Income Taxes - Expense (Details)	12 Months Ended
Dec. 31, 2021	Dec. 31, 2020
Reconciliation of income tax expense
Federal statutory rate	21.00%	21.00%
Stock compensation	(1.48%)	(0.47%)
State taxes	0.00%	0.60%
Research and development credit	2.52%	2.53%
Acquired in-process research and development	0.00%	(8.09%)
NOL carryback due to CARES Act	0.26%	3.26%
Other	(0.15%)	(0.16%)
Valuation allowance	(21.93%)	(14.46%)
Effective income tax rate	0.22%	4.21%

Effective Income Tax Rate Reconciliation, Built In Loss, Percent

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Effective Income Tax Rate Reconciliation, NOL Carryback To CARES Act, Percent

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Effective Income Tax Rate Reconciliation, Net Operating Loss Adjustment Per Section 382, Percent

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Percentage of difference between reported income tax expense (benefit) and expected income tax expense (benefit) owing to permanent differences.

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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 research and development expense.

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