ALLOWANCE FOR CREDIT LOSSES AND CREDIT QUALITY INFORMATION - Narrative (Details) $ in Thousands	3 Months Ended		9 Months Ended
	Sep. 30, 2026 USD ($) loan	Sep. 30, 2025 USD ($)	Sep. 30, 2026 USD ($) loan	Sep. 30, 2025 USD ($)	Jun. 30, 2026 USD ($)	Dec. 31, 2025 USD ($) loan	Jun. 30, 2025 USD ($)	Dec. 31, 2024 USD ($)
Accounts, Notes, Loans and Financing Receivable [Line Items]
Loan workout and other credit costs	$ 3,150	$ 1,802	$ 7,411	$ 3,671
Allowance for credit losses related to other accounts receivable	2,639	2,268	2,639	2,268	$ 2,767	$ 2,848	$ 2,811	$ 0
Various Modifications
Accounts, Notes, Loans and Financing Receivable [Line Items]
Unused commitments to extend credit	$ 15,300		$ 15,300			$ 6,400
Residential
Accounts, Notes, Loans and Financing Receivable [Line Items]
Number of loans in the process of foreclosure \| loan	27		27			29
Mortgage loans in process of foreclosure, amount	$ 5,300		$ 5,300			$ 6,200
Commercial
Accounts, Notes, Loans and Financing Receivable [Line Items]
Number of loans in the process of foreclosure \| loan	33		33			37
Mortgage loans in process of foreclosure, amount	$ 28,200		$ 28,200			$ 36,400
Residential and Consumer Loans
Accounts, Notes, Loans and Financing Receivable [Line Items]
Loan workout and other credit costs	$ 2,500	$ 1,100	$ 5,600	$ 3,300
Impairment loans, charge off period			90 days