Segment Information - Results by Reportable Segment (Details) $ in Millions	3 Months Ended	6 Months Ended
Jan. 31, 2019 USD ($)	Jan. 31, 2018 USD ($)	Jan. 31, 2019 USD ($) segment	Jan. 31, 2018 USD ($)
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%
Financial results by reportable segment
Revenues	$ 1,502	$ 1,339	$ 2,518	$ 2,249
Total operating income	233	194	223	159
Unallocated corporate items:
Share-based compensation expense	(100)	(94)	(205)	(191)
Amortization of acquired technology	(5)	(3)	(10)	(5)
Amortization of other acquired intangible assets	(1)	(1)	(3)	(2)
Operating Segments
Financial results by reportable segment
Total operating income	650	573	1,049	913
Segment Reconciling Items
Unallocated corporate items:
Share-based compensation expense	(100)	(94)	(205)	(191)
Other common expenses	(311)	(281)	(608)	(556)
Amortization of acquired technology	(5)	(3)	(10)	(5)
Amortization of other acquired intangible assets	(1)	(1)	(3)	(2)
Total unallocated corporate items	(417)	(379)	(826)	(754)
Small Business & Self-Employed
Financial results by reportable segment
Revenues	833	713	1,741	1,532
Small Business & Self-Employed \| Operating Segments
Financial results by reportable segment
Total operating income	320	258	780	682
Consumer
Financial results by reportable segment
Revenues	461	416	551	490
Consumer \| Operating Segments
Financial results by reportable segment
Total operating income	164	151	123	92
Strategic Partner
Financial results by reportable segment
Revenues	208	210	226	227
Strategic Partner \| Operating Segments
Financial results by reportable segment
Total operating income	$ 166	$ 164	$ 146	$ 139

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