Employee Costs (Schedule Of Employee Compensation) (Details) - USD ($) $ in Millions	12 Months Ended
Dec. 31, 2020	Dec. 31, 2019	Dec. 31, 2018
Compensation Related Costs [Abstract]
Wages, salaries and incentive compensation	$ 207.6	$ 201.8	$ 197.2
Payroll taxes	15.6	16.0	15.6
Defined contribution and defined benefit pension plan expense (credit), net	1.0	2.0	(17.8)
Insurance and other benefit costs	25.1	21.9	22.3
Share-based compensation	6.9	8.4	12.9
Total	$ 256.2	$ 250.1	$ 230.2

Payroll taxes.

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- Definition

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

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 718
-SubTopic 10
-Section 50
-Paragraph 1
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- References

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- Definition

Amount of expense for salary, wage, profit sharing; incentive and equity-based compensation; and other employee benefit.

+ References

Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 220
-SubTopic 10
-Section S99
-Paragraph 2
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Amount of labor-related expenses classified as other.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
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Amount of cost (reversal of cost) for pension and other postretirement benefits.

+ References

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Amount of expense for salary and wage arising from service rendered by nonofficer and officer employees. Excludes allocated cost, labor-related nonsalary expense, and direct and overhead labor cost included in cost of good and service sold.

+ References

No definition available.

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