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Income Taxes - Reconciliation of Total Income Tax Provision (Details) | 12 Months Ended
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Dec. 31, 2021 | Dec. 31, 2020
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 | 0.90% | 23.60%
Income tax expense (benefit) at state statutory rate | (0.60%) | (8.90%)
Stock compensation | 0.70% | 6.90%
NOLs expiring and adjustments to NOL | 20.30% | 6.00%
Research credit | (0.80%) | (1.10%)
Return to provision | 0.50% | 1.00%
Change in state rate |  | (0.50%)
Mark to market adjustment |  | (6.10%)
Other, net |  | 0.10%
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 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=121826272&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=122134291&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=121826272&loc=d3e32687-109319 + Details
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