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Stockholders' Equity - Summary of Assumptions (Details) - Employee stock purchase plan - $ / shares	12 Months Ended
	Dec. 31, 2020	Dec. 31, 2019	Dec. 31, 2018
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Expected term	6 months	6 months	6 months
Dividend yield	0.00%	0.00%	0.00%
Weighted-average grant-date fair value per share (in dollars per share)	$ 20.52	$ 9.88	$ 7.14
Minimum
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Expected volatility	52.06%	40.51%	42.07%
Risk-free interest rate	0.12%	1.59%	2.09%
Maximum
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Expected volatility	68.09%	41.81%	44.97%
Risk-free interest rate	0.15%	2.43%	2.50%

X

- 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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-Publisher FASB
-Name Accounting Standards Codification
-Topic 718
-SubTopic 10
-Section 50
-Paragraph 2
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- Definition

The estimated measure of the 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.

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

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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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No definition available.

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- Definition

The weighted average grant-date fair value of options granted during the reporting period as calculated by applying the disclosed option pricing methodology.

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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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