$AMG
AFFILIATED MANAGERS GROUP, INC. Stock $amg

$amg Overview Financials Valuation SEC Filings Company Website

2024 Q1 Form 10-K Financial Statement

#000100443424000010 Filed on February 16, 2024

Income Statement

Concept	2024 Q1	2023 Q4	2023
Revenue	$499.9M	$502.7M	$2.058B
YoY Change	-3.38%	-6.86%	-11.67%
Cost Of Revenue
YoY Change
Gross Profit
YoY Change
Gross Profit Margin
Selling, General & Admin	$91.70M	$329.3M	$1.266B
YoY Change	-71.29%	-14.31%	228.33%
% of Gross Profit
Research & Development
YoY Change
% of Gross Profit
Depreciation & Amortization	$10.30M	$13.80M	$61.30M
YoY Change	-36.42%	-14.29%	-9.05%
% of Gross Profit
Operating Expenses	$381.3M	$352.7M	$1.373B
YoY Change	8.94%	-16.58%	-17.97%
Operating Profit
YoY Change
Interest Expense	$29.90M	$124.1M	$273.3M
YoY Change	-54.77%	-58.65%	138.9%
% of Operating Profit
Other Income/Expense, Net		$0.00	$133.1M
YoY Change		-100.0%	-79.26%
Pretax Income	$254.1M	$274.1M	$1.091B
YoY Change	8.82%	-74.11%	-37.51%
Income Tax	$55.40M	$29.80M	$185.3M
% Of Pretax Income	21.8%	10.87%	16.98%
Net Earnings	$149.8M	$196.2M	$672.9M
YoY Change	11.38%	-74.78%	-41.28%
Net Earnings / Revenue	29.97%	39.03%	32.7%
Basic Earnings Per Share	$4.56		$19.18
Diluted Earnings Per Share	$4.14	$4.75	$15.95
COMMON SHARES
Basic Shares Outstanding	32.79M shares	33.81M shares	35.10M shares
Diluted Shares Outstanding	40.10M shares		42.20M shares

Balance Sheet

Concept	2024 Q1	2023 Q4	2023
SHORT-TERM ASSETS
Cash & Short-Term Investments	$1.142B	$813.6M	$813.6M
YoY Change	37.16%	-29.01%	89.56%
Cash & Equivalents	$793.4M	$813.6M	$813.6M
Short-Term Investments	$348.9M	$461.0M
Other Short-Term Assets
YoY Change
Inventory
Prepaid Expenses
Receivables	$525.7M	$368.4M	$368.4M
Other Receivables	$0.00	$0.00	$0.00
Total Short-Term Assets	$1.319B	$1.182B	$1.182B
YoY Change	6.26%	58.62%	58.62%
LONG-TERM ASSETS
Property, Plant & Equipment	$65.60M	$67.30M	$67.30M
YoY Change	-2.24%	-1.75%	-1.75%
Goodwill	$2.518B	$2.524B
YoY Change	-4.96%	-4.72%
Intangibles	$1.802B	$1.812B
YoY Change	-3.42%	-3.39%
Long-Term Investments	$93.60M	$3.230B	$3.230B
YoY Change	-96.66%	3575.09%	-1.45%
Other Assets
YoY Change
Total Long-Term Assets	$7.706B	$7.878B	$7.878B
YoY Change	0.67%	-3.17%	-3.17%
TOTAL ASSETS
Total Short-Term Assets	$1.319B	$1.182B	$1.182B
Total Long-Term Assets	$7.706B	$7.878B	$7.878B
Total Assets	$9.025B	$9.060B	$9.060B
YoY Change	1.45%	2.01%	2.01%
SHORT-TERM LIABILITIES
YoY Change
Accounts Payable	$634.1M	$628.5M	$628.5M
YoY Change	-1.74%
Accrued Expenses		$566.2M	$566.2M
YoY Change		2.22%	2.22%
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	$634.1M	$628.5M	$628.5M
YoY Change	-1.74%	-19.25%	-19.25%
LONG-TERM LIABILITIES
Long-Term Debt	$2.525B	$2.538B	$2.538B
YoY Change	-0.43%	0.09%	0.09%
Other Long-Term Liabilities	$464.6M	$466.3M	$466.3M
YoY Change	-4.34%	1.0%	1.0%
Total Long-Term Liabilities	$2.990B	$3.004B	$3.004B
YoY Change	-1.06%	0.23%	0.23%
TOTAL LIABILITIES
Total Short-Term Liabilities	$634.1M	$628.5M	$628.5M
Total Long-Term Liabilities	$2.990B	$3.004B	$3.004B
Total Liabilities	$4.111B	$5.472B	$5.472B
YoY Change	-26.9%	29.05%	-3.17%
SHAREHOLDERS EQUITY
Retained Earnings	$6.539B	$6.390B
YoY Change	11.74%	11.74%
Common Stock	$712.7M	$742.0M
YoY Change	26.25%	6.59%
Preferred Stock
YoY Change
Treasury Stock (at cost)	$3.504B	$3.376B
YoY Change	18.11%	13.27%
Treasury Stock Shares
Shareholders Equity	$3.590B	$3.588B	$3.588B
YoY Change
Total Liabilities & Shareholders Equity	$9.025B	$9.060B	$9.060B
YoY Change	1.45%	2.01%	2.01%

Cashflow Statement

Concept	2024 Q1	2023 Q4	2023
OPERATING ACTIVITIES
Net Income	$149.8M	$196.2M	$672.9M
YoY Change	11.38%	-74.78%	-41.28%
Depreciation, Depletion And Amortization	$10.30M	$13.80M	$61.30M
YoY Change	-36.42%	-14.29%	-9.05%
Cash From Operating Activities	$209.2M	$255.0M	$874.3M
YoY Change	-10.9%	-1.43%	-17.1%
INVESTING ACTIVITIES
Capital Expenditures	$1.000M	$5.800M	$12.40M
YoY Change	-47.37%	152.17%	8.77%
Acquisitions
YoY Change
Other Investing Activities	$75.50M	-$207.6M	$276.9M
YoY Change	-73.96%	-230.57%	-381.12%
Cash From Investing Activities	$74.50M	-$213.4M	$264.5M
YoY Change	-74.13%	-236.18%	-340.67%
FINANCING ACTIVITIES
Cash Dividend Paid
YoY Change
Common Stock Issuance & Retirement, Net
YoY Change
Debt Paid & Issued, Net	$450.0M		$25.00M
YoY Change	1700.0%		-58.88%
Cash From Financing Activities	-$302.3M	-234.3M	-$758.3M
YoY Change	158.6%	-62.44%	-45.95%
NET CHANGE
Cash From Operating Activities	$209.2M	255.0M	$874.3M
Cash From Investing Activities	$74.50M	-213.4M	$264.5M
Cash From Financing Activities	-$302.3M	-234.3M	-$758.3M
Net Change In Cash	-$20.20M	-192.7M	$387.4M
YoY Change	-104.94%	-7.53%	-180.59%
FREE CASH FLOW
Cash From Operating Activities	$209.2M	$255.0M	$874.3M
Capital Expenditures	$1.000M	$5.800M	$12.40M
Free Cash Flow	$208.2M	$249.2M	$861.9M
YoY Change	-10.61%	-2.81%	-17.39%

Facts In Submission

Frame	Concept Type	Concept / XBRL Key	Value	Unit
CY2021	us-gaap	Income Loss From Equity Method Investments IncomeLossFromEquityMethodInvestments	242500000	usd
CY2021	us-gaap	Income Tax Expense Benefit IncomeTaxExpenseBenefit	251000000.0	usd
CY2022	us-gaap	Net Income Loss NetIncomeLoss	1145900000	usd
CY2023	us-gaap	Net Income Loss NetIncomeLoss	672900000	usd
CY2023	us-gaap	Weighted Average Number Of Shares Outstanding Basic WeightedAverageNumberOfSharesOutstandingBasic	35100000	shares
CY2021Q4	us-gaap	Equity Securities Without Readily Determinable Fair Value Amount EquitySecuritiesWithoutReadilyDeterminableFairValueAmount	50400000	usd
CY2022Q4	us-gaap	Equity Securities Without Readily Determinable Fair Value Amount EquitySecuritiesWithoutReadilyDeterminableFairValueAmount	50400000	usd
CY2022Q4	us-gaap	Other Investments OtherInvestments	421600000	usd
CY2022Q4	us-gaap	Other Investments OtherInvestments	421600000	usd
CY2023	amg	Equity Securities Without Readily Determinable Fair Value Purchases And Commitments EquitySecuritiesWithoutReadilyDeterminableFairValuePurchasesAndCommitments	0	usd
CY2023	amg	Equity Securities Without Readily Determinable Fair Value Sales And Distributions EquitySecuritiesWithoutReadilyDeterminableFairValueSalesAndDistributions	0	usd
CY2023	amg	Other Investments Sales OtherInvestmentsSales	57400000	usd
CY2023	dei	Entity Central Index Key EntityCentralIndexKey	0001004434
CY2023	dei	Amendment Flag AmendmentFlag	false
CY2023	dei	Document Fiscal Period Focus DocumentFiscalPeriodFocus	FY
CY2021	us-gaap	Accounting Standards Update Extensible List AccountingStandardsUpdateExtensibleList	http://fasb.org/us-gaap/2023#AccountingStandardsUpdate202006Member
CY2023	dei	Document Annual Report DocumentAnnualReport	true
CY2023	dei	Current Fiscal Year End Date CurrentFiscalYearEndDate	--12-31
CY2023	dei	Document Transition Report DocumentTransitionReport	false
CY2023	dei	Entity File Number EntityFileNumber	001-13459
CY2023	dei	Entity Registrant Name EntityRegistrantName	AFFILIATED MANAGERS GROUP, INC.
CY2023	dei	Entity Incorporation State Country Code EntityIncorporationStateCountryCode	DE
CY2023	dei	Entity Tax Identification Number EntityTaxIdentificationNumber	04-3218510
CY2023	dei	Entity Address Address Line1 EntityAddressAddressLine1	777 South Flagler Drive
CY2023	dei	Entity Address City Or Town EntityAddressCityOrTown	West Palm Beach
CY2023	dei	Entity Address State Or Province EntityAddressStateOrProvince	FL
CY2023	dei	Entity Address Postal Zip Code EntityAddressPostalZipCode	33401
CY2023	dei	City Area Code CityAreaCode	800
CY2023	dei	Local Phone Number LocalPhoneNumber	345-1100
CY2023	dei	Entity Well Known Seasoned Issuer EntityWellKnownSeasonedIssuer	Yes
CY2023	dei	Entity Voluntary Filers EntityVoluntaryFilers	No
CY2023	dei	Icfr Auditor Attestation Flag IcfrAuditorAttestationFlag	true
CY2023	dei	Document Fin Stmt Error Correction Flag DocumentFinStmtErrorCorrectionFlag	false
CY2023	dei	Entity Shell Company EntityShellCompany	false
CY2023	dei	Document Fiscal Year Focus DocumentFiscalYearFocus	2023
CY2023	dei	Document Fiscal Year Focus DocumentFiscalYearFocus	2023
CY2023Q2	dei	Entity Public Float EntityPublicFloat	5227465462	usd
CY2024Q1	dei	Entity Common Stock Shares Outstanding EntityCommonStockSharesOutstanding	32794127	shares
CY2023	dei	Auditor Firm AuditorFirmId	238
CY2023	dei	Auditor Name AuditorName	PricewaterhouseCoopers LLP
CY2023	dei	Auditor Location AuditorLocation	Boston, Massachusetts
CY2021	us-gaap	Revenue From Contract With Customer Excluding Assessed Tax RevenueFromContractWithCustomerExcludingAssessedTax	2412400000	usd
CY2022	us-gaap	Revenue From Contract With Customer Excluding Assessed Tax RevenueFromContractWithCustomerExcludingAssessedTax	2329600000	usd
CY2023	us-gaap	Revenue From Contract With Customer Excluding Assessed Tax RevenueFromContractWithCustomerExcludingAssessedTax	2057800000	usd
CY2021	us-gaap	Labor And Related Expense LaborAndRelatedExpense	1047100000	usd
CY2022	us-gaap	Labor And Related Expense LaborAndRelatedExpense	1071500000	usd
CY2023	us-gaap	Labor And Related Expense LaborAndRelatedExpense	907500000	usd
CY2021	us-gaap	Selling General And Administrative Expense SellingGeneralAndAdministrativeExpense	347100000	usd
CY2022	us-gaap	Selling General And Administrative Expense SellingGeneralAndAdministrativeExpense	385500000	usd
CY2023	us-gaap	Selling General And Administrative Expense SellingGeneralAndAdministrativeExpense	358200000	usd
CY2021	amg	Amortization And Impairments Of Intangible Assets AmortizationAndImpairmentsOfIntangibleAssets	35700000	usd
CY2022	amg	Amortization And Impairments Of Intangible Assets AmortizationAndImpairmentsOfIntangibleAssets	51600000	usd
CY2023	amg	Amortization And Impairments Of Intangible Assets AmortizationAndImpairmentsOfIntangibleAssets	48300000	usd
CY2021	us-gaap	Interest Expense InterestExpense	111400000	usd
CY2022	us-gaap	Interest Expense InterestExpense	114400000	usd
CY2023	us-gaap	Interest Expense InterestExpense	123800000	usd
CY2023	amg	Depreciation And Other Amortization DepreciationAndOtherAmortization	13000000.0	usd
CY2021	us-gaap	Other Cost And Expense Operating OtherCostAndExpenseOperating	73500000	usd
CY2022	us-gaap	Other Cost And Expense Operating OtherCostAndExpenseOperating	34700000	usd
CY2023	us-gaap	Other Cost And Expense Operating OtherCostAndExpenseOperating	45800000	usd
CY2021	us-gaap	Equity Method Investment Realized Gain Loss On Disposal EquityMethodInvestmentRealizedGainLossOnDisposal	0	usd
CY2022	us-gaap	Equity Method Investment Realized Gain Loss On Disposal EquityMethodInvestmentRealizedGainLossOnDisposal	641900000	usd
CY2023	us-gaap	Equity Method Investment Realized Gain Loss On Disposal EquityMethodInvestmentRealizedGainLossOnDisposal	133100000	usd
CY2021	us-gaap	Profit Loss ProfitLoss	890100000	usd
CY2022	us-gaap	Profit Loss ProfitLoss	1388100000	usd
CY2021	us-gaap	Net Income Loss Attributable To Noncontrolling Interest NetIncomeLossAttributableToNoncontrollingInterest	324400000	usd
CY2022	us-gaap	Net Income Loss Attributable To Noncontrolling Interest NetIncomeLossAttributableToNoncontrollingInterest	242200000	usd
CY2023	us-gaap	Net Income Loss Attributable To Noncontrolling Interest NetIncomeLossAttributableToNoncontrollingInterest	233200000	usd
CY2021	us-gaap	Net Income Loss NetIncomeLoss	565700000	usd
CY2021	us-gaap	Weighted Average Number Of Shares Outstanding Basic WeightedAverageNumberOfSharesOutstandingBasic	41500000	shares
CY2022	us-gaap	Weighted Average Number Of Shares Outstanding Basic WeightedAverageNumberOfSharesOutstandingBasic	38500000	shares
CY2021	us-gaap	Weighted Average Number Of Diluted Shares Outstanding WeightedAverageNumberOfDilutedSharesOutstanding	44800000	shares
CY2022	us-gaap	Weighted Average Number Of Diluted Shares Outstanding WeightedAverageNumberOfDilutedSharesOutstanding	49000000.0	shares
CY2023	us-gaap	Weighted Average Number Of Diluted Shares Outstanding WeightedAverageNumberOfDilutedSharesOutstanding	42200000	shares
CY2021	us-gaap	Earnings Per Share Basic EarningsPerShareBasic	13.65
CY2022	us-gaap	Earnings Per Share Basic EarningsPerShareBasic	29.77
CY2023	us-gaap	Earnings Per Share Basic EarningsPerShareBasic	19.18
CY2021	us-gaap	Earnings Per Share Diluted EarningsPerShareDiluted	13.05
CY2022	us-gaap	Earnings Per Share Diluted EarningsPerShareDiluted	25.35
CY2023	us-gaap	Earnings Per Share Diluted EarningsPerShareDiluted	17.42
CY2021	us-gaap	Profit Loss ProfitLoss	890100000	usd
CY2022	us-gaap	Profit Loss ProfitLoss	1388100000	usd
CY2023	us-gaap	Profit Loss ProfitLoss	906100000	usd
CY2021	us-gaap	Other Comprehensive Income Loss Foreign Currency Transaction And Translation Adjustment Net Of Tax OtherComprehensiveIncomeLossForeignCurrencyTransactionAndTranslationAdjustmentNetOfTax	6800000	usd
CY2022	us-gaap	Other Comprehensive Income Loss Foreign Currency Transaction And Translation Adjustment Net Of Tax OtherComprehensiveIncomeLossForeignCurrencyTransactionAndTranslationAdjustmentNetOfTax	-141300000	usd
CY2023	us-gaap	Other Comprehensive Income Loss Foreign Currency Transaction And Translation Adjustment Net Of Tax OtherComprehensiveIncomeLossForeignCurrencyTransactionAndTranslationAdjustmentNetOfTax	41100000	usd
CY2021	us-gaap	Other Comprehensive Income Loss Cash Flow Hedge Gain Loss After Reclassification And Tax OtherComprehensiveIncomeLossCashFlowHedgeGainLossAfterReclassificationAndTax	400000	usd
CY2022	us-gaap	Other Comprehensive Income Loss Cash Flow Hedge Gain Loss After Reclassification And Tax OtherComprehensiveIncomeLossCashFlowHedgeGainLossAfterReclassificationAndTax	-500000	usd
CY2023	us-gaap	Other Comprehensive Income Loss Cash Flow Hedge Gain Loss After Reclassification And Tax OtherComprehensiveIncomeLossCashFlowHedgeGainLossAfterReclassificationAndTax	300000	usd
CY2021	us-gaap	Other Comprehensive Income Loss Available For Sale Securities Adjustment Net Of Tax OtherComprehensiveIncomeLossAvailableForSaleSecuritiesAdjustmentNetOfTax	0	usd
CY2022	us-gaap	Other Comprehensive Income Loss Available For Sale Securities Adjustment Net Of Tax OtherComprehensiveIncomeLossAvailableForSaleSecuritiesAdjustmentNetOfTax	-1000000.0	usd
CY2023	us-gaap	Other Comprehensive Income Loss Available For Sale Securities Adjustment Net Of Tax OtherComprehensiveIncomeLossAvailableForSaleSecuritiesAdjustmentNetOfTax	500000	usd
CY2021	us-gaap	Other Comprehensive Income Loss Net Of Tax OtherComprehensiveIncomeLossNetOfTax	7200000	usd
CY2022	us-gaap	Other Comprehensive Income Loss Net Of Tax OtherComprehensiveIncomeLossNetOfTax	-142800000	usd
CY2023	us-gaap	Other Comprehensive Income Loss Net Of Tax OtherComprehensiveIncomeLossNetOfTax	41900000	usd
CY2021	us-gaap	Comprehensive Income Net Of Tax Including Portion Attributable To Noncontrolling Interest ComprehensiveIncomeNetOfTaxIncludingPortionAttributableToNoncontrollingInterest	897300000	usd
CY2022	us-gaap	Comprehensive Income Net Of Tax Including Portion Attributable To Noncontrolling Interest ComprehensiveIncomeNetOfTaxIncludingPortionAttributableToNoncontrollingInterest	1245300000	usd
CY2023	us-gaap	Comprehensive Income Net Of Tax Including Portion Attributable To Noncontrolling Interest ComprehensiveIncomeNetOfTaxIncludingPortionAttributableToNoncontrollingInterest	948000000.0	usd
CY2021	us-gaap	Comprehensive Income Net Of Tax Attributable To Noncontrolling Interest ComprehensiveIncomeNetOfTaxAttributableToNoncontrollingInterest	321200000	usd
CY2022	us-gaap	Comprehensive Income Net Of Tax Attributable To Noncontrolling Interest ComprehensiveIncomeNetOfTaxAttributableToNoncontrollingInterest	214900000	usd
CY2023	us-gaap	Comprehensive Income Net Of Tax Attributable To Noncontrolling Interest ComprehensiveIncomeNetOfTaxAttributableToNoncontrollingInterest	239300000	usd
CY2021	us-gaap	Comprehensive Income Net Of Tax ComprehensiveIncomeNetOfTax	576100000	usd
CY2022	us-gaap	Comprehensive Income Net Of Tax ComprehensiveIncomeNetOfTax	1030400000	usd
CY2023	us-gaap	Comprehensive Income Net Of Tax ComprehensiveIncomeNetOfTax	708700000	usd
CY2022Q4	us-gaap	Cash And Cash Equivalents At Carrying Value CashAndCashEquivalentsAtCarryingValue	429200000	usd
CY2023Q4	us-gaap	Cash And Cash Equivalents At Carrying Value CashAndCashEquivalentsAtCarryingValue	813600000	usd
CY2022Q4	us-gaap	Accounts Receivable Net AccountsReceivableNet	316000000.0	usd
CY2023Q4	us-gaap	Accounts Receivable Net AccountsReceivableNet	368400000	usd
CY2022Q4	us-gaap	Marketable Securities MarketableSecurities	716900000	usd
CY2023Q4	us-gaap	Marketable Securities MarketableSecurities	461000000.0	usd
CY2022Q4	us-gaap	Goodwill Goodwill	2648700000	usd
CY2023Q4	us-gaap	Goodwill Goodwill	2523600000	usd
CY2022Q4	us-gaap	Intangible Assets Net Excluding Goodwill IntangibleAssetsNetExcludingGoodwill	1876000000	usd
CY2023Q4	us-gaap	Intangible Assets Net Excluding Goodwill IntangibleAssetsNetExcludingGoodwill	1812400000	usd
CY2022Q4	us-gaap	Investments In Affiliates Subsidiaries Associates And Joint Ventures InvestmentsInAffiliatesSubsidiariesAssociatesAndJointVentures	2139500000	usd
CY2023Q4	us-gaap	Investments In Affiliates Subsidiaries Associates And Joint Ventures InvestmentsInAffiliatesSubsidiariesAssociatesAndJointVentures	2288500000	usd
CY2022Q4	us-gaap	Property Plant And Equipment Net PropertyPlantAndEquipmentNet	68500000	usd
CY2023Q4	us-gaap	Property Plant And Equipment Net PropertyPlantAndEquipmentNet	67300000	usd
CY2022Q4	us-gaap	Other Investments OtherInvestments	421600000	usd
CY2023Q4	us-gaap	Other Investments OtherInvestments	480900000	usd
CY2022Q4	us-gaap	Other Assets OtherAssets	264600000	usd
CY2023Q4	us-gaap	Other Assets OtherAssets	243900000	usd
CY2022Q4	us-gaap	Assets Assets	8881000000	usd
CY2023Q4	us-gaap	Assets Assets	9059600000	usd
CY2022Q4	us-gaap	Accounts Payable And Accrued Liabilities Current And Noncurrent AccountsPayableAndAccruedLiabilitiesCurrentAndNoncurrent	778300000	usd
CY2023Q4	us-gaap	Accounts Payable And Accrued Liabilities Current And Noncurrent AccountsPayableAndAccruedLiabilitiesCurrentAndNoncurrent	628500000	usd
CY2022Q4	us-gaap	Long Term Debt LongTermDebt	2535300000	usd
CY2023Q4	us-gaap	Long Term Debt LongTermDebt	2537500000	usd
CY2022Q4	us-gaap	Deferred Income Tax Liabilities Net DeferredIncomeTaxLiabilitiesNet	464700000	usd
CY2023Q4	us-gaap	Deferred Income Tax Liabilities Net DeferredIncomeTaxLiabilitiesNet	463800000	usd
CY2022Q4	us-gaap	Other Liabilities OtherLiabilities	461700000	usd
CY2023Q4	us-gaap	Other Liabilities OtherLiabilities	466300000	usd
CY2022Q4	us-gaap	Liabilities Liabilities	4240000000	usd
CY2023Q4	us-gaap	Liabilities Liabilities	4096100000	usd
CY2022Q4	us-gaap	Commitments And Contingencies CommitmentsAndContingencies		usd
CY2023Q4	us-gaap	Commitments And Contingencies CommitmentsAndContingencies		usd
CY2022Q4	us-gaap	Redeemable Noncontrolling Interest Equity Carrying Amount RedeemableNoncontrollingInterestEquityCarryingAmount	465400000	usd
CY2023Q4	us-gaap	Redeemable Noncontrolling Interest Equity Carrying Amount RedeemableNoncontrollingInterestEquityCarryingAmount	393400000	usd
CY2022Q4	us-gaap	Common Stock Par Or Stated Value Per Share CommonStockParOrStatedValuePerShare	0.01
CY2023Q4	us-gaap	Common Stock Par Or Stated Value Per Share CommonStockParOrStatedValuePerShare	0.01
CY2023Q4	us-gaap	Common Stock Shares Authorized CommonStockSharesAuthorized	153000000.0	shares
CY2022Q4	us-gaap	Common Stock Shares Authorized CommonStockSharesAuthorized	153000000.0	shares
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CY2023Q4	us-gaap	Common Stock Shares Issued CommonStockSharesIssued	58500000	shares
CY2022Q4	us-gaap	Common Stock Value CommonStockValue	600000	usd
CY2023Q4	us-gaap	Common Stock Value CommonStockValue	600000	usd
CY2022Q4	us-gaap	Additional Paid In Capital Common Stock AdditionalPaidInCapitalCommonStock	695500000	usd
CY2023Q4	us-gaap	Additional Paid In Capital Common Stock AdditionalPaidInCapitalCommonStock	741400000	usd
CY2022Q4	amg	Accumulated Other Comprehensive Income Loss Attributable To Parent Net Of Tax AccumulatedOtherComprehensiveIncomeLossAttributableToParentNetOfTax	-203400000	usd
CY2023Q4	amg	Accumulated Other Comprehensive Income Loss Attributable To Parent Net Of Tax AccumulatedOtherComprehensiveIncomeLossAttributableToParentNetOfTax	-167600000	usd
CY2022Q4	us-gaap	Retained Earnings Accumulated Deficit RetainedEarningsAccumulatedDeficit	5718200000	usd
CY2023Q4	us-gaap	Retained Earnings Accumulated Deficit RetainedEarningsAccumulatedDeficit	6389600000	usd
CY2022Q4	us-gaap	Stockholders Equity Before Treasury Stock StockholdersEquityBeforeTreasuryStock	6210900000	usd
CY2023Q4	us-gaap	Stockholders Equity Before Treasury Stock StockholdersEquityBeforeTreasuryStock	6964000000	usd
CY2022Q4	us-gaap	Treasury Stock Common Shares TreasuryStockCommonShares	22700000	shares
CY2023Q4	us-gaap	Treasury Stock Common Shares TreasuryStockCommonShares	25300000	shares
CY2022Q4	us-gaap	Treasury Stock Common Value TreasuryStockCommonValue	2980600000	usd
CY2023Q4	us-gaap	Treasury Stock Common Value TreasuryStockCommonValue	3376100000	usd
CY2022Q4	us-gaap	Stockholders Equity StockholdersEquity	3230300000	usd
CY2023Q4	us-gaap	Stockholders Equity StockholdersEquity	3587900000	usd
CY2022Q4	us-gaap	Other Minority Interests OtherMinorityInterests	945300000	usd
CY2023Q4	us-gaap	Other Minority Interests OtherMinorityInterests	982200000	usd
CY2022Q4	us-gaap	Stockholders Equity Including Portion Attributable To Noncontrolling Interest StockholdersEquityIncludingPortionAttributableToNoncontrollingInterest	4175600000	usd
CY2023Q4	us-gaap	Stockholders Equity Including Portion Attributable To Noncontrolling Interest StockholdersEquityIncludingPortionAttributableToNoncontrollingInterest	4570100000	usd
CY2022Q4	us-gaap	Liabilities And Stockholders Equity LiabilitiesAndStockholdersEquity	8881000000	usd
CY2023Q4	us-gaap	Liabilities And Stockholders Equity LiabilitiesAndStockholdersEquity	9059600000	usd
CY2020Q4	us-gaap	Stockholders Equity Including Portion Attributable To Noncontrolling Interest StockholdersEquityIncludingPortionAttributableToNoncontrollingInterest	3317300000	usd
CY2021	us-gaap	Profit Loss ProfitLoss	890100000	usd
CY2021	us-gaap	Other Comprehensive Income Loss Net Of Tax OtherComprehensiveIncomeLossNetOfTax	7200000	usd
CY2021	us-gaap	Adjustments To Additional Paid In Capital Sharebased Compensation Requisite Service Period Recognition Value AdjustmentsToAdditionalPaidInCapitalSharebasedCompensationRequisiteServicePeriodRecognitionValue	63400000	usd
CY2021	us-gaap	Stock Issued During Period Value Share Based Compensation StockIssuedDuringPeriodValueShareBasedCompensation	-16700000	usd
CY2021	us-gaap	Adjustments To Additional Paid In Capital Equity Component Of Convertible Debt AdjustmentsToAdditionalPaidInCapitalEquityComponentOfConvertibleDebt	7100000	usd
CY2021	us-gaap	Treasury Stock Value Acquired Cost Method TreasuryStockValueAcquiredCostMethod	509900000	usd
CY2021	us-gaap	Common Stock Dividends Per Share Cash Paid CommonStockDividendsPerShareCashPaid	0.04
CY2021	us-gaap	Dividends Common Stock Cash DividendsCommonStockCash	1700000	usd
CY2021	amg	Noncontrolling Interest Increase From Investments In Affiliates NoncontrollingInterestIncreaseFromInvestmentsInAffiliates	247000000.0	usd
CY2021	amg	Affiliate Equity Compensation Expense Including Adjustments And Portion Attributable To Noncontrolling Interest AffiliateEquityCompensationExpenseIncludingAdjustmentsAndPortionAttributableToNoncontrollingInterest	62900000	usd
CY2021	amg	Noncontrolling Interest Increase Decrease From Subsidiary Equity Issuance NoncontrollingInterestIncreaseDecreaseFromSubsidiaryEquityIssuance	103900000	usd
CY2021	amg	Noncontrolling Interest Increase Decreasefrom Purchaseof Interests NoncontrollingInterestIncreaseDecreasefromPurchaseofInterests	2800000	usd
CY2021	amg	Redeemable Noncontrolling Interest Equity Change In Redemption Value RedeemableNoncontrollingInterestEquityChangeInRedemptionValue	-121600000	usd
CY2021	amg	Noncontrolling Interest Transfers To From Noncontrolling Interest Holders NoncontrollingInterestTransfersToFromNoncontrollingInterestHolders	3900000	usd
CY2021	amg	Noncontrolling Interest Increase Decrease From Contributions From Affiliate And Other NoncontrollingInterestIncreaseDecreaseFromContributionsFromAffiliateAndOther	11200000	usd
CY2021	us-gaap	Minority Interest Decrease From Distributions To Noncontrolling Interest Holders MinorityInterestDecreaseFromDistributionsToNoncontrollingInterestHolders	334300000	usd
CY2021Q4	us-gaap	Stockholders Equity Including Portion Attributable To Noncontrolling Interest StockholdersEquityIncludingPortionAttributableToNoncontrollingInterest	3710600000	usd
CY2022	us-gaap	Profit Loss ProfitLoss	1388100000	usd
CY2022	us-gaap	Other Comprehensive Income Loss Net Of Tax OtherComprehensiveIncomeLossNetOfTax	-142800000	usd
CY2022	us-gaap	Adjustments To Additional Paid In Capital Sharebased Compensation Requisite Service Period Recognition Value AdjustmentsToAdditionalPaidInCapitalSharebasedCompensationRequisiteServicePeriodRecognitionValue	62400000	usd
CY2022	us-gaap	Stock Issued During Period Value Share Based Compensation StockIssuedDuringPeriodValueShareBasedCompensation	-17100000	usd
CY2022	us-gaap	Treasury Stock Value Acquired Cost Method TreasuryStockValueAcquiredCostMethod	699700000	usd
CY2022	us-gaap	Common Stock Dividends Per Share Cash Paid CommonStockDividendsPerShareCashPaid	0.04
CY2022	us-gaap	Dividends Common Stock Cash DividendsCommonStockCash	1700000	usd
CY2022	amg	Affiliate Equity Compensation Expense Including Adjustments And Portion Attributable To Noncontrolling Interest AffiliateEquityCompensationExpenseIncludingAdjustmentsAndPortionAttributableToNoncontrollingInterest	55900000	usd
CY2022	amg	Noncontrolling Interest Increase Decrease From Subsidiary Equity Issuance NoncontrollingInterestIncreaseDecreaseFromSubsidiaryEquityIssuance	19200000	usd
CY2022	amg	Noncontrolling Interest Increase Decreasefrom Purchaseof Interests NoncontrollingInterestIncreaseDecreasefromPurchaseofInterests	-12000000.0	usd
CY2022	amg	Redeemable Noncontrolling Interest Equity Change In Redemption Value RedeemableNoncontrollingInterestEquityChangeInRedemptionValue	145800000	usd
CY2022	amg	Noncontrolling Interest Transfers To From Noncontrolling Interest Holders NoncontrollingInterestTransfersToFromNoncontrollingInterestHolders	1800000	usd
CY2022	amg	Noncontrolling Interest Increase Decrease From Contributions From Affiliate And Other NoncontrollingInterestIncreaseDecreaseFromContributionsFromAffiliateAndOther	86700000	usd
CY2022	us-gaap	Minority Interest Decrease From Distributions To Noncontrolling Interest Holders MinorityInterestDecreaseFromDistributionsToNoncontrollingInterestHolders	341900000	usd
CY2022Q4	us-gaap	Stockholders Equity Including Portion Attributable To Noncontrolling Interest StockholdersEquityIncludingPortionAttributableToNoncontrollingInterest	4175600000	usd
CY2023	us-gaap	Profit Loss ProfitLoss	906100000	usd
CY2023	us-gaap	Other Comprehensive Income Loss Net Of Tax OtherComprehensiveIncomeLossNetOfTax	41900000	usd
CY2023	us-gaap	Adjustments To Additional Paid In Capital Sharebased Compensation Requisite Service Period Recognition Value AdjustmentsToAdditionalPaidInCapitalSharebasedCompensationRequisiteServicePeriodRecognitionValue	59400000	usd
CY2023	us-gaap	Stock Issued During Period Value Share Based Compensation StockIssuedDuringPeriodValueShareBasedCompensation	-31300000	usd
CY2023	us-gaap	Treasury Stock Value Acquired Cost Method TreasuryStockValueAcquiredCostMethod	352300000	usd
CY2023	us-gaap	Common Stock Dividends Per Share Cash Paid CommonStockDividendsPerShareCashPaid	0.04
CY2023	us-gaap	Dividends Common Stock Cash DividendsCommonStockCash	1500000	usd
CY2023	amg	Affiliate Equity Compensation Expense Including Adjustments And Portion Attributable To Noncontrolling Interest AffiliateEquityCompensationExpenseIncludingAdjustmentsAndPortionAttributableToNoncontrollingInterest	52500000	usd
CY2023	amg	Noncontrolling Interest Increase Decrease From Subsidiary Equity Issuance NoncontrollingInterestIncreaseDecreaseFromSubsidiaryEquityIssuance	16400000	usd
CY2023	amg	Noncontrolling Interest Increase Decreasefrom Purchaseof Interests NoncontrollingInterestIncreaseDecreasefromPurchaseofInterests	8100000	usd
CY2023	amg	Redeemable Noncontrolling Interest Equity Change In Redemption Value RedeemableNoncontrollingInterestEquityChangeInRedemptionValue	-55500000	usd
CY2023	amg	Noncontrolling Interest Transfers To From Noncontrolling Interest Holders NoncontrollingInterestTransfersToFromNoncontrollingInterestHolders	-8900000	usd
CY2023	amg	Noncontrolling Interest Increase Decrease From Contributions From Affiliate And Other NoncontrollingInterestIncreaseDecreaseFromContributionsFromAffiliateAndOther	13500000	usd
CY2023	us-gaap	Minority Interest Decrease From Distributions To Noncontrolling Interest Holders MinorityInterestDecreaseFromDistributionsToNoncontrollingInterestHolders	271300000	usd
CY2023	us-gaap	Noncontrolling Interest Decrease From Deconsolidation NoncontrollingInterestDecreaseFromDeconsolidation	400000	usd
CY2023Q4	us-gaap	Stockholders Equity Including Portion Attributable To Noncontrolling Interest StockholdersEquityIncludingPortionAttributableToNoncontrollingInterest	4570100000	usd
CY2021	us-gaap	Profit Loss ProfitLoss	890100000	usd
CY2022	us-gaap	Profit Loss ProfitLoss	1388100000	usd
CY2023	us-gaap	Profit Loss ProfitLoss	906100000	usd
CY2021	amg	Amortization And Impairments Of Intangible Assets AmortizationAndImpairmentsOfIntangibleAssets	35700000	usd
CY2022	amg	Amortization And Impairments Of Intangible Assets AmortizationAndImpairmentsOfIntangibleAssets	51600000	usd
CY2023	amg	Amortization And Impairments Of Intangible Assets AmortizationAndImpairmentsOfIntangibleAssets	48300000	usd
CY2021	amg	Depreciation And Other Amortization DepreciationAndOtherAmortization	16600000	usd
CY2022	amg	Depreciation And Other Amortization DepreciationAndOtherAmortization	15800000	usd
CY2023	amg	Depreciation And Other Amortization DepreciationAndOtherAmortization	13000000.0	usd
CY2021	us-gaap	Deferred Income Tax Expense Benefit DeferredIncomeTaxExpenseBenefit	91200000	usd
CY2022	us-gaap	Deferred Income Tax Expense Benefit DeferredIncomeTaxExpenseBenefit	32000000.0	usd
CY2023	us-gaap	Deferred Income Tax Expense Benefit DeferredIncomeTaxExpenseBenefit	31400000	usd
CY2021	us-gaap	Income Loss From Equity Method Investments IncomeLossFromEquityMethodInvestments	242500000	usd
CY2022	us-gaap	Income Loss From Equity Method Investments IncomeLossFromEquityMethodInvestments	338100000	usd
CY2023	us-gaap	Income Loss From Equity Method Investments IncomeLossFromEquityMethodInvestments	280000000.0	usd
CY2021	us-gaap	Equity Method Investment Dividends Or Distributions EquityMethodInvestmentDividendsOrDistributions	337500000	usd
CY2022	us-gaap	Equity Method Investment Dividends Or Distributions EquityMethodInvestmentDividendsOrDistributions	393500000	usd
CY2023	us-gaap	Equity Method Investment Dividends Or Distributions EquityMethodInvestmentDividendsOrDistributions	490800000	usd
CY2021	us-gaap	Equity Method Investment Realized Gain Loss On Disposal EquityMethodInvestmentRealizedGainLossOnDisposal	0	usd
CY2022	us-gaap	Equity Method Investment Realized Gain Loss On Disposal EquityMethodInvestmentRealizedGainLossOnDisposal	641900000	usd
CY2023	us-gaap	Equity Method Investment Realized Gain Loss On Disposal EquityMethodInvestmentRealizedGainLossOnDisposal	133100000	usd
CY2021	us-gaap	Share Based Compensation ShareBasedCompensation	126700000	usd
CY2022	us-gaap	Share Based Compensation ShareBasedCompensation	113800000	usd
CY2023	us-gaap	Share Based Compensation ShareBasedCompensation	112100000	usd
CY2021	amg	Realized And Unrealized Investment Gains Losses RealizedAndUnrealizedInvestmentGainsLosses	108700000	usd
CY2022	amg	Realized And Unrealized Investment Gains Losses RealizedAndUnrealizedInvestmentGainsLosses	103500000	usd
CY2023	amg	Realized And Unrealized Investment Gains Losses RealizedAndUnrealizedInvestmentGainsLosses	84200000	usd
CY2021	us-gaap	Other Noncash Income Expense OtherNoncashIncomeExpense	-44200000	usd
CY2022	us-gaap	Other Noncash Income Expense OtherNoncashIncomeExpense	-17800000	usd
CY2023	us-gaap	Other Noncash Income Expense OtherNoncashIncomeExpense	10800000	usd
CY2021	amg	Purchasesof Securitiesby Affiliate Sponsored Consolidated Products PurchasesofSecuritiesbyAffiliateSponsoredConsolidatedProducts	109600000	usd
CY2022	amg	Purchasesof Securitiesby Affiliate Sponsored Consolidated Products PurchasesofSecuritiesbyAffiliateSponsoredConsolidatedProducts	46700000	usd
CY2023	amg	Purchasesof Securitiesby Affiliate Sponsored Consolidated Products PurchasesofSecuritiesbyAffiliateSponsoredConsolidatedProducts	45000000.0	usd
CY2021	amg	Saleof Securitiesby Affiliate Sponsored Consolidated Products SaleofSecuritiesbyAffiliateSponsoredConsolidatedProducts	58000000.0	usd
CY2022	amg	Saleof Securitiesby Affiliate Sponsored Consolidated Products SaleofSecuritiesbyAffiliateSponsoredConsolidatedProducts	33800000	usd
CY2023	amg	Saleof Securitiesby Affiliate Sponsored Consolidated Products SaleofSecuritiesbyAffiliateSponsoredConsolidatedProducts	54300000	usd
CY2021	us-gaap	Increase Decrease In Receivables IncreaseDecreaseInReceivables	-31700000	usd
CY2022	us-gaap	Increase Decrease In Receivables IncreaseDecreaseInReceivables	-87000000.0	usd
CY2023	us-gaap	Increase Decrease In Receivables IncreaseDecreaseInReceivables	48400000	usd
CY2021	us-gaap	Increase Decrease In Other Operating Assets IncreaseDecreaseInOtherOperatingAssets	-23800000	usd
CY2022	us-gaap	Increase Decrease In Other Operating Assets IncreaseDecreaseInOtherOperatingAssets	-41600000	usd
CY2023	us-gaap	Increase Decrease In Other Operating Assets IncreaseDecreaseInOtherOperatingAssets	-9200000	usd
CY2021	us-gaap	Increase Decrease In Operating Liabilities IncreaseDecreaseInOperatingLiabilities	64500000	usd
CY2022	us-gaap	Increase Decrease In Operating Liabilities IncreaseDecreaseInOperatingLiabilities	9900000	usd
CY2023	us-gaap	Increase Decrease In Operating Liabilities IncreaseDecreaseInOperatingLiabilities	-189400000	usd
CY2021	us-gaap	Net Cash Provided By Used In Operating Activities NetCashProvidedByUsedInOperatingActivities	1259200000	usd
CY2022	us-gaap	Net Cash Provided By Used In Operating Activities NetCashProvidedByUsedInOperatingActivities	1054700000	usd
CY2023	us-gaap	Net Cash Provided By Used In Operating Activities NetCashProvidedByUsedInOperatingActivities	874300000	usd
CY2021	us-gaap	Payments To Acquire Interest In Subsidiaries And Affiliates PaymentsToAcquireInterestInSubsidiariesAndAffiliates	562600000	usd
CY2022	us-gaap	Payments To Acquire Interest In Subsidiaries And Affiliates PaymentsToAcquireInterestInSubsidiariesAndAffiliates	291100000	usd
CY2023	us-gaap	Payments To Acquire Interest In Subsidiaries And Affiliates PaymentsToAcquireInterestInSubsidiariesAndAffiliates	294700000	usd
CY2021	us-gaap	Proceeds From Divestiture Of Interest In Subsidiaries And Affiliates ProceedsFromDivestitureOfInterestInSubsidiariesAndAffiliates	0	usd
CY2022	us-gaap	Proceeds From Divestiture Of Interest In Subsidiaries And Affiliates ProceedsFromDivestitureOfInterestInSubsidiariesAndAffiliates	223600000	usd
CY2023	us-gaap	Proceeds From Divestiture Of Interest In Subsidiaries And Affiliates ProceedsFromDivestitureOfInterestInSubsidiariesAndAffiliates	294000000.0	usd
CY2021	amg	Proceeds From Equity Method Investment Return Of Capital ProceedsFromEquityMethodInvestmentReturnOfCapital	4400000	usd
CY2022	amg	Proceeds From Equity Method Investment Return Of Capital ProceedsFromEquityMethodInvestmentReturnOfCapital	800000	usd
CY2023	amg	Proceeds From Equity Method Investment Return Of Capital ProceedsFromEquityMethodInvestmentReturnOfCapital	200000	usd
CY2021	us-gaap	Payments To Acquire Property Plant And Equipment PaymentsToAcquirePropertyPlantAndEquipment	8400000	usd
CY2022	us-gaap	Income Taxes Paid Net IncomeTaxesPaidNet	120200000	usd
CY2023	us-gaap	Income Taxes Paid Net IncomeTaxesPaidNet	314500000	usd
CY2021	us-gaap	Interest Paid Net InterestPaidNet	103000000.0	usd
CY2022	us-gaap	Payments To Acquire Property Plant And Equipment PaymentsToAcquirePropertyPlantAndEquipment	11400000	usd
CY2023	us-gaap	Payments To Acquire Property Plant And Equipment PaymentsToAcquirePropertyPlantAndEquipment	12400000	usd
CY2021	us-gaap	Payments To Acquire Marketable Securities PaymentsToAcquireMarketableSecurities	73500000	usd
CY2022	us-gaap	Payments To Acquire Marketable Securities PaymentsToAcquireMarketableSecurities	312000000.0	usd
CY2023	us-gaap	Payments To Acquire Marketable Securities PaymentsToAcquireMarketableSecurities	731100000	usd
CY2021	us-gaap	Proceeds From Sale Maturity And Collections Of Investments ProceedsFromSaleMaturityAndCollectionsOfInvestments	56400000	usd
CY2022	us-gaap	Proceeds From Sale Maturity And Collections Of Investments ProceedsFromSaleMaturityAndCollectionsOfInvestments	280200000	usd
CY2023	us-gaap	Proceeds From Sale Maturity And Collections Of Investments ProceedsFromSaleMaturityAndCollectionsOfInvestments	1008500000	usd
CY2021	us-gaap	Net Cash Provided By Used In Investing Activities NetCashProvidedByUsedInInvestingActivities	-583700000	usd
CY2022	us-gaap	Net Cash Provided By Used In Investing Activities NetCashProvidedByUsedInInvestingActivities	-109900000	usd
CY2023	us-gaap	Net Cash Provided By Used In Investing Activities NetCashProvidedByUsedInInvestingActivities	264500000	usd
CY2021	us-gaap	Proceeds From Issuance Of Long Term Debt ProceedsFromIssuanceOfLongTermDebt	200000000.0	usd
CY2022	us-gaap	Proceeds From Issuance Of Long Term Debt ProceedsFromIssuanceOfLongTermDebt	0	usd
CY2023	us-gaap	Proceeds From Issuance Of Long Term Debt ProceedsFromIssuanceOfLongTermDebt	25000000.0	usd
CY2021	us-gaap	Repayments Of Long Term Debt RepaymentsOfLongTermDebt	33000000.0	usd
CY2022	us-gaap	Repayments Of Long Term Debt RepaymentsOfLongTermDebt	60800000	usd
CY2023	us-gaap	Repayments Of Long Term Debt RepaymentsOfLongTermDebt	25000000.0	usd
CY2021	us-gaap	Payments For Repurchase Of Common Stock PaymentsForRepurchaseOfCommonStock	595300000	usd
CY2022	us-gaap	Payments For Repurchase Of Common Stock PaymentsForRepurchaseOfCommonStock	713800000	usd
CY2023	us-gaap	Payments For Repurchase Of Common Stock PaymentsForRepurchaseOfCommonStock	341900000	usd
CY2021	us-gaap	Payments Of Dividends Common Stock PaymentsOfDividendsCommonStock	1700000	usd
CY2022	us-gaap	Payments Of Dividends Common Stock PaymentsOfDividendsCommonStock	1600000	usd
CY2023	us-gaap	Payments Of Dividends Common Stock PaymentsOfDividendsCommonStock	1500000	usd
CY2021	us-gaap	Payments Of Dividends Minority Interest PaymentsOfDividendsMinorityInterest	334300000	usd
CY2022	us-gaap	Payments Of Dividends Minority Interest PaymentsOfDividendsMinorityInterest	341900000	usd
CY2023	us-gaap	Payments Of Dividends Minority Interest PaymentsOfDividendsMinorityInterest	271300000	usd
CY2021	amg	Proceeds From Payments For Affiliate Equity Issuances And Repurchases ProceedsFromPaymentsForAffiliateEquityIssuancesAndRepurchases	150500000	usd
CY2022	amg	Proceeds From Payments For Affiliate Equity Issuances And Repurchases ProceedsFromPaymentsForAffiliateEquityIssuancesAndRepurchases	61500000	usd
CY2023	amg	Proceeds From Payments For Affiliate Equity Issuances And Repurchases ProceedsFromPaymentsForAffiliateEquityIssuancesAndRepurchases	67400000	usd
CY2021	amg	Proceeds From Affiliate Equity Issuances ProceedsFromAffiliateEquityIssuances	117700000	usd
CY2022	amg	Proceeds From Affiliate Equity Issuances ProceedsFromAffiliateEquityIssuances	15200000	usd
CY2023	amg	Proceeds From Affiliate Equity Issuances ProceedsFromAffiliateEquityIssuances	13400000	usd
CY2021	amg	Subscriptions To Consolidated Affiliate Sponsored Investment Products Net Of Redemptions SubscriptionsToConsolidatedAffiliateSponsoredInvestmentProductsNetOfRedemptions	40900000	usd
CY2022	amg	Subscriptions To Consolidated Affiliate Sponsored Investment Products Net Of Redemptions SubscriptionsToConsolidatedAffiliateSponsoredInvestmentProductsNetOfRedemptions	13000000.0	usd
CY2023	amg	Subscriptions To Consolidated Affiliate Sponsored Investment Products Net Of Redemptions SubscriptionsToConsolidatedAffiliateSponsoredInvestmentProductsNetOfRedemptions	-12600000	usd
CY2021	amg	Settlement Of Deferred Payment Obligations SettlementOfDeferredPaymentObligations	21700000	usd
CY2022	amg	Settlement Of Deferred Payment Obligations SettlementOfDeferredPaymentObligations	201000000.0	usd
CY2023	amg	Settlement Of Deferred Payment Obligations SettlementOfDeferredPaymentObligations	21700000	usd
CY2021	us-gaap	Proceeds From Payments For Other Financing Activities ProceedsFromPaymentsForOtherFinancingActivities	-20400000	usd
CY2022	us-gaap	Proceeds From Payments For Other Financing Activities ProceedsFromPaymentsForOtherFinancingActivities	-50500000	usd
CY2023	us-gaap	Proceeds From Payments For Other Financing Activities ProceedsFromPaymentsForOtherFinancingActivities	-55300000	usd
CY2021	us-gaap	Net Cash Provided By Used In Financing Activities NetCashProvidedByUsedInFinancingActivities	-798300000	usd
CY2022	us-gaap	Net Cash Provided By Used In Financing Activities NetCashProvidedByUsedInFinancingActivities	-1402900000	usd
CY2023	us-gaap	Net Cash Provided By Used In Financing Activities NetCashProvidedByUsedInFinancingActivities	-758300000	usd
CY2021	us-gaap	Effect Of Exchange Rate On Cash Cash Equivalents Restricted Cash And Restricted Cash Equivalents EffectOfExchangeRateOnCashCashEquivalentsRestrictedCashAndRestrictedCashEquivalents	-800000	usd
CY2022	us-gaap	Effect Of Exchange Rate On Cash Cash Equivalents Restricted Cash And Restricted Cash Equivalents EffectOfExchangeRateOnCashCashEquivalentsRestrictedCashAndRestrictedCashEquivalents	-22600000	usd
CY2023	us-gaap	Effect Of Exchange Rate On Cash Cash Equivalents Restricted Cash And Restricted Cash Equivalents EffectOfExchangeRateOnCashCashEquivalentsRestrictedCashAndRestrictedCashEquivalents	6900000	usd
CY2021	us-gaap	Cash Cash Equivalents Restricted Cash And Restricted Cash Equivalents Period Increase Decrease Including Exchange Rate Effect CashCashEquivalentsRestrictedCashAndRestrictedCashEquivalentsPeriodIncreaseDecreaseIncludingExchangeRateEffect	-123600000	usd
CY2022	us-gaap	Cash Cash Equivalents Restricted Cash And Restricted Cash Equivalents Period Increase Decrease Including Exchange Rate Effect CashCashEquivalentsRestrictedCashAndRestrictedCashEquivalentsPeriodIncreaseDecreaseIncludingExchangeRateEffect	-480700000	usd
CY2023	us-gaap	Cash Cash Equivalents Restricted Cash And Restricted Cash Equivalents Period Increase Decrease Including Exchange Rate Effect CashCashEquivalentsRestrictedCashAndRestrictedCashEquivalentsPeriodIncreaseDecreaseIncludingExchangeRateEffect	387400000	usd
CY2020Q4	us-gaap	Cash Cash Equivalents Restricted Cash And Restricted Cash Equivalents CashCashEquivalentsRestrictedCashAndRestrictedCashEquivalents	1039700000	usd
CY2021Q4	us-gaap	Cash Cash Equivalents Restricted Cash And Restricted Cash Equivalents CashCashEquivalentsRestrictedCashAndRestrictedCashEquivalents	908500000	usd
CY2022Q4	us-gaap	Cash Cash Equivalents Restricted Cash And Restricted Cash Equivalents CashCashEquivalentsRestrictedCashAndRestrictedCashEquivalents	429200000	usd
CY2021Q4	amg	Reduction To Cash Due To Deconsolidation Of Affiliates And Affiliate Sponsored Investment Products ReductionToCashDueToDeconsolidationOfAffiliatesAndAffiliateSponsoredInvestmentProducts	7600000	usd
CY2022Q4	amg	Reduction To Cash Due To Deconsolidation Of Affiliates And Affiliate Sponsored Investment Products ReductionToCashDueToDeconsolidationOfAffiliatesAndAffiliateSponsoredInvestmentProducts	-1400000	usd
CY2023Q4	amg	Reduction To Cash Due To Deconsolidation Of Affiliates And Affiliate Sponsored Investment Products ReductionToCashDueToDeconsolidationOfAffiliatesAndAffiliateSponsoredInvestmentProducts	3000000.0	usd
CY2021Q4	us-gaap	Cash Cash Equivalents Restricted Cash And Restricted Cash Equivalents CashCashEquivalentsRestrictedCashAndRestrictedCashEquivalents	908500000	usd
CY2022Q4	us-gaap	Cash Cash Equivalents Restricted Cash And Restricted Cash Equivalents CashCashEquivalentsRestrictedCashAndRestrictedCashEquivalents	429200000	usd
CY2023Q4	us-gaap	Cash Cash Equivalents Restricted Cash And Restricted Cash Equivalents CashCashEquivalentsRestrictedCashAndRestrictedCashEquivalents	813600000	usd
CY2021	us-gaap	Income Taxes Paid Net IncomeTaxesPaidNet	87100000	usd
CY2022	us-gaap	Interest Paid Net InterestPaidNet	109400000	usd
CY2023	us-gaap	Interest Paid Net InterestPaidNet	110400000	usd
CY2021	us-gaap	Operating Lease Payments OperatingLeasePayments	38800000	usd
CY2022	us-gaap	Operating Lease Payments OperatingLeasePayments	41800000	usd
CY2023	us-gaap	Operating Lease Payments OperatingLeasePayments	37700000	usd
CY2021	amg	Payables Recorded But Not Yet Paid Investments In Affiliates PayablesRecordedButNotYetPaidInvestmentsInAffiliates	287800000	usd
CY2022	amg	Payables Recorded But Not Yet Paid Investments In Affiliates PayablesRecordedButNotYetPaidInvestmentsInAffiliates	31200000	usd
CY2023	amg	Payables Recorded But Not Yet Paid Investments In Affiliates PayablesRecordedButNotYetPaidInvestmentsInAffiliates	57600000	usd
CY2021	us-gaap	Right Of Use Asset Obtained In Exchange For Operating Lease Liability RightOfUseAssetObtainedInExchangeForOperatingLeaseLiability	26300000	usd
CY2022	us-gaap	Right Of Use Asset Obtained In Exchange For Operating Lease Liability RightOfUseAssetObtainedInExchangeForOperatingLeaseLiability	69400000	usd
CY2023	us-gaap	Right Of Use Asset Obtained In Exchange For Operating Lease Liability RightOfUseAssetObtainedInExchangeForOperatingLeaseLiability	17500000	usd
CY2021	amg	Stock Issued Under Other Incentive Plans StockIssuedUnderOtherIncentivePlans	82600000	usd
CY2022	amg	Stock Issued Under Other Incentive Plans StockIssuedUnderOtherIncentivePlans	41200000	usd
CY2023	amg	Stock Issued Under Other Incentive Plans StockIssuedUnderOtherIncentivePlans	55000000.0	usd
CY2021	amg	Shares Receivedfor Tax Withholdingfor Share Based Compensation Value SharesReceivedforTaxWithholdingforShareBasedCompensationValue	19900000	usd
CY2022	amg	Shares Receivedfor Tax Withholdingfor Share Based Compensation Value SharesReceivedforTaxWithholdingforShareBasedCompensationValue	19400000	usd
CY2023	amg	Shares Receivedfor Tax Withholdingfor Share Based Compensation Value SharesReceivedforTaxWithholdingforShareBasedCompensationValue	31400000	usd
CY2023	amg	Shares Received For Settlement Of Accelerated Share Repurchase Agreement Value SharesReceivedForSettlementOfAcceleratedShareRepurchaseAgreementValue	0	usd
CY2022	amg	Shares Received For Settlement Of Accelerated Share Repurchase Agreement Value SharesReceivedForSettlementOfAcceleratedShareRepurchaseAgreementValue	0	usd
CY2021	amg	Shares Received For Settlement Of Accelerated Share Repurchase Agreement Value SharesReceivedForSettlementOfAcceleratedShareRepurchaseAgreementValue	14100000	usd
CY2021	amg	Payables Recorded But Not Yet Paid Share Repurchases PayablesRecordedButNotYetPaidShareRepurchases	16700000	usd
CY2022	amg	Payables Recorded But Not Yet Paid Share Repurchases PayablesRecordedButNotYetPaidShareRepurchases	0	usd
CY2023	amg	Payables Recorded But Not Yet Paid Share Repurchases PayablesRecordedButNotYetPaidShareRepurchases	12000000.0	usd
CY2021	amg	Payables Recorded For Affiliate Equity Purchases PayablesRecordedForAffiliateEquityPurchases	11000000.0	usd
CY2022	amg	Payables Recorded For Affiliate Equity Purchases PayablesRecordedForAffiliateEquityPurchases	27200000	usd
CY2023	amg	Payables Recorded For Affiliate Equity Purchases PayablesRecordedForAffiliateEquityPurchases	43000000.0	usd
CY2021	amg	Sale Of Equity Interests Equity Interests Issuable Proceeds SaleOfEquityInterestsEquityInterestsIssuableProceeds	0	usd
CY2022	amg	Sale Of Equity Interests Equity Interests Issuable Proceeds SaleOfEquityInterestsEquityInterestsIssuableProceeds	515200000	usd
CY2023	amg	Sale Of Equity Interests Equity Interests Issuable Proceeds SaleOfEquityInterestsEquityInterestsIssuableProceeds	0	usd
CY2021	amg	Sale Of Equity Interests Proceeds From Other Investments SaleOfEquityInterestsProceedsFromOtherInvestments	0	usd
CY2022	amg	Sale Of Equity Interests Proceeds From Other Investments SaleOfEquityInterestsProceedsFromOtherInvestments	51700000	usd
CY2023	amg	Sale Of Equity Interests Proceeds From Other Investments SaleOfEquityInterestsProceedsFromOtherInvestments	0	usd
CY2023	us-gaap	Number Of Operating Segments NumberOfOperatingSegments	1	segment
CY2023	us-gaap	Use Of Estimates UseOfEstimates	<div style="margin-bottom:8pt;margin-top:8pt;text-indent:18pt"><span style="color:#000000;font-family:'Times New Roman',sans-serif;font-size:10pt;font-weight:400;line-height:120%">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>
CY2023	us-gaap	Concentration Risk Credit Risk ConcentrationRiskCreditRisk	<span style="color:#000000;font-family:'Times New Roman',sans-serif;font-size:10pt;font-style:italic;font-weight:400;line-height:120%;padding-left:6.34pt">Concentration of Credit Risk</span><div style="margin-bottom:8pt;margin-top:8pt;text-indent:18pt"><span style="color:#000000;font-family:'Times New Roman',sans-serif;font-size:10pt;font-weight:400;line-height:120%">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, from time to time, exceed insurance limits (similar to Federal Deposit Insurance Corporation insurance limits).</span></div>
CY2022Q4	us-gaap	Equity Securities Fv Ni Cost EquitySecuritiesFvNiCost	394400000	usd
CY2023Q4	us-gaap	Equity Securities Fv Ni Cost EquitySecuritiesFvNiCost	35300000	usd
CY2022	us-gaap	Equity Securities Fv Ni Unrealized Gain EquitySecuritiesFvNiUnrealizedGain	59900000	usd
CY2023	us-gaap	Equity Securities Fv Ni Unrealized Gain EquitySecuritiesFvNiUnrealizedGain	2600000	usd
CY2022	us-gaap	Equity Securities Fv Ni Unrealized Loss EquitySecuritiesFvNiUnrealizedLoss	6400000	usd
CY2023	us-gaap	Equity Securities Fv Ni Unrealized Loss EquitySecuritiesFvNiUnrealizedLoss	0.0	usd
CY2022Q4	us-gaap	Equity Securities Fv Ni Current And Noncurrent EquitySecuritiesFvNiCurrentAndNoncurrent	447900000	usd
CY2023Q4	us-gaap	Equity Securities Fv Ni Current And Noncurrent EquitySecuritiesFvNiCurrentAndNoncurrent	37900000	usd
CY2022	us-gaap	Equity Securities Fv Ni Unrealized Gain Loss EquitySecuritiesFvNiUnrealizedGainLoss	35500000	usd
CY2023	us-gaap	Equity Securities Fv Ni Unrealized Gain Loss EquitySecuritiesFvNiUnrealizedGainLoss	2900000	usd
CY2022Q4	us-gaap	Available For Sale Debt Securities Amortized Cost Basis AvailableForSaleDebtSecuritiesAmortizedCostBasis	252300000	usd
CY2023Q4	us-gaap	Available For Sale Debt Securities Amortized Cost Basis AvailableForSaleDebtSecuritiesAmortizedCostBasis	405400000	usd
CY2022Q4	us-gaap	Trading Securities Debt Amortized Cost TradingSecuritiesDebtAmortizedCost	19700000	usd
CY2023Q4	us-gaap	Trading Securities Debt Amortized Cost TradingSecuritiesDebtAmortizedCost	17900000	usd
CY2022Q4	us-gaap	Available For Sale Debt Securities Accumulated Gross Unrealized Gain Before Tax AvailableForSaleDebtSecuritiesAccumulatedGrossUnrealizedGainBeforeTax	0	usd
CY2023Q4	us-gaap	Available For Sale Debt Securities Accumulated Gross Unrealized Gain Before Tax AvailableForSaleDebtSecuritiesAccumulatedGrossUnrealizedGainBeforeTax	0.0	usd
CY2022Q4	amg	Debt Securities Trading Accumulated Gross Unrealized Gain Before Tax DebtSecuritiesTradingAccumulatedGrossUnrealizedGainBeforeTax	0	usd
CY2023Q4	amg	Debt Securities Trading Accumulated Gross Unrealized Gain Before Tax DebtSecuritiesTradingAccumulatedGrossUnrealizedGainBeforeTax	0	usd
CY2022Q4	us-gaap	Available For Sale Debt Securities Accumulated Gross Unrealized Loss Before Tax AvailableForSaleDebtSecuritiesAccumulatedGrossUnrealizedLossBeforeTax	1300000	usd
CY2023Q4	us-gaap	Available For Sale Debt Securities Accumulated Gross Unrealized Loss Before Tax AvailableForSaleDebtSecuritiesAccumulatedGrossUnrealizedLossBeforeTax	100000	usd
CY2022Q4	amg	Debt Securities Trading Accumulated Gross Unrealized Loss Before Tax DebtSecuritiesTradingAccumulatedGrossUnrealizedLossBeforeTax	1700000	usd
CY2023Q4	amg	Debt Securities Trading Accumulated Gross Unrealized Loss Before Tax DebtSecuritiesTradingAccumulatedGrossUnrealizedLossBeforeTax	100000	usd
CY2022Q4	us-gaap	Available For Sale Securities Debt Securities AvailableForSaleSecuritiesDebtSecurities	251000000.0	usd
CY2023Q4	us-gaap	Available For Sale Securities Debt Securities AvailableForSaleSecuritiesDebtSecurities	405300000	usd
CY2022Q4	us-gaap	Trading Securities Debt TradingSecuritiesDebt	18000000.0	usd
CY2023Q4	us-gaap	Trading Securities Debt TradingSecuritiesDebt	17800000	usd
CY2022	us-gaap	Proceeds From Maturities Prepayments And Calls Of Available For Sale Securities ProceedsFromMaturitiesPrepaymentsAndCallsOfAvailableForSaleSecurities	0	usd
CY2023	us-gaap	Proceeds From Maturities Prepayments And Calls Of Available For Sale Securities ProceedsFromMaturitiesPrepaymentsAndCallsOfAvailableForSaleSecurities	511100000	usd
CY2022	us-gaap	Debt Securities Trading Unrealized Gain Loss DebtSecuritiesTradingUnrealizedGainLoss	-2200000	usd
CY2023	us-gaap	Debt Securities Trading Unrealized Gain Loss DebtSecuritiesTradingUnrealizedGainLoss	800000	usd
CY2022Q4	us-gaap	Fair Value Investments Entities That Calculate Net Asset Value Per Share Unfunded Committments FairValueInvestmentsEntitiesThatCalculateNetAssetValuePerShareUnfundedCommittments	158300000	usd
CY2023Q4	us-gaap	Fair Value Investments Entities That Calculate Net Asset Value Per Share Unfunded Committments FairValueInvestmentsEntitiesThatCalculateNetAssetValuePerShareUnfundedCommittments	187200000	usd
CY2023	amg	Fair Value Investments Entities That Calculate Na Vs Life Of Fund FairValueInvestmentsEntitiesThatCalculateNAVsLifeOfFund	P15Y
CY2022Q4	amg	Equity Securities Without Readily Determinable Fair Value Cost EquitySecuritiesWithoutReadilyDeterminableFairValueCost	8500000	usd
CY2023Q4	amg	Equity Securities Without Readily Determinable Fair Value Cost EquitySecuritiesWithoutReadilyDeterminableFairValueCost	8500000	usd
CY2022Q4	us-gaap	Equity Securities Without Readily Determinable Fair Value Upward Price Adjustment Cumulative Amount EquitySecuritiesWithoutReadilyDeterminableFairValueUpwardPriceAdjustmentCumulativeAmount	41900000	usd
CY2023Q4	us-gaap	Equity Securities Without Readily Determinable Fair Value Upward Price Adjustment Cumulative Amount EquitySecuritiesWithoutReadilyDeterminableFairValueUpwardPriceAdjustmentCumulativeAmount	41900000	usd
CY2023Q4	us-gaap	Equity Securities Without Readily Determinable Fair Value Amount EquitySecuritiesWithoutReadilyDeterminableFairValueAmount	50400000	usd
CY2023	us-gaap	Equity Securities Without Readily Determinable Fair Value Upward Price Adjustment Annual Amount EquitySecuritiesWithoutReadilyDeterminableFairValueUpwardPriceAdjustmentAnnualAmount	0	usd
CY2021Q4	us-gaap	Other Investments OtherInvestments	375200000	usd
CY2022Q4	us-gaap	Equity Securities Without Readily Determinable Fair Value Amount EquitySecuritiesWithoutReadilyDeterminableFairValueAmount	50400000	usd
CY2022	amg	Equity Securities Without Readily Determinable Fair Value Net Gain Loss EquitySecuritiesWithoutReadilyDeterminableFairValueNetGainLoss	0	usd
CY2022	amg	Other Investments Gain Loss Net OtherInvestmentsGainLossNet	1700000	usd
CY2023	amg	Equity Securities Without Readily Determinable Fair Value Net Gain Loss EquitySecuritiesWithoutReadilyDeterminableFairValueNetGainLoss	0	usd
CY2023	amg	Other Investments Gain Loss Net OtherInvestmentsGainLossNet	34200000	usd
CY2022	amg	Equity Securities Without Readily Determinable Fair Value Purchases And Commitments EquitySecuritiesWithoutReadilyDeterminableFairValuePurchasesAndCommitments	0	usd
CY2022	amg	Other Investments Purchases OtherInvestmentsPurchases	104300000	usd
CY2023	amg	Other Investments Purchases OtherInvestmentsPurchases	82500000	usd
CY2022	amg	Equity Securities Without Readily Determinable Fair Value Sales And Distributions EquitySecuritiesWithoutReadilyDeterminableFairValueSalesAndDistributions	0	usd
CY2022	amg	Other Investments Sales OtherInvestmentsSales	59600000	usd
CY2023Q4	us-gaap	Equity Securities Without Readily Determinable Fair Value Amount EquitySecuritiesWithoutReadilyDeterminableFairValueAmount	50400000	usd
CY2023Q4	us-gaap	Other Investments OtherInvestments	480900000	usd
CY2022Q4	us-gaap	Investments In Affiliates Subsidiaries Associates And Joint Ventures InvestmentsInAffiliatesSubsidiariesAssociatesAndJointVentures	2139500000	usd
CY2023Q4	us-gaap	Investments In Affiliates Subsidiaries Associates And Joint Ventures InvestmentsInAffiliatesSubsidiariesAssociatesAndJointVentures	2288500000	usd
CY2022Q4	us-gaap	Equity Method Investments EquityMethodInvestments	87900000	usd
CY2023Q4	us-gaap	Equity Method Investments EquityMethodInvestments	90300000	usd
CY2022Q4	us-gaap	Long Term Debt LongTermDebt	2535300000	usd
CY2023Q4	us-gaap	Long Term Debt LongTermDebt	2537500000	usd
CY2023Q4	amg	Investment Commitment Amount InvestmentCommitmentAmount	187200000	usd
CY2023Q4	amg	Deferred Payment Obligations Liability DeferredPaymentObligationsLiability	43300000	usd
CY2023Q4	amg	Deferred Payment Obligations Liability To Be Paid Year One DeferredPaymentObligationsLiabilityToBePaidYearOne	21700000	usd
CY2023Q4	amg	Deferred Payment Obligations Liability To Be Paid Year Two DeferredPaymentObligationsLiabilityToBePaidYearTwo	21600000	usd
CY2023Q4	amg	Contingent Consideration Liability ContingentConsiderationLiability	14700000	usd
CY2023Q4	amg	Contingent Consideration Liability To Be Paid Year One ContingentConsiderationLiabilityToBePaidYearOne	9500000	usd
CY2023Q4	amg	Contingent Consideration Liability To Be Paid Year Two ContingentConsiderationLiabilityToBePaidYearTwo	5200000	usd
CY2021Q4	us-gaap	Goodwill Goodwill	2689200000	usd
CY2022Q4	us-gaap	Goodwill Goodwill	2648700000	usd
CY2022	amg	Goodwill Deconsolidated GoodwillDeconsolidated	0	usd
CY2023	amg	Goodwill Deconsolidated GoodwillDeconsolidated	136500000	usd
CY2022	us-gaap	Goodwill Foreign Currency Translation Gain Loss GoodwillForeignCurrencyTranslationGainLoss	-40500000	usd
CY2023	us-gaap	Goodwill Foreign Currency Translation Gain Loss GoodwillForeignCurrencyTranslationGainLoss	16500000	usd
CY2023	us-gaap	Goodwill Other Increase Decrease GoodwillOtherIncreaseDecrease	-5100000	usd
CY2022Q4	us-gaap	Goodwill Goodwill	2648700000	usd
CY2023Q4	us-gaap	Goodwill Goodwill	2523600000	usd
	us-gaap	Goodwill Impairment Loss GoodwillImpairmentLoss	0	usd
CY2023	amg	Impairment Of Intangible Asset Indefinite Lived Excluding Goodwill Statement Of Income Or Comprehensive Income Extensible Enumeration Not Disclosed Flag ImpairmentOfIntangibleAssetIndefiniteLivedExcludingGoodwillStatementOfIncomeOrComprehensiveIncomeExtensibleEnumerationNotDisclosedFlag	Indefinite-lived
CY2023Q3	amg	Proceeds From Divestiture Of Interest In Subsidiaries And Affiliates Net Of Transaction Costs ProceedsFromDivestitureOfInterestInSubsidiariesAndAffiliatesNetOfTransactionCosts	287400000	usd
CY2023Q3	us-gaap	Gain Loss On Sale Of Business GainLossOnSaleOfBusiness	133100000	usd
CY2022Q4	amg	Number Of Affiliates Equity Method Investment NumberOfAffiliatesEquityMethodInvestment	20	affiliate
CY2023Q4	amg	Number Of Affiliates Equity Method Investment NumberOfAffiliatesEquityMethodInvestment	22	affiliate
CY2022Q4	us-gaap	Equity Method Investment Realized Gain Loss On Disposal EquityMethodInvestmentRealizedGainLossOnDisposal	641900000	usd
CY2021	us-gaap	Operating Lease Cost OperatingLeaseCost	33800000	usd
CY2022	us-gaap	Operating Lease Cost OperatingLeaseCost	38500000	usd
CY2023	us-gaap	Operating Lease Cost OperatingLeaseCost	36400000	usd
CY2021	us-gaap	Short Term Lease Cost ShortTermLeaseCost	800000	usd
CY2022	us-gaap	Short Term Lease Cost ShortTermLeaseCost	1000000.0	usd
CY2023	us-gaap	Short Term Lease Cost ShortTermLeaseCost	1100000	usd
CY2021	us-gaap	Variable Lease Cost VariableLeaseCost	0.0	usd
CY2022	us-gaap	Variable Lease Cost VariableLeaseCost	0.0	usd
CY2023	us-gaap	Variable Lease Cost VariableLeaseCost	0.0	usd
CY2021	us-gaap	Sublease Income SubleaseIncome	7900000	usd
CY2022	us-gaap	Sublease Income SubleaseIncome	7700000	usd
CY2023	us-gaap	Sublease Income SubleaseIncome	6500000	usd
CY2021	us-gaap	Lease Cost LeaseCost	26700000	usd
CY2022	us-gaap	Lease Cost LeaseCost	31800000	usd
CY2023	us-gaap	Lease Cost LeaseCost	31000000.0	usd
CY2022Q4	us-gaap	Operating Lease Weighted Average Remaining Lease Term1 OperatingLeaseWeightedAverageRemainingLeaseTerm1	P8Y
CY2023Q4	us-gaap	Operating Lease Weighted Average Remaining Lease Term1 OperatingLeaseWeightedAverageRemainingLeaseTerm1	P7Y
CY2022Q4	us-gaap	Operating Lease Weighted Average Discount Rate Percent OperatingLeaseWeightedAverageDiscountRatePercent	0.03
CY2023Q4	us-gaap	Operating Lease Weighted Average Discount Rate Percent OperatingLeaseWeightedAverageDiscountRatePercent	0.03
CY2023Q4	us-gaap	Lessee Operating Lease Liability Payments Due Next Twelve Months LesseeOperatingLeaseLiabilityPaymentsDueNextTwelveMonths	39100000	usd
CY2023Q4	us-gaap	Lessee Operating Lease Liability Payments Due Year Two LesseeOperatingLeaseLiabilityPaymentsDueYearTwo	35000000.0	usd
CY2023Q4	us-gaap	Lessee Operating Lease Liability Payments Due Year Three LesseeOperatingLeaseLiabilityPaymentsDueYearThree	25900000	usd
CY2023Q4	us-gaap	Lessee Operating Lease Liability Payments Due Year Four LesseeOperatingLeaseLiabilityPaymentsDueYearFour	21900000	usd
CY2023Q4	us-gaap	Lessee Operating Lease Liability Payments Due Year Five LesseeOperatingLeaseLiabilityPaymentsDueYearFive	21800000	usd
CY2023Q4	us-gaap	Lessee Operating Lease Liability Payments Due After Year Five LesseeOperatingLeaseLiabilityPaymentsDueAfterYearFive	68300000	usd
CY2023Q4	us-gaap	Lessee Operating Lease Liability Payments Due LesseeOperatingLeaseLiabilityPaymentsDue	212000000.0	usd
CY2023Q4	us-gaap	Lessee Operating Lease Liability Undiscounted Excess Amount LesseeOperatingLeaseLiabilityUndiscountedExcessAmount	29300000	usd
CY2022Q4	us-gaap	Property Plant And Equipment Gross PropertyPlantAndEquipmentGross	229900000	usd
CY2023Q4	us-gaap	Property Plant And Equipment Gross PropertyPlantAndEquipmentGross	213300000	usd
CY2022Q4	us-gaap	Accumulated Depreciation Depletion And Amortization Property Plant And Equipment AccumulatedDepreciationDepletionAndAmortizationPropertyPlantAndEquipment	161400000	usd
CY2023Q4	us-gaap	Accumulated Depreciation Depletion And Amortization Property Plant And Equipment AccumulatedDepreciationDepletionAndAmortizationPropertyPlantAndEquipment	146000000.0	usd
CY2022Q4	us-gaap	Property Plant And Equipment Net PropertyPlantAndEquipmentNet	68500000	usd
CY2023Q4	us-gaap	Property Plant And Equipment Net PropertyPlantAndEquipmentNet	67300000	usd
CY2022Q4	us-gaap	Employee Related Liabilities Current And Noncurrent EmployeeRelatedLiabilitiesCurrentAndNoncurrent	378700000	usd
CY2023Q4	us-gaap	Employee Related Liabilities Current And Noncurrent EmployeeRelatedLiabilitiesCurrentAndNoncurrent	309300000	usd
CY2022Q4	us-gaap	Accrued Income Taxes AccruedIncomeTaxes	224400000	usd
CY2023Q4	us-gaap	Accrued Income Taxes AccruedIncomeTaxes	62300000	usd
CY2022Q4	us-gaap	Other Accrued Liabilities Current And Noncurrent OtherAccruedLiabilitiesCurrentAndNoncurrent	175200000	usd
CY2023Q4	us-gaap	Other Accrued Liabilities Current And Noncurrent OtherAccruedLiabilitiesCurrentAndNoncurrent	256900000	usd
CY2022Q4	us-gaap	Accounts Payable And Accrued Liabilities Current And Noncurrent AccountsPayableAndAccruedLiabilitiesCurrentAndNoncurrent	778300000	usd
CY2023Q4	us-gaap	Accounts Payable And Accrued Liabilities Current And Noncurrent AccountsPayableAndAccruedLiabilitiesCurrentAndNoncurrent	628500000	usd
CY2023Q4	amg	Common Stock Voting Rights Percent CommonStockVotingRightsPercent	0.05
CY2023Q4	us-gaap	Stock Repurchase Program Remaining Number Of Shares Authorized To Be Repurchased StockRepurchaseProgramRemainingNumberOfSharesAuthorizedToBeRepurchased	4200000	shares
CY2023Q4	us-gaap	Stock Repurchase Program Remaining Number Of Shares Authorized To Be Repurchased StockRepurchaseProgramRemainingNumberOfSharesAuthorizedToBeRepurchased	4200000	shares
CY2023Q4	us-gaap	Stock Repurchase Program Remaining Number Of Shares Authorized To Be Repurchased StockRepurchaseProgramRemainingNumberOfSharesAuthorizedToBeRepurchased	4200000	shares
CY2022Q4	amg	Accelerated Share Repurchase Upfront Payment AcceleratedShareRepurchaseUpfrontPayment	225000000	usd
CY2022Q4	amg	Accelerated Share Repurchase Stock Repurchased During Period Shares AcceleratedShareRepurchaseStockRepurchasedDuringPeriodShares	1100000	shares
CY2022Q4	amg	Accelerated Share Repurchase Percentage Of Shares Received AcceleratedShareRepurchasePercentageOfSharesReceived	0.80
CY2023Q2	amg	Accelerated Share Repurchase Stock Repurchased During Period Shares AcceleratedShareRepurchaseStockRepurchasedDuringPeriodShares	400000	shares
	us-gaap	Treasury Stock Shares Acquired TreasuryStockSharesAcquired	1500000	shares
	us-gaap	Treasury Stock Acquired Average Cost Per Share TreasuryStockAcquiredAverageCostPerShare	147.29
CY2023Q4	us-gaap	Share Based Compensation Arrangement By Share Based Payment Award Options Exercisable Weighted Average Exercise Price ShareBasedCompensationArrangementByShareBasedPaymentAwardOptionsExercisableWeightedAverageExercisePrice	119.54
CY2023	us-gaap	Sharebased Compensation Arrangement By Sharebased Payment Award Options Exercisable Weighted Average Remaining Contractual Term1 SharebasedCompensationArrangementBySharebasedPaymentAwardOptionsExercisableWeightedAverageRemainingContractualTerm1	P2Y9M18D
CY2021	us-gaap	Sharebased Compensation Arrangement By Sharebased Payment Award Options Vested In Period Fair Value1 SharebasedCompensationArrangementBySharebasedPaymentAwardOptionsVestedInPeriodFairValue1	2000000	usd
CY2022	us-gaap	Sharebased Compensation Arrangement By Sharebased Payment Award Options Vested In Period Fair Value1 SharebasedCompensationArrangementBySharebasedPaymentAwardOptionsVestedInPeriodFairValue1	1800000	usd
CY2021	us-gaap	Allocated Share Based Compensation Expense AllocatedShareBasedCompensationExpense	63400000	usd
CY2021	us-gaap	Employee Service Share Based Compensation Tax Benefit From Compensation Expense EmployeeServiceShareBasedCompensationTaxBenefitFromCompensationExpense	8000000.0	usd
CY2022	us-gaap	Allocated Share Based Compensation Expense AllocatedShareBasedCompensationExpense	62400000	usd
CY2022	us-gaap	Employee Service Share Based Compensation Tax Benefit From Compensation Expense EmployeeServiceShareBasedCompensationTaxBenefitFromCompensationExpense	7600000	usd
CY2023	us-gaap	Allocated Share Based Compensation Expense AllocatedShareBasedCompensationExpense	59400000	usd
CY2023	us-gaap	Employee Service Share Based Compensation Tax Benefit From Compensation Expense EmployeeServiceShareBasedCompensationTaxBenefitFromCompensationExpense	7400000	usd
CY2021	amg	Excess Tax Benefit Deficiency From Share Based Compensation ExcessTaxBenefitDeficiencyFromShareBasedCompensation	-200000	usd
CY2022	amg	Excess Tax Benefit Deficiency From Share Based Compensation ExcessTaxBenefitDeficiencyFromShareBasedCompensation	1800000	usd
CY2023	amg	Excess Tax Benefit Deficiency From Share Based Compensation ExcessTaxBenefitDeficiencyFromShareBasedCompensation	4400000	usd
CY2022Q4	us-gaap	Employee Service Share Based Compensation Nonvested Awards Total Compensation Cost Not Yet Recognized EmployeeServiceShareBasedCompensationNonvestedAwardsTotalCompensationCostNotYetRecognized	64700000	usd
CY2023Q4	us-gaap	Employee Service Share Based Compensation Nonvested Awards Total Compensation Cost Not Yet Recognized EmployeeServiceShareBasedCompensationNonvestedAwardsTotalCompensationCostNotYetRecognized	54400000	usd
CY2023	us-gaap	Employee Service Share Based Compensation Nonvested Awards Total Compensation Cost Not Yet Recognized Period For Recognition1 EmployeeServiceShareBasedCompensationNonvestedAwardsTotalCompensationCostNotYetRecognizedPeriodForRecognition1	P2Y
CY2021	us-gaap	Share Based Compensation Arrangement By Share Based Payment Award Equity Instruments Other Than Options Vested In Period Total Fair Value ShareBasedCompensationArrangementByShareBasedPaymentAwardEquityInstrumentsOtherThanOptionsVestedInPeriodTotalFairValue	51700000	usd
CY2022	us-gaap	Share Based Compensation Arrangement By Share Based Payment Award Equity Instruments Other Than Options Vested In Period Total Fair Value ShareBasedCompensationArrangementByShareBasedPaymentAwardEquityInstrumentsOtherThanOptionsVestedInPeriodTotalFairValue	54600000	usd
CY2023	us-gaap	Share Based Compensation Arrangement By Share Based Payment Award Equity Instruments Other Than Options Vested In Period Total Fair Value ShareBasedCompensationArrangementByShareBasedPaymentAwardEquityInstrumentsOtherThanOptionsVestedInPeriodTotalFairValue	86200000	usd
CY2022Q4	us-gaap	Share Based Compensation Arrangement By Share Based Payment Award Options Outstanding Number ShareBasedCompensationArrangementByShareBasedPaymentAwardOptionsOutstandingNumber	3200000	shares
CY2022Q4	us-gaap	Share Based Compensation Arrangement By Share Based Payment Award Options Outstanding Weighted Average Exercise Price ShareBasedCompensationArrangementByShareBasedPaymentAwardOptionsOutstandingWeightedAverageExercisePrice	76.81
CY2023	us-gaap	Share Based Compensation Arrangement By Share Based Payment Award Options Grants In Period Gross ShareBasedCompensationArrangementByShareBasedPaymentAwardOptionsGrantsInPeriodGross	0	shares
CY2023	us-gaap	Share Based Compensation Arrangements By Share Based Payment Award Options Grants In Period Weighted Average Exercise Price ShareBasedCompensationArrangementsByShareBasedPaymentAwardOptionsGrantsInPeriodWeightedAverageExercisePrice	0
CY2023	us-gaap	Stock Issued During Period Shares Stock Options Exercised StockIssuedDuringPeriodSharesStockOptionsExercised	0.0	shares
CY2023	us-gaap	Share Based Compensation Arrangements By Share Based Payment Award Options Exercises In Period Weighted Average Exercise Price ShareBasedCompensationArrangementsByShareBasedPaymentAwardOptionsExercisesInPeriodWeightedAverageExercisePrice	127.77
CY2023	us-gaap	Share Based Compensation Arrangement By Share Based Payment Award Options Forfeitures In Period ShareBasedCompensationArrangementByShareBasedPaymentAwardOptionsForfeituresInPeriod	0	shares
CY2023	us-gaap	Share Based Compensation Arrangements By Share Based Payment Award Options Forfeitures In Period Weighted Average Exercise Price ShareBasedCompensationArrangementsByShareBasedPaymentAwardOptionsForfeituresInPeriodWeightedAverageExercisePrice	0
CY2023	us-gaap	Share Based Compensation Arrangement By Share Based Payment Award Options Expirations In Period ShareBasedCompensationArrangementByShareBasedPaymentAwardOptionsExpirationsInPeriod	0	shares
CY2023	us-gaap	Share Based Compensation Arrangements By Share Based Payment Award Options Expirations In Period Weighted Average Exercise Price ShareBasedCompensationArrangementsByShareBasedPaymentAwardOptionsExpirationsInPeriodWeightedAverageExercisePrice	0
CY2023	amg	Share Based Compensation Arrangement By Share Based Payment Award Options Period Increase Decrease Performance Condition Changes ShareBasedCompensationArrangementByShareBasedPaymentAwardOptionsPeriodIncreaseDecreasePerformanceConditionChanges	0	shares
CY2023	amg	Share Based Compensation Arrangements By Share Based Payment Award Options Performance Condition Changes Weighted Average Exercise Price ShareBasedCompensationArrangementsByShareBasedPaymentAwardOptionsPerformanceConditionChangesWeightedAverageExercisePrice	0
CY2023Q4	us-gaap	Share Based Compensation Arrangement By Share Based Payment Award Options Outstanding Number ShareBasedCompensationArrangementByShareBasedPaymentAwardOptionsOutstandingNumber	3200000	shares
CY2023Q4	us-gaap	Share Based Compensation Arrangement By Share Based Payment Award Options Outstanding Weighted Average Exercise Price ShareBasedCompensationArrangementByShareBasedPaymentAwardOptionsOutstandingWeightedAverageExercisePrice	76.74
CY2023	us-gaap	Sharebased Compensation Arrangement By Sharebased Payment Award Options Outstanding Weighted Average Remaining Contractual Term2 SharebasedCompensationArrangementBySharebasedPaymentAwardOptionsOutstandingWeightedAverageRemainingContractualTerm2	P2Y8M12D
CY2023Q4	us-gaap	Share Based Compensation Arrangement By Share Based Payment Award Options Exercisable Number ShareBasedCompensationArrangementByShareBasedPaymentAwardOptionsExercisableNumber	0.0	shares
CY2023	us-gaap	Sharebased Compensation Arrangement By Sharebased Payment Award Options Vested In Period Fair Value1 SharebasedCompensationArrangementBySharebasedPaymentAwardOptionsVestedInPeriodFairValue1	0	usd
CY2021	us-gaap	Share Based Compensation Arrangement By Share Based Payment Award Options Exercises In Period Total Intrinsic Value ShareBasedCompensationArrangementByShareBasedPaymentAwardOptionsExercisesInPeriodTotalIntrinsicValue	13400000	usd
CY2022	us-gaap	Share Based Compensation Arrangement By Share Based Payment Award Options Exercises In Period Total Intrinsic Value ShareBasedCompensationArrangementByShareBasedPaymentAwardOptionsExercisesInPeriodTotalIntrinsicValue	1200000	usd
CY2023	us-gaap	Share Based Compensation Arrangement By Share Based Payment Award Options Exercises In Period Total Intrinsic Value ShareBasedCompensationArrangementByShareBasedPaymentAwardOptionsExercisesInPeriodTotalIntrinsicValue	200000	usd
CY2021	us-gaap	Proceeds From Stock Options Exercised ProceedsFromStockOptionsExercised	3600000	usd
CY2022	us-gaap	Proceeds From Stock Options Exercised ProceedsFromStockOptionsExercised	2600000	usd
CY2023	us-gaap	Proceeds From Stock Options Exercised ProceedsFromStockOptionsExercised	0	usd
CY2023Q4	us-gaap	Sharebased Compensation Arrangement By Sharebased Payment Award Options Exercisable Intrinsic Value1 SharebasedCompensationArrangementBySharebasedPaymentAwardOptionsExercisableIntrinsicValue1	1900000	usd
CY2021	us-gaap	Share Based Compensation Arrangement By Share Based Payment Award Options Grants In Period Weighted Average Grant Date Fair Value ShareBasedCompensationArrangementByShareBasedPaymentAwardOptionsGrantsInPeriodWeightedAverageGrantDateFairValue	54.19
CY2022	us-gaap	Share Based Compensation Arrangement By Share Based Payment Award Options Grants In Period Weighted Average Grant Date Fair Value ShareBasedCompensationArrangementByShareBasedPaymentAwardOptionsGrantsInPeriodWeightedAverageGrantDateFairValue	47.84
CY2021Q4	us-gaap	Redeemable Noncontrolling Interest Equity Carrying Amount RedeemableNoncontrollingInterestEquityCarryingAmount	673900000	usd
CY2022Q4	us-gaap	Redeemable Noncontrolling Interest Equity Carrying Amount RedeemableNoncontrollingInterestEquityCarryingAmount	465400000	usd
CY2022	amg	Noncontrolling Interest Decrease From Affiliate Transaction NoncontrollingInterestDecreaseFromAffiliateTransaction	0	usd
CY2023	amg	Noncontrolling Interest Decrease From Affiliate Transaction NoncontrollingInterestDecreaseFromAffiliateTransaction	16800000	usd
CY2022	amg	Noncontrolling Interest Increase Decrease Attributable To Consolidated Partnerships NoncontrollingInterestIncreaseDecreaseAttributableToConsolidatedPartnerships	-4900000	usd
CY2023	amg	Noncontrolling Interest Increase Decrease Attributable To Consolidated Partnerships NoncontrollingInterestIncreaseDecreaseAttributableToConsolidatedPartnerships	-8300000	usd
CY2022	amg	Noncontrolling Interest Decreasefrom Transfersto Other Liabilities NoncontrollingInterestDecreasefromTransferstoOtherLiabilities	59600000	usd
CY2023	amg	Noncontrolling Interest Decreasefrom Transfersto Other Liabilities NoncontrollingInterestDecreasefromTransferstoOtherLiabilities	93500000	usd
CY2022	amg	Noncontrolling Interest Transfers To From Noncontrolling Interest Holders NoncontrollingInterestTransfersToFromNoncontrollingInterestHolders	1800000	usd
CY2023	amg	Noncontrolling Interest Transfers To From Noncontrolling Interest Holders NoncontrollingInterestTransfersToFromNoncontrollingInterestHolders	-8900000	usd
CY2022	amg	Redeemable Noncontrolling Interest Change In Redemption Value RedeemableNoncontrollingInterestChangeInRedemptionValue	145800000	usd
CY2023	amg	Redeemable Noncontrolling Interest Change In Redemption Value RedeemableNoncontrollingInterestChangeInRedemptionValue	-55500000	usd
CY2022Q4	us-gaap	Redeemable Noncontrolling Interest Equity Carrying Amount RedeemableNoncontrollingInterestEquityCarryingAmount	465400000	usd
CY2023Q4	us-gaap	Redeemable Noncontrolling Interest Equity Carrying Amount RedeemableNoncontrollingInterestEquityCarryingAmount	393400000	usd
CY2021	us-gaap	Payments Of Dividends Minority Interest PaymentsOfDividendsMinorityInterest	334300000	usd
CY2022	us-gaap	Payments Of Dividends Minority Interest PaymentsOfDividendsMinorityInterest	341900000	usd
CY2023	us-gaap	Payments Of Dividends Minority Interest PaymentsOfDividendsMinorityInterest	271300000	usd
CY2021	amg	Proceeds From Payments For Affiliate Equity Issuances And Repurchases ProceedsFromPaymentsForAffiliateEquityIssuancesAndRepurchases	150500000	usd
CY2022	amg	Proceeds From Payments For Affiliate Equity Issuances And Repurchases ProceedsFromPaymentsForAffiliateEquityIssuancesAndRepurchases	61500000	usd
CY2023	amg	Proceeds From Payments For Affiliate Equity Issuances And Repurchases ProceedsFromPaymentsForAffiliateEquityIssuancesAndRepurchases	67400000	usd
CY2021	amg	Proceeds From Affiliate Equity Issuances ProceedsFromAffiliateEquityIssuances	117700000	usd
CY2022	amg	Proceeds From Affiliate Equity Issuances ProceedsFromAffiliateEquityIssuances	15200000	usd
CY2023	amg	Proceeds From Affiliate Equity Issuances ProceedsFromAffiliateEquityIssuances	13400000	usd
CY2021	amg	Affiliate Equity Compensation Expense Including Portion Attributable To Noncontrolling Interest AffiliateEquityCompensationExpenseIncludingPortionAttributableToNoncontrollingInterest	63300000	usd
CY2022	amg	Affiliate Equity Compensation Expense Including Portion Attributable To Noncontrolling Interest AffiliateEquityCompensationExpenseIncludingPortionAttributableToNoncontrollingInterest	51400000	usd
CY2023	amg	Affiliate Equity Compensation Expense Including Portion Attributable To Noncontrolling Interest AffiliateEquityCompensationExpenseIncludingPortionAttributableToNoncontrollingInterest	52700000	usd
CY2021	us-gaap	Net Income Loss NetIncomeLoss	565700000	usd
CY2022	us-gaap	Net Income Loss NetIncomeLoss	1145900000	usd
CY2023	us-gaap	Net Income Loss NetIncomeLoss	672900000	usd
CY2021	amg	Adjustments To Additional Paid In Capital Increase Decrease In Carrying Amount Of Redeemable Noncontrolling Interests AdjustmentsToAdditionalPaidInCapitalIncreaseDecreaseInCarryingAmountOfRedeemableNoncontrollingInterests	17500000	usd
CY2022	amg	Adjustments To Additional Paid In Capital Increase Decrease In Carrying Amount Of Redeemable Noncontrolling Interests AdjustmentsToAdditionalPaidInCapitalIncreaseDecreaseInCarryingAmountOfRedeemableNoncontrollingInterests	200000	usd
CY2023	amg	Adjustments To Additional Paid In Capital Increase Decrease In Carrying Amount Of Redeemable Noncontrolling Interests AdjustmentsToAdditionalPaidInCapitalIncreaseDecreaseInCarryingAmountOfRedeemableNoncontrollingInterests	13500000	usd
CY2021	amg	Adjustments To Additional Paid In Capital Decrease In Carrying Amount Of Redeemable Noncontrolling Interests AdjustmentsToAdditionalPaidInCapitalDecreaseInCarryingAmountOfRedeemableNoncontrollingInterests	63200000	usd
CY2022	amg	Adjustments To Additional Paid In Capital Decrease In Carrying Amount Of Redeemable Noncontrolling Interests AdjustmentsToAdditionalPaidInCapitalDecreaseInCarryingAmountOfRedeemableNoncontrollingInterests	38200000	usd
CY2023	amg	Adjustments To Additional Paid In Capital Decrease In Carrying Amount Of Redeemable Noncontrolling Interests AdjustmentsToAdditionalPaidInCapitalDecreaseInCarryingAmountOfRedeemableNoncontrollingInterests	50400000	usd
CY2021	amg	Increase Decrease In Equity Due To Profit Loss And Net Transfers With Noncontrolling Interests IncreaseDecreaseInEquityDueToProfitLossAndNetTransfersWithNoncontrollingInterests	485000000.0	usd
CY2022	amg	Increase Decrease In Equity Due To Profit Loss And Net Transfers With Noncontrolling Interests IncreaseDecreaseInEquityDueToProfitLossAndNetTransfersWithNoncontrollingInterests	1107500000	usd
CY2023	amg	Increase Decrease In Equity Due To Profit Loss And Net Transfers With Noncontrolling Interests IncreaseDecreaseInEquityDueToProfitLossAndNetTransfersWithNoncontrollingInterests	609000000.0	usd
CY2021	us-gaap	Defined Contribution Plan Employer Discretionary Contribution Amount DefinedContributionPlanEmployerDiscretionaryContributionAmount	19100000	usd
CY2022	us-gaap	Defined Contribution Plan Employer Discretionary Contribution Amount DefinedContributionPlanEmployerDiscretionaryContributionAmount	20900000	usd
CY2023	us-gaap	Defined Contribution Plan Employer Discretionary Contribution Amount DefinedContributionPlanEmployerDiscretionaryContributionAmount	24800000	usd
CY2021	us-gaap	Income Tax Expense Benefit IncomeTaxExpenseBenefit	251000000.0	usd
CY2022	us-gaap	Income Tax Expense Benefit IncomeTaxExpenseBenefit	358300000	usd
CY2023	us-gaap	Income Tax Expense Benefit IncomeTaxExpenseBenefit	185300000	usd
CY2021	us-gaap	Current Federal Tax Expense Benefit CurrentFederalTaxExpenseBenefit	73100000	usd
CY2022	us-gaap	Current Federal Tax Expense Benefit CurrentFederalTaxExpenseBenefit	222900000	usd
CY2023	us-gaap	Current Federal Tax Expense Benefit CurrentFederalTaxExpenseBenefit	105200000	usd
CY2021	us-gaap	Current State And Local Tax Expense Benefit CurrentStateAndLocalTaxExpenseBenefit	19600000	usd
CY2022	us-gaap	Current State And Local Tax Expense Benefit CurrentStateAndLocalTaxExpenseBenefit	30600000	usd
CY2023	us-gaap	Current State And Local Tax Expense Benefit CurrentStateAndLocalTaxExpenseBenefit	10800000	usd
CY2021	us-gaap	Current Foreign Tax Expense Benefit CurrentForeignTaxExpenseBenefit	67100000	usd
CY2022	us-gaap	Current Foreign Tax Expense Benefit CurrentForeignTaxExpenseBenefit	72800000	usd
CY2023	us-gaap	Current Foreign Tax Expense Benefit CurrentForeignTaxExpenseBenefit	37900000	usd
CY2021	us-gaap	Current Income Tax Expense Benefit CurrentIncomeTaxExpenseBenefit	159800000	usd
CY2022	us-gaap	Current Income Tax Expense Benefit CurrentIncomeTaxExpenseBenefit	326300000	usd
CY2023	us-gaap	Current Income Tax Expense Benefit CurrentIncomeTaxExpenseBenefit	153900000	usd
CY2021	us-gaap	Deferred Federal Income Tax Expense Benefit DeferredFederalIncomeTaxExpenseBenefit	55900000	usd
CY2022	us-gaap	Deferred Federal Income Tax Expense Benefit DeferredFederalIncomeTaxExpenseBenefit	30400000	usd
CY2023	us-gaap	Deferred Federal Income Tax Expense Benefit DeferredFederalIncomeTaxExpenseBenefit	27300000	usd
CY2021	us-gaap	Deferred State And Local Income Tax Expense Benefit DeferredStateAndLocalIncomeTaxExpenseBenefit	13000000.0	usd
CY2022	us-gaap	Deferred State And Local Income Tax Expense Benefit DeferredStateAndLocalIncomeTaxExpenseBenefit	9000000.0	usd
CY2023	us-gaap	Deferred State And Local Income Tax Expense Benefit DeferredStateAndLocalIncomeTaxExpenseBenefit	7000000.0	usd
CY2021	us-gaap	Deferred Foreign Income Tax Expense Benefit DeferredForeignIncomeTaxExpenseBenefit	22300000	usd
CY2022	us-gaap	Deferred Foreign Income Tax Expense Benefit DeferredForeignIncomeTaxExpenseBenefit	-7400000	usd
CY2023	us-gaap	Deferred Foreign Income Tax Expense Benefit DeferredForeignIncomeTaxExpenseBenefit	-2900000	usd
CY2021	us-gaap	Deferred Income Tax Expense Benefit DeferredIncomeTaxExpenseBenefit	91200000	usd
CY2022	us-gaap	Deferred Income Tax Expense Benefit DeferredIncomeTaxExpenseBenefit	32000000.0	usd
CY2023	us-gaap	Deferred Income Tax Expense Benefit DeferredIncomeTaxExpenseBenefit	31400000	usd
CY2021	us-gaap	Income Tax Expense Benefit IncomeTaxExpenseBenefit	251000000.0	usd
CY2022	us-gaap	Income Tax Expense Benefit IncomeTaxExpenseBenefit	358300000	usd
CY2023	us-gaap	Income Tax Expense Benefit IncomeTaxExpenseBenefit	185300000	usd
CY2021	us-gaap	Income Loss From Continuing Operations Before Income Taxes Domestic IncomeLossFromContinuingOperationsBeforeIncomeTaxesDomestic	698200000	usd
CY2022	us-gaap	Income Loss From Continuing Operations Before Income Taxes Domestic IncomeLossFromContinuingOperationsBeforeIncomeTaxesDomestic	639000000.0	usd
CY2023	us-gaap	Income Loss From Continuing Operations Before Income Taxes Domestic IncomeLossFromContinuingOperationsBeforeIncomeTaxesDomestic	782300000	usd
CY2021	us-gaap	Income Loss From Continuing Operations Before Income Taxes Foreign IncomeLossFromContinuingOperationsBeforeIncomeTaxesForeign	442800000	usd
CY2022	us-gaap	Income Loss From Continuing Operations Before Income Taxes Foreign IncomeLossFromContinuingOperationsBeforeIncomeTaxesForeign	1107400000	usd
CY2023	us-gaap	Income Loss From Continuing Operations Before Income Taxes Foreign IncomeLossFromContinuingOperationsBeforeIncomeTaxesForeign	309100000	usd
CY2021	us-gaap	Income Loss From Continuing Operations Before Income Taxes Minority Interest And Income Loss From Equity Method Investments IncomeLossFromContinuingOperationsBeforeIncomeTaxesMinorityInterestAndIncomeLossFromEquityMethodInvestments	1141000000	usd
CY2022	us-gaap	Income Loss From Continuing Operations Before Income Taxes Minority Interest And Income Loss From Equity Method Investments IncomeLossFromContinuingOperationsBeforeIncomeTaxesMinorityInterestAndIncomeLossFromEquityMethodInvestments	1746400000	usd
CY2023	us-gaap	Income Loss From Continuing Operations Before Income Taxes Minority Interest And Income Loss From Equity Method Investments IncomeLossFromContinuingOperationsBeforeIncomeTaxesMinorityInterestAndIncomeLossFromEquityMethodInvestments	1091400000	usd
CY2021	us-gaap	Effective Income Tax Rate Continuing Operations EffectiveIncomeTaxRateContinuingOperations	0.220
CY2022	us-gaap	Effective Income Tax Rate Continuing Operations EffectiveIncomeTaxRateContinuingOperations	0.205
CY2023	us-gaap	Effective Income Tax Rate Continuing Operations EffectiveIncomeTaxRateContinuingOperations	0.170
CY2022	us-gaap	Equity Method Investment Realized Gain Loss On Disposal EquityMethodInvestmentRealizedGainLossOnDisposal	641900000	usd
CY2022Q4	us-gaap	Deferred Tax Assets Tax Deferred Expense Compensation And Benefits DeferredTaxAssetsTaxDeferredExpenseCompensationAndBenefits	14600000	usd
CY2023Q4	us-gaap	Deferred Tax Assets Tax Deferred Expense Compensation And Benefits DeferredTaxAssetsTaxDeferredExpenseCompensationAndBenefits	15900000	usd
CY2022Q4	us-gaap	Deferred Tax Assets Operating Loss Carryforwards State And Local DeferredTaxAssetsOperatingLossCarryforwardsStateAndLocal	16400000	usd
CY2023Q4	us-gaap	Deferred Tax Assets Operating Loss Carryforwards State And Local DeferredTaxAssetsOperatingLossCarryforwardsStateAndLocal	14700000	usd
CY2022Q4	us-gaap	Deferred Tax Assets Operating Loss Carryforwards Foreign DeferredTaxAssetsOperatingLossCarryforwardsForeign	20000000.0	usd
CY2023Q4	us-gaap	Deferred Tax Assets Operating Loss Carryforwards Foreign DeferredTaxAssetsOperatingLossCarryforwardsForeign	19800000	usd
CY2022Q4	amg	Deferred Tax Assets Tax Benefit On Uncertain Tax Positions DeferredTaxAssetsTaxBenefitOnUncertainTaxPositions	12600000	usd
CY2023Q4	amg	Deferred Tax Assets Tax Benefit On Uncertain Tax Positions DeferredTaxAssetsTaxBenefitOnUncertainTaxPositions	10000000.0	usd
CY2022Q4	amg	Deferred Tax Assets Operating Lease Liability DeferredTaxAssetsOperatingLeaseLiability	6600000	usd
CY2023Q4	amg	Deferred Tax Assets Operating Lease Liability DeferredTaxAssetsOperatingLeaseLiability	4800000	usd
CY2022Q4	us-gaap	Deferred Tax Assets Tax Credit Carryforwards Foreign DeferredTaxAssetsTaxCreditCarryforwardsForeign	15400000	usd
CY2023Q4	us-gaap	Deferred Tax Assets Tax Credit Carryforwards Foreign DeferredTaxAssetsTaxCreditCarryforwardsForeign	16000000.0	usd
CY2022Q4	us-gaap	Deferred Tax Assets Other DeferredTaxAssetsOther	300000	usd
CY2023Q4	us-gaap	Deferred Tax Assets Other DeferredTaxAssetsOther	300000	usd
CY2022Q4	us-gaap	Deferred Tax Assets Gross DeferredTaxAssetsGross	85900000	usd
CY2023Q4	us-gaap	Deferred Tax Assets Gross DeferredTaxAssetsGross	81500000	usd
CY2022Q4	us-gaap	Deferred Tax Assets Valuation Allowance DeferredTaxAssetsValuationAllowance	48100000	usd
CY2023Q4	us-gaap	Deferred Tax Assets Valuation Allowance DeferredTaxAssetsValuationAllowance	47600000	usd
CY2022Q4	us-gaap	Deferred Tax Assets Net DeferredTaxAssetsNet	37800000	usd
CY2023Q4	us-gaap	Deferred Tax Assets Net DeferredTaxAssetsNet	33900000	usd
CY2022Q4	us-gaap	Deferred Tax Liabilities Goodwill And Intangible Assets Intangible Assets DeferredTaxLiabilitiesGoodwillAndIntangibleAssetsIntangibleAssets	280900000	usd
CY2023Q4	us-gaap	Deferred Tax Liabilities Goodwill And Intangible Assets Intangible Assets DeferredTaxLiabilitiesGoodwillAndIntangibleAssetsIntangibleAssets	295800000	usd
CY2022Q4	amg	Deferred Tax Liabilities Nondeductible Intangible Assets Amortization DeferredTaxLiabilitiesNondeductibleIntangibleAssetsAmortization	109800000	usd
CY2023Q4	amg	Deferred Tax Liabilities Nondeductible Intangible Assets Amortization DeferredTaxLiabilitiesNondeductibleIntangibleAssetsAmortization	97000000.0	usd
CY2022Q4	amg	Deferred Tax Liabilities Convertible Securities Interest DeferredTaxLiabilitiesConvertibleSecuritiesInterest	72400000	usd
CY2023Q4	amg	Deferred Tax Liabilities Convertible Securities Interest DeferredTaxLiabilitiesConvertibleSecuritiesInterest	83100000	usd
CY2022Q4	us-gaap	Deferred Tax Liabilities Leasing Arrangements DeferredTaxLiabilitiesLeasingArrangements	5100000	usd
CY2023Q4	us-gaap	Deferred Tax Liabilities Leasing Arrangements DeferredTaxLiabilitiesLeasingArrangements	3700000	usd
CY2022Q4	amg	Deferred Tax Liabilities Accrued Liabilities And Fixed Assets DeferredTaxLiabilitiesAccruedLiabilitiesAndFixedAssets	3000000.0	usd
CY2023Q4	amg	Deferred Tax Liabilities Accrued Liabilities And Fixed Assets DeferredTaxLiabilitiesAccruedLiabilitiesAndFixedAssets	2000000.0	usd
CY2022Q4	us-gaap	Deferred Tax Liabilities Tax Deferred Income DeferredTaxLiabilitiesTaxDeferredIncome	23400000	usd
CY2023Q4	us-gaap	Deferred Tax Liabilities Tax Deferred Income DeferredTaxLiabilitiesTaxDeferredIncome	10400000	usd
CY2022Q4	us-gaap	Deferred Tax Liabilities Other DeferredTaxLiabilitiesOther	4400000	usd
CY2023Q4	us-gaap	Deferred Tax Liabilities Other DeferredTaxLiabilitiesOther	2900000	usd
CY2022Q4	us-gaap	Deferred Income Tax Liabilities DeferredIncomeTaxLiabilities	499000000.0	usd
CY2023Q4	us-gaap	Deferred Income Tax Liabilities DeferredIncomeTaxLiabilities	494900000	usd
CY2022Q4	us-gaap	Deferred Tax Liabilities DeferredTaxLiabilities	461200000	usd
CY2023Q4	us-gaap	Deferred Tax Liabilities DeferredTaxLiabilities	461000000.0	usd
CY2023Q4	us-gaap	Deferred Tax Assets Tax Credit Carryforwards Foreign DeferredTaxAssetsTaxCreditCarryforwardsForeign	16000000	usd
CY2023Q4	us-gaap	Undistributed Earnings Of Foreign Subsidiaries UndistributedEarningsOfForeignSubsidiaries	347700000	usd
CY2020Q4	us-gaap	Unrecognized Tax Benefits UnrecognizedTaxBenefits	63500000	usd
CY2021Q4	us-gaap	Unrecognized Tax Benefits UnrecognizedTaxBenefits	52400000	usd
CY2022Q4	us-gaap	Unrecognized Tax Benefits UnrecognizedTaxBenefits	49600000	usd
CY2021	us-gaap	Unrecognized Tax Benefits Increases Resulting From Current Period Tax Positions UnrecognizedTaxBenefitsIncreasesResultingFromCurrentPeriodTaxPositions	800000	usd
CY2022	us-gaap	Unrecognized Tax Benefits Increases Resulting From Current Period Tax Positions UnrecognizedTaxBenefitsIncreasesResultingFromCurrentPeriodTaxPositions	600000	usd
CY2023	us-gaap	Unrecognized Tax Benefits Increases Resulting From Current Period Tax Positions UnrecognizedTaxBenefitsIncreasesResultingFromCurrentPeriodTaxPositions	6400000	usd
CY2021	us-gaap	Unrecognized Tax Benefits Increases Resulting From Prior Period Tax Positions UnrecognizedTaxBenefitsIncreasesResultingFromPriorPeriodTaxPositions	4600000	usd
CY2022	us-gaap	Unrecognized Tax Benefits Increases Resulting From Prior Period Tax Positions UnrecognizedTaxBenefitsIncreasesResultingFromPriorPeriodTaxPositions	4400000	usd
CY2023	us-gaap	Unrecognized Tax Benefits Increases Resulting From Prior Period Tax Positions UnrecognizedTaxBenefitsIncreasesResultingFromPriorPeriodTaxPositions	1000000.0	usd
CY2021	us-gaap	Unrecognized Tax Benefits Decreases Resulting From Prior Period Tax Positions UnrecognizedTaxBenefitsDecreasesResultingFromPriorPeriodTaxPositions	5600000	usd
CY2022	us-gaap	Unrecognized Tax Benefits Decreases Resulting From Prior Period Tax Positions UnrecognizedTaxBenefitsDecreasesResultingFromPriorPeriodTaxPositions	1000000.0	usd
CY2023	us-gaap	Unrecognized Tax Benefits Decreases Resulting From Prior Period Tax Positions UnrecognizedTaxBenefitsDecreasesResultingFromPriorPeriodTaxPositions	13500000	usd
CY2021	us-gaap	Unrecognized Tax Benefits Reductions Resulting From Lapse Of Applicable Statute Of Limitations UnrecognizedTaxBenefitsReductionsResultingFromLapseOfApplicableStatuteOfLimitations	5700000	usd
CY2022	us-gaap	Unrecognized Tax Benefits Reductions Resulting From Lapse Of Applicable Statute Of Limitations UnrecognizedTaxBenefitsReductionsResultingFromLapseOfApplicableStatuteOfLimitations	5500000	usd
CY2023	us-gaap	Unrecognized Tax Benefits Reductions Resulting From Lapse Of Applicable Statute Of Limitations UnrecognizedTaxBenefitsReductionsResultingFromLapseOfApplicableStatuteOfLimitations	4800000	usd
CY2021	us-gaap	Unrecognized Tax Benefits Decreases Resulting From Settlements With Taxing Authorities UnrecognizedTaxBenefitsDecreasesResultingFromSettlementsWithTaxingAuthorities	5500000	usd
CY2022	us-gaap	Unrecognized Tax Benefits Decreases Resulting From Settlements With Taxing Authorities UnrecognizedTaxBenefitsDecreasesResultingFromSettlementsWithTaxingAuthorities	0	usd
CY2023	us-gaap	Unrecognized Tax Benefits Decreases Resulting From Settlements With Taxing Authorities UnrecognizedTaxBenefitsDecreasesResultingFromSettlementsWithTaxingAuthorities	1300000	usd
CY2021	amg	Unrecognized Tax Benefits Increase Decrease Relatedto Foreign Exchange Rates UnrecognizedTaxBenefitsIncreaseDecreaseRelatedtoForeignExchangeRates	300000	usd
CY2022	amg	Unrecognized Tax Benefits Increase Decrease Relatedto Foreign Exchange Rates UnrecognizedTaxBenefitsIncreaseDecreaseRelatedtoForeignExchangeRates	-1300000	usd
CY2023	amg	Unrecognized Tax Benefits Increase Decrease Relatedto Foreign Exchange Rates UnrecognizedTaxBenefitsIncreaseDecreaseRelatedtoForeignExchangeRates	400000	usd
CY2021Q4	us-gaap	Unrecognized Tax Benefits UnrecognizedTaxBenefits	52400000	usd
CY2022Q4	us-gaap	Unrecognized Tax Benefits UnrecognizedTaxBenefits	49600000	usd
CY2023Q4	us-gaap	Unrecognized Tax Benefits UnrecognizedTaxBenefits	37800000	usd
CY2021Q4	us-gaap	Unrecognized Tax Benefits That Would Impact Effective Tax Rate UnrecognizedTaxBenefitsThatWouldImpactEffectiveTaxRate	52400000	usd
CY2022Q4	us-gaap	Unrecognized Tax Benefits That Would Impact Effective Tax Rate UnrecognizedTaxBenefitsThatWouldImpactEffectiveTaxRate	49600000	usd
CY2023Q4	us-gaap	Unrecognized Tax Benefits That Would Impact Effective Tax Rate UnrecognizedTaxBenefitsThatWouldImpactEffectiveTaxRate	37800000	usd
CY2023Q4	amg	Deferred Tax Assets Tax Benefit On Uncertain Tax Positions DeferredTaxAssetsTaxBenefitOnUncertainTaxPositions	10000000	usd
CY2021	us-gaap	Unrecognized Tax Benefits Income Tax Penalties And Interest Expense UnrecognizedTaxBenefitsIncomeTaxPenaltiesAndInterestExpense	-400000	usd
CY2022	us-gaap	Unrecognized Tax Benefits Income Tax Penalties And Interest Expense UnrecognizedTaxBenefitsIncomeTaxPenaltiesAndInterestExpense	2600000	usd
CY2023	us-gaap	Unrecognized Tax Benefits Income Tax Penalties And Interest Expense UnrecognizedTaxBenefitsIncomeTaxPenaltiesAndInterestExpense	800000	usd
CY2022Q4	us-gaap	Unrecognized Tax Benefits Income Tax Penalties And Interest Accrued UnrecognizedTaxBenefitsIncomeTaxPenaltiesAndInterestAccrued	13600000	usd
CY2023Q4	us-gaap	Unrecognized Tax Benefits Income Tax Penalties And Interest Accrued UnrecognizedTaxBenefitsIncomeTaxPenaltiesAndInterestAccrued	14400000	usd
CY2021	us-gaap	Net Income Loss Available To Common Stockholders Basic NetIncomeLossAvailableToCommonStockholdersBasic	565700000	usd
CY2022	us-gaap	Net Income Loss Available To Common Stockholders Basic NetIncomeLossAvailableToCommonStockholdersBasic	1145900000	usd
CY2023	us-gaap	Net Income Loss Available To Common Stockholders Basic NetIncomeLossAvailableToCommonStockholdersBasic	672900000	usd
CY2021	amg	Net Income Loss Other Noncontrolling Interests Redeemable NetIncomeLossOtherNoncontrollingInterestsRedeemable	0	usd
CY2022	amg	Net Income Loss Other Noncontrolling Interests Redeemable NetIncomeLossOtherNoncontrollingInterestsRedeemable	82900000	usd
CY2023	amg	Net Income Loss Other Noncontrolling Interests Redeemable NetIncomeLossOtherNoncontrollingInterestsRedeemable	49000000.0	usd
CY2021	us-gaap	Interest On Convertible Debt Net Of Tax InterestOnConvertibleDebtNetOfTax	18500000	usd
CY2022	us-gaap	Interest On Convertible Debt Net Of Tax InterestOnConvertibleDebtNetOfTax	14000000.0	usd
CY2023	us-gaap	Interest On Convertible Debt Net Of Tax InterestOnConvertibleDebtNetOfTax	13400000	usd
CY2021	us-gaap	Net Income Loss Available To Common Stockholders Diluted NetIncomeLossAvailableToCommonStockholdersDiluted	584200000	usd
CY2022	us-gaap	Net Income Loss Available To Common Stockholders Diluted NetIncomeLossAvailableToCommonStockholdersDiluted	1242800000	usd
CY2023	us-gaap	Net Income Loss Available To Common Stockholders Diluted NetIncomeLossAvailableToCommonStockholdersDiluted	735300000	usd
CY2021	us-gaap	Weighted Average Number Of Shares Outstanding Basic WeightedAverageNumberOfSharesOutstandingBasic	41500000	shares
CY2022	us-gaap	Weighted Average Number Of Shares Outstanding Basic WeightedAverageNumberOfSharesOutstandingBasic	38500000	shares
CY2023	us-gaap	Weighted Average Number Of Shares Outstanding Basic WeightedAverageNumberOfSharesOutstandingBasic	35100000	shares
CY2021	us-gaap	Incremental Common Shares Attributable To Share Based Payment Arrangements IncrementalCommonSharesAttributableToShareBasedPaymentArrangements	1200000	shares
CY2022	us-gaap	Incremental Common Shares Attributable To Share Based Payment Arrangements IncrementalCommonSharesAttributableToShareBasedPaymentArrangements	1300000	shares
CY2023	us-gaap	Incremental Common Shares Attributable To Share Based Payment Arrangements IncrementalCommonSharesAttributableToShareBasedPaymentArrangements	1700000	shares
CY2021	amg	Settlement Of Redeemable Non Controlling Interests Shares Issued SettlementOfRedeemableNonControllingInterestsSharesIssued	0	shares
CY2022	amg	Settlement Of Redeemable Non Controlling Interests Shares Issued SettlementOfRedeemableNonControllingInterestsSharesIssued	7400000	shares
CY2023	amg	Settlement Of Redeemable Non Controlling Interests Shares Issued SettlementOfRedeemableNonControllingInterestsSharesIssued	3700000	shares
CY2021	us-gaap	Incremental Common Shares Attributable To Conversion Of Debt Securities IncrementalCommonSharesAttributableToConversionOfDebtSecurities	2100000	shares
CY2022	us-gaap	Incremental Common Shares Attributable To Conversion Of Debt Securities IncrementalCommonSharesAttributableToConversionOfDebtSecurities	1800000	shares
CY2023	us-gaap	Incremental Common Shares Attributable To Conversion Of Debt Securities IncrementalCommonSharesAttributableToConversionOfDebtSecurities	1700000	shares
CY2021	us-gaap	Weighted Average Number Of Diluted Shares Outstanding WeightedAverageNumberOfDilutedSharesOutstanding	44800000	shares
CY2022	us-gaap	Weighted Average Number Of Diluted Shares Outstanding WeightedAverageNumberOfDilutedSharesOutstanding	49000000.0	shares
CY2023	us-gaap	Weighted Average Number Of Diluted Shares Outstanding WeightedAverageNumberOfDilutedSharesOutstanding	42200000	shares
CY2021	us-gaap	Other Comprehensive Income Loss Before Tax OtherComprehensiveIncomeLossBeforeTax	11200000	usd
CY2021	us-gaap	Other Comprehensive Income Loss Tax OtherComprehensiveIncomeLossTax	4000000.0	usd
CY2021	us-gaap	Other Comprehensive Income Loss Net Of Tax OtherComprehensiveIncomeLossNetOfTax	7200000	usd
CY2022	us-gaap	Other Comprehensive Income Loss Before Tax OtherComprehensiveIncomeLossBeforeTax	-145900000	usd
CY2022	us-gaap	Other Comprehensive Income Loss Tax OtherComprehensiveIncomeLossTax	-3100000	usd
CY2022	us-gaap	Other Comprehensive Income Loss Net Of Tax OtherComprehensiveIncomeLossNetOfTax	-142800000	usd
CY2023	us-gaap	Other Comprehensive Income Loss Before Tax OtherComprehensiveIncomeLossBeforeTax	45600000	usd
CY2023	us-gaap	Other Comprehensive Income Loss Tax OtherComprehensiveIncomeLossTax	3700000	usd
CY2023	us-gaap	Other Comprehensive Income Loss Net Of Tax OtherComprehensiveIncomeLossNetOfTax	41900000	usd
CY2022	us-gaap	Other Comprehensive Income Loss Before Reclassifications Net Of Tax OtherComprehensiveIncomeLossBeforeReclassificationsNetOfTax	-141800000	usd
CY2022	us-gaap	Reclassification From Accumulated Other Comprehensive Income Current Period Net Of Tax ReclassificationFromAccumulatedOtherComprehensiveIncomeCurrentPeriodNetOfTax	1000000.0	usd
CY2022	us-gaap	Other Comprehensive Income Loss Net Of Tax OtherComprehensiveIncomeLossNetOfTax	-142800000	usd
CY2023	us-gaap	Other Comprehensive Income Loss Before Reclassifications Net Of Tax OtherComprehensiveIncomeLossBeforeReclassificationsNetOfTax	43500000	usd
CY2023	us-gaap	Reclassification From Accumulated Other Comprehensive Income Current Period Net Of Tax ReclassificationFromAccumulatedOtherComprehensiveIncomeCurrentPeriodNetOfTax	1600000	usd
CY2023	us-gaap	Other Comprehensive Income Loss Net Of Tax OtherComprehensiveIncomeLossNetOfTax	41900000	usd
CY2021	us-gaap	Revenue From Contract With Customer Excluding Assessed Tax RevenueFromContractWithCustomerExcludingAssessedTax	2412400000	usd
CY2022	us-gaap	Revenue From Contract With Customer Excluding Assessed Tax RevenueFromContractWithCustomerExcludingAssessedTax	2329600000	usd
CY2023	us-gaap	Revenue From Contract With Customer Excluding Assessed Tax RevenueFromContractWithCustomerExcludingAssessedTax	2057800000	usd
CY2022Q4	us-gaap	Property Plant And Equipment Net PropertyPlantAndEquipmentNet	68500000	usd
CY2023Q4	us-gaap	Property Plant And Equipment Net PropertyPlantAndEquipmentNet	67300000	usd

Files In Submission

Name	View Source	Status
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0001004434-24-000010-index.html	Edgar Link	pending
0001004434-24-000010.txt	Edgar Link	pending
0001004434-24-000010-xbrl.zip	Edgar Link	pending
amg-20231231.htm	Edgar Link	pending
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amg-20231231_cal.xml	Edgar Link	unprocessable
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amg-20231231_lab.xml	Edgar Link	unprocessable
amg-20231231_pre.xml	Edgar Link	unprocessable
amg-20231231_htm.xml	Edgar Link	completed
amg_exhibit97x123123.htm	Edgar Link	pending
Financial_Report.xlsx	Edgar Link	pending
MetaLinks.json	Edgar Link	pending
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report.css	Edgar Link	pending
Show.js	Edgar Link	pending
FilingSummary.xml	Edgar Link	unprocessable

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$AMG
AFFILIATED MANAGERS GROUP, INC. Stock $amg

2024 Q1 Form 10-K Financial Statement

#000100443424000010 Filed on February 16, 2024

Income Statement

Balance Sheet

Cashflow Statement

Facts In Submission

Files In Submission

$AMG AFFILIATED MANAGERS GROUP, INC. Stock $amg

2024 Q1 Form 10-K Financial Statement

#000100443424000010 Filed on February 16, 2024

Income Statement

Balance Sheet

Cashflow Statement

Facts In Submission

Files In Submission

$AMG
AFFILIATED MANAGERS GROUP, INC. Stock $amg