Goodwill and Acquired Intangible Assets - Goodwill (Details) - USD ($) $ in Millions	12 Months Ended
Jul. 31, 2017	Jul. 31, 2016	Jul. 31, 2015
Goodwill [Roll Forward]
Goodwill, beginning	$ 1,282	$ 1,266
Goodwill Acquired/ Adjusted	13	16
Goodwill, ending	1,295	1,282
Small Business
Goodwill [Roll Forward]
Goodwill, beginning	1,173	1,157
Goodwill Acquired/ Adjusted	12	16
Goodwill, ending	1,185	1,173
Goodwill net of accumulated impairment losses			$ 114
Consumer Tax
Goodwill [Roll Forward]
Goodwill, beginning	18	18
Goodwill Acquired/ Adjusted	0	0
Goodwill, ending	18	18
ProConnect
Goodwill [Roll Forward]
Goodwill, beginning	91	91
Goodwill Acquired/ Adjusted	1	0
Goodwill, ending	$ 92	$ 91

Amount after accumulated impairment loss of an asset representing future economic benefits arising from other assets acquired in a business combination that are not individually identified and separately recognized.

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 350
-SubTopic 20
-Section 50
-Paragraph 1
-Subparagraph (a)
-URI http://asc.fasb.org/extlink&oid=35741047&loc=d3e13816-109267

Reference 2: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 350
-SubTopic 20
-Section 45
-Paragraph 1
-URI http://asc.fasb.org/extlink&oid=6388280&loc=d3e13770-109266

Reference 3: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 350
-SubTopic 20
-Section 45
-Paragraph 5
-URI http://asc.fasb.org/extlink&oid=77989000&loc=SL49117168-202975

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- Definition

Amount of accumulated impairment loss for an asset representing future economic benefits arising from other assets acquired in a business combination that are not individually identified and separately recognized.

+ References

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- Definition

Amount of increase (decrease) of an asset representing future economic benefits arising from other assets acquired in a business combination that are not individually identified and separately recognized.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 350
-SubTopic 20
-Section 50
-Paragraph 1
-URI http://asc.fasb.org/extlink&oid=35741047&loc=d3e13816-109267

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- Definition

A roll forward is a reconciliation of a concept from the beginning of a period to the end of a period.

+ References

No definition available.

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