Quarterly report pursuant to Section 13 or 15(d)

Revenue Recognition (Details)

v3.19.2
Revenue Recognition (Details) - USD ($)
3 Months Ended 9 Months Ended
Apr. 30, 2019
Apr. 30, 2018
Apr. 30, 2019
Apr. 30, 2018
Third Party Payer And Health Maintenance Organizations [Member] | Minimum [Member]        
Revenue Recognition (Details) [Line Items]        
Billing Information Filing Deadline Period     60 days  
Third Party Payer And Health Maintenance Organizations [Member] | Maximum [Member]        
Revenue Recognition (Details) [Line Items]        
Billing Information Filing Deadline Period     90 days  
Government Payer Medicare [Member]        
Revenue Recognition (Details) [Line Items]        
Billing Information Filing Deadline Period     60 days  
Patient self-pay [Member]        
Revenue Recognition (Details) [Line Items]        
Billing Period     210 days  
Receivable Collection Period     180 days  
Products Revenue And Royalty Income [Member]        
Revenue Recognition (Details) [Line Items]        
Claim Period For Return Of Goods     30 days  
Royalty Income, Nonoperating (in Dollars) $ 0 $ 78,000 $ 0 $ 639,000
Products Revenue And Royalty Income [Member] | Minimum [Member]        
Revenue Recognition (Details) [Line Items]        
Receivable Collection Period     30 days  
Products Revenue And Royalty Income [Member] | Maximum [Member]        
Revenue Recognition (Details) [Line Items]        
Receivable Collection Period     90 days  
Clinical Services [Member] | Revenue Benchmark [Member]        
Revenue Recognition (Details) [Line Items]        
Concentration Risk, Percentage     63.00% 72.00%
Clinical Services [Member] | Revenue Benchmark [Member] | Third Party Payer And Health Maintenance Organizations [Member]        
Revenue Recognition (Details) [Line Items]        
Concentration Risk, Percentage 33.00% 40.00% 39.00% 39.00%