Stock Plans - Schedule of Performance-Based Stock Options Activity (Detail) - USD ($) $ / shares in Units, $ in Thousands |
9 Months Ended | |
|---|---|---|
Sep. 30, 2018 |
Dec. 31, 2017 |
|
| Share-based Compensation Arrangement by Share-based Payment Award [Line Items] | ||
| Weighted-Average Aggregate Intrinsic Value | $ 3,240 | $ 44,974 |
| Weighted-Average Aggregate Intrinsic Value, Exercisable | $ 2,791 | |
| Performance-based Stock Options [Member] | 2018 Performance- Based Stock Incentive Plan [Member] | ||
| Share-based Compensation Arrangement by Share-based Payment Award [Line Items] | ||
| Options Granted | 3,167,325 | |
| Options, Outstanding, Ending Balance | 3,167,325 | |
| Weighted-Average Exercise Price, Options Granted | $ 21.25 | |
| Weighted-Average Exercise Price, Outstanding, Ending Balance | $ 21.25 | |
| Weighted-Average Remaining Contractual Term, Outstanding | 9 years 7 months 9 days |
| X | ||||||||||
- Definition Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table. No definition available.
|
| X | ||||||||||
- Definition Gross number of share options (or share units) granted during the period. No definition available.
|
| X | ||||||||||
- Definition Amount by which the current fair value of the underlying stock exceeds the exercise price of options outstanding. Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
|
| X | ||||||||||
- Definition Number of options outstanding, including both vested and non-vested options. Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
|
| X | ||||||||||
- Definition Weighted average price at which grantees can acquire the shares reserved for issuance under the stock option plan. Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
|
| X | ||||||||||
- Definition Weighted average per share amount at which grantees can acquire shares of common stock by exercise of options. No definition available.
|
| X | ||||||||||
- Definition Amount of difference between fair value of the underlying shares reserved for issuance and exercise price of vested portions of options outstanding and currently exercisable. Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
|
| X | ||||||||||
- Definition Weighted average remaining contractual term for option awards outstanding, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days. Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
|
| X | ||||||||||
- Details
|
| X | ||||||||||
- Details
|