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Stock-Based Compensation - Additional Information (Detail) - USD ($) $ / shares in Units, $ in Millions				3 Months Ended		6 Months Ended
	Apr. 29, 2021	Apr. 05, 2021	Mar. 04, 2021	Jun. 30, 2021	Jun. 30, 2020	Jun. 30, 2021	Jun. 30, 2020	May 17, 2021	Dec. 31, 2020	Jun. 29, 2020
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Outstanding options issued		751,371		10,186,829		10,186,829		347,267	6,840,719
Stock options, granted				41,500	153,000	4,395,438	1,049,000
Options available for future grant				1,427,152		1,427,152
Weighted-average grant date fair value				$ 2.27	$ 1.99	$ 2.44	$ 2.55
Number of options vested	10,417		216,700
Adiitional stock compensation expenses				$ 1.9		$ 2.0
Unvested Stock
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Unrecognized compensation costs related to unvested restricted stock outstanding				11.3		$ 11.3
Expected recognition period						1 year 9 months 25 days
Number of Unvested Stock options	167,023
Unvested Restricted Common Stock
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Unrecognized compensation costs related to unvested restricted stock outstanding				$ 2.2		$ 2.2
Expected recognition period						1 year 8 months 4 days
Restricted Stock
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Number of Accelerated Vesting Share	4,137	226,889
Outside 2012 Plan
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Outstanding options issued				463,333		463,333
2020 Equity Incentive Plan [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Options available for future grant				1,427,152		1,427,152
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		0
2003 Equity Incentive Plan [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Options available for future grant				0		0