INVESTMENTS (Amortized Cost and Estimated Fair Values of investment securities Available-For-Sale by Contractual Maturity) (Detail) - USD ($) $ in Thousands	Dec. 31, 2015	Dec. 31, 2014
Amortized Cost
Due in one year or less	$ 301	$ 691
Due after one year through five years	157,710	47,900
Due after five years through ten years	168,136	332,841
Due after ten years	253,792	276,647
Total debt securities available for sale	579,939	658,079
Estimated Fair Value
Due in one year or less	306	714
Due after one year through five years	160,257	49,385
Due after five years through ten years	174,677	340,852
Due after ten years	255,586	280,535
Estimated Fair Value	$ 590,826	$ 671,486