Loans Receivable, Net - Overall Statistics for Loans Receivable Portfolio (Detail) $ in Thousands	3 Months Ended	12 Months Ended
Mar. 31, 2023 USD ($) SecurityLoan	Dec. 31, 2022 USD ($) SecurityLoan
Accounts, Notes, Loans and Financing Receivable [Line Items]
Number of loans \| SecurityLoan	199	203
Principal balance	$ 25,020,489	$ 25,160,343
Net book value	$ 24,559,773	$ 24,691,743
Weighted-average maximum maturity (years)	2 years 10 months 24 days	3 years 1 month 6 days
Percentage of Portfolio	100.00%	100.00%
Unfunded Loan Commitment
Accounts, Notes, Loans and Financing Receivable [Line Items]
Unfunded loan commitments	$ 3,382,489	$ 3,806,153
Prepayment Restrictions Including Yield Maintenance Lock Out Provisions
Accounts, Notes, Loans and Financing Receivable [Line Items]
Percentage of Portfolio	36.00%	50.00%
Without Prepayment Restrictions
Accounts, Notes, Loans and Financing Receivable [Line Items]
Percentage of Portfolio	64.00%	50.00%
LIBOR and SOFR
Accounts, Notes, Loans and Financing Receivable [Line Items]
Weighted-average cash coupon (percentage)	3.46%	3.44%
Weighted-average all-in yield (percentage)	3.85%	3.84%

Financing Receivable, Commitment to Lend

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- Definition

Financing Receivable, Number of Loans

+ References

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- Definition

Financing Receivable, Percentage Of Loan Portfolio

+ References

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- Definition

Mortgage loan on real estate final maturity term.

+ References

No definition available.

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- Definition

Weighted Average Cash Coupon Rate

+ References

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- Definition

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.

+ References

No definition available.

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- Definition

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

+ References

Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 326
-SubTopic 20
-Section 45
-Paragraph 1
-URI https://asc.fasb.org/extlink&oid=124255206&loc=SL82895884-210446

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- Definition

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

+ References

Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 310
-SubTopic 20
-Section 45
-Paragraph 2
-URI https://asc.fasb.org/extlink&oid=6378536&loc=d3e10095-111533

Reference 2: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 942
-SubTopic 210
-Section S99
-Paragraph 1
-Subparagraph (SX 210.9-03(7))
-URI https://asc.fasb.org/extlink&oid=126897435&loc=d3e534808-122878

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- Definition

Yield on the receivable, on which interest has been imputed, as calculated from its issuance value or purchase price. The calculated effective interest rate considers factors such as the issued face value or price paid for the receivable, the time period between payments, and the time until maturity [full receipt] of the receivable.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 835
-SubTopic 30
-Section 45
-Paragraph 2
-URI https://asc.fasb.org/extlink&oid=124435984&loc=d3e28551-108399

Reference 2: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 835
-SubTopic 30
-Section 50
-Paragraph 1
-URI https://asc.fasb.org/extlink&oid=124429444&loc=SL124452920-239629

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