Segment Reporting (Details) - Reportable Geographical Components [Member] - USD ($) $ in Thousands		3 Months Ended
		Oct. 29, 2016	Oct. 31, 2015	Jul. 31, 2016
United States [Member]
Revenues from External Customers and Long-Lived Assets [Line Items]
Revenue		$ 20,346	$ 24,002
Long-Lived Assets		3,450		$ 4,916
South America [Member]
Revenues from External Customers and Long-Lived Assets [Line Items]
Revenue	[1]	5,259	6,060
Long-Lived Assets		1,215		$ 1,178
Peru [Member]
Revenues from External Customers and Long-Lived Assets [Line Items]
Revenue		1,100	3,000
Brazil [Member]
Revenues from External Customers and Long-Lived Assets [Line Items]
Revenue		2,200	1,100
Chile [Member]
Revenues from External Customers and Long-Lived Assets [Line Items]
Revenue		$ 2,000	$ 1,800

[1] Significant South American revenues included revenues in Peru ($1.1 million and $3.0 million for the three months ended October 29, 2016 and October 31, 2015, respectively), Brazil ($2.2 million and $1.1 million for the three months ended October 29, 2016 and October 31, 2015, respectively) and Chile ($2.0 million and $1.8 million for the three months ended October 29, 2016 and October 31, 2015, respectively).