COMPREHENSIVE INCOME - Changes of AOCI (Details) - USD ($) $ in Thousands	3 Months Ended		9 Months Ended
	Sep. 30, 2024	Sep. 30, 2023	Sep. 30, 2024	Sep. 30, 2023
Balance, beginning of period	$ 263,221	$ 248,117	$ 262,381	$ 249,325
Other comprehensive income (loss)	11,297	(11,753)	8,373	(9,948)
Balance, end of period	277,305	240,205	277,305	240,205
Unrealized (Losses) Gains on Securities
Balance, beginning of period	(41,710)	(48,536)	(38,878)	(50,370)
Other comprehensive income (loss)	11,314	(11,742)	8,482	(9,908)
Balance, end of period	(30,396)	(60,278)	(30,396)	(60,278)
Unfunded Retirement Obligations
Balance, beginning of period	349	463	441	492
Other comprehensive income (loss)	(17)	(11)	(109)	(40)
Balance, end of period	332	452	332	452
Accumulated Other Comprehensive (Loss) Income
Balance, beginning of period	(41,361)	(48,073)	(38,437)	(49,878)
Other comprehensive income (loss)	11,297	(11,753)	8,373	(9,948)
Balance, end of period	$ (30,064)	$ (59,826)	$ (30,064)	$ (59,826)