Debt - Schedule of Long-Term Debt (Details) - USD ($) $ in Thousands	12 Months Ended
	Jul. 31, 2020	Jul. 31, 2019
Debt Instrument [Line Items]
Current maturities on long-term debt	$ 0	$ 50,166
Long-term debt		50,166
Letters of credit outstanding	3,116	$ 3,271
Line of credit facility, maximum amount outstanding during period	16,200
Line of credit, remaining borrowing capacity	196,900
Line of credit, maximum borrowing capacity	$ 396,900