Segment Reporting - Net Sales by Product Category (Detail) (USD $) In Millions, unless otherwise specified	3 Months Ended
	Aug. 31, 2014 reportable_segment	Aug. 31, 2013
Revenues from External Customers and Long-Lived Assets [Line Items]
Number of reportable segments	1
Net sales by product:
Net sales	$ 774.8	$ 730.7
Knees [Member]
Net sales by product:
Net sales	234.7	225.1
Hips [Member]
Net sales by product:
Net sales	155.3	149.7
S.E.T. [Member]
Net sales by product:
Net sales	154.5	149.5
Spine & Bone Healing [Member]
Net sales by product:
Net sales	122.8	101.6
Dental [Member]
Net sales by product:
Net sales	53.7	53.9
Cement, Biologics & Other [Member]
Net sales by product:
Net sales	$ 53.8	$ 50.9