ACCUMULATED OTHER COMPREHENSIVE INCOME (LOSS) - Reclassification Adjustments Out of Accumulated Other Comprehensive Income (Detail) - USD ($) $ in Thousands	3 Months Ended	6 Months Ended
Jun. 30, 2021	Jun. 30, 2020	Jun. 30, 2021	Jun. 30, 2020
Unrealized gains on investments available for sale, affected line items in the Statements of Income
Investment securities gains			$ 129	$ 381
Income before taxes	$ 71	$ 212	129	381
Tax expense	$ (18)	$ (55)	(33)	(97)
Net income			96	284
Amortization of defined benefit pension plan items Affected line item in the Statements of Income:
Recognized actuarial loss			(454)	(437)
Loss before taxes			(454)	(437)
Tax benefit			121	111
Net loss			$ (333)	$ (326)

Amount, before tax and adjustment, of unrealized gain (loss) on investment in debt security measured at fair value with change in fair value recognized in other comprehensive income (available-for-sale) and unrealized gain (loss) on investment in debt security measured at amortized cost (held-to-maturity) from transfer to available-for-sale.

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Amount before tax of reclassification adjustment from accumulated other comprehensive income for unrealized gain (loss) realized upon the sale of available-for-sale securities.

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Amount after tax of reclassification adjustment from accumulated other comprehensive income for unrealized gain (loss) realized upon the sale of available-for-sale securities.

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