$AMG
AFFILIATED MANAGERS GROUP, INC. Stock $amg

$amg Overview Financials Valuation SEC Filings Company Website

2019 Q4 Form 10-K Financial Statement

#000100443420000011 Filed on February 28, 2020

Income Statement

Concept	2019 Q4	2018 Q4	2018 Q3
Revenue	$555.5M	$564.4M	$601.3M
YoY Change	-1.58%	-6.57%	2.66%
Cost Of Revenue
YoY Change
Gross Profit
YoY Change
Gross Profit Margin
Selling, General & Admin	$328.3M	$329.2M	$102.8M
YoY Change	-0.27%	-8.43%	11.86%
% of Gross Profit
Research & Development
YoY Change
% of Gross Profit
Depreciation & Amortization	$77.10M	$43.80M	$35.40M
YoY Change	76.03%	64.04%	36.15%
% of Gross Profit
Operating Expenses	$426.2M	$409.3M	$421.6M
YoY Change	4.13%	-0.7%	8.21%
Operating Profit
YoY Change
Interest Expense	-$35.10M	-$218.8M	$19.60M
YoY Change	-83.96%	-403.47%	-11.31%
% of Operating Profit
Other Income/Expense, Net
YoY Change
Pretax Income	$94.30M	-$63.60M	$250.4M
YoY Change	-248.27%	-124.09%	-11.49%
Income Tax	-$1.500M	$35.20M	$48.50M
% Of Pretax Income	-1.59%		19.37%
Net Earnings	$22.50M	-$151.3M	$124.9M
YoY Change	-114.87%	-147.97%	-0.4%
Net Earnings / Revenue	4.05%	-26.81%	20.77%
Basic Earnings Per Share			$2.35
Diluted Earnings Per Share	$0.46	-$2.88	$2.34
COMMON SHARES
Basic Shares Outstanding	49.27M shares	52.67M shares	53.10M shares
Diluted Shares Outstanding			55.40M shares

Balance Sheet

Concept	2019 Q4	2018 Q4	2018 Q3
SHORT-TERM ASSETS
Cash & Short-Term Investments	$599.0M	$684.8M	$592.2M
YoY Change	-12.53%	32.38%	26.78%
Cash & Equivalents	$539.6M	$565.5M	$448.1M
Short-Term Investments	$59.40M	$119.3M	$144.1M
Other Short-Term Assets
YoY Change
Inventory
Prepaid Expenses
Receivables	$417.1M	$400.6M	$524.5M
Other Receivables	$0.00	$0.00	$0.00
Total Short-Term Assets	$956.7M	$966.1M	$972.6M
YoY Change	-0.97%	10.63%	12.82%
LONG-TERM ASSETS
Property, Plant & Equipment	$92.30M	$104.3M	$104.8M
YoY Change	-11.51%	-6.04%	-6.18%
Goodwill	$2.652B	$2.633B	$2.648B
YoY Change	0.69%	-1.09%	-0.5%
Intangibles	$1.182B	$1.310B	$1.357B
YoY Change	-9.76%	-9.64%	-7.48%
Long-Term Investments	$352.6M	$513.2M	$524.5M
YoY Change	-31.29%	-4.79%	-85.2%
Other Assets
YoY Change
Total Long-Term Assets	$6.697B	$7.253B	$7.566B
YoY Change	-7.67%	-7.35%	-3.48%
TOTAL ASSETS
Total Short-Term Assets	$956.7M	$966.1M	$972.6M
Total Long-Term Assets	$6.697B	$7.253B	$7.566B
Total Assets	$7.654B	$8.219B	$8.539B
YoY Change	-6.88%	-5.55%	-1.87%
SHORT-TERM LIABILITIES
YoY Change
Accounts Payable		$746.6M	$761.6M
YoY Change			9.06%
Accrued Expenses	$634.6M
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	$634.6M	$746.6M	$761.6M
YoY Change	-15.0%	-7.51%	9.06%
LONG-TERM LIABILITIES
Long-Term Debt	$1.794B	$1.830B	$1.841B
YoY Change	-1.96%	-1.35%	-3.77%
Other Long-Term Liabilities	$359.1M	$162.7M	$166.5M
YoY Change	120.71%	-10.8%	-6.62%
Total Long-Term Liabilities	$2.153B	$1.992B	$2.008B
YoY Change	8.06%	-2.2%	-4.02%
TOTAL LIABILITIES
Total Short-Term Liabilities	$634.6M	$746.6M	$761.6M
Total Long-Term Liabilities	$2.153B	$1.992B	$2.008B
Total Liabilities	$3.238B	$3.251B	$3.249B
YoY Change	-0.39%	-1.85%	-6.98%
SHAREHOLDERS EQUITY
Retained Earnings	$3.820B	$3.877B	$4.044B
YoY Change	-1.47%	4.82%	19.14%
Common Stock	$707.8M	$836.2M	$708.5M
YoY Change	-15.36%	3.34%	-16.68%
Preferred Stock
YoY Change
Treasury Stock (at cost)	$1.481B	$1.147B	$1.074B
YoY Change	29.19%	72.76%	89.77%
Treasury Stock Shares	10.40M shares	6.500M shares
Shareholders Equity	$2.938B	$3.457B	$3.618B
YoY Change
Total Liabilities & Shareholders Equity	$7.654B	$8.219B	$8.539B
YoY Change	-6.88%	-5.55%	-1.87%

Cashflow Statement

Concept	2019 Q4	2018 Q4	2018 Q3
OPERATING ACTIVITIES
Net Income	$22.50M	-$151.3M	$124.9M
YoY Change	-114.87%	-147.97%	-0.4%
Depreciation, Depletion And Amortization	$77.10M	$43.80M	$35.40M
YoY Change	76.03%	64.04%	36.15%
Cash From Operating Activities	$310.5M	$261.2M	$298.9M
YoY Change	18.87%	-29.39%	-16.16%
INVESTING ACTIVITIES
Capital Expenditures	-$3.200M	-$5.200M	-$3.200M
YoY Change	-38.46%	13.04%	-52.24%
Acquisitions
YoY Change
Other Investing Activities	$118.7M	$7.900M	$7.800M
YoY Change	1402.53%	-41.48%	-26.42%
Cash From Investing Activities	$115.5M	$2.700M	$4.600M
YoY Change	4177.78%	-69.66%	17.95%
FINANCING ACTIVITIES
Cash Dividend Paid
YoY Change
Common Stock Issuance & Retirement, Net
YoY Change
Debt Paid & Issued, Net
YoY Change
Cash From Financing Activities	-300.5M	-141.4M	-245.9M
YoY Change	112.52%	-55.56%	-30.6%
NET CHANGE
Cash From Operating Activities	310.5M	261.2M	298.9M
Cash From Investing Activities	115.5M	2.700M	4.600M
Cash From Financing Activities	-300.5M	-141.4M	-245.9M
Net Change In Cash	125.5M	122.5M	57.60M
YoY Change	2.45%	102.15%	844.26%
FREE CASH FLOW
Cash From Operating Activities	$310.5M	$261.2M	$298.9M
Capital Expenditures	-$3.200M	-$5.200M	-$3.200M
Free Cash Flow	$313.7M	$266.4M	$302.1M
YoY Change	17.76%	-28.87%	-16.82%

Facts In Submission

Frame	Concept Type	Concept / XBRL Key	Value	Unit
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CY2019	dei	Entity Well Known Seasoned Issuer EntityWellKnownSeasonedIssuer	Yes
CY2019	dei	Current Fiscal Year End Date CurrentFiscalYearEndDate	--12-31
CY2019	dei	Document Fiscal Period Focus DocumentFiscalPeriodFocus	FY
CY2019	dei	Document Fiscal Year Focus DocumentFiscalYearFocus	2019
CY2019	dei	Entity Address Postal Zip Code EntityAddressPostalZipCode	33401
CY2019	dei	Entity Registrant Name EntityRegistrantName	AFFILIATED MANAGERS GROUP, INC.
CY2019	dei	Entity Central Index Key EntityCentralIndexKey	0001004434
CY2019	dei	Entity Incorporation State Country Code EntityIncorporationStateCountryCode	DE
CY2019	dei	Entity Tax Identification Number EntityTaxIdentificationNumber	04-3218510
CY2019	dei	Entity Address Address Line1 EntityAddressAddressLine1	777 South Flagler Drive
CY2019	dei	Entity Address City Or Town EntityAddressCityOrTown	West Palm Beach
CY2019	dei	Entity Address State Or Province EntityAddressStateOrProvince	FL
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CY2018Q4	us-gaap	Stockholders Equity Including Portion Attributable To Noncontrolling Interest StockholdersEquityIncludingPortionAttributableToNoncontrollingInterest	4134900000	USD
CY2019Q4	us-gaap	Stockholders Equity Including Portion Attributable To Noncontrolling Interest StockholdersEquityIncludingPortionAttributableToNoncontrollingInterest	3499100000	USD
CY2018Q4	us-gaap	Liabilities And Stockholders Equity LiabilitiesAndStockholdersEquity	8219100000	USD
CY2019Q4	us-gaap	Liabilities And Stockholders Equity LiabilitiesAndStockholdersEquity	7653500000	USD
CY2017	amg	Noncontrolling Interest Decreasefrom Redemptions NoncontrollingInterestDecreasefromRedemptions	241500000	USD
CY2017	amg	Noncontrolling Interest Decreasefrom Transfersto Noncontrolling Interest Holders NoncontrollingInterestDecreasefromTransferstoNoncontrollingInterestHolders	76800000	USD
CY2017	us-gaap	Minority Interest Decrease From Distributions To Noncontrolling Interest Holders MinorityInterestDecreaseFromDistributionsToNoncontrollingInterestHolders	352200000	USD
CY2017	amg	Noncontrolling Interest Increasefrom Contributionsfrom Affiliate NoncontrollingInterestIncreasefromContributionsfromAffiliate	6300000	USD
CY2016Q4	us-gaap	Stockholders Equity Including Portion Attributable To Noncontrolling Interest StockholdersEquityIncludingPortionAttributableToNoncontrollingInterest	4426500000	USD
CY2017	us-gaap	Profit Loss ProfitLoss	1008700000	USD
CY2017	us-gaap	Other Comprehensive Income Loss Net Of Tax OtherComprehensiveIncomeLossNetOfTax	119500000	USD
CY2017	us-gaap	Adjustments To Additional Paid In Capital Sharebased Compensation Requisite Service Period Recognition Value AdjustmentsToAdditionalPaidInCapitalSharebasedCompensationRequisiteServicePeriodRecognitionValue	40400000	USD
CY2017	us-gaap	Stock Issued During Period Value Share Based Compensation StockIssuedDuringPeriodValueShareBasedCompensation	21000000.0	USD
CY2017	us-gaap	Treasury Stock Value Acquired Cost Method TreasuryStockValueAcquiredCostMethod	416300000	USD
CY2017	us-gaap	Dividends Common Stock Cash DividendsCommonStockCash	45400000	USD
CY2017	amg	Adjustmentsto Additional Paidin Capital Stock Issued Issuance Costsand Other AdjustmentstoAdditionalPaidinCapitalStockIssuedIssuanceCostsandOther	600000	USD
CY2017	amg	Affiliate Equity Compensation Expense Including Adjustmentsand Portion Attributableto Noncontrolling Interest AffiliateEquityCompensationExpenseIncludingAdjustmentsandPortionAttributabletoNoncontrollingInterest	50000000.0	USD
CY2017	us-gaap	Noncontrolling Interest Increase From Subsidiary Equity Issuance NoncontrollingInterestIncreaseFromSubsidiaryEquityIssuance	3100000	USD
CY2017	amg	Noncontrolling Interest Increase Decreasefrom Purchaseof Interests NoncontrollingInterestIncreaseDecreasefromPurchaseofInterests	-34600000	USD
CY2017Q4	us-gaap	Stockholders Equity Including Portion Attributable To Noncontrolling Interest StockholdersEquityIncludingPortionAttributableToNoncontrollingInterest	4578500000	USD
CY2018	us-gaap	Profit Loss ProfitLoss	532300000	USD
CY2018	us-gaap	Other Comprehensive Income Loss Net Of Tax OtherComprehensiveIncomeLossNetOfTax	-102200000	USD
CY2018	us-gaap	Adjustments To Additional Paid In Capital Sharebased Compensation Requisite Service Period Recognition Value AdjustmentsToAdditionalPaidInCapitalSharebasedCompensationRequisiteServicePeriodRecognitionValue	44700000	USD
CY2018	us-gaap	Stock Issued During Period Value Share Based Compensation StockIssuedDuringPeriodValueShareBasedCompensation	-5000000.0	USD
CY2018	us-gaap	Treasury Stock Value Acquired Cost Method TreasuryStockValueAcquiredCostMethod	489500000	USD
CY2018	us-gaap	Dividends Common Stock Cash DividendsCommonStockCash	65300000	USD
CY2018	amg	Adjustmentsto Additional Paidin Capital Stock Issued Issuance Costsand Other AdjustmentstoAdditionalPaidinCapitalStockIssuedIssuanceCostsandOther	-500000	USD
CY2018	amg	Affiliate Equity Compensation Expense Including Adjustmentsand Portion Attributableto Noncontrolling Interest AffiliateEquityCompensationExpenseIncludingAdjustmentsandPortionAttributabletoNoncontrollingInterest	56400000	USD
CY2018	us-gaap	Noncontrolling Interest Increase From Subsidiary Equity Issuance NoncontrollingInterestIncreaseFromSubsidiaryEquityIssuance	7500000	USD
CY2018	amg	Noncontrolling Interest Increase Decreasefrom Purchaseof Interests NoncontrollingInterestIncreaseDecreasefromPurchaseofInterests	-6300000	USD
CY2018	amg	Noncontrolling Interest Decreasefrom Redemptions NoncontrollingInterestDecreasefromRedemptions	30800000	USD
CY2018	amg	Noncontrolling Interest Decreasefrom Transfersto Noncontrolling Interest Holders NoncontrollingInterestDecreasefromTransferstoNoncontrollingInterestHolders	44800000	USD
CY2018	amg	Noncontrolling Interest Increasefrom Contributionsfrom Affiliate NoncontrollingInterestIncreasefromContributionsfromAffiliate	17800000	USD
CY2018	us-gaap	Minority Interest Decrease From Distributions To Noncontrolling Interest Holders MinorityInterestDecreaseFromDistributionsToNoncontrollingInterestHolders	370500000	USD
CY2018Q4	us-gaap	Stockholders Equity Including Portion Attributable To Noncontrolling Interest StockholdersEquityIncludingPortionAttributableToNoncontrollingInterest	4134900000	USD
CY2019Q1	us-gaap	Cumulative Effect Of New Accounting Principle In Period Of Adoption CumulativeEffectOfNewAccountingPrincipleInPeriodOfAdoption	-6600000	USD
CY2019	us-gaap	Profit Loss ProfitLoss	305100000	USD
CY2019	us-gaap	Other Comprehensive Income Loss Net Of Tax OtherComprehensiveIncomeLossNetOfTax	12600000	USD
CY2019	us-gaap	Adjustments To Additional Paid In Capital Sharebased Compensation Requisite Service Period Recognition Value AdjustmentsToAdditionalPaidInCapitalSharebasedCompensationRequisiteServicePeriodRecognitionValue	49900000	USD
CY2019	us-gaap	Stock Issued During Period Value Share Based Compensation StockIssuedDuringPeriodValueShareBasedCompensation	-5400000	USD
CY2019	us-gaap	Treasury Stock Value Acquired Cost Method TreasuryStockValueAcquiredCostMethod	360800000	USD
CY2019	us-gaap	Dividends Common Stock Cash DividendsCommonStockCash	66100000	USD
CY2019	amg	Adjustmentsto Additional Paidin Capital Stock Issued Issuance Costsand Other AdjustmentstoAdditionalPaidinCapitalStockIssuedIssuanceCostsandOther	100000	USD
CY2019	amg	Affiliate Equity Compensation Expense Including Adjustmentsand Portion Attributableto Noncontrolling Interest AffiliateEquityCompensationExpenseIncludingAdjustmentsandPortionAttributabletoNoncontrollingInterest	40500000	USD
CY2019	us-gaap	Noncontrolling Interest Increase From Subsidiary Equity Issuance NoncontrollingInterestIncreaseFromSubsidiaryEquityIssuance	11200000	USD
CY2019	amg	Noncontrolling Interest Increase Decreasefrom Purchaseof Interests NoncontrollingInterestIncreaseDecreasefromPurchaseofInterests	-2900000	USD
CY2019	amg	Noncontrolling Interest Decreasefrom Redemptions NoncontrollingInterestDecreasefromRedemptions	166000000.0	USD
CY2019	amg	Noncontrolling Interest Decreasefrom Transfersto Noncontrolling Interest Holders NoncontrollingInterestDecreasefromTransferstoNoncontrollingInterestHolders	105000000.0	USD
CY2019	amg	Noncontrolling Interest Increasefrom Contributionsfrom Affiliate NoncontrollingInterestIncreasefromContributionsfromAffiliate	-300000	USD
CY2019	us-gaap	Minority Interest Decrease From Distributions To Noncontrolling Interest Holders MinorityInterestDecreaseFromDistributionsToNoncontrollingInterestHolders	347900000	USD
CY2019Q4	us-gaap	Stockholders Equity Including Portion Attributable To Noncontrolling Interest StockholdersEquityIncludingPortionAttributableToNoncontrollingInterest	3499100000	USD
CY2017	us-gaap	Profit Loss ProfitLoss	1008700000	USD
CY2018	us-gaap	Profit Loss ProfitLoss	532300000	USD
CY2019	us-gaap	Profit Loss ProfitLoss	305100000	USD
CY2017	amg	Amortizationand Impairmentsof Intangible Assets AmortizationandImpairmentsofIntangibleAssets	86400000	USD
CY2018	amg	Amortizationand Impairmentsof Intangible Assets AmortizationandImpairmentsofIntangibleAssets	114800000	USD
CY2019	amg	Amortizationand Impairmentsof Intangible Assets AmortizationandImpairmentsofIntangibleAssets	144500000	USD
CY2017	amg	Depreciation And Other Amortization DepreciationAndOtherAmortization	20300000	USD
CY2018	amg	Depreciation And Other Amortization DepreciationAndOtherAmortization	22000000.0	USD
CY2019	amg	Depreciation And Other Amortization DepreciationAndOtherAmortization	21300000	USD
CY2017	us-gaap	Deferred Income Tax Expense Benefit DeferredIncomeTaxExpenseBenefit	-123600000	USD
CY2018	us-gaap	Deferred Income Tax Expense Benefit DeferredIncomeTaxExpenseBenefit	51900000	USD
CY2019	us-gaap	Deferred Income Tax Expense Benefit DeferredIncomeTaxExpenseBenefit	-55800000	USD
CY2017	us-gaap	Income Loss From Equity Method Investments IncomeLossFromEquityMethodInvestments	302200000	USD
CY2018	us-gaap	Income Loss From Equity Method Investments IncomeLossFromEquityMethodInvestments	-200000	USD
CY2019	us-gaap	Income Loss From Equity Method Investments IncomeLossFromEquityMethodInvestments	-338000000.0	USD
CY2017	us-gaap	Equity Method Investment Dividends Or Distributions EquityMethodInvestmentDividendsOrDistributions	429800000	USD
CY2018	us-gaap	Equity Method Investment Dividends Or Distributions EquityMethodInvestmentDividendsOrDistributions	466300000	USD
CY2019	us-gaap	Equity Method Investment Dividends Or Distributions EquityMethodInvestmentDividendsOrDistributions	252400000	USD
CY2017	amg	Sharebased Compensationand Affiliate Equity Expense SharebasedCompensationandAffiliateEquityExpense	90400000	USD
CY2018	amg	Sharebased Compensationand Affiliate Equity Expense SharebasedCompensationandAffiliateEquityExpense	101100000	USD
CY2019	amg	Sharebased Compensationand Affiliate Equity Expense SharebasedCompensationandAffiliateEquityExpense	90400000	USD
CY2017	us-gaap	Other Noncash Income Expense OtherNoncashIncomeExpense	26300000	USD
CY2018	us-gaap	Other Noncash Income Expense OtherNoncashIncomeExpense	2700000	USD
CY2019	us-gaap	Other Noncash Income Expense OtherNoncashIncomeExpense	17700000	USD
CY2017	amg	Purchasesof Securitiesby Affiliate Sponsored Consolidated Products PurchasesofSecuritiesbyAffiliateSponsoredConsolidatedProducts	34100000	USD
CY2018	amg	Purchasesof Securitiesby Affiliate Sponsored Consolidated Products PurchasesofSecuritiesbyAffiliateSponsoredConsolidatedProducts	190800000	USD
CY2019	amg	Purchasesof Securitiesby Affiliate Sponsored Consolidated Products PurchasesofSecuritiesbyAffiliateSponsoredConsolidatedProducts	42300000	USD
CY2017	amg	Saleof Securitiesby Affiliate Sponsored Consolidated Products SaleofSecuritiesbyAffiliateSponsoredConsolidatedProducts	29900000	USD
CY2018	amg	Saleof Securitiesby Affiliate Sponsored Consolidated Products SaleofSecuritiesbyAffiliateSponsoredConsolidatedProducts	49600000	USD
CY2019	amg	Saleof Securitiesby Affiliate Sponsored Consolidated Products SaleofSecuritiesbyAffiliateSponsoredConsolidatedProducts	16500000	USD
CY2017	us-gaap	Increase Decrease In Receivables IncreaseDecreaseInReceivables	53500000	USD
CY2018	us-gaap	Increase Decrease In Receivables IncreaseDecreaseInReceivables	-14400000	USD
CY2019	us-gaap	Increase Decrease In Receivables IncreaseDecreaseInReceivables	15800000	USD
CY2017	us-gaap	Increase Decrease In Other Operating Assets IncreaseDecreaseInOtherOperatingAssets	7700000	USD
CY2018	us-gaap	Increase Decrease In Other Operating Assets IncreaseDecreaseInOtherOperatingAssets	11700000	USD
CY2019	us-gaap	Increase Decrease In Other Operating Assets IncreaseDecreaseInOtherOperatingAssets	51400000	USD
CY2017	us-gaap	Increase Decrease In Operating Liabilities IncreaseDecreaseInOperatingLiabilities	52300000	USD
CY2018	us-gaap	Increase Decrease In Operating Liabilities IncreaseDecreaseInOperatingLiabilities	-6800000	USD
CY2019	us-gaap	Payments To Acquire Property Plant And Equipment PaymentsToAcquirePropertyPlantAndEquipment	9600000	USD
CY2019	us-gaap	Increase Decrease In Operating Liabilities IncreaseDecreaseInOperatingLiabilities	-56100000	USD
CY2017	us-gaap	Net Cash Provided By Used In Operating Activities NetCashProvidedByUsedInOperatingActivities	1170400000	USD
CY2018	us-gaap	Net Cash Provided By Used In Operating Activities NetCashProvidedByUsedInOperatingActivities	1140600000	USD
CY2019	us-gaap	Net Cash Provided By Used In Operating Activities NetCashProvidedByUsedInOperatingActivities	929100000	USD
CY2017	us-gaap	Payments To Acquire Interest In Subsidiaries And Affiliates PaymentsToAcquireInterestInSubsidiariesAndAffiliates	30600000	USD
CY2018	us-gaap	Payments To Acquire Interest In Subsidiaries And Affiliates PaymentsToAcquireInterestInSubsidiariesAndAffiliates	7300000	USD
CY2019	us-gaap	Payments To Acquire Interest In Subsidiaries And Affiliates PaymentsToAcquireInterestInSubsidiariesAndAffiliates	162300000	USD
CY2017	us-gaap	Proceeds From Divestiture Of Interest In Subsidiaries And Affiliates ProceedsFromDivestitureOfInterestInSubsidiariesAndAffiliates	0	USD
CY2018	us-gaap	Proceeds From Divestiture Of Interest In Subsidiaries And Affiliates ProceedsFromDivestitureOfInterestInSubsidiariesAndAffiliates	0	USD
CY2019	us-gaap	Proceeds From Divestiture Of Interest In Subsidiaries And Affiliates ProceedsFromDivestitureOfInterestInSubsidiariesAndAffiliates	117700000	USD
CY2017	us-gaap	Payments To Acquire Property Plant And Equipment PaymentsToAcquirePropertyPlantAndEquipment	18500000	USD
CY2018	us-gaap	Payments To Acquire Property Plant And Equipment PaymentsToAcquirePropertyPlantAndEquipment	18700000	USD
CY2017	us-gaap	Payments To Acquire Marketable Securities PaymentsToAcquireMarketableSecurities	37200000	USD
CY2018	us-gaap	Payments To Acquire Marketable Securities PaymentsToAcquireMarketableSecurities	40800000	USD
CY2019	us-gaap	Payments To Acquire Marketable Securities PaymentsToAcquireMarketableSecurities	43100000	USD
CY2017	us-gaap	Payments For Proceeds From Investments PaymentsForProceedsFromInvestments	-100100000	USD
CY2018	us-gaap	Payments For Proceeds From Investments PaymentsForProceedsFromInvestments	-48600000	USD
CY2019	us-gaap	Payments For Proceeds From Investments PaymentsForProceedsFromInvestments	-72900000	USD
CY2017	us-gaap	Net Cash Provided By Used In Investing Activities NetCashProvidedByUsedInInvestingActivities	13800000	USD
CY2018	us-gaap	Net Cash Provided By Used In Investing Activities NetCashProvidedByUsedInInvestingActivities	-18200000	USD
CY2019	us-gaap	Net Cash Provided By Used In Investing Activities NetCashProvidedByUsedInInvestingActivities	-24400000	USD
CY2017	us-gaap	Proceeds From Issuance Of Long Term Debt ProceedsFromIssuanceOfLongTermDebt	545000000.0	USD
CY2018	us-gaap	Proceeds From Issuance Of Long Term Debt ProceedsFromIssuanceOfLongTermDebt	1150000000.0	USD
CY2019	us-gaap	Proceeds From Issuance Of Long Term Debt ProceedsFromIssuanceOfLongTermDebt	470700000	USD
CY2017	us-gaap	Repayments Of Long Term Debt RepaymentsOfLongTermDebt	805000000.0	USD
CY2018	us-gaap	Repayments Of Long Term Debt RepaymentsOfLongTermDebt	1180600000	USD
CY2019	us-gaap	Repayments Of Long Term Debt RepaymentsOfLongTermDebt	510000000.0	USD
CY2017	us-gaap	Payments For Repurchase Of Common Stock PaymentsForRepurchaseOfCommonStock	351300000	USD
CY2018	us-gaap	Payments For Repurchase Of Common Stock PaymentsForRepurchaseOfCommonStock	496100000	USD
CY2019	us-gaap	Payments For Repurchase Of Common Stock PaymentsForRepurchaseOfCommonStock	356100000	USD
CY2017	us-gaap	Payments Of Dividends Common Stock PaymentsOfDividendsCommonStock	44900000	USD
CY2018	us-gaap	Payments Of Dividends Common Stock PaymentsOfDividendsCommonStock	64400000	USD
CY2019	us-gaap	Payments Of Dividends Common Stock PaymentsOfDividendsCommonStock	65300000	USD
CY2017	us-gaap	Payments Of Dividends Minority Interest PaymentsOfDividendsMinorityInterest	352200000	USD
CY2018	us-gaap	Payments Of Dividends Minority Interest PaymentsOfDividendsMinorityInterest	370500000	USD
CY2019	us-gaap	Payments Of Dividends Minority Interest PaymentsOfDividendsMinorityInterest	347900000	USD
CY2017	amg	Proceeds From Payments For Affiliate Equity Issuances And Repurchases ProceedsFromPaymentsForAffiliateEquityIssuancesAndRepurchases	-165700000	USD
CY2018	amg	Proceeds From Payments For Affiliate Equity Issuances And Repurchases ProceedsFromPaymentsForAffiliateEquityIssuancesAndRepurchases	-113700000	USD
CY2019	amg	Proceeds From Payments For Affiliate Equity Issuances And Repurchases ProceedsFromPaymentsForAffiliateEquityIssuancesAndRepurchases	-135500000	USD
CY2017	amg	Subscriptionsto Affiliate Sponsored Consolidated Products Netof Redemptions SubscriptionstoAffiliateSponsoredConsolidatedProductsNetofRedemptions	2700000	USD
CY2018	amg	Subscriptionsto Affiliate Sponsored Consolidated Products Netof Redemptions SubscriptionstoAffiliateSponsoredConsolidatedProductsNetofRedemptions	132800000	USD
CY2019	amg	Subscriptionsto Affiliate Sponsored Consolidated Products Netof Redemptions SubscriptionstoAffiliateSponsoredConsolidatedProductsNetofRedemptions	19000000.0	USD
CY2019	us-gaap	Cash Cash Equivalents Restricted Cash And Restricted Cash Equivalents Period Increase Decrease Including Exchange Rate Effect CashCashEquivalentsRestrictedCashAndRestrictedCashEquivalentsPeriodIncreaseDecreaseIncludingExchangeRateEffect	-21300000	USD
CY2016Q4	us-gaap	Cash Cash Equivalents Restricted Cash And Restricted Cash Equivalents CashCashEquivalentsRestrictedCashAndRestrictedCashEquivalents	430800000	USD
CY2017	us-gaap	Proceeds From Payments For Other Financing Activities ProceedsFromPaymentsForOtherFinancingActivities	-18300000	USD
CY2018	us-gaap	Proceeds From Payments For Other Financing Activities ProceedsFromPaymentsForOtherFinancingActivities	-40600000	USD
CY2019	us-gaap	Proceeds From Payments For Other Financing Activities ProceedsFromPaymentsForOtherFinancingActivities	-9600000	USD
CY2017	us-gaap	Net Cash Provided By Used In Financing Activities NetCashProvidedByUsedInFinancingActivities	-1189700000	USD
CY2018	us-gaap	Net Cash Provided By Used In Financing Activities NetCashProvidedByUsedInFinancingActivities	-983100000	USD
CY2019	us-gaap	Net Cash Provided By Used In Financing Activities NetCashProvidedByUsedInFinancingActivities	-934700000	USD
CY2017	us-gaap	Effect Of Exchange Rate On Cash Cash Equivalents Restricted Cash And Restricted Cash Equivalents EffectOfExchangeRateOnCashCashEquivalentsRestrictedCashAndRestrictedCashEquivalents	14200000	USD
CY2018	us-gaap	Effect Of Exchange Rate On Cash Cash Equivalents Restricted Cash And Restricted Cash Equivalents EffectOfExchangeRateOnCashCashEquivalentsRestrictedCashAndRestrictedCashEquivalents	-10100000	USD
CY2019	us-gaap	Effect Of Exchange Rate On Cash Cash Equivalents Restricted Cash And Restricted Cash Equivalents EffectOfExchangeRateOnCashCashEquivalentsRestrictedCashAndRestrictedCashEquivalents	8700000	USD
CY2017	us-gaap	Cash Cash Equivalents Restricted Cash And Restricted Cash Equivalents Period Increase Decrease Including Exchange Rate Effect CashCashEquivalentsRestrictedCashAndRestrictedCashEquivalentsPeriodIncreaseDecreaseIncludingExchangeRateEffect	8700000	USD
CY2018	us-gaap	Cash Cash Equivalents Restricted Cash And Restricted Cash Equivalents Period Increase Decrease Including Exchange Rate Effect CashCashEquivalentsRestrictedCashAndRestrictedCashEquivalentsPeriodIncreaseDecreaseIncludingExchangeRateEffect	129200000	USD
CY2017Q4	us-gaap	Cash Cash Equivalents Restricted Cash And Restricted Cash Equivalents CashCashEquivalentsRestrictedCashAndRestrictedCashEquivalents	439500000	USD
CY2018Q4	us-gaap	Cash Cash Equivalents Restricted Cash And Restricted Cash Equivalents CashCashEquivalentsRestrictedCashAndRestrictedCashEquivalents	565500000	USD
CY2017	us-gaap	Cash Divested From Deconsolidation CashDivestedFromDeconsolidation	0	USD
CY2018	us-gaap	Cash Divested From Deconsolidation CashDivestedFromDeconsolidation	3200000	USD
CY2019	us-gaap	Cash Divested From Deconsolidation CashDivestedFromDeconsolidation	4600000	USD
CY2017Q4	us-gaap	Cash Cash Equivalents Restricted Cash And Restricted Cash Equivalents CashCashEquivalentsRestrictedCashAndRestrictedCashEquivalents	439500000	USD
CY2018Q4	us-gaap	Cash Cash Equivalents Restricted Cash And Restricted Cash Equivalents CashCashEquivalentsRestrictedCashAndRestrictedCashEquivalents	565500000	USD
CY2019Q4	us-gaap	Cash Cash Equivalents Restricted Cash And Restricted Cash Equivalents CashCashEquivalentsRestrictedCashAndRestrictedCashEquivalents	539600000	USD
CY2017	us-gaap	Interest Paid Net InterestPaidNet	82100000	USD
CY2018	us-gaap	Interest Paid Net InterestPaidNet	76900000	USD
CY2019	us-gaap	Interest Paid Net InterestPaidNet	84100000	USD
CY2017	us-gaap	Income Taxes Paid Net IncomeTaxesPaidNet	165000000.0	USD
CY2018	us-gaap	Income Taxes Paid Net IncomeTaxesPaidNet	160200000	USD
CY2019	us-gaap	Income Taxes Paid Net IncomeTaxesPaidNet	102700000	USD
CY2019	us-gaap	Operating Lease Payments OperatingLeasePayments	35400000	USD
CY2017	amg	Payables Recorded For Affiliate Equity Purchases PayablesRecordedForAffiliateEquityPurchases	47300000	USD
CY2018	amg	Payables Recorded For Affiliate Equity Purchases PayablesRecordedForAffiliateEquityPurchases	36200000	USD
CY2019	amg	Payables Recorded For Affiliate Equity Purchases PayablesRecordedForAffiliateEquityPurchases	19800000	USD
CY2017	amg	Payables Recorded But Not Yet Paid Share Repurchases PayablesRecordedButNotYetPaidShareRepurchases	23100000	USD
CY2018	amg	Payables Recorded But Not Yet Paid Share Repurchases PayablesRecordedButNotYetPaidShareRepurchases	6900000	USD
CY2019	amg	Payables Recorded But Not Yet Paid Share Repurchases PayablesRecordedButNotYetPaidShareRepurchases	10600000	USD
CY2017	amg	Stock Issued Under Other Incentive Plans StockIssuedUnderOtherIncentivePlans	59300000	USD
CY2018	amg	Stock Issued Under Other Incentive Plans StockIssuedUnderOtherIncentivePlans	4700000	USD
CY2019	amg	Stock Issued Under Other Incentive Plans StockIssuedUnderOtherIncentivePlans	32700000	USD
CY2017	amg	Shares Receivedfor Tax Withholdingfor Share Based Compensation Value SharesReceivedforTaxWithholdingforShareBasedCompensationValue	20000000.0	USD
CY2018	amg	Shares Receivedfor Tax Withholdingfor Share Based Compensation Value SharesReceivedforTaxWithholdingforShareBasedCompensationValue	14700000	USD
CY2019	amg	Shares Receivedfor Tax Withholdingfor Share Based Compensation Value SharesReceivedforTaxWithholdingforShareBasedCompensationValue	6400000	USD
CY2017	amg	Shares Received From Stock Options Exercised Value SharesReceivedFromStockOptionsExercisedValue	30200000	USD
CY2018	amg	Shares Received From Stock Options Exercised Value SharesReceivedFromStockOptionsExercisedValue	4100000	USD
CY2019	amg	Shares Received From Stock Options Exercised Value SharesReceivedFromStockOptionsExercisedValue	0	USD
CY2019	us-gaap	Right Of Use Asset Obtained In Exchange For Operating Lease Liability RightOfUseAssetObtainedInExchangeForOperatingLeaseLiability	189700000	USD
CY2019	us-gaap	Number Of Operating Segments NumberOfOperatingSegments	1	segment
CY2019	us-gaap	Prior Period Reclassification Adjustment Description PriorPeriodReclassificationAdjustmentDescription	Reclassifications have been made to the prior period’s financial statements to conform to the current period’s presentation.
CY2019	us-gaap	Use Of Estimates UseOfEstimates	<div style="line-height:120%;padding-bottom:10px;padding-top:10px;text-indent:24px;font-size:10pt;"><span style="font-family:inherit;font-size:10pt;">The preparation of financial statements in conformity with GAAP requires management to make estimates and assumptions that affect the reported amounts and disclosures in the financial statements. Actual results could differ from those estimates.</span></div>
CY2018Q4	amg	Marketable Securities Unrealized Gains MarketableSecuritiesUnrealizedGains	1100000	USD
CY2019Q4	amg	Marketable Securities Unrealized Gains MarketableSecuritiesUnrealizedGains	2100000	USD
CY2018Q4	amg	Marketable Securities Cost MarketableSecuritiesCost	126800000	USD
CY2018Q4	amg	Marketable Securities Unrealized Losses MarketableSecuritiesUnrealizedLosses	8600000	USD
CY2019	us-gaap	Concentration Risk Credit Risk ConcentrationRiskCreditRisk	<div style="line-height:120%;font-size:10pt;"><span style="font-family:inherit;font-size:10pt;font-style:italic;">Concentration of Credit Risk</span></div><div style="line-height:120%;padding-left:24px;font-size:10pt;"><span style="font-family:inherit;font-size:10pt;"><br/></span></div><div style="line-height:120%;text-indent:24px;font-size:10pt;"><span style="font-family:inherit;font-size:10pt;">Financial instruments that potentially subject the Company to significant concentrations of credit risk consist principally of cash investments and derivative financial instruments. The Company and its Affiliates maintain cash and cash equivalents, investments and, at times, certain derivative financial instruments with various high credit-quality financial institutions. These financial institutions are typically located in countries in which the Company and its Affiliates operate. For the Company and certain of its Affiliates, cash deposits at a financial institution may exceed Federal Deposit Insurance Corporation insurance limits.</span></div>
CY2019Q4	amg	Marketable Securities Cost MarketableSecuritiesCost	57900000	USD
CY2019Q4	amg	Marketable Securities Unrealized Losses MarketableSecuritiesUnrealizedLosses	600000	USD
CY2018Q4	us-gaap	Marketable Securities MarketableSecurities	119300000	USD
CY2019Q4	us-gaap	Marketable Securities MarketableSecurities	59400000	USD
CY2018	us-gaap	Proceeds From Sale And Maturity Of Marketable Securities ProceedsFromSaleAndMaturityOfMarketableSecurities	81400000	USD
CY2019	us-gaap	Proceeds From Sale And Maturity Of Marketable Securities ProceedsFromSaleAndMaturityOfMarketableSecurities	38000000.0	USD
CY2018	us-gaap	Marketable Securities Realized Gain Loss MarketableSecuritiesRealizedGainLoss	6900000	USD
CY2019	us-gaap	Marketable Securities Realized Gain Loss MarketableSecuritiesRealizedGainLoss	1100000	USD
CY2018Q4	us-gaap	Investments In Affiliates Subsidiaries Associates And Joint Ventures InvestmentsInAffiliatesSubsidiariesAssociatesAndJointVentures	2791000000.0	USD
CY2019Q4	us-gaap	Investments In Affiliates Subsidiaries Associates And Joint Ventures InvestmentsInAffiliatesSubsidiariesAssociatesAndJointVentures	2195600000	USD
CY2018Q4	us-gaap	Equity Method Investments EquityMethodInvestments	513200000	USD
CY2019Q4	us-gaap	Equity Method Investments EquityMethodInvestments	352600000	USD
CY2018Q4	us-gaap	Long Term Debt LongTermDebt	1829600000	USD
CY2019Q4	us-gaap	Long Term Debt LongTermDebt	1793800000	USD
CY2019Q4	us-gaap	Long Term Debt Maturities Repayments Of Principal In Year Three LongTermDebtMaturitiesRepaymentsOfPrincipalInYearThree	450000000.0	USD
CY2019Q4	us-gaap	Long Term Debt Maturities Repayments Of Principal In Year Four LongTermDebtMaturitiesRepaymentsOfPrincipalInYearFour	400000000.0	USD
CY2019Q4	amg	Derivative Net Liability Position Numberof Instruments DerivativeNetLiabilityPositionNumberofInstruments	0	derivative
CY2019Q4	amg	Investment Commitment Amount InvestmentCommitmentAmount	127200000	USD
CY2019	amg	Fair Value Investments Entities That Calculate Na Vs Lifeof Fund FairValueInvestmentsEntitiesThatCalculateNAVsLifeofFund	P15Y
CY2017Q4	us-gaap	Goodwill Goodwill	2662500000	USD
CY2018Q4	us-gaap	Goodwill Goodwill	2633400000	USD
CY2018	us-gaap	Goodwill Foreign Currency Translation Gain Loss GoodwillForeignCurrencyTranslationGainLoss	-29100000	USD
CY2019	us-gaap	Goodwill Foreign Currency Translation Gain Loss GoodwillForeignCurrencyTranslationGainLoss	18300000	USD
CY2018Q4	us-gaap	Goodwill Goodwill	2633400000	USD
CY2019Q4	us-gaap	Goodwill Goodwill	2651700000	USD
	us-gaap	Goodwill Impairment Loss GoodwillImpairmentLoss	0	USD
CY2019	us-gaap	Equity Method Investment Other Than Temporary Impairment EquityMethodInvestmentOtherThanTemporaryImpairment	0	USD
CY2017	us-gaap	Equity Method Investment Summarized Financial Information Revenue EquityMethodInvestmentSummarizedFinancialInformationRevenue	3126300000	USD
CY2018	us-gaap	Equity Method Investment Summarized Financial Information Revenue EquityMethodInvestmentSummarizedFinancialInformationRevenue	3231700000	USD
CY2019	us-gaap	Equity Method Investment Summarized Financial Information Revenue EquityMethodInvestmentSummarizedFinancialInformationRevenue	2760900000	USD
CY2017	us-gaap	Equity Method Investment Summarized Financial Information Net Income Loss EquityMethodInvestmentSummarizedFinancialInformationNetIncomeLoss	2182700000	USD
CY2018	us-gaap	Equity Method Investment Summarized Financial Information Net Income Loss EquityMethodInvestmentSummarizedFinancialInformationNetIncomeLoss	1286100000	USD
CY2019	us-gaap	Equity Method Investment Summarized Financial Information Net Income Loss EquityMethodInvestmentSummarizedFinancialInformationNetIncomeLoss	1061300000	USD
CY2018Q4	us-gaap	Equity Method Investment Summarized Financial Information Assets EquityMethodInvestmentSummarizedFinancialInformationAssets	2730400000	USD
CY2019Q4	us-gaap	Equity Method Investment Summarized Financial Information Assets EquityMethodInvestmentSummarizedFinancialInformationAssets	2718500000	USD
CY2018Q4	amg	Equity Method Investment Summarized Financial Information Liabilitiesand Noncontrolling Interests EquityMethodInvestmentSummarizedFinancialInformationLiabilitiesandNoncontrollingInterests	1235100000	USD
CY2019Q4	amg	Equity Method Investment Summarized Financial Information Liabilitiesand Noncontrolling Interests EquityMethodInvestmentSummarizedFinancialInformationLiabilitiesandNoncontrollingInterests	1212700000	USD
CY2019Q4	us-gaap	Retained Earnings Undistributed Earnings From Equity Method Investees RetainedEarningsUndistributedEarningsFromEquityMethodInvestees	115000000.0	USD
CY2019	us-gaap	Operating Lease Cost OperatingLeaseCost	41700000	USD
CY2019	us-gaap	Short Term Lease Cost ShortTermLeaseCost	2100000	USD
CY2019	us-gaap	Variable Lease Cost VariableLeaseCost	100000	USD
CY2019	us-gaap	Sublease Income SubleaseIncome	4400000	USD
CY2019	us-gaap	Lease Cost LeaseCost	39500000	USD
CY2019	amg	Rightof Use Asset Obtainedin Exchangefor Operating Lease Liability After Adoption RightofUseAssetObtainedinExchangeforOperatingLeaseLiabilityAfterAdoption	26100000	USD
CY2019Q4	us-gaap	Operating Lease Weighted Average Remaining Lease Term1 OperatingLeaseWeightedAverageRemainingLeaseTerm1	P8Y
CY2019Q4	us-gaap	Operating Lease Weighted Average Discount Rate Percent OperatingLeaseWeightedAverageDiscountRatePercent	0.04
CY2019Q4	us-gaap	Lessee Operating Lease Liability Payments Due Next Twelve Months LesseeOperatingLeaseLiabilityPaymentsDueNextTwelveMonths	38900000	USD
CY2019Q4	us-gaap	Lessee Operating Lease Liability Payments Due Year Two LesseeOperatingLeaseLiabilityPaymentsDueYearTwo	38300000	USD
CY2019Q4	us-gaap	Lessee Operating Lease Liability Payments Due Year Three LesseeOperatingLeaseLiabilityPaymentsDueYearThree	31400000	USD
CY2019Q4	us-gaap	Lessee Operating Lease Liability Payments Due Year Four LesseeOperatingLeaseLiabilityPaymentsDueYearFour	26700000	USD
CY2019Q4	us-gaap	Lessee Operating Lease Liability Payments Due Year Five LesseeOperatingLeaseLiabilityPaymentsDueYearFive	21100000	USD
CY2019Q4	us-gaap	Lessee Operating Lease Liability Payments Due After Year Five LesseeOperatingLeaseLiabilityPaymentsDueAfterYearFive	82400000	USD
CY2019Q4	us-gaap	Lessee Operating Lease Liability Payments Due LesseeOperatingLeaseLiabilityPaymentsDue	238800000	USD
CY2019Q4	us-gaap	Lessee Operating Lease Liability Undiscounted Excess Amount LesseeOperatingLeaseLiabilityUndiscountedExcessAmount	50400000	USD
CY2018Q4	us-gaap	Operating Leases Future Minimum Payments Due Current OperatingLeasesFutureMinimumPaymentsDueCurrent	35500000	USD
CY2018Q4	us-gaap	Operating Leases Future Minimum Payments Due In Two Years OperatingLeasesFutureMinimumPaymentsDueInTwoYears	36900000	USD
CY2018Q4	us-gaap	Operating Leases Future Minimum Payments Due In Three Years OperatingLeasesFutureMinimumPaymentsDueInThreeYears	34800000	USD
CY2018Q4	us-gaap	Operating Leases Future Minimum Payments Due In Four Years OperatingLeasesFutureMinimumPaymentsDueInFourYears	27700000	USD
CY2018Q4	us-gaap	Operating Leases Future Minimum Payments Due In Five Years OperatingLeasesFutureMinimumPaymentsDueInFiveYears	23400000	USD
CY2018Q4	us-gaap	Operating Leases Future Minimum Payments Due Thereafter OperatingLeasesFutureMinimumPaymentsDueThereafter	75200000	USD
CY2017	us-gaap	Operating Leases Rent Expense Net OperatingLeasesRentExpenseNet	37500000	USD
CY2018	us-gaap	Operating Leases Rent Expense Net OperatingLeasesRentExpenseNet	40500000	USD
CY2019	us-gaap	Operating Lease Expense OperatingLeaseExpense	45300000	USD
CY2019Q4	us-gaap	Operating Lease Impairment Loss OperatingLeaseImpairmentLoss	8100000	USD
CY2018Q4	us-gaap	Property Plant And Equipment Gross PropertyPlantAndEquipmentGross	250700000	USD
CY2019Q4	us-gaap	Property Plant And Equipment Gross PropertyPlantAndEquipmentGross	251100000	USD
CY2018Q4	us-gaap	Accumulated Depreciation Depletion And Amortization Property Plant And Equipment AccumulatedDepreciationDepletionAndAmortizationPropertyPlantAndEquipment	146400000	USD
CY2019Q4	us-gaap	Accumulated Depreciation Depletion And Amortization Property Plant And Equipment AccumulatedDepreciationDepletionAndAmortizationPropertyPlantAndEquipment	158800000	USD
CY2018Q4	us-gaap	Property Plant And Equipment Net PropertyPlantAndEquipmentNet	104300000	USD
CY2019Q4	us-gaap	Property Plant And Equipment Net PropertyPlantAndEquipmentNet	92300000	USD
CY2018Q4	us-gaap	Employee Related Liabilities Current And Noncurrent EmployeeRelatedLiabilitiesCurrentAndNoncurrent	463200000	USD
CY2019Q4	us-gaap	Employee Related Liabilities Current And Noncurrent EmployeeRelatedLiabilitiesCurrentAndNoncurrent	421500000	USD
CY2018Q4	us-gaap	Other Accrued Liabilities Current And Noncurrent OtherAccruedLiabilitiesCurrentAndNoncurrent	283400000	USD
CY2019Q4	us-gaap	Other Accrued Liabilities Current And Noncurrent OtherAccruedLiabilitiesCurrentAndNoncurrent	213100000	USD
CY2018Q4	us-gaap	Accounts Payable And Accrued Liabilities Current And Noncurrent AccountsPayableAndAccruedLiabilitiesCurrentAndNoncurrent	746600000	USD
CY2019Q4	us-gaap	Accounts Payable And Accrued Liabilities Current And Noncurrent AccountsPayableAndAccruedLiabilitiesCurrentAndNoncurrent	634600000	USD
CY2017	us-gaap	Share Based Compensation Arrangement By Share Based Payment Award Equity Instruments Other Than Options Vested In Period Total Fair Value ShareBasedCompensationArrangementByShareBasedPaymentAwardEquityInstrumentsOtherThanOptionsVestedInPeriodTotalFairValue	59400000	USD
CY2018	us-gaap	Share Based Compensation Arrangement By Share Based Payment Award Equity Instruments Other Than Options Vested In Period Total Fair Value ShareBasedCompensationArrangementByShareBasedPaymentAwardEquityInstrumentsOtherThanOptionsVestedInPeriodTotalFairValue	5900000	USD
CY2019	us-gaap	Share Based Compensation Arrangement By Share Based Payment Award Equity Instruments Other Than Options Vested In Period Total Fair Value ShareBasedCompensationArrangementByShareBasedPaymentAwardEquityInstrumentsOtherThanOptionsVestedInPeriodTotalFairValue	18900000	USD
CY2017	us-gaap	Allocated Share Based Compensation Expense AllocatedShareBasedCompensationExpense	40400000	USD
CY2017	us-gaap	Employee Service Share Based Compensation Tax Benefit From Compensation Expense EmployeeServiceShareBasedCompensationTaxBenefitFromCompensationExpense	13600000	USD
CY2018	us-gaap	Allocated Share Based Compensation Expense AllocatedShareBasedCompensationExpense	44700000	USD
CY2018	us-gaap	Employee Service Share Based Compensation Tax Benefit From Compensation Expense EmployeeServiceShareBasedCompensationTaxBenefitFromCompensationExpense	11200000	USD
CY2019	us-gaap	Allocated Share Based Compensation Expense AllocatedShareBasedCompensationExpense	49900000	USD
CY2019	us-gaap	Employee Service Share Based Compensation Tax Benefit From Compensation Expense EmployeeServiceShareBasedCompensationTaxBenefitFromCompensationExpense	8200000	USD
CY2017	us-gaap	Excess Tax Benefit From Share Based Compensation Operating Activities ExcessTaxBenefitFromShareBasedCompensationOperatingActivities	10900000	USD
CY2018	us-gaap	Excess Tax Benefit From Share Based Compensation Operating Activities ExcessTaxBenefitFromShareBasedCompensationOperatingActivities	700000	USD
CY2019	us-gaap	Excess Tax Benefit From Share Based Compensation Operating Activities ExcessTaxBenefitFromShareBasedCompensationOperatingActivities	-3200000	USD
CY2018Q4	us-gaap	Employee Service Share Based Compensation Nonvested Awards Total Compensation Cost Not Yet Recognized EmployeeServiceShareBasedCompensationNonvestedAwardsTotalCompensationCostNotYetRecognized	54100000	USD
CY2019Q4	us-gaap	Employee Service Share Based Compensation Nonvested Awards Total Compensation Cost Not Yet Recognized EmployeeServiceShareBasedCompensationNonvestedAwardsTotalCompensationCostNotYetRecognized	106600000	USD
CY2019	us-gaap	Employee Service Share Based Compensation Nonvested Awards Total Compensation Cost Not Yet Recognized Period For Recognition1 EmployeeServiceShareBasedCompensationNonvestedAwardsTotalCompensationCostNotYetRecognizedPeriodForRecognition1	P3Y
CY2018Q4	us-gaap	Share Based Compensation Arrangement By Share Based Payment Award Options Outstanding Number ShareBasedCompensationArrangementByShareBasedPaymentAwardOptionsOutstandingNumber	500000	shares
CY2018Q4	us-gaap	Share Based Compensation Arrangement By Share Based Payment Award Options Outstanding Weighted Average Exercise Price ShareBasedCompensationArrangementByShareBasedPaymentAwardOptionsOutstandingWeightedAverageExercisePrice	130.81
CY2019	us-gaap	Share Based Compensation Arrangement By Share Based Payment Award Options Grants In Period ShareBasedCompensationArrangementByShareBasedPaymentAwardOptionsGrantsInPeriod	1900000	shares
CY2019	us-gaap	Share Based Compensation Arrangements By Share Based Payment Award Options Grants In Period Weighted Average Exercise Price ShareBasedCompensationArrangementsByShareBasedPaymentAwardOptionsGrantsInPeriodWeightedAverageExercisePrice	74.90
CY2019	us-gaap	Stock Issued During Period Shares Stock Options Exercised StockIssuedDuringPeriodSharesStockOptionsExercised	0.0	shares
CY2019	us-gaap	Share Based Compensation Arrangements By Share Based Payment Award Options Exercises In Period Weighted Average Exercise Price ShareBasedCompensationArrangementsByShareBasedPaymentAwardOptionsExercisesInPeriodWeightedAverageExercisePrice	71.49
CY2019	us-gaap	Share Based Compensation Arrangement By Share Based Payment Award Options Forfeitures In Period ShareBasedCompensationArrangementByShareBasedPaymentAwardOptionsForfeituresInPeriod	100000	shares
CY2019	us-gaap	Share Based Compensation Arrangements By Share Based Payment Award Options Forfeitures In Period Weighted Average Exercise Price ShareBasedCompensationArrangementsByShareBasedPaymentAwardOptionsForfeituresInPeriodWeightedAverageExercisePrice	121.94
CY2019Q4	us-gaap	Share Based Compensation Arrangement By Share Based Payment Award Options Outstanding Number ShareBasedCompensationArrangementByShareBasedPaymentAwardOptionsOutstandingNumber	2300000	shares
CY2019Q4	us-gaap	Share Based Compensation Arrangement By Share Based Payment Award Options Outstanding Weighted Average Exercise Price ShareBasedCompensationArrangementByShareBasedPaymentAwardOptionsOutstandingWeightedAverageExercisePrice	85.58
CY2019	us-gaap	Sharebased Compensation Arrangement By Sharebased Payment Award Options Outstanding Weighted Average Remaining Contractual Term2 SharebasedCompensationArrangementBySharebasedPaymentAwardOptionsOutstandingWeightedAverageRemainingContractualTerm2	P6Y
CY2019Q4	us-gaap	Share Based Compensation Arrangement By Share Based Payment Award Options Exercisable Number ShareBasedCompensationArrangementByShareBasedPaymentAwardOptionsExercisableNumber	400000	shares
CY2019Q4	us-gaap	Share Based Compensation Arrangement By Share Based Payment Award Options Exercisable Weighted Average Exercise Price ShareBasedCompensationArrangementByShareBasedPaymentAwardOptionsExercisableWeightedAverageExercisePrice	131.50
CY2019	us-gaap	Sharebased Compensation Arrangement By Sharebased Payment Award Options Exercisable Weighted Average Remaining Contractual Term1 SharebasedCompensationArrangementBySharebasedPaymentAwardOptionsExercisableWeightedAverageRemainingContractualTerm1	P3Y
CY2017	us-gaap	Sharebased Compensation Arrangement By Sharebased Payment Award Options Vested In Period Fair Value1 SharebasedCompensationArrangementBySharebasedPaymentAwardOptionsVestedInPeriodFairValue1	800000	USD
CY2018	us-gaap	Sharebased Compensation Arrangement By Sharebased Payment Award Options Vested In Period Fair Value1 SharebasedCompensationArrangementBySharebasedPaymentAwardOptionsVestedInPeriodFairValue1	1000000.0	USD
CY2019	us-gaap	Sharebased Compensation Arrangement By Sharebased Payment Award Options Vested In Period Fair Value1 SharebasedCompensationArrangementBySharebasedPaymentAwardOptionsVestedInPeriodFairValue1	34200000	USD
CY2017	us-gaap	Share Based Compensation Arrangement By Share Based Payment Award Options Exercises In Period Total Intrinsic Value ShareBasedCompensationArrangementByShareBasedPaymentAwardOptionsExercisesInPeriodTotalIntrinsicValue	50800000	USD
CY2018	us-gaap	Share Based Compensation Arrangement By Share Based Payment Award Options Exercises In Period Total Intrinsic Value ShareBasedCompensationArrangementByShareBasedPaymentAwardOptionsExercisesInPeriodTotalIntrinsicValue	8200000	USD
CY2019	us-gaap	Share Based Compensation Arrangement By Share Based Payment Award Options Exercises In Period Total Intrinsic Value ShareBasedCompensationArrangementByShareBasedPaymentAwardOptionsExercisesInPeriodTotalIntrinsicValue	200000	USD
CY2017	us-gaap	Proceeds From Stock Options Exercised ProceedsFromStockOptionsExercised	41900000	USD
CY2018	us-gaap	Proceeds From Stock Options Exercised ProceedsFromStockOptionsExercised	9700000	USD
CY2019	us-gaap	Proceeds From Stock Options Exercised ProceedsFromStockOptionsExercised	900000	USD
CY2019Q4	us-gaap	Sharebased Compensation Arrangement By Sharebased Payment Award Options Exercisable Intrinsic Value1 SharebasedCompensationArrangementBySharebasedPaymentAwardOptionsExercisableIntrinsicValue1	0	USD
CY2017	us-gaap	Share Based Compensation Arrangement By Share Based Payment Award Options Grants In Period Weighted Average Grant Date Fair Value ShareBasedCompensationArrangementByShareBasedPaymentAwardOptionsGrantsInPeriodWeightedAverageGrantDateFairValue	48.05
CY2018	us-gaap	Share Based Compensation Arrangement By Share Based Payment Award Options Grants In Period Weighted Average Grant Date Fair Value ShareBasedCompensationArrangementByShareBasedPaymentAwardOptionsGrantsInPeriodWeightedAverageGrantDateFairValue	48.64
CY2019	us-gaap	Share Based Compensation Arrangement By Share Based Payment Award Options Grants In Period Weighted Average Grant Date Fair Value ShareBasedCompensationArrangementByShareBasedPaymentAwardOptionsGrantsInPeriodWeightedAverageGrantDateFairValue	18.36
CY2017Q4	us-gaap	Redeemable Noncontrolling Interest Equity Carrying Amount RedeemableNoncontrollingInterestEquityCarryingAmount	811900000	USD
CY2018Q4	us-gaap	Redeemable Noncontrolling Interest Equity Carrying Amount RedeemableNoncontrollingInterestEquityCarryingAmount	833700000	USD
CY2018	amg	Noncontrolling Interest Increasedecrease Attributableto Consolidated Partnerships NoncontrollingInterestIncreasedecreaseAttributabletoConsolidatedPartnerships	51600000	USD
CY2019	amg	Noncontrolling Interest Increasedecrease Attributableto Consolidated Partnerships NoncontrollingInterestIncreasedecreaseAttributabletoConsolidatedPartnerships	-69400000	USD
CY2018	amg	Noncontrolling Interest Decreasefrom Transfersto Other Liabilities NoncontrollingInterestDecreasefromTransferstoOtherLiabilities	105400000	USD
CY2019	amg	Noncontrolling Interest Decreasefrom Transfersto Other Liabilities NoncontrollingInterestDecreasefromTransferstoOtherLiabilities	118600000	USD
CY2018	amg	Noncontrolling Interest Decreasefrom Transfersto Noncontrolling Interest Holders NoncontrollingInterestDecreasefromTransferstoNoncontrollingInterestHolders	44800000	USD
CY2019	amg	Noncontrolling Interest Decreasefrom Transfersto Noncontrolling Interest Holders NoncontrollingInterestDecreasefromTransferstoNoncontrollingInterestHolders	105000000.0	USD
CY2018	amg	Redeemable Noncontrolling Interest Change In Redemption Value RedeemableNoncontrollingInterestChangeInRedemptionValue	30800000	USD
CY2019	amg	Redeemable Noncontrolling Interest Change In Redemption Value RedeemableNoncontrollingInterestChangeInRedemptionValue	166000000.0	USD
CY2018Q4	us-gaap	Redeemable Noncontrolling Interest Equity Carrying Amount RedeemableNoncontrollingInterestEquityCarryingAmount	833700000	USD
CY2019Q4	us-gaap	Redeemable Noncontrolling Interest Equity Carrying Amount RedeemableNoncontrollingInterestEquityCarryingAmount	916700000	USD
CY2017	us-gaap	Payments Of Dividends Minority Interest PaymentsOfDividendsMinorityInterest	352200000	USD
CY2018	us-gaap	Payments Of Dividends Minority Interest PaymentsOfDividendsMinorityInterest	370500000	USD
CY2019	us-gaap	Payments Of Dividends Minority Interest PaymentsOfDividendsMinorityInterest	347900000	USD
CY2017	us-gaap	Payments To Acquire Businesses And Interest In Affiliates PaymentsToAcquireBusinessesAndInterestInAffiliates	174700000	USD
CY2018	us-gaap	Payments To Acquire Businesses And Interest In Affiliates PaymentsToAcquireBusinessesAndInterestInAffiliates	120000000.0	USD
CY2019	us-gaap	Payments To Acquire Businesses And Interest In Affiliates PaymentsToAcquireBusinessesAndInterestInAffiliates	146000000.0	USD
CY2017	us-gaap	Proceeds From Divestiture Of Businesses And Interests In Affiliates ProceedsFromDivestitureOfBusinessesAndInterestsInAffiliates	9000000.0	USD
CY2018	us-gaap	Proceeds From Divestiture Of Businesses And Interests In Affiliates ProceedsFromDivestitureOfBusinessesAndInterestsInAffiliates	6300000	USD
CY2017	us-gaap	Income Tax Expense Benefit IncomeTaxExpenseBenefit	58400000	USD
CY2018	us-gaap	Income Tax Expense Benefit IncomeTaxExpenseBenefit	181300000	USD
CY2019	us-gaap	Income Tax Expense Benefit IncomeTaxExpenseBenefit	2900000	USD
CY2019	us-gaap	Proceeds From Divestiture Of Businesses And Interests In Affiliates ProceedsFromDivestitureOfBusinessesAndInterestsInAffiliates	10500000	USD
CY2017	amg	Affiliate Equity Compensation Expense Including Portion Attributableto Noncontrolling Interest AffiliateEquityCompensationExpenseIncludingPortionAttributabletoNoncontrollingInterest	50000000.0	USD
CY2018	amg	Affiliate Equity Compensation Expense Including Portion Attributableto Noncontrolling Interest AffiliateEquityCompensationExpenseIncludingPortionAttributabletoNoncontrollingInterest	56400000	USD
CY2019	amg	Affiliate Equity Compensation Expense Including Portion Attributableto Noncontrolling Interest AffiliateEquityCompensationExpenseIncludingPortionAttributabletoNoncontrollingInterest	40500000	USD
CY2017	us-gaap	Net Income Loss NetIncomeLoss	689500000	USD
CY2018	us-gaap	Net Income Loss NetIncomeLoss	243600000	USD
CY2019	us-gaap	Net Income Loss NetIncomeLoss	15700000	USD
CY2017	amg	Adjustments To Additional Paid In Capital Increase Decrease In Carrying Amount Of Redeemable Noncontrolling Interests AdjustmentsToAdditionalPaidInCapitalIncreaseDecreaseInCarryingAmountOfRedeemableNoncontrollingInterests	1000000.0	USD
CY2018	amg	Adjustments To Additional Paid In Capital Increase Decrease In Carrying Amount Of Redeemable Noncontrolling Interests AdjustmentsToAdditionalPaidInCapitalIncreaseDecreaseInCarryingAmountOfRedeemableNoncontrollingInterests	5000000.0	USD
CY2019	amg	Adjustments To Additional Paid In Capital Increase Decrease In Carrying Amount Of Redeemable Noncontrolling Interests AdjustmentsToAdditionalPaidInCapitalIncreaseDecreaseInCarryingAmountOfRedeemableNoncontrollingInterests	3100000	USD
CY2017	amg	Adjustmentsto Additional Paidin Capital Decreasein Carrying Amountof Redeemable Noncontrolling Interests AdjustmentstoAdditionalPaidinCapitalDecreaseinCarryingAmountofRedeemableNoncontrollingInterests	116200000	USD
CY2018	amg	Adjustmentsto Additional Paidin Capital Decreasein Carrying Amountof Redeemable Noncontrolling Interests AdjustmentstoAdditionalPaidinCapitalDecreaseinCarryingAmountofRedeemableNoncontrollingInterests	67900000	USD
CY2019	amg	Adjustmentsto Additional Paidin Capital Decreasein Carrying Amountof Redeemable Noncontrolling Interests AdjustmentstoAdditionalPaidinCapitalDecreaseinCarryingAmountofRedeemableNoncontrollingInterests	50800000	USD
CY2017	amg	Increase Decrease In Equity Due To Profit Loss And Net Transfers With Noncontrolling Interests IncreaseDecreaseInEquityDueToProfitLossAndNetTransfersWithNoncontrollingInterests	572300000	USD
CY2018	amg	Increase Decrease In Equity Due To Profit Loss And Net Transfers With Noncontrolling Interests IncreaseDecreaseInEquityDueToProfitLossAndNetTransfersWithNoncontrollingInterests	170700000	USD
CY2019	amg	Increase Decrease In Equity Due To Profit Loss And Net Transfers With Noncontrolling Interests IncreaseDecreaseInEquityDueToProfitLossAndNetTransfersWithNoncontrollingInterests	-38200000	USD
CY2017	us-gaap	Defined Contribution Plan Employer Discretionary Contribution Amount DefinedContributionPlanEmployerDiscretionaryContributionAmount	20100000	USD
CY2018	us-gaap	Defined Contribution Plan Employer Discretionary Contribution Amount DefinedContributionPlanEmployerDiscretionaryContributionAmount	20800000	USD
CY2019	us-gaap	Defined Contribution Plan Employer Discretionary Contribution Amount DefinedContributionPlanEmployerDiscretionaryContributionAmount	19400000	USD
CY2017	us-gaap	Current Federal Tax Expense Benefit CurrentFederalTaxExpenseBenefit	109000000.0	USD
CY2018	us-gaap	Current Federal Tax Expense Benefit CurrentFederalTaxExpenseBenefit	52200000	USD
CY2019	us-gaap	Current Federal Tax Expense Benefit CurrentFederalTaxExpenseBenefit	-18200000	USD
CY2017	us-gaap	Current State And Local Tax Expense Benefit CurrentStateAndLocalTaxExpenseBenefit	18900000	USD
CY2018	us-gaap	Current State And Local Tax Expense Benefit CurrentStateAndLocalTaxExpenseBenefit	28600000	USD
CY2019	us-gaap	Current State And Local Tax Expense Benefit CurrentStateAndLocalTaxExpenseBenefit	-8800000	USD
CY2017	us-gaap	Current Foreign Tax Expense Benefit CurrentForeignTaxExpenseBenefit	54100000	USD
CY2018	us-gaap	Current Foreign Tax Expense Benefit CurrentForeignTaxExpenseBenefit	48600000	USD
CY2019	us-gaap	Current Foreign Tax Expense Benefit CurrentForeignTaxExpenseBenefit	85700000	USD
CY2017	us-gaap	Current Income Tax Expense Benefit CurrentIncomeTaxExpenseBenefit	182000000.0	USD
CY2018	us-gaap	Current Income Tax Expense Benefit CurrentIncomeTaxExpenseBenefit	129400000	USD
CY2019	us-gaap	Current Income Tax Expense Benefit CurrentIncomeTaxExpenseBenefit	58700000	USD
CY2017	us-gaap	Deferred Federal Income Tax Expense Benefit DeferredFederalIncomeTaxExpenseBenefit	-124900000	USD
CY2018	us-gaap	Deferred Federal Income Tax Expense Benefit DeferredFederalIncomeTaxExpenseBenefit	51300000	USD
CY2019	us-gaap	Deferred Federal Income Tax Expense Benefit DeferredFederalIncomeTaxExpenseBenefit	-23900000	USD
CY2017	us-gaap	Deferred State And Local Income Tax Expense Benefit DeferredStateAndLocalIncomeTaxExpenseBenefit	10400000	USD
CY2018	us-gaap	Deferred State And Local Income Tax Expense Benefit DeferredStateAndLocalIncomeTaxExpenseBenefit	13200000	USD
CY2019	us-gaap	Deferred State And Local Income Tax Expense Benefit DeferredStateAndLocalIncomeTaxExpenseBenefit	3400000	USD
CY2017	us-gaap	Deferred Foreign Income Tax Expense Benefit DeferredForeignIncomeTaxExpenseBenefit	-9100000	USD
CY2018	us-gaap	Deferred Foreign Income Tax Expense Benefit DeferredForeignIncomeTaxExpenseBenefit	-12600000	USD
CY2019	us-gaap	Deferred Foreign Income Tax Expense Benefit DeferredForeignIncomeTaxExpenseBenefit	-35300000	USD
CY2017	us-gaap	Deferred Income Tax Expense Benefit DeferredIncomeTaxExpenseBenefit	-123600000	USD
CY2018	us-gaap	Deferred Income Tax Expense Benefit DeferredIncomeTaxExpenseBenefit	51900000	USD
CY2019	us-gaap	Deferred Income Tax Expense Benefit DeferredIncomeTaxExpenseBenefit	-55800000	USD
CY2017	us-gaap	Income Tax Expense Benefit IncomeTaxExpenseBenefit	58400000	USD
CY2018	us-gaap	Income Tax Expense Benefit IncomeTaxExpenseBenefit	181300000	USD
CY2019	us-gaap	Income Tax Expense Benefit IncomeTaxExpenseBenefit	2900000	USD
CY2017	us-gaap	Income Loss From Continuing Operations Before Income Taxes Foreign IncomeLossFromContinuingOperationsBeforeIncomeTaxesForeign	310600000	USD
CY2018	us-gaap	Income Loss From Continuing Operations Before Income Taxes Foreign IncomeLossFromContinuingOperationsBeforeIncomeTaxesForeign	76300000	USD
CY2017	us-gaap	Income Loss From Continuing Operations Before Income Taxes Domestic IncomeLossFromContinuingOperationsBeforeIncomeTaxesDomestic	756500000	USD
CY2018	us-gaap	Income Loss From Continuing Operations Before Income Taxes Domestic IncomeLossFromContinuingOperationsBeforeIncomeTaxesDomestic	637300000	USD
CY2019	us-gaap	Income Loss From Continuing Operations Before Income Taxes Domestic IncomeLossFromContinuingOperationsBeforeIncomeTaxesDomestic	152200000	USD
CY2019	us-gaap	Income Loss From Continuing Operations Before Income Taxes Foreign IncomeLossFromContinuingOperationsBeforeIncomeTaxesForeign	155800000	USD
CY2017	us-gaap	Income Loss From Continuing Operations Before Income Taxes Minority Interest And Income Loss From Equity Method Investments IncomeLossFromContinuingOperationsBeforeIncomeTaxesMinorityInterestAndIncomeLossFromEquityMethodInvestments	1067100000	USD
CY2018	us-gaap	Income Loss From Continuing Operations Before Income Taxes Minority Interest And Income Loss From Equity Method Investments IncomeLossFromContinuingOperationsBeforeIncomeTaxesMinorityInterestAndIncomeLossFromEquityMethodInvestments	713600000	USD
CY2019	us-gaap	Income Loss From Continuing Operations Before Income Taxes Minority Interest And Income Loss From Equity Method Investments IncomeLossFromContinuingOperationsBeforeIncomeTaxesMinorityInterestAndIncomeLossFromEquityMethodInvestments	308000000.0	USD
CY2017	us-gaap	Effective Income Tax Rate Reconciliation At Federal Statutory Income Tax Rate EffectiveIncomeTaxRateReconciliationAtFederalStatutoryIncomeTaxRate	0.350
CY2018	us-gaap	Effective Income Tax Rate Reconciliation At Federal Statutory Income Tax Rate EffectiveIncomeTaxRateReconciliationAtFederalStatutoryIncomeTaxRate	0.210
CY2019	us-gaap	Effective Income Tax Rate Reconciliation At Federal Statutory Income Tax Rate EffectiveIncomeTaxRateReconciliationAtFederalStatutoryIncomeTaxRate	0.210
CY2017	us-gaap	Effective Income Tax Rate Reconciliation State And Local Income Taxes EffectiveIncomeTaxRateReconciliationStateAndLocalIncomeTaxes	0.027
CY2018	us-gaap	Effective Income Tax Rate Reconciliation State And Local Income Taxes EffectiveIncomeTaxRateReconciliationStateAndLocalIncomeTaxes	0.037
CY2019	us-gaap	Effective Income Tax Rate Reconciliation State And Local Income Taxes EffectiveIncomeTaxRateReconciliationStateAndLocalIncomeTaxes	0.035
CY2017	us-gaap	Effective Income Tax Rate Reconciliation Repatriation Of Foreign Earnings EffectiveIncomeTaxRateReconciliationRepatriationOfForeignEarnings	0.054
CY2018	us-gaap	Effective Income Tax Rate Reconciliation Repatriation Of Foreign Earnings EffectiveIncomeTaxRateReconciliationRepatriationOfForeignEarnings	-0.013
CY2019	us-gaap	Effective Income Tax Rate Reconciliation Repatriation Of Foreign Earnings EffectiveIncomeTaxRateReconciliationRepatriationOfForeignEarnings	4.712
CY2017	us-gaap	Effective Income Tax Rate Reconciliation Nondeductible Expense Other EffectiveIncomeTaxRateReconciliationNondeductibleExpenseOther	-0.007
CY2018	us-gaap	Effective Income Tax Rate Reconciliation Nondeductible Expense Other EffectiveIncomeTaxRateReconciliationNondeductibleExpenseOther	0.016
CY2019	us-gaap	Effective Income Tax Rate Reconciliation Nondeductible Expense Other EffectiveIncomeTaxRateReconciliationNondeductibleExpenseOther	2.406
CY2017	us-gaap	Effective Income Tax Rate Reconciliation Change In Enacted Tax Rate EffectiveIncomeTaxRateReconciliationChangeInEnactedTaxRate	-0.252
CY2018	us-gaap	Effective Income Tax Rate Reconciliation Change In Enacted Tax Rate EffectiveIncomeTaxRateReconciliationChangeInEnactedTaxRate	0
CY2019	us-gaap	Effective Income Tax Rate Reconciliation Change In Enacted Tax Rate EffectiveIncomeTaxRateReconciliationChangeInEnactedTaxRate	0
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CY2019	us-gaap	Effective Income Tax Rate Reconciliation Change In Deferred Tax Assets Valuation Allowance EffectiveIncomeTaxRateReconciliationChangeInDeferredTaxAssetsValuationAllowance	-1.072
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CY2018	us-gaap	Effective Income Tax Rate Reconciliation Equity In Earnings Losses Of Unconsolidated Subsidiary EffectiveIncomeTaxRateReconciliationEquityInEarningsLossesOfUnconsolidatedSubsidiary	0
CY2019	us-gaap	Effective Income Tax Rate Reconciliation Equity In Earnings Losses Of Unconsolidated Subsidiary EffectiveIncomeTaxRateReconciliationEquityInEarningsLossesOfUnconsolidatedSubsidiary	1.204
CY2017	us-gaap	Effective Income Tax Rate Reconciliation Nondeductible Expense Impairment Losses EffectiveIncomeTaxRateReconciliationNondeductibleExpenseImpairmentLosses	0
CY2018	us-gaap	Effective Income Tax Rate Reconciliation Nondeductible Expense Impairment Losses EffectiveIncomeTaxRateReconciliationNondeductibleExpenseImpairmentLosses	0.130
CY2019	us-gaap	Effective Income Tax Rate Reconciliation Nondeductible Expense Impairment Losses EffectiveIncomeTaxRateReconciliationNondeductibleExpenseImpairmentLosses	0
CY2017	us-gaap	Effective Income Tax Rate Reconciliation Tax Contingencies Domestic EffectiveIncomeTaxRateReconciliationTaxContingenciesDomestic	0.000
CY2018	us-gaap	Effective Income Tax Rate Reconciliation Tax Contingencies Domestic EffectiveIncomeTaxRateReconciliationTaxContingenciesDomestic	-0.010
CY2019	us-gaap	Effective Income Tax Rate Reconciliation Tax Contingencies Domestic EffectiveIncomeTaxRateReconciliationTaxContingenciesDomestic	-1.957
CY2017	us-gaap	Effective Income Tax Rate Reconciliation Other Adjustments EffectiveIncomeTaxRateReconciliationOtherAdjustments	-0.004
CY2018	us-gaap	Effective Income Tax Rate Reconciliation Other Adjustments EffectiveIncomeTaxRateReconciliationOtherAdjustments	0.009
CY2019	us-gaap	Effective Income Tax Rate Reconciliation Other Adjustments EffectiveIncomeTaxRateReconciliationOtherAdjustments	0.720
CY2017	amg	Income Tax Expense From Controlling Interest To Pretax Income From Continued Operations Attributable To Controlling Interest Ratio IncomeTaxExpenseFromControllingInterestToPretaxIncomeFromContinuedOperationsAttributableToControllingInterestRatio	0.068
CY2018	amg	Income Tax Expense From Controlling Interest To Pretax Income From Continued Operations Attributable To Controlling Interest Ratio IncomeTaxExpenseFromControllingInterestToPretaxIncomeFromContinuedOperationsAttributableToControllingInterestRatio	0.410
CY2019	amg	Income Tax Expense From Controlling Interest To Pretax Income From Continued Operations Attributable To Controlling Interest Ratio IncomeTaxExpenseFromControllingInterestToPretaxIncomeFromContinuedOperationsAttributableToControllingInterestRatio	-1.370
CY2017	us-gaap	Tax Cuts And Jobs Act Of2017 Incomplete Accounting Provisional Income Tax Expense Benefit TaxCutsAndJobsActOf2017IncompleteAccountingProvisionalIncomeTaxExpenseBenefit	-194100000	USD
CY2019Q4	us-gaap	Deferred Tax Assets Other DeferredTaxAssetsOther	2600000	USD
CY2018Q4	us-gaap	Deferred Tax Assets Gross DeferredTaxAssetsGross	77700000	USD
CY2019Q4	us-gaap	Deferred Tax Assets Gross DeferredTaxAssetsGross	92700000	USD
CY2018Q4	us-gaap	Deferred Tax Assets Valuation Allowance DeferredTaxAssetsValuationAllowance	24100000	USD
CY2018Q4	us-gaap	Deferred Tax Assets Tax Deferred Expense Compensation And Benefits DeferredTaxAssetsTaxDeferredExpenseCompensationAndBenefits	18000000.0	USD
CY2019Q4	us-gaap	Deferred Tax Assets Tax Deferred Expense Compensation And Benefits DeferredTaxAssetsTaxDeferredExpenseCompensationAndBenefits	13800000	USD
CY2018Q4	us-gaap	Deferred Tax Assets Operating Loss Carryforwards State And Local DeferredTaxAssetsOperatingLossCarryforwardsStateAndLocal	18200000	USD
CY2019Q4	us-gaap	Deferred Tax Assets Operating Loss Carryforwards State And Local DeferredTaxAssetsOperatingLossCarryforwardsStateAndLocal	15900000	USD
CY2018Q4	us-gaap	Deferred Tax Assets Operating Loss Carryforwards Foreign DeferredTaxAssetsOperatingLossCarryforwardsForeign	16700000	USD
CY2019Q4	us-gaap	Deferred Tax Assets Operating Loss Carryforwards Foreign DeferredTaxAssetsOperatingLossCarryforwardsForeign	17700000	USD
CY2018Q4	amg	Deferred Tax Assets Tax Benefit On Uncertain Tax Positions DeferredTaxAssetsTaxBenefitOnUncertainTaxPositions	10900000	USD
CY2019Q4	amg	Deferred Tax Assets Tax Benefit On Uncertain Tax Positions DeferredTaxAssetsTaxBenefitOnUncertainTaxPositions	27400000	USD
CY2018Q4	us-gaap	Deferred Tax Assets Deferred Income DeferredTaxAssetsDeferredIncome	8800000	USD
CY2019Q4	us-gaap	Deferred Tax Assets Deferred Income DeferredTaxAssetsDeferredIncome	3000000.0	USD
CY2019Q4	amg	Deferred Tax Assets Operating Lease Liability DeferredTaxAssetsOperatingLeaseLiability	12300000	USD
CY2018Q4	us-gaap	Deferred Tax Assets Other DeferredTaxAssetsOther	5100000	USD
CY2019Q4	us-gaap	Deferred Tax Assets Valuation Allowance DeferredTaxAssetsValuationAllowance	16900000	USD
CY2018Q4	us-gaap	Deferred Tax Assets Net DeferredTaxAssetsNet	53600000	USD
CY2019Q4	us-gaap	Deferred Tax Assets Net DeferredTaxAssetsNet	75800000	USD
CY2018Q4	us-gaap	Deferred Tax Liabilities Goodwill And Intangible Assets Intangible Assets DeferredTaxLiabilitiesGoodwillAndIntangibleAssetsIntangibleAssets	337100000	USD
CY2019Q4	us-gaap	Deferred Tax Liabilities Goodwill And Intangible Assets Intangible Assets DeferredTaxLiabilitiesGoodwillAndIntangibleAssetsIntangibleAssets	293700000	USD
CY2018Q4	amg	Deferred Tax Liabilities Nondeductible Intangible Assets Amortization DeferredTaxLiabilitiesNondeductibleIntangibleAssetsAmortization	141000000.0	USD
CY2019Q4	amg	Deferred Tax Liabilities Nondeductible Intangible Assets Amortization DeferredTaxLiabilitiesNondeductibleIntangibleAssetsAmortization	110900000	USD
CY2018Q4	amg	Deferred Tax Liabilities Convertible Securities Interest DeferredTaxLiabilitiesConvertibleSecuritiesInterest	84500000	USD
CY2019Q4	amg	Deferred Tax Liabilities Convertible Securities Interest DeferredTaxLiabilitiesConvertibleSecuritiesInterest	91600000	USD
CY2019Q4	us-gaap	Deferred Tax Liabilities Leasing Arrangements DeferredTaxLiabilitiesLeasingArrangements	10300000	USD
CY2018Q4	us-gaap	Deferred Tax Liabilities Other DeferredTaxLiabilitiesOther	2600000	USD
CY2019Q4	us-gaap	Deferred Tax Liabilities Other DeferredTaxLiabilitiesOther	4100000	USD
CY2018Q4	us-gaap	Deferred Income Tax Liabilities DeferredIncomeTaxLiabilities	565200000	USD
CY2019Q4	us-gaap	Deferred Income Tax Liabilities DeferredIncomeTaxLiabilities	510600000	USD
CY2018Q4	us-gaap	Deferred Tax Liabilities DeferredTaxLiabilities	511600000	USD
CY2019Q4	us-gaap	Deferred Tax Liabilities DeferredTaxLiabilities	434800000	USD
CY2019	amg	Operating Loss Carryforwards Foreign Expiration Period OperatingLossCarryforwardsForeignExpirationPeriod	P20Y
CY2019Q4	us-gaap	Undistributed Earnings Of Foreign Subsidiaries UndistributedEarningsOfForeignSubsidiaries	249400000	USD
CY2016Q4	us-gaap	Unrecognized Tax Benefits UnrecognizedTaxBenefits	26800000	USD
CY2017Q4	us-gaap	Unrecognized Tax Benefits UnrecognizedTaxBenefits	32400000	USD
CY2018Q4	us-gaap	Unrecognized Tax Benefits UnrecognizedTaxBenefits	33100000	USD
CY2017	us-gaap	Unrecognized Tax Benefits Increases Resulting From Current Period Tax Positions UnrecognizedTaxBenefitsIncreasesResultingFromCurrentPeriodTaxPositions	6000000.0	USD
CY2018	us-gaap	Unrecognized Tax Benefits Increases Resulting From Current Period Tax Positions UnrecognizedTaxBenefitsIncreasesResultingFromCurrentPeriodTaxPositions	2400000	USD
CY2019	us-gaap	Unrecognized Tax Benefits Increases Resulting From Current Period Tax Positions UnrecognizedTaxBenefitsIncreasesResultingFromCurrentPeriodTaxPositions	39800000	USD
CY2017	us-gaap	Unrecognized Tax Benefits Increases Resulting From Prior Period Tax Positions UnrecognizedTaxBenefitsIncreasesResultingFromPriorPeriodTaxPositions	1500000	USD
CY2018	us-gaap	Unrecognized Tax Benefits Increases Resulting From Prior Period Tax Positions UnrecognizedTaxBenefitsIncreasesResultingFromPriorPeriodTaxPositions	8400000	USD
CY2019	us-gaap	Unrecognized Tax Benefits Increases Resulting From Prior Period Tax Positions UnrecognizedTaxBenefitsIncreasesResultingFromPriorPeriodTaxPositions	3200000	USD
CY2017	us-gaap	Unrecognized Tax Benefits Decreases Resulting From Prior Period Tax Positions UnrecognizedTaxBenefitsDecreasesResultingFromPriorPeriodTaxPositions	0	USD
CY2018	us-gaap	Unrecognized Tax Benefits Decreases Resulting From Prior Period Tax Positions UnrecognizedTaxBenefitsDecreasesResultingFromPriorPeriodTaxPositions	2000000.0	USD
CY2019	us-gaap	Unrecognized Tax Benefits Decreases Resulting From Prior Period Tax Positions UnrecognizedTaxBenefitsDecreasesResultingFromPriorPeriodTaxPositions	3500000	USD
CY2017	us-gaap	Unrecognized Tax Benefits Reductions Resulting From Lapse Of Applicable Statute Of Limitations UnrecognizedTaxBenefitsReductionsResultingFromLapseOfApplicableStatuteOfLimitations	2300000	USD
CY2018	us-gaap	Unrecognized Tax Benefits Reductions Resulting From Lapse Of Applicable Statute Of Limitations UnrecognizedTaxBenefitsReductionsResultingFromLapseOfApplicableStatuteOfLimitations	6300000	USD
CY2019	us-gaap	Unrecognized Tax Benefits Reductions Resulting From Lapse Of Applicable Statute Of Limitations UnrecognizedTaxBenefitsReductionsResultingFromLapseOfApplicableStatuteOfLimitations	4000000.0	USD
CY2017	us-gaap	Unrecognized Tax Benefits Decreases Resulting From Settlements With Taxing Authorities UnrecognizedTaxBenefitsDecreasesResultingFromSettlementsWithTaxingAuthorities	0	USD
CY2018	us-gaap	Unrecognized Tax Benefits Decreases Resulting From Settlements With Taxing Authorities UnrecognizedTaxBenefitsDecreasesResultingFromSettlementsWithTaxingAuthorities	1300000	USD
CY2019	us-gaap	Unrecognized Tax Benefits Decreases Resulting From Settlements With Taxing Authorities UnrecognizedTaxBenefitsDecreasesResultingFromSettlementsWithTaxingAuthorities	400000	USD
CY2017	amg	Unrecognized Tax Benefits Increase Decrease Relatedto Foreign Exchange Rates UnrecognizedTaxBenefitsIncreaseDecreaseRelatedtoForeignExchangeRates	400000	USD
CY2018	amg	Unrecognized Tax Benefits Increase Decrease Relatedto Foreign Exchange Rates UnrecognizedTaxBenefitsIncreaseDecreaseRelatedtoForeignExchangeRates	-500000	USD
CY2019	amg	Unrecognized Tax Benefits Increase Decrease Relatedto Foreign Exchange Rates UnrecognizedTaxBenefitsIncreaseDecreaseRelatedtoForeignExchangeRates	-2800000	USD
CY2017Q4	us-gaap	Unrecognized Tax Benefits UnrecognizedTaxBenefits	32400000	USD
CY2018Q4	us-gaap	Unrecognized Tax Benefits UnrecognizedTaxBenefits	33100000	USD
CY2019Q4	us-gaap	Unrecognized Tax Benefits UnrecognizedTaxBenefits	65400000	USD
CY2017Q4	us-gaap	Unrecognized Tax Benefits That Would Impact Effective Tax Rate UnrecognizedTaxBenefitsThatWouldImpactEffectiveTaxRate	32400000	USD
CY2018Q4	us-gaap	Unrecognized Tax Benefits That Would Impact Effective Tax Rate UnrecognizedTaxBenefitsThatWouldImpactEffectiveTaxRate	33100000	USD
CY2019Q4	us-gaap	Unrecognized Tax Benefits That Would Impact Effective Tax Rate UnrecognizedTaxBenefitsThatWouldImpactEffectiveTaxRate	65400000	USD
CY2017	us-gaap	Unrecognized Tax Benefits Income Tax Penalties And Interest Expense UnrecognizedTaxBenefitsIncomeTaxPenaltiesAndInterestExpense	300000	USD
CY2018	us-gaap	Unrecognized Tax Benefits Income Tax Penalties And Interest Expense UnrecognizedTaxBenefitsIncomeTaxPenaltiesAndInterestExpense	400000	USD
CY2019	us-gaap	Unrecognized Tax Benefits Income Tax Penalties And Interest Expense UnrecognizedTaxBenefitsIncomeTaxPenaltiesAndInterestExpense	8400000	USD
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CY2019Q4	us-gaap	Unrecognized Tax Benefits Income Tax Penalties And Interest Accrued UnrecognizedTaxBenefitsIncomeTaxPenaltiesAndInterestAccrued	10500000	USD
CY2017	us-gaap	Net Income Loss NetIncomeLoss	689500000	USD
CY2018	us-gaap	Net Income Loss NetIncomeLoss	243600000	USD
CY2019	us-gaap	Net Income Loss NetIncomeLoss	15700000	USD
CY2017	us-gaap	Interest On Convertible Debt Net Of Tax InterestOnConvertibleDebtNetOfTax	15500000	USD
CY2018	us-gaap	Interest On Convertible Debt Net Of Tax InterestOnConvertibleDebtNetOfTax	0	USD
CY2019	us-gaap	Interest On Convertible Debt Net Of Tax InterestOnConvertibleDebtNetOfTax	0	USD
CY2017	us-gaap	Net Income Loss Available To Common Stockholders Diluted NetIncomeLossAvailableToCommonStockholdersDiluted	705000000.0	USD
CY2018	us-gaap	Net Income Loss Available To Common Stockholders Diluted NetIncomeLossAvailableToCommonStockholdersDiluted	243600000	USD
CY2019	us-gaap	Net Income Loss Available To Common Stockholders Diluted NetIncomeLossAvailableToCommonStockholdersDiluted	15700000	USD
CY2017	us-gaap	Weighted Average Number Of Shares Outstanding Basic WeightedAverageNumberOfSharesOutstandingBasic	56000000.0	shares
CY2018	us-gaap	Weighted Average Number Of Shares Outstanding Basic WeightedAverageNumberOfSharesOutstandingBasic	53600000	shares
CY2019	us-gaap	Weighted Average Number Of Shares Outstanding Basic WeightedAverageNumberOfSharesOutstandingBasic	50500000	shares
CY2017	us-gaap	Incremental Common Shares Attributable To Share Based Payment Arrangements IncrementalCommonSharesAttributableToShareBasedPaymentArrangements	400000	shares
CY2018	us-gaap	Incremental Common Shares Attributable To Share Based Payment Arrangements IncrementalCommonSharesAttributableToShareBasedPaymentArrangements	200000	shares
CY2019	us-gaap	Incremental Common Shares Attributable To Share Based Payment Arrangements IncrementalCommonSharesAttributableToShareBasedPaymentArrangements	100000	shares
CY2017	us-gaap	Incremental Common Shares Attributable To Conversion Of Debt Securities IncrementalCommonSharesAttributableToConversionOfDebtSecurities	2200000	shares
CY2018	us-gaap	Incremental Common Shares Attributable To Conversion Of Debt Securities IncrementalCommonSharesAttributableToConversionOfDebtSecurities	0	shares
CY2019	us-gaap	Incremental Common Shares Attributable To Conversion Of Debt Securities IncrementalCommonSharesAttributableToConversionOfDebtSecurities	0	shares
CY2017	us-gaap	Weighted Average Number Of Diluted Shares Outstanding WeightedAverageNumberOfDilutedSharesOutstanding	58600000	shares
CY2018	us-gaap	Weighted Average Number Of Diluted Shares Outstanding WeightedAverageNumberOfDilutedSharesOutstanding	53800000	shares
CY2019	us-gaap	Weighted Average Number Of Diluted Shares Outstanding WeightedAverageNumberOfDilutedSharesOutstanding	50600000	shares
CY2017	us-gaap	Other Comprehensive Income Loss Before Tax OtherComprehensiveIncomeLossBeforeTax	112300000	USD
CY2017	us-gaap	Other Comprehensive Income Loss Tax OtherComprehensiveIncomeLossTax	-7200000	USD
CY2017	us-gaap	Other Comprehensive Income Loss Net Of Tax OtherComprehensiveIncomeLossNetOfTax	119500000	USD
CY2018	us-gaap	Other Comprehensive Income Loss Before Tax OtherComprehensiveIncomeLossBeforeTax	-87100000	USD
CY2018	us-gaap	Other Comprehensive Income Loss Tax OtherComprehensiveIncomeLossTax	15100000	USD
CY2018	us-gaap	Other Comprehensive Income Loss Net Of Tax OtherComprehensiveIncomeLossNetOfTax	-102200000	USD
CY2019	us-gaap	Other Comprehensive Income Loss Before Tax OtherComprehensiveIncomeLossBeforeTax	-9700000	USD
CY2019	us-gaap	Other Comprehensive Income Loss Tax OtherComprehensiveIncomeLossTax	-22300000	USD
CY2019	us-gaap	Other Comprehensive Income Loss Net Of Tax OtherComprehensiveIncomeLossNetOfTax	12600000	USD
CY2018Q4	us-gaap	Profit Loss ProfitLoss	-98800000	USD
CY2018Q1	us-gaap	Net Income Loss NetIncomeLoss	153000000.0	USD
CY2018Q1	us-gaap	Revenue From Contract With Customer Excluding Assessed Tax RevenueFromContractWithCustomerExcludingAssessedTax	612500000	USD
CY2018Q2	us-gaap	Revenue From Contract With Customer Excluding Assessed Tax RevenueFromContractWithCustomerExcludingAssessedTax	600200000	USD
CY2018Q3	us-gaap	Revenue From Contract With Customer Excluding Assessed Tax RevenueFromContractWithCustomerExcludingAssessedTax	601300000	USD
CY2018Q4	us-gaap	Revenue From Contract With Customer Excluding Assessed Tax RevenueFromContractWithCustomerExcludingAssessedTax	564400000	USD
CY2018Q1	us-gaap	Income Loss From Continuing Operations Before Income Taxes Extraordinary Items Noncontrolling Interest IncomeLossFromContinuingOperationsBeforeIncomeTaxesExtraordinaryItemsNoncontrollingInterest	287500000	USD
CY2018Q2	us-gaap	Income Loss From Continuing Operations Before Income Taxes Extraordinary Items Noncontrolling Interest IncomeLossFromContinuingOperationsBeforeIncomeTaxesExtraordinaryItemsNoncontrollingInterest	239300000	USD
CY2018Q3	us-gaap	Income Loss From Continuing Operations Before Income Taxes Extraordinary Items Noncontrolling Interest IncomeLossFromContinuingOperationsBeforeIncomeTaxesExtraordinaryItemsNoncontrollingInterest	250400000	USD
CY2018Q4	us-gaap	Income Loss From Continuing Operations Before Income Taxes Extraordinary Items Noncontrolling Interest IncomeLossFromContinuingOperationsBeforeIncomeTaxesExtraordinaryItemsNoncontrollingInterest	-63600000	USD
CY2018Q1	us-gaap	Profit Loss ProfitLoss	224000000.0	USD
CY2018Q2	us-gaap	Profit Loss ProfitLoss	205200000	USD
CY2018Q3	us-gaap	Profit Loss ProfitLoss	201900000	USD
CY2018Q2	us-gaap	Net Income Loss NetIncomeLoss	117000000.0	USD
CY2018Q3	us-gaap	Net Income Loss NetIncomeLoss	124900000	USD
CY2018Q4	us-gaap	Net Income Loss NetIncomeLoss	-151300000	USD
CY2018Q1	us-gaap	Earnings Per Share Diluted EarningsPerShareDiluted	2.77
CY2018Q2	us-gaap	Earnings Per Share Diluted EarningsPerShareDiluted	2.16
CY2018Q3	us-gaap	Earnings Per Share Diluted EarningsPerShareDiluted	2.34
CY2018Q4	us-gaap	Earnings Per Share Diluted EarningsPerShareDiluted	-2.88
CY2019Q1	us-gaap	Revenue From Contract With Customer Excluding Assessed Tax RevenueFromContractWithCustomerExcludingAssessedTax	543100000	USD
CY2019Q2	us-gaap	Revenue From Contract With Customer Excluding Assessed Tax RevenueFromContractWithCustomerExcludingAssessedTax	592000000.0	USD
CY2019Q3	us-gaap	Revenue From Contract With Customer Excluding Assessed Tax RevenueFromContractWithCustomerExcludingAssessedTax	549000000.0	USD
CY2019Q4	us-gaap	Revenue From Contract With Customer Excluding Assessed Tax RevenueFromContractWithCustomerExcludingAssessedTax	555500000	USD
CY2019Q1	us-gaap	Income Loss From Continuing Operations Before Income Taxes Extraordinary Items Noncontrolling Interest IncomeLossFromContinuingOperationsBeforeIncomeTaxesExtraordinaryItemsNoncontrollingInterest	-194800000	USD
CY2019Q2	us-gaap	Income Loss From Continuing Operations Before Income Taxes Extraordinary Items Noncontrolling Interest IncomeLossFromContinuingOperationsBeforeIncomeTaxesExtraordinaryItemsNoncontrollingInterest	215900000	USD
CY2019Q3	us-gaap	Income Loss From Continuing Operations Before Income Taxes Extraordinary Items Noncontrolling Interest IncomeLossFromContinuingOperationsBeforeIncomeTaxesExtraordinaryItemsNoncontrollingInterest	192600000	USD
CY2019Q4	us-gaap	Income Loss From Continuing Operations Before Income Taxes Extraordinary Items Noncontrolling Interest IncomeLossFromContinuingOperationsBeforeIncomeTaxesExtraordinaryItemsNoncontrollingInterest	94300000	USD
CY2019Q1	us-gaap	Profit Loss ProfitLoss	-133000000.0	USD
CY2019Q2	us-gaap	Profit Loss ProfitLoss	180100000	USD
CY2019Q3	us-gaap	Profit Loss ProfitLoss	162100000	USD
CY2019Q4	us-gaap	Profit Loss ProfitLoss	95900000	USD
CY2019Q1	us-gaap	Net Income Loss NetIncomeLoss	-200800000	USD
CY2019Q2	us-gaap	Net Income Loss NetIncomeLoss	107700000	USD
CY2019Q3	us-gaap	Net Income Loss NetIncomeLoss	86300000	USD
CY2019Q4	us-gaap	Net Income Loss NetIncomeLoss	22500000	USD
CY2019Q1	us-gaap	Earnings Per Share Diluted EarningsPerShareDiluted	-3.87
CY2019Q2	us-gaap	Earnings Per Share Diluted EarningsPerShareDiluted	2.11
CY2019Q3	us-gaap	Earnings Per Share Diluted EarningsPerShareDiluted	1.71
CY2019Q4	us-gaap	Earnings Per Share Diluted EarningsPerShareDiluted	0.46
CY2017	us-gaap	Revenue From Contract With Customer Excluding Assessed Tax RevenueFromContractWithCustomerExcludingAssessedTax	2305000000.0	USD
CY2018	us-gaap	Revenue From Contract With Customer Excluding Assessed Tax RevenueFromContractWithCustomerExcludingAssessedTax	2378400000	USD
CY2019	us-gaap	Revenue From Contract With Customer Excluding Assessed Tax RevenueFromContractWithCustomerExcludingAssessedTax	2239600000	USD
CY2018Q4	us-gaap	Property Plant And Equipment Net PropertyPlantAndEquipmentNet	104300000	USD
CY2019Q4	us-gaap	Property Plant And Equipment Net PropertyPlantAndEquipmentNet	92300000	USD

Files In Submission

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$AMG
AFFILIATED MANAGERS GROUP, INC. Stock $amg

2019 Q4 Form 10-K Financial Statement

#000100443420000011 Filed on February 28, 2020

Income Statement

Balance Sheet

Cashflow Statement

Facts In Submission

Files In Submission

$AMG AFFILIATED MANAGERS GROUP, INC. Stock $amg

2019 Q4 Form 10-K Financial Statement

#000100443420000011 Filed on February 28, 2020

Income Statement

Balance Sheet

Cashflow Statement

Facts In Submission

Files In Submission

$AMG
AFFILIATED MANAGERS GROUP, INC. Stock $amg