Fair Value of Financial Instruments - Additional Information (Details) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2023	Dec. 31, 2022
Investments
Fair Value, Balance Sheet Grouping, Financial Statement Captions
Transfers out of Level III	$ 19,810	$ 172
Transfers into Level III	0	0
Measured on a recurring basis
Fair Value, Balance Sheet Grouping, Financial Statement Captions
Total assets	1,064,294	937,014
Level III Investments at fair value attributable to noncontrolling interests	285,881	273,892
Measured on a recurring basis | Noncontrolling Interests
Fair Value, Balance Sheet Grouping, Financial Statement Captions
Level III Investments at fair value attributable to noncontrolling interests	211,100	200,700
Level III
Fair Value, Balance Sheet Grouping, Financial Statement Captions
Total assets	$ 233,000	$ 200,500
Percentage of Level III assets to financial instruments measured at fair value	21.90%	21.40%
Transfers out of Level III	$ 19,800
Transfers into Level III		$ 3,600
Level III | Investments
Fair Value, Balance Sheet Grouping, Financial Statement Captions
Level III Investments at fair value attributable to noncontrolling interests	224,300
Level III | Measured on a recurring basis
Fair Value, Balance Sheet Grouping, Financial Statement Captions
Total assets	232,983	200,488
Level III Investments at fair value attributable to noncontrolling interests	224,280	191,845
Level III | Measured on a recurring basis | Noncontrolling Interests
Fair Value, Balance Sheet Grouping, Financial Statement Captions
Level III Investments at fair value attributable to noncontrolling interests	177,000	148,700
Level I | Equity Securities | Investments
Fair Value, Balance Sheet Grouping, Financial Statement Captions
Equity securities subject to contractual sale restrictions	5,100
Level I | Measured on a recurring basis
Fair Value, Balance Sheet Grouping, Financial Statement Captions
Total assets	411,740	410,480
Level III Investments at fair value attributable to noncontrolling interests	$ 61,601	$ 82,047