Changes in Accumulated Other Comprehensive Income (Loss) by Component (Detail) - USD ($) $ in Millions		3 Months Ended
		Mar. 31, 2018	Mar. 31, 2017
Accumulated Other Comprehensive Income (Loss) [Line Items]
Beginning balance	[1]	$ 8,050.5
Recorded into AOCI		58.7	$ 29.3
Reclassified out of AOCI		16.6	40.8
Net other comprehensive (loss) income		75.3	70.1
Ending balance		8,567.3
Derivative Contracts
Accumulated Other Comprehensive Income (Loss) [Line Items]
Beginning balance		1.2	(4.3)
Recorded into AOCI		(11.8)	(45.9)
Reclassified out of AOCI		9.3	36.3
Net other comprehensive (loss) income		(2.5)	(9.6)
Ending balance		(1.3)	(13.9)
Marketable Debt Securities
Accumulated Other Comprehensive Income (Loss) [Line Items]
Beginning balance		(1.8)	(0.3)
Recorded into AOCI		(1.7)	2.3
Reclassified out of AOCI		(0.3)	(0.2)
Net other comprehensive (loss) income		(2.0)	2.1
Ending balance		(3.8)	1.8
Pension Plans
Accumulated Other Comprehensive Income (Loss) [Line Items]
Beginning balance		(375.6)	(414.1)
Recorded into AOCI		(5.6)	(2.1)
Reclassified out of AOCI		7.6	4.7
Net other comprehensive (loss) income		2.0	2.6
Ending balance		(373.6)	(411.5)
Foreign Currency Translation
Accumulated Other Comprehensive Income (Loss) [Line Items]
Beginning balance		(417.4)	(709.4)
Recorded into AOCI		77.8	75.0
Net other comprehensive (loss) income		77.8	75.0
Ending balance		(339.6)	(634.4)
Accumulated Other Comprehensive Income (Loss)
Accumulated Other Comprehensive Income (Loss) [Line Items]
Beginning balance		(793.6)	(1,128.1)
Ending balance		$ (718.3)	$ (1,058.0)

[1] The December 31, 2017 consolidated balance sheet has been derived from audited financial statements.