Stockholders' Equity - Additional Information (Detail) - USD ($) $ / shares in Units, $ in Thousands |
12 Months Ended | |||
|---|---|---|---|---|
Jan. 28, 2015 |
Dec. 31, 2015 |
Dec. 31, 2014 |
Dec. 31, 2016 |
|
| Proceeds from offering, net of commissions and underwriting discounts | $ 130,044 | $ 102,672 | ||
| Payments of public offering costs | $ 473 | $ 2,312 | ||
| Preferred stock, shares authorized | 5,000,000 | 5,000,000 | ||
| Preferred stock, par value | $ 0.001 | $ 0.001 | ||
| Common stock, shares authorized | 115,000,000 | 115,000,000 | ||
| Common stock, par value | $ 0.001 | $ 0.001 | ||
| Follow-on Offering [Member] | ||||
| Common stock issued | 3,942,200 | |||
| Common stock issued price per share | $ 35.00 | |||
| Proceeds from offering, net of commissions and underwriting discounts | $ 130,000 | |||
| Payments of public offering costs | $ 500 | |||