Segment Information (Details) $ in Millions	3 Months Ended
Oct. 31, 2017 USD ($) segment	Oct. 31, 2016 USD ($)
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
Total net revenue	$ 886	$ 778
Total operating loss	(57)	(61)
Unallocated corporate items:
Share-based compensation expense	(97)	(89)
Amortization of other acquired intangible assets	(1)	(1)
Operating Segments
Financial results by reportable segment
Total operating loss	318	271
Corporate, Non-Segment
Financial results by reportable segment
Total operating loss	(375)	(332)
Unallocated corporate items:
Share-based compensation expense	(97)	(89)
Other common expenses	(275)	(239)
Corporate, Non-Segment \| Technology-Based Intangible Assets
Unallocated corporate items:
Amortization of other acquired intangible assets	(2)	(3)
Corporate, Non-Segment \| Other Intangible Assets
Unallocated corporate items:
Amortization of other acquired intangible assets	(1)	(1)
Small Business & Self-Employed
Financial results by reportable segment
Total net revenue	694	593
Small Business & Self-Employed \| Operating Segments
Financial results by reportable segment
Total operating loss	301	239
Consumer
Financial results by reportable segment
Total net revenue	78	73
Consumer \| Operating Segments
Financial results by reportable segment
Total operating loss	(55)	(38)
Strategic Partner
Financial results by reportable segment
Total net revenue	114	112
Strategic Partner \| Operating Segments
Financial results by reportable segment
Total operating loss	$ 72	$ 70

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