Share-based Compensation Arrangement by Share-based, Period in Force

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- Definition

Share-base Payment, Performance Period

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- Definition

Share-based Compensation Arrangement by Share-based Payment Award, Performance Factor, Percentage Of Pre-defined Metric Target

+ References

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- Definition

Amount of expense for award under share-based payment arrangement. Excludes amount capitalized.

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-Name Accounting Standards Codification
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-Section 50
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- Definition

Face amount or stated value per share of common stock.

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- Definition

Amount of cost not yet recognized for nonvested award under share-based payment arrangement.

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- Definition

Weighted-average period over which cost not yet recognized is expected to be recognized for award under share-based payment arrangement, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents reported fact of one year, five months, and thirteen days.

+ References

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- Definition

Amount of cost to be recognized for option under share-based payment arrangement.

+ References

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- Definition

Amount of tax benefit for recognition of expense of award under share-based payment arrangement.

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- Definition

Estimated period over which an employee is required to provide service in exchange for the equity-based payment award, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days.

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- Definition

Period over which grantee's right to exercise award under share-based payment arrangement is no longer contingent on satisfaction of service or performance condition, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents reported fact of one year, five months, and thirteen days. Includes, but is not limited to, combination of market, performance or service condition.

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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

Number of shares authorized for issuance under share-based payment arrangement.

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- Definition

Percentage of vesting of award under share-based payment arrangement.

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Share-Based Payments (General Descriptions) (Details) - USD ($) $ / shares in Units, $ in Millions	3 Months Ended				6 Months Ended
	Jun. 30, 2020	Mar. 31, 2020	Jun. 30, 2019	Mar. 31, 2019	Jun. 30, 2020	Jun. 30, 2019	Dec. 31, 2019	Jun. 20, 2008
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Period in force, from which option holders may elect to sell back acquired shares					90 days
Compensation cost not yet recognized	$ 5.5				$ 5.5		$ 11.2
Pre-tax compensation cost (benefit) recognized	2.4		$ 0.1		(3.8)	$ (1.4)
Compensation cost (benefit), tax expense (benefit)	(0.5)		$ 0.0		0.8	$ 0.3
Compensation cost related to nonvested options not yet recognized	$ 3.7				$ 3.7
Weighted average period over which the compensation is expected to be recognized					1 year 3 months 18 days
Employee SARs granted before 2016 \| Employees
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Requisite service period of awards (in years)					3 years
Employee SARs
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Requisite service period of awards (in years)					1 year
Employee Stock Options and SARs \| Director
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Requisite service period of awards (in years)					1 year
RSU
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Vesting percentage (in percentage)					100.00%
Requisite service period of awards (in years)					3 years
Vesting period (in years)					3 years
RSU \| Director
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Requisite service period of awards (in years)					1 year
PSU
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Vesting period (in years)					3 years
Performance period (in years)					3 years
Performance factor used to determine compensation payout		101.19%		93.86%
Vesting After Service Period, Year One \| Employee SARs granted before 2016 \| Employees
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Vesting percentage (in percentage)					20.00%
Vesting After Service Period, Year One \| Employee SARs
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Vesting percentage (in percentage)					33.30%
Vesting After Service Period, Year One \| Employee Stock Options and SARs \| Director
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Vesting percentage (in percentage)					20.00%
Vesting After Service Period, Year Two \| Employee SARs granted before 2016 \| Employees
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Vesting percentage (in percentage)					20.00%
Vesting After Service Period, Year Two \| Employee SARs
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Vesting percentage (in percentage)					33.30%
Vesting After Service Period, Year Two \| Employee Stock Options and SARs \| Director
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Vesting percentage (in percentage)					20.00%
Vesting After Service Period, Year Three \| Employee SARs granted before 2016 \| Employees
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Vesting percentage (in percentage)					20.00%
Vesting After Service Period, Year Three \| Employee SARs
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Vesting percentage (in percentage)					33.30%
Vesting After Service Period, Year Three \| Employee Stock Options and SARs \| Director
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Vesting percentage (in percentage)					20.00%
Vesting After Service Period, Year Four \| Employee SARs granted before 2016 \| Employees
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Vesting percentage (in percentage)					20.00%
Vesting After Service Period, Year Four \| Employee Stock Options and SARs \| Director
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Vesting percentage (in percentage)					20.00%
Vesting After Service Period, Year Five \| Employee SARs granted before 2016 \| Employees
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Vesting percentage (in percentage)					20.00%
Vesting After Service Period, Year Five \| Employee Stock Options and SARs \| Director
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Vesting percentage (in percentage)					20.00%
Class A
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Common stock, par value (in dollars per share)	$ 0.01				$ 0.01		$ 0.01
Class A \| 2008 Plan
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Common stock, par value (in dollars per share)								$ 1.00
Share-based payments, number of shares authorized under plans (in shares)								300,000