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Capital Stock - Additional Information (Detail) - USD ($) $ / shares in Units, $ in Thousands |  | 12 Months Ended
--- | --- | ---
Sep. 29, 2016 | Dec. 31, 2016 | Dec. 31, 2015
Class of Stock [Line Items] |  |  |
Common stock, shares issued |  | 20,647,612 | 13,273,470
Common stock price per share |  | $ 0.01 | $ 0.01
Conversion of preferred stock in to common stock, preferred stock converted | 10,737,275 |  |
Proceeds from issuance of issuance of common stock, preferred stock and warrants, net of issuance costs | $ 27,600 | $ 27,630 |
Warrant expense |  | $ 3,100 | $ 11
Common stock, shares authorized |  | 100,000,000 | 100,000,000
Preferred stock, shares authorized |  | 30,000,000 |
Minimum threshold percentage of beneficial common stock interest | 4.99% |  |
Maximum threshold percentage of beneficial common stock interest on holder's discretion | 9.99% |  |
Convertible preferred stock, terms of conversion |  | The Series A Preferred Stock shall not be converted if, after giving effect to the conversion, the holder and its affiliated persons would own beneficially more than 4.99% of our common stock (subject to adjustment up to 9.99% solely at the holder's discretion upon 61 days' prior notice to us or, solely as to a holder, if such limitation is waived by such holder upon execution of the private placement agreement). |
Series A Preferred Stock [Member] |  |  |
Class of Stock [Line Items] |  |  |
Preferred stock, shares issued | 24,158.8693 |  |
Preferred stock par value | $ 0.01 |  |
Private Placement [Member] |  |  |
Class of Stock [Line Items] |  |  |
Gross proceeds from issuance of common stock, preferred stock and warrants | $ 30,000 |  |
Common stock, shares issued | 2,596,059 |  |
Common stock price per share | $ 2.25 |  |
Conversion of preferred stock in to common stock, preferred stock converted | 10,737,275 | 444.44 |
Class of Warrants or right to purchase common stock | 13,333,334 |  |
Class of Warrants or right to purchase common stock, exercise price | $ 2.25 | $ 2.25 |
Warrants granted to placement agent | 133,333 |  |
Proceeds from issuance of issuance of common stock, preferred stock and warrants, net of issuance costs | $ 27,600 |  |
Warrants granted to placement agent, exercise price | $ 2.25 |  |
Minimum percentage of outstanding common stock |  | 50.00% |
Warrants expiry period |  | 5 years |
Warrants exercisable period |  | 6 months |
Fair value of warrants |  | $ 30,700 |
Excess fair value of warrant liability |  | 400 |
Warrant expense |  | $ 3,100 |
Preferred stock par value |  | $ 0.01 |
Private Placement [Member] | Members of Board of Directors [Member] |  |  |
Class of Stock [Line Items] |  |  |
Common stock, shares issued |  | 283,046 |
Preferred stock, shares issued |  | 2,563.1439 |
Class of Warrants or right to purchase common stock |  | 1,422,221 |
Class of Warrants or right to purchase common stock, exercise price |  | $ 2.25 |
Private Placement [Member] | Series A Preferred Stock [Member] |  |  |
Class of Stock [Line Items] |  |  |
Preferred stock, shares issued | 24,158.8693 |  |
Conversion of preferred stock in to common stock, preferred stock converted | 444.44 |  |

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