REVENUE, DEFERRED REVENUE AND DEFERRED COMMISSIONS - Schedule of Revenue (Details) - USD ($) $ in Thousands	3 Months Ended			6 Months Ended
	Jan. 31, 2018	Jan. 31, 2017		Jan. 31, 2018	Jan. 31, 2017
Condensed Income Statements, Captions [Line Items]
Sales revenue, goods	$ 223,170	$ 158,213		$ 442,222	$ 311,749
Support and other services	63,574	41,001		120,074	76,026
Total revenue	286,744	199,214	[1]	562,296	387,775
Software
Condensed Income Statements, Captions [Line Items]
Sales revenue, goods	145,171	102,845		283,385	207,590
Hardware
Condensed Income Statements, Captions [Line Items]
Sales revenue, goods	$ 77,999	55,368		$ 158,837	104,159
Accounting Standards Update 2014-09
Condensed Income Statements, Captions [Line Items]
Sales revenue, goods		158,213			311,749
Support and other services		41,001			76,026
Total revenue		$ 199,214			$ 387,775

[1] See Note 3 for a summary of adjustments related to the adoption of the new revenue recognition standard.