Schedule IV - Mortgage Loans on Real Estate Footnotes (Detail) $ in Thousands	12 Months Ended
Dec. 31, 2024 USD ($) loan	Dec. 31, 2024 USD ($) security_loan	Dec. 31, 2023 USD ($) loan	Dec. 31, 2023 USD ($) security_loan	Dec. 31, 2022 USD ($)
SEC Schedule, 12-29, Real Estate Companies, Investment in Mortgage Loans on Real Estate [Line Items]
Tax basis of loans	$ 18,600,000	$ 18,600,000
Aggregate CECL Reserve	$ 733,936	$ 733,936	$ 576,936	$ 576,936	$ 326,137
Number of loans	130	130	178	178
Principal balance	$ 19,047,518	$ 19,047,518	$ 23,787,012	$ 23,787,012	$ 25,017,880
Level 3 \| Fair Value, Nonrecurring
SEC Schedule, 12-29, Real Estate Companies, Investment in Mortgage Loans on Real Estate [Line Items]
Number of loans \| loan	13
Principal balance	$ 1,800,000	1,800,000
Impaired loans
SEC Schedule, 12-29, Real Estate Companies, Investment in Mortgage Loans on Real Estate [Line Items]
Aggregate CECL Reserve	$ 580,700	580,700
Number of loans \| loan	13
Principal balance	$ 1,827,561	$ 1,827,561	$ 1,877,279	$ 1,877,279

Financing Receivable, Number Of Loans

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- Definition

Amount of federal income tax basis of investment in mortgage loan on real estate by entity with substantial portion of business acquiring and holding investment real estate or interest in real estate.

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Name Regulation S-X (SX)
-Number 210
-Section 12
-Subsection 29
-Paragraph Column G
-Footnote 8
-Publisher SEC

Reference 2: http://www.xbrl.org/2003/role/disclosureRef
-Topic 948
-SubTopic 310
-Name Accounting Standards Codification
-Section S99
-Paragraph 1
-Subparagraph (SX 210.12-29(Column G)(Footnote 8))
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147479628/948-310-S99-1

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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

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Name Regulation S-X (SX)
-Number 210
-Section 12
-Subsection 29
-Publisher SEC

Reference 2: http://www.xbrl.org/2003/role/disclosureRef
-Topic 948
-SubTopic 310
-Name Accounting Standards Codification
-Section S99
-Paragraph 1
-Subparagraph (SX 210.12-29)
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147479628/948-310-S99-1

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

+ References

Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef
-Topic 326
-SubTopic 20
-Name Accounting Standards Codification
-Section 45
-Paragraph 1
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147479344/326-20-45-1

Reference 2: http://www.xbrl.org/2003/role/disclosureRef
-Topic 326
-SubTopic 20
-Name Accounting Standards Codification
-Section 50
-Paragraph 3B
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147479319/326-20-50-3B

Reference 3: http://www.xbrl.org/2003/role/disclosureRef
-Topic 326
-SubTopic 20
-Name Accounting Standards Codification
-Section 50
-Paragraph 5
-Subparagraph (b)
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147479319/326-20-50-5

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- Definition

Amount of mortgage loan within investment in mortgage loan on real estate by entity with substantial portion of business acquiring and holding investment real estate or interest in real estate, written down.

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Topic 948
-SubTopic 310
-Name Accounting Standards Codification
-Section S99
-Paragraph 1
-Subparagraph (SX 210.12-29(Column G)(Footnote 7))
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147479628/948-310-S99-1

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