Income Taxes - Effective Income Tax Rate Differs From Statutory Federal Income Tax Rate (Details)	12 Months Ended
Dec. 31, 2021	Dec. 31, 2020	Dec. 31, 2019
Income Tax Disclosure [Abstract]
Federal tax at statutory rate	21.00%	21.00%	21.00%
State and local tax at statutory rate	3.00%	3.00%	5.50%
Research and development tax credits	0.00%	0.10%	2.00%
Change in valuation allowance	(22.70%)	(21.50%)	(22.40%)
Other permanent differences	(1.00%)	(0.40%)	(0.30%)
Reduction in deferred tax assets for change in ownership	0.00%	0.00%	(1.60%)
Effect of rate changes	0.30%	0.80%	(1.40%)
Provision to Return Adjustment	0.30%	(1.50%)	0.00%
Prior Period Adjustment to State NOL DTA	0.00%	(1.50%)	0.00%
Other	(0.90%)	0.00%	(0.50%)
Effective tax rate	0.00%	0.00%	2.30%

Effective income tax rate reconciliation effect of rate changes.

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Effective income tax rate reconciliation, increase (decrease) in deferred tax assets due to change in ownership.

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Effective Income Tax Rate Reconciliation, Prior Year Adjustment, State And Local Jurisdiction, Deferred Tax Assets, Operating Loss Carryforward, Percent

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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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-Publisher FASB
-Name Accounting Standards Codification
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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 the expected income tax expense (benefit) computed by applying the domestic federal statutory income tax rates to pretax income (loss) from continuing operations, that is attributable to tax exempt income, equity in earnings (loss) of an unconsolidated subsidiary, minority interest income (expense), tax holiday, disposition of a business, disposition of an asset, repatriation of foreign earnings, repatriation of foreign earnings jobs creation act of 2004, change in enacted tax rate, prior year income taxes, change in deferred tax asset valuation allowance, and other adjustments.

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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 revisions of previously reported income tax expense.

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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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