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The discounted percentage of the fair market value of the Company's common stock for stock purchase in employee stock purchase plan.

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Percentage of voting power of all classes of stock.

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The maximum offering period that could be set for the Employee Stock Purchase Plan.

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Number of shares of common stock subject to repurchase at a period end.

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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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Amount of cost to be recognized for option under share-based payment arrangement.

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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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Fair value of share-based awards for which the grantee gained the right by satisfying service and performance requirements, to receive or retain shares or units, other instruments, or cash.

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

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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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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 that have been repurchased during the period and have not been retired and are not held in treasury. Some state laws may govern the circumstances under which an entity may acquire its own stock and prescribe the accounting treatment therefore. This element is used when state law does not recognize treasury stock.

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Stock-Based Compensation - Additional Information (Details) - USD ($)	12 Months Ended
	Dec. 31, 2020	Dec. 31, 2019	Dec. 31, 2018
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Common stock, initially reserved for issuance	3,924,191	3,194,078
Stock-based compensation expense	$ 3,609,000	$ 2,168,000	$ 950,000
Weighted-average grant-date fair value of options granted	$ 6.16	$ 6.73
Aggregate intrinsic value of options exercised	$ 1,700,000	$ 800,000
Total unrecognized stock-based compensation expense for stock options	$ 8,500,000
Total unrecognized stock-based compensation expense, weighted-average period of recognition	2 years 6 months 3 days
Common stock repurchased	10,518	23,698
Estimated dividend yield	0.00%	0.00%	0.00%
Issuance of Common Stock Options
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Shares subject to repurchase	14,460	84,964
Other Current Liabilities and Other Non-Current Liabilities
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Aggregate exercise prices of early exercised shares	$ 100,000	$ 100,000
Restricted Stock
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Stock-based compensation expense	0
Total fair value of stock vested	$ 0	$ 100,000
Shares of restricted stock	14,625	14,625
Aggregate purchase price of unvested restricted stock subject to repurchase	$ 100,000	$ 100,000
2019 Equity Incentive Plan
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Term of options	10 years
Vesting period of options	4 years
2019 Equity Incentive Plan \| Cliff Vesting
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Vesting period of options	1 year
2019 Equity Incentive Plan \| 10% Stockholder
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Term of options	5 years
2019 Equity Incentive Plan \| Incentive Stock Options and Nonqualified Stock Options \| Minimum [Member]
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Percentage of fair value of the shares on the grant date	100.00%
2019 Equity Incentive Plan \| Incentive Stock Options
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Percentage of voting power of all classes of stock	10.00%
2019 Equity Incentive Plan \| Incentive Stock Options \| Minimum [Member]
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Percentage of fair value of the shares on the grant date	110.00%
2019 Employee Stock Purchase Plan
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Common stock, initially reserved for issuance	195,000
Stock-based compensation expense	$ 200,000	$ 100,000
Maximum offering period under ESPP	27 months
Maximum eligible rate of compensation	15.00%
2019 Employee Stock Purchase Plan \| Maximum
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Percentage of the fair value of common stock	85.00%
Maximum number of shares purchasable	4,000