Accumulated Other Comprehensive Income - Changes in Components of Other Comprehensive Income, Net of Tax (Detail) $ in Millions	6 Months Ended
	Jun. 30, 2015 USD ($)
Other Comprehensive Income Loss [Line Items]
Accumulated Other Comprehensive Income, Beginning Balance	$ 85.9
Accumulated Other Comprehensive Income, Ending Balance	(40.5)
Foreign Currency Translation [Member]
Other Comprehensive Income Loss [Line Items]
Accumulated Other Comprehensive Income, Beginning Balance	159.6
OCI before reclassifications	(124.9)
Accumulated Other Comprehensive Income, Ending Balance	34.7
Unrealized Gains on Securities [Member]
Other Comprehensive Income Loss [Line Items]
Accumulated Other Comprehensive Income, Beginning Balance	(0.4)
OCI before reclassifications	0.5
Accumulated Other Comprehensive Income, Ending Balance	0.1
Defined Benefit Plan Items [Member]
Other Comprehensive Income Loss [Line Items]
Accumulated Other Comprehensive Income, Beginning Balance	(143.4)
Reclassifications	5.4
Accumulated Other Comprehensive Income, Ending Balance	(138.0)
Cash Flow Hedges [Member]
Other Comprehensive Income Loss [Line Items]
Accumulated Other Comprehensive Income, Beginning Balance	70.1
OCI before reclassifications	39.3
Reclassifications	(46.7)
Accumulated Other Comprehensive Income, Ending Balance	$ 62.7