Nature of Operations and Accounting Policies - Additional Information (Detail) - USD ($) $ in Thousands	3 Months Ended
	Oct. 31, 2018	Aug. 01, 2018
Nature Of Operations And Significant Accounting Policies [Line Items]
Cumulative effect of the change in accounting principle, net of tax	$ (5,450)
Accounting Standards Update 2014-09 | Retained Earnings
Nature Of Operations And Significant Accounting Policies [Line Items]
Cumulative effect of the change in accounting principle, net of tax		$ (5,450)
Accounting Standards Update 2014-09 | Accrued Promotions and Rebates
Nature Of Operations And Significant Accounting Policies [Line Items]
Cumulative effect of the change in accounting principle, net of tax		7,127
Cumulative effect of change on equity or net assets on pre-tax basis	$ 733
Accounting Standards Update 2014-09 | Deferred Income Tax Assets
Nature Of Operations And Significant Accounting Policies [Line Items]
Cumulative effect of the change in accounting principle, net of tax		$ 1,677