Annual report pursuant to Section 13 and 15(d)

Summary of Significant Accounting Policies (Details)

v3.21.2
Summary of Significant Accounting Policies (Details)
$ in Thousands
 12 Months Ended
Jul. 31, 2021
USD ($)
shares
Jul. 31, 2020
USD ($)
shares
Jul. 31, 2019
USD ($)
shares
Aug. 01, 2019
USD ($)
Summary of Significant Accounting Policies (Details) [Line Items]        
Number of operating segments 3      
Fair value of investments   $ 29,978    
Fair value investments cost basis   $ 30,061    
Unrealized Loss on Securities $ 83      
Contractual adjustment percentages 83.00% 88.00% 88.00%  
Advertising expense $ 400 $ 437 $ 374  
Weighted average stock options (in Shares) | shares 134,000   125,000  
Share-based compensation expense $ 907 923 $ 939  
Employee benefits and share based compensation 10      
Share-based payment arrangement, nonvested award, option, cost not yet recognized, amount $ 755      
Share-based payment arrangement, nonvested award, cost not yet recognized, period for recognition 15 months      
Right-of-use assets $ 17,020 19,916   $ 24,400
Operating lease liabilities 14,558 16,679   25,100
Deferred rent credit, current       $ 700
Foreign bank [Member]        
Summary of Significant Accounting Policies (Details) [Line Items]        
Cash and cash equivalents $ 909 $ 909    
In the money stock options [Member] | Unvested Restricted Stock [Member]        
Summary of Significant Accounting Policies (Details) [Line Items]        
Antidilutive securities excluded from computation of earnings per share, amount (in Shares) | shares   40,000    
Out of the Money [Member]        
Summary of Significant Accounting Policies (Details) [Line Items]        
Antidilutive securities excluded from computation of earnings per share, amount (in Shares) | shares 1,465,000 1,904,000 1,324,000  
Patents [Member]        
Summary of Significant Accounting Policies (Details) [Line Items]        
Finite-lived intangible asset, useful life 10 years      
Minimum [Member]        
Summary of Significant Accounting Policies (Details) [Line Items]        
Finite-lived intangible asset, useful life 4 years      
Minimum [Member] | Building and Building Improvements [Member]        
Summary of Significant Accounting Policies (Details) [Line Items]        
Property, plant and equipment, useful life 15 years      
Minimum [Member] | Machinery and Equipment [Member]        
Summary of Significant Accounting Policies (Details) [Line Items]        
Property, plant and equipment, useful life 3 years      
Maximum [Member]        
Summary of Significant Accounting Policies (Details) [Line Items]        
Finite-lived intangible asset, useful life 15 years      
Maximum [Member] | Building and Building Improvements [Member]        
Summary of Significant Accounting Policies (Details) [Line Items]        
Property, plant and equipment, useful life 30 years      
Maximum [Member] | Machinery and Equipment [Member]        
Summary of Significant Accounting Policies (Details) [Line Items]        
Property, plant and equipment, useful life 10 years      
Clinical Revenue [Member]        
Summary of Significant Accounting Policies (Details) [Line Items]        
Concentration risk percentage 48.00% 8.00%    
Clinical Services [Member] | Revenue Benchmark [Member] | Third Party Payer [Member]        
Summary of Significant Accounting Policies (Details) [Line Items]        
Clinical Services net revenue 35.00%      
Clinical Services net accounts receivable percentage 27.00%      
Clinical Services [Member] | Revenue Benchmark [Member] | Health Maintenance Organization [Member]        
Summary of Significant Accounting Policies (Details) [Line Items]        
Clinical Services net revenue   24.00% 36.00%  
Clinical Services net accounts receivable percentage   16.00%    
Clinical Laboratory Services [Member]        
Summary of Significant Accounting Policies (Details) [Line Items]        
Receivable percentage 59.00% 68.00%