Stockholders' Equity (Deficit)- Restrict Stock Unit Activity (Details) - Restricted Stock Units (RSUs) [Member] - $ / shares |
12 Months Ended | |
|---|---|---|
Dec. 31, 2015 |
Dec. 31, 2014 |
|
| Share-based Compensation Arrangement by Share-based Payment Award [Line Items] | ||
| Beginning Balance (in shares) | 1,398,893 | |
| Restricted stock units granted (in shares) | 6,507,250 | |
| Restricted stock units vested (in shares) | (295,468) | |
| Restricted stock units canceled and forfeited (in shares) | (925,557) | |
| Ending Balance (in shares) | 6,685,118 | |
| Share-based Compensation Arrangement by Share-based Payment Award, Options, Nonvested, Weighted Average Grant Date Fair Value [Abstract] | ||
| Balance (in dollars per share) | $ 7.63 | $ 11,060 |
| Restricted stock units granted (in dollars per share) | 7.24 | |
| Restricted stock units vested (in dollars per share) | 10,700 | |
| Restricted stock units canceled and forfeited (in dollars per share) | $ 9.06 |