Residential Consumer Loans - Schedule of Characteristics of Residential Consumer Loans Held-for-Investment (Details) - Held-for-investment at fair value - Securitized Loans - USD ($) $ in Thousands	Mar. 31, 2026	Dec. 31, 2025
SEC Schedule, 12-29, Real Estate Companies, Investment in Mortgage Loans on Real Estate [Line Items]
UPB	$ 18,439,925	$ 15,048,820
Average loan balance (UPB)	885	915
Fair value of loans	$ 18,236,463	$ 14,843,747
Weighted average coupon	5.77%	5.68%
UPB of loans in foreclosure	$ 12,849	$ 16,709
Average foreclosure balance (UPB)	714	726
Financing Receivables, Equal to Greater than 90 Days Past Due
SEC Schedule, 12-29, Real Estate Companies, Investment in Mortgage Loans on Real Estate [Line Items]
Unpaid principal balance of loans with 90+ day delinquencies	40,864	42,872
Average 90+ days delinquent balance (UPB)	$ 801	$ 766

Fair Value, Option, Loans Held As Assets, Aggregate Amount In Foreclosure

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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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This item represents the aggregate fair value of loans held as assets that are 90 days or more past due for which the fair value option has been elected.

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For loans held as assets for which the fair value option has been elected, this item represents the difference between the aggregate fair value and the aggregate unpaid principal balance of those loans that are 90 days or more past due.

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Amortized cost, after allowance for credit loss, of financing receivable. Excludes financing receivable covered under loss sharing agreement and net investment in lease.

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This is the sum of principal amount outstanding for both securitized and unsecuritized loans of all types.

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