Lines of Credit and Financing Arrangements (Outstanding Debt Obligations) (Details) - USD ($) $ in Millions	Mar. 31, 2019	Dec. 31, 2018
Current maturities of long-term debt:
Finance lease obligations	$ 6.3	$ 3.5
Debt issuance costs	(0.7)	(0.7)
Total current maturities of long-term debt	237.6	300.8
Long-Term Debt:
Finance lease obligations	22.3	15.7
Debt issuance costs	(2.8)	(3.2)
Total long-term debt	1,059.0	740.5
Total debt	1,296.6	1,041.3
Domestic Credit Facility [Member]
Current maturities of long-term debt:
Domestic credit facility and senior unsecured notes	7.5	30.0
Long-Term Debt:
Domestic credit facility and senior unsecured notes	689.5	378.0
Asset Securitization [Member]
Current maturities of long-term debt:
Finance lease obligations	224.5	268.0
Senior Unsecured Notes [Member]
Long-Term Debt:
Domestic credit facility and senior unsecured notes	$ 350.0	$ 350.0

Amount of capital lease obligation due within one year or the normal operating cycle, if longer.

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