FAIR VALUE - Financial Assets and Liabilities at Dates Indicated that were Accounted for at Fair Value (Details) - USD ($) $ in Thousands	Mar. 31, 2024	Dec. 31, 2023
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Investments available-for-sale	$ 1,100,741	$ 1,102,681
Residential mortgage loans held for sale (at fair value)	16,627	10,836
Residential mortgage loans held for sale
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Residential mortgage loans held for sale (at fair value)	16,400	10,500
U.S. treasuries and government agencies
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Investments available-for-sale	92,236	96,927
State and municipal
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Investments available-for-sale	263,986	268,214
Mortgage-backed and asset-backed
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Investments available-for-sale	744,519	737,540
Fair Value, Recurring
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Investments available-for-sale	1,100,741	1,102,681
Total assets	1,135,126	1,129,384
Total liabilities	(17,758)	(15,867)
Fair Value, Recurring \| Residential mortgage loans held for sale
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Residential mortgage loans held for sale	16,627	10,836
Fair Value, Recurring \| U.S. treasuries and government agencies
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Investments available-for-sale	92,236	96,927
Fair Value, Recurring \| State and municipal
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Investments available-for-sale	263,986	268,214
Fair Value, Recurring \| Mortgage-backed and asset-backed
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Investments available-for-sale	744,519	737,540
Fair Value, Recurring \| Interest rate swap agreements
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Interest rate swap agreements	17,758	15,867
Interest rate swap agreements	(17,758)	(15,867)
Fair Value, Recurring \| Quoted Prices in Active Markets for Identical Assets (Level 1)
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Investments available-for-sale	0	0
Total assets	0	0
Total liabilities	0	0
Fair Value, Recurring \| Quoted Prices in Active Markets for Identical Assets (Level 1) \| Residential mortgage loans held for sale
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Residential mortgage loans held for sale	0	0
Fair Value, Recurring \| Quoted Prices in Active Markets for Identical Assets (Level 1) \| U.S. treasuries and government agencies
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Investments available-for-sale	0	0
Fair Value, Recurring \| Quoted Prices in Active Markets for Identical Assets (Level 1) \| State and municipal
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Investments available-for-sale	0	0
Fair Value, Recurring \| Quoted Prices in Active Markets for Identical Assets (Level 1) \| Mortgage-backed and asset-backed
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Investments available-for-sale	0	0
Fair Value, Recurring \| Quoted Prices in Active Markets for Identical Assets (Level 1) \| Interest rate swap agreements
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Interest rate swap agreements	0	0
Interest rate swap agreements	0	0
Fair Value, Recurring \| Significant Other Observable Inputs (Level 2)
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Investments available-for-sale	1,100,741	1,102,681
Total assets	1,135,126	1,129,384
Total liabilities	(17,758)	(15,867)
Fair Value, Recurring \| Significant Other Observable Inputs (Level 2) \| Residential mortgage loans held for sale
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Residential mortgage loans held for sale	16,627	10,836
Fair Value, Recurring \| Significant Other Observable Inputs (Level 2) \| U.S. treasuries and government agencies
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Investments available-for-sale	92,236	96,927
Fair Value, Recurring \| Significant Other Observable Inputs (Level 2) \| State and municipal
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Investments available-for-sale	263,986	268,214
Fair Value, Recurring \| Significant Other Observable Inputs (Level 2) \| Mortgage-backed and asset-backed
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Investments available-for-sale	744,519	737,540
Fair Value, Recurring \| Significant Other Observable Inputs (Level 2) \| Interest rate swap agreements
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Interest rate swap agreements	17,758	15,867
Interest rate swap agreements	(17,758)	(15,867)
Fair Value, Recurring \| Significant Unobservable Inputs (Level 3)
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Investments available-for-sale	0	0
Total assets	0	0
Total liabilities	0	0
Fair Value, Recurring \| Significant Unobservable Inputs (Level 3) \| Residential mortgage loans held for sale
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Residential mortgage loans held for sale	0	0
Fair Value, Recurring \| Significant Unobservable Inputs (Level 3) \| U.S. treasuries and government agencies
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Investments available-for-sale	0	0
Fair Value, Recurring \| Significant Unobservable Inputs (Level 3) \| State and municipal
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Investments available-for-sale	0	0
Fair Value, Recurring \| Significant Unobservable Inputs (Level 3) \| Mortgage-backed and asset-backed
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Investments available-for-sale	0	0
Fair Value, Recurring \| Significant Unobservable Inputs (Level 3) \| Interest rate swap agreements
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Interest rate swap agreements	0	0
Interest rate swap agreements	$ 0	$ 0

Fair value portion of probable future economic benefits obtained or controlled by an entity as a result of past transactions or events.

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Amount classified as assets attributable to disposal group held for sale or disposed of, expected to be disposed of within one year or the normal operating cycle, if longer.

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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).

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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.

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Fair value of financial and nonfinancial obligations.

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Fair value portion of loans held-for-sale including, but not limited to, mortgage loans and finance receivables.

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Fair value portion of other assets.

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Fair value portion of other liabilities.

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