Grant date.

No definition available.

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- Definition

Grant year.

+ References

No definition available.

+ Details

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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.

+ References

+ 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.

+ References

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- Definition

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

+ References

+ 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.

+ Details

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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.

+ References

+ Details

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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)
-URI http://asc.fasb.org/extlink&oid=116856206&loc=d3e5070-113901

Reference 2: http://fasb.org/us-gaap/role/ref/legacyRef
-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-Based Compensation (Stock Option Grants) (Details) - $ / shares	12 Months Ended
	Dec. 31, 2019	Dec. 31, 2018	Dec. 31, 2017
Time-Vested Stock Options [Member] \| 1/12/2018 [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Grant Year		2018
Grant Date		Jan. 12, 2018
Expected Life		6 years
Expected Volatility		44.25%
Expected Dividend Yield		0.00%
Risk Free Interest Rate		2.42%
Weighted-average grant-date fair value		$ 7.57
Time-Vested Stock Options [Member] \| 4/23/2019 [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Grant Year	2019
Grant Date	Apr. 23, 2019
Expected Life	6 years
Expected Volatility	44.87%
Expected Dividend Yield	0.00%
Risk Free Interest Rate	2.40%
Weighted-average grant-date fair value	$ 3.50
Time-Vested Stock Options [Member] \| 1/14/2019 [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Grant Year	2019
Grant Date	Jan. 14, 2019
Expected Life	6 years
Expected Volatility	44.87%
Expected Dividend Yield	0.00%
Risk Free Interest Rate	2.57%
Weighted-average grant-date fair value	$ 3.43
Performance Stock Options [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Expected Life	10 years
Performance Stock Options [Member] \| 1/12/2018 [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Grant Year		2018
Grant Date		Jan. 12, 2018
Expected Volatility		49.33%
Expected Dividend Yield		0.00%
Risk Free Interest Rate		2.55%
Performance Stock Options [Member] \| 7/31/2017 [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Grant Year			2017
Grant Date			Jul. 31, 2017
Expected Volatility			49.22%
Expected Dividend Yield			2.19%
Risk Free Interest Rate			2.30%
Minimum [Member] \| Performance Stock Options [Member] \| 1/12/2018 [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Expected Life		1 year
Weighted-average grant-date fair value		$ 8.51
Minimum [Member] \| Performance Stock Options [Member] \| 7/31/2017 [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Expected Life			11 months 23 days
Weighted-average grant-date fair value			$ 6.88
Maximum [Member] \| Performance Stock Options [Member] \| 1/12/2018 [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Expected Life		2 years 5 months 5 days
Weighted-average grant-date fair value		$ 9.12
Maximum [Member] \| Performance Stock Options [Member] \| 7/31/2017 [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Expected Life			2 years 4 months 21 days
Weighted-average grant-date fair value			$ 7.25