Number of shares issued pursuant to the terms of a deferred compensation arrangement.

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Stock-Based Compensation - Additional Information (Detail) - USD ($)				3 Months Ended		6 Months Ended
	Jun. 30, 2020	May 26, 2020	Jan. 06, 2019	Jun. 30, 2020	Jun. 30, 2019	Jun. 30, 2020	Jun. 30, 2019	Jun. 29, 2020	Dec. 31, 2019
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Outstanding options issued	6,561,513			6,561,513		6,561,513			5,842,879
Stock options, granted				153,000	199,422	1,049,000	1,695,755
Options available for future grant	6,032,404			6,032,404		6,032,404
Weighted-average grant date fair value				$ 1.99	$ 3.13	$ 2.55	$ 1.80
Number of shares issued for accrued annual performance bonus			446,428
Number of options vested	31,220	448,130
Adiitional stock compensation expenses				$ 154,000		$ 154,000
Restricted Stock
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Number of shares vested		45,277
Unvested Stock
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Unrecognized compensation costs related to unvested restricted stock outstanding	$ 7,700,000			7,700,000		$ 7,700,000
Expected recognition period						1 year 9 months 21 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	$ 3,100,000			$ 3,100,000		$ 3,100,000
Expected recognition period						1 year 6 months 21 days
Number of shares vested						0
Outside 2012 Plan
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Outstanding options issued	863,333			863,333		863,333
2020 Equity Incentive Plan [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
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