Quarterly report pursuant to Section 13 or 15(d)

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

v3.19.2
Goodwill and intangible assets (Details) - Schedule of intangible assets - USD ($)
$ in Thousands
Apr. 30, 2019
Jul. 31, 2018
Goodwill and intangible assets (Details) - Schedule of intangible assets [Line Items]    
Finite-lived intangible assets, Gross $ 27,237 $ 27,347
Finite-lived intangible assets, Accumulated Amortization (26,109) (25,461)
Finite-lived intangible assets, Net 1,128 1,886
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 (10,992) (10,980)
Finite-lived intangible assets, Net 35 47
Customer Relationships [Member]    
Goodwill and intangible assets (Details) - Schedule of intangible assets [Line Items]    
Finite-lived intangible assets, Gross 11,745 11,836
Finite-lived intangible assets, Accumulated Amortization (10,652) (9,997)
Finite-lived intangible assets, Net 1,093 1,839
Website And Acquired Content [Member]    
Goodwill and intangible assets (Details) - Schedule of intangible assets [Line Items]    
Finite-lived intangible assets, Gross 1,008 1,008
Finite-lived intangible assets, Accumulated Amortization (1,008) (1,008)
Licensed Technology And Other [Member]    
Goodwill and intangible assets (Details) - Schedule of intangible assets [Line Items]    
Finite-lived intangible assets, Gross 483 483
Finite-lived intangible assets, Accumulated Amortization (483) (483)
Trademarks [Member]    
Goodwill and intangible assets (Details) - Schedule of intangible assets [Line Items]    
Finite-lived intangible assets, Gross 2,974 2,993
Finite-lived intangible assets, Accumulated Amortization $ (2,974) $ (2,993)