Business Segment Information (Details) - USD ($) $ in Millions	3 Months Ended	9 Months Ended
Feb. 29, 2016	Feb. 28, 2015	Feb. 29, 2016	Feb. 28, 2015
Business Segment Information
Sales	$ 402.8	$ 380.1	$ 1,204.4	$ 1,178.5
Gross Profit	58.3	50.1	172.7	179.7
Aviation Services
Business Segment Information
Sales	349.2	318.4	1,024.6	955.9
Gross Profit	58.6	50.7	166.7	152.8
Expeditionary Services
Business Segment Information
Sales	53.6	61.7	179.8	222.6
Gross Profit	$ (0.3)	$ (0.6)	$ 6.0	$ 26.9

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

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 210.5-03.1,2)
-URI http://asc.fasb.org/extlink&oid=26872669&loc=d3e20235-122688

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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

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Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table.

+ References

No definition available.

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