Stock-based Compensation (Details) shares in Thousands |
12 Months Ended |
|---|---|
|
Dec. 31, 2017
shares
| |
| Available as of December 31, 2016 | 948 |
| Granted | (1,872) |
| Forfeited | 211 |
| Expired | 151 |
| Share pool increase | 5,400 |
| Available as of December 31, 2017 | 4,838 |
| X | ||||||||||
- Definition Number of shares under non-option equity instrument agreements for which rights to exercise lapsed. Reference 1: http://www.xbrl.org/2003/role/presentationRef
|
| X | ||||||||||
- Definition Number of shares under non-option equity instrument agreements that were cancelled as a result of occurrence of a terminating event. Reference 1: http://www.xbrl.org/2003/role/presentationRef
|
| X | ||||||||||
- Definition Increase (decrease) in the number of shares under non-option equity instrument agreements. Reference 1: http://www.xbrl.org/2003/role/presentationRef
|
| X | ||||||||||
- Definition The difference between the maximum number of shares (or other type of equity) authorized for issuance under the plan (including the effects of amendments and adjustments), and the sum of: 1) the number of shares (or other type of equity) already issued upon exercise of options or other equity-based awards under the plan; and 2) shares (or other type of equity) reserved for issuance on granting of outstanding awards, net of cancellations and forfeitures, if applicable. Reference 1: http://www.xbrl.org/2003/role/presentationRef
|
| X | ||||||||||
- Definition Number of share instruments newly issued under a share-based compensation plan. Reference 1: http://www.xbrl.org/2003/role/presentationRef
|