Segment Information (Details) $ in Millions	3 Months Ended	9 Months Ended
Apr. 30, 2018 USD ($)	Apr. 30, 2017 USD ($)	Apr. 30, 2018 USD ($) segment	Apr. 30, 2017 USD ($)
Segment Reporting Information [Line Items]
Number of reportable segments \| segment			3
International total net revenue as a percentage of total (less than)	5.00%	5.00%
Financial results by reportable segment
Total net revenue	$ 2,925	$ 2,541	$ 4,976	$ 4,335
Total operating income	1,615	1,444	1,578	1,405
Unallocated corporate items:
Share-based compensation expense			(283)	(241)
Amortization of acquired technology and other acquired intangible assets	(2)	(1)	(4)	(2)
Operating Segments
Financial results by reportable segment
Total operating income	2,017	1,778	2,734	2,395
Corporate, Non-Segment
Financial results by reportable segment
Total operating income	(402)	(334)	(1,156)	(990)
Unallocated corporate items:
Share-based compensation expense	(92)	(71)	(283)	(241)
Other common expenses	(303)	(259)	(859)	(738)
Corporate, Non-Segment \| Technology-Based Intangible Assets
Unallocated corporate items:
Amortization of acquired technology and other acquired intangible assets	(5)	(3)	(10)	(9)
Corporate, Non-Segment \| Other Intangible Assets
Unallocated corporate items:
Amortization of acquired technology and other acquired intangible assets	(2)	(1)	(4)	(2)
Small Business & Self-Employed
Financial results by reportable segment
Total net revenue	759	655	2,189	1,866
Small Business & Self-Employed \| Operating Segments
Financial results by reportable segment
Total operating income	292	276	874	756
Consumer
Financial results by reportable segment
Total net revenue	2,035	1,770	2,447	2,142
Consumer \| Operating Segments
Financial results by reportable segment
Total operating income	1,636	1,429	1,650	1,446
Strategic Partner
Financial results by reportable segment
Total net revenue	131	116	340	327
Strategic Partner \| Operating Segments
Financial results by reportable segment
Total operating income	$ 89	$ 73	$ 210	$ 193

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