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LOANS AND ALLOWANCE FOR CREDIT LOSSES - Collateral Dependent (Details) - USD ($) $ in Thousands	Sep. 30, 2025	Jun. 30, 2025	Dec. 31, 2024	Sep. 30, 2024	Jun. 30, 2024	Dec. 31, 2023
Financing Receivable, Allowance for Credit Loss [Line Items]
Amortized Cost Basis	$ 4,126		$ 6,471
Related Allowance	23,645	$ 22,665	21,388	$ 21,441	$ 21,031	$ 22,517
Commercial and Industrial
Financing Receivable, Allowance for Credit Loss [Line Items]
Amortized Cost Basis	668		1,512
Related Allowance	4,577	4,524	4,520	4,896	4,894	5,055
Commercial Mortgages
Financing Receivable, Allowance for Credit Loss [Line Items]
Amortized Cost Basis	3,116		4,959
Related Allowance	13,738	12,714	11,214	10,762	10,530	12,026
Consumer Loans
Financing Receivable, Allowance for Credit Loss [Line Items]
Amortized Cost Basis	342		0
Related Allowance	2,697	$ 2,830	3,395	$ 3,565	$ 3,501	$ 3,242
Collateral Pledged
Financing Receivable, Allowance for Credit Loss [Line Items]
Amortized Cost Basis	3,522		5,089
Related Allowance	176		171
Commercial Real Estate And Business Assets \| Commercial and Industrial \| Commercial and industrial
Financing Receivable, Allowance for Credit Loss [Line Items]
Amortized Cost Basis	64		130
Related Allowance	12		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	658		1,377
Related Allowance	7		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	2,458		3,582
Related Allowance	157		91
Residential Real Estate \| Consumer Loans \| Home equity lines and loans
Financing Receivable, Allowance for Credit Loss [Line Items]
Amortized Cost Basis	342		0
Related Allowance	$ 0		$ 0