Segment Information (Details) $ in Millions	3 Months Ended	9 Months Ended
Apr. 30, 2017 USD ($)	Apr. 30, 2016 USD ($)	Apr. 30, 2017 USD ($) segment	Apr. 30, 2016 USD ($)
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%	5.00%	5.00%
Financial results by reportable segment
Total net revenue	$ 2,541	$ 2,304	$ 4,335	$ 3,940
Total operating income from continuing operations	1,444	1,285	1,405	1,298
Unallocated corporate items:
Share-based compensation expense			(241)	(200)
Amortization of other acquired intangible assets	(1)	(3)	(2)	(6)
Operating Segments
Financial results by reportable segment
Total operating income from continuing operations	1,778	1,602	2,395	2,170
Corporate, Non-Segment
Financial results by reportable segment
Total operating income from continuing operations	(334)	(317)	(990)	(872)
Unallocated corporate items:
Share-based compensation expense	(71)	(65)	(241)	(197)
Other common expenses	(259)	(244)	(738)	(652)
Corporate, Non-Segment \| Technology-Based Intangible Assets
Unallocated corporate items:
Amortization of other acquired intangible assets	(3)	(5)	(9)	(17)
Corporate, Non-Segment \| Other Intangible Assets
Unallocated corporate items:
Amortization of other acquired intangible assets	(1)	(3)	(2)	(6)
Small Business
Financial results by reportable segment
Total net revenue	671	580	1,909	1,690
Small Business \| Operating Segments
Financial results by reportable segment
Total operating income from continuing operations	277	223	758	643
Consumer Tax
Financial results by reportable segment
Total net revenue	1,754	1,598	2,099	1,930
Consumer Tax \| Operating Segments
Financial results by reportable segment
Total operating income from continuing operations	1,428	1,293	1,444	1,328
ProConnect
Financial results by reportable segment
Total net revenue	116	126	327	320
ProConnect \| Operating Segments
Financial results by reportable segment
Total operating income from continuing operations	$ 73	$ 86	$ 193	$ 199

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