Indebtedness (Details) (USD $) In Millions, unless otherwise specified	3 Months Ended
	Jun. 30, 2014	Mar. 31, 2014
Debt Instrument [Line Items]
Short-term debt	$ 30.6	$ 32.4
Long-term debt, fair value	141.0	140.0
Line of Credit Facility [Line Items]
Available for future borrowings	214.0
Domestic Revolving Credit Facility [Member]
Line of Credit Facility [Line Items]
Amount outstanding	0	0
Maximum borrowing capacity	175.0
Expiration date	Aug. 31, 2018
Available for future borrowings	166.0
Foreign Credit Facility [Member]
Line of Credit Facility [Line Items]
Available for future borrowings	48.0
Domestic Letters of Credit [Member]
Line of Credit Facility [Line Items]
Letters of credit outstanding	9.0
6.8% Senior Notes [Member]
Debt Instrument [Line Items]
Long-term debt	$ 125.0
Stated interest rate (in hundredths)	6.80%