Significant Accounting Policies (Details)	3 Months Ended		9 Months Ended
	Sep. 30, 2022 USD ($)	Sep. 30, 2021 USD ($)	Sep. 30, 2022 USD ($) segment	Sep. 30, 2021 USD ($)	Jul. 01, 2022 USD ($)	Dec. 31, 2021 USD ($)
Business Acquisition [Line Items]
Goodwill	$ 3,719,880,000		$ 3,719,880,000			$ 3,091,763,000
Number of reporting segments | segment			1
Intangible assets, net of accumulated amortization	332,648,000		$ 332,648,000			41,531,000
Finite-lived intangible assets subject to amortization, net	317,400,000		317,400,000			26,300,000
Indefinite-lived intangible assets not subject to amortization	15,200,000		15,200,000
Gross carrying amount of intangible assets	359,600,000		359,600,000			53,800,000
Accumulated amortization of intangible assets	42,200,000		42,200,000			27,500,000
Amortization of intangible assets	12,256,000	$ 1,502,000	14,652,000	$ 4,502,000
Estimated annual amortization expense for 2023	49,300,000		49,300,000
Estimated annual amortization expense for 2024	49,100,000		49,100,000
Estimated annual amortization expense for 2025	48,000,000		48,000,000
Estimated annual amortization expense for 2026	46,600,000		46,600,000
Estimated annual amortization expense for 2027	25,500,000		25,500,000
Impairment of intangible assets	0	$ 0
Contingent consideration liability	273,145,000		$ 273,145,000			38,260,000
Minimum
Business Acquisition [Line Items]
Intangible assets acquired, estimated useful life			5 years
Maximum
Business Acquisition [Line Items]
Intangible assets acquired, estimated useful life			20 years
CarVal Investors, L.P.
Business Acquisition [Line Items]
Percentage of interests acquired					100.00%
Equity interest contributed to affiliate					100.00%
Goodwill	627,600,000		$ 627,600,000		$ 627,593,000
Business combination, recognized identifiable assets acquired and liabilities assumed, finite-lived intangibles					303,000,000
Contingent consideration liability	227,100,000		227,100,000		$ 227,100,000
Sanford C Bernstein Inc Acquisition
Business Acquisition [Line Items]
Goodwill	2,800,000,000		2,800,000,000			2,800,000,000
Series of Individually Immaterial Business Acquisitions
Business Acquisition [Line Items]
Goodwill	$ 291,900,000		$ 291,900,000			$ 291,000,000