Consolidated Balance Sheets (Parenthetical) (USD $) In Thousands, except Share data	Jul. 31, 2011	Jul. 31, 2010
Consolidated Balance Sheets
Trade receivables, allowances	$ 3,423	$ 2,259
Inventories, reserves	$ 1,552	$ 1,452
Preferred stock, par value	$ 0.01	$ 0.01
Preferred stock, shares authorized	25,000,000	25,000,000
Preferred stock, shares issued	0	0
Preferred stock, shares outstanding	0	0
Common stock, par value	$ 0.01	$ 0.01
Common stock, shares authorized	100,000,000	100,000,000
Common stock, shares issued	40,334,973	40,173,891
Treasury stock, shares	4,264,804	4,264,804