Annual report pursuant to Section 13 and 15(d)

Goodwill and intangible assets (Details) - Schedule of intangible assets

v3.7.0.1
Goodwill and intangible assets (Details) - Schedule of intangible assets - USD ($)
$ in Thousands
Jul. 31, 2017
Jul. 31, 2016
Goodwill and intangible assets (Details) - Schedule of intangible assets [Line Items]    
Finite-lived intangible assets, Gross $ 27,436 $ 27,650
Finite-lived intangible assets, Accumulated Amortization (24,541) (23,228)
Finite-lived intangible assets, Net 2,895 4,422
Patents [Member]    
Goodwill and intangible assets (Details) - Schedule of intangible assets [Line Items]    
Finite-lived intangible assets, Gross 11,027 11,027
Finite-lived intangible assets, Accumulated Amortization (10,951) (10,905)
Finite-lived intangible assets, Net 76 122
Customer Relationships [Member]    
Goodwill and intangible assets (Details) - Schedule of intangible assets [Line Items]    
Finite-lived intangible assets, Gross 11,881 12,122
Finite-lived intangible assets, Accumulated Amortization (9,083) (8,331)
Finite-lived intangible assets, Net 2,798 3,791
Website And Acquired Content [Member]    
Goodwill and intangible assets (Details) - Schedule of intangible assets [Line Items]    
Finite-lived intangible assets, Gross 1,011 1,011
Finite-lived intangible assets, Accumulated Amortization (1,011) (1,011)
Licensed Technology And Other [Member]    
Goodwill and intangible assets (Details) - Schedule of intangible assets [Line Items]    
Finite-lived intangible assets, Gross 484 485
Finite-lived intangible assets, Accumulated Amortization (463) (437)
Finite-lived intangible assets, Net 21 48
Trademarks [Member]    
Goodwill and intangible assets (Details) - Schedule of intangible assets [Line Items]    
Finite-lived intangible assets, Gross 3,033 3,005
Finite-lived intangible assets, Accumulated Amortization $ (3,033) (2,544)
Finite-lived intangible assets, Net   $ 461