Net Loss Per Share - Schedule of Computation of Basic and Diluted Net Loss Per Share (Details) - USD ($) $ / shares in Units, shares in Thousands, $ in Thousands |
12 Months Ended | ||
|---|---|---|---|
Dec. 31, 2015 |
Dec. 31, 2014 |
Dec. 31, 2013 |
|
| Earnings Per Share [Abstract] | |||
| Net loss | $ (64,911) | $ (48,429) | $ (25,056) |
| Weighted-average common shares outstanding | 81,914 | 70,837 | 58,540 |
| Net loss per share — basic and diluted (in dollars per share) | $ (0.79) | $ (0.68) | $ (0.43) |