Residential Loans, at Fair Value - Narrative (Details) - USD ($)	12 Months Ended
Dec. 31, 2023	Dec. 31, 2022	Dec. 31, 2021
SEC Schedule, 12-29, Real Estate Companies, Investment in Mortgage Loans on Real Estate [Line Items]
Net realized gain (loss) on payoff and sale of mortgage loans	$ 4,600,000	$ 10,000,000	$ 18,800,000
Gain (loss) on sale of residential loans	(800,000)	0	$ 1,600,000
Principal outstanding	305,227,000
90 + \| Residential loans
SEC Schedule, 12-29, Real Estate Companies, Investment in Mortgage Loans on Real Estate [Line Items]
Principal outstanding	220,577,000	159,981,000
90 + \| VIE, Primary Beneficiary \| Residential loans \| Consolidated SLST
SEC Schedule, 12-29, Real Estate Companies, Investment in Mortgage Loans on Real Estate [Line Items]
Principal outstanding	$ 84,600,000	$ 143,200,000

Net Realized Gain (Loss) On Payoff And Sale Of Mortgage Loans

No definition available.

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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//1943274/2147479851/948-310-S99-1

+ Details

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- Definition

Amount of principal due on delinquent 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.

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Name Regulation S-X (SX)
-Number 210
-Section 12
-Subsection 29
-Paragraph Column H
-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 H))
-Publisher FASB
-URI https://asc.fasb.org//1943274/2147479851/948-310-S99-1

+ Details

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- Definition

The gains (losses) included in earnings that represent the difference between the sale price and the carrying value of loans made to finance real estate acquisitions. This element refers to the gain (loss) and not to the cash proceeds of the sale. This element is a noncash adjustment to net income when calculating net cash generated by operating activities using the indirect method.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Name Accounting Standards Codification
-Section 45
-Paragraph 28
-Subparagraph (b)
-SubTopic 10
-Topic 230
-Publisher FASB
-URI https://asc.fasb.org//1943274/2147482740/230-10-45-28

Reference 2: http://www.xbrl.org/2003/role/disclosureRef
-Name Accounting Standards Codification
-Section 45
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-Name Accounting Standards Codification
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-Paragraph 2
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-Topic 944
-Publisher FASB
-URI https://asc.fasb.org//1943274/2147479616/944-310-45-2

Reference 4: http://www.xbrl.org/2003/role/disclosureRef
-Name Accounting Standards Codification
-Section 50
-Paragraph 1
-SubTopic 310
-Topic 944
-Publisher FASB
-URI https://asc.fasb.org//1943274/2147479584/944-310-50-1

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