Compensation Arrangement with Individual, Recorded Liability, Scenario One

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- Definition

Compensation Arrangement with Individual, Recorded Liability, Scenario Two

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No definition available.

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- Definition

Compensation Expense, Retirement Age

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- Definition

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

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- Definition

Amount of expense for salary, wage, profit sharing; incentive and equity-based compensation; and other employee benefit. Other employee benefit expense includes, but is not limited to, service component of net periodic benefit cost for defined benefit plan. Excludes compensation cost in cost of good and service sold.

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- Definition

Amount of cost capitalized for award under share-based payment arrangement.

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- Definition

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

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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.

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Amount of expenses for special or contractual termination benefits provided to current employees involuntarily terminated under a benefit arrangement associated exit or disposal activities pursuant to an authorized plan. Excludes expenses related to one-time termination benefits, a discontinued operation or an asset retirement obligation.

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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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Share-Based and Other Compensation - Share-Based Compensation Cost Recorded During the Period and Other Compensation (Details) $ in Millions	12 Months Ended
	Dec. 31, 2020 USD ($)	Dec. 31, 2019 USD ($)	Dec. 31, 2018 USD ($)	Dec. 27, 2018 USD ($) age
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Allocated share-based compensation expense	$ 37.6	$ 32.8	$ 35.9
Share-based compensation costs	7.4	5.8	8.0
Unrecognized compensation costs	$ 35.1
Cost not yet recognized, period for recognition	1 year 4 months 24 days
General and Administrative Expense [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Severance costs	$ 14.1
Severance [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Allocated share-based compensation expense	4.5
Chief Executive Officer [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Cash retirement benefit, scenario one				$ 13.2
Cash retirement benefit, scenario two				$ 16.2
Retirement age \| age				73
Compensation expense	$ 1.5	$ 1.5	$ 12.1