Segment Reporting (Restated) - Additional Information (Detail) (USD $)	9 Months Ended		3 Months Ended	9 Months Ended
May 31, 2013 Segment	Aug. 31, 2012	May 31, 2013 Carolina Starches, LLC [Member]	May 31, 2012 Carolina Starches, LLC [Member]	May 31, 2013 Carolina Starches, LLC [Member]	May 31, 2012 Carolina Starches, LLC [Member]
Segment Reporting Information [Line Items]
Number of segments	2
Consolidated assets related to the acquisition	$ 232,301,000	$ 236,179,000	$ 12,100,000		$ 12,100,000
Industrial Ingredients revenues			$ 6,800,000	$ 5,300,000	$ 18,700,000	$ 9,000,000

Sum of the carrying amounts as of the balance sheet date of all assets that are recognized. Assets are probable future economic benefits obtained or controlled by an entity as a result of past transactions or events.

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 210.5-02.18)

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

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 210

-SubTopic 10

-Section S99

-Paragraph 1

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

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

-Publisher SEC

-Name Regulation S-X (SX)

-Number 210

-Section 03

-Paragraph 12

-Article 7

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

-Publisher SEC

-Name Regulation S-X (SX)

-Number 210

-Section 02

-Paragraph 18

-Article 5

Name:	us-gaap_Assets
Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	instant