Annual report pursuant to Section 13 and 15(d)

Segment reporting (Details) - Schedule Of Segment Revenue By Geographical

v2.4.0.8
Segment reporting (Details) - Schedule Of Segment Revenue By Geographical (USD $)
In Thousands, unless otherwise specified
12 Months Ended
Jul. 31, 2013
Jul. 31, 2012
Jul. 31, 2011
Segment reporting (Details) - Schedule Of Segment Revenue By Geographical [Line Items]      
Sales Revenue Net $ 93,707 $ 103,083 $ 102,029
Life Sciences [Member] | UNITED STATES
     
Segment reporting (Details) - Schedule Of Segment Revenue By Geographical [Line Items]      
Sales Revenue Net 24,669 28,372 32,928
Life Sciences [Member] | Foreign Countries [Member]
     
Segment reporting (Details) - Schedule Of Segment Revenue By Geographical [Line Items]      
Sales Revenue Net 13,149 15,308 16,339
Life Sciences [Member]
     
Segment reporting (Details) - Schedule Of Segment Revenue By Geographical [Line Items]      
Sales Revenue Net 37,818 43,680 49,267
UNITED STATES
     
Segment reporting (Details) - Schedule Of Segment Revenue By Geographical [Line Items]      
Sales Revenue Net $ 80,559 $ 87,776 $ 85,691