Annual report pursuant to Section 13 and 15(d)

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

v3.10.0.1
Goodwill and intangible assets (Details) - Schedule of intangible assets - USD ($)
$ in Thousands
Jul. 31, 2018
Jul. 31, 2017
Goodwill and intangible assets (Details) - Schedule of intangible assets [Line Items]    
Finite-lived intangible assets, Gross $ 27,347 $ 27,436
Finite-lived intangible assets, Accumulated Amortization (25,461) (24,541)
Finite-lived intangible assets, Net 1,886 2,895
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 (10,980) (10,951)
Finite-lived intangible assets, Net 47 76
Customer Relationships [Member]    
Goodwill and intangible assets (Details) - Schedule of intangible assets [Line Items]    
Finite-lived intangible assets, Gross 11,836 11,881
Finite-lived intangible assets, Accumulated Amortization (9,997) (9,083)
Finite-lived intangible assets, Net 1,839 2,798
Website And Acquired Content [Member]    
Goodwill and intangible assets (Details) - Schedule of intangible assets [Line Items]    
Finite-lived intangible assets, Gross 1,008 1,011
Finite-lived intangible assets, Accumulated Amortization (1,008) (1,011)
Licensed Technology And Other [Member]    
Goodwill and intangible assets (Details) - Schedule of intangible assets [Line Items]    
Finite-lived intangible assets, Gross 483 484
Finite-lived intangible assets, Accumulated Amortization (483) (463)
Finite-lived intangible assets, Net   21
Trademarks [Member]    
Goodwill and intangible assets (Details) - Schedule of intangible assets [Line Items]    
Finite-lived intangible assets, Gross 2,993 3,033
Finite-lived intangible assets, Accumulated Amortization $ (2,993) $ (3,033)