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

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Amount of cost to be recognized for nonvested award under share-based payment arrangement. Excludes share and unit options.

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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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The number of grants made during the period on other than stock (or unit) option plans (for example, phantom stock or unit plan, stock or unit appreciation rights plan, performance target plan).

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The weighted average fair value at grant date for nonvested equity-based awards issued during the period on other than stock (or unit) option plans (for example, phantom stock or unit plan, stock or unit appreciation rights plan, performance target plan).

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

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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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Stock-based Compensation - Additional Information (Details) - USD ($)	1 Months Ended		5 Months Ended	12 Months Ended
	Jul. 31, 2021	Jan. 31, 2021	Dec. 31, 2021	Dec. 31, 2021	Dec. 31, 2020	Dec. 31, 2018
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Common stock reserved for future issuance			29,685,655	29,685,655	77,822,703
Share-based compensation, shares subject to repurchase			1,854,427	1,854,427	2,131,510
Stock-based compensation				$ 8,331,000	$ 797,000
Share-based compensation, vesting rights description				The restricted stock vests 25% one year from the vesting commencement date and monthly thereafter over a three-year period and is subject to repurchase by the Company in the event of any voluntary or involuntary termination of services to the Company prior to vesting.
Accrued Expenses and Other Current Liabilities
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Share-based compensation, liabilities associated with shares issued with repurchase rights			$ 2,900,000	$ 2,900,000	$ 2,500,000
Minimum
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Share-based compensation, common stock grant in period, term				5 years
Stock Options
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Common stock reserved for future issuance			13,818,212	13,818,212	6,541,422
Stock vesting period				4 years
Weighted-average grant date fair value of options granted				$ 4.16	$ 0.82
Unrecognized compensation cost related to unvested stock option grants			$ 32,100,000	$ 32,100,000
Unrecognized compensation cost expected to be recognized as expense, period				2 years 10 months 28 days
Intrinsic value of options exercised				$ 3,100,000	$ 141,000
Share-based compensation, options granted that vest based on performance milestone		250,000		8,320,187
Stock Options \| Minimum \| At the Time Option is Granted
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Percentage of fair market value of common stock				100.00%
Stock Options \| Minimum \| For Holders of More Than 10% of Company's Total Combined Voting Power of All Classes of Stock
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Percentage of fair market value of common stock				110.00%
Stock Options \| Maximum
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Share-based compensation, plan expiration period				10 years
Performance-based Options
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Stock-based compensation				$ 115,000	$ 0
Restricted Stock
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Stock vesting period						3 years
Restricted stock granted				0	0	1,795,827
Weighted-average grant date fair value of restricted stock granted						$ 0
Share-based Compensation, common stock shares subject to forfeiture			212,941	212,941	557,731
Total unrecognized compensation related to unvested restricted stock awards granted			$ 0	$ 0
Restricted Stock \| One Year from the Vesting Commencement Date and Monthly Thereafter Over Three-year Vesting Period
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Stock vesting percentage						25.00%
Share-based compensation, vesting rights description				The Company granted 1,795,827 shares of its restricted stock in 2018, which vest 25% one year from the vesting commencement date and monthly thereafter over a three-year period.
Restricted Stock \| 25% One Year from Vesting Commencement Date
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Stock vesting period						1 year
Restricted Stock \| Monthly Thereafter Over Three-year Vesting Period
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Stock vesting period						3 years
2018 Equity Incentive Plan
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Share-based compensation, options granted that vest based on performance milestone			0
2021 Incentive Award Plan
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Common stock reserved for future issuance			14,699,430	14,699,430
Shares of common stock, authorized for issuance	15,150,000
Percentage of outstanding common stock maximum	5.00%
ESPP
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Common stock reserved for future issuance	1,260,000
Unrecognized compensation cost related to unvested stock option grants			$ 3,700,000	$ 3,700,000
Unrecognized compensation cost expected to be recognized as expense, period				1 year 3 months 10 days
Stock-based compensation				$ 688,000
Share-based payment arrangement, withheld on behalf of employees for future purchase			$ 102,000	$ 102,000
Offering period	24 months
Purchase period	6 months
Shares issued under ESPP				91,987
ESPP \| Minimum
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Percentage of fair market value of common stock	85.00%