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Fair Value Measurements (Tables)

9 Months Ended

Sep. 30, 2025

Fair Value Disclosures [Abstract]

Schedule of Fair Value of Assets and Liabilities Measured on a Recurring Basis

The following tables summarize financial assets and liabilities that are measured at fair value on a recurring basis:

			Fair Value Measurements
	December 31, 2024
			Quoted Prices in Active Markets for Identical Assets (Level 1)		Significant Other Observable Inputs (Level 2)		Significant Unobservable Inputs (Level 3)
Financial Assets
Investments in equity securities(1)	$32.3		$32.3		$—		$—
Investments in debt securities(1)	24.3		—		24.3		—
Financial Liabilities(2)
Contingent payment obligations	$5.7		$—		$—		$5.7
Affiliate equity purchase obligations	54.8		—		—		54.8

			Fair Value Measurements
	September 30, 2025
			Quoted Prices in Active Markets for Identical Assets (Level 1)		Significant Other Observable Inputs (Level 2)		Significant Unobservable Inputs (Level 3)
Financial Assets
Investments in equity securities(1)	$37.1		$37.1		$—		$—
Investments in debt securities(1)	48.4		—		48.4		—
Financial Liabilities(2)
Contingent payment obligations	$0.0		$—		$—		$0.0
Affiliate equity purchase obligations	235.2		—		—		235.2

___________________________

(1)Amounts are recorded in Investments on the Consolidated Balance Sheets.

(2)Amounts are recorded in Other liabilities on the Consolidated Balance Sheets.

Schedule of Changes in Level 3 Assets and Liabilities for Affiliate Equity Repurchase Obligation

The following tables present the changes in Level 3 liabilities:

		For the Three Months Ended September 30,
		2024				2025
		Contingent Payment Obligations		Affiliate Equity Purchase Obligations		Contingent Payment Obligations		Affiliate Equity Purchase Obligations
Balance, beginning of period		$7.9		$53.9		$0.0		$117.9
Purchases and issuances(1)		—		10.1		—		112.3
Settlements and reductions		—		(5.0)		—		(10.4)
Net realized and unrealized (gains) losses(2)		(1.4)		(0.1)		—		15.4
Balance, end of period		$6.5		$58.9		$0.0		$235.2
Net change in unrealized (gains) losses relating to instruments still held at the reporting date(1)		$(1.4)		$(0.5)		$—		$15.2

		For the Nine Months Ended September 30,
		2024				2025
		Contingent Payment Obligations		Affiliate Equity Purchase Obligations		Contingent Payment Obligations		Affiliate Equity Purchase Obligations
Balance, beginning of period		$14.7		$53.9		$5.7		$54.8
Purchases and issuances(1)		—		66.3		—		205.4
Settlements and reductions		—		(62.1)		(4.9)		(53.8)
Net realized and unrealized (gains) losses(2)		(8.2)		0.8		(0.8)		28.8
Balance, end of period		$6.5		$58.9		$0.0		$235.2
Net change in unrealized (gains) losses relating to instruments still held at the reporting date(1)		$(8.2)		$0.4		$(0.1)		$29.6

___________________________

(1)Affiliate equity purchase obligation activity includes transfers from Redeemable non-controlling interests.

(2)Gains and losses resulting from changes to expected payments related to contingent payment obligations and the accretion

of these obligations are included in Other expenses (net) and included in Interest expense, respectively, in the Consolidated

Statements of Income.  Changes to the redemption value of Affiliate equity purchase obligations are included in

Compensation and related expenses in the Consolidated Statements of Income.

Schedule of Quantitative Information used in Valuing Level 3 Liabilities

The following table presents certain quantitative information about the significant unobservable inputs used in valuing the

Company’s Level 3 fair value measurements:

	Quantitative Information about Level 3 Fair Value Measurements
					December 31, 2024						September 30, 2025
	Valuation Techniques		Unobservable Input		Fair Value		Range		Weighted Average(1)		Fair Value		Range		Weighted Average(1)
Contingent payment obligations	Monte Carlo Simulation		Volatility		$5.7		18%		18%		$0.0		17%		17%
			Discount rates				4%		4%				4%		4%
Affiliate equity purchase obligations	Discounted cash flow		Growth rates(2)		$54.8		(4)% - 9%		1%		$235.2		(4)% - 6%		2%
			Discount rates				12% - 19%		14%				12% - 19%		14%

___________________________

(1)Calculated by comparing the relative fair value of an obligation to its respective total.

(2)Represents growth rates of asset- and performance-based fees.

Schedule of Other Financial Assets and Liabilities Not Carried at Fair Value

The following table summarizes the Company’s other financial liabilities not carried at fair value:

	December 31, 2024				September 30, 2025
	Carrying Value		Fair Value		Carrying Value		Fair Value		Fair Value Hierarchy
Senior notes	$1,097.4		$1,062.9		$747.7		$740.9		Level 2
Junior subordinated notes	1,216.0		1,035.6		1,216.1		1,031.2		Level 2
Junior convertible securities	341.7		372.2		341.7		437.4		Level 2

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Summary of Other Financial Liabilities Not Carried at Fair Value [Table Text Block]

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Tabular disclosure of input and valuation technique used to measure fair value and change in valuation approach and technique for each separate class of asset and liability measured on recurring and nonrecurring basis.

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Tabular disclosure of the fair value measurement of liabilities using significant unobservable inputs (Level 3), a reconciliation of the beginning and ending balances, separately presenting changes attributable to the following: (1) total gains or losses for the period (realized and unrealized), segregating those gains or losses included in earnings (or changes in net assets), and gains or losses recognized in other comprehensive income (loss) and a description of where those gains or losses included in earnings (or changes in net assets) are reported in the statement of income (or activities); (2) purchases, sales, issues, and settlements (each type disclosed separately); and (3) transfers in and transfers out of Level 3 (for example, transfers due to changes in the observability of significant inputs) by class of liability.

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-Topic 820
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Tabular disclosure of assets and liabilities, including [financial] instruments measured at fair value that are classified in stockholders' equity, if any, that are measured at fair value on a recurring basis. The disclosures contemplated herein include the fair value measurements at the reporting date by the level within the fair value hierarchy in which the fair value measurements in their entirety fall, segregating fair value measurements using quoted prices in active markets for identical assets (Level 1), significant other observable inputs (Level 2), and significant unobservable inputs (Level 3).

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