Annual report pursuant to Section 13 and 15(d)

Stock-based Expense - Outstanding Stock Options, Vested and Expected to Vest, Non-Vested and Stock Options Currently Exercisable (Detail)

v3.6.0.2
Stock-based Expense - Outstanding Stock Options, Vested and Expected to Vest, Non-Vested and Stock Options Currently Exercisable (Detail) - USD ($)
$ / shares in Units, $ in Thousands
12 Months Ended
Dec. 31, 2016
Dec. 31, 2015
Disclosure of Compensation Related Costs, Share-based Payments [Abstract]    
Number of options, options fully vested and expected to vest 3,606,462 5,795,711
Weighted average remaining contractual life (in years), options fully vested and expected to vest 6 years 6 months 7 years 6 months
Weighted average exercise price, options fully vested and expected to vest (in dollars per share) $ 19.58 $ 19.43
Aggregate intrinsic value, options fully vested and expected to vest $ 37,581 $ 21,080
Number of shares options, options exercisable 2,477,474 2,843,655
Weighted average remaining contractual life (in years), options exercisable 5 years 10 months 24 days 6 years 4 months 24 days
Weighted average exercise price, options exercisable (in dollars per share) $ 19.24 $ 18.67
Aggregate intrinsic value, options exercisable $ 26,659 $ 13,316