FAIR VALUE - Summary of assets measured at fair value on recurring basis (Details) - USD ($) $ in Thousands	3 Months Ended	9 Months Ended
Sep. 30, 2023	Sep. 30, 2022	Sep. 30, 2023	Sep. 30, 2022
Guarantee asset
Fair Value, Asset, Recurring Basis, Unobservable Input Reconciliation, Gain (Loss), Statement of Income or Comprehensive Income [Extensible Enumeration]	Net income available for common shareholders	Net income available for common shareholders	Net income available for common shareholders	Net income available for common shareholders
Corporate bonds
Guarantee asset
Transfer to held-to-maturity				$ (6,215)
Significant Unobservable Inputs (Level 3) \| Fair Value, Recurring \| Corporate bonds
Guarantee asset
Balance at beginning of period	$ 0	$ 0	$ 0	2,113
Loans acquired				4,000
Balance at end of period	0	0	0	0
Significant Unobservable Inputs (Level 3) \| Fair Value, Recurring \| Loans Held at Fair Value
Guarantee asset
Balance at beginning of period	17,523	21,477	23,321
Loans acquired		7,867	1,162	32,599
Gains/(losses) in net income, net	110	(134)	(547)	(289)
Settlements	(2,169)	(6,339)	(8,472)	(9,439)
Balance at end of period	15,464	22,871	15,464	22,871
Significant Unobservable Inputs (Level 3) \| Fair Value, Recurring \| Forward commitments and FSC
Guarantee asset
Balance at beginning of period			0	(9)
Loans acquired		(11)	0	(2)
Balance at end of period	0	(11)	0	(11)
Significant Unobservable Inputs (Level 3) \| Fair Value, Recurring \| Guarantee Asset
Guarantee asset
Balance at beginning of period	166	174	143	237
Loans transferred from held for investment	6		20
Gains/(losses) in net income, net	(8)	(15)	11	(78)
Settlements	(6)		(16)
Balance at end of period	158	159	158	159
Significant Unobservable Inputs (Level 3) \| Fair Value, Recurring \| IRLC, net
Guarantee asset
Balance at beginning of period	453	990	229	1,473
Loans acquired	312	170	1,652	1,253
Loans transferred from held for investment	606	720	2,784	2,783
Gains/(losses) in net income, net	160	(302)	1,222	195
Balance at end of period	319	138	319	138
Significant Unobservable Inputs (Level 3) \| Fair Value, Recurring \| Equity Warrants
Guarantee asset
Balance at beginning of period	825	725	825	160
Loans acquired		102		344
Gains/(losses) in net income, net		0		323
Balance at end of period	$ 825	$ 827	$ 825	$ 827

Fair Value, Measurement with Unobservable Inputs Reconciliation, Recurring Basis, Asset, Unrealized Gains, Net

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.

+ 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 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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- Definition

Indicates line item in statement in which net income is reported that includes gain (loss) from asset measured at fair value using unobservable input (level 3).

+ References

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