Segment Information - Results by Reportable Segment (Details) $ in Millions	3 Months Ended
Oct. 31, 2018 USD ($) segment	Oct. 31, 2017 USD ($)
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	$ 1,016	$ 910
Total operating loss	(10)	(35)
Unallocated corporate items:
Share-based compensation expense	(105)	(97)
Amortization of acquired technology	(5)	(2)
Amortization of other acquired intangible assets	(2)	(1)
Operating Segments
Financial results by reportable segment
Total operating loss	399	340
Segment Reconciling Items
Unallocated corporate items:
Share-based compensation expense	(105)	(97)
Other common expenses	(297)	(275)
Amortization of acquired technology	(5)	(2)
Amortization of other acquired intangible assets	(2)	(1)
Total unallocated corporate items	(409)	(375)
Small Business & Self-Employed
Financial results by reportable segment
Revenues	908	819
Small Business & Self-Employed \| Operating Segments
Financial results by reportable segment
Total operating loss	460	424
Consumer
Financial results by reportable segment
Revenues	90	74
Consumer \| Operating Segments
Financial results by reportable segment
Total operating loss	(41)	(59)
Strategic Partner
Financial results by reportable segment
Revenues	18	17
Strategic Partner \| Operating Segments
Financial results by reportable segment
Total operating loss	$ (20)	$ (25)

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