Consolidation - Summary of Assets and Liabilities Measured at Fair Value on Recurring Basis (Details) - USD ($) $ in Thousands	Dec. 31, 2022	Dec. 31, 2021
Assets
Cash equivalents	$ 287,126	$ 307,277
Total assets measured at fair value	374,279	400,933
Liabilities
Total liabilities measured at fair value	78,100	88,400
Level 1
Assets
Cash equivalents	287,126	307,277
Total assets measured at fair value	374,279	400,933
Liabilities
Total liabilities measured at fair value	0	0
Level 2
Assets
Cash equivalents	0	0
Total assets measured at fair value	0	0
Liabilities
Total liabilities measured at fair value	0	0
Level 3
Assets
Cash equivalents	0	0
Total assets measured at fair value	0	0
Liabilities
Total liabilities measured at fair value	78,100	88,400
Fair Value, Measurements, Recurring | Consolidated Investment Products
Assets
Cash equivalents	249,003	205,192
Total assets measured at fair value	2,439,116	2,345,430
Liabilities
Notes payable	2,083,314	2,033,617
Short sales	414	515
Total liabilities measured at fair value	2,083,728	2,034,132
Fair Value, Measurements, Recurring | Debt investments | Consolidated Investment Products
Assets
Investments	2,161,571	2,110,704
Fair Value, Measurements, Recurring | Equity investments | Consolidated Investment Products
Assets
Investments	28,542	29,534
Fair Value, Measurements, Recurring | Level 1 | Consolidated Investment Products
Assets
Cash equivalents	249,003	205,192
Total assets measured at fair value	274,249	231,576
Liabilities
Notes payable	0	0
Short sales	414	515
Total liabilities measured at fair value	414	515
Fair Value, Measurements, Recurring | Level 1 | Debt investments | Consolidated Investment Products
Assets
Investments	243	273
Fair Value, Measurements, Recurring | Level 1 | Equity investments | Consolidated Investment Products
Assets
Investments	25,003	26,111
Fair Value, Measurements, Recurring | Level 2 | Consolidated Investment Products
Assets
Cash equivalents	0	0
Total assets measured at fair value	2,121,286	2,110,697
Liabilities
Notes payable	2,083,314	2,033,617
Short sales	0	0
Total liabilities measured at fair value	2,083,314	2,033,617
Fair Value, Measurements, Recurring | Level 2 | Debt investments | Consolidated Investment Products
Assets
Investments	2,119,082	2,107,736
Fair Value, Measurements, Recurring | Level 2 | Equity investments | Consolidated Investment Products
Assets
Investments	2,204	2,961
Fair Value, Measurements, Recurring | Level 3 | Consolidated Investment Products
Assets
Cash equivalents	0	0
Total assets measured at fair value	43,581	3,157
Liabilities
Notes payable	0	0
Short sales	0	0
Total liabilities measured at fair value	0	0
Fair Value, Measurements, Recurring | Level 3 | Debt investments | Consolidated Investment Products
Assets
Investments	42,246	2,695
Fair Value, Measurements, Recurring | Level 3 | Equity investments | Consolidated Investment Products
Assets
Investments	$ 1,335	$ 462