Segment Information - Results by Reportable Segment (Details) $ in Millions	3 Months Ended	9 Months Ended
Apr. 30, 2020 USD ($)	Apr. 30, 2019 USD ($)	Apr. 30, 2020 USD ($) segment	Apr. 30, 2019 USD ($)
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%	5.00%
Financial results by reportable segment
Revenues	$ 3,002	$ 3,272	$ 5,863	$ 5,790
Total operating income	1,413	1,784	1,693	2,007
Unallocated corporate items:
Share-based compensation expense	(103)	(98)	(321)	(303)
Amortization of acquired technology	(5)	(5)	(17)	(15)
Amortization of other acquired intangible assets	(2)	(1)	(5)	(4)
Operating Segments
Financial results by reportable segment
Total operating income	1,886	2,248	3,117	3,297
Segment Reconciling Items
Unallocated corporate items:
Share-based compensation expense	(103)	(98)	(321)	(303)
Other common expenses	(363)	(360)	(1,081)	(968)
Amortization of acquired technology	(5)	(5)	(17)	(15)
Amortization of other acquired intangible assets	(2)	(1)	(5)	(4)
Total unallocated corporate items	(473)	(464)	(1,424)	(1,290)
Small Business & Self-Employed
Financial results by reportable segment
Revenues	982	887	3,001	2,628
Small Business & Self-Employed \| Operating Segments
Financial results by reportable segment
Total operating income	413	375	1,365	1,155
Consumer
Financial results by reportable segment
Revenues	1,827	2,150	2,426	2,701
Consumer \| Operating Segments
Financial results by reportable segment
Total operating income	1,321	1,678	1,439	1,801
Strategic Partner
Financial results by reportable segment
Revenues	193	235	436	461
Strategic Partner \| Operating Segments
Financial results by reportable segment
Total operating income	$ 152	$ 195	$ 313	$ 341

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