Property, Plant and Equipment (Details) - USD ($) $ in Thousands	Aug. 31, 2017	Aug. 31, 2016
Property, plant and equipment
Property, plant and equipment, gross	$ 79,037	$ 78,151
Accumulated depreciation	(44,277)	(41,409)
Property, plant and equipment, net	34,760	36,742
Land and improvements
Property, plant and equipment
Property, plant and equipment, gross	6,478	6,561
Buildings
Property, plant and equipment
Property, plant and equipment, gross	19,447	20,364
Machinery and equipment
Property, plant and equipment
Property, plant and equipment, gross	49,211	48,374
Leasehold improvements
Property, plant and equipment
Property, plant and equipment, gross	1,049	945
Construction in progress
Property, plant and equipment
Property, plant and equipment, gross	$ 2,852	$ 1,907

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

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 360
-SubTopic 10
-Section 50
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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.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
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Amount after accumulated depreciation, depletion and amortization of physical assets used in the normal conduct of business to produce goods and services and not intended for resale. Examples include, but are not limited to, land, buildings, machinery and equipment, office equipment, and furniture and fixtures.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 210
-SubTopic 10
-Section S99
-Paragraph 1
-Subparagraph (SX 210.5-02(13))
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Reference 2: http://www.xbrl.org/2003/role/presentationRef
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