LOANS - Change in allowance for credit losses (Details) - USD ($) $ in Thousands	3 Months Ended	9 Months Ended
Sep. 30, 2025	Sep. 30, 2024	Sep. 30, 2025	Sep. 30, 2024
Changes in allowance for credit losses
Beginning balance	$ 1,751	$ 2,052	$ 1,804	$ 2,045
Charge-offs	(39)	(82)	(718)	(90)
Recoveries	2		7
Provision	80		701	15
Ending balance	1,794	1,970	1,794	1,970
Mortgage loans on real estate portfolio segment
Changes in allowance for credit losses
Beginning balance	1,213	1,107	1,071	1,218
Provision	51	(16)	193	(127)
Ending balance	1,264	1,091	1,264	1,091
Commercial and industrial loans segment
Changes in allowance for credit losses
Beginning balance	435	467	372	325
Charge-offs	(24)	(78)	(679)	(78)
Recoveries			2
Provision	(4)	(7)	712	135
Ending balance	407	382	407	382
Consumer loans segment
Changes in allowance for credit losses
Beginning balance	120	144	144	93
Charge-offs	(15)	(4)	(39)	(12)
Recoveries	2		5
Provision	(1)	37	(4)	96
Ending balance	106	177	106	177
Unallocated
Changes in allowance for credit losses
Beginning balance	(17)	334	217	409
Provision	34	(14)	(200)	(89)
Ending balance	$ 17	$ 320	$ 17	$ 320

Amount excluding accrued interest, of allowance for credit loss on financing receivable. Excludes net investment in lease.

Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef
-Topic 326
-SubTopic 20
-Name Accounting Standards Codification
-Section 45
-Paragraph 1
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147479344/326-20-45-1

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- Definition

Amount, excluding accrued interest, of increase in allowance for credit loss on financing receivable from recovery. Excludes net investment in lease.

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Topic 326
-SubTopic 20
-Name Accounting Standards Codification
-Section 50
-Paragraph 13
-Subparagraph (e)
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147479319/326-20-50-13

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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, excluding accrued interest, of decrease in allowance for credit loss on financing receivable from writeoff. Excludes net investment in lease.

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Topic 326
-SubTopic 20
-Name Accounting Standards Codification
-Section 50
-Paragraph 13
-Subparagraph (d)
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147479319/326-20-50-13

Reference 2: http://www.xbrl.org/2003/role/disclosureRef
-Topic 326
-SubTopic 20
-Name Accounting Standards Codification
-Section 50
-Paragraph 6
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147479319/326-20-50-6

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- Definition

Amount, excluding accrued interest, of credit loss expense (reversal of expense) on financing receivable. Excludes net investment in lease.

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Topic 326
-SubTopic 20
-Name Accounting Standards Codification
-Section 50
-Paragraph 13
-Subparagraph (b)
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147479319/326-20-50-13

Reference 2: http://www.xbrl.org/2003/role/disclosureRef
-Topic 220
-SubTopic 40
-Name Accounting Standards Codification
-Section 50
-Paragraph 22
-Subparagraph (a)
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147476148/220-40-50-22

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