Annual report pursuant to Section 13 and 15(d)

Summary of significant accounting policies (Details) - Net accounts receivable by segment

v3.5.0.2
Summary of significant accounting policies (Details) - Net accounts receivable by segment - USD ($)
$ in Thousands
Jul. 31, 2016
Jul. 31, 2015
Clinical Labs (by billing category)    
Accounts Receivable Net Current $ 14,592 $ 12,109
Clinical Labs [Member]    
Clinical Labs (by billing category)    
Accounts Receivable Net Current $ 10,364 $ 8,194
Accounts Receivable Net Current Percentage 100.00% 100.00%
Life Sciences [Member]    
Clinical Labs (by billing category)    
Accounts Receivable Net Current $ 4,228 $ 3,915
Third-Party Payor [Member] | Clinical Labs [Member]    
Clinical Labs (by billing category)    
Accounts Receivable Net Current $ 6,868 $ 3,595
Accounts Receivable Net Current Percentage 67.00% 44.00%
Self-Pay [Member] | Clinical Labs [Member]    
Clinical Labs (by billing category)    
Accounts Receivable Net Current $ 1,676 $ 3,213
Accounts Receivable Net Current Percentage 16.00% 39.00%
Medicare [Member] | Clinical Labs [Member]    
Clinical Labs (by billing category)    
Accounts Receivable Net Current $ 1,486 $ 1,081
Accounts Receivable Net Current Percentage 14.00% 13.00%
Health Maintenance Organizations [Member] | Clinical Labs [Member]    
Clinical Labs (by billing category)    
Accounts Receivable Net Current $ 334 $ 305
Accounts Receivable Net Current Percentage 3.00% 4.00%