Loans Receivable, Net - Overall Statistics for Loans Receivable Portfolio (Detail) $ in Thousands	6 Months Ended	12 Months Ended
Jun. 30, 2024 USD ($)	Jun. 30, 2024 USD ($) loan	Jun. 30, 2024 USD ($) security_loan	Jun. 30, 2024 USD ($)	Dec. 31, 2023 USD ($)	Dec. 31, 2023 USD ($) loan	Dec. 31, 2023 USD ($) security_loan	Dec. 31, 2023 USD ($)	Jun. 30, 2023 USD ($)
Accounts, Notes, Loans and Financing Receivable [Line Items]
Number of loans		166	166			178	178
Principal balance	$ 23,010,660	$ 23,010,660	$ 23,010,660	$ 23,010,660	$ 23,923,719	$ 23,923,719	$ 23,923,719	$ 23,923,719
Net book value	21,976,910	21,976,910	21,976,910	21,976,910	23,210,076	23,210,076	23,210,076	23,210,076
Current expected credit loss reserves for unfunded loan commitments	$ 9,946	$ 9,946	$ 9,946	$ 9,946	$ 15,371	$ 15,371	$ 15,371	$ 15,371	$ 16,300
Weighted-average cash coupon (percentage)	3.35%	3.35%	3.35%	3.35%	3.37%	3.37%	3.37%	3.37%
Weighted-average all-in yield (percentage)				3.67%				3.71%
Weighted-average maximum maturity (years)	2 years 1 month 6 days				2 years 4 months 24 days
Debt Instrument, Variable Interest Rate, Type [Extensible Enumeration]	Secured Overnight Financing Rate (SOFR)				Secured Overnight Financing Rate (SOFR)
Percent of loans subject to prepayment restrictions	12.00%	12.00%	12.00%	12.00%	14.00%	14.00%	14.00%	14.00%
Percent of loans not subject to prepayment restrictions	88.00%	88.00%	88.00%	88.00%	86.00%	86.00%	86.00%	86.00%
Interest Rate Swaps
Accounts, Notes, Loans and Financing Receivable [Line Items]
Notional amount	$ 229,900	$ 229,900	$ 229,900	$ 229,900	$ 229,900	$ 229,900	$ 229,900	$ 229,900
Unfunded Loan Commitment
Accounts, Notes, Loans and Financing Receivable [Line Items]
Number of loans \| loan		89
Current expected credit loss reserves for unfunded loan commitments	$ 1,826,350	$ 1,826,350	$ 1,826,350	$ 1,826,350	$ 2,430,664	$ 2,430,664	$ 2,430,664	$ 2,430,664

Financing Receivable, Basis Spread on Variable Rate, Weighted Average All-In Yield

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Financing Receivable, Number of Loans

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Mortgage Loan On Real Estate Final Maturity Term

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Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table.

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Indicates type of variable interest rate on debt instrument.

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Nominal or face amount used to calculate payment on derivative.

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Amortized cost excluding accrued interest, after allowance for credit loss, of financing receivable. Excludes net investment in lease.

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Amortized cost excluding accrued interest, before allowance for credit loss, fee, and loan in process, of financing receivable. Excludes net investment in lease.

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Amount of expected credit loss for credit exposure on off-balance-sheet commitment, including but not limited to, loan commitment, standby letter of credit, financial guarantee not accounted for as insurance. Excludes off-balance sheet credit exposure accounted for as insurance and instrument accounted for under derivatives and hedging.

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