Income Taxes - Schedule of Reconciliation of the Company's Effective Tax Rate to the Statutory Federal Income Tax Rate (Detail)	12 Months Ended
Dec. 31, 2019	Dec. 31, 2018
Income Tax Disclosure [Abstract]
Federal income tax at statutory federal rate	21.00%	21.00%
State taxes	6.20%	6.20%
Permanent differences	(1.20%)	(0.10%)
Stock-based compensation		(0.40%)
Tax Cuts and Jobs Act impact		0.10%
Tax credits	0.70%	2.50%
Forfeiture of vested stock options	(24.80%)
Other	0.20%
Change in valuation allowance	4.40%	(18.10%)
Total	6.50%	11.20%

Effective income tax rate reconciliation forfeiture of vested stock options 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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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 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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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 tax credits. Including, but not limited to, research credit, foreign tax credit, investment tax credit, and other tax credits.

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