Fair Value Measurements - Schedule of Loans HFS at Fair Value Activity and Aggregate Fair Value of HFS Loans (Details) - USD ($) $ in Thousands	3 Months Ended	6 Months Ended
Jun. 30, 2026	Jun. 30, 2025	Jun. 30, 2026	Jun. 30, 2025	Dec. 31, 2025
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation, Calculation [Roll Forward]
Fair value unrealized gains (losses)	$ 3,900	$ 1,000	$ 27,200	$ 4,500
Fair value of loans held for investment	1,773,052		1,773,052		$ 1,762,396
Loans Held For Sale
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation, Calculation [Roll Forward]
Fair value at beginning of period	1,836,121	703,378	1,762,396	636,352
Originations	2,033,047	1,654,313	3,735,730	2,918,045
Sales	(1,815,442)	(1,217,166)	(3,199,716)	(2,314,095)
Principal payments	(214,534)	(101,107)	(400,955)	(169,662)
Realized charge-offs, net of recoveries, recorded in earnings	(18,494)	(4,663)	(30,560)	(11,367)
Fair value adjustments recorded in earnings	(47,646)	(26,587)	(93,843)	(51,105)
Fair value at end of period	1,773,052	$ 1,008,168	1,773,052	$ 1,008,168
Aggregate unpaid principal balance	1,833,689		1,833,689		1,795,818
Cumulative fair value adjustments	(60,637)		(60,637)		(33,422)
Fair value of loans held for investment	1,773,052		1,773,052		1,762,396
Loans Held For Sale \| 90 or more days past due
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation, Calculation [Roll Forward]
Aggregate unpaid principal balance	7,048		7,048		3,931
Cumulative fair value adjustments	(5,751)		(5,751)		(3,176)
Fair value of loans held for investment	$ 1,297		$ 1,297		$ 755

Fair Value, Measurement with Unobservable Inputs Reconciliation, Recurring Basis, Asset, Write-offs, Net of Recoveries

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Financing Receivable Aggregate Unpaid Principal Before Allowance For Credit Loss

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Financing Receivable, Cumulative Fair Value Adjustments

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Amount of unrealized gain (loss) recognized in income from asset measured at fair value on recurring basis using unobservable input (level 3) and still held.

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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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Amount of sale 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 settlement 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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Fair value portion of loans held-for-sale including, but not limited to, mortgage loans and finance receivables.

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