Property, Plant and Equipment (Property, Plant and Equipment) (Details) (USD $) In Thousands, unless otherwise specified	Nov. 30, 2013	Aug. 31, 2013
Property, Plant and Equipment [Line Items]
Total property, plant and equipment, gross	$ 152,373	$ 151,322
Less accumulated depreciation	(131,316)	(131,056)
Total property, plant and equipment, net	21,057	20,266
Land [Member]
Property, Plant and Equipment [Line Items]
Total property, plant and equipment, gross	757	757
Buildings and building improvements [Member]
Property, Plant and Equipment [Line Items]
Total property, plant and equipment, gross	50,570	50,297
Machinery and equipment [Member]
Property, Plant and Equipment [Line Items]
Total property, plant and equipment, gross	92,014	91,224
Transportation [Member]
Property, Plant and Equipment [Line Items]
Total property, plant and equipment, gross	$ 9,032	$ 9,044