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, 2022	Jun. 30, 2021	Jun. 30, 2022	Jun. 30, 2021
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation, Calculation [Roll Forward]
Balance at beginning of period	$ 4,956,772	$ 1,207,997	$ 4,222,584	$ 1,216,902
Purchases and originations	674,202	837,859	1,788,245	837,859
Draws	82,482	423	143,822	423
Changes in fair value recorded in Net gain on residential whole loans measured at fair value through earnings	(158,507)	6,226	(381,919)	38,313
Repayments	(280,662)	(38,932)	(482,747)	(64,502)
Sales and repurchases	(8,949)	430	(10,496)	430
Transfer to REO	(13,290)	(10,423)	(27,441)	(25,845)
Balance at end of period	5,252,048	2,003,580	5,252,048	2,003,580
Unsettled residential whole loans	$ 28,900	$ 131,300	$ 28,900	$ 131,300

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

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- Definition

Unsettled Residential Whole Loans

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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
-Publisher FASB
-Name Accounting Standards Codification
-Topic 820
-SubTopic 10
-Section 50
-Paragraph 2
-Subparagraph (c)(1)
-URI https://asc.fasb.org/extlink&oid=126976982&loc=d3e19207-110258

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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
-Publisher FASB
-Name Accounting Standards Codification
-Topic 820
-SubTopic 10
-Section 50
-Paragraph 2
-Subparagraph (c)(2)
-URI https://asc.fasb.org/extlink&oid=126976982&loc=d3e19207-110258

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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

No definition available.

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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
-Publisher FASB
-Name Accounting Standards Codification
-Topic 820
-SubTopic 10
-Section 50
-Paragraph 2
-Subparagraph (c)
-URI https://asc.fasb.org/extlink&oid=126976982&loc=d3e19207-110258

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