Fair Value Measurement - Loans Rollforward (Details) - Fair Value, Inputs, Level 3 - USD ($) $ in Thousands	3 Months Ended
Mar. 31, 2023	Mar. 31, 2022
Loans (at fair value)
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation, Calculation [Roll Forward]
Fair value, beginning balance	$ 1,010,421	$ 252,477
Reclassification of loans from HFI to HFS		0
Purchases of loans	167,816	443,190
Sale of loans	(67,532)	(50,764)
Purchase of loans for immediate resale	389,389	3,014,594
Immediate resale of loans	(389,389)	(3,014,594)
Repayments received	(82,373)	(29,726)
Changes in fair value recorded in earnings	(48,161)	(19,511)
Other changes	2,058	2,315
Fair value, ending balance	982,229	597,981
Loan Held For Sale
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation, Calculation [Roll Forward]
Fair value, beginning balance	882,810	142,685
Reclassification of loans from HFI to HFS		109,792
Purchases of loans	120,615	443,190
Sale of loans	(67,532)	(50,764)
Purchase of loans for immediate resale	389,389	3,014,594
Immediate resale of loans	(389,389)	(3,014,594)
Repayments received	(61,501)	(29,726)
Changes in fair value recorded in earnings	(35,430)	(19,511)
Other changes	520	2,315
Fair value, ending balance	839,482	597,981
Loans Held For Investment
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation, Calculation [Roll Forward]
Fair value, beginning balance	127,611	109,792
Reclassification of loans from HFI to HFS		(109,792)
Purchases of loans	47,201	0
Sale of loans	0	0
Purchase of loans for immediate resale	0	0
Immediate resale of loans	0	0
Repayments received	(20,872)	0
Changes in fair value recorded in earnings	(12,731)	0
Other changes	1,538	0
Fair value, ending balance	$ 142,747	$ 0

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

No definition available.

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- Definition

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

+ References

No definition available.

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- Definition

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

+ References

No definition available.

+ Details

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- Definition

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

+ References

No definition available.

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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

No definition available.

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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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- Definition

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.

+ References

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- Definition

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.

+ 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)
-URI https://asc.fasb.org/extlink&oid=126976982&loc=d3e19207-110258

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