Consolidated Statement of Comprehensive Income (USD $) In Millions, unless otherwise specified	12 Months Ended
Dec. 31, 2014	Dec. 31, 2013	Dec. 31, 2012
Net Income	$ 811.8us-gaap_NetIncomeLoss	$ 731.3us-gaap_NetIncomeLoss	$ 687.3us-gaap_NetIncomeLoss
Other Comprehensive Income (Loss) (Net of Tax and Reclassifications)
Net Unrealized Gains (Losses) on Securities Available for Sale	21.6	(95.0)	61.2
Net Unrealized (Losses) Gains on Cash Flow Hedges	(7.6)	4.3	5.6
Foreign Currency Translation Adjustments	(8.8)	(3.4)	20.0
Pension and Other Postretirement Benefit Adjustments	(80.6)	132.8	(24.2)
Other Comprehensive (Loss) Income	(75.4)	38.7	62.6
Comprehensive Income	$ 736.4us-gaap_ComprehensiveIncomeNetOfTax	$ 770.0us-gaap_ComprehensiveIncomeNetOfTax	$ 749.9us-gaap_ComprehensiveIncomeNetOfTax

Amount after tax of increase (decrease) in equity from transactions and other events and circumstances from net income and other comprehensive income, attributable to parent entity. Excludes changes in equity resulting from investments by owners and distributions to owners.

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