Consolidated Balance Sheets (Parenthetical) - $ / shares |
Dec. 31, 2016 |
Dec. 31, 2015 |
|---|---|---|
| Statement Of Financial Position [Abstract] | ||
| Preferred stock, par value | $ 0.0001 | $ 0.0001 |
| Preferred stock, shares authorized | 5,000,000 | 5,000,000 |
| Preferred stock, shares issued | 0 | 0 |
| Preferred stock, shares outstanding | 0 | 0 |
| Common stock, par value | $ 0.0001 | $ 0.0001 |
| Common stock, shares authorized | 50,000,000 | 50,000,000 |
| Common stock, shares issued | 34,843,885 | 29,420,247 |
| Common stock, shares outstanding | 34,843,885 | 29,420,247 |