Property, Plant and Equipment - Components of Property, Plant and Equipment (Detail) (USD $) In Millions, unless otherwise specified	3 Months Ended
	Aug. 31, 2014	Aug. 31, 2013	May 31, 2014
Property, Plant and Equipment [Line Items]
Total property, plant and equipment	$ 1,448.0		$ 1,421.9
Accumulated depreciation	(724.7)		(705.9)
Total property, plant and equipment, net	723.3		716.0
Depreciation expense	49.7	44.9
Land and land improvements [Member}
Property, Plant and Equipment [Line Items]
Total property, plant and equipment	40.6		40.8
Buildings and leasehold improvements [Member]
Property, Plant and Equipment [Line Items]
Total property, plant and equipment	123.5		126.8
Machinery and equipment [Member]
Property, Plant and Equipment [Line Items]
Total property, plant and equipment	420.8		414.5
Instruments [Member]
Property, Plant and Equipment [Line Items]
Total property, plant and equipment	812.9		791.9
Construction in progress [Member]
Property, Plant and Equipment [Line Items]
Total property, plant and equipment	$ 50.2		$ 47.9