Stockholders' Equity - Schedule of Stock Option Activity (Detail) $ / shares in Units, shares in Thousands, $ in Thousands	6 Months Ended
	Jun. 30, 2016 USD ($) $ / shares shares
Disclosure Of Compensation Related Costs Sharebased Payments [Abstract]
Number of Shares, Outstanding at December 31, 2015 | shares	2,171
Number of Shares, Granted | shares	61
Number of Shares, Exercised | shares	(122)
Number of Shares, Forfeited | shares	(174)
Number of Shares, Outstanding at June 30, 2016 | shares	1,936
Number of Shares, Exercisable at June 30, 2016 | shares	1,066
Number of Shares, Vested and expected to vest at June 30, 2016 | shares	1,845
Weighted - Average Exercise Price Per Share, Outstanding, Beginning balance | $ / shares	$ 33.84
Weighted - Average Exercise Price Per Share, Granted | $ / shares	34.00
Weighted - Average Exercise Price Per Share, Exercised | $ / shares	30.57
Weighted - Average Exercise Price Per Share, Forfeited | $ / shares	35.80
Weighted - Average Exercise Price Per Share, Outstanding, Ending balance | $ / shares	33.88
Weighted - Average Exercise Price Per Share, Exercisable at June 30, 2016 | $ / shares	32.69
Weighted - Average Exercise Price Per Share, Vested and expected to vest at June 30, 2016 | $ / shares	$ 33.82
Weighted - Average Remaining Contractual Term, Outstanding at June 30, 2016	6 years 6 months 4 days
Weighted - Average Remaining Contractual Term, Exercisable at June 30, 2016	4 years 10 months 28 days
Weighted - Average Remaining Contractual Term, Vested and expected to vest at June 30, 2016	6 years 4 months 24 days
Aggregate Intrinsic Value, Outstanding at June 30, 2016 | $	$ 6,554
Aggregate Intrinsic Value, Exercisable at June 30, 2016 | $	4,729
Aggregate Intrinsic Value, Vested and expected to vest at June 30, 2016 | $	$ 6,345