Condensed Consolidated Balance Sheets (Parenthetical) (USD $) In Thousands, except Share data, unless otherwise specified	Jan. 31, 2013	Jul. 31, 2012
Condensed Consolidated Balance Sheets [Abstract]
Accounts receivable, allowance	$ 7,037	$ 6,418
Preferred stock, par value	$ 1	$ 1
Preferred stock, shares authorized	1,000,000	1,000,000
Preferred stock, shares issued	0	0
Common stock, par value	$ 5	$ 5
Common stock, shares authorized	240,000,000	240,000,000
Common stock, shares issued	151,643,194	151,643,194
Treasury stock, shares	4,761,074	3,980,832