Other Assets and Liabilities - Summary of Unfunded Loan Commitment (Detail) - USD ($) $ in Thousands	3 Months Ended		12 Months Ended
	Mar. 31, 2022	Mar. 31, 2021	Dec. 31, 2021
Financing Receivable, Allowance for Credit Loss [Roll Forward]
Beginning balance	$ 124,679	$ 173,549	$ 173,549
Increase (decrease) in CECL reserve	(2,500)	(1,400)
Ending balance	122,221	172,100	124,679
U.S. Loans
Financing Receivable, Allowance for Credit Loss [Roll Forward]
Beginning balance	26,885	42,995	42,995
Ending balance	26,241	44,534	26,885
Non-U.S. Loans
Financing Receivable, Allowance for Credit Loss [Roll Forward]
Beginning balance	10,263	27,734	27,734
Ending balance	10,209	24,600	10,263
Unfunded Loan Commitment
Financing Receivable, Allowance for Credit Loss [Roll Forward]
Beginning balance	6,263	10,031	10,031
Increase (decrease) in CECL reserve	(9)	990
Ending balance	6,254	11,021	6,263
Unfunded Loan Commitment | U.S. Loans
Financing Receivable, Allowance for Credit Loss [Roll Forward]
Beginning balance	4,072	6,953	6,953
Increase (decrease) in CECL reserve	209	216
Ending balance	4,281	7,169	4,072
Unfunded Loan Commitment | Non-U.S. Loans
Financing Receivable, Allowance for Credit Loss [Roll Forward]
Beginning balance	2,191	2,994	2,994
Increase (decrease) in CECL reserve	(218)	778
Ending balance	1,973	3,772	2,191
Unique Loans
Financing Receivable, Allowance for Credit Loss [Roll Forward]
Beginning balance	32,657	33,159	33,159
Ending balance	30,897	33,305	32,657
Unique Loans | Unfunded Loan Commitment
Financing Receivable, Allowance for Credit Loss [Roll Forward]
Beginning balance	0	84	84
Increase (decrease) in CECL reserve	0	(4)
Ending balance	0	80	0
Impaired loans
Financing Receivable, Allowance for Credit Loss [Roll Forward]
Beginning balance	54,874	69,661	69,661
Ending balance	54,874	69,661	54,874
Impaired loans | Unfunded Loan Commitment
Financing Receivable, Allowance for Credit Loss [Roll Forward]
Beginning balance	0	0	0
Increase (decrease) in CECL reserve	0	0
Ending balance	$ 0	$ 0	$ 0