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LOANS AND ALLOWANCE FOR CREDIT LOSSES - Summary of Total Loans (Details) - USD ($) $ in Thousands	6 Months Ended	12 Months Ended
	Jun. 30, 2025	Dec. 31, 2024	Mar. 31, 2025	Jun. 30, 2024	Mar. 31, 2024	Dec. 31, 2023
Accounts, Notes, Loans and Financing Receivable [Line Items]
Total loans	$ 3,152,664	$ 3,147,096
Allowance for credit losses	28,885	28,744	$ 28,614	$ 28,855	$ 28,355	$ 28,142
Net loans	3,123,779	3,118,352
Accrued interest receivable for loans	12,200	10,500
Tax exempt and other
Accounts, Notes, Loans and Financing Receivable [Line Items]
Total loans	35,409	44,275
Allowance for credit losses	110	128	112	110	113	119
Home equity
Accounts, Notes, Loans and Financing Receivable [Line Items]
Total loans	101,818	94,141
Allowance for credit losses	786	741	744	763	752	767
Total commercial loans \| Commercial construction
Accounts, Notes, Loans and Financing Receivable [Line Items]
Total loans	153,978	131,617
Allowance for credit losses	2,032	2,096	2,065	4,217	3,697	4,261
Total commercial real estate \| Commercial real estate owner occupied
Accounts, Notes, Loans and Financing Receivable [Line Items]
Total loans	313,709	302,074
Allowance for credit losses	2,823	2,794	2,830	2,620	3,081	2,863
Total commercial real estate \| Commercial real estate non-owner occupied
Accounts, Notes, Loans and Financing Receivable [Line Items]
Total loans	1,361,262	1,358,903
Allowance for credit losses	10,980	11,104	10,923	9,574	9,155	9,443
Total commercial and industrial \| Commercial and industrial
Accounts, Notes, Loans and Financing Receivable [Line Items]
Total loans	316,211	319,766
Allowance for credit losses	5,664	5,064	5,414	3,982	3,834	3,259
Total residential real estate \| Residential real estate
Accounts, Notes, Loans and Financing Receivable [Line Items]
Total loans	862,182	888,251
Allowance for credit losses	6,406	6,732	6,447	7,516	7,651	7,352
Total consumer \| Consumer other
Accounts, Notes, Loans and Financing Receivable [Line Items]
Total loans	8,095	8,069
Allowance for credit losses	$ 84	$ 85	$ 79	$ 73	$ 72	$ 78