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	9 Months Ended
Sep. 30, 2024	Sep. 30, 2023	Sep. 30, 2024	Sep. 30, 2023
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation, Calculation [Roll Forward]
Balance at beginning of period	$ 7,719,191	$ 6,441,964	$ 7,455,729	$ 5,676,430
Purchases and originations	432,232	635,646	1,456,353	1,707,209
Draws	132,944	166,937	448,849	418,928
Changes in fair value recorded in Net gain/(loss) on residential whole loans measured at fair value through earnings	137,859	(129,661)	164,748	(131,856)
Repayments	(532,502)	(309,214)	(1,434,164)	(836,440)
Loan sales and repurchases	(235,582)	(2,243)	(409,420)	(3,720)
Transfer to REO	(35,310)	(10,007)	(63,263)	(37,129)
Balance at end of period	$ 7,618,832	$ 6,793,422	$ 7,618,832	$ 6,793,422

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

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

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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).

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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.

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

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