Property, Buildings and Equipment, net (Details) - USD ($) $ in Thousands	Jul. 31, 2019	Jul. 31, 2018
Property, buildings and equipment [Abstract]
Property, plant and equipment, gross	$ 20,319	$ 20,669
Accumulated depreciation and amortization	(17,066)	(16,799)
Property, buildings and equipment, net	3,253	3,870
Land and Land Improvements [Member]
Property, buildings and equipment [Abstract]
Property, plant and equipment, gross	393	393
Building and Building Improvements [Member]
Property, buildings and equipment [Abstract]
Property, plant and equipment, gross	7,471	7,455
Field Equipment [Member]
Property, buildings and equipment [Abstract]
Property, plant and equipment, gross	1,949	1,970
Computer Equipment [Member]
Property, buildings and equipment [Abstract]
Property, plant and equipment, gross	4,015	4,156
Computer Software [Member]
Property, buildings and equipment [Abstract]
Property, plant and equipment, gross	2,981	2,940
Office Furniture and Equipment [Member]
Property, buildings and equipment [Abstract]
Property, plant and equipment, gross	1,964	2,142
Vehicles [Member]
Property, buildings and equipment [Abstract]
Property, plant and equipment, gross	884	1,134
Other [Member]
Property, buildings and equipment [Abstract]
Property, plant and equipment, gross	$ 662	$ 479

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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-Publisher FASB
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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

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+ References

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