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

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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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Rate of weighted-average expected volatility for award under share-based payment arrangement.

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

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Stock-Based Compensation and Other Incentive Plans (Narrative) (Details) - USD ($) shares in Millions, $ in Millions	12 Months Ended
	Dec. 31, 2020	Dec. 31, 2019	Dec. 31, 2018
Restricted Stock Units
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Share-based compensation expense	$ 17.4	$ 22.0	$ 17.5
Unrecognized share-based compensation expense	$ 15.7
Weighted-average period for recognition of unrecognized share-based compensation expense	2 years
Time Based Awards \| Maximum
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Vesting period	3 years
Performance Based Awards
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Vesting period	3 years
Volatility rate	36.00%
2016 Omnibus Incentive Plan
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Shares authorized for incentive plan (in shares)	3.0
Number of shares available for grant (in shares)	2.1