Equity Incentive Plans and Stock-Based Compensation - Summary of Black-Scholes Option Pricing Model to Estimate Stock-based Compensation Expense for Stock Option Awards (Details) - $ / shares	12 Months Ended
Dec. 31, 2020	Dec. 31, 2019
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Expected dividend yield	0.00%	0.00%
Incentive Stock Options and Nonqualified Stock Options
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Expected volatility, minimum	72.10%	74.80%
Expected volatility, maximum	77.50%	82.53%
Risk-free interest rate, minimum	0.27%	1.43%
Risk-free interest rate, maximum	0.82%	2.59%
Incentive Stock Options and Nonqualified Stock Options \| Minimum
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Expected term (in years)	5 years 3 months 3 days	5 years
Underlying common stock fair value	$ 6.22	$ 5.15
Incentive Stock Options and Nonqualified Stock Options \| Maximum
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Expected term (in years)	6 years 9 months	6 years 29 days
Underlying common stock fair value	$ 28.79	$ 7.08

Underlying common stock fair value.

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- Definition

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.

+ References

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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

No definition available.

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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

No definition available.

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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.

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Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
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