Quarterly report pursuant to Section 13 or 15(d)

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

v3.20.1
Goodwill and intangible assets (Details) - Schedule of Intangible Assets - USD ($)
$ in Thousands
Apr. 30, 2020
Jul. 31, 2019
Goodwill and intangible assets (Details) - Schedule of Intangible Assets [Line Items]    
Finite-lived intangible assets, Gross $ 27,285 $ 27,238
Finite-lived intangible assets, Accumulated Amortization (26,697) (26,206)
Finite-lived intangible assets, Net 588 1,032
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 (11,010) (10,996)
Finite-lived intangible assets, Net 17 31
Customer Relationships [Member]    
Goodwill and intangible assets (Details) - Schedule of Intangible Assets [Line Items]    
Finite-lived intangible assets, Gross 11,791 11,746
Finite-lived intangible assets, Accumulated Amortization (11,220) (10,745)
Finite-lived intangible assets, Net 571 1,001
Website And Acquired Content [Member]    
Goodwill and intangible assets (Details) - Schedule of Intangible Assets [Line Items]    
Finite-lived intangible assets, Gross 1,009 1,008
Finite-lived intangible assets, Accumulated Amortization (1,009) (1,008)
Finite-lived intangible assets, Net
Licensed Technology And Other [Member]    
Goodwill and intangible assets (Details) - Schedule of Intangible Assets [Line Items]    
Finite-lived intangible assets, Gross 475 483
Finite-lived intangible assets, Accumulated Amortization (475) (483)
Finite-lived intangible assets, Net
Trademarks [Member]    
Goodwill and intangible assets (Details) - Schedule of Intangible Assets [Line Items]    
Finite-lived intangible assets, Gross 2,983 2,974
Finite-lived intangible assets, Accumulated Amortization (2,983) (2,974)
Finite-lived intangible assets, Net