Debt (Schedule Of Debt) (Details) - USD ($) $ in Millions	Dec. 31, 2020	Dec. 31, 2019
Debt Instrument [Line Items]
Principal debt outstanding	$ 718.7	$ 615.0
Unamortized debt financing costs	(3.2)	(4.2)
Current installments of long-term debt	25.0	6.3
Long-term debt, less current installments	690.5	604.5
Revolving Credit Facility Due 2024 [Member]
Debt Instrument [Line Items]
Principal debt outstanding	225.0	115.0
Term Loan A Due 2024 [Member]
Debt Instrument [Line Items]
Principal debt outstanding	493.7	500.0
Long-term Debt [Member]
Debt Instrument [Line Items]
Long-term debt	715.5	610.8
Short-term Debt
Debt Instrument [Line Items]
Current installments of long-term debt	25.0	6.3
Long-Term Debt, Less Current Portion [Member]
Debt Instrument [Line Items]
Long-term debt, less current installments	$ 690.5	$ 604.5

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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