Enterprise-wide Sales Information (Details) (USD $)	3 Months Ended
	Oct. 31, 2013		Oct. 31, 2012
Revenue from External Customer [Line Items]
Net sales	$ 15,530,000		$ 14,620,000
Revenues from External Customers [Line Items]
Net sales	15,530,000		14,620,000
Alcon [Member]
Revenues from External Customers [Line Items]
Recognition of deferred revenue	322,000		322,000
Domestic [Member]
Revenues from External Customers [Line Items]
Net sales	11,869,000		10,832,000
International [Member]
Revenues from External Customers [Line Items]
Net sales	3,661,000		3,788,000
Ophthalmic [Member]
Revenue from External Customer [Line Items]
Net sales	8,498,000		8,662,000
OEM [Member]
Revenue from External Customer [Line Items]
Net sales	6,848,000	[1]	5,749,000	[1]
Other [Member]
Revenue from External Customer [Line Items]
Net sales	$ 184,000	[2]	$ 209,000	[2]

[1] Net sales from OEM represent sales of electrosurgery generators, disposable bipolar forceps and related accessories and royalties from Codman, multi-channel generators, disposable ultrasonic tips and related accessories to Stryker and sales of certain disposable products to Mobius Therapeutics LLC (“Mobius”). In addition, deferred revenues of $322,000 from Alcon are included in this category for the three months ended October 31, 2013 and 2012, respectively.

[2] Net sales from Other represent direct neurosurgery revenues and other miscellaneous revenues.