Condensed Consolidated Balance Sheets (Parenthetical) (unaudited) - $ / shares |
Sep. 30, 2016 |
Dec. 31, 2015 |
|---|---|---|
| Statement Of Financial Position [Abstract] | ||
| Undesignated preferred stock, par value | $ 0.001 | $ 0.001 |
| Undesignated preferred stock, shares authorized | 5,000,000 | 5,000,000 |
| Undesignated preferred stock, shares issued | 0 | 0 |
| Undesignated preferred stock, shares outstanding | 0 | 0 |
| Common stock, par value | $ 0.001 | $ 0.001 |
| Common stock, shares authorized | 100,000,000 | 100,000,000 |
| Common stock, shares issued | 22,627,711 | 17,608,615 |
| Common stock, shares outstanding | 22,627,711 | 17,608,615 |