

LiabilityForUnpaidClaimsAndClaimsAdjustmentExpenseNetNetofImpactofVIEConsolidation

-508000000

USD

CY2018Q4

us-gaap

Liability For Unpaid Claims And Claims Adjustment Expense Net

LiabilityForUnpaidClaimsAndClaimsAdjustmentExpenseNet

-130000000

USD

CY2017Q4

us-gaap

Liability For Unpaid Claims And Claims Adjustment Expense Net

LiabilityForUnpaidClaimsAndClaimsAdjustmentExpenseNet

4073000000

USD

CY2020

us-gaap

Supplemental Information For Property Casualty Insurance Underwriters Current Year Claims And Claims Adjustment Expense

SupplementalInformationForPropertyCasualtyInsuranceUnderwritersCurrentYearClaimsAndClaimsAdjustmentExpense

15000000

USD

CY2019

us-gaap

Supplemental Information For Property Casualty Insurance Underwriters Current Year Claims And Claims Adjustment Expense

SupplementalInformationForPropertyCasualtyInsuranceUnderwritersCurrentYearClaimsAndClaimsAdjustmentExpense

1000000

USD

CY2018

us-gaap

Supplemental Information For Property Casualty Insurance Underwriters Current Year Claims And Claims Adjustment Expense

SupplementalInformationForPropertyCasualtyInsuranceUnderwritersCurrentYearClaimsAndClaimsAdjustmentExpense

5000000

USD

CY2020

us-gaap

Supplemental Information For Property Casualty Insurance Underwriters Prior Year Claims And Claims Adjustment Expense

SupplementalInformationForPropertyCasualtyInsuranceUnderwritersPriorYearClaimsAndClaimsAdjustmentExpense

210000000

USD

CY2019

us-gaap

Supplemental Information For Property Casualty Insurance Underwriters Prior Year Claims And Claims Adjustment Expense

SupplementalInformationForPropertyCasualtyInsuranceUnderwritersPriorYearClaimsAndClaimsAdjustmentExpense

12000000

USD

CY2018

us-gaap

Supplemental Information For Property Casualty Insurance Underwriters Prior Year Claims And Claims Adjustment Expense

SupplementalInformationForPropertyCasualtyInsuranceUnderwritersPriorYearClaimsAndClaimsAdjustmentExpense

-228000000

USD

CY2020

us-gaap

Liability For Unpaid Claims And Claims Adjustment Expense Incurred Claims1

LiabilityForUnpaidClaimsAndClaimsAdjustmentExpenseIncurredClaims1

225000000

USD

CY2019

us-gaap

Liability For Unpaid Claims And Claims Adjustment Expense Incurred Claims1

LiabilityForUnpaidClaimsAndClaimsAdjustmentExpenseIncurredClaims1

13000000

USD

CY2018

us-gaap

Liability For Unpaid Claims And Claims Adjustment Expense Incurred Claims1

LiabilityForUnpaidClaimsAndClaimsAdjustmentExpenseIncurredClaims1

-224000000

USD

CY2020

us-gaap

Liability For Unpaid Claims And Claims Adjustment Expense Claims Paid Current Year1

LiabilityForUnpaidClaimsAndClaimsAdjustmentExpenseClaimsPaidCurrentYear1

1000000

USD

CY2019

us-gaap

Liability For Unpaid Claims And Claims Adjustment Expense Claims Paid Current Year1

LiabilityForUnpaidClaimsAndClaimsAdjustmentExpenseClaimsPaidCurrentYear1

0

USD

CY2018

us-gaap

Liability For Unpaid Claims And Claims Adjustment Expense Claims Paid Current Year1

LiabilityForUnpaidClaimsAndClaimsAdjustmentExpenseClaimsPaidCurrentYear1

0

USD

CY2020

us-gaap

Liability For Unpaid Claims And Claims Adjustment Expense Claims Paid Prior Years1

LiabilityForUnpaidClaimsAndClaimsAdjustmentExpenseClaimsPaidPriorYears1

148000000

USD

CY2019

us-gaap

Liability For Unpaid Claims And Claims Adjustment Expense Claims Paid Prior Years1

LiabilityForUnpaidClaimsAndClaimsAdjustmentExpenseClaimsPaidPriorYears1

318000000

USD

CY2018

us-gaap

Liability For Unpaid Claims And Claims Adjustment Expense Claims Paid Prior Years1

LiabilityForUnpaidClaimsAndClaimsAdjustmentExpenseClaimsPaidPriorYears1

3963000000

USD

CY2020

us-gaap

Payments For Losses And Loss Adjustment Expense

PaymentsForLossesAndLossAdjustmentExpense

149000000

USD

CY2019

us-gaap

Payments For Losses And Loss Adjustment Expense

PaymentsForLossesAndLossAdjustmentExpense

318000000

USD

CY2018

us-gaap

Payments For Losses And Loss Adjustment Expense

PaymentsForLossesAndLossAdjustmentExpense

3964000000

USD

CY2020

us-gaap

Liability For Unpaid Claims And Claims Adjustment Expense Foreign Currency Translation Gain Loss

LiabilityForUnpaidClaimsAndClaimsAdjustmentExpenseForeignCurrencyTranslationGainLoss

2000000

USD

CY2019

us-gaap

Liability For Unpaid Claims And Claims Adjustment Expense Foreign Currency Translation Gain Loss

LiabilityForUnpaidClaimsAndClaimsAdjustmentExpenseForeignCurrencyTranslationGainLoss

-1000000

USD

CY2018

us-gaap

Liability For Unpaid Claims And Claims Adjustment Expense Foreign Currency Translation Gain Loss

LiabilityForUnpaidClaimsAndClaimsAdjustmentExpenseForeignCurrencyTranslationGainLoss

-15000000

USD

CY2020Q4

us-gaap

Liability For Unpaid Claims And Claims Adjustment Expense Net

LiabilityForUnpaidClaimsAndClaimsAdjustmentExpenseNet

-430000000

USD

CY2019Q4

us-gaap

Liability For Unpaid Claims And Claims Adjustment Expense Net

LiabilityForUnpaidClaimsAndClaimsAdjustmentExpenseNet

-436000000

USD

CY2018Q4

us-gaap

Liability For Unpaid Claims And Claims Adjustment Expense Net

LiabilityForUnpaidClaimsAndClaimsAdjustmentExpenseNet

-130000000

USD

CY2020Q4

ambc

Impactof Vie Consolidationon Gross Lossand Loss Reserves

ImpactofVIEConsolidationonGrossLossandLossReserves

0

USD

CY2020Q4

ambc

Loss Reserves Ceded To Reinsurers

LossReservesCededToReinsurers

33000000

USD

CY2019Q4

ambc

Loss Reserves Ceded To Reinsurers

LossReservesCededToReinsurers

26000000

USD

CY2018Q4

ambc

Loss Reserves Ceded To Reinsurers

LossReservesCededToReinsurers

23000000

USD

CY2020Q4

us-gaap

Liability For Claims And Claims Adjustment Expense

LiabilityForClaimsAndClaimsAdjustmentExpense

-397000000

USD

CY2019Q4

us-gaap

Liability For Claims And Claims Adjustment Expense

LiabilityForClaimsAndClaimsAdjustmentExpense

-482000000

USD

CY2018Q4

us-gaap

Liability For Claims And Claims Adjustment Expense

LiabilityForClaimsAndClaimsAdjustmentExpense

-107000000

USD

CY2018Q1

ambc

Satisfactionanddischargeofsegregatedaccountdeferredamounts

3000000000

USD

CY2018Q1

ambc

Satisfactionanddischargeofsegregatedaccountdeferredinterestamounts

857000000

USD

CY2018Q1

ambc

Lossand Loss Expense Benefiton Settled Deferred Amounts

LossandLossExpenseBenefitonSettledDeferredAmounts

288000000

USD

CY2020

us-gaap

Reinsurance Effect On Claims And Benefits Incurred Amount Ceded

ReinsuranceEffectOnClaimsAndBenefitsIncurredAmountCeded

11000000

USD

CY2019

us-gaap

Reinsurance Effect On Claims And Benefits Incurred Amount Ceded

ReinsuranceEffectOnClaimsAndBenefitsIncurredAmountCeded

7000000

USD

CY2018

us-gaap

Reinsurance Effect On Claims And Benefits Incurred Amount Ceded

ReinsuranceEffectOnClaimsAndBenefitsIncurredAmountCeded

2000000

USD

CY2020

ambc

Net Incurred Rmbs Subrogation Recoveries

NetIncurredRMBSSubrogationRecoveries

23000000

USD

CY2019

ambc

Net Incurred Rmbs Subrogation Recoveries

NetIncurredRMBSSubrogationRecoveries

-42000000

USD

CY2018

ambc

Net Incurred Rmbs Subrogation Recoveries

NetIncurredRMBSSubrogationRecoveries

-62000000

USD

CY2020Q4

us-gaap

Reinsurance Recoverables Allowance

ReinsuranceRecoverablesAllowance

0

USD

CY2020Q4

ambc

Ceded Loss And Loss Expenses Paid Not Yet Recovered

CededLossAndLossExpensesPaidNotYetRecovered

1000000

USD

CY2019Q4

ambc

Ceded Loss And Loss Expenses Paid Not Yet Recovered

CededLossAndLossExpensesPaidNotYetRecovered

0

USD

CY2018Q4

ambc

Ceded Loss And Loss Expenses Paid Not Yet Recovered

CededLossAndLossExpensesPaidNotYetRecovered

1000000

USD

CY2020Q4

us-gaap

Schedule Of Insured Financial Obligations With Credit Deterioration Number Of Contracts Issued And Outstanding

ScheduleOfInsuredFinancialObligationsWithCreditDeteriorationNumberOfContractsIssuedAndOutstanding

232

Policies

CY2020

us-gaap

Insured Financial Obligations With Credit Deterioration Remaining Weighted Average Contract Period

InsuredFinancialObligationsWithCreditDeteriorationRemainingWeightedAverageContractPeriod

P14Y

CY2020Q4

us-gaap

Schedule Of Insured Financial Obligations With Credit Deterioration Insured Contractual Payments Outstanding Principal

ScheduleOfInsuredFinancialObligationsWithCreditDeteriorationInsuredContractualPaymentsOutstandingPrincipal

7573000000

USD

CY2020Q4

us-gaap

Schedule Of Insured Financial Obligations With Credit Deterioration Insured Contractual Payments Outstanding Interest

ScheduleOfInsuredFinancialObligationsWithCreditDeteriorationInsuredContractualPaymentsOutstandingInterest

3443000000

USD

CY2020Q4

us-gaap

Schedule Of Insured Financial Obligations With Credit Deterioration Insured Contractual Payments Outstanding

ScheduleOfInsuredFinancialObligationsWithCreditDeteriorationInsuredContractualPaymentsOutstanding

11016000000

USD

CY2020Q4

ambc

Schedule Of Insured Financial Obligations With Credit Deterioration Gross Undiscounted Claim Liability

ScheduleOfInsuredFinancialObligationsWithCreditDeteriorationGrossUndiscountedClaimLiability

-2395000000

USD

CY2020Q4

ambc

Schedule Of Insured Financial Obligations With Credit Deterioration Discount On Gross Claim Liability

ScheduleOfInsuredFinancialObligationsWithCreditDeteriorationDiscountOnGrossClaimLiability

-303000000

USD

CY2020Q4

us-gaap

Schedule Of Insured Financial Obligations With Credit Deterioration Gross Claim Liability

ScheduleOfInsuredFinancialObligationsWithCreditDeteriorationGrossClaimLiability

-2092000000

USD

CY2020Q4

ambc

Schedule Of Insured Financial Obligations With Credit Deterioration Reductions Of Gross Undiscounted Claim Liability Gross Undiscounted Rmbs Subrogation

ScheduleOfInsuredFinancialObligationsWithCreditDeteriorationReductionsOfGrossUndiscountedClaimLiabilityGrossUndiscountedRmbsSubrogation

1753000000

USD

CY2020Q4

ambc

Schedule Of Insured Financial Obligations With Credit Deterioration Reductions Of Gross Claim Liability Discount On Rmbs Subrogation

ScheduleOfInsuredFinancialObligationsWithCreditDeteriorationReductionsOfGrossClaimLiabilityDiscountOnRmbsSubrogation

3000000

USD

CY2020Q4

ambc

Schedule Of Insured Financial Obligations With Credit Deterioration Reductions Of Gross Claim Liability Rmbs Subrogation

ScheduleOfInsuredFinancialObligationsWithCreditDeteriorationReductionsOfGrossClaimLiabilityRmbsSubrogation

1751000000

USD

CY2020Q4

ambc

Schedule Of Insured Financial Obligations With Credit Deterioration Reductions Of Gross Undiscounted Claim Liability Gross Undiscounted Other Subrogation

ScheduleOfInsuredFinancialObligationsWithCreditDeteriorationReductionsOfGrossUndiscountedClaimLiabilityGrossUndiscountedOtherSubrogation

755000000

USD

CY2020Q4

ambc

Schedule Of Insured Financial Obligations With Credit Deterioration Reductions Of Gross Claim Liability Discount On Other Subrogation

ScheduleOfInsuredFinancialObligationsWithCreditDeteriorationReductionsOfGrossClaimLiabilityDiscountOnOtherSubrogation

20000000

USD

CY2020Q4

ambc

Schedule Of Insured Financial Obligations With Credit Deterioration Reductions Of Gross Claim Liability Other Subrogation

ScheduleOfInsuredFinancialObligationsWithCreditDeteriorationReductionsOfGrossClaimLiabilityOtherSubrogation

735000000

USD

CY2020Q4

us-gaap

Schedule Of Insured Financial Obligations With Credit Deterioration Net Claim Liability

ScheduleOfInsuredFinancialObligationsWithCreditDeteriorationNetClaimLiability

394000000

USD

CY2020Q4

us-gaap

Schedule Of Insured Financial Obligations With Credit Deterioration Statement Of Financial Position Unearned Premium Revenue

ScheduleOfInsuredFinancialObligationsWithCreditDeteriorationStatementOfFinancialPositionUnearnedPremiumRevenue

-72000000

USD

CY2020Q4

ambc

Schedule Of Insured Financial Obligations With Credit Deterioration Loss Adjustment Expenses Reserve

ScheduleOfInsuredFinancialObligationsWithCreditDeteriorationLossAdjustmentExpensesReserve

68000000

USD

CY2020Q4

us-gaap

Schedule Of Insured Financial Obligations With Credit Deterioration Statement Of Financial Position Claim Liability

ScheduleOfInsuredFinancialObligationsWithCreditDeteriorationStatementOfFinancialPositionClaimLiability

-397000000

USD

CY2020Q4

us-gaap

Schedule Of Insured Financial Obligations With Credit Deterioration Statement Of Financial Position Reinsurance Recoverable

ScheduleOfInsuredFinancialObligationsWithCreditDeteriorationStatementOfFinancialPositionReinsuranceRecoverable

33000000

USD

CY2020Q4

ambc

Loss Reserves Ceded To Reinsurers

LossReservesCededToReinsurers

33000000

USD

CY2020Q4

ambc

Ceded Loss And Loss Expenses Paid Not Yet Recovered

CededLossAndLossExpensesPaidNotYetRecovered

1000000

USD

CY2019Q4

us-gaap

Schedule Of Insured Financial Obligations With Credit Deterioration Number Of Contracts Issued And Outstanding

ScheduleOfInsuredFinancialObligationsWithCreditDeteriorationNumberOfContractsIssuedAndOutstanding

221

Policies

CY2019

us-gaap

Insured Financial Obligations With Credit Deterioration Remaining Weighted Average Contract Period

InsuredFinancialObligationsWithCreditDeteriorationRemainingWeightedAverageContractPeriod

P15Y

CY2019Q4

us-gaap

Schedule Of Insured Financial Obligations With Credit Deterioration Insured Contractual Payments Outstanding Principal

ScheduleOfInsuredFinancialObligationsWithCreditDeteriorationInsuredContractualPaymentsOutstandingPrincipal

6168000000

USD

CY2019Q4

us-gaap

Schedule Of Insured Financial Obligations With Credit Deterioration Insured Contractual Payments Outstanding Interest

ScheduleOfInsuredFinancialObligationsWithCreditDeteriorationInsuredContractualPaymentsOutstandingInterest

3029000000

USD

CY2019Q4

us-gaap

Schedule Of Insured Financial Obligations With Credit Deterioration Insured Contractual Payments Outstanding

ScheduleOfInsuredFinancialObligationsWithCreditDeteriorationInsuredContractualPaymentsOutstanding

9197000000

USD

CY2019Q4

ambc

Schedule Of Insured Financial Obligations With Credit Deterioration Gross Undiscounted Claim Liability

ScheduleOfInsuredFinancialObligationsWithCreditDeteriorationGrossUndiscountedClaimLiability

-2434000000

USD

CY2019Q4

ambc

Schedule Of Insured Financial Obligations With Credit Deterioration Discount On Gross Claim Liability

ScheduleOfInsuredFinancialObligationsWithCreditDeteriorationDiscountOnGrossClaimLiability

-541000000

USD

CY2019Q4

us-gaap

Schedule Of Insured Financial Obligations With Credit Deterioration Gross Claim Liability

ScheduleOfInsuredFinancialObligationsWithCreditDeteriorationGrossClaimLiability

-1893000000

USD

CY2019Q4

ambc

Schedule Of Insured Financial Obligations With Credit Deterioration Reductions Of Gross Undiscounted Claim Liability Gross Undiscounted Rmbs Subrogation

ScheduleOfInsuredFinancialObligationsWithCreditDeteriorationReductionsOfGrossUndiscountedClaimLiabilityGrossUndiscountedRmbsSubrogation

1777000000

USD

CY2019Q4

ambc

Schedule Of Insured Financial Obligations With Credit Deterioration Reductions Of Gross Claim Liability Discount On Rmbs Subrogation

ScheduleOfInsuredFinancialObligationsWithCreditDeteriorationReductionsOfGrossClaimLiabilityDiscountOnRmbsSubrogation

49000000

USD

CY2019Q4

ambc

Schedule Of Insured Financial Obligations With Credit Deterioration Reductions Of Gross Claim Liability Rmbs Subrogation

ScheduleOfInsuredFinancialObligationsWithCreditDeteriorationReductionsOfGrossClaimLiabilityRmbsSubrogation

1727000000

USD

CY2019Q4

ambc

Schedule Of Insured Financial Obligations With Credit Deterioration Reductions Of Gross Undiscounted Claim Liability Gross Undiscounted Other Subrogation

ScheduleOfInsuredFinancialObligationsWithCreditDeteriorationReductionsOfGrossUndiscountedClaimLiabilityGrossUndiscountedOtherSubrogation

720000000

USD

CY2019Q4

ambc

Schedule Of Insured Financial Obligations With Credit Deterioration Reductions Of Gross Claim Liability Discount On Other Subrogation

ScheduleOfInsuredFinancialObligationsWithCreditDeteriorationReductionsOfGrossClaimLiabilityDiscountOnOtherSubrogation

53000000

USD

CY2019Q4

ambc

Schedule Of Insured Financial Obligations With Credit Deterioration Reductions Of Gross Claim Liability Other Subrogation

ScheduleOfInsuredFinancialObligationsWithCreditDeteriorationReductionsOfGrossClaimLiabilityOtherSubrogation

666000000

USD

CY2019Q4

us-gaap

Schedule Of Insured Financial Obligations With Credit Deterioration Net Claim Liability

ScheduleOfInsuredFinancialObligationsWithCreditDeteriorationNetClaimLiability

501000000

USD

CY2019Q4

us-gaap

Schedule Of Insured Financial Obligations With Credit Deterioration Statement Of Financial Position Unearned Premium Revenue

ScheduleOfInsuredFinancialObligationsWithCreditDeteriorationStatementOfFinancialPositionUnearnedPremiumRevenue

-54000000

USD

CY2019Q4

ambc

Schedule Of Insured Financial Obligations With Credit Deterioration Loss Adjustment Expenses Reserve

ScheduleOfInsuredFinancialObligationsWithCreditDeteriorationLossAdjustmentExpensesReserve

73000000

USD

CY2019Q4

us-gaap

Schedule Of Insured Financial Obligations With Credit Deterioration Statement Of Financial Position Claim Liability

ScheduleOfInsuredFinancialObligationsWithCreditDeteriorationStatementOfFinancialPositionClaimLiability

-482000000

USD

CY2019Q4

us-gaap

Schedule Of Insured Financial Obligations With Credit Deterioration Statement Of Financial Position Reinsurance Recoverable

ScheduleOfInsuredFinancialObligationsWithCreditDeteriorationStatementOfFinancialPositionReinsuranceRecoverable

26000000

USD

CY2019Q4

ambc

Loss Reserves Ceded To Reinsurers

LossReservesCededToReinsurers

26000000

USD

CY2019Q4

ambc

Ceded Loss And Loss Expenses Paid Not Yet Recovered

CededLossAndLossExpensesPaidNotYetRecovered

0

USD

CY2020Q4

ambc

Public Finance Puerto Rico Net Par Outstanding

PublicFinancePuertoRicoNetParOutstanding

1070000000

USD

CY2020Q4

ambc

Possible Increasein Domestic Public Finance Loss Reserves

PossibleIncreaseinDomesticPublicFinanceLossReserves

1200000000

USD

CY2020Q4

us-gaap

Stockholders Equity Including Portion Attributable To Noncontrolling Interest

StockholdersEquityIncludingPortionAttributableToNoncontrollingInterest

1140000000

USD

CY2020Q4

ambc

Stockholders Equity After Possible Increasein Domestic Public Finance Loss Reserves

StockholdersEquityAfterPossibleIncreaseinDomesticPublicFinanceLossReserves

-60000000

USD

CY2019Q1

ambc

Percent Cash New Cofina Bonds Allocated Under Poa

PercentCashNewCOFINABondsAllocatedUnderPOA

0.93

CY2020Q4

ambc

Ambac Assurance Remaining Policy Obligations

AmbacAssuranceRemainingPolicyObligations

80000000

USD

CY2020Q4

ambc

Ambac Assurance Remaining Policy Obligations

AmbacAssuranceRemainingPolicyObligations

80000000

USD

CY2020Q4

ambc

Schedule Of Insured Financial Obligations With Credit Deterioration Reductions Of Gross Claim Liability Rmbs Subrogation

ScheduleOfInsuredFinancialObligationsWithCreditDeteriorationReductionsOfGrossClaimLiabilityRmbsSubrogation

1751000000

USD

CY2020Q4

ambc

Balance Of Rmbs Subrogation Recoveries Net Of Reinsurance

BalanceOfRmbsSubrogationRecoveriesNetOfReinsurance

-1725000000

USD

CY2019Q4

ambc

Schedule Of Insured Financial Obligations With Credit Deterioration Reductions Of Gross Claim Liability Rmbs Subrogation

ScheduleOfInsuredFinancialObligationsWithCreditDeteriorationReductionsOfGrossClaimLiabilityRmbsSubrogation

1727000000

USD

CY2019Q4

ambc

Balance Of Rmbs Subrogation Recoveries Net Of Reinsurance

BalanceOfRmbsSubrogationRecoveriesNetOfReinsurance

-1702000000

USD

CY2020Q4

ambc

Deferred Ceded Premiums And Reinsurance Recoverables

DeferredCededPremiumsAndReinsuranceRecoverables

103000000

USD

CY2020Q4

us-gaap

Reinsurance Payable

ReinsurancePayable

27000000

USD

CY2020Q4

us-gaap

Letters Of Credit Outstanding Amount

LettersOfCreditOutstandingAmount

117000000

USD

CY2020

ambc

Percentage Of Ceded Financial Guarantee Principal Outstanding

PercentageOfCededFinancialGuaranteePrincipalOutstanding

1

CY2020Q4

ambc

Unsecured Reinsurance Recoverables

UnsecuredReinsuranceRecoverables

34000000

USD

CY2020Q4

ambc

Reinsurance Recoverable Credit Exposure

ReinsuranceRecoverableCreditExposure

1000000

USD

CY2020Q4

us-gaap

Reinsurance Recoverables Allowance

ReinsuranceRecoverablesAllowance

0

USD

CY2020

us-gaap

Amortization Of Intangible Assets

AmortizationOfIntangibleAssets

57000000

USD

CY2019

us-gaap

Amortization Of Intangible Assets

AmortizationOfIntangibleAssets

295000000

USD

CY2018

us-gaap

Amortization Of Intangible Assets

AmortizationOfIntangibleAssets

107000000

USD

CY2020Q4

us-gaap

Intangible Assets Gross Excluding Goodwill

IntangibleAssetsGrossExcludingGoodwill

1281000000

USD

CY2019Q4

us-gaap

Intangible Assets Gross Excluding Goodwill

IntangibleAssetsGrossExcludingGoodwill

1273000000

USD

CY2020Q4

us-gaap

Finite Lived Intangible Assets Accumulated Amortization

FiniteLivedIntangibleAssetsAccumulatedAmortization

908000000

USD

CY2019Q4

us-gaap

Finite Lived Intangible Assets Accumulated Amortization

FiniteLivedIntangibleAssetsAccumulatedAmortization

847000000

USD

CY2019Q4

us-gaap

Intangible Assets Net Excluding Goodwill

IntangibleAssetsNetExcludingGoodwill

427000000

USD

CY2020

us-gaap

Acquired Finite Lived Intangible Assets Weighted Average Useful Life

AcquiredFiniteLivedIntangibleAssetsWeightedAverageUsefulLife

P7Y6M

CY2020Q4

ambc

Average Annual Rate Of Return

AverageAnnualRateOfReturn

0.0456

CY2019Q4

ambc

Average Annual Rate Of Return

AverageAnnualRateOfReturn

0.0543

CY2020

ambc

Prescribed Discount Rate Percentage

PrescribedDiscountRatePercentage

0.0510

CY2020

ambc

Quarterly Dividend Increase Limitation Percentage

QuarterlyDividendIncreaseLimitationPercentage

0.15

CY2019Q4

us-gaap

Fair Value Measurement With Unobservable Inputs Reconciliation Recurring Basis Asset Value

FairValueMeasurementWithUnobservableInputsReconciliationRecurringBasisAssetValue

72000000

USD

CY2018Q4

us-gaap

Fair Value Measurement With Unobservable Inputs Reconciliation Recurring Basis Asset Value

FairValueMeasurementWithUnobservableInputsReconciliationRecurringBasisAssetValue

72000000

USD

CY2020

us-gaap

Fair Value Measurement With Unobservable Inputs Reconciliation Recurring Basis Liability Gain Loss Included In Earnings

FairValueMeasurementWithUnobservableInputsReconciliationRecurringBasisLiabilityGainLossIncludedInEarnings

1000000

USD

CY2019

us-gaap

Fair Value Measurement With Unobservable Inputs Reconciliation Recurring Basis Liability Gain Loss Included In Earnings

FairValueMeasurementWithUnobservableInputsReconciliationRecurringBasisLiabilityGainLossIncludedInEarnings

2000000

USD

CY2020

us-gaap

Fair Value Measurement With Unobservable Inputs Reconciliation Recurring Basis Liability Gain Loss Included In Other Comprehensive Income

FairValueMeasurementWithUnobservableInputsReconciliationRecurringBasisLiabilityGainLossIncludedInOtherComprehensiveIncome

6000000

USD

CY2019

us-gaap

Fair Value Measurement With Unobservable Inputs Reconciliation Recurring Basis Liability Gain Loss Included In Other Comprehensive Income

FairValueMeasurementWithUnobservableInputsReconciliationRecurringBasisLiabilityGainLossIncludedInOtherComprehensiveIncome

0

USD

CY2020

us-gaap

Fair Value Measurement With Unobservable Inputs Reconciliation Recurring Basis Asset Purchases

FairValueMeasurementWithUnobservableInputsReconciliationRecurringBasisAssetPurchases

0

USD

CY2019

us-gaap

Fair Value Measurement With Unobservable Inputs Reconciliation Recurring Basis Asset Purchases

FairValueMeasurementWithUnobservableInputsReconciliationRecurringBasisAssetPurchases

0

USD

CY2020

us-gaap

Fair Value Measurement With Unobservable Inputs Reconciliation Recurring Basis Asset Issues

FairValueMeasurementWithUnobservableInputsReconciliationRecurringBasisAssetIssues

0

USD

CY2019

us-gaap

Fair Value Measurement With Unobservable Inputs Reconciliation Recurring Basis Asset Issues

FairValueMeasurementWithUnobservableInputsReconciliationRecurringBasisAssetIssues

0

USD

CY2020

us-gaap

Fair Value Measurement With Unobservable Inputs Reconciliation Recurring Basis Asset Sales

FairValueMeasurementWithUnobservableInputsReconciliationRecurringBasisAssetSales

0

USD

CY2019

us-gaap

Fair Value Measurement With Unobservable Inputs Reconciliation Recurring Basis Asset Sales

FairValueMeasurementWithUnobservableInputsReconciliationRecurringBasisAssetSales

0

USD

CY2020

us-gaap

Fair Value Measurement With Unobservable Inputs Reconciliation Recurring Basis Asset Settlements

FairValueMeasurementWithUnobservableInputsReconciliationRecurringBasisAssetSettlements

-1000000

USD

CY2019

us-gaap

Fair Value Measurement With Unobservable Inputs Reconciliation Recurring Basis Asset Settlements

FairValueMeasurementWithUnobservableInputsReconciliationRecurringBasisAssetSettlements

-2000000

USD

CY2020Q4

us-gaap

Fair Value Measurement With Unobservable Inputs Reconciliation Recurring Basis Asset Value

FairValueMeasurementWithUnobservableInputsReconciliationRecurringBasisAssetValue

78000000

USD

CY2019Q4

us-gaap

Fair Value Measurement With Unobservable Inputs Reconciliation Recurring Basis Asset Value

FairValueMeasurementWithUnobservableInputsReconciliationRecurringBasisAssetValue

72000000

USD

CY2020

us-gaap

Fair Value Liabilities Measured On Recurring Basis Change In Unrealized Gain Loss

FairValueLiabilitiesMeasuredOnRecurringBasisChangeInUnrealizedGainLoss

0

USD

us-gaap

Fair Value Liabilities Measured On Recurring Basis Change In Unrealized Gain Loss

FairValueLiabilitiesMeasuredOnRecurringBasisChangeInUnrealizedGainLoss

0

USD

CY2017Q4

us-gaap

Fair Value Measurement With Unobservable Inputs Reconciliation Recurring Basis Asset Value

FairValueMeasurementWithUnobservableInputsReconciliationRecurringBasisAssetValue

809000000

USD

CY2018

us-gaap

Fair Value Measurement With Unobservable Inputs Reconciliation Recurring Basis Liability Gain Loss Included In Earnings

FairValueMeasurementWithUnobservableInputsReconciliationRecurringBasisLiabilityGainLossIncludedInEarnings

36000000

USD

CY2018

us-gaap

Fair Value Measurement With Unobservable Inputs Reconciliation Recurring Basis Liability Gain Loss Included In Other Comprehensive Income

FairValueMeasurementWithUnobservableInputsReconciliationRecurringBasisLiabilityGainLossIncludedInOtherComprehensiveIncome

-53000000

USD

CY2018

us-gaap

Fair Value Measurement With Unobservable Inputs Reconciliation Recurring Basis Asset Purchases

FairValueMeasurementWithUnobservableInputsReconciliationRecurringBasisAssetPurchases

0

USD

CY2018

us-gaap

Fair Value Measurement With Unobservable Inputs Reconciliation Recurring Basis Asset Issues

FairValueMeasurementWithUnobservableInputsReconciliationRecurringBasisAssetIssues

0

USD

CY2018

us-gaap

Fair Value Measurement With Unobservable Inputs Reconciliation Recurring Basis Asset Sales

FairValueMeasurementWithUnobservableInputsReconciliationRecurringBasisAssetSales

0

USD

CY2018

us-gaap

Fair Value Measurement With Unobservable Inputs Reconciliation Recurring Basis Asset Settlements

FairValueMeasurementWithUnobservableInputsReconciliationRecurringBasisAssetSettlements

-714000000

USD

CY2018

us-gaap

Fair Value Measurement With Unobservable Inputs Reconciliation Recurring Basis Asset Transfers Out Of Level3

FairValueMeasurementWithUnobservableInputsReconciliationRecurringBasisAssetTransfersOutOfLevel3

-5000000

USD

CY2018Q4

us-gaap

Fair Value Measurement With Unobservable Inputs Reconciliation Recurring Basis Asset Value

FairValueMeasurementWithUnobservableInputsReconciliationRecurringBasisAssetValue

72000000

USD

CY2018

us-gaap

Fair Value Liabilities Measured On Recurring Basis Change In Unrealized Gain Loss

FairValueLiabilitiesMeasuredOnRecurringBasisChangeInUnrealizedGainLoss

0

USD

CY2020Q4

us-gaap

Available For Sale Securities Amortized Cost

AvailableForSaleSecuritiesAmortizedCost

2807000000

USD

CY2020Q4

us-gaap

Debt Securities Available For Sale Allowance For Credit Loss

DebtSecuritiesAvailableForSaleAllowanceForCreditLoss

0

USD

CY2020Q4

us-gaap

Available For Sale Debt Securities Accumulated Gross Unrealized Gain Before Tax

AvailableForSaleDebtSecuritiesAccumulatedGrossUnrealizedGainBeforeTax

149000000

USD

CY2020Q4

us-gaap

Available For Sale Securities Accumulated Gross Unrealized Loss Before Tax

AvailableForSaleSecuritiesAccumulatedGrossUnrealizedLossBeforeTax

8000000

USD

CY2020Q4

us-gaap

Available For Sale Securities Current

AvailableForSaleSecuritiesCurrent

2949000000

USD

CY2019Q4

us-gaap

Available For Sale Debt Securities Amortized Cost Basis

AvailableForSaleDebtSecuritiesAmortizedCostBasis

3187000000

USD

CY2019Q4

us-gaap

Available For Sale Debt Securities Accumulated Gross Unrealized Gain Before Tax

AvailableForSaleDebtSecuritiesAccumulatedGrossUnrealizedGainBeforeTax

132000000

USD

CY2019Q4

us-gaap

Available For Sale Debt Securities Accumulated Gross Unrealized Loss Before Tax

AvailableForSaleDebtSecuritiesAccumulatedGrossUnrealizedLossBeforeTax

5000000

USD

CY2019Q4

us-gaap

Available For Sale Securities Debt Securities

AvailableForSaleSecuritiesDebtSecurities

3314000000

USD

CY2019Q4

us-gaap

Accumulated Other Comprehensive Income Loss Other Than Temporary Impairment Not Credit Loss Net Of Tax Availableforsale Debt Securities

AccumulatedOtherComprehensiveIncomeLossOtherThanTemporaryImpairmentNotCreditLossNetOfTaxAvailableforsaleDebtSecurities

0

USD

CY2020Q4

us-gaap

Available For Sale Securities Debt Maturities Within One Year Amortized Cost

AvailableForSaleSecuritiesDebtMaturitiesWithinOneYearAmortizedCost

718000000

USD

CY2020Q4

us-gaap

Available For Sale Securities Debt Maturities Within One Year Fair Value

AvailableForSaleSecuritiesDebtMaturitiesWithinOneYearFairValue

719000000

USD

CY2020Q4

us-gaap

Available For Sale Securities Debt Maturities After One Through Five Years Amortized Cost

AvailableForSaleSecuritiesDebtMaturitiesAfterOneThroughFiveYearsAmortizedCost

873000000

USD

CY2020Q4

us-gaap

Available For Sale Securities Debt Maturities After One Through Five Years Fair Value

AvailableForSaleSecuritiesDebtMaturitiesAfterOneThroughFiveYearsFairValue

880000000

USD

CY2020Q4

us-gaap

Available For Sale Securities Debt Maturities After Five Through Ten Years Amortized Cost

AvailableForSaleSecuritiesDebtMaturitiesAfterFiveThroughTenYearsAmortizedCost

439000000

USD

CY2020Q4

us-gaap

Available For Sale Securities Debt Maturities After Five Through Ten Years Fair Value

AvailableForSaleSecuritiesDebtMaturitiesAfterFiveThroughTenYearsFairValue

459000000

USD

CY2020Q4

us-gaap

Available For Sale Securities Debt Maturities After Ten Years Amortized Cost

AvailableForSaleSecuritiesDebtMaturitiesAfterTenYearsAmortizedCost

184000000

USD

CY2020Q4

us-gaap

Available For Sale Securities Debt Maturities After Ten Years Fair Value

AvailableForSaleSecuritiesDebtMaturitiesAfterTenYearsFairValue

213000000

USD

CY2020Q4

us-gaap

Available For Sale Securities Debt Maturities Single Maturity Date Amortized Cost Basis

AvailableForSaleSecuritiesDebtMaturitiesSingleMaturityDateAmortizedCostBasis

2214000000

USD

CY2020Q4

us-gaap

Available For Sale Securities Debt Maturities Single Maturity Date

AvailableForSaleSecuritiesDebtMaturitiesSingleMaturityDate

2271000000

USD

CY2020Q4

us-gaap

Available For Sale Debt Securities Amortized Cost Basis

AvailableForSaleDebtSecuritiesAmortizedCostBasis

2807000000

USD

CY2020Q4

us-gaap

Available For Sale Securities Debt Securities

AvailableForSaleSecuritiesDebtSecurities

2949000000

USD

CY2020Q4

us-gaap

Debt Securities Available For Sale Continuous Unrealized Loss Position Less Than12 Months

DebtSecuritiesAvailableForSaleContinuousUnrealizedLossPositionLessThan12Months

816000000

USD

CY2020Q4

us-gaap

Debt Securities Available For Sale Continuous Unrealized Loss Position Less Than12 Months Accumulated Loss

DebtSecuritiesAvailableForSaleContinuousUnrealizedLossPositionLessThan12MonthsAccumulatedLoss

7000000

USD

CY2020Q4

us-gaap

Debt Securities Available For Sale Continuous Unrealized Loss Position12 Months Or Longer

DebtSecuritiesAvailableForSaleContinuousUnrealizedLossPosition12MonthsOrLonger

25000000

USD

CY2020Q4

us-gaap

Debt Securities Available For Sale Continuous Unrealized Loss Position12 Months Or Longer Accumulated Loss

DebtSecuritiesAvailableForSaleContinuousUnrealizedLossPosition12MonthsOrLongerAccumulatedLoss

0

USD

CY2020Q4

us-gaap

Debt Securities Available For Sale Unrealized Loss Position

DebtSecuritiesAvailableForSaleUnrealizedLossPosition

841000000

USD

CY2020Q4

us-gaap

Available For Sale Debt Securities Accumulated Gross Unrealized Loss Before Tax

AvailableForSaleDebtSecuritiesAccumulatedGrossUnrealizedLossBeforeTax

8000000

USD

CY2019Q4

us-gaap

Debt Securities Available For Sale Continuous Unrealized Loss Position Less Than12 Months

DebtSecuritiesAvailableForSaleContinuousUnrealizedLossPositionLessThan12Months

401000000

USD

CY2019Q4

us-gaap

Debt Securities Available For Sale Continuous Unrealized Loss Position Less Than12 Months Accumulated Loss

DebtSecuritiesAvailableForSaleContinuousUnrealizedLossPositionLessThan12MonthsAccumulatedLoss

4000000

USD

CY2019Q4

us-gaap

Debt Securities Available For Sale Continuous Unrealized Loss Position12 Months Or Longer

DebtSecuritiesAvailableForSaleContinuousUnrealizedLossPosition12MonthsOrLonger

88000000

USD

CY2019Q4

us-gaap

Debt Securities Available For Sale Continuous Unrealized Loss Position12 Months Or Longer Accumulated Loss

DebtSecuritiesAvailableForSaleContinuousUnrealizedLossPosition12MonthsOrLongerAccumulatedLoss

1000000

USD

CY2019Q4

us-gaap

Debt Securities Available For Sale Unrealized Loss Position

DebtSecuritiesAvailableForSaleUnrealizedLossPosition

489000000

USD

CY2019Q4

us-gaap

Available For Sale Debt Securities Accumulated Gross Unrealized Loss Before Tax

AvailableForSaleDebtSecuritiesAccumulatedGrossUnrealizedLossBeforeTax

5000000

USD

CY2020

us-gaap

Available For Sale Securities Gross Realized Gains

AvailableForSaleSecuritiesGrossRealizedGains

38000000

USD

CY2019

us-gaap

Available For Sale Securities Gross Realized Gains

AvailableForSaleSecuritiesGrossRealizedGains

64000000

USD

CY2018

us-gaap

Available For Sale Securities Gross Realized Gains

AvailableForSaleSecuritiesGrossRealizedGains

111000000

USD

CY2020

us-gaap

Available For Sale Securities Gross Realized Losses

AvailableForSaleSecuritiesGrossRealizedLosses

12000000

USD

CY2019

us-gaap

Available For Sale Securities Gross Realized Losses

AvailableForSaleSecuritiesGrossRealizedLosses

5000000

USD

CY2018

us-gaap

Available For Sale Securities Gross Realized Losses

AvailableForSaleSecuritiesGrossRealizedLosses

7000000

USD

CY2020

us-gaap

Debt Securities Available For Sale Allowance For Credit Loss Not To Sell Before Recovery Credit Loss Previously Recorded Expense Reversal

DebtSecuritiesAvailableForSaleAllowanceForCreditLossNotToSellBeforeRecoveryCreditLossPreviouslyRecordedExpenseReversal

0

USD

CY2019

us-gaap

Debt Securities Available For Sale Allowance For Credit Loss Not To Sell Before Recovery Credit Loss Previously Recorded Expense Reversal

DebtSecuritiesAvailableForSaleAllowanceForCreditLossNotToSellBeforeRecoveryCreditLossPreviouslyRecordedExpenseReversal

0

USD

CY2018

us-gaap

Debt Securities Available For Sale Allowance For Credit Loss Not To Sell Before Recovery Credit Loss Previously Recorded Expense Reversal

DebtSecuritiesAvailableForSaleAllowanceForCreditLossNotToSellBeforeRecoveryCreditLossPreviouslyRecordedExpenseReversal

0

USD

CY2020

us-gaap

Debt Securities Available For Sale Allowance For Credit Loss Sell Before Recovery

DebtSecuritiesAvailableForSaleAllowanceForCreditLossSellBeforeRecovery

0

USD

CY2019

us-gaap

Debt Securities Available For Sale Allowance For Credit Loss Sell Before Recovery

DebtSecuritiesAvailableForSaleAllowanceForCreditLossSellBeforeRecovery

0

USD

CY2018

us-gaap

Debt Securities Available For Sale Allowance For Credit Loss Sell Before Recovery

DebtSecuritiesAvailableForSaleAllowanceForCreditLossSellBeforeRecovery

-3000000

USD

CY2020

us-gaap

Availableforsale Securities Gross Realized Gain Loss Excluding Other Than Temporary Impairments

AvailableforsaleSecuritiesGrossRealizedGainLossExcludingOtherThanTemporaryImpairments

22000000

USD

CY2019

us-gaap

Availableforsale Securities Gross Realized Gain Loss Excluding Other Than Temporary Impairments

AvailableforsaleSecuritiesGrossRealizedGainLossExcludingOtherThanTemporaryImpairments

81000000

USD

CY2018

us-gaap

Availableforsale Securities Gross Realized Gain Loss Excluding Other Than Temporary Impairments

AvailableforsaleSecuritiesGrossRealizedGainLossExcludingOtherThanTemporaryImpairments

108000000

USD

CY2018Q4

us-gaap

Other Than Temporary Impairment Credit Losses Recognized In Earnings Credit Losses On Debt Securities Held

OtherThanTemporaryImpairmentCreditLossesRecognizedInEarningsCreditLossesOnDebtSecuritiesHeld

12000000

USD

CY2017Q4

us-gaap

Other Than Temporary Impairment Credit Losses Recognized In Earnings Credit Losses On Debt Securities Held

OtherThanTemporaryImpairmentCreditLossesRecognizedInEarningsCreditLossesOnDebtSecuritiesHeld

67000000

USD

CY2019

us-gaap

Other Than Temporary Impairment Credit Losses Recognized In Earnings Additions No Previous Impairment

OtherThanTemporaryImpairmentCreditLossesRecognizedInEarningsAdditionsNoPreviousImpairment

0

USD

CY2018

us-gaap

Other Than Temporary Impairment Credit Losses Recognized In Earnings Additions No Previous Impairment

OtherThanTemporaryImpairmentCreditLossesRecognizedInEarningsAdditionsNoPreviousImpairment

1000000

USD

CY2019

us-gaap

Other Than Temporary Impairment Credit Losses Recognized In Earnings Reductions Securities Sold

OtherThanTemporaryImpairmentCreditLossesRecognizedInEarningsReductionsSecuritiesSold

1000000

USD

CY2018

us-gaap

Other Than Temporary Impairment Credit Losses Recognized In Earnings Reductions Securities Sold

OtherThanTemporaryImpairmentCreditLossesRecognizedInEarningsReductionsSecuritiesSold

56000000

USD

CY2019Q4

us-gaap

Other Than Temporary Impairment Credit Losses Recognized In Earnings Credit Losses On Debt Securities Held

OtherThanTemporaryImpairmentCreditLossesRecognizedInEarningsCreditLossesOnDebtSecuritiesHeld

12000000

USD

CY2018Q4

us-gaap

Other Than Temporary Impairment Credit Losses Recognized In Earnings Credit Losses On Debt Securities Held

OtherThanTemporaryImpairmentCreditLossesRecognizedInEarningsCreditLossesOnDebtSecuritiesHeld

12000000

USD

CY2020Q4

us-gaap

Debt Securities Available For Sale Allowance For Credit Loss

DebtSecuritiesAvailableForSaleAllowanceForCreditLoss

0

USD

CY2020Q4

ambc

Fair Value Of Securities Deposited With Governmental Authorities

FairValueOfSecuritiesDepositedWithGovernmentalAuthorities

8000000

USD

CY2019Q4

ambc

Fair Value Of Securities Deposited With Governmental Authorities

FairValueOfSecuritiesDepositedWithGovernmentalAuthorities

6000000

USD

CY2020Q4

ambc

Fair Valueof Securities Depositedin Connectionwtih Letterof Credit

FairValueofSecuritiesDepositedinConnectionwtihLetterofCredit

1000000

USD

CY2020Q4

ambc

Market Valueof Secured Note Collateral

MarketValueofSecuredNoteCollateral

178000000

USD

CY2019Q4

ambc

Market Valueof Secured Note Collateral

MarketValueofSecuredNoteCollateral

197000000

USD

CY2020Q4

us-gaap

Derivative Fair Value Of Derivative Asset

DerivativeFairValueOfDerivativeAsset

93000000

USD

CY2020Q4

us-gaap

Derivative Fair Value Of Derivative Asset Amount Offset Against Collateral

DerivativeFairValueOfDerivativeAssetAmountOffsetAgainstCollateral

0

USD

CY2020Q4

us-gaap

Derivative Assets

DerivativeAssets

93000000

USD

CY2019

us-gaap

Trading Securities Realized Gain Loss

TradingSecuritiesRealizedGainLoss

7000000

USD

CY2018

us-gaap

Trading Securities Realized Gain Loss

TradingSecuritiesRealizedGainLoss

1000000

USD

CY2019

us-gaap

Investment Income Interest And Dividend

InvestmentIncomeInterestAndDividend

183000000

USD

CY2018

us-gaap

Investment Income Interest And Dividend

InvestmentIncomeInterestAndDividend

265000000

USD

CY2020

us-gaap

Investment Income Investment Expense

InvestmentIncomeInvestmentExpense

6000000

USD

CY2019

us-gaap

Investment Income Investment Expense

InvestmentIncomeInvestmentExpense

6000000

USD

CY2018

us-gaap

Investment Income Investment Expense

InvestmentIncomeInvestmentExpense

7000000

USD

CY2020

us-gaap

Interest And Dividend Income Securities Available For Sale

InterestAndDividendIncomeSecuritiesAvailableForSale

103000000

USD

CY2019

us-gaap

Interest And Dividend Income Securities Available For Sale

InterestAndDividendIncomeSecuritiesAvailableForSale

196000000

USD

CY2018

us-gaap

Interest And Dividend Income Securities Available For Sale

InterestAndDividendIncomeSecuritiesAvailableForSale

271000000

USD

CY2020

us-gaap

Net Investment Income

NetInvestmentIncome

122000000

USD

CY2019

us-gaap

Net Investment Income

NetInvestmentIncome

227000000

USD

CY2018

us-gaap

Net Investment Income

NetInvestmentIncome

273000000

USD

CY2020

us-gaap

Net Realized Or Unrealized Gain Loss On Trading Securities

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CY2019

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Net Realized Or Unrealized Gain Loss On Trading Securities

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CY2018

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Net Realized Or Unrealized Gain Loss On Trading Securities

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CY2020

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Trading Securities Realized Gain Loss

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CY2020Q4

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CY2020Q4

ambc

Derivative Assets Net Amount

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CY2020Q4

us-gaap

Derivative Fair Value Of Derivative Liability

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CY2020Q4

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Derivative Fair Value Of Derivative Liability Amount Offset Against Collateral

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CY2020Q4

us-gaap

Derivative Liabilities

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CY2020Q4

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113000000

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CY2020Q4

ambc

Derivative Liabilities Net Amount

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CY2019Q4

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Derivative Fair Value Of Derivative Asset

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CY2019Q4

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Derivative Fair Value Of Derivative Asset Amount Offset Against Collateral

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0

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CY2019Q4

us-gaap

Derivative Assets

DerivativeAssets

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CY2019Q4

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Derivative Fair Value Of Derivative Asset Amount Not Offset Against Collateral

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CY2019Q4

ambc

Derivative Assets Net Amount

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CY2019Q4

us-gaap

Derivative Fair Value Of Derivative Liability

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CY2019Q4

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Derivative Fair Value Of Derivative Liability Amount Offset Against Collateral

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CY2019Q4

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Derivative Liabilities

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Derivative Liabilities Gross Amount Of Collateral Cash And Securities Pledged Not Offset

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Derivative Liabilities Net Amount

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Derivative Collateral Right To Reclaim Cash

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Derivative Collateral Right To Reclaim Cash

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Derivative Gain Loss On Derivative Net

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CY2019

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Derivative Gain Loss On Derivative Net

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Derivative Gain Losson Derivatives Total Net

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CY2019

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Derivative Gain Losson Derivatives Total Net

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CY2018

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Derivative Gain Losson Derivatives Total Net

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us-gaap

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CY2019Q4

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Derivative Net Liability Position Aggregate Fair Value

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CY2020Q4

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Collateral Already Posted Aggregate Fair Value

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CY2019Q4

us-gaap

Collateral Already Posted Aggregate Fair Value

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CY2020Q4

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Long Term Debt Maturities Repayments Of Principal In Next Twelve Months

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CY2020Q4

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Long Term Debt Maturities Repayments Of Principal In Year Two

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CY2020Q4

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Long Term Debt Maturities Repayments Of Principal In Year Three

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CY2020Q4

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Long Term Debt Maturities Repayments Of Principal In Year Four

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CY2020Q4

us-gaap

Long Term Debt Maturities Repayments Of Principal In Year Five

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CY2020Q4

us-gaap

Long Term Debt Maturities Repayments Of Principal After Year Five

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CY2018Q1

ambc

One Time Interest Paymenton Surplus Notes

OneTimeInterestPaymentonSurplusNotes

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CY2018

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Gains Losses On Extinguishment Of Debt

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CY2013Q2

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Ambc Junior Surplus Notes Issued

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CY2018Q1

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Tier2 Note Securityin Rmbs Litigation Settlement Proceeds

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CY2020

us-gaap

Income Loss From Continuing Operations Before Income Taxes Domestic

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CY2019

us-gaap

Income Loss From Continuing Operations Before Income Taxes Domestic

IncomeLossFromContinuingOperationsBeforeIncomeTaxesDomestic

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CY2018

us-gaap

Income Loss From Continuing Operations Before Income Taxes Domestic

IncomeLossFromContinuingOperationsBeforeIncomeTaxesDomestic

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CY2020

us-gaap

Income Loss From Continuing Operations Before Income Taxes Foreign

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CY2019

us-gaap

Income Loss From Continuing Operations Before Income Taxes Foreign

IncomeLossFromContinuingOperationsBeforeIncomeTaxesForeign

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CY2018

us-gaap

Income Loss From Continuing Operations Before Income Taxes Foreign

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CY2020

us-gaap

Income Loss From Continuing Operations Before Income Taxes Minority Interest And Income Loss From Equity Method Investments

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Income Loss From Continuing Operations Before Income Taxes Minority Interest And Income Loss From Equity Method Investments

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us-gaap

Income Loss From Continuing Operations Before Income Taxes Minority Interest And Income Loss From Equity Method Investments

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CY2020

us-gaap

Current Federal Tax Expense Benefit

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CY2019

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Current Federal Tax Expense Benefit

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CY2018

us-gaap

Current Federal Tax Expense Benefit

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CY2020

us-gaap

Current State And Local Tax Expense Benefit

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CY2019

us-gaap

Current State And Local Tax Expense Benefit

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CY2018

us-gaap

Current State And Local Tax Expense Benefit

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CY2020

us-gaap

Current Foreign Tax Expense Benefit

CurrentForeignTaxExpenseBenefit

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CY2019

us-gaap

Current Foreign Tax Expense Benefit

CurrentForeignTaxExpenseBenefit

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CY2018

us-gaap

Current Foreign Tax Expense Benefit

CurrentForeignTaxExpenseBenefit

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CY2020

us-gaap

Current Income Tax Expense Benefit

CurrentIncomeTaxExpenseBenefit

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CY2019

us-gaap

Current Income Tax Expense Benefit

CurrentIncomeTaxExpenseBenefit

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CY2018

us-gaap

Current Income Tax Expense Benefit

CurrentIncomeTaxExpenseBenefit

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CY2020

us-gaap

Deferred Foreign Income Tax Expense Benefit

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CY2019

us-gaap

Deferred Income Tax Expense Benefit

DeferredIncomeTaxExpenseBenefit

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CY2019

us-gaap

Deferred Foreign Income Tax Expense Benefit

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CY2018

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Deferred Foreign Income Tax Expense Benefit

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CY2020

us-gaap

Deferred Income Tax Expense Benefit

DeferredIncomeTaxExpenseBenefit

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CY2018

us-gaap

Deferred Income Tax Expense Benefit

DeferredIncomeTaxExpenseBenefit

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CY2020

us-gaap

Income Tax Expense Benefit

IncomeTaxExpenseBenefit

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CY2019

us-gaap

Income Tax Expense Benefit

IncomeTaxExpenseBenefit

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CY2018

us-gaap

Income Tax Expense Benefit

IncomeTaxExpenseBenefit

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CY2020

us-gaap

Income Tax Expense Benefit

IncomeTaxExpenseBenefit

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CY2019

us-gaap

Income Tax Expense Benefit

IncomeTaxExpenseBenefit

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CY2018

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Income Tax Expense Benefit

IncomeTaxExpenseBenefit

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Net Unrealized Losses On Securities Tax Effect

NetUnrealizedLossesOnSecuritiesTaxEffect

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CY2019

ambc

Net Unrealized Losses On Securities Tax Effect

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CY2018

ambc

Net Unrealized Losses On Securities Tax Effect

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CY2020

ambc

Unrealized Losson Fx Tax Effect

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CY2019

ambc

Unrealized Losson Fx Tax Effect

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CY2018

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Unrealized Losson Fx Tax Effect

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CY2020

ambc

Valuation Allowances And Reserves Charged To Equity

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Valuation Allowances And Reserves Charged To Equity

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CY2018

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Valuation Allowances And Reserves Charged To Equity

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CY2020

us-gaap

Income Tax Effects Allocated Directly To Equity

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CY2019

us-gaap

Income Tax Effects Allocated Directly To Equity

IncomeTaxEffectsAllocatedDirectlyToEquity

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CY2018

us-gaap

Income Tax Effects Allocated Directly To Equity

IncomeTaxEffectsAllocatedDirectlyToEquity

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CY2020

us-gaap

Income Tax Effects Allocated Directly To Equity Other

IncomeTaxEffectsAllocatedDirectlyToEquityOther

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CY2019

us-gaap

Income Tax Effects Allocated Directly To Equity Other

IncomeTaxEffectsAllocatedDirectlyToEquityOther

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CY2018

us-gaap

Income Tax Effects Allocated Directly To Equity Other

IncomeTaxEffectsAllocatedDirectlyToEquityOther

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CY2020

us-gaap

Income Tax Reconciliation Income Tax Expense Benefit At Federal Statutory Income Tax Rate

IncomeTaxReconciliationIncomeTaxExpenseBenefitAtFederalStatutoryIncomeTaxRate

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CY2020

us-gaap

Effective Income Tax Rate Reconciliation At Federal Statutory Income Tax Rate

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us-gaap

Income Tax Reconciliation Income Tax Expense Benefit At Federal Statutory Income Tax Rate

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CY2019

us-gaap

Effective Income Tax Rate Reconciliation At Federal Statutory Income Tax Rate

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CY2018

us-gaap

Income Tax Reconciliation Income Tax Expense Benefit At Federal Statutory Income Tax Rate

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CY2018

us-gaap

Effective Income Tax Rate Reconciliation At Federal Statutory Income Tax Rate

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CY2020

us-gaap

Income Tax Reconciliation Tax Exempt Income

IncomeTaxReconciliationTaxExemptIncome

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CY2020

us-gaap

Effective Income Tax Rate Reconciliation Tax Exempt Income

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CY2019

us-gaap

Income Tax Reconciliation Tax Exempt Income

IncomeTaxReconciliationTaxExemptIncome

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CY2019

us-gaap

Effective Income Tax Rate Reconciliation Tax Exempt Income

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CY2018

us-gaap

Income Tax Reconciliation Tax Exempt Income

IncomeTaxReconciliationTaxExemptIncome

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CY2018

us-gaap

Effective Income Tax Rate Reconciliation Tax Exempt Income

EffectiveIncomeTaxRateReconciliationTaxExemptIncome

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CY2020

us-gaap

Income Tax Reconciliation Tax Contingencies Foreign

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CY2020

us-gaap

Effective Income Tax Rate Reconciliation Tax Contingencies Foreign

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CY2019

us-gaap

Income Tax Reconciliation Tax Contingencies Foreign

IncomeTaxReconciliationTaxContingenciesForeign

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CY2019

us-gaap

Effective Income Tax Rate Reconciliation Tax Contingencies Foreign

EffectiveIncomeTaxRateReconciliationTaxContingenciesForeign

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CY2018

us-gaap

Income Tax Reconciliation Tax Contingencies Foreign

IncomeTaxReconciliationTaxContingenciesForeign

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CY2018

us-gaap

Effective Income Tax Rate Reconciliation Tax Contingencies Foreign

EffectiveIncomeTaxRateReconciliationTaxContingenciesForeign

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CY2020

us-gaap

Income Tax Reconciliation Prior Year Income Taxes

IncomeTaxReconciliationPriorYearIncomeTaxes

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CY2020

us-gaap

Effective Income Tax Rate Reconciliation Prior Year Income Taxes

EffectiveIncomeTaxRateReconciliationPriorYearIncomeTaxes

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CY2019

us-gaap

Income Tax Reconciliation Prior Year Income Taxes

IncomeTaxReconciliationPriorYearIncomeTaxes

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CY2019

us-gaap

Effective Income Tax Rate Reconciliation Prior Year Income Taxes

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CY2018

us-gaap

Income Tax Reconciliation Prior Year Income Taxes

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CY2018

us-gaap

Effective Income Tax Rate Reconciliation Prior Year Income Taxes

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CY2020

us-gaap

Income Tax Reconciliation Change In Deferred Tax Assets Valuation Allowance

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CY2020

us-gaap

Effective Income Tax Rate Reconciliation Change In Deferred Tax Assets Valuation Allowance

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CY2019

us-gaap

Income Tax Reconciliation Change In Deferred Tax Assets Valuation Allowance

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CY2019

us-gaap

Effective Income Tax Rate Reconciliation Change In Deferred Tax Assets Valuation Allowance

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CY2018

us-gaap

Income Tax Reconciliation Change In Deferred Tax Assets Valuation Allowance

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CY2018

us-gaap

Effective Income Tax Rate Reconciliation Change In Deferred Tax Assets Valuation Allowance

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ambc

Income Tax Reconciliation Tax Bankruptcy Adjustments

IncomeTaxReconciliationTaxBankruptcyAdjustments

0

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CY2020

ambc

Effectiveincome Tax Reconciliation Tax Bankruptcy Adjustments

EffectiveincomeTaxReconciliationTaxBankruptcyAdjustments

0

CY2019

ambc

Income Tax Reconciliation Tax Bankruptcy Adjustments

IncomeTaxReconciliationTaxBankruptcyAdjustments

0

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CY2019

ambc

Effectiveincome Tax Reconciliation Tax Bankruptcy Adjustments

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CY2018

ambc

Income Tax Reconciliation Tax Bankruptcy Adjustments

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CY2018

ambc

Effectiveincome Tax Reconciliation Tax Bankruptcy Adjustments

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CY2020

us-gaap

Income Tax Reconciliation Other Adjustments

IncomeTaxReconciliationOtherAdjustments

0

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CY2020

us-gaap

Effective Income Tax Rate Reconciliation Other Adjustments

EffectiveIncomeTaxRateReconciliationOtherAdjustments

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CY2020Q4

ambc

Current Liabilities Variable Interest Entity

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CY2019Q4

ambc

Current Liabilities Variable Interest Entity

CurrentLiabilitiesVariableInterestEntity

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CY2020Q4

us-gaap

Deferred Tax Liabilities Other

DeferredTaxLiabilitiesOther

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CY2019

us-gaap

Income Tax Reconciliation Other Adjustments

IncomeTaxReconciliationOtherAdjustments

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CY2019

us-gaap

Effective Income Tax Rate Reconciliation Other Adjustments

EffectiveIncomeTaxRateReconciliationOtherAdjustments

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CY2018

us-gaap

Income Tax Reconciliation Other Adjustments

IncomeTaxReconciliationOtherAdjustments

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CY2018

us-gaap

Effective Income Tax Rate Reconciliation Other Adjustments

EffectiveIncomeTaxRateReconciliationOtherAdjustments

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CY2020

us-gaap

Income Tax Expense Benefit

IncomeTaxExpenseBenefit

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CY2020

us-gaap

Effective Income Tax Rate Continuing Operations

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CY2019

us-gaap

Income Tax Expense Benefit

IncomeTaxExpenseBenefit

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CY2019

us-gaap

Effective Income Tax Rate Continuing Operations

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CY2018

us-gaap

Income Tax Expense Benefit

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CY2018

us-gaap

Effective Income Tax Rate Continuing Operations

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CY2019Q4

us-gaap

Unrecognized Tax Benefits

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CY2018Q4

us-gaap

Unrecognized Tax Benefits

UnrecognizedTaxBenefits

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CY2017Q4

us-gaap

Unrecognized Tax Benefits

UnrecognizedTaxBenefits

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CY2019

us-gaap

Unrecognized Tax Benefits Increases Resulting From Prior Period Tax Positions

UnrecognizedTaxBenefitsIncreasesResultingFromPriorPeriodTaxPositions

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CY2018

us-gaap

Unrecognized Tax Benefits Increases Resulting From Prior Period Tax Positions

UnrecognizedTaxBenefitsIncreasesResultingFromPriorPeriodTaxPositions

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CY2020

us-gaap

Unrecognized Tax Benefits Increases Resulting From Prior Period Tax Positions

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0

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CY2020

us-gaap

Unrecognized Tax Benefits Decreases Resulting From Prior Period Tax Positions

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CY2019

us-gaap

Unrecognized Tax Benefits Decreases Resulting From Prior Period Tax Positions

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CY2018

us-gaap

Unrecognized Tax Benefits Decreases Resulting From Prior Period Tax Positions

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CY2020Q4

us-gaap

Unrecognized Tax Benefits

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CY2019Q4

us-gaap

Unrecognized Tax Benefits

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CY2018Q4

us-gaap

Unrecognized Tax Benefits

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CY2020Q4

us-gaap

Deferred Tax Liabilities Goodwill And Intangible Assets Intangible Assets

DeferredTaxLiabilitiesGoodwillAndIntangibleAssetsIntangibleAssets

78000000

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CY2019Q4

us-gaap

Deferred Tax Liabilities Goodwill And Intangible Assets Intangible Assets

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90000000

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CY2020Q4

ambc

Deferred Tax Liabilities Unearned Premium Revenue

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CY2019Q4

ambc

Deferred Tax Liabilities Unearned Premium Revenue

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CY2020Q4

us-gaap

Deferred Tax Liabilities Investments

DeferredTaxLiabilitiesInvestments

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CY2019Q4

us-gaap

Deferred Tax Liabilities Investments

DeferredTaxLiabilitiesInvestments

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CY2019Q4

us-gaap

Deferred Tax Liabilities Other

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CY2020Q4

us-gaap

Deferred Tax Liabilities Gross Noncurrent

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CY2019Q4

us-gaap

Deferred Tax Liabilities Gross Noncurrent

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183000000

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CY2020Q4

us-gaap

Deferred Tax Assets Operating Loss Carryforwards

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CY2019Q4

us-gaap

Deferred Tax Assets Operating Loss Carryforwards

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CY2020Q4

us-gaap

Deferred Tax Assets Tax Deferred Expense Reserves And Accruals Loss Reserves

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CY2019Q4

us-gaap

Deferred Tax Assets Tax Deferred Expense Reserves And Accruals Loss Reserves

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CY2020Q4

ambc

Deferred Tax Assets Debentures

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ambc

Deferred Tax Assets Debentures

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CY2020Q4

us-gaap

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us-gaap

Deferred Tax Assets Tax Deferred Expense Compensation And Benefits Employee Compensation

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CY2020Q4

us-gaap

Deferred Tax Assets Other

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CY2019Q4

us-gaap

Deferred Tax Assets Other

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CY2020Q4

us-gaap

Deferred Tax Assets Gross

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CY2019Q4

us-gaap

Deferred Tax Assets Gross

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CY2020Q4

us-gaap

Deferred Tax Assets Valuation Allowance

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CY2019Q4

us-gaap

Deferred Tax Assets Valuation Allowance

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CY2020Q4

us-gaap

Deferred Tax Assets Net

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CY2019Q4

us-gaap

Deferred Tax Assets Net

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CY2020Q4

us-gaap

Deferred Tax Liabilities

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CY2019Q4

us-gaap

Deferred Tax Liabilities

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CY2020Q4

us-gaap

Deferred Tax Liabilities

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CY2020

ambc

Amount Of Nol Reallocated From Aac To Afg

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CY2020

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Tolling Payments Paid By Aac To Afg

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CY2020

us-gaap

Postemployment Benefits Period Expense

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CY2019

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Postemployment Benefits Period Expense

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CY2018

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Postemployment Benefits Period Expense

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USD

CY2020Q4

us-gaap

Postemployment Benefits Liability Current And Noncurrent

PostemploymentBenefitsLiabilityCurrentAndNoncurrent

10000000

USD

CY2020Q4

us-gaap

Defined Benefit Plan Expected Future Benefit Payments Next Twelve Months

DefinedBenefitPlanExpectedFutureBenefitPaymentsNextTwelveMonths

0

USD

CY2020Q4

us-gaap

Defined Benefit Plan Expected Future Benefit Payments Year Two

DefinedBenefitPlanExpectedFutureBenefitPaymentsYearTwo

0

USD

CY2020Q4

us-gaap

Defined Benefit Plan Expected Future Benefit Payments Year Three

DefinedBenefitPlanExpectedFutureBenefitPaymentsYearThree

0

USD

CY2020Q4

us-gaap

Defined Benefit Plan Expected Future Benefit Payments Year Four

DefinedBenefitPlanExpectedFutureBenefitPaymentsYearFour

0

USD

CY2020Q4

us-gaap

Defined Benefit Plan Expected Future Benefit Payments Year Five

DefinedBenefitPlanExpectedFutureBenefitPaymentsYearFive

1000000

USD

CY2020Q4

us-gaap

Defined Benefit Plan Expected Future Benefit Payments Five Fiscal Years Thereafter

DefinedBenefitPlanExpectedFutureBenefitPaymentsFiveFiscalYearsThereafter

3000000

USD

CY2020Q4

us-gaap

Defined Benefit Plan Benefit Obligation

DefinedBenefitPlanBenefitObligation

5000000

USD

CY2020Q4

us-gaap

Defined Benefit Plan Assumptions Used Calculating Benefit Obligation Discount Rate

DefinedBenefitPlanAssumptionsUsedCalculatingBenefitObligationDiscountRate

0.0225

CY2019Q4

us-gaap

Defined Benefit Plan Assumptions Used Calculating Benefit Obligation Discount Rate

DefinedBenefitPlanAssumptionsUsedCalculatingBenefitObligationDiscountRate

0.0300

CY2020

us-gaap

Defined Contribution Plan Maximum Annual Contributions Per Employee Percent

DefinedContributionPlanMaximumAnnualContributionsPerEmployeePercent

0.03

CY2020

us-gaap

Defined Contribution Plan Cost Recognized

DefinedContributionPlanCostRecognized

1000000

USD

CY2019

us-gaap

Defined Contribution Plan Cost Recognized

DefinedContributionPlanCostRecognized

1000000

USD

CY2018

us-gaap

Defined Contribution Plan Cost Recognized

DefinedContributionPlanCostRecognized

1000000

USD

CY2020Q4

us-gaap

Share Based Compensation Arrangement By Share Based Payment Award Number Of Shares Available For Grant

ShareBasedCompensationArrangementByShareBasedPaymentAwardNumberOfSharesAvailableForGrant

2096292

shares

CY2020Q4

ambc

Share Based Compensation Arrangement Shares Availablefor Future Issuanceat Target

ShareBasedCompensationArrangementSharesAvailableforFutureIssuanceatTarget

3058603

shares

CY2020

us-gaap

Allocated Share Based Compensation Expense

AllocatedShareBasedCompensationExpense

11000000

USD

CY2019

us-gaap

Allocated Share Based Compensation Expense

AllocatedShareBasedCompensationExpense

12000000

USD

CY2018

us-gaap

Allocated Share Based Compensation Expense

AllocatedShareBasedCompensationExpense

12000000

USD

CY2020

us-gaap

Allocated Share Based Compensation Expense Net Of Tax

AllocatedShareBasedCompensationExpenseNetOfTax

11000000

USD

CY2019

us-gaap

Allocated Share Based Compensation Expense Net Of Tax

AllocatedShareBasedCompensationExpenseNetOfTax

12000000

USD

CY2018

us-gaap

Allocated Share Based Compensation Expense Net Of Tax

AllocatedShareBasedCompensationExpenseNetOfTax

12000000

USD

CY2020

us-gaap

Sharebased Compensation Arrangement By Sharebased Payment Award Expiration Period

SharebasedCompensationArrangementBySharebasedPaymentAwardExpirationPeriod

P7Y

CY2019Q4

us-gaap

Share Based Compensation Arrangement By Share Based Payment Award Options Outstanding Number

ShareBasedCompensationArrangementByShareBasedPaymentAwardOptionsOutstandingNumber

16667

shares

CY2019Q4

us-gaap

Share Based Compensation Arrangement By Share Based Payment Award Options Outstanding Weighted Average Exercise Price

ShareBasedCompensationArrangementByShareBasedPaymentAwardOptionsOutstandingWeightedAverageExercisePrice

20.63

CY2020

us-gaap

Share Based Compensation Arrangement By Share Based Payment Award Options Grants In Period

ShareBasedCompensationArrangementByShareBasedPaymentAwardOptionsGrantsInPeriod

0

shares

CY2020

us-gaap

Share Based Compensation Arrangements By Share Based Payment Award Options Grants In Period Weighted Average Exercise Price

ShareBasedCompensationArrangementsByShareBasedPaymentAwardOptionsGrantsInPeriodWeightedAverageExercisePrice

0

CY2020

us-gaap

Stock Issued During Period Shares Stock Options Exercised

StockIssuedDuringPeriodSharesStockOptionsExercised

0

shares

CY2020

us-gaap

Share Based Compensation Arrangements By Share Based Payment Award Options Exercises In Period Weighted Average Exercise Price

ShareBasedCompensationArrangementsByShareBasedPaymentAwardOptionsExercisesInPeriodWeightedAverageExercisePrice

0

CY2020

us-gaap

Share Based Compensation Arrangement By Share Based Payment Award Options Forfeitures And Expirations In Period

ShareBasedCompensationArrangementByShareBasedPaymentAwardOptionsForfeituresAndExpirationsInPeriod

-16667

shares

CY2020

us-gaap

Share Based Compensation Arrangement By Share Based Payment Award Options Forfeitures And Expirations In Period Weighted Average Exercise Price

ShareBasedCompensationArrangementByShareBasedPaymentAwardOptionsForfeituresAndExpirationsInPeriodWeightedAverageExercisePrice

20.63

CY2020Q4

us-gaap

Share Based Compensation Arrangement By Share Based Payment Award Options Outstanding Number

ShareBasedCompensationArrangementByShareBasedPaymentAwardOptionsOutstandingNumber

0

shares

CY2020Q4

us-gaap

Share Based Compensation Arrangement By Share Based Payment Award Options Outstanding Weighted Average Exercise Price

ShareBasedCompensationArrangementByShareBasedPaymentAwardOptionsOutstandingWeightedAverageExercisePrice

0

CY2020Q4

us-gaap

Share Based Compensation Arrangement By Share Based Payment Award Options Outstanding Intrinsic Value

ShareBasedCompensationArrangementByShareBasedPaymentAwardOptionsOutstandingIntrinsicValue

0

USD

CY2020

us-gaap

Sharebased Compensation Arrangement By Sharebased Payment Award Options Outstanding Weighted Average Remaining Contractual Term2

SharebasedCompensationArrangementBySharebasedPaymentAwardOptionsOutstandingWeightedAverageRemainingContractualTerm2

P0Y

CY2020Q4

us-gaap

Share Based Compensation Arrangement By Share Based Payment Award Options Exercisable Number

ShareBasedCompensationArrangementByShareBasedPaymentAwardOptionsExercisableNumber

0

shares

CY2020Q4

us-gaap

Share Based Compensation Arrangement By Share Based Payment Award Options Exercisable Weighted Average Exercise Price

ShareBasedCompensationArrangementByShareBasedPaymentAwardOptionsExercisableWeightedAverageExercisePrice

0

CY2020Q4

us-gaap

Sharebased Compensation Arrangement By Sharebased Payment Award Options Exercisable Intrinsic Value1

SharebasedCompensationArrangementBySharebasedPaymentAwardOptionsExercisableIntrinsicValue1

0

USD

CY2020

us-gaap

Sharebased Compensation Arrangement By Sharebased Payment Award Options Exercisable Weighted Average Remaining Contractual Term1

SharebasedCompensationArrangementBySharebasedPaymentAwardOptionsExercisableWeightedAverageRemainingContractualTerm1

P0Y

CY2019

us-gaap

Stock Issued During Period Shares Stock Options Exercised

StockIssuedDuringPeriodSharesStockOptionsExercised

0

shares

CY2020

us-gaap

Stock Issued During Period Shares Stock Options Exercised

StockIssuedDuringPeriodSharesStockOptionsExercised

0

shares

CY2018

us-gaap

Stock Issued During Period Shares Stock Options Exercised

StockIssuedDuringPeriodSharesStockOptionsExercised

0

shares

CY2020Q4

us-gaap

Share Based Compensation Arrangement By Share Based Payment Award Equity Instruments Other Than Options Nonvested Number

ShareBasedCompensationArrangementByShareBasedPaymentAwardEquityInstrumentsOtherThanOptionsNonvestedNumber

345302

shares

CY2020Q4

ambc

Share Based Compensation Arrangement By Share Based Payment Award Equity Instruments Restricted Stock Units Vested Number

ShareBasedCompensationArrangementByShareBasedPaymentAwardEquityInstrumentsRestrictedStockUnitsVestedNumber

428355

shares

CY2019Q4

us-gaap

Share Based Compensation Arrangement By Share Based Payment Award Equity Instruments Other Than Options Nonvested Number

ShareBasedCompensationArrangementByShareBasedPaymentAwardEquityInstrumentsOtherThanOptionsNonvestedNumber

248942

shares

CY2019Q4

ambc

Share Based Compensation Arrangement By Share Based Payment Award Equity Instruments Restricted Stock Units Vested Number

ShareBasedCompensationArrangementByShareBasedPaymentAwardEquityInstrumentsRestrictedStockUnitsVestedNumber

453637

shares

CY2020Q4

ambc

Total Shareholder Return Modifier

TotalShareholderReturnModifier

0.10

CY2020

us-gaap

Operating Lease Expense

OperatingLeaseExpense

4000000

USD

CY2019

us-gaap

Operating Lease Expense

OperatingLeaseExpense

7000000

USD

CY2020

us-gaap

Variable Lease Cost

VariableLeaseCost

0

USD

CY2019

us-gaap

Variable Lease Cost

VariableLeaseCost

0

USD

CY2020

us-gaap

Sublease Income

SubleaseIncome

-1000000

USD

CY2019

us-gaap

Sublease Income

SubleaseIncome

-1000000

USD

CY2020

us-gaap

Lease Cost

LeaseCost

4000000

USD

CY2019

us-gaap

Lease Cost

LeaseCost

7000000

USD

CY2020

us-gaap

Operating Lease Payments

OperatingLeasePayments

4000000

USD

CY2019

us-gaap

Operating Lease Payments

OperatingLeasePayments

6000000

USD

CY2020

us-gaap

Right Of Use Asset Obtained In Exchange For Operating Lease Liability

RightOfUseAssetObtainedInExchangeForOperatingLeaseLiability

0

USD

CY2019

us-gaap

Right Of Use Asset Obtained In Exchange For Operating Lease Liability

RightOfUseAssetObtainedInExchangeForOperatingLeaseLiability

30000000

USD

CY2018Q4

us-gaap

Operating Lease Right Of Use Asset

OperatingLeaseRightOfUseAsset

14000000

USD

CY2020Q4

us-gaap

Operating Lease Right Of Use Asset

OperatingLeaseRightOfUseAsset

25000000

USD

CY2019Q4

us-gaap

Operating Lease Right Of Use Asset

OperatingLeaseRightOfUseAsset

25000000

USD

CY2020Q4

us-gaap

Operating Lease Liability

OperatingLeaseLiability

30000000

USD

CY2019Q4

us-gaap

Operating Lease Liability

OperatingLeaseLiability

29000000

USD

CY2020Q4

us-gaap

Operating Lease Weighted Average Remaining Lease Term1

OperatingLeaseWeightedAverageRemainingLeaseTerm1

P8Y8M12D

CY2019Q4

us-gaap

Operating Lease Weighted Average Remaining Lease Term1

OperatingLeaseWeightedAverageRemainingLeaseTerm1

P9Y10M24D

CY2020Q4

us-gaap

Operating Lease Weighted Average Discount Rate Percent

OperatingLeaseWeightedAverageDiscountRatePercent

0.077

CY2019Q4

us-gaap

Operating Lease Weighted Average Discount Rate Percent

OperatingLeaseWeightedAverageDiscountRatePercent

0.079

CY2020Q4

us-gaap

Lessee Operating Lease Liability Payments Due Next Twelve Months

LesseeOperatingLeaseLiabilityPaymentsDueNextTwelveMonths

5000000

USD

CY2020Q4

us-gaap

Lessee Operating Lease Liability Payments Due Year Two

LesseeOperatingLeaseLiabilityPaymentsDueYearTwo

5000000

USD

CY2020Q4

us-gaap

Lessee Operating Lease Liability Payments Due Year Three

LesseeOperatingLeaseLiabilityPaymentsDueYearThree

5000000

USD

CY2020Q4

us-gaap

Lessee Operating Lease Liability Payments Due Year Four

LesseeOperatingLeaseLiabilityPaymentsDueYearFour

5000000

USD

CY2020Q4

us-gaap

Lessee Operating Lease Liability Payments Due Year Five

LesseeOperatingLeaseLiabilityPaymentsDueYearFive

5000000

USD

CY2020Q4

us-gaap

Lessee Operating Lease Liability Payments Due After Year Five

LesseeOperatingLeaseLiabilityPaymentsDueAfterYearFive

18000000

USD

CY2020Q4

us-gaap

Lessee Operating Lease Liability Payments Due

LesseeOperatingLeaseLiabilityPaymentsDue

41000000

USD

CY2020Q4

us-gaap

Lessee Operating Lease Liability Undiscounted Excess Amount

LesseeOperatingLeaseLiabilityUndiscountedExcessAmount

-11000000

USD

CY2020Q4

us-gaap

Operating Lease Liability

OperatingLeaseLiability

30000000

USD

CY2020Q4

us-gaap

Lessor Operating Lease Term Of Contract

LessorOperatingLeaseTermOfContract

P9Y

CY2020Q4

us-gaap

Operating Leases Future Minimum Payments Receivable Remainder Of Fiscal Year

OperatingLeasesFutureMinimumPaymentsReceivableRemainderOfFiscalYear

1000000

USD

CY2020Q4

us-gaap

Operating Leases Future Minimum Payments Receivable In Two Years

OperatingLeasesFutureMinimumPaymentsReceivableInTwoYears

1000000

USD

CY2020Q4

us-gaap

Operating Leases Future Minimum Payments Receivable In Three Years

OperatingLeasesFutureMinimumPaymentsReceivableInThreeYears

1000000

USD

CY2020Q4

us-gaap

Operating Leases Future Minimum Payments Receivable In Four Years

OperatingLeasesFutureMinimumPaymentsReceivableInFourYears

1000000

USD

CY2020Q4

us-gaap

Operating Leases Future Minimum Payments Receivable In Five Years

OperatingLeasesFutureMinimumPaymentsReceivableInFiveYears

1000000

USD

CY2020Q4

us-gaap

Operating Leases Future Minimum Payments Due Thereafter

OperatingLeasesFutureMinimumPaymentsDueThereafter

5000000

USD

CY2020Q4

us-gaap

Lessor Operating Lease Payments To Be Received

LessorOperatingLeasePaymentsToBeReceived

11000000

USD

CY2020Q1

us-gaap

Premiums Written Gross

PremiumsWrittenGross

11000000

USD

CY2020Q2

us-gaap

Premiums Written Gross

PremiumsWrittenGross

1000000

USD

CY2020Q3

us-gaap

Premiums Written Gross

PremiumsWrittenGross

13000000

USD

CY2020Q4

us-gaap

Premiums Written Gross

PremiumsWrittenGross

1000000

USD

CY2019Q1

us-gaap

Premiums Written Gross

PremiumsWrittenGross

3000000

USD

CY2019Q2

us-gaap

Premiums Written Gross

PremiumsWrittenGross

21000000

USD

CY2019Q3

us-gaap

Premiums Written Gross

PremiumsWrittenGross

13000000

USD

CY2019Q4

us-gaap

Premiums Written Gross

PremiumsWrittenGross

-2000000

USD

CY2020Q1

us-gaap

Premiums Earned Net Financial Guarantee Insurance Contracts

PremiumsEarnedNetFinancialGuaranteeInsuranceContracts

10000000

USD

CY2020Q2

us-gaap

Premiums Earned Net Financial Guarantee Insurance Contracts

PremiumsEarnedNetFinancialGuaranteeInsuranceContracts

11000000

USD

CY2020Q3

us-gaap

Premiums Earned Net Financial Guarantee Insurance Contracts

PremiumsEarnedNetFinancialGuaranteeInsuranceContracts

15000000

USD

CY2020Q4

us-gaap

Premiums Earned Net Financial Guarantee Insurance Contracts

PremiumsEarnedNetFinancialGuaranteeInsuranceContracts

18000000

USD

CY2019Q1

us-gaap

Premiums Earned Net Financial Guarantee Insurance Contracts

PremiumsEarnedNetFinancialGuaranteeInsuranceContracts

28000000

USD

CY2019Q2

us-gaap

Premiums Earned Net Financial Guarantee Insurance Contracts

PremiumsEarnedNetFinancialGuaranteeInsuranceContracts

8000000

USD

CY2019Q3

us-gaap

Premiums Earned Net Financial Guarantee Insurance Contracts

PremiumsEarnedNetFinancialGuaranteeInsuranceContracts

10000000

USD

CY2019Q4

us-gaap

Premiums Earned Net Financial Guarantee Insurance Contracts

PremiumsEarnedNetFinancialGuaranteeInsuranceContracts

20000000

USD

CY2020Q1

us-gaap

Net Investment Income

NetInvestmentIncome

-21000000

USD

CY2020Q2

us-gaap

Net Investment Income

NetInvestmentIncome

52000000

USD

CY2020Q3

us-gaap

Net Investment Income

NetInvestmentIncome

37000000

USD

CY2020Q4

us-gaap

Net Investment Income

NetInvestmentIncome

53000000

USD

CY2019Q1

us-gaap

Net Investment Income

NetInvestmentIncome

55000000

USD

CY2019Q2

us-gaap

Net Investment Income

NetInvestmentIncome

86000000

USD

CY2019Q3

us-gaap

Net Investment Income

NetInvestmentIncome

45000000

USD

CY2019Q4

us-gaap

Net Investment Income

NetInvestmentIncome

42000000

USD

CY2020Q1

us-gaap

Realized Investment Gains Losses

RealizedInvestmentGainsLosses

8000000

USD

CY2020Q2

us-gaap

Realized Investment Gains Losses

RealizedInvestmentGainsLosses

10000000

USD

CY2020Q3

us-gaap

Realized Investment Gains Losses

RealizedInvestmentGainsLosses

2000000

USD

CY2020Q4

us-gaap

Realized Investment Gains Losses

RealizedInvestmentGainsLosses

2000000

USD

CY2019Q1

us-gaap

Realized Investment Gains Losses

RealizedInvestmentGainsLosses

17000000

USD

CY2019Q2

us-gaap

Realized Investment Gains Losses

RealizedInvestmentGainsLosses

36000000

USD

CY2019Q3

us-gaap

Realized Investment Gains Losses

RealizedInvestmentGainsLosses

18000000

USD

CY2019Q4

us-gaap

Realized Investment Gains Losses

RealizedInvestmentGainsLosses

9000000

USD

CY2020Q1

us-gaap

Derivative Gain Loss On Derivative Net

DerivativeGainLossOnDerivativeNet

-70000000

USD

CY2020Q2

us-gaap

Derivative Gain Loss On Derivative Net

DerivativeGainLossOnDerivativeNet

2000000

USD

CY2020Q3

us-gaap

Derivative Gain Loss On Derivative Net

DerivativeGainLossOnDerivativeNet

7000000

USD

CY2020Q4

us-gaap

Derivative Gain Loss On Derivative Net

DerivativeGainLossOnDerivativeNet

12000000

USD

CY2019Q1

us-gaap

Derivative Gain Loss On Derivative Net

DerivativeGainLossOnDerivativeNet

-16000000

USD

CY2019Q2

us-gaap

Derivative Gain Loss On Derivative Net

DerivativeGainLossOnDerivativeNet

-35000000

USD

CY2019Q3

us-gaap

Derivative Gain Loss On Derivative Net

DerivativeGainLossOnDerivativeNet

-10000000

USD

CY2019Q4

us-gaap

Derivative Gain Loss On Derivative Net

DerivativeGainLossOnDerivativeNet

12000000

USD

CY2020Q1

us-gaap

Other Income

OtherIncome

0

USD

CY2020Q2

us-gaap

Income Loss From Continuing Operations Before Income Taxes Minority Interest And Income Loss From Equity Method Investments

IncomeLossFromContinuingOperationsBeforeIncomeTaxesMinorityInterestAndIncomeLossFromEquityMethodInvestments

-33000000

USD

CY2020Q3

us-gaap

Income Loss From Continuing Operations Before Income Taxes Minority Interest And Income Loss From Equity Method Investments

IncomeLossFromContinuingOperationsBeforeIncomeTaxesMinorityInterestAndIncomeLossFromEquityMethodInvestments

-108000000

USD

CY2020Q2

us-gaap

Other Income

OtherIncome

0

USD

CY2020Q3

us-gaap

Other Income

OtherIncome

2000000

USD

CY2020Q4

us-gaap

Other Income

OtherIncome

1000000

USD

CY2019Q1

us-gaap

Other Income

OtherIncome

1000000

USD

CY2019Q2

us-gaap

Other Income

OtherIncome

-9000000

USD

CY2019Q3

us-gaap

Other Income

OtherIncome

141000000

USD

CY2019Q4

us-gaap

Other Income

OtherIncome

1000000

USD

CY2020Q1

us-gaap

Variable Interest Entity Activity Between Vie And Entity Operating Income Or Loss

VariableInterestEntityActivityBetweenVIEAndEntityOperatingIncomeOrLoss

3000000

USD

CY2020Q2

us-gaap

Variable Interest Entity Activity Between Vie And Entity Operating Income Or Loss

VariableInterestEntityActivityBetweenVIEAndEntityOperatingIncomeOrLoss

0

USD

CY2020Q3

us-gaap

Variable Interest Entity Activity Between Vie And Entity Operating Income Or Loss

VariableInterestEntityActivityBetweenVIEAndEntityOperatingIncomeOrLoss

0

USD

CY2020Q4

us-gaap

Variable Interest Entity Activity Between Vie And Entity Operating Income Or Loss

VariableInterestEntityActivityBetweenVIEAndEntityOperatingIncomeOrLoss

3000000

USD

CY2019Q1

us-gaap

Variable Interest Entity Activity Between Vie And Entity Operating Income Or Loss

VariableInterestEntityActivityBetweenVIEAndEntityOperatingIncomeOrLoss

16000000

USD

CY2019Q2

us-gaap

Variable Interest Entity Activity Between Vie And Entity Operating Income Or Loss

VariableInterestEntityActivityBetweenVIEAndEntityOperatingIncomeOrLoss

3000000

USD

CY2019Q3

us-gaap

Variable Interest Entity Activity Between Vie And Entity Operating Income Or Loss

VariableInterestEntityActivityBetweenVIEAndEntityOperatingIncomeOrLoss

11000000

USD

CY2019Q4

us-gaap

Variable Interest Entity Activity Between Vie And Entity Operating Income Or Loss

VariableInterestEntityActivityBetweenVIEAndEntityOperatingIncomeOrLoss

7000000

USD

CY2020Q1

us-gaap

Incurred Claims Financial Guarantee Insurance Contracts

IncurredClaimsFinancialGuaranteeInsuranceContracts

117000000

USD

CY2020Q2

us-gaap

Incurred Claims Financial Guarantee Insurance Contracts

IncurredClaimsFinancialGuaranteeInsuranceContracts

16000000

USD

CY2020Q3

us-gaap

Incurred Claims Financial Guarantee Insurance Contracts

IncurredClaimsFinancialGuaranteeInsuranceContracts

83000000

USD

CY2020Q4

us-gaap

Incurred Claims Financial Guarantee Insurance Contracts

IncurredClaimsFinancialGuaranteeInsuranceContracts

9000000

USD

CY2019Q1

us-gaap

Incurred Claims Financial Guarantee Insurance Contracts

IncurredClaimsFinancialGuaranteeInsuranceContracts

-12000000

USD

CY2019Q2

us-gaap

Incurred Claims Financial Guarantee Insurance Contracts

IncurredClaimsFinancialGuaranteeInsuranceContracts

-133000000

USD

CY2019Q3

us-gaap

Incurred Claims Financial Guarantee Insurance Contracts

IncurredClaimsFinancialGuaranteeInsuranceContracts

37000000

USD

CY2019Q4

us-gaap

Incurred Claims Financial Guarantee Insurance Contracts

IncurredClaimsFinancialGuaranteeInsuranceContracts

97000000

USD

CY2020Q1

us-gaap

Amortization Of Intangible Assets

AmortizationOfIntangibleAssets

13000000

USD

CY2020Q2

us-gaap

Amortization Of Intangible Assets

AmortizationOfIntangibleAssets

14000000

USD

CY2020Q3

us-gaap

Amortization Of Intangible Assets

AmortizationOfIntangibleAssets

14000000

USD

CY2020Q4

us-gaap

Amortization Of Intangible Assets

AmortizationOfIntangibleAssets

16000000

USD

CY2019Q1

us-gaap

Amortization Of Intangible Assets

AmortizationOfIntangibleAssets

36000000

USD

CY2019Q2

us-gaap

Amortization Of Intangible Assets

AmortizationOfIntangibleAssets

226000000

USD

CY2019Q3

us-gaap

Amortization Of Intangible Assets

AmortizationOfIntangibleAssets

17000000

USD

CY2019Q4

us-gaap

Amortization Of Intangible Assets

AmortizationOfIntangibleAssets

15000000

USD

CY2020Q1

us-gaap

Other Underwriting Expense

OtherUnderwritingExpense

24000000

USD

CY2020Q2

us-gaap

Other Underwriting Expense

OtherUnderwritingExpense

21000000

USD

CY2020Q3

us-gaap

Other Underwriting Expense

OtherUnderwritingExpense

23000000

USD

CY2020Q4

us-gaap

Other Underwriting Expense

OtherUnderwritingExpense

26000000

USD

CY2019Q1

us-gaap

Other Underwriting Expense

OtherUnderwritingExpense

25000000

USD

CY2019Q2

us-gaap

Other Underwriting Expense

OtherUnderwritingExpense

29000000

USD

CY2019Q3

us-gaap

Other Underwriting Expense

OtherUnderwritingExpense

26000000

USD

CY2019Q4

us-gaap

Other Underwriting Expense

OtherUnderwritingExpense

23000000

USD

CY2020Q1

us-gaap

Interest Expense Debt

InterestExpenseDebt

63000000

USD

CY2020Q2

us-gaap

Interest Expense Debt

InterestExpenseDebt

58000000

USD

CY2020Q3

us-gaap

Interest Expense Debt

InterestExpenseDebt

50000000

USD

CY2020Q4

us-gaap

Interest Expense Debt

InterestExpenseDebt

50000000

USD

CY2019Q1

us-gaap

Interest Expense Debt

InterestExpenseDebt

68000000

USD

CY2019Q2

us-gaap

Interest Expense Debt

InterestExpenseDebt

67000000

USD

CY2019Q3

us-gaap

Interest Expense Debt

InterestExpenseDebt

67000000

USD

CY2019Q4

us-gaap

Interest Expense Debt

InterestExpenseDebt

66000000

USD

CY2020Q1

us-gaap

Income Loss From Continuing Operations Before Income Taxes Minority Interest And Income Loss From Equity Method Investments

IncomeLossFromContinuingOperationsBeforeIncomeTaxesMinorityInterestAndIncomeLossFromEquityMethodInvestments

-287000000

USD

CY2020Q4

us-gaap

Income Loss From Continuing Operations Before Income Taxes Minority Interest And Income Loss From Equity Method Investments

IncomeLossFromContinuingOperationsBeforeIncomeTaxesMinorityInterestAndIncomeLossFromEquityMethodInvestments

-12000000

USD

CY2019Q1

us-gaap

Income Loss From Continuing Operations Before Income Taxes Minority Interest And Income Loss From Equity Method Investments

IncomeLossFromContinuingOperationsBeforeIncomeTaxesMinorityInterestAndIncomeLossFromEquityMethodInvestments

-41000000

USD

CY2019Q2

us-gaap

Income Loss From Continuing Operations Before Income Taxes Minority Interest And Income Loss From Equity Method Investments

IncomeLossFromContinuingOperationsBeforeIncomeTaxesMinorityInterestAndIncomeLossFromEquityMethodInvestments

-100000000

USD

CY2019Q3

us-gaap

Income Loss From Continuing Operations Before Income Taxes Minority Interest And Income Loss From Equity Method Investments

IncomeLossFromContinuingOperationsBeforeIncomeTaxesMinorityInterestAndIncomeLossFromEquityMethodInvestments

69000000

USD

CY2019Q4

us-gaap

Income Loss From Continuing Operations Before Income Taxes Minority Interest And Income Loss From Equity Method Investments

IncomeLossFromContinuingOperationsBeforeIncomeTaxesMinorityInterestAndIncomeLossFromEquityMethodInvestments

-111000000

USD

CY2020Q1

us-gaap

Net Income Loss

NetIncomeLoss

-280000000

USD

CY2020Q2

us-gaap

Net Income Loss

NetIncomeLoss

-35000000

USD

CY2020Q3

us-gaap

Net Income Loss

NetIncomeLoss

-108000000

USD

CY2020Q4

us-gaap

Net Income Loss

NetIncomeLoss

-14000000

USD

CY2019Q1

us-gaap

Net Income Loss

NetIncomeLoss

-43000000

USD

CY2019Q2

us-gaap

Net Income Loss

NetIncomeLoss

-128000000

USD

CY2019Q3

us-gaap

Net Income Loss

NetIncomeLoss

66000000

USD

CY2019Q4

us-gaap

Net Income Loss

NetIncomeLoss

-110000000

USD

CY2020Q1

us-gaap

Earnings Per Share Basic

EarningsPerShareBasic

-6.07

CY2020Q2

us-gaap

Earnings Per Share Basic

EarningsPerShareBasic

-0.77

CY2020Q3

us-gaap

Earnings Per Share Basic

EarningsPerShareBasic

-2.33

CY2020Q4

us-gaap

Earnings Per Share Basic

EarningsPerShareBasic

-0.31

CY2019Q1

us-gaap

Earnings Per Share Basic

EarningsPerShareBasic

-0.94

CY2019Q2

us-gaap

Earnings Per Share Basic

EarningsPerShareBasic

-2.79

CY2019Q3

us-gaap

Earnings Per Share Basic

EarningsPerShareBasic

1.44

CY2019Q4

us-gaap

Earnings Per Share Basic

EarningsPerShareBasic

-2.40

CY2020Q1

us-gaap

Earnings Per Share Diluted

EarningsPerShareDiluted

-6.07

CY2020Q2

us-gaap

Earnings Per Share Diluted

EarningsPerShareDiluted

-0.77

CY2020Q3

us-gaap

Earnings Per Share Diluted

EarningsPerShareDiluted

-2.33

CY2020Q4

us-gaap

Earnings Per Share Diluted

EarningsPerShareDiluted

-0.31

CY2019Q1

us-gaap

Earnings Per Share Diluted

EarningsPerShareDiluted

-0.94

CY2019Q2

us-gaap

Earnings Per Share Diluted

EarningsPerShareDiluted

-2.79

CY2019Q3

us-gaap

Earnings Per Share Diluted

EarningsPerShareDiluted

1.41

CY2019Q4

us-gaap

Earnings Per Share Diluted

EarningsPerShareDiluted

-2.40

CY2020Q4

us-gaap

Summary Of Investments Other Than Investments In Related Parties Cost

SummaryOfInvestmentsOtherThanInvestmentsInRelatedPartiesCost

2847000000

USD

CY2020Q4

ambc

Investment Excluding Related Party Investments

InvestmentExcludingRelatedPartyInvestments

3028000000

USD

CY2020Q4

us-gaap

Preferred Stock Par Or Stated Value Per Share

PreferredStockParOrStatedValuePerShare

0.01

CY2019Q4

us-gaap

Preferred Stock Par Or Stated Value Per Share

PreferredStockParOrStatedValuePerShare

0.01

CY2020Q4

us-gaap

Preferred Stock Shares Authorized

PreferredStockSharesAuthorized

20000000

shares

CY2019Q4

us-gaap

Preferred Stock Shares Authorized

PreferredStockSharesAuthorized

20000000

shares

CY2020Q4

us-gaap

Preferred Stock Shares Outstanding

PreferredStockSharesOutstanding

0

shares

CY2019Q4

us-gaap

Common Stock Par Or Stated Value Per Share

CommonStockParOrStatedValuePerShare

0.01

CY2020Q4

us-gaap

Common Stock Par Or Stated Value Per Share

CommonStockParOrStatedValuePerShare

0.01

CY2019Q4

us-gaap

Common Stock Shares Authorized

CommonStockSharesAuthorized

130000000

shares

CY2020Q4

us-gaap

Common Stock Shares Authorized

CommonStockSharesAuthorized

130000000

shares

CY2020Q4

us-gaap

Common Stock Shares Issued

CommonStockSharesIssued

45865081

shares

CY2019Q4

us-gaap

Common Stock Shares Issued

CommonStockSharesIssued

45571743

shares

CY2020Q4

us-gaap

Treasury Stock Shares

TreasuryStockShares

55942

shares

CY2019Q4

us-gaap

Treasury Stock Shares

TreasuryStockShares

16343

shares

CY2019Q4

ambc

Tolling Payment Receivablefrom Aac

TollingPaymentReceivablefromAAC

28000000

USD

CY2020

ambc

Capital Contribution To Subsidiaries

CapitalContributionToSubsidiaries

-29000000

USD

CY1991Q2

dei

Entity Incorporation Date Of Incorporation

EntityIncorporationDateOfIncorporation

1991-04-29

CY2020Q4

us-gaap

Business Acquisition Percentage Of Voting Interests Acquired

BusinessAcquisitionPercentageOfVotingInterestsAcquired

0.80

CY2020

us-gaap

Business Combination Consideration Transferred1

BusinessCombinationConsiderationTransferred1

81000000

USD

CY2020Q4

ambc

Business Combination Redeemable Noncontrolling Percentage

BusinessCombinationRedeemableNoncontrollingPercentage

0.20

CY2020Q4

us-gaap

Operating Loss Carryforwards

OperatingLossCarryforwards

3639000000

USD

CY2011Q3

us-gaap

Operating Loss Carryforwards

OperatingLossCarryforwards

3440000000

USD

CY2020

ambc

Amount Of Nol Reallocated From Aac To Afg

AmountOfNOLReallocatedFromAACToAFG

210000000

USD

CY2020

ambc

Tolling Payments Paid By Aac To Afg

TollingPaymentsPaidByAACToAFG

28000000

USD

CY2020

us-gaap

Direct Premiums Written

DirectPremiumsWritten

-1000000

USD

CY2020

us-gaap

Ceded Premiums Written

CededPremiumsWritten

-1000000

USD

CY2020

us-gaap

Assumed Premiums Written

AssumedPremiumsWritten

0

USD

CY2020

us-gaap

Premiums Written Net

PremiumsWrittenNet

0

USD

CY2020

ambc

Ambc Premiums Written Financial Guarantee Insurance Contracts Percentage Of Amount Assumed To Net

Ambc_PremiumsWrittenFinancialGuaranteeInsuranceContractsPercentageOfAmountAssumedToNet

0

Rate

CY2019

us-gaap

Direct Premiums Written

DirectPremiumsWritten

-28000000

USD

CY2019

us-gaap

Ceded Premiums Written

CededPremiumsWritten

31000000

USD

CY2019

us-gaap

Assumed Premiums Written

AssumedPremiumsWritten

0

USD

CY2019

us-gaap

Premiums Written Net

PremiumsWrittenNet

-60000000

USD

CY2019

ambc

Ambc Premiums Written Financial Guarantee Insurance Contracts Percentage Of Amount Assumed To Net

Ambc_PremiumsWrittenFinancialGuaranteeInsuranceContractsPercentageOfAmountAssumedToNet

0

Rate

CY2018

us-gaap

Direct Premiums Written

DirectPremiumsWritten

-24000000

USD

CY2018

us-gaap

Ceded Premiums Written

CededPremiumsWritten

17000000

USD

CY2018

us-gaap

Assumed Premiums Written

AssumedPremiumsWritten

0

USD

CY2018

us-gaap

Premiums Written Net

PremiumsWrittenNet

-41000000

USD

CY2018

ambc

Ambc Premiums Written Financial Guarantee Insurance Contracts Percentage Of Amount Assumed To Net

Ambc_PremiumsWrittenFinancialGuaranteeInsuranceContractsPercentageOfAmountAssumedToNet

0

Rate

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$AMBC
AMBAC FINANCIAL GROUP INC Stock $ambc

2020 Q4 Form 10-K Financial Statement

#000087450121000028 Filed on March 01, 2021

Income Statement

Balance Sheet

Cashflow Statement

Facts In Submission

Files In Submission

$AMBC AMBAC FINANCIAL GROUP INC Stock $ambc

2020 Q4 Form 10-K Financial Statement

#000087450121000028 Filed on March 01, 2021

Income Statement

Balance Sheet

Cashflow Statement

Facts In Submission

Files In Submission

$AMBC
AMBAC FINANCIAL GROUP INC Stock $ambc