Leases (Supplemental Lease Information) (Details) - USD ($) $ in Thousands	Jan. 31, 2020	Jul. 31, 2019
Assets and Liabilities, Lessee [Abstract]
Operating lease assets	$ 88,520
Current portion of lease liabilities	9,824	$ 0
Non-current portion of lease liabilities	102,083
Total lease liabilities	$ 111,907
Weighted average remaining lease term (years)	9 years 3 months 3 days
Weighted average discount rate	4.35%