Fair Value Measurement - Loans Rollforward (Details) - Fair Value, Inputs, Level 3 - USD ($) $ in Thousands	3 Months Ended	6 Months Ended
Jun. 30, 2022	Jun. 30, 2021	Jun. 30, 2022	Jun. 30, 2021
Loans (at fair value)
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation, Calculation [Roll Forward]
Fair value, beginning balance	$ 597,981	$ 57,189	$ 252,477	$ 78,460
Reclassification of loans	0		0	0
Purchases of loans	696,451	49,672	1,139,641	80,859
Sale of loans	(583,918)	(20,432)	(634,682)	(66,901)
Purchase of loans for immediate resale	1,782,442	2,119,597	4,797,036	3,414,231
Immediate resale	(1,782,442)	(2,119,597)	(4,797,036)	(3,414,231)
Repayments received	(55,587)	(5,526)	(85,313)	(11,165)
Changes in fair value recorded in earnings	(32,806)	1,169	(52,317)	968
Other changes	1,642	239	3,957	90
Fair value, ending balance	623,763	82,311	623,763	82,311
Loan Held For Sale
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation, Calculation [Roll Forward]
Fair value, beginning balance	597,981	28,794	142,685	60,232
Reclassification of loans	(6,113)		103,679	(26)
Purchases of loans	682,575	20,071	1,125,765	38,311
Sale of loans	(583,918)	(20,432)	(634,682)	(66,901)
Purchase of loans for immediate resale	1,782,442	2,119,597	4,797,036	3,414,231
Immediate resale	(1,782,442)	(2,119,597)	(4,797,036)	(3,414,231)
Repayments received	(54,549)	(1,726)	(84,275)	(5,036)
Changes in fair value recorded in earnings	(32,319)	(5)	(51,830)	352
Other changes	1,662	39	3,977	(191)
Fair value, ending balance	605,319	26,741	605,319	26,741
Loans Held For Investment
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation, Calculation [Roll Forward]
Fair value, beginning balance	0	28,395	109,792	18,228
Reclassification of loans	6,113		(103,679)	26
Purchases of loans	13,876	29,601	13,876	42,548
Sale of loans	0	0	0	0
Purchase of loans for immediate resale	0	0	0	0
Immediate resale	0	0	0	0
Repayments received	(1,038)	(3,800)	(1,038)	(6,129)
Changes in fair value recorded in earnings	(487)	1,174	(487)	616
Other changes	(20)	200	(20)	281
Fair value, ending balance	$ 18,444	$ 55,570	$ 18,444	$ 55,570

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, Purchase Of Loans For Immediate Resale To Investors

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- Definition

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

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

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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.

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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
-Publisher FASB
-Name Accounting Standards Codification
-Topic 820
-SubTopic 10
-Section 50
-Paragraph 2
-Subparagraph (c)(1)
-URI https://asc.fasb.org/extlink&oid=126976982&loc=d3e19207-110258

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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
-Publisher FASB
-Name Accounting Standards Codification
-Topic 820
-SubTopic 10
-Section 50
-Paragraph 2
-Subparagraph (c)(2)
-URI https://asc.fasb.org/extlink&oid=126976982&loc=d3e19207-110258

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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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Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 820
-SubTopic 10
-Section 50
-Paragraph 2
-Subparagraph (c)
-URI https://asc.fasb.org/extlink&oid=126976982&loc=d3e19207-110258

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