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Incentive stock option granted to Employees Owning percentage of shares of common stock.

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Number of options exercised, excludes options exercised from NPLN.

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Offering period.

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Percentage of fair value per share on the grant date.

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Percentage of provisions subject to stockholders.

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Purchase period.

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Remaining liabilities related to early exercised shares.

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Share based compensation arrangement by share based payment award number of shares increase in available for grant.

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Stock options granted term.

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Amount of expense for award under share-based payment arrangement. Excludes amount capitalized.

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Aggregate number of common shares reserved for future issuance.

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Period over which grantee's right to exercise award under share-based payment arrangement is no longer contingent on satisfaction of service or performance condition, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents reported fact of one year, five months, and thirteen days. Includes, but is not limited to, combination of market, performance or service condition.

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Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table.

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The highest percentage of annual salary that an employee is permitted to utilize with respect to the plan.

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The difference between the maximum number of shares (or other type of equity) authorized for issuance under the plan (including the effects of amendments and adjustments), and the sum of: 1) the number of shares (or other type of equity) already issued upon exercise of options or other equity-based awards under the plan; and 2) shares (or other type of equity) reserved for issuance on granting of outstanding awards, net of cancellations and forfeitures, if applicable.

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Amount of accumulated difference between fair value of underlying shares on dates of exercise and exercise price on options exercised (or share units converted) into shares.

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

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The weighted average grant-date fair value of options granted during the reporting period as calculated by applying the disclosed option pricing methodology.

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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 price at which option holders acquired shares when converting their stock options into shares.

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Percentage of vesting of award under share-based payment arrangement.

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Period from grant date that an equity-based award expires, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days.

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Number of options vested.

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Purchase price of common stock expressed as a percentage of its fair value.

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Equity Incentive Plans - Additional Information (Details) - USD ($) $ / shares in Units, $ in Millions			3 Months Ended			9 Months Ended
	Jan. 01, 2021	Jun. 11, 2020	Sep. 30, 2021	Sep. 30, 2020	Jun. 30, 2020	Sep. 30, 2021	Sep. 30, 2020	Dec. 31, 2020
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Vesting percentage for stock options granted		25.00%
Vesting period for stock options granted		4 years
Early exercised stock options			8,337			8,337		15,056
Options granted						62,382
Exercise of stock options (in shares)			125,583	67,792		578,194	263,626
Weighted-average price per share			$ 3.91	$ 1.60		$ 2.50	$ 1.86
Weighted-average grant date fair value of options granted			$ 17.00	$ 29.83		$ 14.37	$ 8.17
Intrinsic value of the stock options exercised			$ 2.5	$ 2.5		$ 12.4	$ 5.1
Performance-based Awards
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Stock-based compensation expense					$ 0.3		$ 0.3
Performance-based Awards \| IPO
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Number of shares vested					362,935		362,935
2020 Equity Incentive Plan
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Exercise price expire in years form the date of grant		5 years
Stock options granted term		10 years
Percentage of provisions subject to stockholders		10.00%
Shares reserved for issuance		10,150,000
Term of plan		10 years
Percentage of outstanding number of shares		5.00%
Available for issuance of shares increased	2,553,579
Aggregate number of shares available for issuance			6,321,076			6,321,076
Number of shares outstanding			1,465,620			1,465,620
2014 Equity Incentive Plan
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Number of shares outstanding			3,961,387			3,961,387
2020 Employee Stock Purchase Plan
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Shares reserved for issuance		650,000
Term of plan		10 years
Percentage of outstanding number of shares		1.00%
Available for issuance of shares increased	510,715
Aggregate number of shares available for issuance			1,097,964			1,097,964
Percentage of payroll deductions of eligible compensation		15.00%
Employees purchase shares of common stock of lower of fair market value		85.00%
Offering period		2 years
Purchase period		6 months
Maximum \| Other Liabilities
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Remaining liabilities related to early exercised shares			$ 0.1			$ 0.1		$ 0.1
Maximum \| 2020 Equity Incentive Plan
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Percentage of fair value per share on the grant date		110.00%
Minimum \| 2020 Equity Incentive Plan
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Incentive stock option granted to employees owning percentage of shares of common stock		10.00%