Significant Accounting Policies - Schedule of Earnings Per Share (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]
Weighted average common shares outstanding-basic	38,686	40,327	38,729	40,501
Dilutive effect of common stock options and awards	202	235	183	222
Weighted average common shares outstanding-diluted	38,888	40,562	38,912	40,723