Segment Information - Results by Reportable Segment (Details) $ in Millions	3 Months Ended	9 Months Ended
Apr. 30, 2019 USD ($)	Apr. 30, 2018 USD ($)	Apr. 30, 2019 USD ($) segment	Apr. 30, 2018 USD ($)
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%	5.00%
Financial results by reportable segment
Revenues	$ 3,272	$ 2,912	$ 5,790	$ 5,161
Total operating income	1,784	1,601	2,007	1,760
Unallocated corporate items:
Share-based compensation expense	(98)	(92)	(303)	(283)
Amortization of acquired technology	(5)	(5)	(15)	(10)
Amortization of other acquired intangible assets	(1)	(2)	(4)	(4)
Operating Segments
Financial results by reportable segment
Total operating income	2,248	2,003	3,297	2,916
Segment Reconciling Items
Unallocated corporate items:
Share-based compensation expense	(98)	(92)	(303)	(283)
Other common expenses	(360)	(303)	(968)	(859)
Amortization of acquired technology	(5)	(5)	(15)	(10)
Amortization of other acquired intangible assets	(1)	(2)	(4)	(4)
Total unallocated corporate items	(464)	(402)	(1,290)	(1,156)
Small Business & Self-Employed
Financial results by reportable segment
Revenues	887	747	2,628	2,279
Small Business & Self-Employed \| Operating Segments
Financial results by reportable segment
Total operating income	375	280	1,155	962
Consumer
Financial results by reportable segment
Revenues	2,150	1,949	2,701	2,439
Consumer \| Operating Segments
Financial results by reportable segment
Total operating income	1,678	1,550	1,801	1,642
Strategic Partner
Financial results by reportable segment
Revenues	235	216	461	443
Strategic Partner \| Operating Segments
Financial results by reportable segment
Total operating income	$ 195	$ 173	$ 341	$ 312

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