INCOME TAXES - Schedule of Deferred Tax Assets and Liabilities (Details) - USD ($) $ in Thousands	Dec. 31, 2023	Dec. 31, 2022
Deferred tax assets:
Other than temporary impairment	$ 739	$ 752
Net unrealized losses on retirement plans	3,497	5,614
Net unrealized loss on available for sale securities	35,358	39,242
Loan loss provisions	9,772	10,054
Unfunded commitments	528	537
Deferred compensation	1,711	1,957
Compensated absences	783	709
Post-retirement benefits	1,218	1,051
Lease liability	1,463	1,572
Purchase accounting		114
Other	3,808	3,018
GROSS DEFERRED ASSETS	58,877	64,620
Deferred tax liabilities:
Depreciation	(350)	(660)
Mortgage servicing rights	(310)	(458)
Pensions	(1,458)	(1,120)
Right-of-use asset	(1,452)	(1,566)
Intangibles	(6,318)	(6,093)
FHLB stock dividends		(32)
Purchase accounting	(157)
Other	(4,732)	(4,118)
GROSS DEFERRED LIABILITIES	(14,777)	(14,047)
NET DEFERRED TAX ASSETS	$ 44,100	$ 50,573