Financing Arrangements (Details 1) - USD ($) $ in Millions	Jun. 30, 2016	Dec. 31, 2015
Long-term debt
Total Long-term debt	$ 619.2	$ 594.5
Less current maturities	15.0	15.1
Long-term debt	604.2	579.4
Senior Unsecured Notes - 3.875% [Member]
Long-term debt
Total Long-term debt	345.3	344.8
Senior Unsecured Notes - Variable Rate [Member]
Debt Instrument [Line Items]
Line of Credit Facility, Remaining Borrowing Capacity	461.6
Long-term debt
Total Long-term debt	38.4	75.2
Series A Medium Term Note [Member]
Long-term debt
Total Long-term debt	174.5	174.4
Other Long Term Debt [Member]
Long-term debt
Total Long-term debt	0.0	0.1
Line of Credit Accounts Receivable Securitization [Member]
Debt Instrument [Line Items]
Line of Credit Facility, Remaining Borrowing Capacity	13.4
Line of Credit Accounts Receivable Securitization [Member] | Line of Credit [Member]
Long-term debt
Total Long-term debt	$ 61.0	$ 0.0