Property, Buildings and Equipment, net (Details) - USD ($) $ in Thousands	Jul. 31, 2018	Jul. 31, 2017
Property, buildings and equipment [Abstract]
Property, plant and equipment, gross	$ 20,669	$ 20,943
Accumulated depreciation and amortization	(16,799)	(16,666)
Property, buildings and equipment, net	3,870	4,277
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	7,455	7,338
Field Equipment [Member]
Property, buildings and equipment [Abstract]
Property, plant and equipment, gross	1,970	2,153
Computer Equipment [Member]
Property, buildings and equipment [Abstract]
Property, plant and equipment, gross	4,156	4,166
Computer Software [Member]
Property, buildings and equipment [Abstract]
Property, plant and equipment, gross	2,940	3,041
Office Furniture and Equipment [Member]
Property, buildings and equipment [Abstract]
Property, plant and equipment, gross	2,142	2,138
Vehicles [Member]
Property, buildings and equipment [Abstract]
Property, plant and equipment, gross	1,134	1,331
Other [Member]
Property, buildings and equipment [Abstract]
Property, plant and equipment, gross	$ 479	$ 383

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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