Summary of Significant Accounting Policies (Details) (USD $)	12 Months Ended
Jul. 31, 2013 item	Jul. 31, 2012	Jul. 31, 2011
Revenue recognition - reductions
Number of customers all products shipped FOB destination	1
Period for returning sterility assurance products	90 days
Volume rebates	$ 4,277,000	$ 3,836,000	$ 3,234,000

The aggregate selling price reductions recognized during an accounting period including, but not limited to, the sale of defective or nonconforming goods, a strategy to increase sales (generally over the short-term), move slow-moving items, develop distribution channels, or reward valuable customers. Allowances are a deduction from gross revenue in arriving at net revenue.

Reference 1: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 225

-SubTopic 10

-Section S99

-Paragraph 2

-Subparagraph (SX 210.5-03.1(a))

-URI http://asc.fasb.org/extlink&oid=6880815&loc=d3e20235-122688

Reference 2: http://www.xbrl.org/2003/role/presentationRef

-Publisher SEC

-Name Regulation S-X (SX)

-Number 210

-Section 03

-Paragraph 1

-Article 5

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Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	duration