Condensed Consolidated Balance Sheets (Parenthetical) (USD $) In Thousands, except Share data, unless otherwise specified	Apr. 30, 2012	Jul. 31, 2011
Condensed Consolidated Balance Sheets [Abstract]
Trade accounts receivable, allowance	$ 375	$ 351
Preferred stock, par value	$ 0.001	$ 0.001
Preferred stock, shares authorized	10,000,000	10,000,000
Preferred stock, shares issued	0	0
Preferred stock, shares outstanding	0	0
Common stock, par value	$ 0.005	$ 0.005
Common stock, shares authorized	10,000,000	10,000,000
Common stock, shares issued	3,016,758	3,003,985
Treasury stock, shares	139,580	139,580