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The number of shares under options that were cancelled during the reporting period as a result of occurrence of a terminating event specified in contractual agreements pertaining to the stock option plan.

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Gross number of share options (or share units) granted during the period.

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Amount by which the current fair value of the underlying stock exceeds the exercise price of options outstanding.

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Number of options outstanding, including both vested and non-vested options.

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Maximum number of shares that may be issued in accordance with the plan as a proportion of outstanding capital stock.

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Weighted average per share amount at which grantees can acquire shares of common stock by exercise of options.

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Share Based Compensation - Additional Information (Details) $ / shares in Units, $ in Thousands		12 Months Ended
	Jan. 01, 2019 $ / shares shares	Dec. 31, 2020 USD ($) Installment $ / shares shares	Dec. 31, 2019 USD ($) shares	Oct. 31, 2020 shares	Feb. 29, 2016 shares
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Number of performance-condition options granted		828,000
Exercise price \| $ / shares		$ 2.81
Number of outstanding stock options granted		2,321,000	1,916,000
Remaining life of outstanding performance condition options		7 years 4 months 24 days	7 years 7 months 6 days
Intrinsic value \| $		$ 42,580
Stock compensation expense \| $		$ 3,709	$ 170
Restricted Stock Units (RSUs)
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
RSUs outstanding		79,104
Weighted average grant date fair value \| $ / shares		$ 6.83
Bonus-To-Options Program
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Intrinsic value \| $		$ 1,600
Stock compensation expense \| $		3,400
Options and Restricted Stock Units
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Unrecognized remaining stock based compensation balance \| $		$ 600
Amortization period		3 years 8 months 12 days
Service Condition R S Us
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Vesting term		vest over three years, 40% over the first two years and the remaining 60% over the third year from the grant date.
Number of RSUs granted		52,736
Service Condition R S Us \| Share-based Payment Arrangement, Tranche One
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Vesting percentage		40.00%
Service Condition R S Us \| Share-based Payment Arrangement, Tranche Two
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Vesting percentage		60.00%
Maximum \| Bonus-To-Options Program
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Option expiration period		10 years
Number of outstanding stock options granted		173,229
Percentage of fully diluted equity for bonus awarded		1.00%
Weighted average exercise price,vested \| $ / shares		$ 11.11
Minimum \| Service Condition R S Us
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Vesting period		3 years
2020 Equity Incentive Plan
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Number of shares reserved for issuance		1,893,395
2020 Equity Incentive Plan \| Performance Condition Options
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Option expiration period	10 years
Vesting term		Performance-based options vest in three equal annual installments beginning one year after the grant date
Number of equal annual installments for award vesting \| Installment		3
Number of performance-condition options granted	168,466
Exercise price \| $ / shares	$ 0.77
Options vested		56,155
Options forfeited			56,155
Number of outstanding stock options granted		56,156
Remaining life of outstanding performance condition options		8 years
2020 Equity Incentive Plan \| Maximum
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Option expiration period		10 years
2020 Equity Incentive Plan \| Minimum \| Restricted Stock Units (RSUs)
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Vesting period		3 years
2020 Equity Incentive Plan \| Common Stock
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Percentage of number of shares of common stock issued and outstanding		4.00%
2020 Equity Incentive Plan \| Common Stock \| Maximum
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Number of common stock may be issued under incentive plan		1,893,395
2006 Plan \| Maximum
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Number of shares authorized		831,389
2016 Plan
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Additional stock awards granted					0
2016 Plan \| Maximum
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Number of shares authorized					1,431,964
2006 Plan, 2016 Plan and 2020 Equity Incentive Plan
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Additional stock awards granted		4,647,380
Employee Stock Purchase Plan
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Number of shares reserved for issuance				338,106
Percentage of number of shares of common stock issued and outstanding		1.00%
Percentage of earnings used for purchase of common stock		15.00%
Percentage of fair market value of common stock for purchase under plan		85.00%
Description of voting power or value of stock for employee participation in offering period		No employee may participate in an offering period if the employee owns 5% or more of the total combined voting power or value of the Company’s stock.
Description of offering period under plan		The initial offering period will commence from January 1, 2021 through August 31, 2021. On a going forward basis, the ESPP provides for successive six-month offering periods beginning on September 1st and March 1st of each year.