Consolidated Statements of Comprehensive Income (Unaudited) - USD ($) $ in Millions	3 Months Ended		9 Months Ended
	Sep. 30, 2017	Sep. 30, 2016	Sep. 30, 2017	Sep. 30, 2016
Other Comprehensive Income (Loss), Net of Tax [Abstract]
Net Income	$ 219.6	$ 131.5	$ 556.2	$ 294.5
Other comprehensive income, net of tax:
Foreign currency translation adjustments	11.1	(2.2)	54.6	16.3
Net unrealized gains on available for sale securities	3.9	5.6	10.6	20.3
Changes in benefit plans net gain (loss) and prior service (cost)/credit	0.1	0.1	1.6	1.3
Other comprehensive income, net of tax	15.1	3.5	66.8	37.9
Comprehensive income	$ 234.7	$ 135.0	$ 623.0	$ 332.4