ACCUMULATED OTHER COMPREHENSIVE INCOME (LOSS) - Changes in Accumulated Other Comprehensive Income (Details) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2021	Dec. 31, 2020	Dec. 31, 2019
AOCI Including Portion Attributable to Noncontrolling Interest, Net of Tax [Roll Forward]
Balance	$ 657,184	$ 598,100	$ 521,704
Other comprehensive income (loss) before reclassification	(11,203)	15,839
Amounts reclassified from accumulated other comprehensive income (loss)	(448)	(154)
Net current period other comprehensive income (loss)	(11,651)	15,685	18,250
Balance	704,906	657,184	598,100
Total
AOCI Including Portion Attributable to Noncontrolling Interest, Net of Tax [Roll Forward]
Balance	27,744	12,059
Balance	16,093	27,744	12,059
Unrealized Gains and (Losses) on Available-for-Sales Securities
AOCI Including Portion Attributable to Noncontrolling Interest, Net of Tax [Roll Forward]
Balance	29,182	13,607
Other comprehensive income (loss) before reclassification	(11,496)	15,917
Amounts reclassified from accumulated other comprehensive income (loss)	(630)	(342)
Net current period other comprehensive income (loss)	(12,126)	15,575
Balance	17,056	29,182	13,607
Defined Benefit Pension Items
AOCI Including Portion Attributable to Noncontrolling Interest, Net of Tax [Roll Forward]
Balance	(1,438)	(1,548)
Other comprehensive income (loss) before reclassification	293	(78)
Amounts reclassified from accumulated other comprehensive income (loss)	182	188
Net current period other comprehensive income (loss)	475	110
Balance	$ (963)	$ (1,438)	$ (1,548)