Fair Value Measurements (Details) (Recurring basis, USD $) In Thousands, unless otherwise specified	Aug. 31, 2013	Aug. 31, 2012
Total
Fair value measurements
Restricted investments	$ 1,094	$ 874
Long-term debt	64,400	70,000
Quoted prices in active markets (Level 1)
Fair value measurements
Restricted investments	1,094	874
Significant other observable inputs (Level 2)
Fair value measurements
Long-term debt	$ 64,400	$ 70,000

The aggregate value of all restricted investments.

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 946

-SubTopic 320

-Section S99

-Paragraph 4

-Subparagraph (SX 210.12-12C.9(c))

-URI http://asc.fasb.org/extlink&oid=6955306&loc=d3e611225-123010

Reference 2: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 946

-SubTopic 320

-Section S99

-Paragraph 1

-Subparagraph (SX 210.12-12.6(c))

-URI http://asc.fasb.org/extlink&oid=6955306&loc=d3e611133-123010

Reference 3: http://www.xbrl.org/2003/role/presentationRef

-Publisher SEC

-Name Regulation S-X (SX)

-Number 210

-Section 12C

-Paragraph 9

-Subparagraph c

-Article 12

Reference 4: http://www.xbrl.org/2003/role/presentationRef

-Publisher SEC

-Name Regulation S-X (SX)

-Number 210

-Section 12

-Paragraph 6

-Subparagraph c

-Article 12

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