Income Taxes - Schedule of Expected Income Tax (Benefit) Computed Using Federal Statutory Income Tax Rate to Company's Effective Income Tax Rate (Detail)	12 Months Ended
Dec. 31, 2021	Dec. 31, 2020
Effective Income Tax Rate Reconciliation, Percent [Abstract]
Income tax computed at federal statutory rate	21.00%	21.00%
State taxes, net of federal benefit	6.91%	6.90%
R&D credit carryovers	0.90%	1.40%
Change in valuation allowance	(27.42%)	(27.24%)
Stock based compensation	(1.19%)	(0.24%)
Permanent differences	(0.31%)	0.27%
Change in fair value of derivatives	0.00%	(2.25%)
Effective income tax rate	(0.11%)	(0.15%)

Effective income tax rate reconciliation change in fair value of derivatives.

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

+ References

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-Publisher FASB
-Name Accounting Standards Codification
-Topic 740
-SubTopic 10
-Section 50
-Paragraph 12
-URI http://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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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
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-SubTopic 10
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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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