RELATED PARTY TRANSACTIONS - Narrative (Details) - USD ($) $ in Thousands	12 Months Ended
Dec. 31, 2025	Dec. 31, 2024
Related Party Transactions [Line Items]
Deposit liabilities	$ 37,900	$ 43,100
Interest	47,308	53,018
Rent expense	1,000	1,000
Fee income	120,376	112,128
2 Rush Street, Schenectady, New York
Related Party Transactions [Line Items]
Monthly rent expense	9	9
Related Party \| Subordinated Notes
Related Party Transactions [Line Items]
Subordinated notes issued	3,500
Interest	139
Interest expense	151
Director \| 2 Rush Street, Schenectady, New York
Related Party Transactions [Line Items]
Rent expense	110	$ 110
Management \| Wealth management group fee income \| Operating Segments \| Trust Services
Related Party Transactions [Line Items]
Fee income	$ 300
Minimum
Related Party Transactions [Line Items]
Related party principal ownership threshold (percent)	10.00%

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