Income Taxes - Effective Income Tax Reconciliation (Details)	12 Months Ended
Dec. 31, 2021	Dec. 31, 2020
Income Tax Disclosure [Abstract]
United States federal tax at statutory rate	21.00%	21.00%
Items affecting federal income tax rate:
State tax, net of federal benefit	6.51%	3.44%
Valuation allowance	(37.34%)	(23.07%)
R&D Credit	9.47%	0.00%
NOL Expiration	(1.69%)	(0.41%)
Other adjustments	1.89%	(1.47%)
Effective income tax rate	(0.16%)	(0.51%)

Effective Income Tax Rate Reconciliation, Net Operating Loss Expiration

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Percentage of current income tax expense (benefit) and deferred income tax expense (benefit) pertaining to continuing operations.

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Percentage of domestic federal statutory tax rate applicable to pretax income (loss).

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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.

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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 applicable to state and local income tax expense (benefit), net of federal tax expense (benefit).

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