Fair Value Measurement - Loans Rollforward (Details) - Fair Value, Inputs, Level 3 - USD ($) $ in Thousands	3 Months Ended	6 Months Ended
Jun. 30, 2023	Jun. 30, 2022	Jun. 30, 2023	Jun. 30, 2022
Loans (at fair value)
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation, Calculation [Roll Forward]
Fair value, beginning balance	$ 982,229	$ 597,981	$ 1,010,421	$ 252,477
Reclassification of loans		0		0
Purchases of loans	490,151	696,451	657,967	1,139,641
Sale of loans	(550,860)	(583,918)	(618,392)	(634,682)
Purchase of loans for immediate resale	291,570	1,782,442	680,959	4,797,036
Immediate resale of loans	(291,570)	(1,782,442)	(680,959)	(4,797,036)
Repayments received	(69,885)	(55,587)	(152,258)	(85,313)
Changes in fair value recorded in earnings	(14,145)	(32,806)	(62,306)	(52,317)
Other changes	75	1,642	2,133	3,957
Fair value, ending balance	837,565	623,763	837,565	623,763
Loan Held For Sale
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation, Calculation [Roll Forward]
Fair value, beginning balance	839,482	597,981	882,810	142,685
Reclassification of loans		(6,113)		103,679
Purchases of loans	448,773	682,575	569,388	1,125,765
Sale of loans	(550,860)	(583,918)	(618,392)	(634,682)
Purchase of loans for immediate resale	291,570	1,782,442	680,959	4,797,036
Immediate resale of loans	(291,570)	(1,782,442)	(680,959)	(4,797,036)
Repayments received	(47,302)	(54,549)	(108,803)	(84,275)
Changes in fair value recorded in earnings	866	(32,319)	(34,564)	(51,830)
Other changes	(1,108)	1,662	(588)	3,977
Fair value, ending balance	689,851	605,319	689,851	605,319
Loans Held For Investment
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation, Calculation [Roll Forward]
Fair value, beginning balance	142,747	0	127,611	109,792
Reclassification of loans		6,113		(103,679)
Purchases of loans	41,378	13,876	88,579	13,876
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	(22,583)	(1,038)	(43,455)	(1,038)
Changes in fair value recorded in earnings	(15,011)	(487)	(27,742)	(487)
Other changes	1,183	(20)	2,721	(20)
Fair value, ending balance	$ 147,714	$ 18,444	$ 147,714	$ 18,444

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)

+ References

No definition available.

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Fair Value, Measurement with Unobservable Inputs Reconciliation, Recurring Basis, Asset, Purchase Of Loans For Immediate Resale To Investors

+ References

No definition available.

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- Definition

Fair Value, Measurement with Unobservable Inputs Reconciliation, Recurring Basis, Asset, Reclassification

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- Definition

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

+ References

No definition available.

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- Definition

A roll forward is a reconciliation of a concept from the beginning of a period to the end of a period.

+ References

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- Definition

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

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Topic 820
-SubTopic 10
-Name Accounting Standards Codification
-Section 50
-Paragraph 2
-Subparagraph (c)(1)
-Publisher FASB
-URI https://asc.fasb.org//1943274/2147482106/820-10-50-2

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- Definition

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.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Name Accounting Standards Codification
-Topic 820
-SubTopic 10
-Section 50
-Paragraph 2
-Subparagraph (c)(2)
-Publisher FASB
-URI https://asc.fasb.org//1943274/2147482106/820-10-50-2

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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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-Name Accounting Standards Codification
-Section 50
-Paragraph 2
-Subparagraph (c)
-SubTopic 10
-Topic 820
-Publisher FASB
-URI https://asc.fasb.org//1943274/2147482106/820-10-50-2

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