Nature of Operations and Accounting Policies (Detail) - USD ($) $ in Thousands	Apr. 30, 2020	Aug. 01, 2019
Nature Of Operations And Significant Accounting Policies [Line Items]
Operating lease right-of-use assets	$ 31,997
Operating lease liability	$ 32,163
Accounting Standards Update 2016-02
Nature Of Operations And Significant Accounting Policies [Line Items]
Operating lease right-of-use assets		$ 33,000
Operating lease liability		$ 33,000