Changes in Accumulated Other Comprehensive Income (loss) by Component (Detail) (USD $) In Millions, unless otherwise specified	12 Months Ended
	Dec. 31, 2014	Dec. 31, 2013	Dec. 31, 2012
Accumulated Other Comprehensive Income (Loss) [Line Items]
Beginning balance	$ 8.7	$ (159.5)
Recorded into AOCI	(584.4)	164.3
Reclassified out of AOCI	(4.1)	3.9
Net other comprehensive (loss) income	(588.5)	168.2	59.5
Ending balance	(579.8)	8.7	(159.5)
Derivative Contracts
Accumulated Other Comprehensive Income (Loss) [Line Items]
Beginning balance	(15.1)	(27.2)
Recorded into AOCI	20.0	36.9
Reclassified out of AOCI	(18.4)	(24.8)
Net other comprehensive (loss) income	1.6	12.1
Ending balance	(13.5)	(15.1)
Marketable Debt Securities
Accumulated Other Comprehensive Income (Loss) [Line Items]
Beginning balance	1.7	6.6
Recorded into AOCI	4.2	(6.1)
Reclassified out of AOCI	(0.6)	1.2
Net other comprehensive (loss) income	3.6	(4.9)
Ending balance	5.3	1.7
Pension Plan
Accumulated Other Comprehensive Income (Loss) [Line Items]
Beginning balance	(262.2)	(496.5)
Recorded into AOCI	(185.8)	204.8
Reclassified out of AOCI	14.9	29.5
Net other comprehensive (loss) income	(170.9)	234.3
Ending balance	(433.1)	(262.2)
Foreign Currency Translation
Accumulated Other Comprehensive Income (Loss) [Line Items]
Beginning balance	284.3	357.6
Recorded into AOCI	(422.8)	(71.3)
Reclassified out of AOCI		(2.0)
Net other comprehensive (loss) income	(422.8)	(73.3)
Ending balance	$ (138.5)	$ 284.3