Stock Plans and Stock-Based Compensation - Schedule of Assumptions Used in Determining Fair Value of Stock Option Grants and Shares Issuable (Details) - $ / shares	12 Months Ended
Dec. 31, 2019	Dec. 31, 2018	Dec. 31, 2017
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Dividend rate	0.00%
2016 Employee Stock Purchase Plan
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Expected term (in years)	6 months	6 months	6 months
Expected volatility	45.00%		60.00%
Expected volatility, minimum		40.00%
Expected volatility, maximum		60.00%
Risk-free interest rate, minimum	1.93%	1.18%	0.45%
Risk-free interest rate, maximum	2.52%	2.33%	1.18%
Dividend rate	0.00%	0.00%	0.00%
Employee Stock Options
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Expected volatility, minimum		45.00%	50.00%
Expected volatility, maximum		50.00%	60.00%
Risk-free interest rate, minimum		2.72%	1.82%
Risk-free interest rate, maximum		2.98%	2.47%
Dividend rate		0.00%	0.00%
Employee Stock Options \| Minimum
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Fair value per share on grant date		$ 33.06	$ 18.05
Expected term (in years)		6 years	6 years
Employee Stock Options \| Maximum
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Fair value per share on grant date		$ 58.75	$ 26.50
Expected term (in years)			6 years 1 month 9 days

Share based compensation arrangement by share based payment award fair value assumptions fair value of common stock.

No definition available.

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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 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 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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- 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

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.

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No definition available.

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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.

+ 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

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 718
-SubTopic 10
-Section 50
-Paragraph 2
-Subparagraph (f)(2)(i)
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-Publisher FASB
-Name Accounting Standards Codification
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-SubTopic 10
-Section S99
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-Subparagraph (SAB Topic 14.D.2)
-URI http://asc.fasb.org/extlink&oid=115993241&loc=d3e301413-122809

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