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10. Stock-Based Compensation (Tables) | 12 Months Ended
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Dec. 31, 2019
Share-based Payment Arrangement, Noncash Expense [Abstract] |
Schedule of options granted under employee stock plans |
|  | Shares Available for Grant |  |  | Number of Shares Outstanding |  |  | Weighted-Average Exercise Price |
Balance as of December 31, 2017 |  |  | 196 |  |  |  | 2,189 |  |  | $ | 2.70 |
Authorized |  |  | 655 |  |  |  | - |  |  |  | - |
Granted |  |  | (1,148 | ) |  |  | 1,148 |  |  |  | 1.07 |
Exercised |  |  | - |  |  |  | (2 | ) |  |  | 0.67 |
Forfeited/expired |  |  | 446 |  |  |  | (446 | ) |  |  | 4.35 |
Balance as of December 31, 2018 |  |  | 149 |  |  |  | 2,889 |  |  | $ | 1.80 |
Authorized |  |  | 855 |  |  |  | - |  |  |  | - |
Granted |  |  | (1,116 | ) |  |  | 1,116 |  |  |  | 0.78 |
Forfeited/expired |  |  | 259 |  |  |  | (259 | ) |  |  | 3.53 |
Balance as of December 31, 2019 |  |  | 147 |  |  |  | 3,746 |  |  | $ | 1.38 |
Vested and unvested awards outstanding |
|  | Number of Shares |  |  | Weighted Average Exercise Price |  |  | Remaining Contractual Term (In Years) |  |  | Average Intrinsic Value1 |
2019 |  |  |  |  |  |  |  |  |  |  |  |
Vested and Exercisable |  |  | 2,659 |  |  | $ | 1.56 |  |  |  | 7.45 |  |  | $ | 145 |
Unvested |  |  | 1,087 |  |  |  | 0.93 |  |  |  | 8.78 |  |  |  | 77 |
Total |  |  | 3,746 |  |  | $ | 1.38 |  |  |  | 7.84 |  |  | $ | 222 |
2018 |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Vested and Exercisable |  |  | 1,923 |  |  | $ | 2.01 |  |  |  | 7.34 |  |  | $ | - |
Unvested |  |  | 966 |  |  |  | 1.38 |  |  |  | 8.81 |  |  |  | - |
Total |  |  | 2,889 |  |  | $ | 1.80 |  |  |  | 7.80 |  |  | $ | - |
Schedule of weighted average fair value calculations for options |
Description |  | For the years ended December 31, |
|  | 2019 |  |  | 2018 |
Dividend-yield |  |  | 0 | % |  |  | 0 | %
Risk-free interest rate |  |  | 2.38 | % |  |  | 2.71 | %
Expected volatility |  |  | 88.54 | % |  |  | 82.99 | %
Expected life (years) |  |  | 6.55 |  |  |  | 6.48 |
Market value per share on grant date |  | $ | 0.78 |  |  | $ | 1.07 |
Fair value per share on grant date |  | $ | 0.59 |  |  | $ | 0.79 |

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