$AMG
AFFILIATED MANAGERS GROUP, INC. Stock $amg

$amg Overview Financials Valuation SEC Filings Company Website

2024 Q4 Form 10-Q Financial Statement

#000100443424000049 Filed on November 07, 2024

Income Statement

Concept	2024 Q4	2024 Q3
Revenue		$516.4M
YoY Change		-1.68%
Cost Of Revenue
YoY Change
Gross Profit
YoY Change
Gross Profit Margin
Selling, General & Admin		$317.8M
YoY Change		248.85%
% of Gross Profit
Research & Development
YoY Change
% of Gross Profit
Depreciation & Amortization		$10.60M
YoY Change		-31.61%
% of Gross Profit
Operating Expenses		$340.0M
YoY Change		-4.87%
Operating Profit
YoY Change
Interest Expense		$40.70M
YoY Change		30.87%
% of Operating Profit
Other Income/Expense, Net		$0.00
YoY Change		-100.0%
Pretax Income		$217.1M
YoY Change		-40.31%
Income Tax		$31.30M
% Of Pretax Income		14.42%
Net Earnings		$123.6M
YoY Change		-43.04%
Net Earnings / Revenue		23.93%
Basic Earnings Per Share		$4.11
Diluted Earnings Per Share		$3.53
COMMON SHARES
Basic Shares Outstanding	30.23M shares	29.81M shares
Diluted Shares Outstanding		35.00M shares

Balance Sheet

Concept	2024 Q4	2024 Q3
SHORT-TERM ASSETS
Cash & Short-Term Investments		$1.011B
YoY Change		-30.85%
Cash & Equivalents		$1.011B
Short-Term Investments		$66.10M
Other Short-Term Assets
YoY Change
Inventory
Prepaid Expenses
Receivables		$457.1M
Other Receivables		$0.00
Total Short-Term Assets		$1.468B
YoY Change		2.78%
LONG-TERM ASSETS
Property, Plant & Equipment		$61.00M
YoY Change		-4.39%
Goodwill		$2.532B
YoY Change		0.92%
Intangibles		$1.807B
YoY Change		-0.13%
Long-Term Investments		$2.747B
YoY Change		3007.81%
Other Assets
YoY Change
Total Long-Term Assets		$7.435B
YoY Change		-1.85%
TOTAL ASSETS
Total Short-Term Assets		$1.468B
Total Long-Term Assets		$7.435B
Total Assets		$8.903B
YoY Change		-1.12%
SHORT-TERM LIABILITIES
YoY Change
Accounts Payable		$625.7M
YoY Change		-1.65%
Accrued Expenses
YoY Change
Deferred Revenue
YoY Change
Short-Term Debt		$0.00
YoY Change
Long-Term Debt Due
YoY Change
Total Short-Term Liabilities		$625.7M
YoY Change		-1.65%
LONG-TERM LIABILITIES
Long-Term Debt		$2.620B
YoY Change		3.26%
Other Long-Term Liabilities		$464.5M
YoY Change		-3.69%
Total Long-Term Liabilities		$3.084B
YoY Change		2.15%
TOTAL LIABILITIES
Total Short-Term Liabilities		$625.7M
Total Long-Term Liabilities		$3.084B
Total Liabilities		$5.587B
YoY Change		36.03%
SHAREHOLDERS EQUITY
Retained Earnings		$6.738B
YoY Change		8.79%
Common Stock		$711.9M
YoY Change		-1.52%
Preferred Stock
YoY Change
Treasury Stock (at cost)
YoY Change
Treasury Stock Shares
Shareholders Equity		$3.316B
YoY Change
Total Liabilities & Shareholders Equity		$8.903B
YoY Change		-1.12%

Cashflow Statement

Concept	2024 Q4	2024 Q3
OPERATING ACTIVITIES
Net Income		$123.6M
YoY Change		-43.04%
Depreciation, Depletion And Amortization		$10.60M
YoY Change		-31.61%
Cash From Operating Activities		$270.2M
YoY Change		-7.47%
INVESTING ACTIVITIES
Capital Expenditures		$700.0K
YoY Change		-73.08%
Acquisitions
YoY Change
Other Investing Activities		$56.50M
YoY Change		-70.17%
Cash From Investing Activities		$55.80M
YoY Change		-70.13%
FINANCING ACTIVITIES
Cash Dividend Paid
YoY Change
Common Stock Issuance & Retirement, Net
YoY Change
Debt Paid & Issued, Net
YoY Change
Cash From Financing Activities		-188.0M
YoY Change		-27.36%
NET CHANGE
Cash From Operating Activities		270.2M
Cash From Investing Activities		55.80M
Cash From Financing Activities		-188.0M
Net Change In Cash		138.0M
YoY Change		-37.27%
FREE CASH FLOW
Cash From Operating Activities		$270.2M
Capital Expenditures		$700.0K
Free Cash Flow		$269.5M
YoY Change		-6.88%

Facts In Submission

Frame	Concept Type	Concept / XBRL Key	Value	Unit
	dei	Document Quarterly Report DocumentQuarterlyReport	true
	dei	Document Period End Date DocumentPeriodEndDate	2024-09-30
	dei	Document Transition Report DocumentTransitionReport	false
	dei	Entity File Number EntityFileNumber	001-13459
	dei	Entity Registrant Name EntityRegistrantName	AFFILIATED MANAGERS GROUP, INC.
	dei	Entity Incorporation State Country Code EntityIncorporationStateCountryCode	DE
	dei	Entity Tax Identification Number EntityTaxIdentificationNumber	04-3218510
	dei	Entity Address Address Line1 EntityAddressAddressLine1	777 South Flagler Drive
	dei	Entity Address City Or Town EntityAddressCityOrTown	West Palm Beach
	dei	Entity Address State Or Province EntityAddressStateOrProvince	FL
	dei	Entity Address Postal Zip Code EntityAddressPostalZipCode	33401
	dei	City Area Code CityAreaCode	800
	dei	Local Phone Number LocalPhoneNumber	345-1100
CY2023Q3	amg	Amortizationand Impairmentsof Intangible Assets AmortizationandImpairmentsofIntangibleAssets	12500000	usd
CY2023Q3	amg	Depreciation And Other Amortization DepreciationAndOtherAmortization	3000000.0	usd
	dei	Document Type DocumentType	10-Q
CY2023Q3	us-gaap	Operating Expenses OperatingExpenses	357400000	usd
CY2023Q3	us-gaap	Income Loss From Equity Method Investments IncomeLossFromEquityMethodInvestments	39800000	usd
	us-gaap	Profit Loss ProfitLoss	661900000	usd
	amg	Amortizationand Impairmentsof Intangible Assets AmortizationandImpairmentsofIntangibleAssets	37500000	usd
	amg	Depreciation And Other Amortization DepreciationAndOtherAmortization	10000000.0	usd
	us-gaap	Deferred Income Tax Expense Benefit DeferredIncomeTaxExpenseBenefit	13000000.0	usd
	us-gaap	Income Loss From Equity Method Investments IncomeLossFromEquityMethodInvestments	154300000	usd
CY2023Q4	us-gaap	Cash Cash Equivalents Restricted Cash And Restricted Cash Equivalents CashCashEquivalentsRestrictedCashAndRestrictedCashEquivalents	813600000	usd
	us-gaap	Equity Securities Fv Ni Unrealized Gain Loss EquitySecuritiesFvNiUnrealizedGainLoss	3500000	usd
	us-gaap	Equity Securities Fv Ni Unrealized Gain Loss EquitySecuritiesFvNiUnrealizedGainLoss	1300000	usd
CY2024Q3	us-gaap	Equity Securities Fv Ni Unrealized Gain Loss EquitySecuritiesFvNiUnrealizedGainLoss	2000000	usd
CY2023Q3	us-gaap	Proceeds From Maturities Prepayments And Calls Of Available For Sale Securities ProceedsFromMaturitiesPrepaymentsAndCallsOfAvailableForSaleSecurities	178400000	usd
	us-gaap	Proceeds From Maturities Prepayments And Calls Of Available For Sale Securities ProceedsFromMaturitiesPrepaymentsAndCallsOfAvailableForSaleSecurities	280100000	usd
CY2023Q3	us-gaap	Labor And Related Expense LaborAndRelatedExpense	211800000	usd
CY2023Q3	us-gaap	Selling General And Administrative Expense SellingGeneralAndAdministrativeExpense	91100000	usd
CY2023Q3	us-gaap	Other Operating Income Expense Net OtherOperatingIncomeExpenseNet	-7900000	usd
CY2023Q3	us-gaap	Gain Loss On Sale Of Business GainLossOnSaleOfBusiness	133100000	usd
CY2023Q3	amg	Investment And Other Income Loss InvestmentAndOtherIncomeLoss	23000000.0	usd
CY2023Q3	us-gaap	Income Loss From Continuing Operations Before Income Taxes Extraordinary Items Noncontrolling Interest IncomeLossFromContinuingOperationsBeforeIncomeTaxesExtraordinaryItemsNoncontrollingInterest	363700000	usd
CY2023Q3	us-gaap	Income Tax Expense Benefit IncomeTaxExpenseBenefit	77700000	usd
CY2023Q3	us-gaap	Profit Loss ProfitLoss	286000000.0	usd
CY2023Q3	us-gaap	Net Income Loss Attributable To Noncontrolling Interest NetIncomeLossAttributableToNoncontrollingInterest	69000000.0	usd
CY2023Q3	us-gaap	Net Income Loss NetIncomeLoss	217000000.0	usd
CY2023Q3	us-gaap	Weighted Average Number Of Shares Outstanding Basic WeightedAverageNumberOfSharesOutstandingBasic	34900000	shares
CY2023Q3	us-gaap	Weighted Average Number Of Diluted Shares Outstanding WeightedAverageNumberOfDilutedSharesOutstanding	43400000	shares
CY2023Q3	us-gaap	Earnings Per Share Basic EarningsPerShareBasic	6.22
CY2023Q3	us-gaap	Earnings Per Share Diluted EarningsPerShareDiluted	5.48
CY2023Q3	us-gaap	Profit Loss ProfitLoss	286000000.0	usd
CY2023Q3	us-gaap	Other Comprehensive Income Loss Foreign Currency Transaction And Translation Adjustment Net Of Tax OtherComprehensiveIncomeLossForeignCurrencyTransactionAndTranslationAdjustmentNetOfTax	-30600000	usd
CY2023Q3	us-gaap	Other Comprehensive Income Loss Cash Flow Hedge Gain Loss After Reclassification And Tax OtherComprehensiveIncomeLossCashFlowHedgeGainLossAfterReclassificationAndTax	-300000	usd
CY2023Q3	us-gaap	Other Comprehensive Income Loss Available For Sale Securities Adjustment Net Of Tax OtherComprehensiveIncomeLossAvailableForSaleSecuritiesAdjustmentNetOfTax	600000	usd
CY2023Q3	us-gaap	Other Comprehensive Income Loss Net Of Tax OtherComprehensiveIncomeLossNetOfTax	-30300000	usd
CY2023Q3	us-gaap	Comprehensive Income Net Of Tax Including Portion Attributable To Noncontrolling Interest ComprehensiveIncomeNetOfTaxIncludingPortionAttributableToNoncontrollingInterest	255700000	usd
CY2023Q3	us-gaap	Comprehensive Income Net Of Tax Attributable To Noncontrolling Interest ComprehensiveIncomeNetOfTaxAttributableToNoncontrollingInterest	57400000	usd
CY2023Q3	us-gaap	Comprehensive Income Net Of Tax ComprehensiveIncomeNetOfTax	198300000	usd
CY2022Q4	us-gaap	Stockholders Equity Including Portion Attributable To Noncontrolling Interest StockholdersEquityIncludingPortionAttributableToNoncontrollingInterest	4175600000	usd
CY2023Q3	us-gaap	Stockholders Equity Including Portion Attributable To Noncontrolling Interest StockholdersEquityIncludingPortionAttributableToNoncontrollingInterest	4464200000	usd
CY2023Q4	us-gaap	Stockholders Equity Including Portion Attributable To Noncontrolling Interest StockholdersEquityIncludingPortionAttributableToNoncontrollingInterest	4570100000	usd
	us-gaap	Profit Loss ProfitLoss	519500000	usd
	us-gaap	Other Comprehensive Income Loss Net Of Tax OtherComprehensiveIncomeLossNetOfTax	44400000	usd
	us-gaap	Adjustments To Additional Paid In Capital Sharebased Compensation Requisite Service Period Recognition Value AdjustmentsToAdditionalPaidInCapitalSharebasedCompensationRequisiteServicePeriodRecognitionValue	42100000	usd
	us-gaap	Stock Issued During Period Value Share Based Compensation StockIssuedDuringPeriodValueShareBasedCompensation	-77000000.0	usd
	amg	Depreciation And Other Amortization DepreciationAndOtherAmortization	10000000.0	usd
	amg	Depreciation And Other Amortization DepreciationAndOtherAmortization	9400000	usd
	us-gaap	Operating Expenses OperatingExpenses	1112500000	usd
CY2024Q3	us-gaap	Income Loss From Equity Method Investments IncomeLossFromEquityMethodInvestments	52600000	usd
	dei	Entity Central Index Key EntityCentralIndexKey	0001004434
	dei	Amendment Flag AmendmentFlag	false
	dei	Current Fiscal Year End Date CurrentFiscalYearEndDate	--12-31
	dei	Document Fiscal Year Focus DocumentFiscalYearFocus	2024
	dei	Document Fiscal Period Focus DocumentFiscalPeriodFocus	Q3
	dei	Entity Current Reporting Status EntityCurrentReportingStatus	Yes
	dei	Entity Interactive Data Current EntityInteractiveDataCurrent	Yes
	dei	Entity Filer Category EntityFilerCategory	Large Accelerated Filer
	dei	Entity Small Business EntitySmallBusiness	false
	dei	Entity Emerging Growth Company EntityEmergingGrowthCompany	false
	dei	Entity Shell Company EntityShellCompany	false
CY2024Q4	dei	Entity Common Stock Shares Outstanding EntityCommonStockSharesOutstanding	30225132	shares
CY2023Q3	us-gaap	Revenue From Contract With Customer Excluding Assessed Tax RevenueFromContractWithCustomerExcludingAssessedTax	525200000	usd
CY2024Q3	us-gaap	Revenue From Contract With Customer Excluding Assessed Tax RevenueFromContractWithCustomerExcludingAssessedTax	516400000	usd
	us-gaap	Revenue From Contract With Customer Excluding Assessed Tax RevenueFromContractWithCustomerExcludingAssessedTax	1516600000	usd
CY2024Q3	us-gaap	Labor And Related Expense LaborAndRelatedExpense	220800000	usd
	us-gaap	Labor And Related Expense LaborAndRelatedExpense	663000000.0	usd
	us-gaap	Labor And Related Expense LaborAndRelatedExpense	676500000	usd
CY2024Q3	us-gaap	Selling General And Administrative Expense SellingGeneralAndAdministrativeExpense	97000000.0	usd
	us-gaap	Selling General And Administrative Expense SellingGeneralAndAdministrativeExpense	273400000	usd
	us-gaap	Selling General And Administrative Expense SellingGeneralAndAdministrativeExpense	278100000	usd
CY2024Q3	amg	Amortizationand Impairmentsof Intangible Assets AmortizationandImpairmentsofIntangibleAssets	7300000	usd
	amg	Amortizationand Impairmentsof Intangible Assets AmortizationandImpairmentsofIntangibleAssets	37500000	usd
	amg	Amortizationand Impairmentsof Intangible Assets AmortizationandImpairmentsofIntangibleAssets	21800000	usd
CY2023Q3	us-gaap	Interest Expense Operating InterestExpenseOperating	31100000	usd
CY2024Q3	us-gaap	Interest Expense Operating InterestExpenseOperating	34700000	usd
	us-gaap	Interest Expense Operating InterestExpenseOperating	92400000	usd
	us-gaap	Interest Expense Operating InterestExpenseOperating	98100000	usd
CY2024Q3	amg	Depreciation And Other Amortization DepreciationAndOtherAmortization	3300000	usd
CY2024Q3	us-gaap	Other Operating Income Expense Net OtherOperatingIncomeExpenseNet	-11600000	usd
	us-gaap	Other Operating Income Expense Net OtherOperatingIncomeExpenseNet	-36200000	usd
	us-gaap	Other Operating Income Expense Net OtherOperatingIncomeExpenseNet	-31500000	usd
CY2024Q3	us-gaap	Operating Expenses OperatingExpenses	374700000	usd
	us-gaap	Operating Expenses OperatingExpenses	1115400000	usd
	us-gaap	Income Loss From Equity Method Investments IncomeLossFromEquityMethodInvestments	154300000	usd
	us-gaap	Income Loss From Equity Method Investments IncomeLossFromEquityMethodInvestments	188300000	usd
CY2023Q3	us-gaap	Other Investments OtherInvestments	457900000	usd
CY2024Q3	us-gaap	Equity Securities Without Readily Determinable Fair Value Amount EquitySecuritiesWithoutReadilyDeterminableFairValueAmount	50400000	usd
CY2024Q3	us-gaap	Other Investments OtherInvestments	532800000	usd
CY2023Q4	us-gaap	Share Based Compensation Arrangement By Share Based Payment Award Options Outstanding Weighted Average Exercise Price ShareBasedCompensationArrangementByShareBasedPaymentAwardOptionsOutstandingWeightedAverageExercisePrice	76.74
CY2024Q3	us-gaap	Net Income Loss Available To Common Stockholders Basic NetIncomeLossAvailableToCommonStockholdersBasic	123600000	usd
	us-gaap	Net Income Loss Available To Common Stockholders Basic NetIncomeLossAvailableToCommonStockholdersBasic	476800000	usd
	us-gaap	Net Income Loss Available To Common Stockholders Basic NetIncomeLossAvailableToCommonStockholdersBasic	349500000	usd
CY2023Q3	amg	Net Income Loss Other Noncontrolling Interests Redeemable NetIncomeLossOtherNoncontrollingInterestsRedeemable	17100000	usd
CY2024Q3	amg	Net Income Loss Other Noncontrolling Interests Redeemable NetIncomeLossOtherNoncontrollingInterestsRedeemable	5200000	usd
	amg	Net Income Loss Other Noncontrolling Interests Redeemable NetIncomeLossOtherNoncontrollingInterestsRedeemable	39400000	usd
	amg	Net Income Loss Other Noncontrolling Interests Redeemable NetIncomeLossOtherNoncontrollingInterestsRedeemable	1000000.0	usd
CY2023Q3	us-gaap	Interest On Convertible Debt Net Of Tax InterestOnConvertibleDebtNetOfTax	3400000	usd
CY2024Q3	us-gaap	Interest On Convertible Debt Net Of Tax InterestOnConvertibleDebtNetOfTax	3400000	usd
	us-gaap	Interest On Convertible Debt Net Of Tax InterestOnConvertibleDebtNetOfTax	10100000	usd
	us-gaap	Interest On Convertible Debt Net Of Tax InterestOnConvertibleDebtNetOfTax	10100000	usd
CY2023Q3	us-gaap	Net Income Loss Available To Common Stockholders Diluted NetIncomeLossAvailableToCommonStockholdersDiluted	237500000	usd
CY2024Q3	us-gaap	Net Income Loss Available To Common Stockholders Diluted NetIncomeLossAvailableToCommonStockholdersDiluted	132200000	usd
	us-gaap	Net Income Loss Available To Common Stockholders Diluted NetIncomeLossAvailableToCommonStockholdersDiluted	526300000	usd
	us-gaap	Net Income Loss Available To Common Stockholders Diluted NetIncomeLossAvailableToCommonStockholdersDiluted	360600000	usd
	us-gaap	Revenue From Contract With Customer Excluding Assessed Tax RevenueFromContractWithCustomerExcludingAssessedTax	1555200000	usd
CY2024Q3	us-gaap	Gain Loss On Sale Of Business GainLossOnSaleOfBusiness	0	usd
	us-gaap	Gain Loss On Sale Of Business GainLossOnSaleOfBusiness	133100000	usd
	us-gaap	Gain Loss On Sale Of Business GainLossOnSaleOfBusiness	0	usd
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	amg	Investment And Other Income Loss InvestmentAndOtherIncomeLoss	87200000	usd
	amg	Investment And Other Income Loss InvestmentAndOtherIncomeLoss	60000000.0	usd
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	us-gaap	Income Loss From Continuing Operations Before Income Taxes Extraordinary Items Noncontrolling Interest IncomeLossFromContinuingOperationsBeforeIncomeTaxesExtraordinaryItemsNoncontrollingInterest	817300000	usd
	us-gaap	Income Loss From Continuing Operations Before Income Taxes Extraordinary Items Noncontrolling Interest IncomeLossFromContinuingOperationsBeforeIncomeTaxesExtraordinaryItemsNoncontrollingInterest	649500000	usd
CY2024Q3	us-gaap	Income Tax Expense Benefit IncomeTaxExpenseBenefit	31300000	usd
	us-gaap	Income Tax Expense Benefit IncomeTaxExpenseBenefit	155400000	usd
	us-gaap	Income Tax Expense Benefit IncomeTaxExpenseBenefit	130000000.0	usd
CY2023Q3	us-gaap	Weighted Average Number Of Shares Outstanding Basic WeightedAverageNumberOfSharesOutstandingBasic	34900000	shares
CY2024Q3	us-gaap	Weighted Average Number Of Shares Outstanding Basic WeightedAverageNumberOfSharesOutstandingBasic	30100000	shares
	us-gaap	Weighted Average Number Of Shares Outstanding Basic WeightedAverageNumberOfSharesOutstandingBasic	35600000	shares
	us-gaap	Weighted Average Number Of Shares Outstanding Basic WeightedAverageNumberOfSharesOutstandingBasic	31400000	shares
CY2023Q3	us-gaap	Incremental Common Shares Attributable To Share Based Payment Arrangements IncrementalCommonSharesAttributableToShareBasedPaymentArrangements	1700000	shares
CY2024Q3	us-gaap	Incremental Common Shares Attributable To Share Based Payment Arrangements IncrementalCommonSharesAttributableToShareBasedPaymentArrangements	1700000	shares
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	us-gaap	Profit Loss ProfitLoss	661900000	usd
	us-gaap	Profit Loss ProfitLoss	519500000	usd
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	us-gaap	Net Income Loss Attributable To Noncontrolling Interest NetIncomeLossAttributableToNoncontrollingInterest	185100000	usd
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	us-gaap	Net Income Loss NetIncomeLoss	476800000	usd
	us-gaap	Net Income Loss NetIncomeLoss	349500000	usd
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	us-gaap	Earnings Per Share Basic EarningsPerShareBasic	13.41
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	us-gaap	Earnings Per Share Diluted EarningsPerShareDiluted	12.28
	us-gaap	Earnings Per Share Diluted EarningsPerShareDiluted	10.25
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	us-gaap	Profit Loss ProfitLoss	661900000	usd
	us-gaap	Profit Loss ProfitLoss	519500000	usd
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	us-gaap	Other Comprehensive Income Loss Foreign Currency Transaction And Translation Adjustment Net Of Tax OtherComprehensiveIncomeLossForeignCurrencyTransactionAndTranslationAdjustmentNetOfTax	20600000	usd
	us-gaap	Other Comprehensive Income Loss Foreign Currency Transaction And Translation Adjustment Net Of Tax OtherComprehensiveIncomeLossForeignCurrencyTransactionAndTranslationAdjustmentNetOfTax	42600000	usd
CY2024Q3	us-gaap	Other Comprehensive Income Loss Cash Flow Hedge Gain Loss After Reclassification And Tax OtherComprehensiveIncomeLossCashFlowHedgeGainLossAfterReclassificationAndTax	1000000.0	usd
	us-gaap	Other Comprehensive Income Loss Cash Flow Hedge Gain Loss After Reclassification And Tax OtherComprehensiveIncomeLossCashFlowHedgeGainLossAfterReclassificationAndTax	500000	usd
	us-gaap	Other Comprehensive Income Loss Cash Flow Hedge Gain Loss After Reclassification And Tax OtherComprehensiveIncomeLossCashFlowHedgeGainLossAfterReclassificationAndTax	1400000	usd
CY2024Q3	us-gaap	Other Comprehensive Income Loss Available For Sale Securities Adjustment Net Of Tax OtherComprehensiveIncomeLossAvailableForSaleSecuritiesAdjustmentNetOfTax	0.0	usd
	us-gaap	Other Comprehensive Income Loss Available For Sale Securities Adjustment Net Of Tax OtherComprehensiveIncomeLossAvailableForSaleSecuritiesAdjustmentNetOfTax	400000	usd
	us-gaap	Other Comprehensive Income Loss Available For Sale Securities Adjustment Net Of Tax OtherComprehensiveIncomeLossAvailableForSaleSecuritiesAdjustmentNetOfTax	400000	usd
CY2024Q3	us-gaap	Other Comprehensive Income Loss Net Of Tax OtherComprehensiveIncomeLossNetOfTax	40200000	usd
	us-gaap	Other Comprehensive Income Loss Net Of Tax OtherComprehensiveIncomeLossNetOfTax	21500000	usd
	us-gaap	Other Comprehensive Income Loss Net Of Tax OtherComprehensiveIncomeLossNetOfTax	44400000	usd
CY2024Q3	us-gaap	Comprehensive Income Net Of Tax Including Portion Attributable To Noncontrolling Interest ComprehensiveIncomeNetOfTaxIncludingPortionAttributableToNoncontrollingInterest	226000000.0	usd
	us-gaap	Comprehensive Income Net Of Tax Including Portion Attributable To Noncontrolling Interest ComprehensiveIncomeNetOfTaxIncludingPortionAttributableToNoncontrollingInterest	683400000	usd
	us-gaap	Comprehensive Income Net Of Tax Including Portion Attributable To Noncontrolling Interest ComprehensiveIncomeNetOfTaxIncludingPortionAttributableToNoncontrollingInterest	563900000	usd
CY2024Q3	us-gaap	Comprehensive Income Net Of Tax Attributable To Noncontrolling Interest ComprehensiveIncomeNetOfTaxAttributableToNoncontrollingInterest	77900000	usd
	us-gaap	Comprehensive Income Net Of Tax Attributable To Noncontrolling Interest ComprehensiveIncomeNetOfTaxAttributableToNoncontrollingInterest	183100000	usd
	us-gaap	Comprehensive Income Net Of Tax Attributable To Noncontrolling Interest ComprehensiveIncomeNetOfTaxAttributableToNoncontrollingInterest	186000000.0	usd
CY2024Q3	us-gaap	Comprehensive Income Net Of Tax ComprehensiveIncomeNetOfTax	148100000	usd
	us-gaap	Comprehensive Income Net Of Tax ComprehensiveIncomeNetOfTax	500300000	usd
	us-gaap	Comprehensive Income Net Of Tax ComprehensiveIncomeNetOfTax	377900000	usd
CY2023Q4	us-gaap	Cash And Cash Equivalents At Carrying Value CashAndCashEquivalentsAtCarryingValue	813600000	usd
CY2024Q3	us-gaap	Cash And Cash Equivalents At Carrying Value CashAndCashEquivalentsAtCarryingValue	1010700000	usd
CY2023Q4	us-gaap	Accounts Receivable Net AccountsReceivableNet	368400000	usd
CY2024Q3	us-gaap	Accounts Receivable Net AccountsReceivableNet	457100000	usd
CY2023Q4	us-gaap	Marketable Securities MarketableSecurities	461000000.0	usd
CY2024Q3	us-gaap	Marketable Securities MarketableSecurities	66100000	usd
CY2023Q4	us-gaap	Goodwill Goodwill	2523600000	usd
CY2024Q3	us-gaap	Goodwill Goodwill	2532000000	usd
CY2023Q4	us-gaap	Intangible Assets Net Excluding Goodwill IntangibleAssetsNetExcludingGoodwill	1812400000	usd
CY2024Q3	us-gaap	Intangible Assets Net Excluding Goodwill IntangibleAssetsNetExcludingGoodwill	1807100000	usd
CY2023Q4	us-gaap	Investments In Affiliates Subsidiaries Associates And Joint Ventures InvestmentsInAffiliatesSubsidiariesAssociatesAndJointVentures	2288500000	usd
CY2024Q3	us-gaap	Investments In Affiliates Subsidiaries Associates And Joint Ventures InvestmentsInAffiliatesSubsidiariesAssociatesAndJointVentures	2148400000	usd
CY2023Q4	us-gaap	Property Plant And Equipment Net PropertyPlantAndEquipmentNet	67300000	usd
CY2024Q3	us-gaap	Property Plant And Equipment Net PropertyPlantAndEquipmentNet	61000000.0	usd
CY2023Q4	us-gaap	Other Investments OtherInvestments	480900000	usd
CY2024Q3	us-gaap	Other Investments OtherInvestments	532800000	usd
CY2023Q4	us-gaap	Other Assets OtherAssets	243900000	usd
CY2024Q3	us-gaap	Other Assets OtherAssets	287800000	usd
CY2023Q4	us-gaap	Assets Assets	9059600000	usd
CY2024Q3	us-gaap	Assets Assets	8903000000	usd
CY2023Q4	us-gaap	Accounts Payable And Accrued Liabilities Current And Noncurrent AccountsPayableAndAccruedLiabilitiesCurrentAndNoncurrent	628500000	usd
CY2024Q3	us-gaap	Accounts Payable And Accrued Liabilities Current And Noncurrent AccountsPayableAndAccruedLiabilitiesCurrentAndNoncurrent	625700000	usd
CY2023Q4	us-gaap	Long Term Debt LongTermDebt	2537500000	usd
CY2024Q3	us-gaap	Long Term Debt LongTermDebt	2619700000	usd
CY2023Q4	us-gaap	Deferred Income Tax Liabilities Net DeferredIncomeTaxLiabilitiesNet	463800000	usd
CY2024Q3	us-gaap	Deferred Income Tax Liabilities Net DeferredIncomeTaxLiabilitiesNet	522000000.0	usd
CY2023Q4	us-gaap	Other Liabilities OtherLiabilities	466300000	usd
CY2024Q3	us-gaap	Other Liabilities OtherLiabilities	464500000	usd
CY2023Q4	us-gaap	Liabilities Liabilities	4096100000	usd
CY2024Q3	us-gaap	Liabilities Liabilities	4231900000	usd
CY2023Q4	us-gaap	Commitments And Contingencies CommitmentsAndContingencies		usd
CY2024Q3	us-gaap	Commitments And Contingencies CommitmentsAndContingencies		usd
CY2023Q4	us-gaap	Redeemable Noncontrolling Interest Equity Carrying Amount RedeemableNoncontrollingInterestEquityCarryingAmount	393400000	usd
CY2024Q3	us-gaap	Redeemable Noncontrolling Interest Equity Carrying Amount RedeemableNoncontrollingInterestEquityCarryingAmount	397100000	usd
CY2023Q4	us-gaap	Common Stock Par Or Stated Value Per Share CommonStockParOrStatedValuePerShare	0.01
CY2024Q3	us-gaap	Common Stock Par Or Stated Value Per Share CommonStockParOrStatedValuePerShare	0.01
CY2023Q4	us-gaap	Common Stock Shares Authorized CommonStockSharesAuthorized	153000000.0	shares
CY2024Q3	us-gaap	Common Stock Shares Authorized CommonStockSharesAuthorized	153000000.0	shares
CY2024Q3	us-gaap	Common Stock Shares Issued CommonStockSharesIssued	58500000	shares
CY2023Q4	us-gaap	Common Stock Shares Issued CommonStockSharesIssued	58500000	shares
CY2023Q4	us-gaap	Common Stock Value CommonStockValue	600000	usd
CY2024Q3	us-gaap	Common Stock Value CommonStockValue	600000	usd
CY2023Q4	us-gaap	Additional Paid In Capital Common Stock AdditionalPaidInCapitalCommonStock	741400000	usd
CY2024Q3	us-gaap	Additional Paid In Capital Common Stock AdditionalPaidInCapitalCommonStock	711300000	usd
CY2023Q4	amg	Accumulated Other Comprehensive Income Loss Attributable To Parent Net Of Tax AccumulatedOtherComprehensiveIncomeLossAttributableToParentNetOfTax	-167600000	usd
CY2024Q3	amg	Accumulated Other Comprehensive Income Loss Attributable To Parent Net Of Tax AccumulatedOtherComprehensiveIncomeLossAttributableToParentNetOfTax	-139200000	usd
CY2023Q4	us-gaap	Retained Earnings Accumulated Deficit RetainedEarningsAccumulatedDeficit	6389600000	usd
CY2024Q3	us-gaap	Retained Earnings Accumulated Deficit RetainedEarningsAccumulatedDeficit	6738100000	usd
CY2023Q4	us-gaap	Stockholders Equity Before Treasury Stock StockholdersEquityBeforeTreasuryStock	6964000000	usd
CY2024Q3	us-gaap	Stockholders Equity Before Treasury Stock StockholdersEquityBeforeTreasuryStock	7310800000	usd
CY2023Q4	us-gaap	Treasury Stock Common Shares TreasuryStockCommonShares	25300000	shares
CY2024Q3	us-gaap	Treasury Stock Common Shares TreasuryStockCommonShares	28400000	shares
CY2023Q4	us-gaap	Treasury Stock Common Value TreasuryStockCommonValue	3376100000	usd
CY2024Q3	us-gaap	Treasury Stock Common Value TreasuryStockCommonValue	3994500000	usd
CY2023Q4	us-gaap	Stockholders Equity StockholdersEquity	3587900000	usd
CY2024Q3	us-gaap	Stockholders Equity StockholdersEquity	3316300000	usd
CY2023Q4	us-gaap	Other Minority Interests OtherMinorityInterests	982200000	usd
CY2024Q3	us-gaap	Other Minority Interests OtherMinorityInterests	957700000	usd
CY2023Q4	us-gaap	Stockholders Equity Including Portion Attributable To Noncontrolling Interest StockholdersEquityIncludingPortionAttributableToNoncontrollingInterest	4570100000	usd
CY2024Q3	us-gaap	Stockholders Equity Including Portion Attributable To Noncontrolling Interest StockholdersEquityIncludingPortionAttributableToNoncontrollingInterest	4274000000	usd
CY2023Q4	us-gaap	Liabilities And Stockholders Equity LiabilitiesAndStockholdersEquity	9059600000	usd
CY2024Q3	us-gaap	Liabilities And Stockholders Equity LiabilitiesAndStockholdersEquity	8903000000	usd
CY2023Q2	us-gaap	Stockholders Equity Including Portion Attributable To Noncontrolling Interest StockholdersEquityIncludingPortionAttributableToNoncontrollingInterest	4368400000	usd
CY2023Q3	us-gaap	Profit Loss ProfitLoss	286000000.0	usd
CY2023Q3	us-gaap	Other Comprehensive Income Loss Net Of Tax OtherComprehensiveIncomeLossNetOfTax	-30300000	usd
CY2023Q3	us-gaap	Adjustments To Additional Paid In Capital Sharebased Compensation Requisite Service Period Recognition Value AdjustmentsToAdditionalPaidInCapitalSharebasedCompensationRequisiteServicePeriodRecognitionValue	14500000	usd
CY2023Q3	us-gaap	Stock Issued During Period Value Share Based Compensation StockIssuedDuringPeriodValueShareBasedCompensation	-6100000	usd
CY2023Q3	us-gaap	Treasury Stock Value Acquired Cost Method TreasuryStockValueAcquiredCostMethod	173100000	usd
CY2023Q3	us-gaap	Common Stock Dividends Per Share Cash Paid CommonStockDividendsPerShareCashPaid	0.01
CY2023Q3	us-gaap	Dividends Common Stock Cash DividendsCommonStockCash	400000	usd
CY2023Q3	amg	Affiliate Equity Compensation Expense Including Adjustmentsand Portion Attributableto Noncontrolling Interest AffiliateEquityCompensationExpenseIncludingAdjustmentsandPortionAttributabletoNoncontrollingInterest	12500000	usd
CY2023Q3	amg	Noncontrolling Interest Increase Decrease From Subsidiary Equity Issuance NoncontrollingInterestIncreaseDecreaseFromSubsidiaryEquityIssuance	1600000	usd
CY2023Q3	amg	Noncontrolling Interest Increase Decreasefrom Purchaseof Interests NoncontrollingInterestIncreaseDecreasefromPurchaseofInterests	-600000	usd
CY2023Q3	amg	Redeemable Noncontrolling Interest Equity Change In Redemption Value RedeemableNoncontrollingInterestEquityChangeInRedemptionValue	50300000	usd
CY2023Q3	amg	Noncontrolling Interest Increase Decrease From Contributions From Affiliate And Other NoncontrollingInterestIncreaseDecreaseFromContributionsFromAffiliateAndOther	1800000	usd
CY2023Q3	us-gaap	Minority Interest Decrease From Distributions To Noncontrolling Interest Holders MinorityInterestDecreaseFromDistributionsToNoncontrollingInterestHolders	60000000.0	usd
CY2023Q3	us-gaap	Noncontrolling Interest Decrease From Deconsolidation NoncontrollingInterestDecreaseFromDeconsolidation	400000	usd
CY2023Q3	us-gaap	Stockholders Equity Including Portion Attributable To Noncontrolling Interest StockholdersEquityIncludingPortionAttributableToNoncontrollingInterest	4464200000	usd
CY2024Q2	us-gaap	Stockholders Equity Including Portion Attributable To Noncontrolling Interest StockholdersEquityIncludingPortionAttributableToNoncontrollingInterest	4262700000	usd
CY2024Q3	us-gaap	Profit Loss ProfitLoss	185800000	usd
CY2024Q3	us-gaap	Other Comprehensive Income Loss Net Of Tax OtherComprehensiveIncomeLossNetOfTax	40200000	usd
CY2024Q3	us-gaap	Adjustments To Additional Paid In Capital Sharebased Compensation Requisite Service Period Recognition Value AdjustmentsToAdditionalPaidInCapitalSharebasedCompensationRequisiteServicePeriodRecognitionValue	10200000	usd
CY2024Q3	us-gaap	Stock Issued During Period Value Share Based Compensation StockIssuedDuringPeriodValueShareBasedCompensation	-58200000	usd
CY2024Q3	us-gaap	Treasury Stock Value Acquired Cost Method TreasuryStockValueAcquiredCostMethod	103600000	usd
CY2024Q3	us-gaap	Common Stock Dividends Per Share Cash Paid CommonStockDividendsPerShareCashPaid	0.01
CY2024Q3	us-gaap	Dividends Common Stock Cash DividendsCommonStockCash	200000	usd
CY2024Q3	amg	Affiliate Equity Compensation Expense Including Adjustmentsand Portion Attributableto Noncontrolling Interest AffiliateEquityCompensationExpenseIncludingAdjustmentsandPortionAttributabletoNoncontrollingInterest	11300000	usd
CY2024Q3	amg	Noncontrolling Interest Increase Decreasefrom Purchaseof Interests NoncontrollingInterestIncreaseDecreasefromPurchaseofInterests	-1200000	usd
CY2024Q3	amg	Redeemable Noncontrolling Interest Equity Change In Redemption Value RedeemableNoncontrollingInterestEquityChangeInRedemptionValue	-12000000.0	usd
CY2024Q3	amg	Noncontrolling Interest Increase Decrease From Contributions From Affiliate And Other NoncontrollingInterestIncreaseDecreaseFromContributionsFromAffiliateAndOther	-2100000	usd
CY2024Q3	us-gaap	Minority Interest Decrease From Distributions To Noncontrolling Interest Holders MinorityInterestDecreaseFromDistributionsToNoncontrollingInterestHolders	58900000	usd
CY2024Q3	us-gaap	Stockholders Equity Including Portion Attributable To Noncontrolling Interest StockholdersEquityIncludingPortionAttributableToNoncontrollingInterest	4274000000	usd
	us-gaap	Profit Loss ProfitLoss	661900000	usd
	us-gaap	Other Comprehensive Income Loss Net Of Tax OtherComprehensiveIncomeLossNetOfTax	21500000	usd
	us-gaap	Adjustments To Additional Paid In Capital Sharebased Compensation Requisite Service Period Recognition Value AdjustmentsToAdditionalPaidInCapitalSharebasedCompensationRequisiteServicePeriodRecognitionValue	43900000	usd
	us-gaap	Stock Issued During Period Value Share Based Compensation StockIssuedDuringPeriodValueShareBasedCompensation	-31300000	usd
	us-gaap	Treasury Stock Value Acquired Cost Method TreasuryStockValueAcquiredCostMethod	218000000.0	usd
	us-gaap	Common Stock Dividends Per Share Cash Paid CommonStockDividendsPerShareCashPaid	0.03
	us-gaap	Dividends Common Stock Cash DividendsCommonStockCash	1200000	usd
	amg	Affiliate Equity Compensation Expense Including Adjustmentsand Portion Attributableto Noncontrolling Interest AffiliateEquityCompensationExpenseIncludingAdjustmentsandPortionAttributabletoNoncontrollingInterest	41100000	usd
	amg	Noncontrolling Interest Increase Decrease From Subsidiary Equity Issuance NoncontrollingInterestIncreaseDecreaseFromSubsidiaryEquityIssuance	16300000	usd
	amg	Noncontrolling Interest Increase Decreasefrom Purchaseof Interests NoncontrollingInterestIncreaseDecreasefromPurchaseofInterests	3800000	usd
	amg	Redeemable Noncontrolling Interest Equity Change In Redemption Value RedeemableNoncontrollingInterestEquityChangeInRedemptionValue	-46900000	usd
	amg	Noncontrolling Interest Decreasefrom Transfersto Noncontrolling Interest Holders NoncontrollingInterestDecreasefromTransferstoNoncontrollingInterestHolders	100000	usd
	amg	Noncontrolling Interest Increase Decrease From Contributions From Affiliate And Other NoncontrollingInterestIncreaseDecreaseFromContributionsFromAffiliateAndOther	14400000	usd
	us-gaap	Minority Interest Decrease From Distributions To Noncontrolling Interest Holders MinorityInterestDecreaseFromDistributionsToNoncontrollingInterestHolders	216400000	usd
	us-gaap	Noncontrolling Interest Decrease From Deconsolidation NoncontrollingInterestDecreaseFromDeconsolidation	400000	usd
	us-gaap	Treasury Stock Value Acquired Cost Method TreasuryStockValueAcquiredCostMethod	584900000	usd
	us-gaap	Common Stock Dividends Per Share Cash Paid CommonStockDividendsPerShareCashPaid	0.03
	us-gaap	Dividends Common Stock Cash DividendsCommonStockCash	1000000.0	usd
	amg	Affiliate Equity Compensation Expense Including Adjustmentsand Portion Attributableto Noncontrolling Interest AffiliateEquityCompensationExpenseIncludingAdjustmentsandPortionAttributabletoNoncontrollingInterest	42600000	usd
	amg	Noncontrolling Interest Increase Decrease From Subsidiary Equity Issuance NoncontrollingInterestIncreaseDecreaseFromSubsidiaryEquityIssuance	7500000	usd
	amg	Noncontrolling Interest Increase Decreasefrom Purchaseof Interests NoncontrollingInterestIncreaseDecreasefromPurchaseofInterests	-14800000	usd
	amg	Redeemable Noncontrolling Interest Equity Change In Redemption Value RedeemableNoncontrollingInterestEquityChangeInRedemptionValue	-42700000	usd
	amg	Noncontrolling Interest Decreasefrom Transfersto Noncontrolling Interest Holders NoncontrollingInterestDecreasefromTransferstoNoncontrollingInterestHolders	1700000	usd
	amg	Noncontrolling Interest Increase Decrease From Contributions From Affiliate And Other NoncontrollingInterestIncreaseDecreaseFromContributionsFromAffiliateAndOther	-23600000	usd
	us-gaap	Minority Interest Decrease From Distributions To Noncontrolling Interest Holders MinorityInterestDecreaseFromDistributionsToNoncontrollingInterestHolders	206500000	usd
CY2024Q3	us-gaap	Stockholders Equity Including Portion Attributable To Noncontrolling Interest StockholdersEquityIncludingPortionAttributableToNoncontrollingInterest	4274000000	usd
	us-gaap	Profit Loss ProfitLoss	519500000	usd
	amg	Amortizationand Impairmentsof Intangible Assets AmortizationandImpairmentsofIntangibleAssets	21800000	usd
	amg	Depreciation And Other Amortization DepreciationAndOtherAmortization	9400000	usd
	us-gaap	Deferred Income Tax Expense Benefit DeferredIncomeTaxExpenseBenefit	59500000	usd
	us-gaap	Income Loss From Equity Method Investments IncomeLossFromEquityMethodInvestments	188300000	usd
	us-gaap	Gain Loss On Sale Of Business GainLossOnSaleOfBusiness	133100000	usd
	us-gaap	Gain Loss On Sale Of Business GainLossOnSaleOfBusiness	0	usd
	us-gaap	Equity Method Investment Dividends Or Distributions EquityMethodInvestmentDividendsOrDistributions	421700000	usd
	us-gaap	Equity Method Investment Dividends Or Distributions EquityMethodInvestmentDividendsOrDistributions	357300000	usd
	us-gaap	Share Based Compensation ShareBasedCompensation	83400000	usd
	us-gaap	Share Based Compensation ShareBasedCompensation	88600000	usd
	us-gaap	Gain Loss On Investments GainLossOnInvestments	68700000	usd
	us-gaap	Gain Loss On Investments GainLossOnInvestments	30700000	usd
	us-gaap	Other Noncash Income Expense OtherNoncashIncomeExpense	3700000	usd
	us-gaap	Other Noncash Income Expense OtherNoncashIncomeExpense	3800000	usd
	amg	Purchasesof Securitiesby Affiliate Sponsored Consolidated Products PurchasesofSecuritiesbyAffiliateSponsoredConsolidatedProducts	32600000	usd
	amg	Purchasesof Securitiesby Affiliate Sponsored Consolidated Products PurchasesofSecuritiesbyAffiliateSponsoredConsolidatedProducts	61800000	usd
	amg	Saleof Securitiesby Affiliate Sponsored Consolidated Products SaleofSecuritiesbyAffiliateSponsoredConsolidatedProducts	38900000	usd
	amg	Saleof Securitiesby Affiliate Sponsored Consolidated Products SaleofSecuritiesbyAffiliateSponsoredConsolidatedProducts	48100000	usd
	us-gaap	Increase Decrease In Receivables IncreaseDecreaseInReceivables	116400000	usd
	us-gaap	Increase Decrease In Receivables IncreaseDecreaseInReceivables	76500000	usd
	us-gaap	Increase Decrease In Other Operating Assets IncreaseDecreaseInOtherOperatingAssets	-23300000	usd
	us-gaap	Increase Decrease In Other Operating Assets IncreaseDecreaseInOtherOperatingAssets	-13800000	usd
	us-gaap	Increase Decrease In Operating Liabilities IncreaseDecreaseInOperatingLiabilities	-161500000	usd
	us-gaap	Increase Decrease In Operating Liabilities IncreaseDecreaseInOperatingLiabilities	-37300000	usd
	us-gaap	Net Cash Provided By Used In Operating Activities NetCashProvidedByUsedInOperatingActivities	619400000	usd
	us-gaap	Net Cash Provided By Used In Operating Activities NetCashProvidedByUsedInOperatingActivities	719600000	usd
	us-gaap	Payments To Acquire Interest In Subsidiaries And Affiliates PaymentsToAcquireInterestInSubsidiariesAndAffiliates	93800000	usd
	us-gaap	Payments To Acquire Interest In Subsidiaries And Affiliates PaymentsToAcquireInterestInSubsidiariesAndAffiliates	5900000	usd
	us-gaap	Proceeds From Divestiture Of Interest In Subsidiaries And Affiliates ProceedsFromDivestitureOfInterestInSubsidiariesAndAffiliates	294000000.0	usd
	us-gaap	Proceeds From Divestiture Of Interest In Subsidiaries And Affiliates ProceedsFromDivestitureOfInterestInSubsidiariesAndAffiliates	0	usd
	us-gaap	Payments To Acquire Property Plant And Equipment PaymentsToAcquirePropertyPlantAndEquipment	6600000	usd
	us-gaap	Payments To Acquire Property Plant And Equipment PaymentsToAcquirePropertyPlantAndEquipment	2300000	usd
	us-gaap	Payments To Acquire Marketable Securities PaymentsToAcquireMarketableSecurities	477600000	usd
	us-gaap	Payments To Acquire Marketable Securities PaymentsToAcquireMarketableSecurities	496400000	usd
	us-gaap	Proceeds From Sale Maturity And Collections Of Investments ProceedsFromSaleMaturityAndCollectionsOfInvestments	761900000	usd
	us-gaap	Proceeds From Sale Maturity And Collections Of Investments ProceedsFromSaleMaturityAndCollectionsOfInvestments	875200000	usd
	us-gaap	Net Cash Provided By Used In Investing Activities NetCashProvidedByUsedInInvestingActivities	477900000	usd
	us-gaap	Net Cash Provided By Used In Investing Activities NetCashProvidedByUsedInInvestingActivities	370600000	usd
	us-gaap	Proceeds From Issuance Of Long Term Debt ProceedsFromIssuanceOfLongTermDebt	25000000.0	usd
	us-gaap	Proceeds From Issuance Of Long Term Debt ProceedsFromIssuanceOfLongTermDebt	847600000	usd
	us-gaap	Repayments Of Long Term Debt RepaymentsOfLongTermDebt	25000000.0	usd
	us-gaap	Repayments Of Long Term Debt RepaymentsOfLongTermDebt	750000000.0	usd
	us-gaap	Payments For Repurchase Of Common Stock PaymentsForRepurchaseOfCommonStock	213600000	usd
	us-gaap	Payments For Repurchase Of Common Stock PaymentsForRepurchaseOfCommonStock	589500000	usd
	us-gaap	Payments Of Dividends Common Stock PaymentsOfDividendsCommonStock	1200000	usd
	us-gaap	Payments Of Dividends Common Stock PaymentsOfDividendsCommonStock	1000000.0	usd
	us-gaap	Payments Of Dividends Minority Interest PaymentsOfDividendsMinorityInterest	216400000	usd
	us-gaap	Payments Of Dividends Minority Interest PaymentsOfDividendsMinorityInterest	206500000	usd
	amg	Proceeds From Payments For Affiliate Equity Issuances And Repurchases ProceedsFromPaymentsForAffiliateEquityIssuancesAndRepurchases	-28300000	usd
	amg	Proceeds From Payments For Affiliate Equity Issuances And Repurchases ProceedsFromPaymentsForAffiliateEquityIssuancesAndRepurchases	-54100000	usd
	amg	Subscriptions To Consolidated Affiliate Sponsored Investment Products Net Of Redemptions SubscriptionsToConsolidatedAffiliateSponsoredInvestmentProductsNetOfRedemptions	-9700000	usd
	amg	Subscriptions To Consolidated Affiliate Sponsored Investment Products Net Of Redemptions SubscriptionsToConsolidatedAffiliateSponsoredInvestmentProductsNetOfRedemptions	-6300000	usd
	us-gaap	Proceeds From Payments For Other Financing Activities ProceedsFromPaymentsForOtherFinancingActivities	-54800000	usd
	us-gaap	Proceeds From Payments For Other Financing Activities ProceedsFromPaymentsForOtherFinancingActivities	-144300000	usd
	us-gaap	Net Cash Provided By Used In Financing Activities NetCashProvidedByUsedInFinancingActivities	-524000000.0	usd
	us-gaap	Net Cash Provided By Used In Financing Activities NetCashProvidedByUsedInFinancingActivities	-904100000	usd
	us-gaap	Effect Of Exchange Rate On Cash Cash Equivalents Restricted Cash And Restricted Cash Equivalents EffectOfExchangeRateOnCashCashEquivalentsRestrictedCashAndRestrictedCashEquivalents	-200000	usd
	us-gaap	Effect Of Exchange Rate On Cash Cash Equivalents Restricted Cash And Restricted Cash Equivalents EffectOfExchangeRateOnCashCashEquivalentsRestrictedCashAndRestrictedCashEquivalents	5700000	usd
	us-gaap	Cash Cash Equivalents Restricted Cash And Restricted Cash Equivalents Period Increase Decrease Including Exchange Rate Effect CashCashEquivalentsRestrictedCashAndRestrictedCashEquivalentsPeriodIncreaseDecreaseIncludingExchangeRateEffect	573100000	usd
	us-gaap	Cash Cash Equivalents Restricted Cash And Restricted Cash Equivalents Period Increase Decrease Including Exchange Rate Effect CashCashEquivalentsRestrictedCashAndRestrictedCashEquivalentsPeriodIncreaseDecreaseIncludingExchangeRateEffect	191800000	usd
CY2022Q4	us-gaap	Cash Cash Equivalents Restricted Cash And Restricted Cash Equivalents CashCashEquivalentsRestrictedCashAndRestrictedCashEquivalents	429200000	usd
CY2023Q3	amg	Reduction To Cash Due To Deconsolidation Affiliates And Affiliate Sponsored Investment Products ReductionToCashDueToDeconsolidationAffiliatesAndAffiliateSponsoredInvestmentProducts	3100000	usd
CY2024Q3	amg	Reduction To Cash Due To Deconsolidation Affiliates And Affiliate Sponsored Investment Products ReductionToCashDueToDeconsolidationAffiliatesAndAffiliateSponsoredInvestmentProducts	-5300000	usd
CY2023Q3	us-gaap	Cash Cash Equivalents Restricted Cash And Restricted Cash Equivalents CashCashEquivalentsRestrictedCashAndRestrictedCashEquivalents	999200000	usd
CY2024Q3	us-gaap	Cash Cash Equivalents Restricted Cash And Restricted Cash Equivalents CashCashEquivalentsRestrictedCashAndRestrictedCashEquivalents	1010700000	usd
	us-gaap	Use Of Estimates UseOfEstimates	<span style="font-family: Times New Roman, sans-serif; font-size: 10pt; font-style: normal; font-weight: normal; left: 67.5pt; position: var(--position); text-decoration: none; white-space: pre;">The preparation of financial statements in conformity with GAAP requires management to make estimates and assumptions <span style="display: inline-block; height: 6.93pt;"></span></span>that affect the reported amounts and disclosures in the financial statements. Actual results could differ from those estimates.
CY2023Q4	us-gaap	Equity Securities Fv Ni Cost EquitySecuritiesFvNiCost	35300000	usd
CY2024Q3	us-gaap	Equity Securities Fv Ni Cost EquitySecuritiesFvNiCost	37600000	usd
CY2023	us-gaap	Equity Securities Fv Ni Unrealized Gain EquitySecuritiesFvNiUnrealizedGain	2600000	usd
	us-gaap	Equity Securities Fv Ni Unrealized Gain EquitySecuritiesFvNiUnrealizedGain	4700000	usd
CY2023	us-gaap	Equity Securities Fv Ni Unrealized Loss EquitySecuritiesFvNiUnrealizedLoss	0.0	usd
	us-gaap	Equity Securities Fv Ni Unrealized Loss EquitySecuritiesFvNiUnrealizedLoss	300000	usd
CY2023Q4	us-gaap	Equity Securities Fv Ni Current And Noncurrent EquitySecuritiesFvNiCurrentAndNoncurrent	37900000	usd
CY2024Q3	us-gaap	Equity Securities Fv Ni Current And Noncurrent EquitySecuritiesFvNiCurrentAndNoncurrent	42000000.0	usd
CY2023Q3	us-gaap	Equity Securities Fv Ni Unrealized Gain Loss EquitySecuritiesFvNiUnrealizedGainLoss	-2100000	usd
CY2023Q4	us-gaap	Available For Sale Debt Securities Amortized Cost Basis AvailableForSaleDebtSecuritiesAmortizedCostBasis	405400000	usd
CY2024Q3	us-gaap	Available For Sale Debt Securities Amortized Cost Basis AvailableForSaleDebtSecuritiesAmortizedCostBasis	0	usd
CY2023Q4	us-gaap	Trading Securities Debt Amortized Cost TradingSecuritiesDebtAmortizedCost	17900000	usd
CY2024Q3	us-gaap	Trading Securities Debt Amortized Cost TradingSecuritiesDebtAmortizedCost	23300000	usd
CY2023Q4	us-gaap	Available For Sale Debt Securities Accumulated Gross Unrealized Gain Before Tax AvailableForSaleDebtSecuritiesAccumulatedGrossUnrealizedGainBeforeTax	0.0	usd
CY2024Q3	us-gaap	Available For Sale Debt Securities Accumulated Gross Unrealized Gain Before Tax AvailableForSaleDebtSecuritiesAccumulatedGrossUnrealizedGainBeforeTax	0	usd
CY2023Q4	amg	Debt Securities Trading Accumulated Gross Unrealized Gain Before Tax DebtSecuritiesTradingAccumulatedGrossUnrealizedGainBeforeTax	0	usd
CY2024Q3	amg	Debt Securities Trading Accumulated Gross Unrealized Gain Before Tax DebtSecuritiesTradingAccumulatedGrossUnrealizedGainBeforeTax	800000	usd
CY2023Q4	us-gaap	Available For Sale Debt Securities Accumulated Gross Unrealized Loss Before Tax AvailableForSaleDebtSecuritiesAccumulatedGrossUnrealizedLossBeforeTax	100000	usd
CY2024Q3	us-gaap	Available For Sale Debt Securities Accumulated Gross Unrealized Loss Before Tax AvailableForSaleDebtSecuritiesAccumulatedGrossUnrealizedLossBeforeTax	0	usd
CY2023Q4	amg	Debt Securities Trading Accumulated Gross Unrealized Loss Before Tax DebtSecuritiesTradingAccumulatedGrossUnrealizedLossBeforeTax	100000	usd
CY2024Q3	amg	Debt Securities Trading Accumulated Gross Unrealized Loss Before Tax DebtSecuritiesTradingAccumulatedGrossUnrealizedLossBeforeTax	0	usd
CY2023Q4	us-gaap	Available For Sale Securities Debt Securities AvailableForSaleSecuritiesDebtSecurities	405300000	usd
CY2024Q3	us-gaap	Available For Sale Securities Debt Securities AvailableForSaleSecuritiesDebtSecurities	0	usd
CY2023Q4	us-gaap	Trading Securities Debt TradingSecuritiesDebt	17800000	usd
CY2024Q3	us-gaap	Trading Securities Debt TradingSecuritiesDebt	24100000	usd
CY2023Q3	us-gaap	Payments To Acquire Available For Sale Securities Debt PaymentsToAcquireAvailableForSaleSecuritiesDebt	245300000	usd
	us-gaap	Payments To Acquire Available For Sale Securities Debt PaymentsToAcquireAvailableForSaleSecuritiesDebt	420300000	usd
CY2024Q3	us-gaap	Proceeds From Maturities Prepayments And Calls Of Available For Sale Securities ProceedsFromMaturitiesPrepaymentsAndCallsOfAvailableForSaleSecurities	100000000.0	usd
CY2024Q3	us-gaap	Payments To Acquire Available For Sale Securities Debt PaymentsToAcquireAvailableForSaleSecuritiesDebt	0	usd
	us-gaap	Proceeds From Maturities Prepayments And Calls Of Available For Sale Securities ProceedsFromMaturitiesPrepaymentsAndCallsOfAvailableForSaleSecurities	825200000	usd
	us-gaap	Payments To Acquire Available For Sale Securities Debt PaymentsToAcquireAvailableForSaleSecuritiesDebt	413900000	usd
CY2023Q3	us-gaap	Debt Securities Trading Unrealized Gain Loss DebtSecuritiesTradingUnrealizedGainLoss	0	usd
	us-gaap	Debt Securities Trading Unrealized Gain Loss DebtSecuritiesTradingUnrealizedGainLoss	0	usd
CY2024Q3	us-gaap	Debt Securities Trading Unrealized Gain Loss DebtSecuritiesTradingUnrealizedGainLoss	800000	usd
	us-gaap	Debt Securities Trading Unrealized Gain Loss DebtSecuritiesTradingUnrealizedGainLoss	1400000	usd
CY2023Q4	us-gaap	Fair Value Investments Entities That Calculate Net Asset Value Per Share Unfunded Committments FairValueInvestmentsEntitiesThatCalculateNetAssetValuePerShareUnfundedCommittments	187200000	usd
CY2024Q3	us-gaap	Fair Value Investments Entities That Calculate Net Asset Value Per Share Unfunded Committments FairValueInvestmentsEntitiesThatCalculateNetAssetValuePerShareUnfundedCommittments	215700000	usd
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CY2024Q3	amg	Equity Securities Without Readily Determinable Fair Value Cost EquitySecuritiesWithoutReadilyDeterminableFairValueCost	8500000	usd
CY2023Q4	us-gaap	Equity Securities Without Readily Determinable Fair Value Upward Price Adjustment Cumulative Amount EquitySecuritiesWithoutReadilyDeterminableFairValueUpwardPriceAdjustmentCumulativeAmount	41900000	usd
CY2024Q3	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
CY2024Q3	us-gaap	Equity Securities Without Readily Determinable Fair Value Amount EquitySecuritiesWithoutReadilyDeterminableFairValueAmount	50400000	usd
	us-gaap	Equity Securities Without Readily Determinable Fair Value Downward Price Adjustment Annual Amount EquitySecuritiesWithoutReadilyDeterminableFairValueDownwardPriceAdjustmentAnnualAmount	0	usd
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CY2024Q3	us-gaap	Equity Securities Without Readily Determinable Fair Value Upward Price Adjustment Annual Amount EquitySecuritiesWithoutReadilyDeterminableFairValueUpwardPriceAdjustmentAnnualAmount	0	usd
CY2024Q3	us-gaap	Equity Securities Without Readily Determinable Fair Value Downward Price Adjustment Annual Amount EquitySecuritiesWithoutReadilyDeterminableFairValueDownwardPriceAdjustmentAnnualAmount	0	usd
CY2023Q2	us-gaap	Equity Securities Without Readily Determinable Fair Value Amount EquitySecuritiesWithoutReadilyDeterminableFairValueAmount	50400000	usd
CY2023Q2	us-gaap	Other Investments OtherInvestments	457000000.0	usd
CY2024Q2	us-gaap	Equity Securities Without Readily Determinable Fair Value Amount EquitySecuritiesWithoutReadilyDeterminableFairValueAmount	50400000	usd
CY2024Q2	us-gaap	Other Investments OtherInvestments	530300000	usd
CY2023Q3	amg	Equity Securities Without Readily Determinable Fair Value Purchases And Commitments EquitySecuritiesWithoutReadilyDeterminableFairValuePurchasesAndCommitments	0	usd
CY2023Q3	amg	Other Investments Purchases OtherInvestmentsPurchases	16000000.0	usd
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CY2024Q3	amg	Other Investments Purchases OtherInvestmentsPurchases	13600000	usd
CY2023Q3	amg	Equity Securities Without Readily Determinable Fair Value Sales And Distributions EquitySecuritiesWithoutReadilyDeterminableFairValueSalesAndDistributions	0	usd
CY2023Q3	amg	Other Investments Sales OtherInvestmentsSales	20500000	usd
CY2024Q3	amg	Equity Securities Without Readily Determinable Fair Value Sales And Distributions EquitySecuritiesWithoutReadilyDeterminableFairValueSalesAndDistributions	0	usd
CY2024Q3	amg	Other Investments Sales OtherInvestmentsSales	20400000	usd
CY2023Q3	amg	Equity Securities Without Readily Determinable Fair Value Net Gain Loss EquitySecuritiesWithoutReadilyDeterminableFairValueNetGainLoss	0	usd
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CY2024Q3	amg	Other Investments Gain Loss Net OtherInvestmentsGainLossNet	9300000	usd
CY2023Q3	us-gaap	Equity Securities Without Readily Determinable Fair Value Amount EquitySecuritiesWithoutReadilyDeterminableFairValueAmount	50400000	usd
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CY2022Q4	us-gaap	Other Investments OtherInvestments	421600000	usd
CY2023Q4	us-gaap	Equity Securities Without Readily Determinable Fair Value Amount EquitySecuritiesWithoutReadilyDeterminableFairValueAmount	50400000	usd
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	amg	Equity Securities Without Readily Determinable Fair Value Purchases And Commitments EquitySecuritiesWithoutReadilyDeterminableFairValuePurchasesAndCommitments	0	usd
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	amg	Equity Securities Without Readily Determinable Fair Value Net Gain Loss EquitySecuritiesWithoutReadilyDeterminableFairValueNetGainLoss	0	usd
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CY2023Q3	us-gaap	Equity Securities Without Readily Determinable Fair Value Amount EquitySecuritiesWithoutReadilyDeterminableFairValueAmount	50400000	usd
CY2023Q3	us-gaap	Other Investments OtherInvestments	457900000	usd
CY2024Q3	us-gaap	Equity Securities Without Readily Determinable Fair Value Amount EquitySecuritiesWithoutReadilyDeterminableFairValueAmount	50400000	usd
CY2024Q3	us-gaap	Other Investments OtherInvestments	532800000	usd
CY2023Q4	us-gaap	Investments In Affiliates Subsidiaries Associates And Joint Ventures InvestmentsInAffiliatesSubsidiariesAssociatesAndJointVentures	2288500000	usd
CY2024Q3	us-gaap	Investments In Affiliates Subsidiaries Associates And Joint Ventures InvestmentsInAffiliatesSubsidiariesAssociatesAndJointVentures	2148400000	usd
CY2023Q4	us-gaap	Equity Method Investments EquityMethodInvestments	90300000	usd
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CY2023Q4	us-gaap	Long Term Debt LongTermDebt	2537500000	usd
CY2024Q3	us-gaap	Long Term Debt LongTermDebt	2619700000	usd
CY2024Q3	amg	Investment Commitment Amount InvestmentCommitmentAmount	215700000	usd
CY2024Q3	amg	Deferred Payment Obligations Liability DeferredPaymentObligationsLiability	43300000	usd
CY2024Q3	amg	Deferred Payment Obligations Liability To Be Paid Remainder Of Fiscal Year DeferredPaymentObligationsLiabilityToBePaidRemainderOfFiscalYear	21700000	usd
CY2024Q3	amg	Deferred Payment Obligations Liability To Be Paid Year One DeferredPaymentObligationsLiabilityToBePaidYearOne	21600000	usd
CY2024Q3	amg	Contingent Consideration Liability ContingentConsiderationLiability	6500000	usd
CY2024Q3	amg	Contingent Consideration Liability To Be Paid Remainder Of Fiscal Year ContingentConsiderationLiabilityToBePaidRemainderOfFiscalYear	0	usd
CY2024Q3	amg	Contingent Consideration Liability To Be Paid Year One ContingentConsiderationLiabilityToBePaidYearOne	6500000	usd
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	us-gaap	Goodwill Foreign Currency Translation Gain Loss GoodwillForeignCurrencyTranslationGainLoss	8400000	usd
CY2024Q3	us-gaap	Goodwill Goodwill	2532000000	usd
	us-gaap	Goodwill Impairment Loss GoodwillImpairmentLoss	0	usd
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
CY2024Q3	amg	Number Of Affiliates Equity Method Investment NumberOfAffiliatesEquityMethodInvestment	22	affiliate
CY2023Q4	amg	Number Of Affiliates Equity Method Investment NumberOfAffiliatesEquityMethodInvestment	22	affiliate
CY2024Q3	amg	Common Stock Voting Rights Percent CommonStockVotingRightsPercent	0.05
CY2023Q3	us-gaap	Allocated Share Based Compensation Expense AllocatedShareBasedCompensationExpense	14500000	usd
CY2024Q3	us-gaap	Allocated Share Based Compensation Expense AllocatedShareBasedCompensationExpense	10200000	usd
	us-gaap	Allocated Share Based Compensation Expense AllocatedShareBasedCompensationExpense	43900000	usd
	us-gaap	Allocated Share Based Compensation Expense AllocatedShareBasedCompensationExpense	42100000	usd
CY2023Q3	us-gaap	Employee Service Share Based Compensation Tax Benefit From Compensation Expense EmployeeServiceShareBasedCompensationTaxBenefitFromCompensationExpense	1900000	usd
CY2024Q3	us-gaap	Employee Service Share Based Compensation Tax Benefit From Compensation Expense EmployeeServiceShareBasedCompensationTaxBenefitFromCompensationExpense	1200000	usd
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	us-gaap	Employee Service Share Based Compensation Tax Benefit From Compensation Expense EmployeeServiceShareBasedCompensationTaxBenefitFromCompensationExpense	5200000	usd
CY2023Q4	us-gaap	Employee Service Share Based Compensation Nonvested Awards Total Compensation Cost Not Yet Recognized EmployeeServiceShareBasedCompensationNonvestedAwardsTotalCompensationCostNotYetRecognized	54400000	usd
CY2024Q3	us-gaap	Employee Service Share Based Compensation Nonvested Awards Total Compensation Cost Not Yet Recognized EmployeeServiceShareBasedCompensationNonvestedAwardsTotalCompensationCostNotYetRecognized	48700000	usd
	us-gaap	Employee Service Share Based Compensation Nonvested Awards Total Compensation Cost Not Yet Recognized Period For Recognition1 EmployeeServiceShareBasedCompensationNonvestedAwardsTotalCompensationCostNotYetRecognizedPeriodForRecognition1	P2Y
CY2023Q4	us-gaap	Share Based Compensation Arrangement By Share Based Payment Award Options Outstanding Number ShareBasedCompensationArrangementByShareBasedPaymentAwardOptionsOutstandingNumber	3200000	shares
	us-gaap	Share Based Compensation Arrangement By Share Based Payment Award Options Grants In Period Gross ShareBasedCompensationArrangementByShareBasedPaymentAwardOptionsGrantsInPeriodGross	0	shares
	us-gaap	Share Based Compensation Arrangements By Share Based Payment Award Options Grants In Period Weighted Average Exercise Price ShareBasedCompensationArrangementsByShareBasedPaymentAwardOptionsGrantsInPeriodWeightedAverageExercisePrice	0
	us-gaap	Stock Issued During Period Shares Stock Options Exercised StockIssuedDuringPeriodSharesStockOptionsExercised	1300000	shares
	us-gaap	Share Based Compensation Arrangements By Share Based Payment Award Options Exercises In Period Weighted Average Exercise Price ShareBasedCompensationArrangementsByShareBasedPaymentAwardOptionsExercisesInPeriodWeightedAverageExercisePrice	74.82
	us-gaap	Share Based Compensation Arrangement By Share Based Payment Award Options Forfeitures In Period ShareBasedCompensationArrangementByShareBasedPaymentAwardOptionsForfeituresInPeriod	0.0	shares
	us-gaap	Share Based Compensation Arrangements By Share Based Payment Award Options Forfeitures In Period Weighted Average Exercise Price ShareBasedCompensationArrangementsByShareBasedPaymentAwardOptionsForfeituresInPeriodWeightedAverageExercisePrice	185.98
	us-gaap	Share Based Compensation Arrangement By Share Based Payment Award Options Expirations In Period ShareBasedCompensationArrangementByShareBasedPaymentAwardOptionsExpirationsInPeriod	0.0	shares
	us-gaap	Share Based Compensation Arrangements By Share Based Payment Award Options Expirations In Period Weighted Average Exercise Price ShareBasedCompensationArrangementsByShareBasedPaymentAwardOptionsExpirationsInPeriodWeightedAverageExercisePrice	152.36
	amg	Share Based Compensation Arrangement By Sharebased Payment Award Options Period Increase Decrease Performance Condition Changes ShareBasedCompensationArrangementBySharebasedPaymentAwardOptionsPeriodIncreaseDecreasePerformanceConditionChanges	0.0	shares
	amg	Sharebased Compensation Arrangementsby Sharebased Payment Award Options Performance Condition Changes Weighted Average Exercise Price SharebasedCompensationArrangementsbySharebasedPaymentAwardOptionsPerformanceConditionChangesWeightedAverageExercisePrice	129.17
CY2024Q3	us-gaap	Share Based Compensation Arrangement By Share Based Payment Award Options Outstanding Number ShareBasedCompensationArrangementByShareBasedPaymentAwardOptionsOutstandingNumber	1900000	shares
CY2024Q3	us-gaap	Share Based Compensation Arrangement By Share Based Payment Award Options Outstanding Weighted Average Exercise Price ShareBasedCompensationArrangementByShareBasedPaymentAwardOptionsOutstandingWeightedAverageExercisePrice	78.02
	us-gaap	Sharebased Compensation Arrangement By Sharebased Payment Award Options Outstanding Weighted Average Remaining Contractual Term2 SharebasedCompensationArrangementBySharebasedPaymentAwardOptionsOutstandingWeightedAverageRemainingContractualTerm2	P2Y1M6D
CY2024Q3	us-gaap	Share Based Compensation Arrangement By Share Based Payment Award Options Exercisable Number ShareBasedCompensationArrangementByShareBasedPaymentAwardOptionsExercisableNumber	1500000	shares
CY2024Q3	us-gaap	Share Based Compensation Arrangement By Share Based Payment Award Options Exercisable Weighted Average Exercise Price ShareBasedCompensationArrangementByShareBasedPaymentAwardOptionsExercisableWeightedAverageExercisePrice	75.89
	us-gaap	Sharebased Compensation Arrangement By Sharebased Payment Award Options Exercisable Weighted Average Remaining Contractual Term1 SharebasedCompensationArrangementBySharebasedPaymentAwardOptionsExercisableWeightedAverageRemainingContractualTerm1	P1Y10M24D
	us-gaap	Sharebased Compensation Arrangement By Sharebased Payment Award Options Vested In Period Fair Value1 SharebasedCompensationArrangementBySharebasedPaymentAwardOptionsVestedInPeriodFairValue1	0	usd
	us-gaap	Sharebased Compensation Arrangement By Sharebased Payment Award Options Vested In Period Fair Value1 SharebasedCompensationArrangementBySharebasedPaymentAwardOptionsVestedInPeriodFairValue1	0	usd
CY2023Q4	us-gaap	Redeemable Noncontrolling Interest Equity Carrying Amount RedeemableNoncontrollingInterestEquityCarryingAmount	393400000	usd
	amg	Noncontrolling Interest Increasedecrease Attributableto Consolidated Partnerships NoncontrollingInterestIncreasedecreaseAttributabletoConsolidatedPartnerships	1500000	usd
	amg	Noncontrolling Interest Decreasefrom Transfersto Other Liabilities NoncontrollingInterestDecreasefromTransferstoOtherLiabilities	42200000	usd
	amg	Noncontrolling Interest Increase From Transfers To Noncontrolling Interest Holders NoncontrollingInterestIncreaseFromTransfersToNoncontrollingInterestHolders	1700000	usd
	amg	Redeemable Noncontrolling Interest Equity Change In Redemption Value RedeemableNoncontrollingInterestEquityChangeInRedemptionValue	-42700000	usd
CY2024Q3	us-gaap	Redeemable Noncontrolling Interest Equity Carrying Amount RedeemableNoncontrollingInterestEquityCarryingAmount	397100000	usd
	us-gaap	Payments Of Dividends Minority Interest PaymentsOfDividendsMinorityInterest	216400000	usd
	us-gaap	Payments Of Dividends Minority Interest PaymentsOfDividendsMinorityInterest	206500000	usd
	us-gaap	Payments To Acquire Businesses And Interest In Affiliates PaymentsToAcquireBusinessesAndInterestInAffiliates	41700000	usd
	us-gaap	Payments To Acquire Businesses And Interest In Affiliates PaymentsToAcquireBusinessesAndInterestInAffiliates	60400000	usd
	us-gaap	Proceeds From Divestiture Of Businesses And Interests In Affiliates ProceedsFromDivestitureOfBusinessesAndInterestsInAffiliates	13400000	usd
	us-gaap	Proceeds From Divestiture Of Businesses And Interests In Affiliates ProceedsFromDivestitureOfBusinessesAndInterestsInAffiliates	6300000	usd
CY2023Q3	amg	Affiliate Equity Compensation Expense Including Portion Attributableto Noncontrolling Interest AffiliateEquityCompensationExpenseIncludingPortionAttributabletoNoncontrollingInterest	11500000	usd
CY2024Q3	amg	Affiliate Equity Compensation Expense Including Portion Attributableto Noncontrolling Interest AffiliateEquityCompensationExpenseIncludingPortionAttributabletoNoncontrollingInterest	12100000	usd
	amg	Affiliate Equity Compensation Expense Including Portion Attributableto Noncontrolling Interest AffiliateEquityCompensationExpenseIncludingPortionAttributabletoNoncontrollingInterest	39500000	usd
	amg	Affiliate Equity Compensation Expense Including Portion Attributableto Noncontrolling Interest AffiliateEquityCompensationExpenseIncludingPortionAttributabletoNoncontrollingInterest	46500000	usd
CY2023Q3	us-gaap	Net Income Loss NetIncomeLoss	217000000.0	usd
CY2024Q3	us-gaap	Net Income Loss NetIncomeLoss	123600000	usd
	us-gaap	Net Income Loss NetIncomeLoss	476800000	usd
	us-gaap	Net Income Loss NetIncomeLoss	349500000	usd
CY2023Q3	amg	Adjustments To Additional Paid In Capital Increase Decrease In Carrying Amount Of Redeemable Noncontrolling Interests Issuances AdjustmentsToAdditionalPaidInCapitalIncreaseDecreaseInCarryingAmountOfRedeemableNoncontrollingInterestsIssuances	4500000	usd
CY2024Q3	amg	Adjustments To Additional Paid In Capital Increase Decrease In Carrying Amount Of Redeemable Noncontrolling Interests Issuances AdjustmentsToAdditionalPaidInCapitalIncreaseDecreaseInCarryingAmountOfRedeemableNoncontrollingInterestsIssuances	0	usd
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CY2023Q3	amg	Adjustments To Additional Paid In Capital Increase Decrease In Carrying Amount Of Redeemable Noncontrolling Interests Purchases AdjustmentsToAdditionalPaidInCapitalIncreaseDecreaseInCarryingAmountOfRedeemableNoncontrollingInterestsPurchases	-1900000	usd
CY2024Q3	amg	Adjustments To Additional Paid In Capital Increase Decrease In Carrying Amount Of Redeemable Noncontrolling Interests Purchases AdjustmentsToAdditionalPaidInCapitalIncreaseDecreaseInCarryingAmountOfRedeemableNoncontrollingInterestsPurchases	500000	usd
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CY2023Q3	amg	Increase Decrease In Equity Due To Profit Loss And Net Transfers With Noncontrolling Interests IncreaseDecreaseInEquityDueToProfitLossAndNetTransfersWithNoncontrollingInterests	214400000	usd
CY2024Q3	amg	Increase Decrease In Equity Due To Profit Loss And Net Transfers With Noncontrolling Interests IncreaseDecreaseInEquityDueToProfitLossAndNetTransfersWithNoncontrollingInterests	123100000	usd
	amg	Increase Decrease In Equity Due To Profit Loss And Net Transfers With Noncontrolling Interests IncreaseDecreaseInEquityDueToProfitLossAndNetTransfersWithNoncontrollingInterests	427600000	usd
	amg	Increase Decrease In Equity Due To Profit Loss And Net Transfers With Noncontrolling Interests IncreaseDecreaseInEquityDueToProfitLossAndNetTransfersWithNoncontrollingInterests	324000000.0	usd
CY2023Q3	us-gaap	Income Tax Expense Benefit IncomeTaxExpenseBenefit	77700000	usd
CY2024Q3	us-gaap	Income Tax Expense Benefit IncomeTaxExpenseBenefit	31300000	usd
	us-gaap	Income Tax Expense Benefit IncomeTaxExpenseBenefit	155400000	usd
	us-gaap	Income Tax Expense Benefit IncomeTaxExpenseBenefit	130000000.0	usd
CY2023Q3	amg	Deferred Income Tax Benefit Expense Related To Intangibles DeferredIncomeTaxBenefitExpenseRelatedToIntangibles	-13500000	usd
CY2024Q3	amg	Deferred Income Tax Benefit Expense Related To Intangibles DeferredIncomeTaxBenefitExpenseRelatedToIntangibles	16400000	usd
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	amg	Deferred Income Tax Benefit Expense Related To Intangibles DeferredIncomeTaxBenefitExpenseRelatedToIntangibles	50600000	usd
CY2023Q3	us-gaap	Net Income Loss Available To Common Stockholders Basic NetIncomeLossAvailableToCommonStockholdersBasic	217000000.0	usd
	us-gaap	Incremental Common Shares Attributable To Share Based Payment Arrangements IncrementalCommonSharesAttributableToShareBasedPaymentArrangements	1700000	shares
	us-gaap	Incremental Common Shares Attributable To Share Based Payment Arrangements IncrementalCommonSharesAttributableToShareBasedPaymentArrangements	1900000	shares
CY2023Q3	amg	Settlement Of Redeemable Non Controlling Interests Shares Issued SettlementOfRedeemableNonControllingInterestsSharesIssued	5100000	shares
CY2024Q3	amg	Settlement Of Redeemable Non Controlling Interests Shares Issued SettlementOfRedeemableNonControllingInterestsSharesIssued	1500000	shares
	amg	Settlement Of Redeemable Non Controlling Interests Shares Issued SettlementOfRedeemableNonControllingInterestsSharesIssued	3900000	shares
	amg	Settlement Of Redeemable Non Controlling Interests Shares Issued SettlementOfRedeemableNonControllingInterestsSharesIssued	200000	shares
CY2023Q3	us-gaap	Incremental Common Shares Attributable To Conversion Of Debt Securities IncrementalCommonSharesAttributableToConversionOfDebtSecurities	1700000	shares
CY2024Q3	us-gaap	Incremental Common Shares Attributable To Conversion Of Debt Securities IncrementalCommonSharesAttributableToConversionOfDebtSecurities	1700000	shares
	us-gaap	Incremental Common Shares Attributable To Conversion Of Debt Securities IncrementalCommonSharesAttributableToConversionOfDebtSecurities	1700000	shares
	us-gaap	Incremental Common Shares Attributable To Conversion Of Debt Securities IncrementalCommonSharesAttributableToConversionOfDebtSecurities	1700000	shares
CY2023Q3	us-gaap	Weighted Average Number Of Diluted Shares Outstanding WeightedAverageNumberOfDilutedSharesOutstanding	43400000	shares
CY2024Q3	us-gaap	Weighted Average Number Of Diluted Shares Outstanding WeightedAverageNumberOfDilutedSharesOutstanding	35000000.0	shares
	us-gaap	Weighted Average Number Of Diluted Shares Outstanding WeightedAverageNumberOfDilutedSharesOutstanding	42900000	shares
	us-gaap	Weighted Average Number Of Diluted Shares Outstanding WeightedAverageNumberOfDilutedSharesOutstanding	35200000	shares
CY2024Q3	us-gaap	Treasury Stock Shares Acquired TreasuryStockSharesAcquired	600000	shares
	us-gaap	Treasury Stock Shares Acquired TreasuryStockSharesAcquired	3600000	shares
CY2024Q3	us-gaap	Treasury Stock Acquired Average Cost Per Share TreasuryStockAcquiredAverageCostPerShare	163.23
	us-gaap	Treasury Stock Acquired Average Cost Per Share TreasuryStockAcquiredAverageCostPerShare	158.62
CY2023Q3	us-gaap	Other Comprehensive Income Loss Before Tax OtherComprehensiveIncomeLossBeforeTax	-27300000	usd
CY2023Q3	us-gaap	Other Comprehensive Income Loss Tax OtherComprehensiveIncomeLossTax	3000000.0	usd
CY2023Q3	us-gaap	Other Comprehensive Income Loss Net Of Tax OtherComprehensiveIncomeLossNetOfTax	-30300000	usd
CY2024Q3	us-gaap	Other Comprehensive Income Loss Before Tax OtherComprehensiveIncomeLossBeforeTax	39600000	usd
CY2024Q3	us-gaap	Other Comprehensive Income Loss Tax OtherComprehensiveIncomeLossTax	-600000	usd
CY2024Q3	us-gaap	Other Comprehensive Income Loss Net Of Tax OtherComprehensiveIncomeLossNetOfTax	40200000	usd
	us-gaap	Other Comprehensive Income Loss Before Tax OtherComprehensiveIncomeLossBeforeTax	28300000	usd
	us-gaap	Other Comprehensive Income Loss Tax OtherComprehensiveIncomeLossTax	6800000	usd
	us-gaap	Other Comprehensive Income Loss Net Of Tax OtherComprehensiveIncomeLossNetOfTax	21500000	usd
	us-gaap	Other Comprehensive Income Loss Before Tax OtherComprehensiveIncomeLossBeforeTax	46700000	usd
	us-gaap	Other Comprehensive Income Loss Tax OtherComprehensiveIncomeLossTax	2300000	usd
	us-gaap	Other Comprehensive Income Loss Net Of Tax OtherComprehensiveIncomeLossNetOfTax	44400000	usd
	us-gaap	Other Comprehensive Income Loss Before Reclassifications Net Of Tax OtherComprehensiveIncomeLossBeforeReclassificationsNetOfTax	43800000	usd
	us-gaap	Reclassification From Accumulated Other Comprehensive Income Current Period Net Of Tax ReclassificationFromAccumulatedOtherComprehensiveIncomeCurrentPeriodNetOfTax	-600000	usd
	us-gaap	Other Comprehensive Income Loss Net Of Tax OtherComprehensiveIncomeLossNetOfTax	44400000	usd

Files In Submission

Name	View Source	Status
amg-20240930_cal.xml	Edgar Link	unprocessable
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0001004434-24-000049-index.html	Edgar Link	pending
0001004434-24-000049.txt	Edgar Link	pending
0001004434-24-000049-xbrl.zip	Edgar Link	pending
amg-20240930.htm	Edgar Link	pending
amg-20240930.xsd	Edgar Link	pending
amg-20240930_g1.gif	Edgar Link	pending
amg-20240930_g2.jpg	Edgar Link	pending
amg_09302024xexhibit311.htm	Edgar Link	pending
amg_09302024xexhibit312.htm	Edgar Link	pending
amg_09302024xexhibit321.htm	Edgar Link	pending
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$AMG
AFFILIATED MANAGERS GROUP, INC. Stock $amg

2024 Q4 Form 10-Q Financial Statement

#000100443424000049 Filed on November 07, 2024

Income Statement

Balance Sheet

Cashflow Statement

Facts In Submission

Files In Submission

$AMG AFFILIATED MANAGERS GROUP, INC. Stock $amg

2024 Q4 Form 10-Q Financial Statement

#000100443424000049 Filed on November 07, 2024

Income Statement

Balance Sheet

Cashflow Statement

Facts In Submission

Files In Submission

$AMG
AFFILIATED MANAGERS GROUP, INC. Stock $amg