Segment Reporting - Assets by Segment (Detail) (USD $) In Thousands, unless otherwise specified	Nov. 30, 2012	Aug. 31, 2012
Segment Reporting, Asset Reconciling Item [Line Items]
Total assets	$ 232,453	$ 236,179
Industrial Ingredients [Member]
Segment Reporting, Asset Reconciling Item [Line Items]
Total assets	140,839	143,039
Food Ingredients [Member]
Segment Reporting, Asset Reconciling Item [Line Items]
Total assets	63,742	63,949
Corporate and Other [Member]
Segment Reporting, Asset Reconciling Item [Line Items]
Total assets	$ 27,872	$ 29,191