ACCUMULATED OTHER COMPREHENSIVE INCOME (LOSS) (Net Accumulated Other Comprehensive Income (Loss)) (Detail) - USD ($) $ in Thousands	3 Months Ended
	Mar. 31, 2020	Mar. 31, 2019
Accumulated Other Comprehensive Income (Loss) [Line Items]
Beginning Balance	$ (4,332)	$ (15,754)
Other comprehensive income before reclassification, net of tax	10,639	6,508
Reclassifications from accumulated other comprehensive income, net of tax	37	196
Total other comprehensive income	10,676	6,704
Ending Balance	6,344	(9,050)
Unrealized Gains (Losses) on Investments Available-for-Sale
Accumulated Other Comprehensive Income (Loss) [Line Items]
Beginning Balance	4,000	(6,630)
Other comprehensive income before reclassification, net of tax	10,639	6,508
Reclassifications from accumulated other comprehensive income, net of tax	(127)	0
Total other comprehensive income	10,512	6,508
Ending Balance	14,512	(122)
Defined Benefit Pension Plan
Accumulated Other Comprehensive Income (Loss) [Line Items]
Beginning Balance	(8,332)	(9,124)
Other comprehensive income before reclassification, net of tax	0	0
Reclassifications from accumulated other comprehensive income, net of tax	164	196
Total other comprehensive income	164	196
Ending Balance	$ (8,168)	$ (8,928)