FAIR VALUES OF FINANCIAL INSTRUMENTS - Fair Value of Derivatives as of Measurement Date (Level 2 Inputs) (Details) - USD ($) $ in Thousands	Dec. 31, 2023	Dec. 31, 2022
Fair value measurement
Fair Value	$ 1,259,137	$ 1,330,481
U.S. Government agencies
Fair value measurement
Fair Value	91,440	98,473
Mortgage Backed Securities - residential
Fair value measurement
Fair Value	569,885	620,248
Mortgage Backed Securities - commercial
Fair value measurement
Fair Value	7,483	9,677
Collateralized mortgage obligations
Fair value measurement
Fair Value	180,829	203,485
State and municipal
Fair value measurement
Fair Value	370,811	360,153
Municipal taxable
Fair value measurement
Fair Value	34,285	32,515
U.S. Treasury
Fair value measurement
Fair Value	1,402	2,944
Collateralized debt obligations
Fair value measurement
Fair Value	3,002	2,986
Level 1
Fair value measurement
Fair Value	0	0
Level 2
Fair value measurement
Fair Value	1,254,955	1,325,950
Derivative Assets	2,878	2,838
Derivative Liabilities	(2,878)	(2,838)
Level 2 \| U.S. Government agencies
Fair value measurement
Fair Value	91,440	98,473
Level 2 \| Mortgage Backed Securities - residential
Fair value measurement
Fair Value	569,885	620,248
Level 2 \| Mortgage Backed Securities - commercial
Fair value measurement
Fair Value	7,483	9,677
Level 2 \| Collateralized mortgage obligations
Fair value measurement
Fair Value	180,829	203,485
Level 2 \| State and municipal
Fair value measurement
Fair Value	369,631	358,608
Level 2 \| Municipal taxable
Fair value measurement
Fair Value	34,285	32,515
Level 2 \| U.S. Treasury
Fair value measurement
Fair Value	1,402	2,944
Level 3
Fair value measurement
Fair Value	4,182	4,531
Level 3 \| State and municipal
Fair value measurement
Fair Value	1,180	1,545
Level 3 \| Collateralized debt obligations
Fair value measurement
Fair Value	$ 3,002	$ 2,986

Fair value, after the effects of master netting arrangements, of a financial asset or other contract with one or more underlying, notional amount or payment provision or both, and the contract can be net settled by means outside the contract or delivery of an asset. Includes assets not subject to a master netting arrangement and not elected to be offset.

No definition available.

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- Definition

Fair value, after the effects of master netting arrangements, of a financial liability or contract with one or more underlying, notional amount or payment provision or both, and the contract can be net settled by means outside the contract or delivery of an asset. Includes liabilities not subject to a master netting arrangement and not elected to be offset.

+ References

No definition available.

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- Definition

Amount excluding accrued interest, of investment in debt security measured at fair value with change in fair value recognized in other comprehensive income (available-for-sale).

+ References

Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef
-Topic 326
-SubTopic 30
-Name Accounting Standards Codification
-Section 45
-Paragraph 1
-Publisher FASB
-URI https://asc.fasb.org//1943274/2147479130/326-30-45-1

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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

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Topic 820
-SubTopic 10
-Name Accounting Standards Codification
-Section 50
-Paragraph 2
-Subparagraph (a)
-Publisher FASB
-URI https://asc.fasb.org//1943274/2147482106/820-10-50-2

Reference 2: http://www.xbrl.org/2003/role/disclosureRef
-Topic 820
-SubTopic 10
-Name Accounting Standards Codification
-Section 50
-Paragraph 2
-Subparagraph (b)
-Publisher FASB
-URI https://asc.fasb.org//1943274/2147482106/820-10-50-2

Reference 3: http://www.xbrl.org/2003/role/disclosureRef
-Topic 820
-SubTopic 10
-Name Accounting Standards Codification
-Section 50
-Paragraph 3
-Publisher FASB
-URI https://asc.fasb.org//1943274/2147482106/820-10-50-3

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