Equity Incentive Plans - Schedule of Fair Value Assumptions Stock Options (Details)	12 Months Ended
Dec. 31, 2019	Dec. 31, 2018
Stock Options
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Risk-free interest rate, minimum	1.38%	2.65%
Risk-free interest rate, maximum	2.58%	2.96%
Volatility, minimum	70.25%	69.13%
Volatility, maximum	86.92%	77.62%
Dividend yield	0.00%	0.00%
ESPP
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Risk-free interest rate, minimum	1.46%
Risk-free interest rate, maximum	1.87%
Volatility, minimum	72.08%
Volatility, maximum	78.70%
Dividend yield	0.00%
Minimum [Member] \| Stock Options
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Weighted-average expected life (in years)	4 years 7 months 6 days	5 years 3 months 18 days
Minimum [Member] \| ESPP
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Weighted-average expected life (in years)	5 months 26 days
Maximum \| Stock Options
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Weighted-average expected life (in years)	6 years 1 month 6 days	6 years 1 month 6 days
Maximum \| ESPP
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Weighted-average expected life (in years)	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.

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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.

+ Details

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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

No definition available.

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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.

+ References

No definition available.

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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.

+ References

No definition available.

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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

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