Stockholders' Equity (Tables)
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12 Months Ended |
Dec. 31, 2019 |
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| Share-based Compensation Arrangement by Share-based Payment Award [Line Items] |
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| Schedule of summarizes stock option activities |
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Weighted Average
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Remaining
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Weighted Average
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Contractual Life (in
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Stock Options
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Exercise Price
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years)
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Outstanding at December 31, 2017
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1,241,675
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5.73
|
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9.31
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Options granted
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—
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—
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Outstanding at December 31, 2018
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1,241,675
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$
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5.73
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8.31
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Options granted
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—
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—
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—
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Outstanding at December 31, 2019
|
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1,241,675
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|
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5.73
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7.31
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Options vested and exercisable at December 31, 2019
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388,022
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$
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5.73
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7.31
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| Schedule of stock-based compensation expense |
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For the year ended December 31,
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2019
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2018
|
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General and administrative
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$
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1,790
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$
|
3,664
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Research and development
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|
874
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|
1,296
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Total stock-based compensation expense
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$
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2,664
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$
|
4,960
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| Schedule of warrant activity |
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Weighted Average
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Remaining
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Weighted Average
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Contractual Life (in
|
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Warrants
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Exercise Price
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years)
|
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Outstanding as of December 31, 2017
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5,253,318
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$
|
8.28
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|
3.89
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Granted
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—
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—
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—
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Exercised
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(42,620)
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|
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4.25
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—
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Outstanding as of December 31, 2018
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5,210,698
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$
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8.32
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|
3.10
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Granted
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288,184
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|
3.47
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9.25
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Exercised
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(93,213)
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—
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—
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Outstanding as of December 31, 2019
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5,405,669
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$
|
8.20
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|
2.40
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| Unvested restricted stock awards |
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| Share-based Compensation Arrangement by Share-based Payment Award [Line Items] |
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| Schedules of restricted stock and restricted stock unit activity |
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Weighted Average
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Grant Date Fair
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Number of Shares
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Value
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Nonvested at December 31, 2017
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180,000
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$
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5.73
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Granted
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322,636
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5.78
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Nonvested at December 31, 2018
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502,636
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$
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5.76
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Granted
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119,060
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3.83
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Vested
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—
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—
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Forfeited
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(322,636)
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|
|
5.14
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Nonvested at December 31, 2019
|
|
299,060
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$
|
5.66
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| Unvested restricted stock units |
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| Share-based Compensation Arrangement by Share-based Payment Award [Line Items] |
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| Schedules of restricted stock and restricted stock unit activity |
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Weighted Average
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Grant Date Fair
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Number of Units
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Value
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Nonvested at December 31, 2017
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134,000
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$
|
6.53
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Granted
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1,072,000
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|
8.16
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Vested
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(173,916)
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9.25
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Nonvested at December 31, 2018
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1,032,084
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$
|
7.77
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Granted
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625,000
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|
3.01
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Forfeited
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(344,750)
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7.67
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Vested
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(199,917)
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7.81
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Nonvested at December 31, 2019
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1,112,417
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$
|
5.11
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