Allowance for Doubtful Accounts (Details) - Allowance for Doubtful Accounts - USD ($) $ in Millions	12 Months Ended
May 31, 2017	May 31, 2016	May 31, 2015
Changes in allowance for doubtful accounts
Balance, beginning of year	$ 4.0	$ 5.8	$ 6.2
Provision charged to operations	2.4	0.3	1.7
Deductions for accounts written off, net of recoveries	(0.6)	(2.1)	(1.6)
Reclassification to assets of discontinued operations			(0.1)
Balance, end of year	$ 5.8	$ 4.0	5.8
Telair Cargo Group
Changes in allowance for doubtful accounts
Sale of Telair Cargo Group			$ (0.4)

Reclassification to assets of discontinued operations.

No definition available.

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- Definition

Amount of consideration received or receivable for the disposal of assets and liabilities, including discontinued operation.

+ References

No definition available.

+ Details

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- Definition

A roll forward is a reconciliation of a concept from the beginning of a period to the end of a period.

+ References

No definition available.

+ Details

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- Definition

Total of allowances and reserves, the valuation and qualifying accounts that are either netted against the cost of an asset (in order to value it at its carrying value) or that reflect a liability established to represent expected future costs.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 235
-SubTopic 10
-Section S99
-Paragraph 4
-Subparagraph (SX 210.12-09)
-URI http://asc.fasb.org/extlink&oid=26873400&loc=d3e24092-122690

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- Definition

Amount of increase in the allowances and reserves, which consist of the valuation and qualifying accounts that are either netted against the cost of an asset or that reflect a liability established to represent expected future costs, from charges to costs and expenses.

+ References

+ Details

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- Definition

Total of the deductions in a given period to allowances and reserves, the valuation and qualifying accounts that are either netted against the cost of an asset (in order to value it at its carrying value) or that reflect a liability established to represent expected future costs, representing receivables written off as uncollectible and portions of the reserves utilized, respectively.

+ References

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