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8. Stock-Based Compensation (Tables) | 6 Months Ended
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Jun. 30, 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, 2018 |  |  | 149 |  |  |  | 2,889 |  |  | $ | 1.80 |
Authorized |  |  | 855 |  |  |  | - |  |  |  | - |
Granted |  |  | (1,116 | ) |  |  | 1,116 |  |  |  | 0.78 |
Forfeited/expired |  |  | 190 |  |  |  | (190 | ) |  |  | 3.11 |
Balance as of June 30, 2019 |  |  | 78 |  |  |  | 3,815 |  |  | $ | 1.50 |
Schedule of weighted average fair value calculations for options |
|  | For the three months ended June 30, |
Description |  | 2019 |  |  | 2018 |
Dividend-yield |  |  | 0 | % |  |  | 0 | %
Risk-free interest rate |  |  | 2.00 | % |  |  | 3.04 | %
Expected volatility |  |  | 88.58 | % |  |  | 85.6 | %
Expected life (years) |  |  | 6.81 |  |  |  | 6.48 |
Market value per share on grant date |  | $ | 0.92 |  |  | $ | 1.71 |
Fair value per share on grant date |  | $ | 0.71 |  |  | $ | 1.28 |
Schedule of weighted average fair value calculations for SARs |
Description |  | June 30, 2019 |  |  | December 31, 2018 |
Risk-free interest rate |  |  | 2.20 | % |  |  | 2.60 | %
Expected volatility |  |  | 101 | % |  |  | 125 | %
Market value per share |  | $ | 0.85 |  |  | $ | 0.61 |
Fair value per share on grant date |  | $ | 1.14 |  |  | $ | 1.08 |
Activity of level 3 liabilities |
| SARs Liability Balance
Balance as of December 31, 2018 |  | $ | 1,132 |
Related change in fair value |  |  | 35 |
Balance as of March 31, 2019 |  | $ | 1,167 |
Related change in fair value |  |  | 25 |
Balance as of June 30, 2019 |  | $ | 1,192 |

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- Definition Tabular disclosure of the effect of fair value measurements using significant unobservable inputs (Level 3) on changes in plan assets of pension plans and/or other employee benefit plans for the period. + References Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef -Publisher FASB -Name Accounting Standards Codification -Topic 715 -SubTopic 20 -Section 50 -Paragraph 1 -Subparagraph (d)(iv)(02) -URI http://asc.fasb.org/extlink&oid=118255775&loc=d3e1928-114920 + Details
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- Definition Tabular disclosure of the significant assumptions used during the year to estimate the fair value of stock options, including, but not limited to: (a) expected term of share options and similar instruments, (b) expected volatility of the entity's shares, (c) expected dividends, (d) risk-free rate(s), and (e) discount for post-vesting restrictions. + References Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 718 -SubTopic 10 -Section 50 -Paragraph 2 -Subparagraph (f)(2) -URI http://asc.fasb.org/extlink&oid=116856206&loc=d3e5070-113901 + Details
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