INVESTMENTS (Amortized Cost and Estimated Fair Values of Debt Securities Held-To-Maturity by Contractual Maturity) (Detail) - USD ($) $ in Thousands	Dec. 31, 2015	Dec. 31, 2014
Amortized Cost
Due in one year or less	$ 845	$ 1,690
Due after one year through five years	19,217	6,763
Due after five years through ten years	163,125	163,252
Due after ten years	25,078	48,268
Total debt securities held-to-maturity	208,265	219,973
Estimated Fair Value
Due in one year or less	853	1,694
Due after one year through five years	20,041	6,938
Due after five years through ten years	165,620	164,787
Due after ten years	25,190	48,841
Total debt securities held-to-maturity	$ 211,704	$ 222,260