Revenue Recognition - Narrative (Details) - USD ($) $ in Thousands	Jul. 31, 2020	Jul. 31, 2019	Aug. 01, 2018
New Accounting Pronouncements or Change in Accounting Principle [Line Items]
Retained earnings	$ 548,334	$ 539,097
Difference between Revenue Guidance in Effect before and after Topic 606 | Accounting Standards Update 2014-09
New Accounting Pronouncements or Change in Accounting Principle [Line Items]
Retained earnings			$ 865
Minimum
New Accounting Pronouncements or Change in Accounting Principle [Line Items]
Capitalized contract cost, amortization period	2 years
Maximum
New Accounting Pronouncements or Change in Accounting Principle [Line Items]
Capitalized contract cost, amortization period	5 years