Income Taxes (Details) $ in Millions	3 Months Ended	9 Months Ended
Feb. 29, 2016 USD ($)	Feb. 29, 2016 USD ($)
Income Tax Disclosure [Abstract]
Unrecognized tax benefits, period increase (decrease)	$ (0.4)	$ 0.7
Unrecognized tax benefits, increase in accrued interest		0.2
Decrease in unrecognized tax benefit	$ 3.1	$ 3.1

Decrease in Unrecognized Tax Benefits is Reasonably Possible Within Fifteen Months

No definition available.

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- References

No definition available.

+ Details

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- Definition

Amount of interest expense for an underpayment of income taxes.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 740
-SubTopic 10
-Section 50
-Paragraph 15
-Subparagraph (c)
-URI http://asc.fasb.org/extlink&oid=6907707&loc=d3e32718-109319

+ Details

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- Definition

The net amount of all increases and decreases in unrecognized tax benefits for the period.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 740
-SubTopic 10
-Section 50
-Paragraph 15A
-Subparagraph (a)
-URI http://asc.fasb.org/extlink&oid=6907707&loc=SL6600010-109319

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