Accounting Policies - Summary of Computation of Basic and Diluted Earnings Per Share (Detail) - USD ($) $ / shares in Units, $ in Thousands	3 Months Ended
	Mar. 31, 2016	Mar. 31, 2015
Basic earnings per share
Net income	$ 5,381	$ 5,358
Less: Preferred stock dividends	42	31
Net income available to common shareholders	$ 5,339	$ 5,327
Weighted average common shares outstanding	11,949,416	9,216,011
Basic Earnings Per Share	$ 0.45	$ 0.58
Diluted earnings per share
Net income available to common shareholders	$ 5,339	$ 5,327
Weighted average common shares outstanding	11,949,416	9,216,011
Effect of dilutive securities:
Warrants		321,652
Weighted average shares outstanding	12,008,484	9,609,506
Diluted Earnings Per Share	$ 0.44	$ 0.55
Restricted Stock [Member]
Effect of dilutive securities:
Effect of dilutive securities	21,033	30,510
Stock Options [Member]
Effect of dilutive securities:
Effect of dilutive securities	38,035	41,333