Income Taxes - Summary of Provision for Income Taxes Differ from the Amounts Computed by Applying the U.S. Federal Income Tax Rate (Detail)	12 Months Ended
Dec. 31, 2021	Dec. 31, 2020
Effective Income Tax Rate Reconciliation, Percent [Abstract]
Federal tax at statutory rate	21.00%	21.00%
State, net of federal benefit	0.00%	0.00%
Permanent differences	(0.39%)	1.53%
Stock-based compensation	(3.36%)	(1.62%)
Uncertain tax positions	(0.81%)	(1.03%)
General business credits	1.15%	1.44%
Valuation allowance	(10.53%)	(17.97%)
Disqualified interest on debt	(7.10%)	(3.37%)
Effective tax rate	(0.04%)	(0.02%)

Effective income tax rate reconciliation disqualified interest on debt.

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Effective income tax rate reconciliation general business credits.

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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
-URI https://asc.fasb.org/extlink&oid=121826272&loc=d3e32687-109319

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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
-Publisher FASB
-Name Accounting Standards Codification
-Topic 740
-SubTopic 10
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-Paragraph 1
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-Publisher FASB
-Name Accounting Standards Codification
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-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 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)
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-Section 50
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Percentage of difference between reported income tax expense (benefit) and expected income tax expense (benefit) computed by applying domestic federal statutory income tax rate to pretax income (loss) from continuing operation, attributable to nondeductible expense for share-based payment arrangement.

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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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