Intangible Assets, Goodwill and Long-Lived Assets - Additional Information (Detail) (USD $) In Thousands, unless otherwise specified	12 Months Ended
	Jul. 31, 2014	Jul. 31, 2013	Jul. 31, 2012
Goodwill And Other Intangible Assets [Line Items]
Aggregate amortization expense for amortizable intangibles	$ 12,984	$ 11,037	$ 11,135
Aggregate amortization expense for amortizable intangibles for continuing operations	12,920	10,460	10,651
Goodwill impairment	$ 0	$ 0	$ 0