Consolidated Statements of Comprehensive Income - USD ($) $ in Millions	12 Months Ended
Dec. 31, 2018	Dec. 31, 2017	Dec. 31, 2016
Statement of Comprehensive Income [Abstract]
Net Income	$ 1,556.4	$ 1,199.0	$ 1,032.5
Other Comprehensive Income (Loss) (Net of Tax and Reclassifications)
Net Unrealized (Losses) Gains on Debt Securities Available for Sale	(22.3)	(42.4)	(1.4)
Net Unrealized Gains (Losses) on Cash Flow Hedges	(1.4)	(1.6)	9.1
Foreign Currency Translation Adjustments	22.2	16.7	(0.9)
Pension and Other Postretirement Benefit Adjustments	(12.6)	(17.0)	(4.1)
Other Comprehensive Income (Loss)	(14.1)	(44.3)	2.7
Comprehensive Income	$ 1,542.3	$ 1,154.7	$ 1,035.2

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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