Accumulated Other Comprehensive Income - Tax Effects on Each Component of Other Comprehensive Income Recognized in Statements of Comprehensive Income (Detail) - USD ($) $ in Millions	3 Months Ended		6 Months Ended
	Jun. 30, 2015	Jun. 30, 2014	Jun. 30, 2015	Jun. 30, 2014
Statement of Comprehensive Income [Abstract]
Foreign currency cumulative translation adjustments, Before Tax	$ 27.8	$ (12.3)	$ (124.9)	$ 3.6
Unrealized cash flow hedge gains/(losses), Before Tax	(11.0)	(11.6)	40.7	(15.5)
Reclassification adjustments on foreign currency hedges, Before Tax	(32.7)	(6.6)	(60.7)	(11.5)
Unrealized gains/(losses) on securities, Before Tax	(0.1)	0.1	0.5	0.2
Reclassification adjustments on securities, Before Tax				(0.4)
Adjustments to prior service cost and unrecognized actuarial assumptions, Before Tax	3.0	1.9	6.2	3.8
Total Other Comprehensive Gain/(Loss), Before Tax	(13.0)	(28.5)	(138.2)	(19.8)
Foreign currency cumulative translation adjustments, Tax	0.0	0.0	0.0	0.0
Unrealized cash flow hedge gains/(losses), Tax	2.1	(3.3)	1.4	(4.1)
Reclassification adjustments on foreign currency hedges, Tax	(7.6)	(3.9)	(14.0)	(6.8)
Unrealized gains/(losses) on securities, Tax	0.0	0.0	0.0	0.0
Reclassification adjustments on securities, Tax		0.0		0.0
Adjustments to prior service cost and unrecognized actuarial assumptions, Tax	1.5	(1.7)	0.8	2.1
Total Other Comprehensive Gain/(Loss), Tax	(4.0)	(8.9)	(11.8)	(8.8)
Foreign currency cumulative translation adjustments, net of tax	27.8	(12.3)	(124.9)	3.6
Unrealized cash flow hedge gains/(losses), net of tax	(13.1)	(8.3)	39.3	(11.4)
Reclassification adjustments on foreign currency hedges, net of tax	(25.1)	(2.7)	(46.7)	(4.7)
Unrealized gains/(losses) on securities, net of tax	(0.1)	0.1	0.5	0.2
Reclassification adjustments on securities, net of tax				(0.4)
Adjustments to prior service cost and unrecognized actuarial assumptions, net of tax	1.5	3.6	5.4	1.7
Total Other Comprehensive Gain/(Loss), net of tax	$ (9.0)	$ (19.6)	$ (126.4)	$ (11.0)