ACQUISITIONS - Intangible asset, goodwill and acquisition related expenses (Details) - USD ($) $ in Thousands	3 Months Ended		6 Months Ended
	Jun. 30, 2023	Jun. 30, 2022	Jun. 30, 2023	Jun. 30, 2022	May 13, 2022
Identifiable Intangible Assets
Merger and acquisition integration related (recoveries) expenses	$ (1)	$ 3,960	$ 56	$ 4,259
Other Intangibles
Identifiable Intangible Assets
Intangible asset useful life (amortization period)	10 years		10 years
Elmira Savings Bank ("Elmira")
Identifiable Intangible Assets
Federal Home Loan Bank of New York borrowings					$ 17,600
Weighted-average rate					2.48%
Axiom | Core Deposit Intangibles
Identifiable Intangible Assets
Intangible asset useful life (amortization period)	8 years		8 years