Debt (Schedule Of Debt) (Details) - USD ($) $ in Millions	Dec. 31, 2018	Dec. 31, 2017
Debt Instrument [Line Items]
Principal debt outstanding	$ 825.6	$ 858.1
Unamortized debt financing costs	(5.8)	(7.9)
Less current portion and short-term debt	55.0	32.5
Long-term debt, less current installments	$ 764.8	$ 817.7
Principal debt outstanding, Weighted average year- end interest rate	4.33%	3.43%
Term Loan A Due 2021 [Member]
Debt Instrument [Line Items]
Principal debt outstanding	$ 547.5	$ 577.5
Principal debt outstanding, Weighted average year- end interest rate	4.00%	3.24%
Term Loan B Due 2023 [Member]
Debt Instrument [Line Items]
Principal debt outstanding	$ 243.1	$ 245.6
Principal debt outstanding, Weighted average year- end interest rate	5.39%	4.25%
Tax Exempt Bonds Due 2041 [Member]
Debt Instrument [Line Items]
Principal debt outstanding	$ 35.0	$ 35.0
Principal debt outstanding, Weighted average year- end interest rate	1.47%	0.79%
Current Portion And Short-Term Debt [Member]
Debt Instrument [Line Items]
Less current portion and short-term debt	$ 55.0	$ 32.5
Current portion and short-term debt, Weighted average year-end interest rate	4.07%	3.32%
Long-term Debt [Member]
Debt Instrument [Line Items]
Long-term debt	$ 819.8	$ 850.2
Principal debt outstanding, Weighted average year- end interest rate	4.33%	3.43%
Long-Term Debt, Less Current Portion [Member]
Debt Instrument [Line Items]
Long-term debt, less current installments	$ 764.8	$ 817.7
Long-term debt, Weighted average year-end interest rate	4.35%	3.43%

Amount, before unamortized (discount) premium and debt issuance costs, of long-term debt. Includes, but is not limited to, notes payable, bonds payable, commercial loans, mortgage loans, convertible debt, subordinated debt and other types of debt.

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