Income Taxes - Schedule Of Effective Income Tax Rate Reconciliation (Detail) - USD ($) $ in Thousands	12 Months Ended
Dec. 31, 2021	Dec. 31, 2020
Income Tax Disclosure [Abstract]
Tax at the federal statutory rate	$ (18,790)	$ (6,919)
Benefit from R&D tax credits	(1,244)	(586)
Stock-based compensation	1,102	331
Non-deductible executive compensation	817	0
Other temporary and permanent differences	33	21
Change in valuation allowance	18,082	7,153
Total provision for income taxes	$ 0	$ 0

Benefit from R&D tax credits.

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Other temporary and permanent differences.

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

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Amount 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 increase (decrease) in the valuation allowance for deferred tax assets.

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The amount of income tax expense or benefit for the period computed by applying the domestic federal statutory tax rates to pretax income from continuing operations.

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Amount of reported income tax expense (benefit) in excess of (less than) 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 award under share-based payment arrangement. Includes, but is not limited to, expense determined to be nondeductible upon grant or after for award under share-based payment arrangement.

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