Lines of Credit and Financing Arrangements (Outstanding Debt Obligations) (Details) - USD ($) $ in Millions	Dec. 31, 2021	Dec. 31, 2020
Current maturities of long-term debt:
Finance lease obligations	$ 11.3	$ 10.1
Domestic credit facility	11.3	9.9
Long-Term Debt:
Asset Securitization Program	250.0	0.0
Finance lease obligations	29.0	29.3
Total long-term debt	1,226.5	970.7
Debt Issuance Cost, Gross, Noncurrent	(9.0)	(8.6)
Total debt	1,237.8	980.6
Domestic Credit Facility [Member]
Current maturities of long-term debt:
Debt issuance costs	0.0	(0.2)
Long-Term Debt:
Total long-term debt	6.5	0.0
Asset Securitization [Member]
Current maturities of long-term debt:
Asset securitization program	0.0	0.0
Senior Unsecured Notes [Member]
Long-Term Debt:
Total long-term debt	$ 950.0	$ 950.0

Amount of short-term and long-term debt and lease obligation.

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