Condensed Consolidated Balance Sheets (Parenthetical) (USD $)	Oct. 31, 2013	Jul. 31, 2013
Stockholders’ equity:
Preferred stock, par value (in dollars per share)	$ 0.10	$ 0.10
Preferred stock, shares authorized (in shares)	2,000,000	2,000,000
Preferred stock, shares issued (in shares)	0	0
Common stock, par value (in dollars per share)	$ 0.10	$ 0.10
Common stock, shares authorized (in shares)	100,000,000	100,000,000
Common stock, shares issued (in shares)	29,084,683	29,066,792
Treasury stock, shares (in shares)	12,733,254	12,608,501