Segment Information (Details 1) (USD $) In Thousands, unless otherwise specified	3 Months Ended		6 Months Ended
	Jan. 31, 2012	Jan. 31, 2011	Jan. 31, 2012	Jan. 31, 2011
Net income reconciliation
Total profit from reportable segments	$ 70,093	$ 71,704	$ 152,926	$ 151,953
Corporate and eliminations	(2,359)	(5,088)	(5,622)	(8,525)
Unallocated amounts:
Administrative costs	(29,244)	(27,402)	(59,724)	(58,970)
Restructuring charges		(2,134)		(5,775)
Impairment charge	(115,688)		(115,688)
Investment and other income (expense)	812	1,174	610	1,464
Interest expense	(4,933)	(5,850)	(9,980)	(11,537)
(Loss) Income before income taxes	(81,319)	32,404	(37,478)	68,610
Income taxes	(8,635)	(8,205)	(19,744)	(18,130)
Net (loss) income	(89,954)	24,199	(57,222)	50,480
Segment Reporting (Textual) [Abstract]
Goodwill impairment charge	$ 115,688		$ 115,688