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.

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+ Details

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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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+ Details

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

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+ 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.

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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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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
-Topic 718
-SubTopic 10
-Section S99
-Paragraph 1
-Subparagraph (SAB Topic 14.D.2)
-URI http://asc.fasb.org/extlink&oid=115993241&loc=d3e301413-122809

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Stock Plans and Stock-Based Compensation - Schedule of Assumptions Used in Determining Fair Value of Stock Option Grants (Details) - $ / shares	3 Months Ended		9 Months Ended
	Sep. 30, 2019	Sep. 30, 2018	Sep. 30, 2019	Sep. 30, 2018
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	6 months
Expected volatility	45.00%		45.00%
Expected volatility, maximum		50.00%		60.00%
Expected volatility, minimum		45.00%		45.00%
Risk-free interest rate, maximum	2.52%	2.33%	2.52%	2.33%
Risk-free interest rate, minimum	1.93%	1.89%	1.93%	1.18%
Dividend rate	0.00%	0.00%	0.00%	0.00%
Employee Stock Options
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Fair value per share on grant date		$ 58.75
Expected term (in years)		6 years		6 years
Expected volatility		45.00%
Expected volatility, maximum				50.00%
Expected volatility, minimum				45.00%
Risk-free interest rate		2.72%
Risk-free interest rate, maximum				2.98%
Risk-free interest rate, minimum				2.72%
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
Employee Stock Options \| Maximum
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Fair value per share on grant date				$ 58.75