Stock Incentive Plans (Details 4)	12 Months Ended
Dec. 31, 2019 $ / shares
Stock Incentive Plans Details 4
Weighted average fair value per option	$ 6.09
Expected term	5 years 1 month 6 days
Risk-free interest rate	2.95%
Volatility	47.00%
Dividend yield
Forfeiture rate	24.43%

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- Definition

Share-based compensation arrangement by share-based payment award fair value assumptions expected forfeiture rate.

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

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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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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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