Supplementary Balance Sheet Information (Components Of Accounts Payable And Accrued Liabilities) (Details) - USD ($) $ in Thousands	Oct. 31, 2015	Jul. 31, 2015	Oct. 31, 2014
Balance Sheet Related Disclosures [Abstract]
Trade payables	$ 101,016	$ 62,099	$ 94,035
Deferred revenue	240,288	145,949	198,133
Accrued salaries, wages and deferred compensation	11,878	33,461	18,379
Accrued benefits	22,818	24,436	20,046
Deposits	15,979	19,336	14,614
Other accruals	46,858	46,018	45,063
Total accounts payable and accrued liabilities	$ 438,837	$ 331,299	$ 390,270