Net Income Per Common Share - Summary of Basic and Diluted Weighted Average Common Shares (Detail) - shares shares in Thousands	3 Months Ended		6 Months Ended
	Jun. 30, 2015	Jun. 30, 2014	Jun. 30, 2015	Jun. 30, 2014
Earnings Per Share [Abstract]
Basic weighted average common shares outstanding	18,007	18,757	18,033	19,184
Weighted average common equivalent shares	261	287	281	295
Diluted weighted average common shares outstanding	18,268	19,044	18,314	19,479
Options excluded from diluted weighted average share calculation as effect would have been anti-dilutive	1,012	602	852	582