Long-Term Debt (Parenthetical) (Detail)	1 Months Ended	12 Months Ended	1 Months Ended	12 Months Ended
Aug. 25, 2011 Senior Secured Revolving Credit Facility	May 31, 2012 Senior Secured Revolving Credit Facility	Aug. 10, 2010 9.25% Senior Notes	May 31, 2012 9.25% Senior Notes
Debt Instrument [Line Items]
Credit facility expiration date	August 25, 2016	August 25, 2016
Senior notes, interest rate			9.25%	9.25%
Senior notes maturity date			2020	2020

Interest rate stated in the contractual debt agreement.

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

-Publisher SEC

-Name Regulation S-X (SX)

-Number 210

-Section 02

-Paragraph 22

-Article 5

Reference 2: 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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