Fair Value Measurements - Additional Information (Detail) - USD ($)	3 Months Ended
	Oct. 29, 2016	Oct. 31, 2015	Jul. 30, 2016
Quoted Prices in Active Markets for Identical Assets and Liabilities (Level 1) | Money market funds
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Assets Fair Value	$ 96,600,000	$ 0	$ 110,300,000
Significant Other Observable Inputs (Level 2) | Forward foreign exchange contracts
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Assets Fair Value	69,000
Liabilities Fair Value		27,000	$ 123,000
Under-Performing Stores
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Property and equipment impairment charges	$ 500,000	$ 200,000