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Stock-Based Compensation - Additional Information (Detail) - USD ($)		3 Months Ended
	Mar. 04, 2021	Mar. 31, 2021	Mar. 31, 2020	Dec. 31, 2020	Jun. 29, 2020
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Outstanding options issued		10,718,378		6,840,719
Stock options, granted		4,314,438	896,000
Options available for future grant		1,267,888
Weighted-average grant date fair value		$ 2.43	$ 2.64
Number of options vested	216,700
Adiitional stock compensation expenses		$ 82,000
Unvested Stock
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Unrecognized compensation costs related to unvested restricted stock outstanding		$ 16,000,000.0
Expected recognition period		1 year 10 months 6 days
Unvested Restricted Common Stock
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Unrecognized compensation costs related to unvested restricted stock outstanding		$ 2,600,000
Expected recognition period		1 year 6 months 25 days
Outside 2012 Plan
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Outstanding options issued		463,333
2020 Equity Incentive Plan [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Options available for future grant		1,287,888
Shares available for new issue					21,000,000
2012 Equity Incentive Plan [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Options available for future grant					0
2003 Equity Incentive Plan [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Options available for future grant					0