Segment Information - Results by Reportable Segment (Details) $ in Millions	3 Months Ended	6 Months Ended
Jan. 31, 2020 USD ($)	Jan. 31, 2019 USD ($)	Jan. 31, 2020 USD ($) segment	Jan. 31, 2019 USD ($)
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%
Financial results by reportable segment
Revenues	$ 1,696	$ 1,502	$ 2,861	$ 2,518
Total operating income	270	233	280	223
Unallocated corporate items:
Share-based compensation expense	(107)	(100)	(218)	(205)
Amortization of acquired technology	(6)	(5)	(12)	(10)
Amortization of other acquired intangible assets	(1)	(1)	(3)	(3)
Operating Segments
Financial results by reportable segment
Total operating income	747	650	1,231	1,049
Segment Reconciling Items
Unallocated corporate items:
Share-based compensation expense	(107)	(100)	(218)	(205)
Other common expenses	(363)	(311)	(718)	(608)
Amortization of acquired technology	(6)	(5)	(12)	(10)
Amortization of other acquired intangible assets	(1)	(1)	(3)	(3)
Total unallocated corporate items	(477)	(417)	(951)	(826)
Small Business & Self-Employed
Financial results by reportable segment
Revenues	973	833	2,019	1,741
Small Business & Self-Employed \| Operating Segments
Financial results by reportable segment
Total operating income	402	320	952	780
Consumer
Financial results by reportable segment
Revenues	499	461	599	551
Consumer \| Operating Segments
Financial results by reportable segment
Total operating income	163	164	118	123
Strategic Partner
Financial results by reportable segment
Revenues	224	208	243	226
Strategic Partner \| Operating Segments
Financial results by reportable segment
Total operating income	$ 182	$ 166	$ 161	$ 146

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