Asset Impairments (Details) (USD $)	12 Months Ended
	Aug. 31, 2012	Aug. 31, 2011	Aug. 31, 2010
Property, Plant and Equipment
Asset impairment	$ 3,392,000	$ 8,150,000	$ 5,668,000
Italy Plan [Member]
Property, Plant and Equipment
Asset impairment	2,700,000
Fair value of property, plant and equipment	2,900,000
Americas Engineered Plastics Plan [Member]
Property, Plant and Equipment
Asset impairment	500,000	6,200,000
Fair value of property, plant and equipment	3,800,000
Polybatch Color Center [Member]
Property, Plant and Equipment
Asset impairment		1,900,000	5,700,000
Fair value of property, plant and equipment		$ 2,000,000