Consolidated Company-Sponsored Investment Funds - Fair Value (Details) - USD ($) $ in Thousands	Mar. 31, 2023	Dec. 31, 2022
VIEs
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Derivatives - VIEs	$ 3,670	$ 7,552
Derivatives	16,311	21,540
Recurring
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Derivatives - VIEs	16,687	24,712
Derivatives	16,411	13,712
Total liabilities measured at fair value	264,596	261,021
Recurring | Level 1
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Investments - VIEs	128,865	136,344
Derivatives - VIEs	4	1,768
Total assets measured at fair value	224,559	233,633
Derivatives	4,878	162
Total liabilities measured at fair value	4,878	162
Recurring | Level 2
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Investments - VIEs	28,255	27,799
Derivatives - VIEs	16,683	22,944
Total assets measured at fair value	1,099,576	1,572,448
Derivatives	11,533	13,550
Total liabilities measured at fair value	11,533	13,550
Recurring | Level 3
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Investments - VIEs	170	129
Derivatives - VIEs	0	0
Total assets measured at fair value	170	129
Derivatives	0	0
Total liabilities measured at fair value	248,185	247,309
Recurring | Company-sponsored investment funds
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Total assets measured at fair value	547,009	524,088
Total liabilities measured at fair value	16,311	21,540
Recurring | Company-sponsored investment funds | Level 1
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Total assets measured at fair value	143,808	131,235
Total liabilities measured at fair value	14,830	14,932
Recurring | Company-sponsored investment funds | Level 2
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Total assets measured at fair value	403,201	392,853
Total liabilities measured at fair value	1,481	6,608
Recurring | Company-sponsored investment funds | Level 3
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Total assets measured at fair value	0	0
Total liabilities measured at fair value	0	0
Recurring | VIEs
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Investments - VIEs	526,530	516,536
Derivatives - VIEs	3,670	7,552
Derivatives	16,311	21,540
Recurring | VIEs | Level 1
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Investments - VIEs	125,788	129,706
Derivatives - VIEs	1,211	1,529
Derivatives	14,830	14,932
Recurring | VIEs | Level 2
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Investments - VIEs	400,742	386,830
Derivatives - VIEs	2,459	6,023
Derivatives	1,481	6,608
Recurring | VIEs | Level 3
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Investments - VIEs	0	0
Derivatives - VIEs	0	0
Derivatives	0	$ 0
Recurring | VOEs
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Investments - VIEs	16,809
Recurring | VOEs | Level 1
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Investments - VIEs	16,809
Recurring | VOEs | Level 2
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Investments - VIEs	0
Recurring | VOEs | Level 3
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Investments - VIEs	$ 0