Supplemental Cash Flow Information (Details) (USD $) In Millions, unless otherwise specified	3 Months Ended
Aug. 31, 2013	Aug. 31, 2012
Supplemental Cash Flow Information
Interest paid	$ 14.0	$ 10.6
Income taxes paid	2.5	3.1
Income tax refunds received	$ 6.5	$ 5.5

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

Reference 1: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 230

-SubTopic 10

-Section 50

-Paragraph 2

-URI http://asc.fasb.org/extlink&oid=6367179&loc=d3e4297-108586

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The amount of cash paid for interest during the period.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 230

-SubTopic 10

-Section 50

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-URI http://asc.fasb.org/extlink&oid=6367179&loc=d3e4297-108586

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

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 230

-SubTopic 10

-Section 50

-Paragraph 2

-URI http://asc.fasb.org/extlink&oid=6367179&loc=d3e4297-108586

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