Income Taxes - Additional Information (Detail) - USD ($)	12 Months Ended
	Jul. 31, 2015	Jul. 31, 2014	Jul. 31, 2013
Income Tax [Line Items]
Tax credit carry forward	$ 110,000	$ 790,000
Unrecognized tax benefits that, if recognized, would affect the company's income tax rate	8,764,000	13,679,000	$ 21,765,000
Tax positions related to prior years: Reductions	7,695,000	9,281,000	113,000
Accrued interest and penalties	1,895,000	5,200,000	11,671,000
Total amount of interest and penalties expense (benefit) recognized	(2,552,000)	(3,418,000)	$ (932,000)
Expected decrease in unrecognized tax benefits due to resolution of uncertain tax positions	3,520,000
Expected decrease in interest due to resolution of uncertain tax positions	920,000
Expected decrease in penalties due to resolution of uncertain tax positions	17,000
Discontinued Operations
Income Tax [Line Items]
Tax positions related to prior years: Reductions		$ 1,378,000
State and Local Jurisdiction
Income Tax [Line Items]
Tax credit carry forward	167,000
Gross state tax Net Operating Loss carry forwards	57,400,000
Deferred tax asset, Net Operating Loss carry forwards	$ 1,595,000
State and Local Jurisdiction | Earliest Tax Year
Income Tax [Line Items]
Tax credit carry forward expiration year	2022
Gross state tax Net Operating Loss carry forwards, expiration year	2016
State and Local Jurisdiction | Latest Tax Year
Income Tax [Line Items]
Tax credit carry forward expiration year	2025
Gross state tax Net Operating Loss carry forwards, expiration year	2035
IRS
Income Tax [Line Items]
Tax audit assessments	$ 0