Other Current and Long-Term Liabilities - Additional Information (Detail) - USD ($) $ in Thousands	6 Months Ended
	Jan. 31, 2018	Jul. 31, 2017
Accrued Expenses and Other Current Liabilities [Line Items]
Accrued pricing liabilities	$ 18,882	$ 18,882
Other long-term liabilities	30,693	$ 9,414
IWCO | Sales Tax Liabilities
Accrued Expenses and Other Current Liabilities [Line Items]
Other long-term liabilities	18,000
IWCO | Sales Tax Liabilities
Accrued Expenses and Other Current Liabilities [Line Items]
Reserve recorded	$ 18,000