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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

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- Definition Decrease in Unrecognized Tax Benefits is Reasonably Possible Within Fifteen Months + 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 + Details
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