Financing Arrangements - Long-term Debt (Details) - USD ($) $ in Millions	12 Months Ended
	Dec. 31, 2016	Dec. 31, 2015	Dec. 31, 2014
Debt Instrument [Line Items]
Operating Leases, Future Minimum Payments Due, Next Twelve Months	$ 26.2
Operating Leases, Rent Expense, Net	30.0	$ 33.5	$ 33.0
Long-term Debt, Maturities, Repayments of Principal in Next Twelve Months	5.0
Long-term Debt	640.0	594.5
Long-term Debt, Current Maturities	5.0	15.1
Long-term debt
Long-term debt	635.0	579.4
Long-term Debt, Maturities, Repayments of Principal in Year Two	48.9
Long-term Debt, Maturities, Repayments of Principal in Year Three	0.0
Long-term Debt, Maturities, Repayments of Principal in Year Four	83.8
Long-term Debt, Maturities, Repayments of Principal in Year Five	1.9
Long-term Debt, Maturities, Repayments of Principal after Year Five	500.4
Operating Leases, Future Minimum Payments, Due in Two Years	21.0
Operating Leases, Future Minimum Payments, Due in Three Years	16.8
Operating Leases, Future Minimum Payments, Due in Four Years	13.5
Operating Leases, Future Minimum Payments, Due in Five Years	8.8
Operating Leases, Future Minimum Payments, Due Thereafter	5.5
Series A Medium Term Note [Member]
Debt Instrument [Line Items]
Long-term Debt	159.5	174.4
Senior Unsecured Notes - 3.875% [Member]
Debt Instrument [Line Items]
Long-term Debt	$ 345.9	344.8
Long-term debt
Debt Instrument, Interest Rate, Stated Percentage	3.875%
Senior Unsecured Notes - Variable Rate [Member]
Debt Instrument [Line Items]
Long-term Debt	$ 83.8	$ 75.2
Long-term debt
Debt Instrument, Interest Rate, Stated Percentage	1.50%	1.45%
Other Long Term Debt [Member]
Debt Instrument [Line Items]
Long-term Debt	$ 1.9	$ 0.1
Line of Credit [Member] | Line of Credit Accounts Receivable Securitization [Member]
Debt Instrument [Line Items]
Long-term Debt	$ 48.9	$ 0.0