Stockholders' Equity and Stock Based Compensation - Basic and Diluted Net Income Per Common Shares (Detail) - USD ($) $ / shares in Units, $ in Thousands	3 Months Ended		6 Months Ended
	Jun. 30, 2016	Jun. 30, 2015	Jun. 30, 2016	Jun. 30, 2015
Equity [Abstract]
Net income	$ 3,451	$ 3,376	$ 6,895	$ 7,293
Weighted average shares of common stock outstanding (shares)	20,544,327	21,677,299	20,614,023	21,787,434
Dilutive effect of restricted stock and RSUs (shares)	160,879	58,530	217,717	56,157
Weighted average shares of common stock and common stock equivalents (shares)	20,705,206	21,735,829	20,831,740	21,843,591
Basic net income per common share (usd per share)	$ 0.17	$ 0.16	$ 0.33	$ 0.33
Diluted net income per common share (usd per share)	$ 0.17	$ 0.16	$ 0.33	$ 0.33