Reclassification Adjustments out of Accumulated Other Comprehensive Income (Loss) (Detail) (USD $) In Millions, unless otherwise specified	12 Months Ended
	Dec. 31, 2014	Dec. 31, 2013	Dec. 31, 2012
Available for Sale Investment Securities | Realized (Gains) Losses on Securities Available for Sale | Investment Security Gains (Losses), net
Reclassification Adjustment out of Accumulated Other Comprehensive Income [Line Items]
Gross Reclassification Adjustment	$ 0.1	$ 1.6	$ (13.9)
CASH FLOW HEDGES | Foreign Exchange Contracts | Other Operating Income/Expense
Reclassification Adjustment out of Accumulated Other Comprehensive Income [Line Items]
Gross Reclassification Adjustment	(4.0)	4.7	4.8
Pension and Other Postretirement Benefit Adjustments
Reclassification Adjustment out of Accumulated Other Comprehensive Income [Line Items]
Gross Reclassification Adjustment	25.2	46.1	33.9
Pension and Other Postretirement Benefit Adjustments | Employee Benefits
Reclassification Adjustment out of Accumulated Other Comprehensive Income [Line Items]
Amortization of Net Actuarial (Gains) Losses	25.1	49.0	38.8
Amortization of Prior Service Cost	$ 0.1	$ (2.9)	$ (4.9)