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Income Taxes - Reconciliation of Total Income Tax Provision (Details) | 12 Months Ended
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Dec. 31, 2020 | Dec. 31, 2019
Reconciliation of the total income tax provision tax rate [Abstract] |  |
Income tax expense (benefit) at federal statutory rate | (21.00%) | (21.00%)
Change in valuation allowance | 23.60% | 23.00%
Income tax expense (benefit) at state statutory rate | (8.90%) | (12.20%)
Stock compensation | 6.90% | 13.70%
Mark to market adjustment | (6.10%) | (24.00%)
NOLs expiring and adjustments to NOL | 6.00% | 19.20%
Research credit | (1.10%) | (1.80%)
Return to provision | 1.00% | 3.10%
Change in state rate | (0.50%) | (1.30%)
Permanent interest adjustments |  | 1.10%
Other, net | 0.10% | 0.20%
Total income tax provision | 0.00% | 0.00%

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- Definition Percentage of the difference between reported income tax expense (benefit) and expected income tax expense (benefit) computed by applying the domestic federal statutory income tax rates to pretax income (loss) from continuing operations attributable to net operating loss expiration. + References No definition available. + Details
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- Definition The portion of the difference between the effective income tax rate and domestic federal statutory income tax rate attributable permanent interest adjustments. + References No definition available. + Details
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- Definition Percentage of current income tax expense (benefit) and deferred income tax expense (benefit) pertaining to continuing operations. + References Reference 1: http://www.xbrl.org/2003/role/disclosureRef -Publisher FASB -Name Accounting Standards Codification -Topic 740 -SubTopic 10 -Section 50 -Paragraph 12 -URI http://asc.fasb.org/extlink&oid=84230637&loc=d3e32687-109319 + Details
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- Definition Percentage of the difference between reported income tax expense (benefit) and expected income tax expense (benefit) computed by applying the domestic federal statutory income tax rates to pretax income (loss) from continuing operations attributable to changes in the valuation allowance for deferred tax assets. + References Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef -Publisher FASB -Name Accounting Standards Codification -Topic 740 -SubTopic 10 -Section S99 -Paragraph 1 -Subparagraph (SAB Topic 6.I.Fact.4) -URI http://asc.fasb.org/extlink&oid=116825942&loc=d3e330036-122817 Reference 2: http://www.xbrl.org/2009/role/commonPracticeRef -Publisher FASB -Name Accounting Standards Codification -Topic 740 -SubTopic 10 -Section 50 -Paragraph 12 -URI http://asc.fasb.org/extlink&oid=84230637&loc=d3e32687-109319 + Details
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