Income Taxes - Additional Information (Detail) - USD ($)	12 Months Ended
	Dec. 31, 2021	Dec. 31, 2020	Dec. 31, 2019	Dec. 31, 2017	Dec. 31, 2018
Income Tax Disclosure [Line Items]
Valuation allowance, deferred tax assets	$ 43,329,000	$ 37,856,000
Research and development tax credit carryforwards	36,041,000	29,046,000
Accrued interest	3,246,000	2,297,000	$ 2,070,000		$ 1,462,000
Net interest expense	19,000	17,000	$ 7,000
Potential payment of interest	52,000	58,000
Stock-based compensation	2,341,000	1,796,000
Maximum [Member]
Income Tax Disclosure [Line Items]
Stock-based compensation	55,300,000	$ 49,500,000
Domestic Tax Authority [Member]
Income Tax Disclosure [Line Items]
Federal net operating loss carryforwards expiry, beginning year				2025
Research and development tax credit carryforwards				$ 13,970,000
Domestic Tax Authority [Member] | Tax Year 2017 [Member]
Income Tax Disclosure [Line Items]
Net operating loss carryforwards	$ 25,963,000
Certain States [Member]
Income Tax Disclosure [Line Items]
Federal net operating loss carryforwards expiry, beginning year				2021
Research and development tax credit carryforwards				$ 24,807,000
VICR Certain States Member [Member] | Tax Year 2017 [Member]
Income Tax Disclosure [Line Items]
Federal net operating loss carryforwards expiry, beginning year	2025
Net operating loss carryforwards	$ 24,804,000