Accumulated Other Comprehensive Income (Loss) (Reclassification Adjustment Out of Accumulated Other Comprehensive Income (Loss)) (Details) - USD ($) $ in Millions	3 Months Ended	9 Months Ended
	Sep. 30, 2015	Sep. 30, 2015
Securities Available for Sale | Realized Losses on Securities Available for Sale | Investment Security Gains (Losses), net
Reclassification Adjustment out of Accumulated Other Comprehensive Income [Line Items]
Gross Reclassification Adjustment	$ 0.0	$ 0.3
Realized Losses on Cash Flow Hedges | Foreign Exchange Contracts | Other Operating Income/Expense
Reclassification Adjustment out of Accumulated Other Comprehensive Income [Line Items]
Gross Reclassification Adjustment	0.1	2.4
Pension and Other Postretirement Benefit Adjustments
Reclassification Adjustment out of Accumulated Other Comprehensive Income [Line Items]
Gross Reclassification Adjustment	9.6	28.8
Pension and Other Postretirement Benefit Adjustments | Employee Benefits
Reclassification Adjustment out of Accumulated Other Comprehensive Income [Line Items]
Amortization of Net Actuarial (Gains) Losses	9.7	29.0
Amortization of Prior Service Cost	$ (0.1)	$ (0.2)