Consolidated Balance Sheets (Parenthetical) (USD $) In Thousands, except Share data	Jul. 31, 2011	Jul. 31, 2010
Consolidated Balance Sheets
Accounts receivable, allowance	$ 6,908	$ 6,315
Preferred stock, share par value	$ 1	$ 1
Preferred stock, shares authorized	1,000,000	1,000,000
Preferred stock, shares issued	0	0
Common stock, share par value	$ 5	$ 5
Common stock, shares authorized	120,000,000	120,000,000
Common stock, shares issued	88,643,194	88,643,194
Treasury stock, shares	13,245,864	12,222,381