Share-Based Compensation - Schedule of Share-Based Compensation Expense (Detail) - USD ($) $ / shares in Units, shares in Thousands, $ in Thousands	12 Months Ended
	Dec. 31, 2016	Dec. 31, 2015	Dec. 31, 2014
Disclosure Of Compensation Related Costs Sharebased Payments [Abstract]
Pre-tax expense	$ 10,202	$ 7,895	$ 8,195	[1]
Tax effect	(3,846)	(3,000)	(3,114)
After tax expense	$ 6,356	$ 4,895	$ 5,081
Denominator for basic shares—Weighted average shares	36,580	37,457	38,705	[1]
Denominator for diluted shares—Adjusted weighted average shares and the effect of dilutive securities	36,918	37,457	39,130	[1]
Net expense per share—basic	$ 0.17	$ 0.13	$ 0.13
Net expense per share—diluted	$ 0.17	$ 0.13	$ 0.13

[1] Revised in 2015 for the impact of the changes in accounting principle related to inventory accounting.