Leases - Lease Expenses (Details) - USD ($) $ in Thousands	12 Months Ended
	Jul. 31, 2022	Jul. 31, 2021	Jul. 31, 2020
Lease, Cost [Abstract]
Operating lease expense	$ 30,340	$ 36,170	$ 41,487
Short-term expense	9,502	8,727	7,690
Variable lease expense	5,258	3,875	4,525
Total finance lease expense	9,565	12,633	3,673
Total lease expense	54,665	61,405	57,375
Operating expenses - personnel, vehicle, plant and other
Lease, Cost [Abstract]
Operating lease expense	6,832	7,695	7,450
Short-term expense	9,231	8,151	7,188
Variable lease expense	3,096	2,328	2,883
Operating expense - equipment lease expense
Lease, Cost [Abstract]
Operating lease expense	20,291	26,127	30,994
Variable lease expense	2,162	1,547	1,642
Cost of Sales [Member]
Lease, Cost [Abstract]
Operating lease expense	1,630	1,911	1,553
General and Administrative Expense [Member]
Lease, Cost [Abstract]
Operating lease expense	1,587	437	1,490
Short-term expense	271	576	502
Depreciation And Amortization Expense [Member]
Lease, Cost [Abstract]
Amortization of leased assets	6,660	8,878	2,613
Interest Expense [Member]
Lease, Cost [Abstract]
Interest on lease liabilities	$ 2,905	$ 3,755	$ 1,060