Fair Value of Financial Instruments - Level 3 Assets (Details) - Recurring basis - Level 3 - Residential whole loans, at fair value - USD ($) $ in Thousands	3 Months Ended	6 Months Ended
Jun. 30, 2023	Jun. 30, 2022	Jun. 30, 2023	Jun. 30, 2022
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation, Calculation [Roll Forward]
Balance at beginning of period	$ 6,013,378	$ 4,956,772	$ 5,676,430	$ 4,222,584
Purchases and originations	734,748	674,202	1,071,563	1,788,245
Draws	132,914	82,482	251,991	143,822
Changes in fair value recorded in Net gain/(loss) on residential whole loans measured at fair value through earnings	(129,797)	(158,507)	(2,193)	(381,919)
Repayments	(293,792)	(280,662)	(527,226)	(482,747)
Loan sales	(900)	(8,949)	(1,477)	(10,496)
Transfer to REO	(14,586)	(13,290)	(27,123)	(27,441)
Balance at end of period	$ 6,441,965	5,252,048	$ 6,441,965	5,252,048
Unsettled residential whole loans		$ 28,900		$ 28,900

Fair Value, Measurement With Unobservable Inputs Reconciliation, Recurring Basis, Asset, Originations And Draws

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- Definition

Fair Value, Measurement with Unobservable Inputs Reconciliation, Recurring Basis, Asset, Collection Of Principal

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- Definition

Fair Value, Measurement with Unobservable Inputs Reconciliation, Recurring Basis, Asset Value, Repurchases

+ References

No definition available.

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- Definition

Unsettled Residential Whole Loans

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- Definition

A roll forward is a reconciliation of a concept from the beginning of a period to the end of a period.

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- Definition

Amount of gain (loss) recognized in income from asset measured at fair value on recurring basis using unobservable input (level 3).

+ References

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

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- Definition

Amount of purchases of financial instrument classified as an asset measured using unobservable inputs that reflect the entity's own assumption about the assumptions market participants would use in pricing.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Name Accounting Standards Codification
-Topic 820
-SubTopic 10
-Section 50
-Paragraph 2
-Subparagraph (c)(2)
-Publisher FASB
-URI https://asc.fasb.org//1943274/2147482106/820-10-50-2

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- Definition

Amount of transfer of financial instrument classified as an asset into (out of) level 3 of the fair value hierarchy.

+ References

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- Definition

Fair value of financial instrument classified as an asset measured using unobservable inputs that reflect the entity's own assumption about the assumptions market participants would use in pricing.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Name Accounting Standards Codification
-Section 50
-Paragraph 2
-Subparagraph (c)
-SubTopic 10
-Topic 820
-Publisher FASB
-URI https://asc.fasb.org//1943274/2147482106/820-10-50-2

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