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Net (Loss) Income Per Share - Additional Information (Detail) - shares | Sep. 26, 2016 | Jun. 15, 2016 | Apr. 14, 2016 | Dec. 31, 2016 | Dec. 31, 2015
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Schedule of Net Income (Loss) Per Share [Line Items] |  |  |  |  |
Preferred stock issued pursuant to Private Placement |  |  | 4,630,145 |  |
Preferred stock issued pursuant to Subsequent Financing |  | 4,630,145 |  |  |
Preferred stock, shares outstanding |  |  |  | 0 | 0
Public Offering [Member] |  |  |  |  |
Schedule of Net Income (Loss) Per Share [Line Items] |  |  |  |  |
Common stock shares issued | 2,250,000 |  |  |  |

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