Segment Information - Net Income Reconciliation (Detail) (USD $) In Thousands, unless otherwise specified	3 Months Ended
	Oct. 31, 2013	Oct. 31, 2012
Disclosure Segment Information Net Income Reconciliation [Abstract]
Total profit from reportable segments	$ 68,484	$ 71,802
Unallocated amounts:
Administrative costs	(32,813)	(29,174)
Restructuring charges	(6,840)	0
Investment and other income	762	397
Interest Expense	(3,721)	(4,163)
Earnings from continuing operations before income taxes	25,872	38,862
Income Tax Expense (Benefit), Continuing Operations	(8,449)	(13,077)
Income (Loss) from Continuing Operations Attributable to Parent	17,423	25,785
Income (Loss) from Discontinued Operations, Net of Tax, Attributable to Parent	6,505	1,403
Net (loss) income	$ 23,928	$ 27,188