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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

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

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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- Definition

Expected term of share-based compensation awards, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days.

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Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 718
-SubTopic 10
-Section 50
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-Subparagraph (SAB Topic 14.D.2)
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Incentive Plans - Fair Value of Option Award Estimated on Date of Grant using Black-Scholes Pricing Model (Details) - $ / shares	12 Months Ended
	Dec. 31, 2019	Dec. 31, 2018	Dec. 31, 2017
Assumptions
Expected life	3 years
Performance Based Restricted Stock
Assumptions
Expected volatility	46.00%	48.00%	47.00%
Risk-free interest rate	2.50%	2.30%	1.46%
Expected life	3 years	3 years	3 years
Stock Options
Assumptions
Expected life			5 years 3 months 18 days
Minimum \| Stock Options
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Fair value per option grant			$ 7.96
Assumptions
Dividend yield			3.60%
Expected volatility			41.00%
Risk-free interest rate			1.97%