Business Segment Information (Details) (USD $) In Millions, unless otherwise specified	3 Months Ended	6 Months Ended
Nov. 30, 2013	Nov. 30, 2012	Nov. 30, 2013 item	Nov. 30, 2012
Business Segment Information
Number of business segments			2
Business Segment Information
Sales	$ 540.7	$ 512.8	$ 1,055.2	$ 1,063.3
Gross Profit	91.0	87.4	175.7	177.7
Aviation Services
Business Segment Information
Sales	424.7	390.8	818.4	789.0
Gross Profit	71.3	67.4	136.8	128.8
Technology Products
Business Segment Information
Sales	116.0	122.0	236.8	274.3
Gross Profit	$ 19.7	$ 20.0	$ 38.9	$ 48.9

Aggregate revenue less cost of goods and services sold or operating expenses directly attributable to the revenue generation activity.

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- Definition

Number of segments reported by the entity. A reportable segment is a component of an entity for which there is an accounting requirement to report separate financial information on that component in the entity's financial statements.

+ References

No definition available.

+ Details

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- Definition

Total revenue from sale of goods and services rendered during the reporting period, in the normal course of business, reduced by sales returns and allowances, and sales discounts.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 225

-SubTopic 10

-Section S99

-Paragraph 2

-Subparagraph (SX 210.5-03.1)

-URI http://asc.fasb.org/extlink&oid=26872669&loc=d3e20235-122688

Reference 2: http://www.xbrl.org/2003/role/presentationRef

-Publisher SEC

-Name Regulation S-X (SX)

-Number 210

-Section 03

-Paragraph 1

-Article 5

+ Details

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- Details

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