Deposits - (Summary of Time Deposits Based Upon Contractual Maturity) (Detail) - USD ($) $ in Thousands	Dec. 31, 2015	Dec. 31, 2014
Deposits [Abstract]
Time Deposits - Three months or less	$ 214,724	$ 256,091
Time Deposits - Over 3 months through 6 months	200,771	255,301
Time Deposits - Over 6 months through 12 months	391,750	423,329
Time Deposits - Over 12 months through 24 months	271,353	321,073
Time Deposits - Over 24 months through 36 months	65,306	63,806
Time Deposits - Over 36 months through 48 months	36,955	24,467
Time Deposits - Over 48 months through 60 months	7,942	7,748
Time Deposits - Thereafter	5,082	5,236
Time Deposits, Total	$ 1,193,883	$ 1,357,051
Three months or less, Weighted Average Rate	0.53%	0.46%
Over 3 months through 6 months, Weighted Average Rate	0.52%	0.56%
Over 6 months through 12 months, Weighted Average Rate	0.68%	0.71%
Over 12 months through 24 months, Weighted Average Rate	0.81%	0.89%
Over 24 months through 36 months, Weighted Average Rate	1.25%	1.05%
Over 36 months through 48 months, Weighted Average Rate	1.39%	1.24%
Over 48 months through 60 months, Weighted Average Rate	1.08%	1.22%
Thereafter, Weighted Average Rate	1.48%	1.47%
Total time deposits, Weighted Average Rate	0.72%	0.71%