Shares Outstanding Excluded from Calculation of Diluted Net Loss Per Share (Detail) - shares shares in Thousands |
3 Months Ended | 9 Months Ended | ||
|---|---|---|---|---|
Sep. 30, 2016 |
Sep. 30, 2015 |
Sep. 30, 2016 |
Sep. 30, 2015 |
|
| Antidilutive Securities Excluded From Computation Of Earnings Per Share [Line Items] | ||||
| Total potential dilutive shares | 8,418 | 9,878 | 8,418 | 9,878 |
| Convertible senior notes | ||||
| Antidilutive Securities Excluded From Computation Of Earnings Per Share [Line Items] | ||||
| Total potential dilutive shares | 4,646 | 4,646 | 4,646 | 4,646 |
| Common shares under options and awards | ||||
| Antidilutive Securities Excluded From Computation Of Earnings Per Share [Line Items] | ||||
| Total potential dilutive shares | 3,772 | 5,232 | 3,772 | 5,232 |