Fair Value of Financial Instruments - Changes in Unrealized Gains (Losses) Included in Earnings for Level 3 Assets and Liabilities (Details) - USD ($) $ in Thousands	3 Months Ended	9 Months Ended
Sep. 30, 2023	Sep. 30, 2022	Sep. 30, 2023	Sep. 30, 2022
Assets
Fair Value, Asset, Recurring Basis, Still Held, Unrealized Gain (Loss), Statement of Income or Comprehensive Income [Extensible Enumeration]	Unrealized losses, net	Unrealized losses, net	Unrealized losses, net	Unrealized losses, net
Liabilities
Fair Value, Liability, Recurring Basis, Still Held, Unrealized Gain (Loss), Statement of Income or Comprehensive Income [Extensible Enumeration]	Unrealized losses, net	Unrealized losses, net	Unrealized losses, net	Unrealized losses, net
Level 3 \| Consolidated SLST \| VIE, Primary Beneficiary
Assets
Unrealized gains (losses)	$ (30,705)	$ (33,188)	$ (38,230)	$ (110,631)
Residential loans \| Level 3
Assets
Unrealized gains (losses)	(8,986)	(57,296)	(12,927)	(90,749)
Residential Loans Held in Securitization Trusts \| Level 3
Assets
Unrealized gains (losses)	(15,178)	(66,697)	4,698	(150,664)
Preferred Equity and Mezzanine Loan Investments \| Level 3
Assets
Unrealized gains (losses)	(17)	(2,490)	762	(2,117)
Equity investments \| Level 3
Assets
Unrealized gains (losses)	(1,105)	(6,387)	(5,027)	(4,581)
Equity investments in disposal group held for sale \| Level 3
Assets
Unrealized gains (losses)	(2,622)	(1,054)	(3,937)	(504)
Collateralized Debt Obligations \| Level 3 \| Consolidated SLST \| VIE, Primary Beneficiary
Liabilities
Unrealized gains (losses)	$ 21,380	$ 25,263	$ 18,876	$ 83,151

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Indicates line item in statement in which net income is reported that includes unrealized gain (loss) from asset measured at fair value using unobservable input (level 3) and still held.

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Topic 820
-SubTopic 10
-Name Accounting Standards Codification
-Section 50
-Paragraph 2
-Subparagraph (d)
-Publisher FASB
-URI https://asc.fasb.org//1943274/2147482106/820-10-50-2

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+ References

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