Lines of Credit and Financing Arrangements (Outstanding Debt Obligations) (Details) - USD ($) $ in Millions	Jun. 30, 2019	Dec. 31, 2018
Current maturities of long-term debt:
Finance lease obligations	$ 6.6	$ 3.5
Debt issuance costs	(0.6)	(0.7)
Total current maturities of long-term debt	311.0	300.8
Long-Term Debt:
Finance lease obligations	23.4	15.7
Debt issuance costs	(2.6)	(3.2)
Total long-term debt	1,155.8	740.5
Total debt	1,466.8	1,041.3
Domestic Credit Facility [Member]
Current maturities of long-term debt:
Domestic credit facility and senior unsecured notes	15.0	30.0
Long-Term Debt:
Domestic credit facility and senior unsecured notes	785.0	378.0
Asset Securitization [Member]
Current maturities of long-term debt:
Finance lease obligations	290.0	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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