Consolidated Statements of Comprehensive Income (Unaudited) - USD ($) $ in Millions	3 Months Ended	6 Months Ended
Jun. 30, 2019	Jun. 30, 2018	Jun. 30, 2019	Jun. 30, 2018
Statement of Comprehensive Income [Abstract]
Net Income	$ 389.4	$ 390.4	$ 736.5	$ 772.0
Other Comprehensive Income (Loss) (Net of Tax and Reclassifications)
Net Unrealized Gains (Losses) on Debt Securities Available for Sale	162.4	(19.9)	248.0	(74.9)
Net Unrealized Gains (Losses) on Cash Flow Hedges	4.8	(3.5)	0.5	(7.2)
Foreign Currency Translation Adjustments	14.1	13.6	28.9	0.5
Pension and Other Postretirement Benefit Adjustments	4.2	7.4	16.5	13.1
Other Comprehensive Income	185.5	(2.4)	293.9	(68.5)
Comprehensive Income	$ 574.9	$ 388.0	$ 1,030.4	$ 703.5

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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