Debt (Schedule Of Debt) (Details) - USD ($) $ in Millions	Dec. 31, 2021	Dec. 31, 2020
Debt Instrument [Line Items]
Principal debt outstanding	$ 633.7	$ 718.7
Unamortized debt financing costs	2.3	3.2
Current installments of long-term debt	25.0	25.0
Long-term debt, less current installments	606.4	690.5
Revolving Credit Facility Due 2024 [Member]
Debt Instrument [Line Items]
Principal debt outstanding	165.0	225.0
Term Loan A Due 2024 [Member]
Debt Instrument [Line Items]
Principal debt outstanding	468.7	493.7
Long-term Debt [Member]
Debt Instrument [Line Items]
Long-term debt	631.4	715.5
Short-term Debt [Member]
Debt Instrument [Line Items]
Current installments of long-term debt	25.0	25.0
Long-Term Debt, Less Current Portion [Member]
Debt Instrument [Line Items]
Long-term debt, less current installments	$ 606.4	$ 690.5

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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