Annual report pursuant to Section 13 and 15(d)

Summary of significant accounting policies (Details) - Amount of expense related to share-based payment arrangements

v3.3.0.814
Summary of significant accounting policies (Details) - Amount of expense related to share-based payment arrangements - USD ($)
$ in Thousands
12 Months Ended
Jul. 31, 2015
Jul. 31, 2014
Jul. 31, 2013
Share-based Compensation Arrangement by Share-based Payment Award, Compensation Cost [Line Items]      
Share Based Compensation $ 429 $ 594 $ 545
Cost of Clinical Laboratory Services [Member]      
Share-based Compensation Arrangement by Share-based Payment Award, Compensation Cost [Line Items]      
Share Based Compensation 5 9 10
Research and Development Expense [Member]      
Share-based Compensation Arrangement by Share-based Payment Award, Compensation Cost [Line Items]      
Share Based Compensation 2 1 2
Selling, General and Administrative Expenses [Member]      
Share-based Compensation Arrangement by Share-based Payment Award, Compensation Cost [Line Items]      
Share Based Compensation $ 422 $ 584 $ 533