INVESTMENTS (Gross Realized Gains and Losses on All Investments) (Detail) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2017	Dec. 31, 2016	Dec. 31, 2015
Investments [Abstract]
Gross realized gains from sales of investments available-for-sale	$ 0	$ 1,491	$ 0
Net gains or (losses) from calls of investments available-for-sale	32	440	18
Net gains or (losses) from calls of investments held-to-maturity	0	1	18
Gross realized gains from sales of equity securities	1,241	0	0
Net securities gains	$ 1,273	$ 1,932	$ 36