Stock-based Compensation - Assumptions used to Determine Fair Value of Stock Option Grants and Stock to be Purchased under ESPP (Details)	3 Months Ended	6 Months Ended
Jun. 30, 2022	Jun. 30, 2021	Jun. 30, 2022	Jun. 30, 2021
Stock Options
Share-Based Compensation Arrangement by Share-Based Payment Award [Line Items]
Risk-free interest rate, minimum	2.53%	1.02%	1.46%	0.59%
Risk-free interest rate, maximum	3.23%	1.09%	3.23%	1.09%
Expected volatility, minimum	85.51%	82.08%	85.51%	82.08%
Expected volatility, maximum	87.11%	82.54%	87.11%	83.88%
Expected term (in years)		6 years 29 days		6 years 29 days
Expected dividend yield	0.00%	0.00%	0.00%	0.00%
ESPP
Share-Based Compensation Arrangement by Share-Based Payment Award [Line Items]
Risk-free interest rate, minimum	2.24%		2.24%
Risk-free interest rate, maximum	3.14%		3.14%
Expected volatility, minimum	84.74%		84.74%
Expected volatility, maximum	87.89%		87.89%
Expected dividend yield	0.00%		0.00%
Minimum \| Stock Options
Share-Based Compensation Arrangement by Share-Based Payment Award [Line Items]
Expected term (in years)	5 years 6 months		5 years 6 months
Minimum \| ESPP
Share-Based Compensation Arrangement by Share-Based Payment Award [Line Items]
Expected term (in years)	6 months		6 months
Maximum \| Stock Options
Share-Based Compensation Arrangement by Share-Based Payment Award [Line Items]
Expected term (in years)	6 years 29 days		6 years 29 days
Maximum \| ESPP
Share-Based Compensation Arrangement by Share-Based Payment Award [Line Items]
Expected term (in years)	1 year 11 months 26 days		1 year 11 months 26 days

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.

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 718
-SubTopic 10
-Section 50
-Paragraph 2
-Subparagraph (f)(2)(iii)
-URI https://asc.fasb.org/extlink&oid=128089324&loc=d3e5070-113901

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- Definition

The estimated measure of the maximum percentage by which a share price is expected to fluctuate during a period. Volatility also may be defined as a probability-weighted measure of the dispersion of returns about the mean. The volatility of a share price is the standard deviation of the continuously compounded rates of return on the share over a specified period. That is the same as the standard deviation of the differences in the natural logarithms of the stock prices plus dividends, if any, over the period.

+ References

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- Definition

The estimated measure of the minimum percentage by which a share price is expected to fluctuate during a period. Volatility also may be defined as a probability-weighted measure of the dispersion of returns about the mean. The volatility of a share price is the standard deviation of the continuously compounded rates of return on the share over a specified period. That is the same as the standard deviation of the differences in the natural logarithms of the stock prices plus dividends, if any, over the period.

+ References

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- Definition

The maximum risk-free interest rate assumption that is used in valuing an option on its own shares.

+ References

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- Definition

The minimum risk-free interest rate assumption that is used in valuing an option on its own shares.

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- Definition

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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- Definition

Expected term of award under share-based payment arrangement, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents reported fact of one year, five months, and thirteen days.

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 718
-SubTopic 10
-Section 50
-Paragraph 2
-Subparagraph (f)(2)(i)
-URI https://asc.fasb.org/extlink&oid=128089324&loc=d3e5070-113901

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