Supplemental Cash Flow Information (Details) - USD ($) $ in Millions	6 Months Ended
Nov. 30, 2018	Nov. 30, 2017
Supplemental Cash Flow Information
Interest paid	$ 4.3	$ 3.0
Income taxes paid	$ 3.0	14.8
Income tax refunds received		$ 0.1

The amount of cash paid during the current period to foreign, federal, state, and local authorities as taxes on income.

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-Publisher FASB
-Name Accounting Standards Codification
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-SubTopic 10
-Section 50
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- Definition

Amount of cash paid for interest, excluding capitalized interest, classified as operating activity. Includes, but is not limited to, payment to settle zero-coupon bond for accreted interest of debt discount and debt instrument with insignificant coupon interest rate in relation to effective interest rate of borrowing attributable to accreted interest of debt discount.

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 230
-SubTopic 10
-Section 50
-Paragraph 2
-URI http://asc.fasb.org/extlink&oid=98513485&loc=d3e4297-108586

Reference 2: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
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- Definition

The amount of cash received during the period as refunds for the overpayment of taxes.

+ References

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-Publisher FASB
-Name Accounting Standards Codification
-Topic 230
-SubTopic 10
-Section 45
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Balance Type:	debit
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- References

No definition available.

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