Stockholders' Equity - Basic and Diluted Net Income Per Common Shares (Detail) (USD $) In Thousands, except Share data, unless otherwise specified	3 Months Ended
	Mar. 31, 2014	Mar. 31, 2013
Equity [Abstract]
Net income	$ 4,890	$ 6,925
Weighted average shares of common stock outstanding	21,638,198	21,688,153
Dilutive effect of restricted stock and RSUs	399,598	216,709
Weighted average shares of common stock and common stock equivalents	22,037,796	21,904,862
Basic	$ 0.23	$ 0.32
Diluted	$ 0.22	$ 0.32