Commitments and Contingencies - Schedule of Principal Debt Repayments (Detail) - USD ($) $ in Thousands	3 Months Ended
Mar. 31, 2022	Dec. 31, 2021
Debt Instrument [Line Items]
2022	$ 394,804
2023	1,004,718
2024	3,941,558
2025	1,828,956
2026	6,129,112
Thereafter	2,891,554
Net book value	$ 16,190,702
Amortization percentage	1.00%
Securitized debt obligations excluded from contractual obligations	$ 2,900,000
Nonconsolidated securitized debt excluded from contractual obligations	1,800,000
Loan participations sold, net, Face Amount	244,367	$ 0
Senior Participation
Debt Instrument [Line Items]
Loan participations sold, net, Face Amount	244,367
Secured Debt
Debt Instrument [Line Items]
2022	46,650
2023	770,980
2024	3,927,820
2025	1,345,452
2026	4,834,793
Thereafter	2,191,554
Net book value	13,117,249
Asset-Specific Debt
Debt Instrument [Line Items]
2022	0
2023	0
2024	0
2025	469,766
2026	0
Thereafter	0
Net book value	469,766
Term Loans
Debt Instrument [Line Items]
2022	10,304
2023	13,738
2024	13,738
2025	13,738
2026	1,294,319
Thereafter	0
Net book value	1,345,837
Senior Secured Notes
Debt Instrument [Line Items]
2022	0
2023	0
2024	0
2025	0
2026	0
Thereafter	400,000
Net book value	400,000
Convertible Notes
Debt Instrument [Line Items]
2022	337,850
2023	220,000
2024	0
2025	0
2026	0
Thereafter	300,000
Net book value	$ 857,850

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Participating Mortgage Loans, Participation Liabilities, Principal Amount

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Amount, after unamortized (discount) premium and debt issuance costs, of long-term debt. Includes, but not limited to, notes payable, bonds payable, debentures, mortgage loans and commercial paper. Excludes capital lease obligations.

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