FAIR VALUE - Rollforward of changes in fair value of loans (Details) - USD ($) $ in Thousands	3 Months Ended	9 Months Ended
Sep. 30, 2023	Sep. 30, 2022	Sep. 30, 2023	Sep. 30, 2022
Mortgage loans held for sale
Guarantee asset
Balance at beginning of period	$ 19,746	$ 26,202	$ 8,839	$ 30,620
Loans transferred from held for investment	66,586	82,372	217,774	377,631
Fair value changes	(163)	(556)	(35)	(975)
Sales	(74,064)	(95,053)	(214,467)	(394,261)
Settlements	0	(222)	(6)	(272)
Balance at end of period	12,105	12,743	12,105	12,743
Loans held for sale
Guarantee asset
Balance at beginning of period	0	0	1,965	0
Loans transferred from held for investment	0	0	39,221	0
Fair value changes	0	0	(20)	0
Sales	0	0	(40,761)	0
Settlements	0	0	(405)	0
Balance at end of period	0	0	0	0
Loan Held for Investment
Guarantee asset
Balance at beginning of period	17,523	21,477	23,321	0
Fair value changes	110	(105)	(547)	223
Settlements	(1,806)	(6,361)	(7,101)	(9,461)
Loans acquired	0	7,860	1,162	32,109
Net charge-offs	(363)	0	(1,371)	0
Balance at end of period	$ 15,464	$ 22,871	$ 15,464	$ 22,871

Fair Value, Measurement with Unobservable Inputs Reconciliation, Recurring Basis, Asset, Write-Off

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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.

+ Details

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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 issuances 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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- 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

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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

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.

+ 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
-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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