Consolidated Statements of Comprehensive Income - USD ($) $ in Millions	12 Months Ended
Dec. 31, 2015	Dec. 31, 2014	Dec. 31, 2013
Statement of Comprehensive Income [Abstract]
Net Income	$ 973.8	$ 811.8	$ 731.3
Other Comprehensive Income (Loss) (Net of Tax and Reclassifications)
Net Unrealized Gains (Losses) on Securities Available for Sale	(58.6)	21.6	(95.0)
Net Unrealized (Losses) Gains on Cash Flow Hedges	1.7	(7.6)	4.3
Foreign Currency Translation Adjustments	(15.9)	(8.8)	(3.4)
Pension and Other Postretirement Benefit Adjustments	19.8	(80.6)	132.8
Other Comprehensive (Loss) Income	(53.0)	(75.4)	38.7
Comprehensive Income	$ 920.8	$ 736.4	$ 770.0

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.

Reference 1: http://www.xbrl.org/2003/role/presentationRef
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-Name Accounting Standards Codification
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-URI http://asc.fasb.org/extlink&oid=51831270

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Amount after tax, before reclassification adjustments, of unrealized holding gain (loss) on available-for-sale securities.

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