Segment Reporting - Additional Information (Detail) (USD $)	3 Months Ended
	Nov. 30, 2012 Segment	Aug. 31, 2012
Segment Reporting Information [Line Items]
Number of segments	2
Consolidated assets related to the acquisition	$ 232,453,000	$ 236,179,000
Carolina Starches, LLC [Member]
Segment Reporting Information [Line Items]
Consolidated assets related to the acquisition	11,200,000
Carolina Starches, LLC [Member] | Australia and New Zealand Discontinued Operations [Member]
Segment Reporting Information [Line Items]
Industrial Ingredients revenues	$ 5,300,000