| **Stock-based Compensation, Equity Grants, and Warrants - Stock Option Activity (Details) (USD $)In Thousands, except Per Share data, unless otherwise specified** | 12 Months Ended          |
|--------------------------------------------------------------------------------------------------------------------------------------------------------------------|--------------------------|
||
| **Number of Shares**                                                                                                                                               |                     |   |   |
| Outstanding at beginning of period (in shares)                                                                                                                     | 1,613                    | 1,363 |   |
| Granted (in shares)                                                                                                                                                | 830                      | 250 |   |
| Cancelled (in shares)                                                                                                                                              | (63)                     |   |   |
| Outstanding at end of period (in shares)                                                                                                                           | 2,380                    | 1,613 | 1,363 |
| **Weighted Average Exercise Price**                                                                                                                                |                     |   |   |
| Outstanding at beginning of period (in dollars per share)                                                                                                          | $ 1.15                   | $ 1.19 |   |
| Granted (in dollars per share)                                                                                                                                     | $ 1.52                   | $ 0.95 |   |
| Cancelled (in dollars per share)                                                                                                                                   | $ 1.40                   |   |   |
| Outstanding at end of period (in dollars per share)                                                                                                                | $ 1.40                   | $ 1.15 | $ 1.19 |
| **Share Based Compensation Arrangement by Share Based Payment, Award, Options Weighted Average Remaining Contractual Term [Abstract]**                             |                     |   |   |
| Outstanding                                                                                                                                                        | 7 years 9 months 18 days | 7 years 10 months 24 days | 8 years 7 months 6 days |
| **Share Based Compensation Arrangement by Share Based Payment, Award, Options Aggregate Intrinsic Value [Abstract]**                                               |                     |   |   |
| Outstanding at the beginning of period (in dollars)                                                                                                                | $ 388                    | $ 140 |   |
| Outstanding at the end of period (in dollars)                                                                                                                      | $ 1,589                  | $ 388 | $ 140 |

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| - Definition
The number of shares under options that were cancelled during the reporting period as a result of occurrence of a terminating event specified in contractual agreements pertaining to the stock option plan.
+ References
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| - Definition
Gross number of share options (or share units) granted during the period.
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| - Definition
Amount by which the current fair value of the underlying stock exceeds the exercise price of options outstanding.
+ References
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|-------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------|
| - Definition
Number of options outstanding, including both vested and non-vested options.
+ References
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| - Definition
Weighted average price at which grantees can acquire the shares reserved for issuance under the stock option plan.
+ References
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| - Definition
Weighted average remaining contractual term for option awards outstanding, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days.
+ References
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| - Definition
Weighted average price at which grantees could have acquired the underlying shares with respect to stock options that were terminated.
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| - Definition
Weighted average per share amount at which grantees can acquire shares of common stock by exercise of options.
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