ACCUMULATED OTHER COMPREHENSIVE INCOME/ (LOSS) - Reclassification Adjustments Out of Accumulated Other Comprehensive Income (Detail) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2021	Dec. 31, 2020	Dec. 31, 2019
Unrealized gains/(losses) on investments available-for-sale: Affected line item in the Statements of Income:
Investment securities gains	$ 212	$ 467	$ 77
Income before taxes	212	467	77
Tax expense	(54)	(120)	(20)
Net income	158	347	57
Amortization of defined benefit pension plan items: Affected line item in the Statements of Income:
Recognized actuarial loss	(909)	(874)	(1,059)
Settlement charge (1)	(560)	0	0
Income before taxes	(1,469)	(874)	(1,059)
Tax benefit	376	223	277
Net loss	$ (1,093)	$ (651)	$ (782)