Consolidated Statements of Comprehensive Income (Unaudited) - USD ($) $ in Millions	3 Months Ended	6 Months Ended
Jun. 30, 2016	Jun. 30, 2015	Jun. 30, 2016	Jun. 30, 2015
Statement of Comprehensive Income [Abstract]
Net Income	$ 260.7	$ 269.2	$ 502.5	$ 499.9
Other Comprehensive Income (Loss) (Net of Tax and Reclassifications)
Net Unrealized Gains (Losses) on Securities Available for Sale	33.5	(22.4)	108.2	31.7
Net Unrealized Gains (Losses) on Cash Flow Hedges	0.5	3.2	6.6	2.1
Foreign Currency Translation Adjustments	6.3	5.8	10.2	(0.1)
Pension and Other Postretirement Benefit Adjustments	4.0	6.1	8.1	12.3
Other Comprehensive Income (Loss)	44.3	(7.3)	133.1	46.0
Comprehensive Income	$ 305.0	$ 261.9	$ 635.6	$ 545.9

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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