Use of Special Purpose Entities and Variable Interest Entities - Narrative (Details) - USD ($) $ in Thousands	3 Months Ended	12 Months Ended
Mar. 31, 2025	Mar. 31, 2024	Dec. 31, 2024
Variable Interest Entity [Line Items]
Primary beneficiary, maximum loss exposure, amount	$ 18,400
Total residential whole loans	8,800,000		$ 8,800,000
Asset-backed Securities, Securitized Loans and Receivables
Variable Interest Entity [Line Items]
Proceeds from issuance of debt	8,857,447		8,574,069
Residential whole loans transferred to consolidated VIEs	7,000,000		6,900,000
Securitized debt	5,900,000		5,800,000
Asset-backed Securities, Securitized Loans and Receivables \| Other Assets
Variable Interest Entity [Line Items]
Real estate owned at fair value	30,700		$ 26,900
Asset-backed Securities, Securitized Loans and Receivables \| Senior Bonds
Variable Interest Entity [Line Items]
Proceeds from issuance of debt	283,400	$ 160,000
Proceed from debt net of offering expenses and underwriting discount	$ 283,400	$ 160,000

Loans, Including Fair Value Loans, Credit Impaired Loans And Other Loans At Carrying Value

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- Definition

Real Estate Owned At Fair Value

+ References

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- Definition

Residential Whole Loans, At Fair Value And Carrying Value

+ References

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- Definition

Secured financing other than securities sold under agreements to repurchase and securities loaned.

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- Definition

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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.

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Amount of maximum exposure to loss from involvement with consolidated variable interest entity (VIE).

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