Supplementary Balance Sheet Information (Components Of Accounts Payable And Accrued Liabilities) (Details) - USD ($) $ in Thousands	Jul. 31, 2019	Jul. 31, 2018
Balance Sheet Related Disclosures [Abstract]
Trade payables	$ 96,377	$ 80,793
Deferred Revenue, Current	335,669	282,103
Accrued salaries, wages and deferred compensation	50,318	40,034
Accrued benefits	37,797	33,963
Deposits	32,108	26,646
Other accruals	55,588	40,994
Total accounts payable and accrued liabilities	$ 607,857	$ 504,533