Commitments and Contingencies - Schedule of Principal Debt Repayments (Detail) - USD ($) $ in Thousands	3 Months Ended
Mar. 31, 2023	Dec. 31, 2022
Debt Instrument [Line Items]
2023 (remaining)	$ 367,233
2024	3,402,778
2025	1,878,987
2026	6,250,807
2027	4,083,966
Thereafter	1,742,256
Net book value	$ 17,726,027
Amortization percentage	1.00%
Securitized debt obligations excluded from contractual obligations	$ 2,700,000
Nonconsolidated securitized debt excluded from contractual obligations	1,700,000
Net loan exposure, loan participations sold	229,500	$ 224,700
Loan participations sold, net, Face Amount	229,468	$ 224,744
Secured Debt
Debt Instrument [Line Items]
2023 (remaining)	350,736
2024	3,380,781
2025	1,180,470
2026	4,948,232
2027	3,343,409
Thereafter	847,807
Net book value	14,051,435
Asset-Specific Debt
Debt Instrument [Line Items]
2023 (remaining)	0
2024	0
2025	676,520
2026	0
2027	32,299
Thereafter	114,054
Net book value	822,873
Term Loans
Debt Instrument [Line Items]
2023 (remaining)	16,497
2024	21,997
2025	21,997
2026	1,302,575
2027	8,258
Thereafter	780,395
Net book value	2,151,719
Senior Secured Notes
Debt Instrument [Line Items]
2023 (remaining)	0
2024	0
2025	0
2026	0
2027	400,000
Thereafter	0
Net book value	400,000
Convertible Notes
Debt Instrument [Line Items]
2023 (remaining)	0
2024	0
2025	0
2026	0
2027	300,000
Thereafter	0
Net book value	$ 300,000

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