Fair value of all asset derivatives designated as cash flow hedging instruments.

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 815

-SubTopic 10

-Section 50

-Paragraph 4B

-Subparagraph (c)(1)

-URI http://asc.fasb.org/extlink&oid=35706170&loc=SL5624163-113959

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Fair value of all liability derivatives designated as cash flow hedging instruments.

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Fair value, after effects of master netting arrangements, of financial asset or other contract with one or more underlyings, notional amount or payment provision or both, and the contract can be net settled by means outside the contract or delivery of an asset offset against an obligation to return collateral. Includes assets not subject to a master netting arrangement and not elected to be offset.

+ References

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 210

-SubTopic 20

-Section 55

-Paragraph 13

-URI http://asc.fasb.org/extlink&oid=36459792&loc=SL20226016-175313

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-Name Accounting Standards Codification

-Topic 210

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-Section 50

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-Publisher FASB

-Name Accounting Standards Codification

-Topic 815

-SubTopic 10

-Section 50

-Paragraph 8

-Subparagraph (a)

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Nominal or face amount used to calculate payments on the derivative liability.

+ References

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 815

-SubTopic 10

-Section 50

-Paragraph 1B

-URI http://asc.fasb.org/extlink&oid=35706170&loc=SL5580258-113959

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-Publisher FASB

-Name Accounting Standards Codification

-Topic 815

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-Name Accounting Standards Codification

-Glossary Notional Amount

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The number of derivative instruments of a particular group held by the entity.

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Derivative Instruments and Hedging Activities (Details) (USD $) In Millions, unless otherwise specified	Feb. 28, 2015	May 31, 2014
Derivative Instruments and Hedging Activities
Number of derivative financial instruments	2
Interest rate cap \| Derivatives designated as hedging instruments:
Fair value carrying amount of the Company's interest rate derivatives
Derivative Assets	$ 0.1	$ 0.1
Interest rate cap \| Derivatives designated as hedging instruments: \| Cash flow hedges
Derivative Instruments and Hedging Activities
Notional amount under revolving credit agreement	50.0
Interest rate swap \| Derivatives designated as hedging instruments:
Fair value carrying amount of the Company's interest rate derivatives
Derivative Liabilities	(2.3)	(2.8)
Interest rate swap \| Derivatives designated as hedging instruments: \| Cash flow hedges
Derivative Instruments and Hedging Activities
Notional amount under revolving credit agreement	50.0
Interest Rate Swap and Cap Agreements \| Derivatives designated as hedging instruments:
Derivative Instruments and Hedging Activities
Settlement of floating-to-fixed interest rate swap and interest rate cap agreement	$ 2.6