Fully Vested Stock Options and Stock Options Expected to Vest (Detail) - USD ($) $ / shares in Units, shares in Thousands, $ in Thousands |
6 Months Ended | |
|---|---|---|
Jun. 30, 2017 |
Dec. 31, 2016 |
|
| Number of Shares | ||
| Outstanding | 3,386 | 3,292 |
| Exercisable | 2,568 | |
| Weighted Average Exercise Price | ||
| Outstanding | $ 32.55 | $ 32.06 |
| Exercisable | $ 32.87 | |
| Weighted Average Remaining Contractual Term (In years) | ||
| Outstanding | 6 years 7 months 10 days | |
| Exercisable | 5 years 10 months 14 days | |
| Aggregate Intrinsic Values | ||
| Outstanding | $ 3,945 | |
| Exercisable | $ 2,813 |