Property, Plant and Equipment (Details) - USD ($) $ in Thousands	Aug. 31, 2019	Aug. 31, 2018
Property, plant and equipment
Property, plant and equipment, gross	$ 79,056	$ 82,057
Accumulated depreciation	(49,730)	(49,212)
Property, plant and equipment, net	29,326	32,845
Land and improvements
Property, plant and equipment
Property, plant and equipment, gross	6,079	6,499
Buildings
Property, plant and equipment
Property, plant and equipment, gross	17,900	19,484
Machinery and equipment
Property, plant and equipment
Property, plant and equipment, gross	51,934	52,259
Leasehold improvements
Property, plant and equipment
Property, plant and equipment, gross	1,828	1,612
Construction in progress
Property, plant and equipment
Property, plant and equipment, gross	$ 1,315	$ 2,203

Amount of accumulated depreciation, depletion and amortization for physical assets used in the normal conduct of business to produce goods and services.

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Amount before accumulated depreciation, depletion and amortization of physical assets used in the normal conduct of business and not intended for resale. Examples include, but are not limited to, land, buildings, machinery and equipment, office equipment, and furniture and fixtures.

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