Summary of Equity B-S-M Assumptiuons (Details) - 2012 Employee Stock Purchase Plan - ESPP	3 Months Ended	6 Months Ended
Jun. 30, 2020	Jun. 30, 2019	Jun. 30, 2020	Jun. 30, 2019
Equity B-S-M Fair Value Assumptions
Expected term (in years)	6 months	6 months	6 months	6 months
Dividend yield	0.00%	0.00%	0.00%	0.00%
Minimum
Equity B-S-M Fair Value Assumptions
Volatility	50.00%	33.00%
Risk-free interest rate	0.15%	2.43%
Maximum
Equity B-S-M Fair Value Assumptions
Volatility	54.10%	45.20%
Risk-free interest rate	1.59%	2.51%

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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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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- Definition

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

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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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