Investments - Summary of Financial Information for Company's Equity Method Investments (Detail) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2021	Dec. 31, 2020	Dec. 31, 2019	Dec. 31, 2018
Statements of operations:
Total revenues	$ 2,015,364	$ 2,056,761	$ 2,104,606
Total expenses	2,178,215	1,991,537	2,041,026
Consolidated net income (loss)	153,488	50,918	66,816
Statements of financial condition:
Total assets	3,342,166	3,953,242
Total liabilities	2,660,090	3,121,271
Total equity	663,315	811,297	729,106	$ 855,459
Total liabilities, redeemable partnership interest, and equity	3,342,166	3,953,242
Equity Method Investment Nonconsolidated Investee
Statements of operations:
Total revenues	108,458	94,744	77,211
Total expenses	82,581	71,241	61,680
Consolidated net income (loss)	25,877	23,503	$ 15,531
Statements of financial condition:
Total assets	150,098	121,498
Total equity	55,984	49,478
Total liabilities, redeemable partnership interest, and equity	150,098	121,498
Equity Method Investment Nonconsolidated Investee | Cash and cash equivalents
Statements of financial condition:
Total assets	104,855	89,627
Equity Method Investment Nonconsolidated Investee | Fixed assets, net
Statements of financial condition:
Total assets	2,603	2,806
Equity Method Investment Nonconsolidated Investee | Other assets
Statements of financial condition:
Total assets	42,640	29,065
Equity Method Investment Nonconsolidated Investee | Payables to related parties
Statements of financial condition:
Total liabilities	2,000	2,000
Equity Method Investment Nonconsolidated Investee | Other liabilities
Statements of financial condition:
Total liabilities	$ 92,114	$ 70,020