Accumulated Other Comprehensive Income (Loss) - Accumulated other comprehensive income (loss) and related components (Detail) (USD $) In Millions, unless otherwise specified	6 Months Ended
	Nov. 30, 2014
Accumulated Other Comprehensive Income (Loss), Net Of Tax [Roll Forward]
Beginning of period	$ 39.3
OCI before reclassifications	(184.9)
Reclassifications	4.6
End of period	(141.0)
Unrecognized Actuarial Gains (Losses) [Member]
Accumulated Other Comprehensive Income (Loss), Net Of Tax [Roll Forward]
Beginning of period	(11.0)
OCI before reclassifications	1.9
Reclassifications	0
End of period	(9.1)
Foreign Currency Translation Adjustments [Member]
Accumulated Other Comprehensive Income (Loss), Net Of Tax [Roll Forward]
Beginning of period	62.6
OCI before reclassifications	(185.5)
Reclassifications	0
End of period	(122.9)
Unrealized Gain (Loss) on Interest Rate Swaps [Member]
Accumulated Other Comprehensive Income (Loss), Net Of Tax [Roll Forward]
Beginning of period	(12.3)
OCI before reclassifications	(1.4)
Reclassifications	4.6
End of period	(9.1)
Unrealized Gain (Loss) on Available-For-Sale Securities [Member]
Accumulated Other Comprehensive Income (Loss), Net Of Tax [Roll Forward]
Beginning of period	0
OCI before reclassifications	0.1
Reclassifications	0
End of period	$ 0.1