Allowance for Doubtful Accounts (Details) - Allowance for Doubtful Accounts - USD ($) $ in Millions	12 Months Ended
May 31, 2018	May 31, 2017	May 31, 2016
Changes in allowance for doubtful accounts
Balance, beginning of year	$ 4.9	$ 3.3	$ 4.8
Provision charged to operations	0.5	2.1	0.3
Recoveries, deductions for accounts written off and other reclassifications	2.1	(0.5)	(1.8)
Balance, end of year	$ 7.5	$ 4.9	$ 3.3

The amount of recoveries, deductions, and other reclassifications to valuation allowances and reserves.

No definition available.

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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

+ Details

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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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- Details

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