Accounts Payable and Accrued Liabilities (Details) - USD ($) $ in Thousands	Jul. 31, 2020	Jul. 31, 2019
Payables and Accruals [Abstract]
Accounts payable to sellers	$ 92,013	$ 68,427
Buyer deposits and prepayments	89,020	73,421
Trade accounts payable	40,906	45,520
Accrued compensation and benefits	42,053	41,400
Taxes payable	17,036	3,881
Accrued insurance	9,315	8,507
Other accrued liabilities	28,187	29,762
Total accounts payable and accrued expenses	$ 318,530	$ 270,918