Business Segment Information (Details) (USD $) In Millions, unless otherwise specified	3 Months Ended	6 Months Ended
Nov. 30, 2014	Nov. 30, 2013	Nov. 30, 2014 item	Nov. 30, 2013
Business Segment Information
Number of business segments			2us-gaap_NumberOfReportableSegments
Business Segment Information
Sales	$ 490.0us-gaap_SalesRevenueNet	$ 540.7us-gaap_SalesRevenueNet	$ 959.2us-gaap_SalesRevenueNet	$ 1,055.2us-gaap_SalesRevenueNet
Gross Profit	78.5us-gaap_GrossProfit	91.0us-gaap_GrossProfit	153.8us-gaap_GrossProfit	175.7us-gaap_GrossProfit
Aviation Services
Business Segment Information
Sales	377.7	424.7	741.4	818.4
Gross Profit	63.9	71.3	123.0	136.8
Technology Products
Business Segment Information
Sales	112.3	116.0	217.8	236.8
Gross Profit	$ 14.6	$ 19.7	$ 30.8	$ 38.9

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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- Details

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- Details

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