DERIVATIVE INSTRUMENTS AND HEDGING ACTIVITIES - Cumulative basis adjustment for fair value hedges (Details) - Designated as hedging instruments - USD ($) $ in Thousands	Sep. 30, 2023	Dec. 31, 2022
DERIVATIVE INSTRUMENTS AND HEDGING ACTIVITIES
Closed Portfolio Amount	$ 87,512	$ 0
Cumulative amount of fair value hedging adjustment included in the carrying amount of assets	132	0
Available-for-sale - Municipals
DERIVATIVE INSTRUMENTS AND HEDGING ACTIVITIES
Closed Portfolio Amount	51,041	0
Cumulative amount of fair value hedging adjustment included in the carrying amount of assets	100	0
Available-for-sale - MBS
DERIVATIVE INSTRUMENTS AND HEDGING ACTIVITIES
Closed Portfolio Amount	36,471	0
Cumulative amount of fair value hedging adjustment included in the carrying amount of assets	32	0
Interest rate swaps
DERIVATIVE INSTRUMENTS AND HEDGING ACTIVITIES
Notional amount	$ 50,000	$ 0

Nominal or face amount used to calculate payments on the derivative asset.

Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 815
-SubTopic 10
-Section 50
-Paragraph 1A
-Subparagraph (d)
-URI https://asc.fasb.org/extlink&oid=125515794&loc=SL5579245-113959

Reference 2: http://www.xbrl.org/2009/role/commonPracticeRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 815
-SubTopic 10
-Section 50
-Paragraph 1B
-URI https://asc.fasb.org/extlink&oid=125515794&loc=SL5580258-113959

Reference 3: http://www.xbrl.org/2009/role/commonPracticeRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 815
-SubTopic 10
-Section 50
-Paragraph 1A
-Subparagraph (b)
-URI https://asc.fasb.org/extlink&oid=125515794&loc=SL5579245-113959

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- Definition

Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table.

+ References

No definition available.

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- Definition

Amount of cumulative increase (decrease) in fair value of hedged asset in fair value hedge, attributable to hedged risk, in last-of-layer hedging relationship.

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 815
-SubTopic 10
-Section 50
-Paragraph 4EEE
-Subparagraph (c)
-URI https://asc.fasb.org/extlink&oid=125515794&loc=SL109999718-113959

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- Definition

Amortized cost of closed portfolio of prepayable financial asset, used to designate hedging relationship in which hedged item is last layer expected to be remaining at end of hedging relationship.

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 815
-SubTopic 10
-Section 50
-Paragraph 4EEE
-Subparagraph (a)
-URI https://asc.fasb.org/extlink&oid=125515794&loc=SL109999718-113959

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