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Stock-Based Compensation - Additional Information (Details) - USD ($)	12 Months Ended
	Dec. 31, 2021	Dec. 31, 2020	Dec. 31, 2019
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Common stock, initially reserved for issuance	5,146,427	3,924,191
Stock-based compensation expense	$ 8,237,000	$ 3,609,000	$ 2,168,000
Weighted-average grant-date fair value of options granted	$ 16.09	$ 6.16
Aggregate intrinsic value of options exercised	$ 3,500,000	$ 1,700,000
Total unrecognized stock-based compensation expense for stock options	$ 22,200,000
Total unrecognized stock-based compensation expense, weighted-average period of recognition	2 years 7 months 9 days
Common stock repurchased	0	10,518
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	0	14,460
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	$ 0
Maximum \| 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
Restricted Stock
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Stock-based compensation expense	0
Total fair value of stock vested	$ 100,000	$ 0
Shares of restricted stock	0	14,625
Aggregate purchase price of unvested restricted stock subject to repurchase	$ 0
Restricted Stock \| Maximum
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Aggregate purchase price of unvested restricted stock subject to repurchase		$ 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	$ 300,000	$ 200,000
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