Schedule of Components of Provision (Benefit) for Income Taxes from Continuing Operations (Detail) (USD $) In Thousands, unless otherwise specified	12 Months Ended
Jul. 31, 2014	Jul. 31, 2013	Jul. 31, 2012
Income Taxes Provision Benefit Summary Of Income Taxes [Line Items]
Federal	$ 83,374	$ 74,610	$ 52,665
State and local	(1,383)	4,187	4,250
Total current expense (benefit)	81,991	78,797	56,915
Federal	(3,805)	(7,712)	(2,888)
State and local	(883)	(789)	(74)
Total deferred expense (benefit)	(4,688)	(8,501)	(2,962)
Total income tax expense	$ 77,303	$ 70,296	$ 53,953

Amount of current federal tax expense (benefit) pertaining to income (loss) from continuing operations.

Amount of current income tax expense (benefit) pertaining to taxable income (loss) from continuing operations.

Amount of current state and local tax expense (benefit) pertaining to income (loss) from continuing operations.

Amount of deferred federal income tax expense (benefit) pertaining to income (loss) from continuing operations.

Amount of deferred income tax expense (benefit) pertaining to income (loss) from continuing operations.

Amount of deferred state and local tax expense (benefit) pertaining to income (loss) from continuing operations.