Subsequent Events - Additional Information (Detail) - USD ($) |
12 Months Ended | ||||
|---|---|---|---|---|---|
Jan. 31, 2017 |
Dec. 31, 2014 |
Jan. 23, 2017 |
Dec. 31, 2016 |
Dec. 31, 2015 |
|
| Subsequent Event [Line Items] | |||||
| Common stock, par value per share | |||||
| Net proceeds from stock offering | $ 12,500,000 | ||||
| Number of shares provided through sales agreement | 1,108,156 | ||||
| Subsequent Event [Member] | Cantor Fitzgerald & Co [Member] | |||||
| Subsequent Event [Line Items] | |||||
| Common stock, par value per share | |||||
| Net proceeds from stock offering | $ 2,608,000 | ||||
| Number of shares provided through sales agreement | 294,524 | ||||
| Subsequent Event [Member] | Cantor Fitzgerald & Co [Member] | Maximum [Member] | |||||
| Subsequent Event [Line Items] | |||||
| Aggregate offering price | $ 20,000,000 |