Segment Information - Results by Reportable Segment (Details) $ in Millions	3 Months Ended
Oct. 31, 2019 USD ($) segment	Oct. 31, 2018 USD ($)
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	$ 1,165	$ 1,016
Total operating income (loss)	10	(10)
Unallocated corporate items:
Share-based compensation expense	(111)	(105)
Amortization of acquired technology	(6)	(5)
Amortization of other acquired intangible assets	(2)	(2)
Operating Segments
Financial results by reportable segment
Total operating income (loss)	484	399
Segment Reconciling Items
Unallocated corporate items:
Share-based compensation expense	(111)	(105)
Other common expenses	(355)	(297)
Amortization of acquired technology	(6)	(5)
Amortization of other acquired intangible assets	(2)	(2)
Total unallocated corporate items	(474)	(409)
Small Business & Self-Employed
Financial results by reportable segment
Revenues	1,046	908
Small Business & Self-Employed \| Operating Segments
Financial results by reportable segment
Total operating income (loss)	550	460
Consumer
Financial results by reportable segment
Revenues	100	90
Consumer \| Operating Segments
Financial results by reportable segment
Total operating income (loss)	(45)	(41)
Strategic Partner
Financial results by reportable segment
Revenues	19	18
Strategic Partner \| Operating Segments
Financial results by reportable segment
Total operating income (loss)	$ (21)	$ (20)

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