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Stock-Based Compensation - Additional Information (Details) - USD ($)				1 Months Ended	3 Months Ended		9 Months Ended
	Apr. 29, 2021	Apr. 05, 2021	Mar. 04, 2021	Aug. 30, 2021	Sep. 30, 2021	Sep. 30, 2020	Sep. 30, 2021	Sep. 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			11,072,894		11,072,894		347,267	6,840,719
Stock options, granted					2,755,000	203,178	7,150,438	1,252,178
Unrecognized compensation costs related to unvested restricted stock outstanding					$ 2,400		$ 2,400
Expected recognition period							2 years 2 months 8 days
Options available for future grant					2,224,159		2,224,159
Exercise price of stock options							$ 2.86
Weighted-average grant date fair value					$ 1.08	$ 1.96	$ 1.91	$ 2.45
Number of options vested	10,417		216,700
Adiitional stock compensation expenses							$ 2,000.0
Chief Executive Officer
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Stock options, granted				2,625,000
Exercise price of stock options				$ 1.64
Unvested Stock
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Unrecognized compensation costs related to unvested restricted stock outstanding					$ 8,000,000.0		$ 8,000,000.0
Expected recognition period							2 years 10 days
Number of Unvested Stock options	167,023
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					97,500		97,500
2020 Equity Incentive Plan [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Options available for future grant					2,224,159		2,224,159
Shares available for new issue											21,000,000
Number of Unvested Stock options				0
2012 Equity Incentive Plan [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Stock options, granted				0
2003 Equity Incentive Plan [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Stock options, granted				0