Common Stock (Details 2) (USD $)
In Thousands, unless otherwise specified |
3 Months Ended | 9 Months Ended | ||
---|---|---|---|---|
Sep. 30, 2012
|
Sep. 30, 2011
|
Sep. 30, 2012
|
Sep. 30, 2011
|
|
Summary of share-based compensation expense | ||||
Share-based compensation | $ 581 | $ 312 | $ 1,610 | $ 866 |
Research and development [Member]
|
||||
Summary of share-based compensation expense | ||||
Share-based compensation | 243 | 250 | 671 | 493 |
General and administrative [Member]
|
||||
Summary of share-based compensation expense | ||||
Share-based compensation | $ 338 | $ 62 | $ 939 | $ 373 |