Business Segment Information (Details) (USD $) In Millions, unless otherwise specified	3 Months Ended
	Aug. 31, 2012 item	Aug. 31, 2011
Business Segment Information
Number of business segments	4
Business Segment Information
Net sales	$ 550.5	$ 485.5
Gross profit	90.3	75.7
Aviation Supply Chain
Business Segment Information
Net sales	148.7	161.1
Gross profit	23.7	26.2
Government and Defense Services
Business Segment Information
Net sales	150.6	150.0
Gross profit	25.9	27.4
Maintenance, Repair and Overhaul
Business Segment Information
Net sales	105.5	93.2
Gross profit	13.0	10.2
Structures and Systems
Business Segment Information
Net sales	145.7	81.2
Gross profit	$ 27.7	$ 11.9