Consolidated Balance Sheets (Parenthetical) - USD ($) $ in Thousands	Apr. 30, 2017	Jul. 31, 2016
ASSETS
Trade receivables, allowance for doubtful accounts	$ 225	$ 211
SHAREHOLDERS' EQUITY
Common stock, par value	$ 0.001	$ 0.001
Common stock, shares authorized	25,000,000	25,000,000
Common stock, shares issued	17,421,719	17,310,763
Common stock, shares outstanding	17,421,719	17,310,763
Cumulative Preferred Stock [Member]
SHAREHOLDERS' EQUITY
Preferred stock, par value	$ 0.001	$ 0.001
Preferred stock, shares authorized	1,000,000	1,000,000
Preferred stock, shares issued	0	0
Preferred stock, shares outstanding	0	0
Junior Preferred Stock [Member]
SHAREHOLDERS' EQUITY
Preferred stock, par value	$ 0.001	$ 0.001
Preferred stock, shares authorized	100,000	100,000
Preferred stock, shares issued	0	0
Preferred stock, shares outstanding	0	0