|
Common Stock (Details 2) (USD $)
In Thousands, unless otherwise specified |
3 Months Ended | 6 Months Ended | ||
|---|---|---|---|---|
|
Jun. 30, 2012
|
Jun. 30, 2011
|
Jun. 30, 2012
|
Jun. 30, 2011
|
|
| Summary of share-based compensation expense | ||||
| Share-based compensation | $ 709 | $ 283 | $ 1,029 | $ 554 |
|
Research and development [Member]
|
||||
| Summary of share-based compensation expense | ||||
| Share-based compensation | 293 | 122 | 428 | 243 |
|
General and administrative [Member]
|
||||
| Summary of share-based compensation expense | ||||
| Share-based compensation | $ 416 | $ 161 | $ 601 | $ 311 |