Stock-Based Compensation - Schedule of Fair Value of Employee Stock Options (Details)	12 Months Ended
Dec. 31, 2019	Dec. 31, 2018
Employees \| Options to purchase common stock
Share-based Compensation
Expected volatility, Minimum	65.10%	51.90%
Expected volatility, Maximum	74.40%	56.60%
Risk-free interest rate, Minimum	1.46%	2.64%
Risk-free interest rate, Maximum	2.52%	2.94%
Dividend yield	0.00%	0.00%
Employees \| Minimum \| Options to purchase common stock
Share-based Compensation
Expected term (in years)	5 years 3 months 18 days	5 years 8 months 12 days
Employees \| Maximum \| Options to purchase common stock
Share-based Compensation
Expected term (in years)	6 years 1 month 6 days	6 years 1 month 6 days
2016 Employee Stock Purchase Plan
Share-based Compensation
Expected volatility, Minimum	39.60%	59.50%
Expected volatility, Maximum	74.20%	87.80%
Risk-free interest rate, Minimum	1.67%	0.94%
Risk-free interest rate, Maximum	2.66%	2.11%
2016 Employee Stock Purchase Plan \| Minimum
Share-based Compensation
Expected term (in years)	6 months	6 months
2016 Employee Stock Purchase Plan \| Maximum
Share-based Compensation
Expected term (in years)	1 year	1 year

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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- 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.

+ Details

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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.

+ Details

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- Definition

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

+ References

No definition available.

+ Details

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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
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-Publisher FASB
-Name Accounting Standards Codification
-Topic 718
-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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