Redeemable Convertible Preferred Stock - Additional Information (Detail) - USD ($) $ in Thousands |
12 Months Ended | |||
|---|---|---|---|---|
Dec. 31, 2015 |
Dec. 31, 2014 |
Dec. 31, 2013 |
Feb. 04, 2014 |
|
| Conversion of Stock [Line Items] | ||||
| Issuance of common stock | 20,594,575 | 17,786,867 | ||
| Adjustment to preferred stock warrant liability recorded in other income (expense) | $ (2,559) | $ (126) | ||
| Redeemable Convertible Preferred Stock [Member] | ||||
| Conversion of Stock [Line Items] | ||||
| Issuance of common stock | 10,589,434 | |||
| Series C Preferred Stock [Member] | ||||
| Conversion of Stock [Line Items] | ||||
| Fair value of preferred stock warrants | $ 2,300 | |||
| Adjustment to preferred stock warrant liability recorded in other income (expense) | $ 0 | $ (1,900) | ||