Fair Value Measurement - Schedule of Rollforward of Level 3 Assets (Details) - Fair Value, Inputs, Level 3 - USD ($) $ in Thousands			3 Months Ended	6 Months Ended
Apr. 01, 2026	Mar. 31, 2026	Jun. 30, 2026	Jun. 30, 2025	Jun. 30, 2026	Jun. 30, 2025
Loans (at fair value)
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation, Calculation [Roll Forward]
Fair value, beginning balance	$ 1,014,089		$ 1,014,089	$ 814,677	$ 984,552	$ 806,304
Reclassification of loans			0		0
Purchases and originations of loans			1,152,609	929,170	1,963,730	1,649,707
Sale of loans			(941,051)	(566,077)	(1,562,524)	(1,139,391)
Purchase of loans for immediate resale			2,623,069	1,933,901	4,714,014	2,708,533
Immediate resale of loans			(2,623,069)	(1,933,901)	(4,714,014)	(2,708,533)
Repayments received			(142,656)	(127,063)	(268,788)	(233,012)
Charge-offs and changes in fair value recorded in earnings			(30,335)	(42,804)	(76,762)	(83,252)
Other changes			11,583	11,601	24,031	19,148
Fair value, ending balance		$ 1,014,089	1,064,239	1,019,504	1,064,239	1,019,504
Loans Held-for- Sale
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation, Calculation [Roll Forward]
Fair value, beginning balance	723,855		723,855	347,749	393,159	405,812
Reclassification of loans	(7,800)	314,000	(7,810)		306,159
Purchases and originations of loans			973,759	701,155	1,346,618	1,271,809
Sale of loans			(825,683)	(548,007)	(1,127,583)	(1,119,703)
Purchase of loans for immediate resale			2,623,069	1,933,901	4,714,014	2,708,533
Immediate resale of loans			(2,623,069)	(1,933,901)	(4,714,014)	(2,708,533)
Repayments received			(66,826)	(46,398)	(109,306)	(86,302)
Charge-offs and changes in fair value recorded in earnings			(13,743)	(8,961)	(25,627)	(24,683)
Other changes			3,602	249	3,734	(1,146)
Fair value, ending balance		723,855	787,154	445,787	787,154	445,787
Loans Held-for-Investment
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation, Calculation [Roll Forward]
Fair value, beginning balance	245,378		245,378	378,012	537,631	297,543
Reclassification of loans			7,810		(306,159)
Purchases and originations of loans			178,850	228,015	617,112	377,898
Sale of loans			(115,368)	(18,070)	(434,941)	(19,688)
Purchase of loans for immediate resale			0	0	0	0
Immediate resale of loans			0	0	0	0
Repayments received			(68,719)	(71,013)	(144,340)	(126,778)
Charge-offs and changes in fair value recorded in earnings			(15,174)	(30,429)	(48,842)	(51,402)
Other changes			7,981	11,352	20,297	20,294
Fair value, ending balance		245,378	240,758	497,867	240,758	497,867
Loans Held in Consolidated Securitization
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation, Calculation [Roll Forward]
Fair value, beginning balance	$ 44,856		44,856	88,916	53,762	102,949
Reclassification of loans			0		0
Purchases and originations of loans			0	0	0	0
Sale of loans			0	0	0	0
Purchase of loans for immediate resale			0	0	0	0
Immediate resale of loans			0	0	0	0
Repayments received			(7,111)	(9,652)	(15,142)	(19,932)
Charge-offs and changes in fair value recorded in earnings			(1,418)	(3,414)	(2,293)	(7,167)
Other changes			0	0	0	0
Fair value, ending balance		$ 44,856	$ 36,327	$ 75,850	$ 36,327	$ 75,850

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, Reclassification Of Loans

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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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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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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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