Maximum number of additional common stock capital shares reserved for future issuance.

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Share based compensation arrangement by share based payment award minimum percentage of combined voting rights of common stock holders.

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Share-based compensation arrangement by share-based payment award number of shares subject to repurchase.

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Share based compensation arrangement by share based payment award options not be granted at less than fair market value of common stock at date of grant maximum term.

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Share based compensation arrangement by share based payment award stock options not be granted at less than fair market value of common stock at date of grant percentage.

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Share based compensation arrangement by share based payment award shares issued subject to repurchase liabilities recorded.

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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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Amount of cost not yet recognized for nonvested award under share-based payment arrangement.

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Weighted-average period over which cost not yet recognized is expected to be recognized for award under share-based payment arrangement, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents reported fact of one year, five months, and thirteen days.

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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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The estimated dividend rate (a percentage of the share price) to be paid (expected dividends) to holders of the underlying shares over the option's term.

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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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Number of shares authorized for issuance under share-based payment arrangement.

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

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

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Number of shares issued during the period as a result of an employee stock purchase plan.

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Equity Incentive Plans and Stock-Based Compensation - Additional Information (Details) - USD ($)	1 Months Ended	12 Months Ended
	Apr. 30, 2020	Dec. 31, 2020	Dec. 31, 2019	Dec. 31, 2018
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Intrinsic value of options exercised		$ 2,700,000	$ 100,000	$ 0
Shares subject to repurchase		6,072	29,579	121,794
Expected dividend yield		0.00%	0.00%	0.00%
Weighted-average grant-date fair value of options granted		$ 12.99	$ 5.01	$ 1.41
Stock-based compensation expense		$ 5,278,000	$ 1,094,000	$ 469,000
Total unrecognized compensation expense related to outstanding unvested stock-based awards		$ 20,600,000	$ 6,900,000	$ 2,300,000
Total unrecognized compensation expense related to outstanding unvested stock-based awards expected to be recognized over weighted-average remaining service period		2 years 8 months 12 days	3 years 4 months 24 days	3 years 4 months 24 days
Employee Stock Purchase Plan
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Stock-based compensation expense		$ 0
Maximum
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Liabilities with shares issued with repurchase rights		$ 100,000	$ 100,000
2020 Plan
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Number of common stock initially reserved for issuance	2,656,500
Additional number of shares available for future issuance	2,656,500
Percentage of outstanding shares of common stock	5.00%
Number of shares available for future issuance		1,430,368
2014 Plan
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Number of common stock remained available for issuance	241,653
2020 Plan and 2014 Plan \| Stock Options
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Vesting period		4 years
2020 Plan and 2014 Plan \| Stock Options \| Maximum
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Expiration period		10 years
2020 Plan and 2014 Plan \| Incentive Stock Options
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Exercise price as a percentage of fair market value		100.00%
Minimum percentage required for holders of combined voting power to be eligible for incentive stock options		10.00%
Percentage of options may not be granted at less than fair market value of the common stock at the date of grant		110.00%
Maximum term of options may not be granted at less than fair market value of the common stock at the date of grant		5 years
2020 ESPP
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Additional number of shares available for future issuance	500,000
Percentage of outstanding shares of common stock	1.00%
Number of shares available for future issuance	290,000
Number of shares issued under ESPP		0