Consolidated Company-Sponsored Investment Funds - Fair Value (Details) - USD ($) $ in Thousands	Jun. 30, 2022	Dec. 31, 2021
VIEs
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Derivatives	$ 2,043	$ 5,887
Derivatives	18,620	18,342
Recurring
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Derivatives	27,347	15,422
Derivatives	12,524	16,923
Total liabilities measured at fair value	54,960	59,011
Recurring | Level 1
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Investments	116,921	155,904
Derivatives	1,724	392
Total assets measured at fair value	243,771	307,452
Derivatives	348	1,186
Total liabilities measured at fair value	348	5,014
Recurring | Level 2
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Investments	30,783	39,284
Derivatives	25,623	15,030
Total assets measured at fair value	1,803,279	1,558,142
Derivatives	12,176	15,737
Total liabilities measured at fair value	12,176	15,737
Recurring | Level 3
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Investments	119	126
Derivatives	0	0
Total assets measured at fair value	119	126
Derivatives	0	0
Total liabilities measured at fair value	42,436	38,260
Recurring | Company-sponsored investment funds
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Total assets measured at fair value	460,548	618,912
Total liabilities measured at fair value	18,620	18,342
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	74,779	166,037
Total liabilities measured at fair value	15,067	16,291
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	385,769	449,518
Total liabilities measured at fair value	3,553	2,051
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	3,357
Total liabilities measured at fair value	0	0
Recurring | VIEs
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Investments	458,505	613,025
Derivatives	2,043	5,887
Derivatives	18,620	18,342
Recurring | VIEs | Level 1
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Investments	74,225	165,415
Derivatives	554	622
Derivatives	15,067	16,291
Recurring | VIEs | Level 2
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Investments	384,280	444,253
Derivatives	1,489	5,265
Derivatives	3,553	2,051
Recurring | VIEs | Level 3
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Investments	0	3,357
Derivatives	0	0
Derivatives	$ 0	$ 0