$AGO
ASSURED GUARANTY LTD Stock $ago

$ago Overview Financials Valuation SEC Filings Company Website

2019 Q4 Form 10-Q Financial Statement

#000127381319000050 Filed on November 08, 2019

Income Statement

Concept	2019 Q4	2019 Q3	2019 Q2
Revenue	$82.00M	$206.0M	$266.0M
YoY Change	-16.33%	-25.09%	20.91%
Cost Of Revenue	$18.00M	$30.00M	-$1.000M
YoY Change	-14.29%	76.47%	-102.27%
Gross Profit	$64.00M	$176.0M	$267.0M
YoY Change	-16.88%	-31.78%	51.7%
Gross Profit Margin	78.05%	85.44%	100.38%
Selling, General & Admin	$178.0M
YoY Change
% of Gross Profit	278.13%
Research & Development
YoY Change
% of Gross Profit
Depreciation & Amortization	$5.000M	$3.000M	$4.000M
YoY Change	25.0%	0.0%	0.0%
% of Gross Profit	7.81%	1.7%	1.5%
Operating Expenses	$115.0M	$98.00M	$63.00M
YoY Change	27.78%	28.95%	-42.73%
Operating Profit	-$51.00M	$78.00M	$204.0M
YoY Change	292.31%	-57.14%	209.09%
Interest Expense	$22.00M	$22.00M	$22.00M
YoY Change	-4.35%	-4.35%	-8.33%
% of Operating Profit		28.21%	10.78%
Other Income/Expense, Net
YoY Change
Pretax Income	$138.0M	$86.00M	$182.0M
YoY Change	36.63%	-50.86%	109.2%
Income Tax	$2.000M	$17.00M	$40.00M
% Of Pretax Income	1.45%	19.77%	21.98%
Net Earnings	$137.0M	$69.00M	$142.0M
YoY Change	55.68%	-57.14%	89.33%
Net Earnings / Revenue	167.07%	33.5%	53.38%
Basic Earnings Per Share	$1.43	$0.71	$1.40
Diluted Earnings Per Share	$1.42	$0.70	$1.39
COMMON SHARES
Basic Shares Outstanding	95.39M shares	98.20M shares	101.2M shares
Diluted Shares Outstanding		98.90M shares	101.9M shares

Balance Sheet

Concept	2019 Q4	2019 Q3	2019 Q2
SHORT-TERM ASSETS
Cash & Short-Term Investments
YoY Change
Cash & Equivalents	$183.0M	$229.0M	$194.0M
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	$100.0M	$65.00M	$66.00M
YoY Change
Goodwill	$117.0M
YoY Change
Intangibles
YoY Change
Long-Term Investments	$10.81B	$10.48B	$10.79B
YoY Change	-0.56%	-4.98%	-3.96%
Other Assets
YoY Change
Total Long-Term Assets
YoY Change
TOTAL ASSETS
Total Short-Term Assets
Total Long-Term Assets
Total Assets	$14.33B	$13.37B	$13.58B
YoY Change	5.32%	-2.71%	-3.9%
SHORT-TERM LIABILITIES
YoY Change
Accounts Payable
YoY Change
Accrued Expenses	$130.0M	$90.00M	$91.00M
YoY Change
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	$130.0M	$90.00M	$91.00M
YoY Change
LONG-TERM LIABILITIES
Long-Term Debt	$1.235B	$1.234B	$1.233B
YoY Change	0.16%	-1.2%	-2.45%
Other Long-Term Liabilities	$1.523B	$1.050B	$1.046B
YoY Change	35.26%	-14.08%	-17.77%
Total Long-Term Liabilities	$2.758B	$2.284B	$2.279B
YoY Change	16.91%	-7.57%	-10.13%
TOTAL LIABILITIES
Total Short-Term Liabilities	$130.0M	$90.00M	$91.00M
Total Long-Term Liabilities	$2.758B	$2.284B	$2.279B
Total Liabilities	$7.674B	$6.715B	$6.859B
YoY Change	8.88%	-6.16%	-8.52%
SHAREHOLDERS EQUITY
Retained Earnings	$6.295B	$6.331B	$6.425B
YoY Change	-1.24%	0.44%	4.32%
Common Stock	$1.000M	$1.000M	$1.000M
YoY Change	-98.85%	-99.5%	-99.69%
Preferred Stock
YoY Change
Treasury Stock (at cost)
YoY Change
Treasury Stock Shares
Shareholders Equity	$6.639B	$6.652B	$6.722B
YoY Change
Total Liabilities & Shareholders Equity	$14.33B	$13.37B	$13.58B
YoY Change	5.32%	-2.71%	-3.9%

Cashflow Statement

Concept	2019 Q4	2019 Q3	2019 Q2
OPERATING ACTIVITIES
Net Income	$137.0M	$69.00M	$142.0M
YoY Change	55.68%	-57.14%	89.33%
Depreciation, Depletion And Amortization	$5.000M	$3.000M	$4.000M
YoY Change	25.0%	0.0%	0.0%
Cash From Operating Activities	-$144.0M	-$167.0M	$134.0M
YoY Change	-230.91%	81.52%	-67.87%
INVESTING ACTIVITIES
Capital Expenditures
YoY Change
Acquisitions
YoY Change
Other Investing Activities	$99.00M	$439.0M	$139.0M
YoY Change	-3.88%	111.06%	-199.29%
Cash From Investing Activities	$99.00M	$439.0M	$139.0M
YoY Change	-3.88%	111.06%	-199.29%
FINANCING ACTIVITIES
Cash Dividend Paid
YoY Change
Common Stock Issuance & Retirement, Net
YoY Change
Debt Paid & Issued, Net
YoY Change
Cash From Financing Activities	-6.000M	-235.0M	-201.0M
YoY Change	-96.83%	5.86%	-0.99%
NET CHANGE
Cash From Operating Activities	-144.0M	-167.0M	134.0M
Cash From Investing Activities	99.00M	439.0M	139.0M
Cash From Financing Activities	-6.000M	-235.0M	-201.0M
Net Change In Cash	-51.00M	37.00M	72.00M
YoY Change	-312.5%	-134.91%	-2.7%
FREE CASH FLOW
Cash From Operating Activities	-$144.0M	-$167.0M	$134.0M
Capital Expenditures
Free Cash Flow
YoY Change

Facts In Submission

Frame	Concept Type	Concept / XBRL Key	Value	Unit
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CY2019Q3	ago	Other Comprehensive Income Unrealized Holding Gain Loss On Securities Arising During Period Excluding Other Than Temporary Impairment Losses Tax OtherComprehensiveIncomeUnrealizedHoldingGainLossOnSecuritiesArisingDuringPeriodExcludingOtherThanTemporaryImpairmentLossesTax	7000000	USD
	ago	Other Comprehensive Income Unrealized Holding Gain Loss On Securities Arising During Period Excluding Other Than Temporary Impairment Losses Tax OtherComprehensiveIncomeUnrealizedHoldingGainLossOnSecuritiesArisingDuringPeriodExcludingOtherThanTemporaryImpairmentLossesTax	51000000	USD
	dei	Amendment Flag AmendmentFlag	false
	dei	Current Fiscal Year End Date CurrentFiscalYearEndDate	--12-31
	dei	Entity Central Index Key EntityCentralIndexKey	0001273813
	dei	Entity Current Reporting Status EntityCurrentReportingStatus	Yes
	dei	Entity Filer Category EntityFilerCategory	Large Accelerated Filer
	dei	Document Fiscal Period Focus DocumentFiscalPeriodFocus	Q3
	dei	Document Fiscal Year Focus DocumentFiscalYearFocus	2019
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CY2019Q3	us-gaap	Aoci Tax Attributable To Parent AociTaxAttributableToParent	77000000	USD
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CY2018Q3	us-gaap	Common Stock Dividends Per Share Declared CommonStockDividendsPerShareDeclared	0.16
	us-gaap	Common Stock Dividends Per Share Declared CommonStockDividendsPerShareDeclared	0.48
CY2019Q3	us-gaap	Common Stock Dividends Per Share Declared CommonStockDividendsPerShareDeclared	0.18
	us-gaap	Common Stock Dividends Per Share Declared CommonStockDividendsPerShareDeclared	0.54
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	dei	Document Type DocumentType	10-Q
	dei	Document Quarterly Report DocumentQuarterlyReport	true
	dei	Document Period End Date DocumentPeriodEndDate	2019-09-30
	dei	Document Transition Report DocumentTransitionReport	false
	dei	Entity File Number EntityFileNumber	001-32141
	dei	Entity Registrant Name EntityRegistrantName	ASSURED GUARANTY LTD
	dei	Entity Incorporation State Country Code EntityIncorporationStateCountryCode	D0
	dei	Entity Tax Identification Number EntityTaxIdentificationNumber	98-0429991
	dei	Entity Address Address Line1 EntityAddressAddressLine1	30 Woodbourne Avenue
	dei	Entity Address City Or Town EntityAddressCityOrTown	Hamilton
	dei	Entity Address Postal Zip Code EntityAddressPostalZipCode	HM 08
	dei	Entity Address Country EntityAddressCountry	BM
	dei	City Area Code CityAreaCode	441
	dei	Local Phone Number LocalPhoneNumber	279-5700
	dei	Security12b Title Security12bTitle	Common Shares
	dei	Entity Interactive Data Current EntityInteractiveDataCurrent	Yes
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	dei	Trading Symbol TradingSymbol	AGO
	dei	Security Exchange Name SecurityExchangeName	NYSE
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	us-gaap	Income Tax Expense Benefit IncomeTaxExpenseBenefit	46000000	USD
CY2019Q3	us-gaap	Net Income Loss NetIncomeLoss	69000000	USD
CY2018Q3	us-gaap	Net Income Loss NetIncomeLoss	161000000	USD
	us-gaap	Net Income Loss NetIncomeLoss	265000000	USD
	us-gaap	Net Income Loss NetIncomeLoss	433000000	USD
CY2019Q3	us-gaap	Earnings Per Share Basic EarningsPerShareBasic	0.71
CY2018Q3	us-gaap	Earnings Per Share Basic EarningsPerShareBasic	1.48
	us-gaap	Earnings Per Share Basic EarningsPerShareBasic	2.63
	us-gaap	Earnings Per Share Basic EarningsPerShareBasic	3.87
CY2019Q3	us-gaap	Earnings Per Share Diluted EarningsPerShareDiluted	0.70
CY2018Q3	us-gaap	Earnings Per Share Diluted EarningsPerShareDiluted	1.47
	us-gaap	Earnings Per Share Diluted EarningsPerShareDiluted	2.61
	us-gaap	Earnings Per Share Diluted EarningsPerShareDiluted	3.83
CY2019Q3	us-gaap	Net Income Loss NetIncomeLoss	69000000	USD
CY2018Q3	us-gaap	Net Income Loss NetIncomeLoss	161000000	USD
	us-gaap	Net Income Loss NetIncomeLoss	265000000	USD
	us-gaap	Net Income Loss NetIncomeLoss	433000000	USD
CY2019Q3	ago	Other Comprehensive Income Unrealized Holding Gain Loss On Securities With No Other Than Temporary Impairment Arising During Period Net Of Tax OtherComprehensiveIncomeUnrealizedHoldingGainLossOnSecuritiesWithNoOtherThanTemporaryImpairmentArisingDuringPeriodNetOfTax	33000000	USD
CY2018Q3	ago	Other Comprehensive Income Unrealized Holding Gain Loss On Securities With No Other Than Temporary Impairment Arising During Period Net Of Tax OtherComprehensiveIncomeUnrealizedHoldingGainLossOnSecuritiesWithNoOtherThanTemporaryImpairmentArisingDuringPeriodNetOfTax	-59000000	USD
	ago	Other Comprehensive Income Unrealized Holding Gain Loss On Securities With No Other Than Temporary Impairment Arising During Period Net Of Tax OtherComprehensiveIncomeUnrealizedHoldingGainLossOnSecuritiesWithNoOtherThanTemporaryImpairmentArisingDuringPeriodNetOfTax	275000000	USD
	ago	Other Comprehensive Income Unrealized Holding Gain Loss On Securities With No Other Than Temporary Impairment Arising During Period Net Of Tax OtherComprehensiveIncomeUnrealizedHoldingGainLossOnSecuritiesWithNoOtherThanTemporaryImpairmentArisingDuringPeriodNetOfTax	-250000000	USD
CY2019Q3	us-gaap	Other Than Temporary Impairment Losses Investments Portion In Other Comprehensive Income Loss Net Of Tax Portion Attributable To Parent Availableforsale Securities OtherThanTemporaryImpairmentLossesInvestmentsPortionInOtherComprehensiveIncomeLossNetOfTaxPortionAttributableToParentAvailableforsaleSecurities	9000000	USD
CY2018Q3	us-gaap	Other Than Temporary Impairment Losses Investments Portion In Other Comprehensive Income Loss Net Of Tax Portion Attributable To Parent Availableforsale Securities OtherThanTemporaryImpairmentLossesInvestmentsPortionInOtherComprehensiveIncomeLossNetOfTaxPortionAttributableToParentAvailableforsaleSecurities	9000000	USD
	us-gaap	Other Than Temporary Impairment Losses Investments Portion In Other Comprehensive Income Loss Net Of Tax Portion Attributable To Parent Availableforsale Securities OtherThanTemporaryImpairmentLossesInvestmentsPortionInOtherComprehensiveIncomeLossNetOfTaxPortionAttributableToParentAvailableforsaleSecurities	52000000	USD
	us-gaap	Other Than Temporary Impairment Losses Investments Portion In Other Comprehensive Income Loss Net Of Tax Portion Attributable To Parent Availableforsale Securities OtherThanTemporaryImpairmentLossesInvestmentsPortionInOtherComprehensiveIncomeLossNetOfTaxPortionAttributableToParentAvailableforsaleSecurities	5000000	USD
CY2019Q3	us-gaap	Other Comprehensive Income Unrealized Holding Gain Loss On Securities Arising During Period Net Of Tax OtherComprehensiveIncomeUnrealizedHoldingGainLossOnSecuritiesArisingDuringPeriodNetOfTax	24000000	USD
CY2018Q3	us-gaap	Other Comprehensive Income Unrealized Holding Gain Loss On Securities Arising During Period Net Of Tax OtherComprehensiveIncomeUnrealizedHoldingGainLossOnSecuritiesArisingDuringPeriodNetOfTax	-68000000	USD
	us-gaap	Other Comprehensive Income Unrealized Holding Gain Loss On Securities Arising During Period Net Of Tax OtherComprehensiveIncomeUnrealizedHoldingGainLossOnSecuritiesArisingDuringPeriodNetOfTax	223000000	USD
	us-gaap	Other Comprehensive Income Unrealized Holding Gain Loss On Securities Arising During Period Net Of Tax OtherComprehensiveIncomeUnrealizedHoldingGainLossOnSecuritiesArisingDuringPeriodNetOfTax	-255000000	USD
CY2019Q3	us-gaap	Other Comprehensive Income Loss Financial Liability Fair Value Option After Tax And Reclassification Adjustment OtherComprehensiveIncomeLossFinancialLiabilityFairValueOptionAfterTaxAndReclassificationAdjustment	0	USD
	us-gaap	Stock Repurchased And Retired During Period Value StockRepurchasedAndRetiredDuringPeriodValue	380000000	USD
	us-gaap	Other Comprehensive Income Loss Net Of Tax Portion Attributable To Parent OtherComprehensiveIncomeLossNetOfTaxPortionAttributableToParent	-262000000	USD
CY2018Q3	us-gaap	Other Comprehensive Income Loss Financial Liability Fair Value Option After Tax And Reclassification Adjustment OtherComprehensiveIncomeLossFinancialLiabilityFairValueOptionAfterTaxAndReclassificationAdjustment	-3000000	USD
	us-gaap	Other Comprehensive Income Loss Financial Liability Fair Value Option After Tax And Reclassification Adjustment OtherComprehensiveIncomeLossFinancialLiabilityFairValueOptionAfterTaxAndReclassificationAdjustment	4000000	USD
	us-gaap	Other Comprehensive Income Loss Financial Liability Fair Value Option After Tax And Reclassification Adjustment OtherComprehensiveIncomeLossFinancialLiabilityFairValueOptionAfterTaxAndReclassificationAdjustment	-1000000	USD
CY2019Q3	ago	Other Comprehensive Income Loss Other Netof Tax Portion Attributable To Parent OtherComprehensiveIncomeLossOtherNetofTaxPortionAttributableToParent	0	USD
CY2018Q3	ago	Other Comprehensive Income Loss Other Netof Tax Portion Attributable To Parent OtherComprehensiveIncomeLossOtherNetofTaxPortionAttributableToParent	-3000000	USD
	ago	Other Comprehensive Income Loss Other Netof Tax Portion Attributable To Parent OtherComprehensiveIncomeLossOtherNetofTaxPortionAttributableToParent	-1000000	USD
	ago	Other Comprehensive Income Loss Other Netof Tax Portion Attributable To Parent OtherComprehensiveIncomeLossOtherNetofTaxPortionAttributableToParent	-6000000	USD
CY2019Q3	us-gaap	Other Comprehensive Income Loss Net Of Tax Portion Attributable To Parent OtherComprehensiveIncomeLossNetOfTaxPortionAttributableToParent	24000000	USD
CY2018Q3	us-gaap	Other Comprehensive Income Loss Net Of Tax Portion Attributable To Parent OtherComprehensiveIncomeLossNetOfTaxPortionAttributableToParent	-74000000	USD
	us-gaap	Other Comprehensive Income Loss Net Of Tax Portion Attributable To Parent OtherComprehensiveIncomeLossNetOfTaxPortionAttributableToParent	226000000	USD
	us-gaap	Other Comprehensive Income Loss Net Of Tax Portion Attributable To Parent OtherComprehensiveIncomeLossNetOfTaxPortionAttributableToParent	-262000000	USD
CY2019Q3	us-gaap	Comprehensive Income Net Of Tax Including Portion Attributable To Noncontrolling Interest ComprehensiveIncomeNetOfTaxIncludingPortionAttributableToNoncontrollingInterest	93000000	USD
CY2018Q3	us-gaap	Comprehensive Income Net Of Tax Including Portion Attributable To Noncontrolling Interest ComprehensiveIncomeNetOfTaxIncludingPortionAttributableToNoncontrollingInterest	87000000	USD
	us-gaap	Comprehensive Income Net Of Tax Including Portion Attributable To Noncontrolling Interest ComprehensiveIncomeNetOfTaxIncludingPortionAttributableToNoncontrollingInterest	491000000	USD
	us-gaap	Comprehensive Income Net Of Tax Including Portion Attributable To Noncontrolling Interest ComprehensiveIncomeNetOfTaxIncludingPortionAttributableToNoncontrollingInterest	171000000	USD
CY2019Q2	us-gaap	Stockholders Equity StockholdersEquity	6722000000	USD
CY2019Q3	us-gaap	Net Income Loss NetIncomeLoss	69000000	USD
CY2019Q3	us-gaap	Dividends Common Stock Cash DividendsCommonStockCash	18000000	USD
CY2019Q3	ago	Stock Issued During Period Value Sharebased Compensationand Other StockIssuedDuringPeriodValueSharebasedCompensationandOther	5000000	USD
CY2019Q3	us-gaap	Stock Repurchased And Retired During Period Value StockRepurchasedAndRetiredDuringPeriodValue	150000000	USD
CY2019Q3	us-gaap	Other Comprehensive Income Loss Net Of Tax Portion Attributable To Parent OtherComprehensiveIncomeLossNetOfTaxPortionAttributableToParent	24000000	USD
CY2019Q3	us-gaap	Stockholders Equity StockholdersEquity	6652000000	USD
CY2018Q2	us-gaap	Stockholders Equity StockholdersEquity	6634000000	USD
CY2018Q3	us-gaap	Net Income Loss NetIncomeLoss	161000000	USD
CY2018Q3	us-gaap	Dividends Common Stock Cash DividendsCommonStockCash	17000000	USD
CY2018Q3	ago	Stock Issued During Period Value Sharebased Compensationand Other StockIssuedDuringPeriodValueSharebasedCompensationandOther	9000000	USD
CY2018Q3	us-gaap	Stock Repurchased And Retired During Period Value StockRepurchasedAndRetiredDuringPeriodValue	130000000	USD
CY2018Q3	us-gaap	Other Comprehensive Income Loss Net Of Tax Portion Attributable To Parent OtherComprehensiveIncomeLossNetOfTaxPortionAttributableToParent	-74000000	USD
CY2018Q3	us-gaap	Stockholders Equity StockholdersEquity	6583000000	USD
CY2018Q4	us-gaap	Stockholders Equity StockholdersEquity	6555000000	USD
	us-gaap	Net Income Loss NetIncomeLoss	265000000	USD
	us-gaap	Dividends Common Stock Cash DividendsCommonStockCash	56000000	USD
	ago	Stock Issued During Period Value Sharebased Compensationand Other StockIssuedDuringPeriodValueSharebasedCompensationandOther	2000000	USD
	us-gaap	Stock Repurchased And Retired During Period Value StockRepurchasedAndRetiredDuringPeriodValue	340000000	USD
	us-gaap	Other Comprehensive Income Loss Net Of Tax Portion Attributable To Parent OtherComprehensiveIncomeLossNetOfTaxPortionAttributableToParent	226000000	USD
CY2019Q3	us-gaap	Stockholders Equity StockholdersEquity	6652000000	USD
CY2017Q4	us-gaap	Stockholders Equity StockholdersEquity	6839000000	USD
	us-gaap	Net Income Loss NetIncomeLoss	433000000	USD
	us-gaap	Dividends Common Stock Cash DividendsCommonStockCash	54000000	USD
	ago	Stock Issued During Period Value Sharebased Compensationand Other StockIssuedDuringPeriodValueSharebasedCompensationandOther	7000000	USD
	us-gaap	Net Cash Provided By Used In Operating Activities NetCashProvidedByUsedInOperatingActivities	352000000	USD
	us-gaap	Payments To Acquire Available For Sale Securities Debt PaymentsToAcquireAvailableForSaleSecuritiesDebt	688000000	USD
CY2018Q3	us-gaap	Stockholders Equity StockholdersEquity	6583000000	USD
	us-gaap	Net Cash Provided By Used In Operating Activities NetCashProvidedByUsedInOperatingActivities	-365000000	USD
	us-gaap	Payments To Acquire Available For Sale Securities Debt PaymentsToAcquireAvailableForSaleSecuritiesDebt	1478000000	USD
	us-gaap	Proceeds From Sale Of Available For Sale Securities Debt ProceedsFromSaleOfAvailableForSaleSecuritiesDebt	1306000000	USD
	us-gaap	Proceeds From Sale Of Available For Sale Securities Debt ProceedsFromSaleOfAvailableForSaleSecuritiesDebt	908000000	USD
	us-gaap	Proceeds From Maturities Prepayments And Calls Of Available For Sale Securities ProceedsFromMaturitiesPrepaymentsAndCallsOfAvailableForSaleSecurities	664000000	USD
	us-gaap	Proceeds From Maturities Prepayments And Calls Of Available For Sale Securities ProceedsFromMaturitiesPrepaymentsAndCallsOfAvailableForSaleSecurities	746000000	USD
	us-gaap	Payments To Acquire Short Term Investments PaymentsToAcquireShortTermInvestments	216000000	USD
	us-gaap	Payments To Acquire Short Term Investments PaymentsToAcquireShortTermInvestments	148000000	USD
	us-gaap	Proceeds From Sale Of Short Term Investments ProceedsFromSaleOfShortTermInvestments	2000000	USD
	us-gaap	Proceeds From Sale Of Short Term Investments ProceedsFromSaleOfShortTermInvestments	1000000	USD
	us-gaap	Proceeds From Maturities Prepayments And Calls Of Shortterm Investments ProceedsFromMaturitiesPrepaymentsAndCallsOfShorttermInvestments	206000000	USD
	us-gaap	Proceeds From Maturities Prepayments And Calls Of Shortterm Investments ProceedsFromMaturitiesPrepaymentsAndCallsOfShorttermInvestments	136000000	USD
	us-gaap	Payments For Proceeds From Short Term Investments PaymentsForProceedsFromShortTermInvestments	404000000	USD
	us-gaap	Payments For Proceeds From Short Term Investments PaymentsForProceedsFromShortTermInvestments	80000000	USD
	ago	Proceedsfrom Paydownson Financial Guaranty Variable Interest Entities Assets ProceedsfromPaydownsonFinancialGuarantyVariableInterestEntitiesAssets	119000000	USD
	ago	Proceedsfrom Paydownson Financial Guaranty Variable Interest Entities Assets ProceedsfromPaydownsonFinancialGuarantyVariableInterestEntitiesAssets	90000000	USD
	ago	Proceedsfrom Saleof Financial Guaranty Variable Interest Entities Assets ProceedsfromSaleofFinancialGuarantyVariableInterestEntitiesAssets	51000000	USD
	ago	Proceedsfrom Saleof Financial Guaranty Variable Interest Entities Assets ProceedsfromSaleofFinancialGuarantyVariableInterestEntitiesAssets	0	USD
	us-gaap	Payments For Proceeds From Other Investing Activities PaymentsForProceedsFromOtherInvestingActivities	-30000000	USD
	us-gaap	Payments For Proceeds From Other Investing Activities PaymentsForProceedsFromOtherInvestingActivities	-19000000	USD
	us-gaap	Net Cash Provided By Used In Investing Activities NetCashProvidedByUsedInInvestingActivities	1070000000	USD
	us-gaap	Net Cash Provided By Used In Investing Activities NetCashProvidedByUsedInInvestingActivities	194000000	USD
	us-gaap	Payments Of Dividends Common Stock PaymentsOfDividendsCommonStock	56000000	USD
	us-gaap	Payments Of Dividends Common Stock PaymentsOfDividendsCommonStock	55000000	USD
	us-gaap	Payments For Repurchase Of Common Stock PaymentsForRepurchaseOfCommonStock	340000000	USD
	us-gaap	Payments For Repurchase Of Common Stock PaymentsForRepurchaseOfCommonStock	380000000	USD
	ago	Paydown Of Financial Guaranty Variable Interest Entities Liabilities PaydownOfFinancialGuarantyVariableInterestEntitiesLiabilities	162000000	USD
	ago	Paydown Of Financial Guaranty Variable Interest Entities Liabilities PaydownOfFinancialGuarantyVariableInterestEntitiesLiabilities	90000000	USD
	us-gaap	Repayments Of Long Term Debt RepaymentsOfLongTermDebt	4000000	USD
	us-gaap	Repayments Of Long Term Debt RepaymentsOfLongTermDebt	73000000	USD
	us-gaap	Proceeds From Payments For Other Financing Activities ProceedsFromPaymentsForOtherFinancingActivities	-16000000	USD
	us-gaap	Proceeds From Payments For Other Financing Activities ProceedsFromPaymentsForOtherFinancingActivities	-8000000	USD
	us-gaap	Net Cash Provided By Used In Financing Activities NetCashProvidedByUsedInFinancingActivities	-578000000	USD
	us-gaap	Net Cash Provided By Used In Financing Activities NetCashProvidedByUsedInFinancingActivities	-606000000	USD
	us-gaap	Effect Of Exchange Rate On Cash And Cash Equivalents EffectOfExchangeRateOnCashAndCashEquivalents	-2000000	USD
	us-gaap	Effect Of Exchange Rate On Cash And Cash Equivalents EffectOfExchangeRateOnCashAndCashEquivalents	-2000000	USD
	us-gaap	Cash Cash Equivalents Restricted Cash And Restricted Cash Equivalents Period Increase Decrease Including Exchange Rate Effect CashCashEquivalentsRestrictedCashAndRestrictedCashEquivalentsPeriodIncreaseDecreaseIncludingExchangeRateEffect	125000000	USD
	us-gaap	Cash Cash Equivalents Restricted Cash And Restricted Cash Equivalents Period Increase Decrease Including Exchange Rate Effect CashCashEquivalentsRestrictedCashAndRestrictedCashEquivalentsPeriodIncreaseDecreaseIncludingExchangeRateEffect	-62000000	USD
CY2018Q4	us-gaap	Cash Cash Equivalents Restricted Cash And Restricted Cash Equivalents CashCashEquivalentsRestrictedCashAndRestrictedCashEquivalents	104000000	USD
CY2017Q4	us-gaap	Cash Cash Equivalents Restricted Cash And Restricted Cash Equivalents CashCashEquivalentsRestrictedCashAndRestrictedCashEquivalents	144000000	USD
CY2019Q3	us-gaap	Cash Cash Equivalents Restricted Cash And Restricted Cash Equivalents CashCashEquivalentsRestrictedCashAndRestrictedCashEquivalents	229000000	USD
CY2018Q3	us-gaap	Cash Cash Equivalents Restricted Cash And Restricted Cash Equivalents CashCashEquivalentsRestrictedCashAndRestrictedCashEquivalents	82000000	USD
	us-gaap	Income Taxes Paid Net IncomeTaxesPaidNet	-2000000	USD
	us-gaap	Income Taxes Paid Net IncomeTaxesPaidNet	-5000000	USD
	us-gaap	Interest Paid Net InterestPaidNet	51000000	USD
	us-gaap	Interest Paid Net InterestPaidNet	66000000	USD
CY2019Q3	ago	Number Of Holding Companies Having Outstanding Public Debt NumberOfHoldingCompaniesHavingOutstandingPublicDebt	2	Company
CY2019Q3	ago	Insured Financial Obligations Outstanding Principal Amount Secondto Pay Amount Net InsuredFinancialObligationsOutstandingPrincipalAmountSecondtoPayAmountNet	6400000000	USD
CY2018Q4	ago	Insured Financial Obligations Outstanding Principal Amount Secondto Pay Amount Net InsuredFinancialObligationsOutstandingPrincipalAmountSecondtoPayAmountNet	6700000000	USD
CY2019Q3	ago	Insured Financial Obligations Loss Mitigation Securities InsuredFinancialObligationsLossMitigationSecurities	1500000000	USD
CY2018Q4	ago	Insured Financial Obligations Loss Mitigation Securities InsuredFinancialObligationsLossMitigationSecurities	1900000000	USD
CY2019Q3	ago	Insured Financial Obligations Insured Contractual Payments Outstanding Gross InsuredFinancialObligationsInsuredContractualPaymentsOutstandingGross	356280000000	USD
CY2018Q4	ago	Insured Financial Obligations Insured Contractual Payments Outstanding Gross InsuredFinancialObligationsInsuredContractualPaymentsOutstandingGross	375080000000	USD
CY2019Q3	ago	Insured Financial Obligations Insured Contractual Payments Outstanding Net InsuredFinancialObligationsInsuredContractualPaymentsOutstandingNet	354612000000	USD
CY2018Q4	ago	Insured Financial Obligations Insured Contractual Payments Outstanding Net InsuredFinancialObligationsInsuredContractualPaymentsOutstandingNet	371586000000	USD
CY2019Q3	ago	Insured Financial Obligations Outstanding Principal Amount Net InsuredFinancialObligationsOutstandingPrincipalAmountNet	229375000000	USD
CY2019Q3	ago	Insured Financial Obligations Outstanding Principle Amount Percentage InsuredFinancialObligationsOutstandingPrincipleAmountPercentage	1.000
CY2018Q4	ago	Insured Financial Obligations Outstanding Principal Amount Net InsuredFinancialObligationsOutstandingPrincipalAmountNet	241802000000	USD
CY2018Q4	ago	Insured Financial Obligations Outstanding Principle Amount Percentage InsuredFinancialObligationsOutstandingPrincipleAmountPercentage	1.000
CY2019Q3	ago	Insured Financial Obligations Outstanding Principal Amount Net InsuredFinancialObligationsOutstandingPrincipalAmountNet	229375000000	USD
CY2018Q4	ago	Insured Financial Obligations Outstanding Principal Amount Net InsuredFinancialObligationsOutstandingPrincipalAmountNet	241802000000	USD
	ago	Insured Financial Obligations Insured Credit Performanceof Guaranteed Obligations Term InsuredFinancialObligationsInsuredCreditPerformanceofGuaranteedObligationsTerm	P30Y
	ago	Insured Financial Obligations Claim Liability Weighted Average Risk Free Discount Rate InsuredFinancialObligationsClaimLiabilityWeightedAverageRiskFreeDiscountRate	0.0179
CY2018	ago	Insured Financial Obligations Claim Liability Weighted Average Risk Free Discount Rate InsuredFinancialObligationsClaimLiabilityWeightedAverageRiskFreeDiscountRate	0.0274
CY2019Q2	ago	Guarantor Obligations Net Expected Losstobe Paid After Recoveriesfor Representationsand Warranties GuarantorObligationsNetExpectedLosstobePaidAfterRecoveriesforRepresentationsandWarranties	960000000	USD
CY2018Q2	ago	Guarantor Obligations Net Expected Losstobe Paid After Recoveriesfor Representationsand Warranties GuarantorObligationsNetExpectedLosstobePaidAfterRecoveriesforRepresentationsandWarranties	1432000000	USD
CY2018Q4	ago	Guarantor Obligations Net Expected Losstobe Paid After Recoveriesfor Representationsand Warranties GuarantorObligationsNetExpectedLosstobePaidAfterRecoveriesforRepresentationsandWarranties	1183000000	USD
CY2017Q4	ago	Guarantor Obligations Net Expected Losstobe Paid After Recoveriesfor Representationsand Warranties GuarantorObligationsNetExpectedLosstobePaidAfterRecoveriesforRepresentationsandWarranties	1303000000	USD
CY2019Q3	ago	Guarantor Obligations Net Expected Loss Development After Recoveriesfor Representationsand Warranties Accretion Of Discount GuarantorObligationsNetExpectedLossDevelopmentAfterRecoveriesforRepresentationsandWarrantiesAccretionOfDiscount	5000000	USD
CY2018Q3	ago	Guarantor Obligations Net Expected Loss Development After Recoveriesfor Representationsand Warranties Accretion Of Discount GuarantorObligationsNetExpectedLossDevelopmentAfterRecoveriesforRepresentationsandWarrantiesAccretionOfDiscount	10000000	USD
	ago	Guarantor Obligations Net Expected Loss Development After Recoveriesfor Representationsand Warranties Accretion Of Discount GuarantorObligationsNetExpectedLossDevelopmentAfterRecoveriesforRepresentationsandWarrantiesAccretionOfDiscount	19000000	USD
	ago	Guarantor Obligations Net Expected Loss Development After Recoveriesfor Representationsand Warranties Accretion Of Discount GuarantorObligationsNetExpectedLossDevelopmentAfterRecoveriesforRepresentationsandWarrantiesAccretionOfDiscount	27000000	USD
CY2019Q3	ago	Guarantor Obligations Net Expected Loss Development After Recoveriesfor Representationsand Warranties Changes In Discount Rates GuarantorObligationsNetExpectedLossDevelopmentAfterRecoveriesforRepresentationsandWarrantiesChangesInDiscountRates	1000000	USD
CY2018Q3	ago	Guarantor Obligations Net Expected Loss Development After Recoveriesfor Representationsand Warranties Changes In Discount Rates GuarantorObligationsNetExpectedLossDevelopmentAfterRecoveriesforRepresentationsandWarrantiesChangesInDiscountRates	-9000000	USD
	ago	Guarantor Obligations Net Expected Loss Development After Recoveriesfor Representationsand Warranties Changes In Discount Rates GuarantorObligationsNetExpectedLossDevelopmentAfterRecoveriesforRepresentationsandWarrantiesChangesInDiscountRates	-4000000	USD
	ago	Guarantor Obligations Net Expected Loss Development After Recoveriesfor Representationsand Warranties Changes In Discount Rates GuarantorObligationsNetExpectedLossDevelopmentAfterRecoveriesforRepresentationsandWarrantiesChangesInDiscountRates	-15000000	USD
CY2019Q3	ago	Guarantor Obligations Net Expected Loss Development After Recoveriesfor Representationsand Warranties Changes In Timing And Assumptions GuarantorObligationsNetExpectedLossDevelopmentAfterRecoveriesforRepresentationsandWarrantiesChangesInTimingAndAssumptions	19000000	USD
CY2018Q3	ago	Guarantor Obligations Net Expected Loss Development After Recoveriesfor Representationsand Warranties Changes In Timing And Assumptions GuarantorObligationsNetExpectedLossDevelopmentAfterRecoveriesforRepresentationsandWarrantiesChangesInTimingAndAssumptions	-1000000	USD
	ago	Guarantor Obligations Net Expected Loss Development After Recoveriesfor Representationsand Warranties Changes In Timing And Assumptions GuarantorObligationsNetExpectedLossDevelopmentAfterRecoveriesforRepresentationsandWarrantiesChangesInTimingAndAssumptions	-29000000	USD
	ago	Guarantor Obligations Net Expected Loss Development After Recoveriesfor Representationsand Warranties Changes In Timing And Assumptions GuarantorObligationsNetExpectedLossDevelopmentAfterRecoveriesforRepresentationsandWarrantiesChangesInTimingAndAssumptions	-17000000	USD
CY2019Q3	ago	Guarantor Obligations Net Expected Loss Development After Recoveriesfor Representationsand Warranties GuarantorObligationsNetExpectedLossDevelopmentAfterRecoveriesforRepresentationsandWarranties	25000000	USD
CY2018Q3	ago	Guarantor Obligations Net Expected Loss Development After Recoveriesfor Representationsand Warranties GuarantorObligationsNetExpectedLossDevelopmentAfterRecoveriesforRepresentationsandWarranties	0	USD
	ago	Guarantor Obligations Net Expected Loss Development After Recoveriesfor Representationsand Warranties GuarantorObligationsNetExpectedLossDevelopmentAfterRecoveriesforRepresentationsandWarranties	-14000000	USD
	ago	Guarantor Obligations Net Expected Loss Development After Recoveriesfor Representationsand Warranties GuarantorObligationsNetExpectedLossDevelopmentAfterRecoveriesforRepresentationsandWarranties	-5000000	USD
CY2019Q3	ago	Guarantor Obligations Liability For Unpaid Claims And Claims Adjustment Expense Claims Paid After Recoveriesfor Representationsand Warranties GuarantorObligationsLiabilityForUnpaidClaimsAndClaimsAdjustmentExpenseClaimsPaidAfterRecoveriesforRepresentationsandWarranties	267000000	USD
CY2018Q3	ago	Guarantor Obligations Liability For Unpaid Claims And Claims Adjustment Expense Claims Paid After Recoveriesfor Representationsand Warranties GuarantorObligationsLiabilityForUnpaidClaimsAndClaimsAdjustmentExpenseClaimsPaidAfterRecoveriesforRepresentationsandWarranties	241000000	USD
	ago	Guarantor Obligations Liability For Unpaid Claims And Claims Adjustment Expense Claims Paid After Recoveriesfor Representationsand Warranties GuarantorObligationsLiabilityForUnpaidClaimsAndClaimsAdjustmentExpenseClaimsPaidAfterRecoveriesforRepresentationsandWarranties	451000000	USD
	ago	Guarantor Obligations Liability For Unpaid Claims And Claims Adjustment Expense Claims Paid After Recoveriesfor Representationsand Warranties GuarantorObligationsLiabilityForUnpaidClaimsAndClaimsAdjustmentExpenseClaimsPaidAfterRecoveriesforRepresentationsandWarranties	238000000	USD
CY2019Q3	ago	Guarantor Obligations Net Expected Losstobe Paid After Recoveriesfor Representationsand Warranties GuarantorObligationsNetExpectedLosstobePaidAfterRecoveriesforRepresentationsandWarranties	718000000	USD
CY2018Q3	ago	Guarantor Obligations Net Expected Losstobe Paid After Recoveriesfor Representationsand Warranties GuarantorObligationsNetExpectedLosstobePaidAfterRecoveriesforRepresentationsandWarranties	1191000000	USD
CY2019Q3	ago	Guarantor Obligations Net Expected Losstobe Paid After Recoveriesfor Representationsand Warranties GuarantorObligationsNetExpectedLosstobePaidAfterRecoveriesforRepresentationsandWarranties	718000000	USD
CY2018Q3	ago	Guarantor Obligations Net Expected Losstobe Paid After Recoveriesfor Representationsand Warranties GuarantorObligationsNetExpectedLosstobePaidAfterRecoveriesforRepresentationsandWarranties	1191000000	USD
CY2019Q2	ago	Guarantor Obligations Net Expected Losstobe Paid After Recoveriesfor Representationsand Warranties GuarantorObligationsNetExpectedLosstobePaidAfterRecoveriesforRepresentationsandWarranties	960000000	USD
CY2019Q3	ago	Guarantor Obligations Net Expected Loss Development After Recoveriesfor Representationsand Warranties GuarantorObligationsNetExpectedLossDevelopmentAfterRecoveriesforRepresentationsandWarranties	25000000	USD
CY2019Q3	ago	Guarantor Obligations Liability For Unpaid Claims And Claims Adjustment Expense Claims Paid After Recoveriesfor Representationsand Warranties GuarantorObligationsLiabilityForUnpaidClaimsAndClaimsAdjustmentExpenseClaimsPaidAfterRecoveriesforRepresentationsandWarranties	267000000	USD
CY2019Q3	ago	Guarantor Obligations Net Expected Losstobe Paid After Recoveriesfor Representationsand Warranties GuarantorObligationsNetExpectedLosstobePaidAfterRecoveriesforRepresentationsandWarranties	718000000	USD
CY2018Q2	ago	Guarantor Obligations Net Expected Losstobe Paid After Recoveriesfor Representationsand Warranties GuarantorObligationsNetExpectedLosstobePaidAfterRecoveriesforRepresentationsandWarranties	1432000000	USD
CY2018Q3	ago	Guarantor Obligations Net Expected Loss Development After Recoveriesfor Representationsand Warranties GuarantorObligationsNetExpectedLossDevelopmentAfterRecoveriesforRepresentationsandWarranties	0	USD
CY2018Q3	ago	Guarantor Obligations Liability For Unpaid Claims And Claims Adjustment Expense Claims Paid After Recoveriesfor Representationsand Warranties GuarantorObligationsLiabilityForUnpaidClaimsAndClaimsAdjustmentExpenseClaimsPaidAfterRecoveriesforRepresentationsandWarranties	241000000	USD
CY2018Q3	ago	Guarantor Obligations Net Expected Losstobe Paid After Recoveriesfor Representationsand Warranties GuarantorObligationsNetExpectedLosstobePaidAfterRecoveriesforRepresentationsandWarranties	1191000000	USD
CY2018Q4	ago	Guarantor Obligations Net Expected Losstobe Paid After Recoveriesfor Representationsand Warranties GuarantorObligationsNetExpectedLosstobePaidAfterRecoveriesforRepresentationsandWarranties	1183000000	USD
	ago	Guarantor Obligations Net Expected Loss Development After Recoveriesfor Representationsand Warranties GuarantorObligationsNetExpectedLossDevelopmentAfterRecoveriesforRepresentationsandWarranties	-14000000	USD
	ago	Guarantor Obligations Liability For Unpaid Claims And Claims Adjustment Expense Claims Paid After Recoveriesfor Representationsand Warranties GuarantorObligationsLiabilityForUnpaidClaimsAndClaimsAdjustmentExpenseClaimsPaidAfterRecoveriesforRepresentationsandWarranties	451000000	USD
CY2019Q3	ago	Guarantor Obligations Net Expected Losstobe Paid After Recoveriesfor Representationsand Warranties GuarantorObligationsNetExpectedLosstobePaidAfterRecoveriesforRepresentationsandWarranties	718000000	USD
CY2017Q4	ago	Guarantor Obligations Net Expected Losstobe Paid After Recoveriesfor Representationsand Warranties GuarantorObligationsNetExpectedLosstobePaidAfterRecoveriesforRepresentationsandWarranties	1303000000	USD
	ago	Guarantor Obligations Net Expected Loss Development After Recoveriesfor Representationsand Warranties GuarantorObligationsNetExpectedLossDevelopmentAfterRecoveriesforRepresentationsandWarranties	-5000000	USD
	ago	Guarantor Obligations Liability For Unpaid Claims And Claims Adjustment Expense Claims Paid After Recoveriesfor Representationsand Warranties GuarantorObligationsLiabilityForUnpaidClaimsAndClaimsAdjustmentExpenseClaimsPaidAfterRecoveriesforRepresentationsandWarranties	238000000	USD
CY2018Q3	ago	Guarantor Obligations Net Expected Losstobe Paid After Recoveriesfor Representationsand Warranties GuarantorObligationsNetExpectedLosstobePaidAfterRecoveriesforRepresentationsandWarranties	1191000000	USD
	ago	Reinsurance Recoverables Periodafter Endof Reporting Periodfor Settlementof Ceded Paid Losses ReinsuranceRecoverablesPeriodafterEndofReportingPeriodforSettlementofCededPaidLosses	P45D
CY2019Q3	ago	Insured Financial Obligations Liabilityfor Unpaid Claims Adjustment Expense Claims Paid InsuredFinancialObligationsLiabilityforUnpaidClaimsAdjustmentExpenseClaimsPaid	7000000	USD
CY2018Q3	ago	Insured Financial Obligations Liabilityfor Unpaid Claims Adjustment Expense Claims Paid InsuredFinancialObligationsLiabilityforUnpaidClaimsAdjustmentExpenseClaimsPaid	6000000	USD
	ago	Insured Financial Obligations Liabilityfor Unpaid Claims Adjustment Expense Claims Paid InsuredFinancialObligationsLiabilityforUnpaidClaimsAdjustmentExpenseClaimsPaid	23000000	USD
	ago	Insured Financial Obligations Liabilityfor Unpaid Claims Adjustment Expense Claims Paid InsuredFinancialObligationsLiabilityforUnpaidClaimsAdjustmentExpenseClaimsPaid	17000000	USD
CY2019Q3	ago	Expected Loss Adjustment Expense To Be Paid ExpectedLossAdjustmentExpenseToBePaid	34000000	USD
CY2018Q4	ago	Expected Loss Adjustment Expense To Be Paid ExpectedLossAdjustmentExpenseToBePaid	31000000	USD
CY2019Q3	ago	Guarantor Obligations Net Expected Losstobe Paid After Recoveriesfor Representationsand Warranties GuarantorObligationsNetExpectedLosstobePaidAfterRecoveriesforRepresentationsandWarranties	718000000	USD
CY2018Q4	ago	Guarantor Obligations Net Expected Losstobe Paid After Recoveriesfor Representationsand Warranties GuarantorObligationsNetExpectedLosstobePaidAfterRecoveriesforRepresentationsandWarranties	1183000000	USD
CY2019Q3	ago	Guarantor Obligations Net Expected Loss Development After Recoveriesfor Representationsand Warranties GuarantorObligationsNetExpectedLossDevelopmentAfterRecoveriesforRepresentationsandWarranties	25000000	USD
CY2018Q3	ago	Guarantor Obligations Net Expected Loss Development After Recoveriesfor Representationsand Warranties GuarantorObligationsNetExpectedLossDevelopmentAfterRecoveriesforRepresentationsandWarranties	0	USD
	ago	Guarantor Obligations Net Expected Loss Development After Recoveriesfor Representationsand Warranties GuarantorObligationsNetExpectedLossDevelopmentAfterRecoveriesforRepresentationsandWarranties	-14000000	USD
	ago	Guarantor Obligations Net Expected Loss Development After Recoveriesfor Representationsand Warranties GuarantorObligationsNetExpectedLossDevelopmentAfterRecoveriesforRepresentationsandWarranties	-5000000	USD
CY2019Q3	ago	Additional Loss Recovery Assumption AdditionalLossRecoveryAssumption	0.20
CY2018Q4	ago	Additional Loss Recovery Assumption AdditionalLossRecoveryAssumption	0.10
	ago	Additional Loss Recovery Assumption Recovery Period AdditionalLossRecoveryAssumptionRecoveryPeriod	P5Y
CY2019Q3	ago	Loss Recovery Assumption Additional Increasein Recovery Projection Percent LossRecoveryAssumptionAdditionalIncreaseinRecoveryProjectionPercent	0.30
CY2019Q3	ago	Loss Recovery Assumption Additional Increasein Recovery Projection Economic Benefit LossRecoveryAssumptionAdditionalIncreaseinRecoveryProjectionEconomicBenefit	61000000	USD
CY2019Q3	ago	Loss Recovery Assumption Additional Decreasein Recovery Projection Percent LossRecoveryAssumptionAdditionalDecreaseinRecoveryProjectionPercent	0.10
CY2019Q3	ago	Loss Recovery Assumption Additional Decreasein Recovery Projection Economic Loss LossRecoveryAssumptionAdditionalDecreaseinRecoveryProjectionEconomicLoss	61000000	USD
CY2019Q3	ago	Financial Guarantee Insurance Contracts Scheduled Net Earned Premiums FinancialGuaranteeInsuranceContractsScheduledNetEarnedPremiums	81000000	USD
CY2018Q3	ago	Financial Guarantee Insurance Contracts Scheduled Net Earned Premiums FinancialGuaranteeInsuranceContractsScheduledNetEarnedPremiums	95000000	USD
	ago	Financial Guarantee Insurance Contracts Scheduled Net Earned Premiums FinancialGuaranteeInsuranceContractsScheduledNetEarnedPremiums	253000000	USD
	ago	Financial Guarantee Insurance Contracts Scheduled Net Earned Premiums FinancialGuaranteeInsuranceContractsScheduledNetEarnedPremiums	275000000	USD
CY2019Q3	us-gaap	Financial Guarantee Insurance Contracts Accelerated Premium Revenue Amount FinancialGuaranteeInsuranceContractsAcceleratedPremiumRevenueAmount	37000000	USD
CY2018Q3	us-gaap	Financial Guarantee Insurance Contracts Accelerated Premium Revenue Amount FinancialGuaranteeInsuranceContractsAcceleratedPremiumRevenueAmount	40000000	USD
	us-gaap	Financial Guarantee Insurance Contracts Accelerated Premium Revenue Amount FinancialGuaranteeInsuranceContractsAcceleratedPremiumRevenueAmount	83000000	USD
	us-gaap	Financial Guarantee Insurance Contracts Accelerated Premium Revenue Amount FinancialGuaranteeInsuranceContractsAcceleratedPremiumRevenueAmount	131000000	USD
CY2019Q3	ago	Financial Guarantee Insurance Contracts Net Premiums Receivable Adjustment Accretionof Discounton Net Premium Receivable FinancialGuaranteeInsuranceContractsNetPremiumsReceivableAdjustmentAccretionofDiscountonNetPremiumReceivable	-4000000	USD
CY2018Q3	ago	Financial Guarantee Insurance Contracts Net Premiums Receivable Adjustment Accretionof Discounton Net Premium Receivable FinancialGuaranteeInsuranceContractsNetPremiumsReceivableAdjustmentAccretionofDiscountonNetPremiumReceivable	-6000000	USD
	ago	Financial Guarantee Insurance Contracts Net Premiums Receivable Adjustment Accretionof Discounton Net Premium Receivable FinancialGuaranteeInsuranceContractsNetPremiumsReceivableAdjustmentAccretionofDiscountonNetPremiumReceivable	-13000000	USD
	ago	Financial Guarantee Insurance Contracts Net Premiums Receivable Adjustment Accretionof Discounton Net Premium Receivable FinancialGuaranteeInsuranceContractsNetPremiumsReceivableAdjustmentAccretionofDiscountonNetPremiumReceivable	-14000000	USD
CY2019Q3	ago	Financial Guarantee Insurance Contracts Premiums Earned Net FinancialGuaranteeInsuranceContractsPremiumsEarnedNet	122000000	USD
CY2018Q3	ago	Financial Guarantee Insurance Contracts Premiums Earned Net FinancialGuaranteeInsuranceContractsPremiumsEarnedNet	141000000	USD
	ago	Financial Guarantee Insurance Contracts Premiums Earned Net FinancialGuaranteeInsuranceContractsPremiumsEarnedNet	349000000	USD
	ago	Financial Guarantee Insurance Contracts Premiums Earned Net FinancialGuaranteeInsuranceContractsPremiumsEarnedNet	420000000	USD
CY2019Q3	ago	Premiums Earned Net Non Financial Guarantee PremiumsEarnedNetNonFinancialGuarantee	1000000	USD
CY2018Q3	ago	Premiums Earned Net Non Financial Guarantee PremiumsEarnedNetNonFinancialGuarantee	1000000	USD
	ago	Premiums Earned Net Non Financial Guarantee PremiumsEarnedNetNonFinancialGuarantee	4000000	USD
	ago	Premiums Earned Net Non Financial Guarantee PremiumsEarnedNetNonFinancialGuarantee	3000000	USD
CY2019Q3	us-gaap	Premiums Earned Net PremiumsEarnedNet	123000000	USD
CY2018Q3	us-gaap	Premiums Earned Net PremiumsEarnedNet	142000000	USD
	us-gaap	Premiums Earned Net PremiumsEarnedNet	353000000	USD
	us-gaap	Premiums Earned Net PremiumsEarnedNet	423000000	USD
CY2018Q4	us-gaap	Financial Guarantee Insurance Contracts Premium Receivable FinancialGuaranteeInsuranceContractsPremiumReceivable	904000000	USD
CY2017Q4	us-gaap	Financial Guarantee Insurance Contracts Premium Receivable FinancialGuaranteeInsuranceContractsPremiumReceivable	915000000	USD
CY2018Q4	ago	Financial Guarantee Insurance Contracts Premium Receivable Other FinancialGuaranteeInsuranceContractsPremiumReceivableOther	1000000	USD
CY2017Q4	ago	Financial Guarantee Insurance Contracts Premium Receivable Other FinancialGuaranteeInsuranceContractsPremiumReceivableOther	1000000	USD
CY2018Q4	ago	Financial Guarantee Insurance Contracts Premium Receivable Excluding Other Non Financial Guarantee FinancialGuaranteeInsuranceContractsPremiumReceivableExcludingOtherNonFinancialGuarantee	903000000	USD
CY2017Q4	ago	Financial Guarantee Insurance Contracts Premium Receivable Excluding Other Non Financial Guarantee FinancialGuaranteeInsuranceContractsPremiumReceivableExcludingOtherNonFinancialGuarantee	914000000	USD
	us-gaap	Financial Guarantee Insurance Contracts Premium Receivable New Business Written FinancialGuaranteeInsuranceContractsPremiumReceivableNewBusinessWritten	164000000	USD
	us-gaap	Financial Guarantee Insurance Contracts Premium Receivable New Business Written FinancialGuaranteeInsuranceContractsPremiumReceivableNewBusinessWritten	508000000	USD
	us-gaap	Financial Guarantee Insurance Contracts Premium Receivable Proceeds From Premiums Received FinancialGuaranteeInsuranceContractsPremiumReceivableProceedsFromPremiumsReceived	198000000	USD
	us-gaap	Financial Guarantee Insurance Contracts Premium Receivable Proceeds From Premiums Received FinancialGuaranteeInsuranceContractsPremiumReceivableProceedsFromPremiumsReceived	477000000	USD
	us-gaap	Financial Guarantee Insurance Contracts Premiums Receivable Adjustment Change In Period Of Contract FinancialGuaranteeInsuranceContractsPremiumsReceivableAdjustmentChangeInPeriodOfContract	-10000000	USD
	us-gaap	Financial Guarantee Insurance Contracts Premiums Receivable Adjustment Change In Period Of Contract FinancialGuaranteeInsuranceContractsPremiumsReceivableAdjustmentChangeInPeriodOfContract	-2000000	USD
	us-gaap	Financial Guarantee Insurance Contracts Premiums Receivable Accretion Of Discount On Premium Receivable FinancialGuaranteeInsuranceContractsPremiumsReceivableAccretionOfDiscountOnPremiumReceivable	8000000	USD
	us-gaap	Financial Guarantee Insurance Contracts Premiums Receivable Accretion Of Discount On Premium Receivable FinancialGuaranteeInsuranceContractsPremiumsReceivableAccretionOfDiscountOnPremiumReceivable	5000000	USD
	ago	Financial Guarantee Insurance Contracts Premiums Receivable Adjustment Foreign Exchange Translation FinancialGuaranteeInsuranceContractsPremiumsReceivableAdjustmentForeignExchangeTranslation	-24000000	USD
	ago	Financial Guarantee Insurance Contracts Premiums Receivable Adjustment Foreign Exchange Translation FinancialGuaranteeInsuranceContractsPremiumsReceivableAdjustmentForeignExchangeTranslation	-23000000	USD
	us-gaap	Financial Guarantee Insurance Contracts Premiums Receivable Adjustment Other Adjustments FinancialGuaranteeInsuranceContractsPremiumsReceivableAdjustmentOtherAdjustments	0	USD
	us-gaap	Financial Guarantee Insurance Contracts Premiums Receivable Adjustment Other Adjustments FinancialGuaranteeInsuranceContractsPremiumsReceivableAdjustmentOtherAdjustments	-10000000	USD
CY2019Q3	ago	Financial Guarantee Insurance Contracts Premium Receivable Excluding Other Non Financial Guarantee FinancialGuaranteeInsuranceContractsPremiumReceivableExcludingOtherNonFinancialGuarantee	843000000	USD
CY2018Q3	ago	Financial Guarantee Insurance Contracts Premium Receivable Excluding Other Non Financial Guarantee FinancialGuaranteeInsuranceContractsPremiumReceivableExcludingOtherNonFinancialGuarantee	915000000	USD
CY2019Q3	ago	Financial Guarantee Insurance Contracts Premium Receivable Other FinancialGuaranteeInsuranceContractsPremiumReceivableOther	1000000	USD
CY2018Q3	ago	Financial Guarantee Insurance Contracts Premium Receivable Other FinancialGuaranteeInsuranceContractsPremiumReceivableOther	1000000	USD
CY2019Q3	us-gaap	Financial Guarantee Insurance Contracts Premium Receivable FinancialGuaranteeInsuranceContractsPremiumReceivable	844000000	USD
CY2018Q3	us-gaap	Financial Guarantee Insurance Contracts Premium Receivable FinancialGuaranteeInsuranceContractsPremiumReceivable	916000000	USD
	us-gaap	Financial Guarantee Insurance Contracts Claim Liability Weighted Average Risk Free Discount Rate FinancialGuaranteeInsuranceContractsClaimLiabilityWeightedAverageRiskFreeDiscountRate	0.0180
CY2018	us-gaap	Financial Guarantee Insurance Contracts Claim Liability Weighted Average Risk Free Discount Rate FinancialGuaranteeInsuranceContractsClaimLiabilityWeightedAverageRiskFreeDiscountRate	0.0274
CY2019Q3	ago	Reserve For Losses And Loss Adjustment Expenses Net Of Reinsurance And Salvage And Subrogation Recoveries ReserveForLossesAndLossAdjustmentExpensesNetOfReinsuranceAndSalvageAndSubrogationRecoveries	272000000	USD
CY2018Q4	ago	Reserve For Losses And Loss Adjustment Expenses Net Of Reinsurance And Salvage And Subrogation Recoveries ReserveForLossesAndLossAdjustmentExpensesNetOfReinsuranceAndSalvageAndSubrogationRecoveries	674000000	USD
CY2019Q3	us-gaap	Liability For Claims And Claims Adjustment Expense LiabilityForClaimsAndClaimsAdjustmentExpense	1007000000	USD
CY2018Q4	us-gaap	Liability For Claims And Claims Adjustment Expense LiabilityForClaimsAndClaimsAdjustmentExpense	1177000000	USD
CY2019Q3	us-gaap	Reinsurance Recoverable For Unpaid Claims And Claims Adjustments ReinsuranceRecoverableForUnpaidClaimsAndClaimsAdjustments	36000000	USD
CY2018Q4	us-gaap	Reinsurance Recoverable For Unpaid Claims And Claims Adjustments ReinsuranceRecoverableForUnpaidClaimsAndClaimsAdjustments	34000000	USD
CY2019Q3	us-gaap	Liability For Unpaid Claims And Claims Adjustment Expense Net LiabilityForUnpaidClaimsAndClaimsAdjustmentExpenseNet	971000000	USD
CY2018Q4	us-gaap	Liability For Unpaid Claims And Claims Adjustment Expense Net LiabilityForUnpaidClaimsAndClaimsAdjustmentExpenseNet	1143000000	USD
CY2019Q3	us-gaap	Salvage And Subrogation Recoveries Value SalvageAndSubrogationRecoveriesValue	725000000	USD
CY2018Q4	us-gaap	Salvage And Subrogation Recoveries Value SalvageAndSubrogationRecoveriesValue	490000000	USD
CY2019Q3	ago	Ceded Salvage And Subrogation Recoveries Value CededSalvageAndSubrogationRecoveriesValue	26000000	USD
CY2018Q4	ago	Ceded Salvage And Subrogation Recoveries Value CededSalvageAndSubrogationRecoveriesValue	24000000	USD
CY2019Q3	ago	Payable Liabilityfor Unpaid Claimsand Claims Adjustment Expense Other Recoverable PayableLiabilityforUnpaidClaimsandClaimsAdjustmentExpenseOtherRecoverable	0	USD
CY2018Q4	ago	Payable Liabilityfor Unpaid Claimsand Claims Adjustment Expense Other Recoverable PayableLiabilityforUnpaidClaimsandClaimsAdjustmentExpenseOtherRecoverable	-3000000	USD
CY2019Q3	ago	Reservefor Lossesand Loss Adjustment Expenses Netof Reinsuranceand Salvageand Subrogation Including Other Recoverables ReserveforLossesandLossAdjustmentExpensesNetofReinsuranceandSalvageandSubrogationIncludingOtherRecoverables	-699000000	USD
CY2018Q4	ago	Reservefor Lossesand Loss Adjustment Expenses Netof Reinsuranceand Salvageand Subrogation Including Other Recoverables ReserveforLossesandLossAdjustmentExpensesNetofReinsuranceandSalvageandSubrogationIncludingOtherRecoverables	-469000000	USD
CY2019Q3	ago	Liabilityfor Unpaid Claimsand Claims Adjustment Expense Netof Reinsuranceand Salvage Subrogationand Other Recoveries LiabilityforUnpaidClaimsandClaimsAdjustmentExpenseNetofReinsuranceandSalvageSubrogationandOtherRecoveries	272000000	USD
CY2018Q4	ago	Liabilityfor Unpaid Claimsand Claims Adjustment Expense Netof Reinsuranceand Salvage Subrogationand Other Recoveries LiabilityforUnpaidClaimsandClaimsAdjustmentExpenseNetofReinsuranceandSalvageSubrogationandOtherRecoveries	674000000	USD
CY2019Q3	ago	Financial Guarantee Insurance Contracts Future Expected Net Losstobe Expensed During Fourth Quarter Following Balance Sheet Date FinancialGuaranteeInsuranceContractsFutureExpectedNetLosstobeExpensedDuringFourthQuarterFollowingBalanceSheetDate	9000000	USD
CY2019Q3	ago	Financial Guarantee Insurance Contracts Future Expected Net Losstobe Expensedin Second Full Fiscal Year FinancialGuaranteeInsuranceContractsFutureExpectedNetLosstobeExpensedinSecondFullFiscalYear	37000000	USD
CY2019Q3	ago	Financial Guarantee Insurance Contracts Future Expected Net Losstobe Expensedin Third Full Fiscal Year FinancialGuaranteeInsuranceContractsFutureExpectedNetLosstobeExpensedinThirdFullFiscalYear	36000000	USD
CY2019Q3	ago	Financial Guarantee Insurance Contracts Future Expected Net Losstobe Expensedin Fourth Full Fiscal Year FinancialGuaranteeInsuranceContractsFutureExpectedNetLosstobeExpensedinFourthFullFiscalYear	35000000	USD
CY2019Q3	ago	Financial Guarantee Insurance Contracts Future Expected Net Losstobe Expensedin Fifth Full Fiscal Year FinancialGuaranteeInsuranceContractsFutureExpectedNetLosstobeExpensedinFifthFullFiscalYear	31000000	USD
CY2019Q3	ago	Financial Guarantee Insurance Contracts Future Expected Net Losstobe Expensed Morethan Fiveand Within10 Yearsfrom Balance Sheet Date FinancialGuaranteeInsuranceContractsFutureExpectedNetLosstobeExpensedMorethanFiveandWithin10YearsfromBalanceSheetDate	147000000	USD
CY2019Q3	ago	Financial Guarantee Insurance Contracts Future Expected Net Losstobe Expensed Morethan10andwithin15 Yearsfrom Balance Sheet Date FinancialGuaranteeInsuranceContractsFutureExpectedNetLosstobeExpensedMorethan10andwithin15YearsfromBalanceSheetDate	99000000	USD
CY2019Q3	ago	Financial Guarantee Insurance Contracts Future Expected Net Losstobe Expensed Morethan15andwithin20 Yearsfrom Balance Sheet Date FinancialGuaranteeInsuranceContractsFutureExpectedNetLosstobeExpensedMorethan15andwithin20YearsfromBalanceSheetDate	45000000	USD
CY2019Q3	ago	Financial Guarantee Insurance Contracts Future Expected Net Losstobe Expensed Beyond Twentieth Fiscal Year FinancialGuaranteeInsuranceContractsFutureExpectedNetLosstobeExpensedBeyondTwentiethFiscalYear	9000000	USD
CY2019Q3	ago	Financial Guarantee Insurance Contracts Net Losstobe Expensed Present Value FinancialGuaranteeInsuranceContractsNetLosstobeExpensedPresentValue	448000000	USD
CY2019Q3	ago	Scheduleof Insured Financial Obligationswith Credit Deterioration Reductionsof Gross Claim Liability Netof Reinsurance Recoverable Discount ScheduleofInsuredFinancialObligationswithCreditDeteriorationReductionsofGrossClaimLiabilityNetofReinsuranceRecoverableDiscount	30000000	USD
CY2019Q3	ago	Financial Guarantee Insurance Contracts Net Losstobe Expensed Undiscounted FinancialGuaranteeInsuranceContractsNetLosstobeExpensedUndiscounted	478000000	USD
CY2019Q3	us-gaap	Policyholder Benefits And Claims Incurred Net PolicyholderBenefitsAndClaimsIncurredNet	30000000	USD
CY2018Q3	us-gaap	Policyholder Benefits And Claims Incurred Net PolicyholderBenefitsAndClaimsIncurredNet	17000000	USD
	us-gaap	Policyholder Benefits And Claims Incurred Net PolicyholderBenefitsAndClaimsIncurredNet	75000000	USD
	us-gaap	Policyholder Benefits And Claims Incurred Net PolicyholderBenefitsAndClaimsIncurredNet	43000000	USD
CY2018Q4	ago	Percentage Of Cds Contracts Fair Valued Using Minimum Premium PercentageOfCdsContractsFairValuedUsingMinimumPremium	0.17
CY2019Q3	us-gaap	Accrued Investment Income Receivable AccruedInvestmentIncomeReceivable	86000000	USD
CY2018Q4	us-gaap	Accrued Investment Income Receivable AccruedInvestmentIncomeReceivable	91000000	USD
CY2019Q3	us-gaap	Interest And Dividend Income Operating InterestAndDividendIncomeOperating	90000000	USD
CY2018Q3	us-gaap	Interest And Dividend Income Operating InterestAndDividendIncomeOperating	101000000	USD
	us-gaap	Interest And Dividend Income Operating InterestAndDividendIncomeOperating	302000000	USD
	us-gaap	Interest And Dividend Income Operating InterestAndDividendIncomeOperating	304000000	USD
CY2019Q3	us-gaap	Investment Income Investment Expense InvestmentIncomeInvestmentExpense	2000000	USD
CY2018Q3	us-gaap	Investment Income Investment Expense InvestmentIncomeInvestmentExpense	2000000	USD
	us-gaap	Investment Income Investment Expense InvestmentIncomeInvestmentExpense	6000000	USD
	us-gaap	Investment Income Investment Expense InvestmentIncomeInvestmentExpense	7000000	USD
CY2019Q3	us-gaap	Net Investment Income NetInvestmentIncome	88000000	USD
CY2018Q3	us-gaap	Net Investment Income NetInvestmentIncome	99000000	USD
	us-gaap	Net Investment Income NetInvestmentIncome	296000000	USD
	us-gaap	Net Investment Income NetInvestmentIncome	297000000	USD
CY2019Q3	us-gaap	Available For Sale Securities Gross Realized Gains AvailableForSaleSecuritiesGrossRealizedGains	29000000	USD
CY2018Q3	us-gaap	Available For Sale Securities Gross Realized Gains AvailableForSaleSecuritiesGrossRealizedGains	5000000	USD
	us-gaap	Available For Sale Securities Gross Realized Gains AvailableForSaleSecuritiesGrossRealizedGains	48000000	USD
	us-gaap	Available For Sale Securities Gross Realized Gains AvailableForSaleSecuritiesGrossRealizedGains	16000000	USD
CY2019Q3	us-gaap	Available For Sale Securities Gross Realized Losses AvailableForSaleSecuritiesGrossRealizedLosses	1000000	USD
CY2018Q3	us-gaap	Available For Sale Securities Gross Realized Losses AvailableForSaleSecuritiesGrossRealizedLosses	3000000	USD
	us-gaap	Available For Sale Securities Gross Realized Losses AvailableForSaleSecuritiesGrossRealizedLosses	4000000	USD
	us-gaap	Available For Sale Securities Gross Realized Losses AvailableForSaleSecuritiesGrossRealizedLosses	9000000	USD
CY2019Q3	ago	Net Realized Investment Gains Losses NetRealizedInvestmentGainsLosses	0	USD
CY2018Q3	ago	Net Realized Investment Gains Losses NetRealizedInvestmentGainsLosses	0	USD
	ago	Net Realized Investment Gains Losses NetRealizedInvestmentGainsLosses	0	USD
	ago	Net Realized Investment Gains Losses NetRealizedInvestmentGainsLosses	1000000	USD
CY2019Q3	ago	Other Than Temporary Impairment Losses OtherThanTemporaryImpairmentLosses	12000000	USD
CY2018Q3	ago	Other Than Temporary Impairment Losses OtherThanTemporaryImpairmentLosses	8000000	USD
	ago	Other Than Temporary Impairment Losses OtherThanTemporaryImpairmentLosses	29000000	USD
	ago	Other Than Temporary Impairment Losses OtherThanTemporaryImpairmentLosses	23000000	USD
CY2019Q3	us-gaap	Other Than Temporary Impairment Losses Investments Portion In Other Comprehensive Income Loss Before Tax Including Portion Attributable To Noncontrolling Interest Availableforsale Securities OtherThanTemporaryImpairmentLossesInvestmentsPortionInOtherComprehensiveIncomeLossBeforeTaxIncludingPortionAttributableToNoncontrollingInterestAvailableforsaleSecurities	0	USD
CY2018Q3	us-gaap	Other Than Temporary Impairment Losses Investments Portion In Other Comprehensive Income Loss Before Tax Including Portion Attributable To Noncontrolling Interest Availableforsale Securities OtherThanTemporaryImpairmentLossesInvestmentsPortionInOtherComprehensiveIncomeLossBeforeTaxIncludingPortionAttributableToNoncontrollingInterestAvailableforsaleSecurities	1000000	USD
	us-gaap	Other Than Temporary Impairment Losses Investments Portion In Other Comprehensive Income Loss Before Tax Including Portion Attributable To Noncontrolling Interest Availableforsale Securities OtherThanTemporaryImpairmentLossesInvestmentsPortionInOtherComprehensiveIncomeLossBeforeTaxIncludingPortionAttributableToNoncontrollingInterestAvailableforsaleSecurities	3000000	USD
	us-gaap	Other Than Temporary Impairment Losses Investments Portion In Other Comprehensive Income Loss Before Tax Including Portion Attributable To Noncontrolling Interest Availableforsale Securities OtherThanTemporaryImpairmentLossesInvestmentsPortionInOtherComprehensiveIncomeLossBeforeTaxIncludingPortionAttributableToNoncontrollingInterestAvailableforsaleSecurities	-3000000	USD
CY2019Q3	us-gaap	Other Than Temporary Impairment Losses Investments Portion In Other Comprehensive Income Loss Net Of Tax Including Portion Attributable To Noncontrolling Interest Availableforsale Securities OtherThanTemporaryImpairmentLossesInvestmentsPortionInOtherComprehensiveIncomeLossNetOfTaxIncludingPortionAttributableToNoncontrollingInterestAvailableforsaleSecurities	12000000	USD
CY2018Q3	us-gaap	Other Than Temporary Impairment Losses Investments Portion In Other Comprehensive Income Loss Net Of Tax Including Portion Attributable To Noncontrolling Interest Availableforsale Securities OtherThanTemporaryImpairmentLossesInvestmentsPortionInOtherComprehensiveIncomeLossNetOfTaxIncludingPortionAttributableToNoncontrollingInterestAvailableforsaleSecurities	9000000	USD
	us-gaap	Other Than Temporary Impairment Losses Investments Portion In Other Comprehensive Income Loss Net Of Tax Including Portion Attributable To Noncontrolling Interest Availableforsale Securities OtherThanTemporaryImpairmentLossesInvestmentsPortionInOtherComprehensiveIncomeLossNetOfTaxIncludingPortionAttributableToNoncontrollingInterestAvailableforsaleSecurities	32000000	USD
	us-gaap	Other Than Temporary Impairment Losses Investments Portion In Other Comprehensive Income Loss Net Of Tax Including Portion Attributable To Noncontrolling Interest Availableforsale Securities OtherThanTemporaryImpairmentLossesInvestmentsPortionInOtherComprehensiveIncomeLossNetOfTaxIncludingPortionAttributableToNoncontrollingInterestAvailableforsaleSecurities	20000000	USD
CY2019Q3	us-gaap	Realized Investment Gains Losses RealizedInvestmentGainsLosses	16000000	USD
CY2018Q3	us-gaap	Realized Investment Gains Losses RealizedInvestmentGainsLosses	-7000000	USD
	us-gaap	Realized Investment Gains Losses RealizedInvestmentGainsLosses	12000000	USD
	us-gaap	Realized Investment Gains Losses RealizedInvestmentGainsLosses	-14000000	USD
CY2019Q3	us-gaap	Proceeds From Sale Of Available For Sale Securities Debt ProceedsFromSaleOfAvailableForSaleSecuritiesDebt	405000000	USD
CY2018Q3	us-gaap	Proceeds From Sale Of Available For Sale Securities Debt ProceedsFromSaleOfAvailableForSaleSecuritiesDebt	316000000	USD
	us-gaap	Proceeds From Sale Of Available For Sale Securities Debt ProceedsFromSaleOfAvailableForSaleSecuritiesDebt	1306000000	USD
	us-gaap	Proceeds From Sale Of Available For Sale Securities Debt ProceedsFromSaleOfAvailableForSaleSecuritiesDebt	908000000	USD
	ago	Noncash Paymentsto Acquire Fixed Maturity Securities Availablefor Sale NoncashPaymentstoAcquireFixedMaturitySecuritiesAvailableforSale	144000000	USD
	ago	Noncash Paymentsto Acquire Fixed Maturity Securities Availablefor Sale NoncashPaymentstoAcquireFixedMaturitySecuritiesAvailableforSale	4000000	USD
CY2019Q2	us-gaap	Other Than Temporary Impairment Credit Losses Recognized In Earnings Credit Losses On Debt Securities Held OtherThanTemporaryImpairmentCreditLossesRecognizedInEarningsCreditLossesOnDebtSecuritiesHeld	191000000	USD
CY2018Q2	us-gaap	Other Than Temporary Impairment Credit Losses Recognized In Earnings Credit Losses On Debt Securities Held OtherThanTemporaryImpairmentCreditLossesRecognizedInEarningsCreditLossesOnDebtSecuritiesHeld	170000000	USD
CY2018Q4	us-gaap	Other Than Temporary Impairment Credit Losses Recognized In Earnings Credit Losses On Debt Securities Held OtherThanTemporaryImpairmentCreditLossesRecognizedInEarningsCreditLossesOnDebtSecuritiesHeld	185000000	USD
CY2017Q4	us-gaap	Other Than Temporary Impairment Credit Losses Recognized In Earnings Credit Losses On Debt Securities Held OtherThanTemporaryImpairmentCreditLossesRecognizedInEarningsCreditLossesOnDebtSecuritiesHeld	162000000	USD
CY2019Q3	us-gaap	Other Than Temporary Impairment Credit Losses Recognized In Earnings Additions Additional Credit Losses OtherThanTemporaryImpairmentCreditLossesRecognizedInEarningsAdditionsAdditionalCreditLosses	0	USD
CY2018Q3	us-gaap	Other Than Temporary Impairment Credit Losses Recognized In Earnings Additions Additional Credit Losses OtherThanTemporaryImpairmentCreditLossesRecognizedInEarningsAdditionsAdditionalCreditLosses	2000000	USD
	us-gaap	Other Than Temporary Impairment Credit Losses Recognized In Earnings Additions Additional Credit Losses OtherThanTemporaryImpairmentCreditLossesRecognizedInEarningsAdditionsAdditionalCreditLosses	13000000	USD
	us-gaap	Other Than Temporary Impairment Credit Losses Recognized In Earnings Additions Additional Credit Losses OtherThanTemporaryImpairmentCreditLossesRecognizedInEarningsAdditionsAdditionalCreditLosses	10000000	USD
CY2019Q3	us-gaap	Other Than Temporary Impairment Credit Losses Recognized In Earnings Reductions Securities Sold OtherThanTemporaryImpairmentCreditLossesRecognizedInEarningsReductionsSecuritiesSold	0	USD
CY2018Q3	us-gaap	Other Than Temporary Impairment Credit Losses Recognized In Earnings Reductions Securities Sold OtherThanTemporaryImpairmentCreditLossesRecognizedInEarningsReductionsSecuritiesSold	0	USD
	us-gaap	Other Than Temporary Impairment Credit Losses Recognized In Earnings Reductions Securities Sold OtherThanTemporaryImpairmentCreditLossesRecognizedInEarningsReductionsSecuritiesSold	7000000	USD
	us-gaap	Other Than Temporary Impairment Credit Losses Recognized In Earnings Reductions Securities Sold OtherThanTemporaryImpairmentCreditLossesRecognizedInEarningsReductionsSecuritiesSold	0	USD
CY2019Q3	us-gaap	Other Than Temporary Impairment Credit Losses Recognized In Earnings Credit Losses On Debt Securities Held OtherThanTemporaryImpairmentCreditLossesRecognizedInEarningsCreditLossesOnDebtSecuritiesHeld	191000000	USD
CY2018Q3	us-gaap	Other Than Temporary Impairment Credit Losses Recognized In Earnings Credit Losses On Debt Securities Held OtherThanTemporaryImpairmentCreditLossesRecognizedInEarningsCreditLossesOnDebtSecuritiesHeld	172000000	USD
CY2019Q3	us-gaap	Other Than Temporary Impairment Credit Losses Recognized In Earnings Credit Losses On Debt Securities Held OtherThanTemporaryImpairmentCreditLossesRecognizedInEarningsCreditLossesOnDebtSecuritiesHeld	191000000	USD
CY2018Q3	us-gaap	Other Than Temporary Impairment Credit Losses Recognized In Earnings Credit Losses On Debt Securities Held OtherThanTemporaryImpairmentCreditLossesRecognizedInEarningsCreditLossesOnDebtSecuritiesHeld	172000000	USD
	ago	Numberof Outside Managers Managing Investment Portfolio NumberofOutsideManagersManagingInvestmentPortfolio	7	manager
CY2019Q3	us-gaap	Short Term Investments ShortTermInvestments	1142000000	USD
CY2018Q4	us-gaap	Short Term Investments ShortTermInvestments	729000000	USD
CY2019Q3	us-gaap	Investments Investments	10476000000	USD
CY2018Q4	us-gaap	Investments Investments	10873000000	USD
CY2019Q3	ago	Percentageof Availableforsale Securitiesat Amortized Cost PercentageofAvailableforsaleSecuritiesatAmortizedCost	1
CY2019Q3	us-gaap	Available For Sale Debt Securities Amortized Cost Basis AvailableForSaleDebtSecuritiesAmortizedCostBasis	9953000000	USD
CY2019Q3	us-gaap	Available For Sale Debt Securities Accumulated Gross Unrealized Gain Before Tax AvailableForSaleDebtSecuritiesAccumulatedGrossUnrealizedGainBeforeTax	518000000	USD
CY2019Q3	us-gaap	Available For Sale Debt Securities Accumulated Gross Unrealized Loss Before Tax AvailableForSaleDebtSecuritiesAccumulatedGrossUnrealizedLossBeforeTax	52000000	USD
CY2019Q3	us-gaap	Available For Sale Securities Debt Securities AvailableForSaleSecuritiesDebtSecurities	10419000000	USD
CY2019Q3	ago	Accumulated Other Comprehensive Income Loss Otherthan Temporary Impairment Not Credit Loss Before Tax Debt Securities Total AccumulatedOtherComprehensiveIncomeLossOtherthanTemporaryImpairmentNotCreditLossBeforeTaxDebtSecuritiesTotal	52000000	USD
CY2018Q4	ago	Percentageof Availableforsale Securitiesat Amortized Cost PercentageofAvailableforsaleSecuritiesatAmortizedCost	1
CY2018Q4	us-gaap	Available For Sale Debt Securities Amortized Cost Basis AvailableForSaleDebtSecuritiesAmortizedCostBasis	10613000000	USD
CY2018Q4	us-gaap	Available For Sale Debt Securities Accumulated Gross Unrealized Gain Before Tax AvailableForSaleDebtSecuritiesAccumulatedGrossUnrealizedGainBeforeTax	344000000	USD
CY2018Q4	us-gaap	Available For Sale Debt Securities Accumulated Gross Unrealized Loss Before Tax AvailableForSaleDebtSecuritiesAccumulatedGrossUnrealizedLossBeforeTax	139000000	USD
CY2018Q4	us-gaap	Available For Sale Securities Debt Securities AvailableForSaleSecuritiesDebtSecurities	10818000000	USD
CY2018Q4	ago	Accumulated Other Comprehensive Income Loss Otherthan Temporary Impairment Not Credit Loss Before Tax Debt Securities Total AccumulatedOtherComprehensiveIncomeLossOtherthanTemporaryImpairmentNotCreditLossBeforeTaxDebtSecuritiesTotal	118000000	USD
CY2019Q3	ago	Government Agency Obligations As Percentage Of Total Mortgage Backed Securities GovernmentAgencyObligationsAsPercentageOfTotalMortgageBackedSecurities	0.44
CY2018Q4	ago	Government Agency Obligations As Percentage Of Total Mortgage Backed Securities GovernmentAgencyObligationsAsPercentageOfTotalMortgageBackedSecurities	0.48
CY2019Q3	us-gaap	Available For Sale Securities Continuous Unrealized Loss Position Less Than Twelve Months Fair Value AvailableForSaleSecuritiesContinuousUnrealizedLossPositionLessThanTwelveMonthsFairValue	511000000	USD
CY2019Q3	us-gaap	Available For Sale Securities Continuous Unrealized Loss Position Less Than12 Months Accumulated Loss AvailableForSaleSecuritiesContinuousUnrealizedLossPositionLessThan12MonthsAccumulatedLoss	12000000	USD
CY2019Q3	us-gaap	Available For Sale Securities Continuous Unrealized Loss Position Twelve Months Or Longer Fair Value AvailableForSaleSecuritiesContinuousUnrealizedLossPositionTwelveMonthsOrLongerFairValue	602000000	USD
CY2019Q3	us-gaap	Available For Sale Securities Continuous Unrealized Loss Position12 Months Or Longer Accumulated Loss AvailableForSaleSecuritiesContinuousUnrealizedLossPosition12MonthsOrLongerAccumulatedLoss	40000000	USD
CY2019Q3	us-gaap	Available For Sale Securities Continuous Unrealized Loss Position Fair Value AvailableForSaleSecuritiesContinuousUnrealizedLossPositionFairValue	1113000000	USD
CY2019Q3	us-gaap	Available For Sale Securities Continuous Unrealized Loss Position Accumulated Loss AvailableForSaleSecuritiesContinuousUnrealizedLossPositionAccumulatedLoss	52000000	USD
CY2019Q3	us-gaap	Available For Sale Securities In Unrealized Loss Positions Qualitative Disclosure Number Of Positions Less Than One Year AvailableForSaleSecuritiesInUnrealizedLossPositionsQualitativeDisclosureNumberOfPositionsLessThanOneYear	133	Security
CY2019Q3	us-gaap	Availableforsale Securities In Unrealized Loss Positions Qualitative Disclosure Number Of Positions Greater Than Or Equal To One Year AvailableforsaleSecuritiesInUnrealizedLossPositionsQualitativeDisclosureNumberOfPositionsGreaterThanOrEqualToOneYear	143	Security
CY2019Q3	us-gaap	Availableforsale Securities In Unrealized Loss Positions Qualitative Disclosure Number Of Positions1 AvailableforsaleSecuritiesInUnrealizedLossPositionsQualitativeDisclosureNumberOfPositions1	256	Security
CY2019Q3	ago	Availableforsale Securitieswith Other Than Temporary Impairment Continuous Unrealized Loss Position Lessthan12 Months Number AvailableforsaleSecuritieswithOtherThanTemporaryImpairmentContinuousUnrealizedLossPositionLessthan12MonthsNumber	12	Security
CY2019Q3	ago	Availableforsale Securitieswith Other Than Temporary Impairment Continuous Unrealized Loss Position Twelve Monthsor Longer Number AvailableforsaleSecuritieswithOtherThanTemporaryImpairmentContinuousUnrealizedLossPositionTwelveMonthsorLongerNumber	9	Security
CY2019Q3	ago	Availableforsale Securitieswith Other Than Temporary Impairment Continuous Unrealized Loss Position Number AvailableforsaleSecuritieswithOtherThanTemporaryImpairmentContinuousUnrealizedLossPositionNumber	21	Security
CY2018Q4	us-gaap	Available For Sale Securities Continuous Unrealized Loss Position Less Than Twelve Months Fair Value AvailableForSaleSecuritiesContinuousUnrealizedLossPositionLessThanTwelveMonthsFairValue	1643000000	USD
CY2018Q4	us-gaap	Available For Sale Securities Continuous Unrealized Loss Position Less Than12 Months Accumulated Loss AvailableForSaleSecuritiesContinuousUnrealizedLossPositionLessThan12MonthsAccumulatedLoss	34000000	USD
CY2018Q4	us-gaap	Available For Sale Securities Continuous Unrealized Loss Position Twelve Months Or Longer Fair Value AvailableForSaleSecuritiesContinuousUnrealizedLossPositionTwelveMonthsOrLongerFairValue	1952000000	USD
CY2018Q4	us-gaap	Available For Sale Securities Continuous Unrealized Loss Position12 Months Or Longer Accumulated Loss AvailableForSaleSecuritiesContinuousUnrealizedLossPosition12MonthsOrLongerAccumulatedLoss	105000000	USD
CY2018Q4	us-gaap	Available For Sale Securities Continuous Unrealized Loss Position Fair Value AvailableForSaleSecuritiesContinuousUnrealizedLossPositionFairValue	3595000000	USD
CY2018Q4	us-gaap	Available For Sale Securities Continuous Unrealized Loss Position Accumulated Loss AvailableForSaleSecuritiesContinuousUnrealizedLossPositionAccumulatedLoss	139000000	USD
CY2018Q4	us-gaap	Available For Sale Securities In Unrealized Loss Positions Qualitative Disclosure Number Of Positions Less Than One Year AvailableForSaleSecuritiesInUnrealizedLossPositionsQualitativeDisclosureNumberOfPositionsLessThanOneYear	417	Security
CY2018Q4	us-gaap	Availableforsale Securities In Unrealized Loss Positions Qualitative Disclosure Number Of Positions Greater Than Or Equal To One Year AvailableforsaleSecuritiesInUnrealizedLossPositionsQualitativeDisclosureNumberOfPositionsGreaterThanOrEqualToOneYear	608	Security
CY2018Q4	us-gaap	Availableforsale Securities In Unrealized Loss Positions Qualitative Disclosure Number Of Positions1 AvailableforsaleSecuritiesInUnrealizedLossPositionsQualitativeDisclosureNumberOfPositions1	997	Security
CY2018Q4	ago	Availableforsale Securitieswith Other Than Temporary Impairment Continuous Unrealized Loss Position Lessthan12 Months Number AvailableforsaleSecuritieswithOtherThanTemporaryImpairmentContinuousUnrealizedLossPositionLessthan12MonthsNumber	22	Security
CY2018Q4	ago	Availableforsale Securitieswith Other Than Temporary Impairment Continuous Unrealized Loss Position Twelve Monthsor Longer Number AvailableforsaleSecuritieswithOtherThanTemporaryImpairmentContinuousUnrealizedLossPositionTwelveMonthsorLongerNumber	22	Security
CY2018Q4	ago	Availableforsale Securitieswith Other Than Temporary Impairment Continuous Unrealized Loss Position Number AvailableforsaleSecuritieswithOtherThanTemporaryImpairmentContinuousUnrealizedLossPositionNumber	42	Security
CY2019Q3	ago	Available For Sale Securities Continuous Unrealized Loss Position Greater Than10 Percent Of Book Value Twelve Months Or Longer Number AvailableForSaleSecuritiesContinuousUnrealizedLossPositionGreaterThan10PercentOfBookValueTwelveMonthsOrLongerNumber	27	Security
CY2018Q4	ago	Available For Sale Securities Continuous Unrealized Loss Position Greater Than10 Percent Of Book Value Twelve Months Or Longer Number AvailableForSaleSecuritiesContinuousUnrealizedLossPositionGreaterThan10PercentOfBookValueTwelveMonthsOrLongerNumber	38	Security
CY2019Q3	ago	Available For Sale Securities Continuous Unrealized Loss Position Twelve Months Or Longer Greater Than10 Percent Book Value Aggregate Losses AvailableForSaleSecuritiesContinuousUnrealizedLossPositionTwelveMonthsOrLongerGreaterThan10PercentBookValueAggregateLosses	24000000	USD
CY2018Q4	ago	Available For Sale Securities Continuous Unrealized Loss Position Twelve Months Or Longer Greater Than10 Percent Book Value Aggregate Losses AvailableForSaleSecuritiesContinuousUnrealizedLossPositionTwelveMonthsOrLongerGreaterThan10PercentBookValueAggregateLosses	43000000	USD
CY2019Q3	us-gaap	Assets Held In Trust AssetsHeldInTrust	278000000	USD
CY2018Q4	us-gaap	Assets Held In Trust AssetsHeldInTrust	266000000	USD
	us-gaap	Average Term Of Credit Risk Derivatives1 AverageTermOfCreditRiskDerivatives1	P11Y2M12D
CY2018	us-gaap	Average Term Of Credit Risk Derivatives1 AverageTermOfCreditRiskDerivatives1	P11Y7M6D
CY2019Q3	ago	Financial Guaranty Contracts Accountedforas Credit Derivatives Outstanding Principal Amount FinancialGuarantyContractsAccountedforasCreditDerivativesOutstandingPrincipalAmount	6165000000	USD
CY2019Q3	us-gaap	Credit Risk Derivatives At Fair Value Net CreditRiskDerivativesAtFairValueNet	-208000000	USD
CY2018Q4	ago	Financial Guaranty Contracts Accountedforas Credit Derivatives Outstanding Principal Amount FinancialGuarantyContractsAccountedforasCreditDerivativesOutstandingPrincipalAmount	6182000000	USD
CY2018Q4	us-gaap	Credit Risk Derivatives At Fair Value Net CreditRiskDerivativesAtFairValueNet	-207000000	USD
CY2019Q3	ago	Expected Losson Credit Derivativeto Be Paid Recovered Including Representationand Warranty Liability Benefit ExpectedLossonCreditDerivativetoBePaidRecoveredIncludingRepresentationandWarrantyLiabilityBenefit	-5000000	USD
CY2018Q4	ago	Expected Losson Credit Derivativeto Be Paid Recovered Including Representationand Warranty Liability Benefit ExpectedLossonCreditDerivativetoBePaidRecoveredIncludingRepresentationandWarrantyLiabilityBenefit	-2000000	USD
CY2019Q3	ago	Credit Derivative Realized Gains CreditDerivativeRealizedGains	2000000	USD
CY2018Q3	ago	Credit Derivative Realized Gains CreditDerivativeRealizedGains	2000000	USD
	ago	Credit Derivative Realized Gains CreditDerivativeRealizedGains	6000000	USD
	ago	Credit Derivative Realized Gains CreditDerivativeRealizedGains	6000000	USD
CY2019Q3	ago	Credit Derivative Losses CreditDerivativeLosses	5000000	USD
CY2018Q3	ago	Credit Derivative Losses CreditDerivativeLosses	1000000	USD
	ago	Credit Derivative Losses CreditDerivativeLosses	30000000	USD
	ago	Credit Derivative Losses CreditDerivativeLosses	2000000	USD
CY2019Q3	ago	Credit Derivative Realized Gain Lossand Other Settlements CreditDerivativeRealizedGainLossandOtherSettlements	-3000000	USD
CY2018Q3	ago	Credit Derivative Realized Gain Lossand Other Settlements CreditDerivativeRealizedGainLossandOtherSettlements	1000000	USD
	ago	Credit Derivative Realized Gain Lossand Other Settlements CreditDerivativeRealizedGainLossandOtherSettlements	-24000000	USD
	ago	Credit Derivative Realized Gain Lossand Other Settlements CreditDerivativeRealizedGainLossandOtherSettlements	4000000	USD
CY2019Q3	us-gaap	Unrealized Gain Loss On Derivatives UnrealizedGainLossOnDerivatives	8000000	USD
CY2018Q3	us-gaap	Unrealized Gain Loss On Derivatives UnrealizedGainLossOnDerivatives	20000000	USD
	us-gaap	Unrealized Gain Loss On Derivatives UnrealizedGainLossOnDerivatives	-1000000	USD
	us-gaap	Unrealized Gain Loss On Derivatives UnrealizedGainLossOnDerivatives	99000000	USD
CY2019Q3	us-gaap	Derivative Gain Loss On Derivative Net DerivativeGainLossOnDerivativeNet	5000000	USD
CY2018Q3	us-gaap	Derivative Gain Loss On Derivative Net DerivativeGainLossOnDerivativeNet	21000000	USD
	us-gaap	Derivative Gain Loss On Derivative Net DerivativeGainLossOnDerivativeNet	-25000000	USD
	us-gaap	Derivative Gain Loss On Derivative Net DerivativeGainLossOnDerivativeNet	103000000	USD
CY2019Q3	ago	Credit Risk Derivatives At Fair Value Before Effect Of Credit Spread Net CreditRiskDerivativesAtFairValueBeforeEffectOfCreditSpreadNet	-306000000	USD
CY2018Q4	ago	Credit Risk Derivatives At Fair Value Before Effect Of Credit Spread Net CreditRiskDerivativesAtFairValueBeforeEffectOfCreditSpreadNet	-407000000	USD
CY2019Q3	us-gaap	Derivative Credit Risk Valuation Adjustment Derivative Liabilities DerivativeCreditRiskValuationAdjustmentDerivativeLiabilities	98000000	USD
CY2018Q4	us-gaap	Derivative Credit Risk Valuation Adjustment Derivative Liabilities DerivativeCreditRiskValuationAdjustmentDerivativeLiabilities	200000000	USD
CY2019Q3	us-gaap	Credit Risk Derivatives At Fair Value Net CreditRiskDerivativesAtFairValueNet	-208000000	USD
CY2018Q4	us-gaap	Credit Risk Derivatives At Fair Value Net CreditRiskDerivativesAtFairValueNet	-207000000	USD
CY2019Q3	us-gaap	Variable Interest Entity Entity Maximum Loss Exposure Amount VariableInterestEntityEntityMaximumLossExposureAmount	0	USD
CY2019Q3	ago	Variable Interest Entity Consolidated Carrying Amount Assets With Recourse VariableInterestEntityConsolidatedCarryingAmountAssetsWithRecourse	364000000	USD
CY2019Q3	ago	Variable Interest Entity Consolidated Carrying Amount Liabilities With Recourse VariableInterestEntityConsolidatedCarryingAmountLiabilitiesWithRecourse	388000000	USD
CY2018Q4	ago	Variable Interest Entity Consolidated Carrying Amount Assets With Recourse VariableInterestEntityConsolidatedCarryingAmountAssetsWithRecourse	467000000	USD
CY2018Q4	ago	Variable Interest Entity Consolidated Carrying Amount Liabilities With Recourse VariableInterestEntityConsolidatedCarryingAmountLiabilitiesWithRecourse	517000000	USD
CY2019Q3	ago	Variable Interest Entity Consolidated Carrying Amount Assets Without Recourse VariableInterestEntityConsolidatedCarryingAmountAssetsWithoutRecourse	105000000	USD
CY2019Q3	ago	Variable Interest Entity Consolidated Carrying Amount Liabilities Without Recourse VariableInterestEntityConsolidatedCarryingAmountLiabilitiesWithoutRecourse	105000000	USD
CY2018Q4	ago	Variable Interest Entity Consolidated Carrying Amount Assets Without Recourse VariableInterestEntityConsolidatedCarryingAmountAssetsWithoutRecourse	102000000	USD
CY2018Q4	ago	Variable Interest Entity Consolidated Carrying Amount Liabilities Without Recourse VariableInterestEntityConsolidatedCarryingAmountLiabilitiesWithoutRecourse	102000000	USD
CY2019Q3	us-gaap	Variable Interest Entity Consolidated Carrying Amount Assets VariableInterestEntityConsolidatedCarryingAmountAssets	469000000	USD
CY2019Q3	us-gaap	Variable Interest Entity Consolidated Carrying Amount Liabilities VariableInterestEntityConsolidatedCarryingAmountLiabilities	493000000	USD
CY2018Q4	us-gaap	Variable Interest Entity Consolidated Carrying Amount Assets VariableInterestEntityConsolidatedCarryingAmountAssets	569000000	USD
CY2018Q4	us-gaap	Variable Interest Entity Consolidated Carrying Amount Liabilities VariableInterestEntityConsolidatedCarryingAmountLiabilities	619000000	USD
CY2019Q3	ago	Variable Interest Entity Other Consolidated Carrying Amount Assets VariableInterestEntityOtherConsolidatedCarryingAmountAssets	91000000	USD
CY2019Q3	ago	Variable Interest Entity Other Consolidated Carrying Amount Liabilities VariableInterestEntityOtherConsolidatedCarryingAmountLiabilities	9000000	USD
CY2018Q4	ago	Variable Interest Entity Other Consolidated Carrying Amount Assets VariableInterestEntityOtherConsolidatedCarryingAmountAssets	87000000	USD
CY2018Q4	ago	Variable Interest Entity Other Consolidated Carrying Amount Liabilities VariableInterestEntityOtherConsolidatedCarryingAmountLiabilities	21000000	USD
CY2019Q3	ago	Variable Interest Entity Numberof Policies Monitored VariableInterestEntityNumberofPoliciesMonitored	18000	policy
CY2019Q3	ago	Variable Interest Entity Numberof Policies Monitored Not Withinthe Scopeof Asc810 VariableInterestEntityNumberofPoliciesMonitoredNotWithintheScopeofASC810	15000	policy
CY2019Q3	ago	Variable Interest Entity Numberof Policiesthat Contain Provisionsfor Consolidation VariableInterestEntityNumberofPoliciesthatContainProvisionsforConsolidation	96	policy
CY2018Q4	ago	Variable Interest Entity Numberof Policiesthat Contain Provisionsfor Consolidation VariableInterestEntityNumberofPoliciesthatContainProvisionsforConsolidation	110	policy
CY2019Q3	us-gaap	Income Tax Reconciliation Income Tax Expense Benefit At Federal Statutory Income Tax Rate IncomeTaxReconciliationIncomeTaxExpenseBenefitAtFederalStatutoryIncomeTaxRate	17000000	USD
CY2018Q3	us-gaap	Income Tax Reconciliation Income Tax Expense Benefit At Federal Statutory Income Tax Rate IncomeTaxReconciliationIncomeTaxExpenseBenefitAtFederalStatutoryIncomeTaxRate	31000000	USD
	us-gaap	Income Tax Reconciliation Income Tax Expense Benefit At Federal Statutory Income Tax Rate IncomeTaxReconciliationIncomeTaxExpenseBenefitAtFederalStatutoryIncomeTaxRate	64000000	USD
	us-gaap	Income Tax Reconciliation Income Tax Expense Benefit At Federal Statutory Income Tax Rate IncomeTaxReconciliationIncomeTaxExpenseBenefitAtFederalStatutoryIncomeTaxRate	80000000	USD
CY2019Q3	us-gaap	Income Tax Reconciliation Tax Exempt Income IncomeTaxReconciliationTaxExemptIncome	5000000	USD
CY2018Q3	us-gaap	Income Tax Reconciliation Tax Exempt Income IncomeTaxReconciliationTaxExemptIncome	6000000	USD
	us-gaap	Income Tax Reconciliation Tax Exempt Income IncomeTaxReconciliationTaxExemptIncome	15000000	USD
	us-gaap	Income Tax Reconciliation Tax Exempt Income IncomeTaxReconciliationTaxExemptIncome	18000000	USD
CY2019Q3	us-gaap	Income Tax Reconciliation Tax Contingencies IncomeTaxReconciliationTaxContingencies	1000000	USD
CY2018Q3	us-gaap	Income Tax Reconciliation Tax Contingencies IncomeTaxReconciliationTaxContingencies	-10000000	USD
	us-gaap	Income Tax Reconciliation Tax Contingencies IncomeTaxReconciliationTaxContingencies	1000000	USD
	us-gaap	Income Tax Reconciliation Tax Contingencies IncomeTaxReconciliationTaxContingencies	-16000000	USD
CY2019Q3	us-gaap	Income Tax Reconciliation Prior Year Income Taxes IncomeTaxReconciliationPriorYearIncomeTaxes	-6000000	USD
CY2018Q3	us-gaap	Income Tax Reconciliation Prior Year Income Taxes IncomeTaxReconciliationPriorYearIncomeTaxes	-1000000	USD
	us-gaap	Income Tax Reconciliation Prior Year Income Taxes IncomeTaxReconciliationPriorYearIncomeTaxes	-6000000	USD
	us-gaap	Income Tax Reconciliation Prior Year Income Taxes IncomeTaxReconciliationPriorYearIncomeTaxes	-1000000	USD
CY2019Q3	us-gaap	Income Tax Reconciliation State And Local Income Taxes IncomeTaxReconciliationStateAndLocalIncomeTaxes	0	USD
CY2018Q3	us-gaap	Income Tax Reconciliation State And Local Income Taxes IncomeTaxReconciliationStateAndLocalIncomeTaxes	5000000	USD
	us-gaap	Income Tax Reconciliation State And Local Income Taxes IncomeTaxReconciliationStateAndLocalIncomeTaxes	1000000	USD
	us-gaap	Income Tax Reconciliation State And Local Income Taxes IncomeTaxReconciliationStateAndLocalIncomeTaxes	6000000	USD
CY2019Q3	us-gaap	Income Tax Reconciliation Foreign Income Tax Rate Differential IncomeTaxReconciliationForeignIncomeTaxRateDifferential	6000000	USD
CY2018Q3	us-gaap	Income Tax Reconciliation Foreign Income Tax Rate Differential IncomeTaxReconciliationForeignIncomeTaxRateDifferential	1000000	USD
	us-gaap	Income Tax Reconciliation Foreign Income Tax Rate Differential IncomeTaxReconciliationForeignIncomeTaxRateDifferential	11000000	USD
	us-gaap	Income Tax Reconciliation Foreign Income Tax Rate Differential IncomeTaxReconciliationForeignIncomeTaxRateDifferential	4000000	USD
CY2019Q3	ago	Effective Income Tax Rate Reconciliation Taxeson Reinsurance Amount EffectiveIncomeTaxRateReconciliationTaxesonReinsuranceAmount	5000000	USD
CY2018Q3	ago	Effective Income Tax Rate Reconciliation Taxeson Reinsurance Amount EffectiveIncomeTaxRateReconciliationTaxesonReinsuranceAmount	1000000	USD
	ago	Effective Income Tax Rate Reconciliation Taxeson Reinsurance Amount EffectiveIncomeTaxRateReconciliationTaxesonReinsuranceAmount	9000000	USD
	ago	Effective Income Tax Rate Reconciliation Taxeson Reinsurance Amount EffectiveIncomeTaxRateReconciliationTaxesonReinsuranceAmount	0	USD
CY2019Q3	us-gaap	Tax Cuts And Jobs Act Of2017 Incomplete Accounting Provisional Income Tax Expense Benefit TaxCutsAndJobsActOf2017IncompleteAccountingProvisionalIncomeTaxExpenseBenefit	0	USD
CY2018Q3	us-gaap	Tax Cuts And Jobs Act Of2017 Incomplete Accounting Provisional Income Tax Expense Benefit TaxCutsAndJobsActOf2017IncompleteAccountingProvisionalIncomeTaxExpenseBenefit	-4000000	USD
	us-gaap	Tax Cuts And Jobs Act Of2017 Incomplete Accounting Provisional Income Tax Expense Benefit TaxCutsAndJobsActOf2017IncompleteAccountingProvisionalIncomeTaxExpenseBenefit	0	USD
	us-gaap	Tax Cuts And Jobs Act Of2017 Incomplete Accounting Provisional Income Tax Expense Benefit TaxCutsAndJobsActOf2017IncompleteAccountingProvisionalIncomeTaxExpenseBenefit	-4000000	USD
CY2019Q3	ago	Effective Income Tax Rate Reconciliation Nondeductible Expense Deferred Compensation Amount EffectiveIncomeTaxRateReconciliationNondeductibleExpenseDeferredCompensationAmount	-1000000	USD
CY2018Q3	ago	Effective Income Tax Rate Reconciliation Nondeductible Expense Deferred Compensation Amount EffectiveIncomeTaxRateReconciliationNondeductibleExpenseDeferredCompensationAmount	-1000000	USD
	ago	Effective Income Tax Rate Reconciliation Nondeductible Expense Deferred Compensation Amount EffectiveIncomeTaxRateReconciliationNondeductibleExpenseDeferredCompensationAmount	-3000000	USD
	ago	Effective Income Tax Rate Reconciliation Nondeductible Expense Deferred Compensation Amount EffectiveIncomeTaxRateReconciliationNondeductibleExpenseDeferredCompensationAmount	-2000000	USD
CY2019Q3	us-gaap	Income Tax Reconciliation Other Adjustments IncomeTaxReconciliationOtherAdjustments	0	USD
CY2018Q3	us-gaap	Income Tax Reconciliation Other Adjustments IncomeTaxReconciliationOtherAdjustments	-2000000	USD
	us-gaap	Income Tax Reconciliation Other Adjustments IncomeTaxReconciliationOtherAdjustments	-1000000	USD
	us-gaap	Income Tax Reconciliation Other Adjustments IncomeTaxReconciliationOtherAdjustments	-3000000	USD
CY2019Q3	us-gaap	Income Tax Expense Benefit IncomeTaxExpenseBenefit	17000000	USD
CY2018Q3	us-gaap	Income Tax Expense Benefit IncomeTaxExpenseBenefit	14000000	USD
	us-gaap	Income Tax Expense Benefit IncomeTaxExpenseBenefit	61000000	USD
	us-gaap	Income Tax Expense Benefit IncomeTaxExpenseBenefit	46000000	USD
CY2019Q3	us-gaap	Effective Income Tax Rate Continuing Operations EffectiveIncomeTaxRateContinuingOperations	0.192
CY2018Q3	us-gaap	Effective Income Tax Rate Continuing Operations EffectiveIncomeTaxRateContinuingOperations	0.083
	us-gaap	Effective Income Tax Rate Continuing Operations EffectiveIncomeTaxRateContinuingOperations	0.186
	us-gaap	Effective Income Tax Rate Continuing Operations EffectiveIncomeTaxRateContinuingOperations	0.097
CY2019Q3	us-gaap	Income Loss From Continuing Operations Before Income Taxes Extraordinary Items Noncontrolling Interest IncomeLossFromContinuingOperationsBeforeIncomeTaxesExtraordinaryItemsNoncontrollingInterest	86000000	USD
CY2018Q3	us-gaap	Income Loss From Continuing Operations Before Income Taxes Extraordinary Items Noncontrolling Interest IncomeLossFromContinuingOperationsBeforeIncomeTaxesExtraordinaryItemsNoncontrollingInterest	175000000	USD
	us-gaap	Income Loss From Continuing Operations Before Income Taxes Extraordinary Items Noncontrolling Interest IncomeLossFromContinuingOperationsBeforeIncomeTaxesExtraordinaryItemsNoncontrollingInterest	326000000	USD
	us-gaap	Income Loss From Continuing Operations Before Income Taxes Extraordinary Items Noncontrolling Interest IncomeLossFromContinuingOperationsBeforeIncomeTaxesExtraordinaryItemsNoncontrollingInterest	479000000	USD
CY2019Q3	us-gaap	Revenues Revenues	206000000	USD
CY2018Q3	us-gaap	Revenues Revenues	275000000	USD
	us-gaap	Revenues Revenues	667000000	USD
	us-gaap	Revenues Revenues	788000000	USD
CY2019Q3	us-gaap	Deferred Tax Assets Liabilities Net Noncurrent DeferredTaxAssetsLiabilitiesNetNoncurrent	-24000000	USD
CY2018Q4	us-gaap	Deferred Tax Assets Liabilities Net Noncurrent DeferredTaxAssetsLiabilitiesNetNoncurrent	68000000	USD
CY2019Q3	us-gaap	Deferred Tax Assets Liabilities Net Current DeferredTaxAssetsLiabilitiesNetCurrent	14000000	USD
CY2018Q4	us-gaap	Deferred Tax Assets Liabilities Net Current DeferredTaxAssetsLiabilitiesNetCurrent	22000000	USD
	ago	Tax Cutsand Jobs Actof2017 Incomplete Accounting Transition Taxfor Accumulated Foreign Earnings Tax Credit Realized TaxCutsandJobsActof2017IncompleteAccountingTransitionTaxforAccumulatedForeignEarningsTaxCreditRealized	23000000	USD
CY2019Q3	us-gaap	Tax Credit Carryforward Valuation Allowance TaxCreditCarryforwardValuationAllowance	36000000	USD
	ago	Deferred Tax Assets Realization Assessment Period For Which Cumulative Operating Income Considered DeferredTaxAssetsRealizationAssessmentPeriodForWhichCumulativeOperatingIncomeConsidered	P3Y
	us-gaap	Unrecognized Tax Benefits Income Tax Penalties And Interest Expense UnrecognizedTaxBenefitsIncomeTaxPenaltiesAndInterestExpense	700000	USD
CY2018	us-gaap	Unrecognized Tax Benefits Income Tax Penalties And Interest Expense UnrecognizedTaxBenefitsIncomeTaxPenaltiesAndInterestExpense	1000000	USD
CY2019Q3	us-gaap	Unrecognized Tax Benefits Interest On Income Taxes Accrued UnrecognizedTaxBenefitsInterestOnIncomeTaxesAccrued	1000000	USD
CY2018Q4	us-gaap	Unrecognized Tax Benefits Interest On Income Taxes Accrued UnrecognizedTaxBenefitsInterestOnIncomeTaxesAccrued	2000000	USD
CY2019Q3	us-gaap	Direct Premiums Written DirectPremiumsWritten	67000000	USD
CY2018Q3	us-gaap	Direct Premiums Written DirectPremiumsWritten	57000000	USD
	us-gaap	Direct Premiums Written DirectPremiumsWritten	156000000	USD
	us-gaap	Direct Premiums Written DirectPremiumsWritten	192000000	USD
CY2019Q3	us-gaap	Assumed Premiums Written AssumedPremiumsWritten	2000000	USD
CY2018Q3	us-gaap	Assumed Premiums Written AssumedPremiumsWritten	-7000000	USD
	us-gaap	Assumed Premiums Written AssumedPremiumsWritten	3000000	USD
	us-gaap	Assumed Premiums Written AssumedPremiumsWritten	324000000	USD
CY2019Q3	us-gaap	Ceded Premiums Written CededPremiumsWritten	1000000	USD
CY2018Q3	us-gaap	Ceded Premiums Written CededPremiumsWritten	-1000000	USD
	us-gaap	Ceded Premiums Written CededPremiumsWritten	-12000000	USD
	us-gaap	Ceded Premiums Written CededPremiumsWritten	-14000000	USD
CY2019Q3	us-gaap	Premiums Written Net PremiumsWrittenNet	68000000	USD
CY2018Q3	us-gaap	Premiums Written Net PremiumsWrittenNet	51000000	USD
	us-gaap	Premiums Written Net PremiumsWrittenNet	171000000	USD
	us-gaap	Premiums Written Net PremiumsWrittenNet	530000000	USD
CY2019Q3	us-gaap	Direct Premiums Earned DirectPremiumsEarned	113000000	USD
CY2018Q3	us-gaap	Direct Premiums Earned DirectPremiumsEarned	127000000	USD
	us-gaap	Direct Premiums Earned DirectPremiumsEarned	317000000	USD
	us-gaap	Direct Premiums Earned DirectPremiumsEarned	400000000	USD
CY2019Q3	us-gaap	Assumed Premiums Earned AssumedPremiumsEarned	12000000	USD
CY2018Q3	us-gaap	Assumed Premiums Earned AssumedPremiumsEarned	19000000	USD
	us-gaap	Assumed Premiums Earned AssumedPremiumsEarned	42000000	USD
	us-gaap	Assumed Premiums Earned AssumedPremiumsEarned	33000000	USD
CY2019Q3	us-gaap	Ceded Premiums Earned CededPremiumsEarned	2000000	USD
CY2018Q3	us-gaap	Ceded Premiums Earned CededPremiumsEarned	4000000	USD
	us-gaap	Ceded Premiums Earned CededPremiumsEarned	6000000	USD
	us-gaap	Ceded Premiums Earned CededPremiumsEarned	10000000	USD
CY2019Q3	us-gaap	Premiums Earned Net PremiumsEarnedNet	123000000	USD
CY2018Q3	us-gaap	Premiums Earned Net PremiumsEarnedNet	142000000	USD
	us-gaap	Premiums Earned Net PremiumsEarnedNet	353000000	USD
	us-gaap	Premiums Earned Net PremiumsEarnedNet	423000000	USD
CY2019Q3	us-gaap	Policyholder Benefits And Claims Incurred Gross PolicyholderBenefitsAndClaimsIncurredGross	28000000	USD
CY2018Q3	us-gaap	Policyholder Benefits And Claims Incurred Gross PolicyholderBenefitsAndClaimsIncurredGross	18000000	USD
	us-gaap	Policyholder Benefits And Claims Incurred Gross PolicyholderBenefitsAndClaimsIncurredGross	82000000	USD
	us-gaap	Policyholder Benefits And Claims Incurred Gross PolicyholderBenefitsAndClaimsIncurredGross	53000000	USD
CY2019Q3	us-gaap	Reinsurance Effect On Claims And Benefits Incurred Amount Assumed ReinsuranceEffectOnClaimsAndBenefitsIncurredAmountAssumed	2000000	USD
CY2018Q3	us-gaap	Reinsurance Effect On Claims And Benefits Incurred Amount Assumed ReinsuranceEffectOnClaimsAndBenefitsIncurredAmountAssumed	1000000	USD
	us-gaap	Reinsurance Effect On Claims And Benefits Incurred Amount Assumed ReinsuranceEffectOnClaimsAndBenefitsIncurredAmountAssumed	4000000	USD
	us-gaap	Reinsurance Effect On Claims And Benefits Incurred Amount Assumed ReinsuranceEffectOnClaimsAndBenefitsIncurredAmountAssumed	-7000000	USD
CY2019Q3	us-gaap	Reinsurance Effect On Claims And Benefits Incurred Amount Ceded ReinsuranceEffectOnClaimsAndBenefitsIncurredAmountCeded	0	USD
CY2018Q3	us-gaap	Reinsurance Effect On Claims And Benefits Incurred Amount Ceded ReinsuranceEffectOnClaimsAndBenefitsIncurredAmountCeded	2000000	USD
	us-gaap	Reinsurance Effect On Claims And Benefits Incurred Amount Ceded ReinsuranceEffectOnClaimsAndBenefitsIncurredAmountCeded	11000000	USD
	us-gaap	Reinsurance Effect On Claims And Benefits Incurred Amount Ceded ReinsuranceEffectOnClaimsAndBenefitsIncurredAmountCeded	3000000	USD
CY2019Q3	us-gaap	Policyholder Benefits And Claims Incurred Net PolicyholderBenefitsAndClaimsIncurredNet	30000000	USD
CY2018Q3	us-gaap	Policyholder Benefits And Claims Incurred Net PolicyholderBenefitsAndClaimsIncurredNet	17000000	USD
	us-gaap	Policyholder Benefits And Claims Incurred Net PolicyholderBenefitsAndClaimsIncurredNet	75000000	USD
	us-gaap	Policyholder Benefits And Claims Incurred Net PolicyholderBenefitsAndClaimsIncurredNet	43000000	USD
CY2019Q3	ago	Ceded Premium Payable Netof Commissions CededPremiumPayableNetofCommissions	19000000	USD
CY2018Q4	ago	Ceded Premium Payable Netof Commissions CededPremiumPayableNetofCommissions	26000000	USD
CY2019Q3	ago	Ceded Expected Loss And Loss Adjustment Expense CededExpectedLossAndLossAdjustmentExpense	14000000	USD
CY2018Q4	ago	Ceded Expected Loss And Loss Adjustment Expense CededExpectedLossAndLossAdjustmentExpense	14000000	USD
CY2019Q3	ago	Insured Financial Obligations Ceded Par Outstanding InsuredFinancialObligationsCededParOutstanding	1343000000	USD
CY2018Q4	ago	Insured Financial Obligations Ceded Par Outstanding InsuredFinancialObligationsCededParOutstanding	2389000000	USD
CY2019Q3	ago	Non Financial Guaranty Exposure Ceded Par Outstanding NonFinancialGuarantyExposureCededParOutstanding	275000000	USD
CY2018Q4	ago	Non Financial Guaranty Exposure Ceded Par Outstanding NonFinancialGuarantyExposureCededParOutstanding	239000000	USD
CY2019Q3	ago	Increase Decrease In Unearned Premiums Due To Commutations IncreaseDecreaseInUnearnedPremiumsDueToCommutations	0	USD
CY2018Q3	ago	Increase Decrease In Unearned Premiums Due To Commutations IncreaseDecreaseInUnearnedPremiumsDueToCommutations	4000000	USD
	ago	Increase Decrease In Unearned Premiums Due To Commutations IncreaseDecreaseInUnearnedPremiumsDueToCommutations	15000000	USD
	ago	Increase Decrease In Unearned Premiums Due To Commutations IncreaseDecreaseInUnearnedPremiumsDueToCommutations	64000000	USD
CY2019Q3	ago	Increase Decrease In Net Par Due To Commutations IncreaseDecreaseInNetParDueToCommutations	0	USD
CY2018Q3	ago	Increase Decrease In Net Par Due To Commutations IncreaseDecreaseInNetParDueToCommutations	224000000	USD
	ago	Increase Decrease In Net Par Due To Commutations IncreaseDecreaseInNetParDueToCommutations	1069000000	USD
	ago	Increase Decrease In Net Par Due To Commutations IncreaseDecreaseInNetParDueToCommutations	1457000000	USD
CY2019Q3	ago	Gain Loss From Commutations GainLossFromCommutations	0	USD
CY2018Q3	ago	Gain Loss From Commutations GainLossFromCommutations	1000000	USD
	ago	Gain Loss From Commutations GainLossFromCommutations	1000000	USD
	ago	Gain Loss From Commutations GainLossFromCommutations	-16000000	USD
	ago	Operating Lease Numberof Square Feet OperatingLeaseNumberofSquareFeet	103500	sqft
CY2019Q3	us-gaap	Lessee Operating Lease Renewal Term LesseeOperatingLeaseRenewalTerm	P5Y
	ago	Lessee Operating Lease Leases Excludedfrom Recognitionof Topic842 Initial Term LesseeOperatingLeaseLeasesExcludedfromRecognitionofTopic842InitialTerm	P12M
CY2019Q1	us-gaap	Operating Lease Liability OperatingLeaseLiability	95000000	USD
CY2019Q1	us-gaap	Operating Lease Right Of Use Asset OperatingLeaseRightOfUseAsset	69000000	USD
CY2019Q1	ago	Derecognized Deferred Rent And Lease Incentive Liabilities DerecognizedDeferredRentAndLeaseIncentiveLiabilities	26000000	USD
CY2019Q3	us-gaap	Operating Lease Right Of Use Asset OperatingLeaseRightOfUseAsset	65000000	USD
CY2019Q3	us-gaap	Operating Lease Liability OperatingLeaseLiability	90000000	USD
CY2019Q3	us-gaap	Lease Cost LeaseCost	3000000	USD
	us-gaap	Lease Cost LeaseCost	7000000	USD
CY2019Q3	us-gaap	Operating Lease Payments OperatingLeasePayments	3000000	USD
	us-gaap	Operating Lease Payments OperatingLeasePayments	7000000	USD
CY2019Q3	us-gaap	Operating Lease Weighted Average Remaining Lease Term1 OperatingLeaseWeightedAverageRemainingLeaseTerm1	P12Y
CY2019Q3	us-gaap	Operating Lease Weighted Average Discount Rate Percent OperatingLeaseWeightedAverageDiscountRatePercent	0.030
CY2019Q3	us-gaap	Lessee Operating Lease Liability Payments Remainder Of Fiscal Year LesseeOperatingLeaseLiabilityPaymentsRemainderOfFiscalYear	2000000	USD
CY2019Q3	us-gaap	Lessee Operating Lease Liability Payments Due Year Two LesseeOperatingLeaseLiabilityPaymentsDueYearTwo	9000000	USD
CY2019Q3	us-gaap	Lessee Operating Lease Liability Payments Due Year Three LesseeOperatingLeaseLiabilityPaymentsDueYearThree	8000000	USD
CY2019Q3	us-gaap	Lessee Operating Lease Liability Payments Due Year Four LesseeOperatingLeaseLiabilityPaymentsDueYearFour	8000000	USD
CY2019Q3	us-gaap	Lessee Operating Lease Liability Payments Due Year Five LesseeOperatingLeaseLiabilityPaymentsDueYearFive	9000000	USD
CY2019Q3	us-gaap	Lessee Operating Lease Liability Payments Due After Year Five LesseeOperatingLeaseLiabilityPaymentsDueAfterYearFive	72000000	USD
CY2019Q3	us-gaap	Lessee Operating Lease Liability Payments Due LesseeOperatingLeaseLiabilityPaymentsDue	108000000	USD
CY2019Q3	us-gaap	Lessee Operating Lease Liability Undiscounted Excess Amount LesseeOperatingLeaseLiabilityUndiscountedExcessAmount	18000000	USD
CY2019Q3	us-gaap	Operating Lease Liability OperatingLeaseLiability	90000000	USD
CY2018Q4	us-gaap	Operating Leases Future Minimum Payments Due Current OperatingLeasesFutureMinimumPaymentsDueCurrent	9000000	USD
CY2018Q4	us-gaap	Operating Leases Future Minimum Payments Due In Two Years OperatingLeasesFutureMinimumPaymentsDueInTwoYears	9000000	USD
CY2018Q4	us-gaap	Operating Leases Future Minimum Payments Due In Three Years OperatingLeasesFutureMinimumPaymentsDueInThreeYears	8000000	USD
CY2018Q4	us-gaap	Operating Leases Future Minimum Payments Due In Four Years OperatingLeasesFutureMinimumPaymentsDueInFourYears	8000000	USD
CY2018Q4	us-gaap	Operating Leases Future Minimum Payments Due In Five Years OperatingLeasesFutureMinimumPaymentsDueInFiveYears	9000000	USD
CY2018Q4	us-gaap	Operating Leases Future Minimum Payments Due Thereafter OperatingLeasesFutureMinimumPaymentsDueThereafter	72000000	USD
CY2019Q3	us-gaap	Net Income Loss NetIncomeLoss	69000000	USD
CY2018Q3	us-gaap	Net Income Loss NetIncomeLoss	161000000	USD
	us-gaap	Net Income Loss NetIncomeLoss	265000000	USD
	us-gaap	Net Income Loss NetIncomeLoss	433000000	USD
CY2019Q3	us-gaap	Participating Securities Distributed And Undistributed Earnings Loss Basic ParticipatingSecuritiesDistributedAndUndistributedEarningsLossBasic	0	USD
CY2018Q3	us-gaap	Participating Securities Distributed And Undistributed Earnings Loss Basic ParticipatingSecuritiesDistributedAndUndistributedEarningsLossBasic	1000000	USD
	us-gaap	Participating Securities Distributed And Undistributed Earnings Loss Basic ParticipatingSecuritiesDistributedAndUndistributedEarningsLossBasic	0	USD
	us-gaap	Participating Securities Distributed And Undistributed Earnings Loss Basic ParticipatingSecuritiesDistributedAndUndistributedEarningsLossBasic	1000000	USD
CY2019Q3	us-gaap	Net Income Loss Available To Common Stockholders Basic NetIncomeLossAvailableToCommonStockholdersBasic	69000000	USD
CY2018Q3	us-gaap	Net Income Loss Available To Common Stockholders Basic NetIncomeLossAvailableToCommonStockholdersBasic	160000000	USD
	us-gaap	Net Income Loss Available To Common Stockholders Basic NetIncomeLossAvailableToCommonStockholdersBasic	265000000	USD
	us-gaap	Net Income Loss Available To Common Stockholders Basic NetIncomeLossAvailableToCommonStockholdersBasic	432000000	USD
CY2019Q3	us-gaap	Weighted Average Number Of Shares Outstanding Basic WeightedAverageNumberOfSharesOutstandingBasic	98200000	shares
CY2018Q3	us-gaap	Weighted Average Number Of Shares Outstanding Basic WeightedAverageNumberOfSharesOutstandingBasic	108000000.0	shares
	us-gaap	Weighted Average Number Of Shares Outstanding Basic WeightedAverageNumberOfSharesOutstandingBasic	100800000	shares
	us-gaap	Weighted Average Number Of Shares Outstanding Basic WeightedAverageNumberOfSharesOutstandingBasic	111600000	shares
CY2019Q3	us-gaap	Earnings Per Share Basic EarningsPerShareBasic	0.71
CY2018Q3	us-gaap	Earnings Per Share Basic EarningsPerShareBasic	1.48
	us-gaap	Earnings Per Share Basic EarningsPerShareBasic	2.63
	us-gaap	Earnings Per Share Basic EarningsPerShareBasic	3.87
CY2019Q3	us-gaap	Net Income Loss Available To Common Stockholders Basic NetIncomeLossAvailableToCommonStockholdersBasic	69000000	USD
CY2018Q3	us-gaap	Net Income Loss Available To Common Stockholders Basic NetIncomeLossAvailableToCommonStockholdersBasic	160000000	USD
	us-gaap	Net Income Loss Available To Common Stockholders Basic NetIncomeLossAvailableToCommonStockholdersBasic	265000000	USD
	us-gaap	Net Income Loss Available To Common Stockholders Basic NetIncomeLossAvailableToCommonStockholdersBasic	432000000	USD
CY2019Q3	us-gaap	Undistributed Earnings Loss Allocated To Participating Securities Diluted UndistributedEarningsLossAllocatedToParticipatingSecuritiesDiluted	0	USD
CY2018Q3	us-gaap	Undistributed Earnings Loss Allocated To Participating Securities Diluted UndistributedEarningsLossAllocatedToParticipatingSecuritiesDiluted	0	USD
	us-gaap	Undistributed Earnings Loss Allocated To Participating Securities Diluted UndistributedEarningsLossAllocatedToParticipatingSecuritiesDiluted	0	USD
	us-gaap	Undistributed Earnings Loss Allocated To Participating Securities Diluted UndistributedEarningsLossAllocatedToParticipatingSecuritiesDiluted	0	USD
CY2019Q3	us-gaap	Net Income Loss Available To Common Stockholders Diluted NetIncomeLossAvailableToCommonStockholdersDiluted	69000000	USD
CY2018Q3	us-gaap	Net Income Loss Available To Common Stockholders Diluted NetIncomeLossAvailableToCommonStockholdersDiluted	160000000	USD
	us-gaap	Net Income Loss Available To Common Stockholders Diluted NetIncomeLossAvailableToCommonStockholdersDiluted	265000000	USD
	us-gaap	Net Income Loss Available To Common Stockholders Diluted NetIncomeLossAvailableToCommonStockholdersDiluted	432000000	USD
CY2019Q3	us-gaap	Weighted Average Number Of Shares Outstanding Basic WeightedAverageNumberOfSharesOutstandingBasic	98200000	shares
CY2018Q3	us-gaap	Weighted Average Number Of Shares Outstanding Basic WeightedAverageNumberOfSharesOutstandingBasic	108000000.0	shares
	us-gaap	Weighted Average Number Of Shares Outstanding Basic WeightedAverageNumberOfSharesOutstandingBasic	100800000	shares
	us-gaap	Weighted Average Number Of Shares Outstanding Basic WeightedAverageNumberOfSharesOutstandingBasic	111600000	shares
CY2019Q3	us-gaap	Incremental Common Shares Attributable To Share Based Payment Arrangements IncrementalCommonSharesAttributableToShareBasedPaymentArrangements	700000	shares
CY2018Q3	us-gaap	Incremental Common Shares Attributable To Share Based Payment Arrangements IncrementalCommonSharesAttributableToShareBasedPaymentArrangements	1300000	shares
	us-gaap	Incremental Common Shares Attributable To Share Based Payment Arrangements IncrementalCommonSharesAttributableToShareBasedPaymentArrangements	800000	shares
	us-gaap	Incremental Common Shares Attributable To Share Based Payment Arrangements IncrementalCommonSharesAttributableToShareBasedPaymentArrangements	1300000	shares
CY2019Q3	us-gaap	Weighted Average Number Of Diluted Shares Outstanding WeightedAverageNumberOfDilutedSharesOutstanding	98900000	shares
CY2018Q3	us-gaap	Weighted Average Number Of Diluted Shares Outstanding WeightedAverageNumberOfDilutedSharesOutstanding	109300000	shares
	us-gaap	Weighted Average Number Of Diluted Shares Outstanding WeightedAverageNumberOfDilutedSharesOutstanding	101600000	shares
	us-gaap	Weighted Average Number Of Diluted Shares Outstanding WeightedAverageNumberOfDilutedSharesOutstanding	112900000	shares
CY2019Q3	us-gaap	Earnings Per Share Diluted EarningsPerShareDiluted	0.70
CY2018Q3	us-gaap	Earnings Per Share Diluted EarningsPerShareDiluted	1.47
	us-gaap	Earnings Per Share Diluted EarningsPerShareDiluted	2.61
	us-gaap	Earnings Per Share Diluted EarningsPerShareDiluted	3.83
CY2019Q3	us-gaap	Antidilutive Securities Excluded From Computation Of Earnings Per Share Amount AntidilutiveSecuritiesExcludedFromComputationOfEarningsPerShareAmount	0	shares
CY2018Q3	us-gaap	Antidilutive Securities Excluded From Computation Of Earnings Per Share Amount AntidilutiveSecuritiesExcludedFromComputationOfEarningsPerShareAmount	0	shares
	us-gaap	Antidilutive Securities Excluded From Computation Of Earnings Per Share Amount AntidilutiveSecuritiesExcludedFromComputationOfEarningsPerShareAmount	0	shares
	us-gaap	Antidilutive Securities Excluded From Computation Of Earnings Per Share Amount AntidilutiveSecuritiesExcludedFromComputationOfEarningsPerShareAmount	100000	shares
CY2019Q3	us-gaap	Other Comprehensive Income Loss Before Reclassifications Net Of Tax OtherComprehensiveIncomeLossBeforeReclassificationsNetOfTax	34000000	USD
CY2019Q3	us-gaap	Other Comprehensive Income Loss Net Of Tax OtherComprehensiveIncomeLossNetOfTax	24000000	USD
CY2018Q3	us-gaap	Other Comprehensive Income Loss Before Reclassifications Net Of Tax OtherComprehensiveIncomeLossBeforeReclassificationsNetOfTax	-83000000	USD
CY2018Q3	us-gaap	Other Comprehensive Income Loss Net Of Tax OtherComprehensiveIncomeLossNetOfTax	-74000000	USD
	us-gaap	Other Comprehensive Income Loss Before Reclassifications Net Of Tax OtherComprehensiveIncomeLossBeforeReclassificationsNetOfTax	237000000	USD
	us-gaap	Other Comprehensive Income Loss Net Of Tax OtherComprehensiveIncomeLossNetOfTax	226000000	USD
CY2017Q4	us-gaap	Cumulative Effect Of New Accounting Principle In Period Of Adoption CumulativeEffectOfNewAccountingPrincipleInPeriodOfAdoption	-32000000	USD
	us-gaap	Other Comprehensive Income Loss Before Reclassifications Net Of Tax OtherComprehensiveIncomeLossBeforeReclassificationsNetOfTax	-278000000	USD
	us-gaap	Other Comprehensive Income Loss Net Of Tax OtherComprehensiveIncomeLossNetOfTax	-262000000	USD
	us-gaap	Subsidiary Of Limited Liability Company Or Limited Partnership Ownership Interest SubsidiaryOfLimitedLiabilityCompanyOrLimitedPartnershipOwnershipInterest	1
CY2019Q3	us-gaap	Investments And Cash InvestmentsAndCash	10705000000	USD
CY2019Q3	us-gaap	Investments In Affiliates Subsidiaries Associates And Joint Ventures InvestmentsInAffiliatesSubsidiariesAssociatesAndJointVentures	0	USD
CY2019Q3	us-gaap	Premiums Receivable At Carrying Value PremiumsReceivableAtCarryingValue	844000000	USD
CY2019Q3	us-gaap	Deferred Policy Acquisition Costs DeferredPolicyAcquisitionCosts	107000000	USD
CY2019Q3	us-gaap	Due From Affiliates DueFromAffiliates	0	USD
CY2019Q3	us-gaap	Variable Interest Entity Consolidated Carrying Amount Assets VariableInterestEntityConsolidatedCarryingAmountAssets	469000000	USD
CY2019Q3	us-gaap	Dividends Receivable DividendsReceivable	0	USD
CY2019Q3	ago	Other Assets Consolidating OtherAssetsConsolidating	1242000000	USD
CY2019Q3	us-gaap	Assets Assets	13367000000	USD
CY2019Q3	us-gaap	Unearned Premiums UnearnedPremiums	3334000000	USD
CY2019Q3	us-gaap	Liability For Claims And Claims Adjustment Expense LiabilityForClaimsAndClaimsAdjustmentExpense	1007000000	USD
CY2019Q3	us-gaap	Long Term Debt LongTermDebt	1234000000	USD
CY2019Q3	us-gaap	Due To Affiliate Current And Noncurrent DueToAffiliateCurrentAndNoncurrent	0	USD
CY2019Q3	us-gaap	Credit Risk Derivative Liabilities At Fair Value CreditRiskDerivativeLiabilitiesAtFairValue	214000000	USD
CY2019Q3	us-gaap	Variable Interest Entity Consolidated Carrying Amount Liabilities VariableInterestEntityConsolidatedCarryingAmountLiabilities	493000000	USD
CY2019Q3	us-gaap	Dividends Payable Current And Noncurrent DividendsPayableCurrentAndNoncurrent	0	USD
CY2019Q3	ago	Other Liabilities Consolidating OtherLiabilitiesConsolidating	433000000	USD
CY2019Q3	us-gaap	Liabilities Liabilities	6715000000	USD
CY2019Q3	us-gaap	Stockholders Equity StockholdersEquity	6652000000	USD
CY2019Q3	us-gaap	Minority Interest MinorityInterest	0	USD
CY2019Q3	us-gaap	Stockholders Equity Including Portion Attributable To Noncontrolling Interest StockholdersEquityIncludingPortionAttributableToNoncontrollingInterest	6652000000	USD
CY2019Q3	us-gaap	Liabilities And Stockholders Equity LiabilitiesAndStockholdersEquity	13367000000	USD
CY2018Q4	us-gaap	Investments And Cash InvestmentsAndCash	10977000000	USD
CY2018Q4	us-gaap	Investments In Affiliates Subsidiaries Associates And Joint Ventures InvestmentsInAffiliatesSubsidiariesAssociatesAndJointVentures	0	USD
CY2018Q4	us-gaap	Premiums Receivable At Carrying Value PremiumsReceivableAtCarryingValue	904000000	USD
CY2018Q4	us-gaap	Deferred Policy Acquisition Costs DeferredPolicyAcquisitionCosts	105000000	USD
CY2018Q4	us-gaap	Deferred Tax Assets Net DeferredTaxAssetsNet	68000000	USD
CY2018Q4	us-gaap	Due From Affiliates DueFromAffiliates	0	USD
CY2018Q4	us-gaap	Variable Interest Entity Consolidated Carrying Amount Assets VariableInterestEntityConsolidatedCarryingAmountAssets	569000000	USD
CY2018Q4	us-gaap	Dividends Receivable DividendsReceivable	0	USD
CY2018Q4	ago	Other Assets Consolidating OtherAssetsConsolidating	980000000	USD
CY2018Q4	us-gaap	Assets Assets	13603000000	USD
CY2018Q4	us-gaap	Unearned Premiums UnearnedPremiums	3512000000	USD
CY2018Q4	us-gaap	Liability For Claims And Claims Adjustment Expense LiabilityForClaimsAndClaimsAdjustmentExpense	1177000000	USD
CY2018Q4	us-gaap	Long Term Debt LongTermDebt	1233000000	USD
CY2018Q4	us-gaap	Due To Affiliate Current And Noncurrent DueToAffiliateCurrentAndNoncurrent	0	USD
CY2018Q4	us-gaap	Credit Risk Derivative Liabilities At Fair Value CreditRiskDerivativeLiabilitiesAtFairValue	209000000	USD
CY2018Q4	us-gaap	Deferred Tax Liabilities DeferredTaxLiabilities	0	USD
CY2018Q4	us-gaap	Variable Interest Entity Consolidated Carrying Amount Liabilities VariableInterestEntityConsolidatedCarryingAmountLiabilities	619000000	USD
CY2018Q4	us-gaap	Dividends Payable Current And Noncurrent DividendsPayableCurrentAndNoncurrent	0	USD
CY2018Q4	ago	Other Liabilities Consolidating OtherLiabilitiesConsolidating	298000000	USD
CY2018Q4	us-gaap	Liabilities Liabilities	7048000000	USD
CY2018Q4	us-gaap	Stockholders Equity StockholdersEquity	6555000000	USD
CY2018Q4	us-gaap	Minority Interest MinorityInterest	0	USD
CY2018Q4	us-gaap	Stockholders Equity Including Portion Attributable To Noncontrolling Interest StockholdersEquityIncludingPortionAttributableToNoncontrollingInterest	6555000000	USD
CY2018Q4	us-gaap	Liabilities And Stockholders Equity LiabilitiesAndStockholdersEquity	13603000000	USD
CY2019Q3	us-gaap	Premiums Earned Net PremiumsEarnedNet	123000000	USD
CY2019Q3	us-gaap	Net Investment Income NetInvestmentIncome	88000000	USD
CY2019Q3	us-gaap	Realized Investment Gains Losses RealizedInvestmentGainsLosses	16000000	USD
CY2019Q3	us-gaap	Derivative Gain Loss On Derivative Net DerivativeGainLossOnDerivativeNet	5000000	USD
CY2019Q3	ago	Other Income Consolidating OtherIncomeConsolidating	-26000000	USD
CY2019Q3	us-gaap	Revenues Revenues	206000000	USD
CY2019Q3	us-gaap	Policyholder Benefits And Claims Incurred Net PolicyholderBenefitsAndClaimsIncurredNet	30000000	USD
CY2019Q3	us-gaap	Deferred Policy Acquisition Cost Amortization Expense DeferredPolicyAcquisitionCostAmortizationExpense	3000000	USD
CY2019Q3	us-gaap	Interest Expense InterestExpense	22000000	USD
CY2019Q3	us-gaap	Other Cost And Expense Operating OtherCostAndExpenseOperating	65000000	USD
CY2019Q3	us-gaap	Benefits Losses And Expenses BenefitsLossesAndExpenses	120000000	USD
CY2019Q3	us-gaap	Income Loss From Equity Method Investments IncomeLossFromEquityMethodInvestments	0	USD
CY2019Q3	us-gaap	Income Loss From Continuing Operations Before Income Taxes Extraordinary Items Noncontrolling Interest IncomeLossFromContinuingOperationsBeforeIncomeTaxesExtraordinaryItemsNoncontrollingInterest	86000000	USD
CY2019Q3	us-gaap	Income Tax Expense Benefit IncomeTaxExpenseBenefit	17000000	USD
CY2019Q3	us-gaap	Income Loss From Subsidiaries Net Of Tax IncomeLossFromSubsidiariesNetOfTax	0	USD
CY2019Q3	us-gaap	Profit Loss ProfitLoss	69000000	USD
CY2019Q3	us-gaap	Net Income Loss Attributable To Noncontrolling Interest NetIncomeLossAttributableToNoncontrollingInterest	0	USD
CY2019Q3	us-gaap	Net Income Loss NetIncomeLoss	69000000	USD
CY2019Q3	us-gaap	Comprehensive Income Net Of Tax Including Portion Attributable To Noncontrolling Interest ComprehensiveIncomeNetOfTaxIncludingPortionAttributableToNoncontrollingInterest	93000000	USD
	us-gaap	Derivative Gain Loss On Derivative Net DerivativeGainLossOnDerivativeNet	103000000	USD
	ago	Other Income Consolidating OtherIncomeConsolidating	-21000000	USD
CY2018Q3	us-gaap	Premiums Earned Net PremiumsEarnedNet	142000000	USD
CY2018Q3	us-gaap	Net Investment Income NetInvestmentIncome	99000000	USD
CY2018Q3	us-gaap	Realized Investment Gains Losses RealizedInvestmentGainsLosses	-7000000	USD
CY2018Q3	us-gaap	Derivative Gain Loss On Derivative Net DerivativeGainLossOnDerivativeNet	21000000	USD
CY2018Q3	ago	Other Income Consolidating OtherIncomeConsolidating	20000000	USD
CY2018Q3	us-gaap	Revenues Revenues	275000000	USD
CY2018Q3	us-gaap	Policyholder Benefits And Claims Incurred Net PolicyholderBenefitsAndClaimsIncurredNet	17000000	USD
CY2018Q3	us-gaap	Deferred Policy Acquisition Cost Amortization Expense DeferredPolicyAcquisitionCostAmortizationExpense	3000000	USD
CY2018Q3	us-gaap	Interest Expense InterestExpense	23000000	USD
CY2018Q3	us-gaap	Other Cost And Expense Operating OtherCostAndExpenseOperating	56000000	USD
CY2018Q3	us-gaap	Benefits Losses And Expenses BenefitsLossesAndExpenses	99000000	USD
CY2018Q3	us-gaap	Income Loss From Equity Method Investments IncomeLossFromEquityMethodInvestments	-1000000	USD
CY2018Q3	us-gaap	Income Loss From Continuing Operations Before Income Taxes Extraordinary Items Noncontrolling Interest IncomeLossFromContinuingOperationsBeforeIncomeTaxesExtraordinaryItemsNoncontrollingInterest	175000000	USD
CY2018Q3	us-gaap	Income Tax Expense Benefit IncomeTaxExpenseBenefit	14000000	USD
CY2018Q3	us-gaap	Income Loss From Subsidiaries Net Of Tax IncomeLossFromSubsidiariesNetOfTax	0	USD
CY2018Q3	us-gaap	Profit Loss ProfitLoss	161000000	USD
CY2018Q3	us-gaap	Net Income Loss Attributable To Noncontrolling Interest NetIncomeLossAttributableToNoncontrollingInterest	0	USD
CY2018Q3	us-gaap	Net Income Loss NetIncomeLoss	161000000	USD
CY2018Q3	us-gaap	Comprehensive Income Net Of Tax Including Portion Attributable To Noncontrolling Interest ComprehensiveIncomeNetOfTaxIncludingPortionAttributableToNoncontrollingInterest	87000000	USD
	us-gaap	Premiums Earned Net PremiumsEarnedNet	353000000	USD
	us-gaap	Net Investment Income NetInvestmentIncome	296000000	USD
	us-gaap	Realized Investment Gains Losses RealizedInvestmentGainsLosses	12000000	USD
	us-gaap	Derivative Gain Loss On Derivative Net DerivativeGainLossOnDerivativeNet	-25000000	USD
	ago	Other Income Consolidating OtherIncomeConsolidating	31000000	USD
	us-gaap	Revenues Revenues	667000000	USD
	us-gaap	Policyholder Benefits And Claims Incurred Net PolicyholderBenefitsAndClaimsIncurredNet	75000000	USD
	us-gaap	Deferred Policy Acquisition Cost Amortization Expense DeferredPolicyAcquisitionCostAmortizationExpense	13000000	USD
	us-gaap	Interest Expense InterestExpense	67000000	USD
	us-gaap	Other Cost And Expense Operating OtherCostAndExpenseOperating	189000000	USD
	us-gaap	Benefits Losses And Expenses BenefitsLossesAndExpenses	344000000	USD
	us-gaap	Income Loss From Equity Method Investments IncomeLossFromEquityMethodInvestments	3000000	USD
	us-gaap	Income Loss From Continuing Operations Before Income Taxes Extraordinary Items Noncontrolling Interest IncomeLossFromContinuingOperationsBeforeIncomeTaxesExtraordinaryItemsNoncontrollingInterest	326000000	USD
	us-gaap	Income Tax Expense Benefit IncomeTaxExpenseBenefit	61000000	USD
	us-gaap	Income Loss From Subsidiaries Net Of Tax IncomeLossFromSubsidiariesNetOfTax	0	USD
	us-gaap	Profit Loss ProfitLoss	265000000	USD
	us-gaap	Net Income Loss Attributable To Noncontrolling Interest NetIncomeLossAttributableToNoncontrollingInterest	0	USD
	us-gaap	Net Income Loss NetIncomeLoss	265000000	USD
	us-gaap	Comprehensive Income Net Of Tax Including Portion Attributable To Noncontrolling Interest ComprehensiveIncomeNetOfTaxIncludingPortionAttributableToNoncontrollingInterest	491000000	USD
	us-gaap	Premiums Earned Net PremiumsEarnedNet	423000000	USD
	us-gaap	Net Investment Income NetInvestmentIncome	297000000	USD
	us-gaap	Realized Investment Gains Losses RealizedInvestmentGainsLosses	-14000000	USD
	us-gaap	Revenues Revenues	788000000	USD
	us-gaap	Policyholder Benefits And Claims Incurred Net PolicyholderBenefitsAndClaimsIncurredNet	43000000	USD
	us-gaap	Deferred Policy Acquisition Cost Amortization Expense DeferredPolicyAcquisitionCostAmortizationExpense	12000000	USD
	us-gaap	Interest Expense InterestExpense	71000000	USD
	us-gaap	Other Cost And Expense Operating OtherCostAndExpenseOperating	183000000	USD
	us-gaap	Benefits Losses And Expenses BenefitsLossesAndExpenses	309000000	USD
	us-gaap	Income Loss From Equity Method Investments IncomeLossFromEquityMethodInvestments	0	USD
	us-gaap	Income Loss From Continuing Operations Before Income Taxes Extraordinary Items Noncontrolling Interest IncomeLossFromContinuingOperationsBeforeIncomeTaxesExtraordinaryItemsNoncontrollingInterest	479000000	USD
	us-gaap	Income Tax Expense Benefit IncomeTaxExpenseBenefit	46000000	USD
	us-gaap	Income Loss From Subsidiaries Net Of Tax IncomeLossFromSubsidiariesNetOfTax	0	USD
	us-gaap	Profit Loss ProfitLoss	433000000	USD
	us-gaap	Net Income Loss Attributable To Noncontrolling Interest NetIncomeLossAttributableToNoncontrollingInterest	0	USD
	us-gaap	Net Income Loss NetIncomeLoss	433000000	USD
	us-gaap	Comprehensive Income Net Of Tax Including Portion Attributable To Noncontrolling Interest ComprehensiveIncomeNetOfTaxIncludingPortionAttributableToNoncontrollingInterest	171000000	USD
	us-gaap	Net Cash Provided By Used In Operating Activities NetCashProvidedByUsedInOperatingActivities	-365000000	USD
	us-gaap	Payments To Acquire Available For Sale Securities Debt PaymentsToAcquireAvailableForSaleSecuritiesDebt	688000000	USD
	us-gaap	Proceeds From Sale Of Available For Sale Securities Debt ProceedsFromSaleOfAvailableForSaleSecuritiesDebt	1306000000	USD
	us-gaap	Proceeds From Maturities Prepayments And Calls Of Available For Sale Securities ProceedsFromMaturitiesPrepaymentsAndCallsOfAvailableForSaleSecurities	664000000	USD
	us-gaap	Payments To Acquire Short Term Investments PaymentsToAcquireShortTermInvestments	216000000	USD
	us-gaap	Proceeds From Sale Of Short Term Investments ProceedsFromSaleOfShortTermInvestments	2000000	USD
	us-gaap	Proceeds From Maturities Prepayments And Calls Of Shortterm Investments ProceedsFromMaturitiesPrepaymentsAndCallsOfShorttermInvestments	206000000	USD
	us-gaap	Payments For Proceeds From Short Term Investments PaymentsForProceedsFromShortTermInvestments	404000000	USD
	ago	Proceedsfrom Paydownson Financial Guaranty Variable Interest Entities Assets ProceedsfromPaydownsonFinancialGuarantyVariableInterestEntitiesAssets	119000000	USD
	ago	Proceedsfrom Saleof Financial Guaranty Variable Interest Entities Assets ProceedsfromSaleofFinancialGuarantyVariableInterestEntitiesAssets	51000000	USD
	us-gaap	Proceeds From Equity Method Investment Dividends Or Distributions Return Of Capital ProceedsFromEquityMethodInvestmentDividendsOrDistributionsReturnOfCapital	0	USD
	us-gaap	Payments For Proceeds From Other Investing Activities PaymentsForProceedsFromOtherInvestingActivities	-30000000	USD
	us-gaap	Net Cash Provided By Used In Investing Activities NetCashProvidedByUsedInInvestingActivities	1070000000	USD
	us-gaap	Proceeds From Contributions From Affiliates ProceedsFromContributionsFromAffiliates	0	USD
	us-gaap	Payments Of Dividends Common Stock PaymentsOfDividendsCommonStock	56000000	USD
	us-gaap	Payments For Repurchase Of Common Stock PaymentsForRepurchaseOfCommonStock	340000000	USD
	ago	Paydown Of Financial Guaranty Variable Interest Entities Liabilities PaydownOfFinancialGuarantyVariableInterestEntitiesLiabilities	162000000	USD
	us-gaap	Repayments Of Long Term Debt RepaymentsOfLongTermDebt	4000000	USD
	us-gaap	Proceeds From Payments For Other Financing Activities ProceedsFromPaymentsForOtherFinancingActivities	-16000000	USD
	us-gaap	Net Cash Provided By Used In Financing Activities NetCashProvidedByUsedInFinancingActivities	-578000000	USD
	us-gaap	Effect Of Exchange Rate On Cash And Cash Equivalents EffectOfExchangeRateOnCashAndCashEquivalents	-2000000	USD
	ago	Increase Decreasein Cashand Restricted Cash IncreaseDecreaseinCashandRestrictedCash	125000000	USD
CY2018Q4	ago	Cashand Restricted Cash CashandRestrictedCash	104000000	USD
CY2019Q3	ago	Cashand Restricted Cash CashandRestrictedCash	229000000	USD
	us-gaap	Net Cash Provided By Used In Operating Activities NetCashProvidedByUsedInOperatingActivities	352000000	USD
	us-gaap	Payments To Acquire Available For Sale Securities Debt PaymentsToAcquireAvailableForSaleSecuritiesDebt	1478000000	USD
	us-gaap	Proceeds From Sale Of Available For Sale Securities Debt ProceedsFromSaleOfAvailableForSaleSecuritiesDebt	908000000	USD
	us-gaap	Proceeds From Maturities Prepayments And Calls Of Available For Sale Securities ProceedsFromMaturitiesPrepaymentsAndCallsOfAvailableForSaleSecurities	746000000	USD
	us-gaap	Payments To Acquire Short Term Investments PaymentsToAcquireShortTermInvestments	148000000	USD
	us-gaap	Proceeds From Sale Of Short Term Investments ProceedsFromSaleOfShortTermInvestments	1000000	USD
	us-gaap	Proceeds From Maturities Prepayments And Calls Of Shortterm Investments ProceedsFromMaturitiesPrepaymentsAndCallsOfShorttermInvestments	136000000	USD
	us-gaap	Payments For Proceeds From Short Term Investments PaymentsForProceedsFromShortTermInvestments	80000000	USD
	ago	Proceedsfrom Paydownson Financial Guaranty Variable Interest Entities Assets ProceedsfromPaydownsonFinancialGuarantyVariableInterestEntitiesAssets	90000000	USD
	us-gaap	Proceeds From Equity Method Investment Dividends Or Distributions Return Of Capital ProceedsFromEquityMethodInvestmentDividendsOrDistributionsReturnOfCapital	0	USD
	us-gaap	Payments For Proceeds From Other Investing Activities PaymentsForProceedsFromOtherInvestingActivities	-19000000	USD
	us-gaap	Net Cash Provided By Used In Investing Activities NetCashProvidedByUsedInInvestingActivities	194000000	USD
	us-gaap	Payments Of Dividends Common Stock PaymentsOfDividendsCommonStock	55000000	USD
	us-gaap	Payments For Repurchase Of Common Stock PaymentsForRepurchaseOfCommonStock	380000000	USD
	ago	Paydown Of Financial Guaranty Variable Interest Entities Liabilities PaydownOfFinancialGuarantyVariableInterestEntitiesLiabilities	90000000	USD
	us-gaap	Repayments Of Long Term Debt RepaymentsOfLongTermDebt	73000000	USD
	us-gaap	Proceeds From Payments For Other Financing Activities ProceedsFromPaymentsForOtherFinancingActivities	-8000000	USD
	us-gaap	Net Cash Provided By Used In Financing Activities NetCashProvidedByUsedInFinancingActivities	-606000000	USD
	us-gaap	Effect Of Exchange Rate On Cash And Cash Equivalents EffectOfExchangeRateOnCashAndCashEquivalents	-2000000	USD
	ago	Increase Decreasein Cashand Restricted Cash IncreaseDecreaseinCashandRestrictedCash	-62000000	USD
CY2017Q4	ago	Cashand Restricted Cash CashandRestrictedCash	144000000	USD
CY2018Q3	ago	Cashand Restricted Cash CashandRestrictedCash	82000000	USD

Files In Submission

Name	View Source	Status
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0001273813-19-000050-index.html	Edgar Link	pending
0001273813-19-000050.txt	Edgar Link	pending
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$AGO
ASSURED GUARANTY LTD Stock $ago

2019 Q4 Form 10-Q Financial Statement

#000127381319000050 Filed on November 08, 2019

Income Statement

Balance Sheet

Cashflow Statement

Facts In Submission

Files In Submission

$AGO ASSURED GUARANTY LTD Stock $ago

2019 Q4 Form 10-Q Financial Statement

#000127381319000050 Filed on November 08, 2019

Income Statement

Balance Sheet

Cashflow Statement

Facts In Submission

Files In Submission

$AGO
ASSURED GUARANTY LTD Stock $ago