Enterprise-wide Sales Information (Details) - USD ($) $ in Thousands		12 Months Ended
		Jul. 31, 2015	Jul. 31, 2014	Jul. 31, 2013
Revenue from External Customer [Line Items]
Net sales		$ 75,019	$ 64,769	$ 62,796
Revenues from External Customers [Line Items]
Net sales		75,019	64,769	62,796
Alcon [Member]
Revenues from External Customers [Line Items]
Recognition of deferred revenue		1,300	1,300	1,300
Ophthalmic [Member]
Revenue from External Customer [Line Items]
Net sales	[1]	41,976	37,433	36,348
Neurosurgery [Member]
Revenue from External Customer [Line Items]
Net sales	[2]	31,694	26,844	25,834
Other [Member]
Revenue from External Customer [Line Items]
Net sales	[3]	1,349	492	614
Ophthalmic [Member]
Revenue from External Customer [Line Items]
Net sales	[4]	33,509	35,242	35,446
OEM [Member]
Revenue from External Customer [Line Items]
Net sales	[5]	40,678	28,671	26,469
Other [Member]
Revenue from External Customer [Line Items]
Net sales	[6]	832	856	881
Domestic [Member]
Revenues from External Customers [Line Items]
Net sales		52,530	47,794	46,489
International [Member]
Revenues from External Customers [Line Items]
Net sales		$ 22,489	$ 16,975	$ 16,307

[1] Net sales from Ophthalmic represent all sales of ophthalmic devices from direct sales representatives, distribution partners and OEMs. Recognition of deferred revenue of $1.3 million from Alcon is included in this category for the fiscal years ended 2015, 2014 and 2013, respectively.

[2] Net sales from Neurosurgery 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 certain neurosurgery disposables sold through distribution. Many of the products that the Company sells to its neurosurgery OEM customers are shipped to their non-U.S. customers in various countries around the world, but are included in the Company's domestic revenues.

[3] Other net sales represent all sales of aesthetic devices and other miscellaneous revenues.

[4] Net sales from Ophthalmic represent sales of ophthalmic devices from direct sales representatives and distribution partners.

[5] 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. Recognition of deferred revenues of $1.3 million from Alcon is included in this category for the fiscal years ended 2015, 2014 and 2013, respectively. Many of the products that the Company sells to its neurosurgery OEM customers are shipped to their non-U.S. customers in various countries around the world, but are included in the Company's domestic revenues.

[6] Other net sales represent direct neurosurgery revenues and other miscellaneous revenues.