Annual report pursuant to Section 13 and 15(d)

Segment reporting (Details) - Schedule of segment revenue by geographical

v3.7.0.1
Segment reporting (Details) - Schedule of segment revenue by geographical - USD ($)
$ in Thousands
 12 Months Ended
Jul. 31, 2017
Jul. 31, 2016
Jul. 31, 2015
Segment reporting (Details) - Schedule of segment revenue by geographical [Line Items]      
Sales Revenue Net $ 107,804 $ 102,773 $ 97,599
UNITED STATES      
Segment reporting (Details) - Schedule of segment revenue by geographical [Line Items]      
Sales Revenue Net 99,469 94,016 87,875
Life Sciences [Member]      
Segment reporting (Details) - Schedule of segment revenue by geographical [Line Items]      
Sales Revenue Net 30,397 31,858 34,185
Life Sciences [Member] | UNITED STATES      
Segment reporting (Details) - Schedule of segment revenue by geographical [Line Items]      
Sales Revenue Net 22,062 23,102 24,461
Life Sciences [Member] | Foreign Countries [Member]      
Segment reporting (Details) - Schedule of segment revenue by geographical [Line Items]      
Sales Revenue Net $ 8,335 $ 8,756 $ 9,724