Income Taxes - Effective Income Tax Rate Reconciliation (Details)	12 Months Ended
Dec. 31, 2021	Dec. 31, 2020	Dec. 31, 2019
Income Tax Disclosure [Abstract]
Income at US statutory rate	21.00%	21.00%	21.00%
State taxes, net of federal benefit	(8.40%)	12.80%	13.90%
Permanent differences	(1.70%)	(1.20%)	(1.70%)
Return to provision	(0.90%)	0.00%	0.00%
Foreign rate differential	0.60%	0.20%	0.10%
Valuation allowance	(13.70%)	(33.90%)	(33.90%)
Other	(0.20%)	(0.10%)	0.00%
Total income taxes	(3.30%)	(1.20%)	(0.60%)

Effective Income Tax Rate Reconciliation, Return To Provision, Percent

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

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Reference 1: http://www.xbrl.org/2003/role/disclosureRef
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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.

+ References

Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 740
-SubTopic 10
-Section S99
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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 statutory income tax expense (benefit) outside of the country of domicile.

+ References

Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef
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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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