Weighted Average Shares Outstanding - Summary of Weighted Average Number of 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 shares outstanding	23,901	23,819	23,883	23,800
Plus: Dilutive effect of ISOs	62	105	62	105
Plus: Dilutive effect of Restricted grants	353	49	353	49
Diluted shares outstanding	24,316	23,973	24,298	23,954