Accumulated Other Comprehensive Loss, net of tax Reclassifications from AOCI, net of tax (Details) (USD $) In Millions, unless otherwise specified	12 Months Ended
	Dec. 31, 2014		Dec. 31, 2013		Dec. 31, 2012
Reclassification Adjustment out of Accumulated Other Comprehensive Income on Derivatives [Line Items]
Other Comprehensive Income (Loss), Tax	$ 9.6		$ (2.4)		$ 10.3
Total Reclassification from AOCI	21.1		8.7		19.7
Foreign Currency Translation Adjustment
Reclassification Adjustment out of Accumulated Other Comprehensive Income on Derivatives [Line Items]
Reclassification from Accumulated Other Comprehensive Income, Current Period, before Tax	(0.9)		0		0
Available-for-sale Securities
Reclassification Adjustment out of Accumulated Other Comprehensive Income on Derivatives [Line Items]
Reclassification from Accumulated Other Comprehensive Income, Current Period, before Tax	0		1.4		(0.7)
Derivative Instruments
Reclassification Adjustment out of Accumulated Other Comprehensive Income on Derivatives [Line Items]
Reclassification from Accumulated Other Comprehensive Income, Current Period, before Tax	1.9		1.7		0.3
Defined Benefit and Postretirement Plans
Reclassification Adjustment out of Accumulated Other Comprehensive Income on Derivatives [Line Items]
Reclassification from Accumulated Other Comprehensive Income, Current Period, before Tax	$ 10.5	[1]	$ 10.8	[1]	$ 8.4	[1]

[1] 1These accumulated other comprehensive loss components are included in the computation of net periodic cost. See Note 12 for further information