Other Assets and Liabilities - Summary of Unfunded Loan Commitment (Detail) - USD ($) $ in Thousands	3 Months Ended
	Sep. 30, 2023	Jun. 30, 2023	Mar. 31, 2023	Sep. 30, 2022	Jun. 30, 2022	Mar. 31, 2022
Financing Receivable, Excluding Accrued Interest, Allowance for Credit Loss [Roll Forward]
Beginning balance	$ 363,875	$ 336,591	$ 326,137	$ 133,024	$ 122,221	$ 124,679
Increase (decrease) in CECL reserve	99,548	27,284	10,454	11,407	10,803	(2,458)
Ending balance	463,423	363,875	336,591	144,431	133,024	122,221
U.S. loans
Financing Receivable, Excluding Accrued Interest, Allowance for Credit Loss [Roll Forward]
Beginning balance	74,393	73,194	67,880	33,311	26,241	26,885
Increase (decrease) in CECL reserve	(5,639)	1,199	5,314	8,280	7,070	(644)
Ending balance	68,754	74,393	73,194	41,591	33,311	26,241
Non-U.S. loans
Financing Receivable, Excluding Accrued Interest, Allowance for Credit Loss [Roll Forward]
Beginning balance	28,992	19,696	22,519	11,344	10,209	10,263
Increase (decrease) in CECL reserve	(2,336)	9,296	(2,823)	45	1,135	(54)
Ending balance	26,656	28,992	19,696	11,389	11,344	10,209
Unfunded Loan Commitment
Financing Receivable, Excluding Accrued Interest, Allowance for Credit Loss [Roll Forward]
Beginning balance	16,272	15,749	16,380	8,434	6,254	6,263
Increase (decrease) in CECL reserve	(2,648)	523	(631)	841	2,180	(9)
Ending balance	13,624	16,272	15,749	9,275	8,434	6,254
Unfunded Loan Commitment | U.S. loans
Financing Receivable, Excluding Accrued Interest, Allowance for Credit Loss [Roll Forward]
Beginning balance	11,196	11,600	11,748	6,323	4,281	4,072
Increase (decrease) in CECL reserve	(1,614)	(404)	(148)	527	2,042	209
Ending balance	9,582	11,196	11,600	6,850	6,323	4,281
Unfunded Loan Commitment | Non-U.S. loans
Financing Receivable, Excluding Accrued Interest, Allowance for Credit Loss [Roll Forward]
Beginning balance	5,076	4,149	4,632	2,111	1,973	2,191
Increase (decrease) in CECL reserve	(1,034)	927	(483)	314	138	(218)
Ending balance	4,042	5,076	4,149	2,425	2,111	1,973
Unique loans
Financing Receivable, Excluding Accrued Interest, Allowance for Credit Loss [Roll Forward]
Beginning balance	46,089	46,443	45,960	33,495	30,897	32,657
Increase (decrease) in CECL reserve	(627)	(354)	483	3,082	2,598	(1,760)
Ending balance	45,462	46,089	46,443	36,577	33,495	30,897
Unique loans | Unfunded Loan Commitment
Financing Receivable, Excluding Accrued Interest, Allowance for Credit Loss [Roll Forward]
Beginning balance	0	0	0	0	0	0
Increase (decrease) in CECL reserve	0	0	0	0	0	0
Ending balance	0	0	0	0	0	0
Impaired loans
Financing Receivable, Excluding Accrued Interest, Allowance for Credit Loss [Roll Forward]
Beginning balance	214,401	197,258	189,778	54,874	54,874	54,874
Increase (decrease) in CECL reserve	108,150	17,143	7,480	0	0	0
Ending balance	322,551	214,401	197,258	54,874	54,874	54,874
Impaired loans | Unfunded Loan Commitment
Financing Receivable, Excluding Accrued Interest, Allowance for Credit Loss [Roll Forward]
Beginning balance	0	0	0	0	0	0
Increase (decrease) in CECL reserve	0	0	0	0	0	0
Ending balance	$ 0	$ 0	$ 0	$ 0	$ 0	$ 0