Net Income Per Common Share - Summary of Basic and Diluted Weighted Average Common Shares (Detail) In Thousands, unless otherwise specified	3 Months Ended		9 Months Ended
	Sep. 30, 2013	Sep. 30, 2012	Sep. 30, 2013	Sep. 30, 2012
Earnings Per Share [Abstract]
Basic weighted average common shares outstanding	20,117	22,398	21,226	22,573
Weighted average common equivalent shares	548	460	464	445
Diluted weighted average common shares outstanding	20,665	22,858	21,690	23,018
Options excluded from diluted weighted average share calculation as effect would have been anti-dilutive	608	967	700	644