Supplementary Balance Sheet Information (Components Of Accounts Payable And Accrued Liabilities) (Details) - USD ($) $ in Thousands	Jan. 31, 2016	Jul. 31, 2015	Jan. 31, 2015
Balance Sheet Related Disclosures [Abstract]
Trade payables	$ 82,913	$ 62,099	$ 87,864
Deferred revenue	190,976	145,949	163,253
Accrued salaries, wages and deferred compensation	43,916	33,461	41,710
Accrued benefits	26,199	24,436	22,304
Deposits	36,995	19,336	33,709
Other accruals	66,771	46,018	71,989
Total accounts payable and accrued liabilities	$ 447,770	$ 331,299	$ 420,829