Comprehensive Earnings (Accumulated Other Comprehensive Loss) (Details) - USD ($) $ in Millions	3 Months Ended		9 Months Ended		12 Months Ended
	Sep. 30, 2016	Sep. 30, 2015	Sep. 30, 2016	Sep. 30, 2015	Dec. 31, 2015	Jun. 30, 2016	Jun. 30, 2015	Dec. 31, 2014
Accumulated Other Comprehensive Income (Loss) [Line Items]
Net unrealized gain (loss) on marketable securities, net of tax	$ 19.5		$ 19.5		$ (1.0)
Net unrecognized losses and prior service cost related to defined benefit plans, net of tax	(15.1)		(15.1)		(14.9)
Net unrecognized losses on derivatives in net investment hedging relationships, net of tax		$ (84.2)		$ (67.4)
Foreign currency translation adjustment	(1,084.8)		(1,084.8)		(1,730.3)
Accumulated other comprehensive loss	(1,120.4)		(1,120.4)		(1,764.3)
Cash Flow Hedging
Accumulated Other Comprehensive Income (Loss) [Line Items]
Net unrecognized losses on derivatives in net investment hedging relationships, net of tax	22.8	(84.2)	(22.9)	(67.4)
Net Investment Hedging
Accumulated Other Comprehensive Income (Loss) [Line Items]
Net unrecognized losses on derivatives in net investment hedging relationships, net of tax	(10.4)	0.0	(10.4)	0.0
Gains and Losses on Derivatives
Accumulated Other Comprehensive Income (Loss) [Line Items]
Net unrecognized losses on derivatives in cash flow hedging relationships, net of tax		$ (71.0)		$ (71.0)			$ (17.6)	$ (28.4)
Gains and Losses on Derivatives | Cash Flow Hedging
Accumulated Other Comprehensive Income (Loss) [Line Items]
Net unrecognized losses on derivatives in cash flow hedging relationships, net of tax	(31.9)		(31.9)		(18.1)	$ (46.7)
Gains and Losses on Derivatives | Net Investment Hedging
Accumulated Other Comprehensive Income (Loss) [Line Items]
Net unrecognized losses on derivatives in cash flow hedging relationships, net of tax	(8.1)		$ (8.1)		0.0	$ 0.0
Net unrecognized losses on derivatives in net investment hedging relationships, net of tax	$ (8.1)				$ 0.0