Contractual interest rate for funds borrowed, under the debt agreement.

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 210

-SubTopic 10

-Section S99

-Paragraph 1

-Subparagraph (SX 210.5-02.22(a)(1))

-URI http://asc.fasb.org/extlink&oid=6877327&loc=d3e13212-122682

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The interest rate applicable to the portion of the carrying amount of long-term borrowings outstanding as of the balance sheet date, including current maturities, which accrues interest at a rate subject to change from time to time.

+ References

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Long-term Debt - Summary of Long-term Debt (Parenthetical) (Details) - USD ($) $ in Millions	May. 31, 2015	May. 31, 2014
Term Loan [Member]
Debt Instrument [Line Items]
Term loan, bearing interest at variable rates	2.52%
Quarterly installments of term loan, bearing interest at variable rates, amount	$ 1.3
7.125% Second-Priority Senior Secured Notes [Member]
Debt Instrument [Line Items]
Convertible subordinated debentures, bearing interest	7.125%
2.25% Convertible Subordinated Debentures [Member]
Debt Instrument [Line Items]
Convertible subordinated debentures, bearing interest	2.25%
4 1/16% Convertible Subordinated Debentures [Member]
Debt Instrument [Line Items]
Convertible subordinated debentures, bearing interest	4.0625%	4.0625%
Delayed Draw Term Loan [Member]
Debt Instrument [Line Items]
Term loan, bearing interest at variable rates	9.50%