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LOANS AND ALLOWANCE FOR CREDIT LOSSES - Collateral Dependent (Details) - USD ($) $ in Thousands	Jun. 30, 2025	Mar. 31, 2025	Dec. 31, 2024	Jun. 30, 2024	Mar. 31, 2024	Dec. 31, 2023
Financing Receivable, Allowance for Credit Loss [Line Items]
Amortized Cost Basis	$ 4,981		$ 6,471
Related Allowance	22,665	$ 22,522	21,388	$ 21,031	$ 20,471	$ 22,517
Commercial and Industrial
Financing Receivable, Allowance for Credit Loss [Line Items]
Amortized Cost Basis	861		1,512
Related Allowance	4,524	5,153	4,520	4,894	4,516	5,055
Commercial Mortgages
Financing Receivable, Allowance for Credit Loss [Line Items]
Amortized Cost Basis	3,767		4,959
Related Allowance	12,714	12,089	11,214	10,530	10,367	12,026
Consumer Loans
Financing Receivable, Allowance for Credit Loss [Line Items]
Amortized Cost Basis	353		0
Related Allowance	2,830	$ 2,807	3,395	$ 3,501	$ 3,526	$ 3,242
Collateral Pledged
Financing Receivable, Allowance for Credit Loss [Line Items]
Amortized Cost Basis	4,172		5,089
Related Allowance	158		171
Commercial Real Estate And Business Assets \| Commercial and Industrial \| Commercial and industrial
Financing Receivable, Allowance for Credit Loss [Line Items]
Amortized Cost Basis	52		130
Related Allowance	0		65
Commercial Real Estate and Residential Real Estate \| Commercial Mortgages \| Owner occupied commercial real estate
Financing Receivable, Allowance for Credit Loss [Line Items]
Amortized Cost Basis	1,307		1,377
Related Allowance	9		15
Commercial Real Estate and Residential Real Estate \| Commercial Mortgages \| Non-owner occupied commercial real estate
Financing Receivable, Allowance for Credit Loss [Line Items]
Amortized Cost Basis	2,460		3,582
Related Allowance	149		91
Residential Real Estate \| Consumer Loans \| Home equity lines and loans
Financing Receivable, Allowance for Credit Loss [Line Items]
Amortized Cost Basis	353		0
Related Allowance	$ 0		$ 0