Fair Value Measurement - Schedule of Rollforward of Level 3 Assets (Details) - Fair Value, Inputs, Level 3 - USD ($) $ in Thousands	3 Months Ended
Mar. 31, 2026	Mar. 31, 2025
Loans (at fair value)
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation, Calculation [Roll Forward]
Fair value, beginning balance	$ 984,552	$ 806,304
Reclassification of loans	0
Purchases and originations of loans	811,121	720,537
Sale of loans	(621,473)	(573,314)
Purchase of loans for immediate resale	2,090,945	774,632
Immediate resale of loans	(2,090,945)	(774,632)
Repayments received	(126,132)	(105,949)
Charge-offs and changes in fair value recorded in earnings	(46,427)	(40,448)
Other changes	12,448	7,547
Fair value, ending balance	1,014,089	814,677
Loans Held-for- Sale
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation, Calculation [Roll Forward]
Fair value, beginning balance	393,159	405,812
Reclassification of loans	313,969
Purchases and originations of loans	372,859	570,654
Sale of loans	(301,900)	(571,696)
Purchase of loans for immediate resale	2,090,945	774,632
Immediate resale of loans	(2,090,945)	(774,632)
Repayments received	(42,480)	(39,904)
Charge-offs and changes in fair value recorded in earnings	(11,884)	(15,722)
Other changes	132	(1,395)
Fair value, ending balance	723,855	347,749
Loans Held-for-Investment
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation, Calculation [Roll Forward]
Fair value, beginning balance	537,631	297,543
Reclassification of loans	(313,969)
Purchases and originations of loans	438,262	149,883
Sale of loans	(319,573)	(1,618)
Purchase of loans for immediate resale	0	0
Immediate resale of loans	0	0
Repayments received	(75,621)	(55,765)
Charge-offs and changes in fair value recorded in earnings	(33,668)	(20,973)
Other changes	12,316	8,942
Fair value, ending balance	245,378	378,012
Loans Held in Consolidated Securitization
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation, Calculation [Roll Forward]
Fair value, beginning balance	53,762	102,949
Reclassification of loans	0
Purchases and originations of loans	0	0
Sale of loans	0	0
Purchase of loans for immediate resale	0	0
Immediate resale of loans	0	0
Repayments received	(8,031)	(10,280)
Charge-offs and changes in fair value recorded in earnings	(875)	(3,753)
Other changes	0	0
Fair value, ending balance	$ 44,856	$ 88,916

Fair Value, Measurement with Unobservable Inputs Reconciliation, Recurring Basis, Asset, Immediate Resale to Investors

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Fair Value, Measurement with Unobservable Inputs Reconciliation, Recurring Basis, Asset, Other Increase (Decrease)

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Fair Value, Measurement with Unobservable Inputs Reconciliation, Recurring Basis, Asset, Repayments Received

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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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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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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.

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