Consolidated Company-Sponsored Investment Funds - Narrative (Details)	3 Months Ended		9 Months Ended
	Sep. 30, 2022 USD ($)	Sep. 30, 2021 USD ($)	Sep. 30, 2022 USD ($) fund	Sep. 30, 2021 USD ($)	Dec. 31, 2021 USD ($)
Derivative [Line Items]
Gains (losses) on derivative instruments	$ 14,539,000	$ 1,895,000	$ 56,370,000	$ (7,183,000)
Cash collateral payable to trade counterparties	16,000,000		16,000,000		$ 2,900,000
Cash collateral received	0		0		5,600,000
Advisory fee receivables	215,718,000		215,718,000		185,653,000
VIEs
Derivative [Line Items]
Futures, forwards and swaps held	(16,700,000)		(16,700,000)		12,500,000
Gains (losses) on derivative instruments	(4,900,000)	(1,500,000)	(10,100,000)	(800,000)
Cash collateral payable to trade counterparties	1,649,000		1,649,000		904,000
Cash collateral received	5,573,000		5,573,000		1,824,000
VOEs
Derivative [Line Items]
Futures, forwards and swaps held	9,211		9,211		0
Gains (losses) on derivative instruments	0	$ 0	0	$ 900,000
Cash collateral payable to trade counterparties	0		0		0
Cash collateral received	0		0		0
Non-consolidated VIEs
Derivative [Line Items]
Net assets	39,900,000,000		39,900,000,000		68,900,000,000
Maximum risk of loss in investment in VIEs	4,800,000		4,800,000		8,800,000
Advisory fee receivables	$ 46,800,000		$ 46,800,000		75,700,000
Seed capital
Derivative [Line Items]
Number of deconsolidated funds | fund			5
Seed investment, deconsolidated amount					$ 61,800,000