Components of Comprehensive Income, Net of Related Tax (Detail) (USD $) In Millions, unless otherwise specified	3 Months Ended		6 Months Ended
	Jun. 30, 2014	Jun. 30, 2013	Jun. 30, 2014	Jun. 30, 2013
Comprehensive Income (Loss) [Line Items]
Net income	$ 319.2	$ 291.6	$ 593.1	$ 527.7
Other comprehensive income (loss)
Unrealized (losses) gains on derivative contracts, before tax	(1.3)	10.1	0.4	13.3
Unrealized (losses) gains on derivative contracts, tax	0.8	(3.0)	0.2	(4.1)
Unrealized (losses) gains on derivative contracts, net of tax	(0.5)	7.1	0.6	9.2
Unrealized gains (losses) on marketable debt securities, before tax	2.5	(5.5)	3.7	(5.8)
Unrealized gains (losses)on marketable debt securities, tax	(0.8)	1.5	(1.0)	1.6
Unrealized gains (losses) on marketable debt securities, net of tax	1.7	(4.0)	2.7	(4.2)
Pension plans, before tax	1.1	13.0	7.5	34.3
Pension plans, tax	(0.5)	(4.4)	(2.6)	(11.1)
Pension plans, net of tax	0.6	8.6	4.9	23.2
Foreign currency translation gains (losses)	47.7	(82.6)	46.6	(178.6)
Net other comprehensive income (loss)	49.5	(70.9)	54.8	(150.4)
Comprehensive income	$ 368.7	$ 220.7	$ 647.9	$ 377.3