Summary of Significant Accounting Policies - Summary of Components Used to Calculate Basic and Diluted Earnings Per Share (Detail) (USD $) In Thousands, except Share data, unless otherwise specified	12 Months Ended
	Dec. 31, 2013	Dec. 31, 2012	Dec. 31, 2011
Accounting Policies [Abstract]
Net income available to common shareholders	$ 18,280	$ 10,858	$ 17,852
Weighted average number of common shares outstanding	23,918	23,816	23,446
Effect of dilutive restricted grants	378		63
Effect of dilutive options	169	41	29
Weighted average number of common shares outstanding used to calculate diluted earnings per share	24,465	23,857	23,538