Quarterly Financial Data (Unaudited) (Details) (USD $)	3 Months Ended									12 Months Ended
	Jul. 31, 2012	Apr. 30, 2012		Jan. 31, 2012	Oct. 31, 2011	Jul. 31, 2011	Apr. 30, 2011	Jan. 31, 2011	Oct. 31, 2010	Jul. 31, 2012	Jul. 31, 2011	Jul. 31, 2010
Quarterly Financial Data (Unaudited) [Abstract]
Net Sales	$ 16,861,000	$ 14,568,000		$ 15,080,000	$ 13,505,000	$ 15,652,000	$ 14,670,000	$ 13,278,000	$ 12,057,000
Gross Profit	9,809,000	7,822,000	[1]	8,972,000	7,916,000	9,428,000	8,596,000	7,730,000	7,027,000	34,519,000	32,781,000	29,960,000
Operating Income	2,946,000	1,405,000		2,618,000	1,512,000	2,966,000	2,516,000	1,834,000	1,033,000	8,481,000	8,349,000	6,091,000
Loss on sale of product line						0	0	(99,000)	0	0	(99,000)	817,000
Income from continuing operations	1,942,000	1,006,000		1,867,000	1,153,000	2,041,000	1,676,000	1,316,000	636,000	5,968,000	5,669,000	5,767,000
Loss from discontinued operations	0	0		0	382,000	4,000	33,000	(4,000)	3,000	(382,000)	(36,000)	(34,000)
Net Income	1,942,000	1,006,000		1,867,000	771,000	2,037,000	1,643,000	1,320,000	633,000	5,586,000	5,633,000	5,733,000
Earnings per share - basic
Income from continuing operations (in dollars per share)	$ 0.08	$ 0.04		$ 0.07	$ 0.05	$ 0.08	$ 0.07	$ 0.05	$ 0.03	$ 0.24	$ 0.23	$ 0.23
Loss from discontinued operations (in dollars per share)	$ 0.00	$ 0.00		$ 0.00	$ (0.02)	$ 0.00	$ 0.00	$ 0.00	$ 0.00	$ (0.02)	$ 0.00	$ 0.00
Net income (in dollars per share)	$ 0.08	$ 0.04		$ 0.07	$ 0.03	$ 0.08	$ 0.07	$ 0.05	$ 0.03	$ 0.22	$ 0.23	$ 0.23
Earnings per share - diluted
Income from continuing operations (in dollars per share)	$ 0.08	$ 0.04		$ 0.07	$ 0.05	$ 0.08	$ 0.07	$ 0.05	$ 0.03	$ 0.24	$ 0.23	$ 0.23
Loss from discontinued operations (in dollars per share)	$ 0.00	$ 0.00		$ 0.00	$ (0.02)	$ 0.00	$ 0.00	$ 0.00	$ 0.00	$ (0.02)	$ 0.00	$ 0.00
Net income (in dollars per share)	$ 0.08	$ 0.04		$ 0.07	$ 0.03	$ 0.08	$ 0.07	$ 0.05	$ 0.03	$ 0.22	$ 0.23	$ 0.23
Basic weighted average common shares outstanding (in share)	25,165,493	25,184,447		25,085,296	24,971,034	24,970,271	24,945,707	24,937,463	24,782,913	25,100,064	24,901,832	24,618,403
Diluted weighted average common shares outstanding (in share)	25,293,168	25,363,620		25,280,449	25,136,727	25,137,786	25,108,582	25,074,230	24,862,420	25,256,584	25,035,095	24,672,605
Inventory Write-down	$ 367,000
Earnings per share (in dollars per share)	$ 0.01

[1] In the third quarter of fiscal 2012, the Company recorded an inventory write-down of approximately $367,000, or approximately $0.01 earnings per share, net of tax.