Lines of Credit and Financing Arrangements (Outstanding Debt Obligations) (Details) - USD ($) $ in Millions	Dec. 31, 2022	Dec. 31, 2021
Current maturities of long-term debt:
Finance lease obligations	$ 11.2	$ 11.3
Senior unsecured notes	710.6	11.3
Long-Term Debt:
Asset securitization program	0.0	250.0
Finance lease obligations	28.3	29.0
Total long-term debt	814.2	1,226.5
Debt Issuance Cost, Gross, Noncurrent	(6.1)	(9.0)
Total debt	1,524.8	1,237.8
Domestic Credit Facility [Member]
Current maturities of long-term debt:
Debt issuance costs	(0.6)	0.0
Senior unsecured notes	350.0	0.0
Long-Term Debt:
Total long-term debt	192.0	6.5
Asset Securitization [Member]
Current maturities of long-term debt:
Asset securitization program	350.0	0.0
Senior Unsecured Notes [Member]
Long-Term Debt:
Total long-term debt	$ 600.0	$ 950.0

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

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