Accumulated Other Comprehensive (Loss) Income - Changes in Accumulated Other Comprehensive (Loss) Income (Details) - USD ($) $ in Millions	12 Months Ended
	Dec. 31, 2017	Dec. 31, 2016	Dec. 31, 2015
Accumulated Other Comprehensive Income (Loss), Net of Tax [Roll Forward]
Balance	$ 2,889.8	$ 2,273.3	$ 2,552.6
Other comprehensive (loss) income before reclassifications, net	233.2	200.5	(755.0)
Reclassifications, pretax	21.4	11.1	0.0
Tax (benefit) expense reclassified	(2.1)	0.0	(0.5)
Balance	2,860.0	2,889.8	2,273.3
Accumulated Other Comprehensive Income (Loss)
Accumulated Other Comprehensive Income (Loss), Net of Tax [Roll Forward]
Balance	(674.5)	(886.1)	(130.6)
Balance	(422.0)	(674.5)	(886.1)
Foreign Currency Translation Adjustments
Accumulated Other Comprehensive Income (Loss), Net of Tax [Roll Forward]
Balance	(694.7)	(899.3)	(122.2)
Other comprehensive (loss) income before reclassifications, net	241.1	204.6	(777.1)
Reclassifications, pretax	0.0	0.0	0.0
Tax (benefit) expense reclassified	0.0	0.0	0.0
Balance	(453.6)	(694.7)	(899.3)
Pension and Post-retirement Plans
Accumulated Other Comprehensive Income (Loss), Net of Tax [Roll Forward]
Balance	(18.8)	(26.3)	(14.9)
Other comprehensive (loss) income before reclassifications, net	2.5	8.3	(10.9)
Reclassifications, pretax	10.5	(0.8)	0.0
Tax (benefit) expense reclassified	(2.1)	0.0	(0.5)
Balance	(7.9)	(18.8)	(26.3)
Unrealized Gain (Loss) on Available for Sale Securities
Accumulated Other Comprehensive Income (Loss), Net of Tax [Roll Forward]
Balance	0.4	1.2	0.1
Other comprehensive (loss) income before reclassifications, net	(2.2)	(0.8)	1.1
Reclassifications, pretax	0.5	0.0	0.0
Tax (benefit) expense reclassified	0.0	0.0	0.0
Balance	(1.3)	0.4	1.2
Derivative Financial Instrument Revaluation
Accumulated Other Comprehensive Income (Loss), Net of Tax [Roll Forward]
Balance	(5.8)	(8.1)	0.0
Other comprehensive (loss) income before reclassifications, net	(4.6)	(9.6)	(8.1)
Reclassifications, pretax	10.4	11.9	0.0
Tax (benefit) expense reclassified	0.0	0.0	0.0
Balance	0.0	(5.8)	(8.1)
Non-Controlling Interests
Accumulated Other Comprehensive Income (Loss), Net of Tax [Roll Forward]
Balance	44.4	46.4	6.4
Other comprehensive (loss) income before reclassifications, net	(3.6)	(2.0)	40.0
Reclassifications, pretax	0.0	0.0	0.0
Tax (benefit) expense reclassified	0.0	0.0	0.0
Balance	$ 40.8	$ 44.4	$ 46.4