Segment Information - Net Income Reconciliation (Detail) (USD $) In Thousands, unless otherwise specified	3 Months Ended			9 Months Ended
	Apr. 30, 2013	Jan. 31, 2013	Apr. 30, 2012	Apr. 30, 2013	Apr. 30, 2012
Segment Reporting, Reconciling Item for Operating Profit (Loss) from Segment to Consolidated [Line Items]
Operating income, corporate eliminations	$ (1,282)		$ (388)	$ (5,049)	$ (6,010)
Total profit from reportable segments	71,420		70,827	205,540	215,714
Unallocated amounts:
Administrative costs	(30,642)		(25,506)	(94,042)	(82,636)
Restructuring charges	(8,540)	(1,947)	(1,977)	(10,487)	(1,977)
Investment and other income	1,131		1,108	2,427	1,719
Interest Expense	(4,185)		(4,735)	(12,755)	(14,715)
Earnings from continuing operations before income taxes	27,902		39,329	85,634	112,095
Income Tax Expense (Benefit), Continuing Operations	(6,064)		(11,290)	(47,965)	(27,767)
Income (Loss) from Continuing Operations Attributable to Parent	21,838		28,039	37,669	84,328
Income (Loss) from Discontinued Operations, Net of Tax, Attributable to Parent	(17,605)		(387)	(14,933)	(113,898)
Net (loss) income	$ 4,233		$ 27,652	$ 22,736	$ (29,570)