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Stockholders' Equity - Narrative (Details) $ / shares in Units, $ in Thousands |  |  |  | 1 Months Ended | 3 Months Ended | 10 Months Ended | 12 Months Ended |  |  |
--- | --- | --- | --- | --- | --- | --- | --- | --- | --- | ---
Sep. 16, 2015 USD ($) | Sep. 11, 2015 $ / shares shares | Aug. 06, 2014 USD ($) $ / shares shares | Jul. 31, 2014 shares | Nov. 30, 2013 $ / shares shares | Sep. 30, 2013 shares | Sep. 30, 2014 | Mar. 31, 2014 shares | Sep. 30, 2013 $ / shares shares | Oct. 31, 2013 USD ($) $ / shares | Dec. 31, 2015 USD ($) plan $ / shares shares | Dec. 31, 2014 USD ($) $ / shares shares | Dec. 31, 2013 USD ($) $ / shares shares | Jul. 22, 2015 shares | Jul. 21, 2015 shares | May. 06, 2014 shares
Share-based Compensation Arrangement by Share-based Payment Award [Line Items] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Common stock, number of shares authorized |  |  |  |  |  |  |  |  |  |  | 30,000,000 | 15,000,000 |  | 30,000,000 | 15,000,000 |
Issuance of common stock (in shares) |  | 1,500,000 | 1,175,000 |  |  |  |  |  |  |  |  |  |  |  |  |
Share price (in dollars per share) | $ / shares |  | $ 17.00 | $ 4.50 |  |  |  |  |  |  |  | $ 13.75 |  |  |  |  |
Proceeds from issuances of common stock, net | $ | $ 23,600 |  | $ 5,150 |  |  |  |  |  |  |  | $ 23,574 | $ 5,952 | $ 0 |  |  |
Additional shares purchased (in shares) |  |  | 176,250 |  |  |  |  |  |  |  |  |  |  |  |  |
Number of shares |  |  | 47,000 |  |  |  |  |  |  |  |  |  |  |  |  |
Warrant issuance of common stock sold |  |  | 4.00% |  |  |  |  |  |  |  |  |  |  |  |  |
Exercise price (in dollars per share) | $ / shares |  |  | $ 5.40 |  |  |  |  |  |  |  |  |  |  |  |  |
Percentage of public offering price |  |  | 120.00% |  |  |  |  |  |  |  |  |  |  |  |  |
Conversion price (in dollars per share) | $ / shares |  |  |  |  |  |  |  |  |  | $ 2.30 |  |  |  |  |  |
Debt conversion, converted instrument, number of shares issued |  |  |  |  |  |  |  | 3,323,913 |  |  |  |  |  |  |  |
Number of additional other equity-based plans | plan |  |  |  |  |  |  |  |  |  |  | 2 |  |  |  |  |
Vesting period |  |  |  |  |  |  |  |  |  |  | 10 years |  |  |  |  |
Unamortized stock compensation expense | $ |  |  |  |  |  |  |  |  |  |  | $ 992 | $ 387 |  |  |  |
Remaining weighted average life |  |  |  |  |  |  |  |  |  |  | 1 year 10 months 21 days | 2 years 7 months 6 days |  |  |  |
Intrinsic value of options exercised | $ |  |  |  |  |  |  |  |  |  |  | $ 485 |  |  |  |  |
Intrinsic value of options outstanding | $ |  |  |  |  |  |  |  |  |  |  | 4,200 |  |  |  |  |
Intrinsic value of options exercisable | $ |  |  |  |  |  |  |  |  |  |  | $ 2,300 |  |  |  |  |
2013 Plan |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Share-based Compensation Arrangement by Share-based Payment Award [Line Items] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Number of shares authorized |  |  |  |  |  | 500,000 |  |  | 500,000 |  |  |  |  |  |  |
Number of shares available for grant (in shares) |  |  |  |  |  |  |  |  |  |  | 465,535 |  |  |  |  |
Purchase price of common stock, percent |  |  |  |  |  | 85.00% |  |  |  |  |  |  |  |  |  |
Shares issued in the period (in shares) |  |  |  |  |  |  |  |  |  |  | 18,119 | 9,932 | 17,655 |  |  |
Employee severance |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Share-based Compensation Arrangement by Share-based Payment Award [Line Items] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Acceleration of vesting (in options) |  |  |  |  | 7,000 |  |  |  |  |  |  |  |  |  |  |
Grant price (in dollars per share) | $ / shares |  |  |  |  | $ 2.30 |  |  |  |  |  |  |  |  |  |  |
Expiration period |  |  |  |  | 1 year |  |  |  |  | 3 months |  |  |  |  |  |
Restricted stock |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Share-based Compensation Arrangement by Share-based Payment Award [Line Items] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Vesting period |  |  |  |  |  |  | 1 year |  |  |  |  |  |  |  |  |
Restricted shares granted (in shares) |  |  |  |  |  |  |  |  | 5,122 |  | 0 | 0 | 0 |  |  |
Number of restricted shares forfeited (in shares) |  |  |  |  |  |  |  |  |  |  | 0 | 2,439 | 1,463 |  |  |
Restricted stock, vested (in shares) |  |  |  | 1,220 |  |  |  |  |  |  |  | 35,869 | 5,592 |  |  |
Fair value of restricted shares (in dollars per share) | $ / shares |  |  |  |  |  |  |  |  | $ 4.10 |  |  | $ 0.00 | $ 0.00 |  |  |
Minimum | Employee severance |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Share-based Compensation Arrangement by Share-based Payment Award [Line Items] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Expiration period |  |  |  |  |  |  |  |  | 1 year |  |  |  |  |  |  |
Minimum | Employee stock option |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Share-based Compensation Arrangement by Share-based Payment Award [Line Items] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Vesting period |  |  |  |  |  |  |  |  |  |  | 1 year |  |  |  |  |
Maximum | Employee stock option |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Share-based Compensation Arrangement by Share-based Payment Award [Line Items] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Vesting period |  |  |  |  |  |  |  |  |  |  | 4 years |  |  |  |  |
2014 Plan |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Share-based Compensation Arrangement by Share-based Payment Award [Line Items] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Number of shares authorized |  |  |  |  |  |  |  |  |  |  |  |  |  | 600,000 |  | 600,000
Number of shares available for grant (in shares) |  |  |  |  |  |  |  |  |  |  | 795,169 |  |  |  |  |
Expiration period |  |  |  |  |  |  |  |  |  |  | 10 years |  |  |  |  |
2014 Plan | Minimum |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Share-based Compensation Arrangement by Share-based Payment Award [Line Items] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Vesting period |  |  |  |  |  |  |  |  |  |  | 3 years |  |  |  |  |
2014 Plan | Maximum |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Share-based Compensation Arrangement by Share-based Payment Award [Line Items] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Vesting period |  |  |  |  |  |  |  |  |  |  | 4 years |  |  |  |  |
Unsecured convertible notes |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Share-based Compensation Arrangement by Share-based Payment Award [Line Items] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Unsecured convertible notes | $ |  |  |  |  |  |  |  |  |  | $ 7,600 |  |  |  |  |  |
Shares sold by selling stockholders |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Share-based Compensation Arrangement by Share-based Payment Award [Line Items] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Issuance of common stock (in shares) |  | 1,500,000 |  |  |  |  |  |  |  |  |  |  |  |  |  |

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