Subsequent Event Subsequent Events (Narrative) (Details) - Subsequent Event [Member] $ in Millions	3 Months Ended
Oct. 28, 2017 employess	Aug. 11, 2017 USD ($)
Subsequent Event [Line Items]
Employees excluding Q4 activities \| employess	4,600
Employee Severance [Member] \| Q4 2017 Involuntary Severance Plan [Member]
Subsequent Event [Line Items]
Restructuring and Related Activities, Initiation Date	Aug. 11, 2017
Restructuring and Related Cost, Expected Number of Positions Eliminated \| employess	230
Employee Severance [Member] \| Q4 2017 Involuntary Severance Plan [Member] \| Minimum [Member]
Subsequent Event [Line Items]
Restructuring and Related Cost, Expected Cost \| $		$ 23
Employee Severance [Member] \| Q4 2017 Involuntary Severance Plan [Member] \| Maximum [Member]
Subsequent Event [Line Items]
Restructuring and Related Cost, Expected Cost \| $		$ 26

Number of employees excluding employees notified for Q4 severance or software divestitures

No definition available.

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- Definition

Date the restructuring activities were initiated or are expected to be initiated, in CCYY-MM-DD format.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 420
-SubTopic 10
-Section 50
-Paragraph 1
-Subparagraph (a)
-URI http://asc.fasb.org/extlink&oid=6394359&loc=d3e17939-110869

Reference 2: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 420
-SubTopic 10
-Section S99
-Paragraph 2
-Subparagraph (SAB Topic 5.P.4(a))
-URI http://asc.fasb.org/extlink&oid=27011515&loc=d3e140904-122747

+ Details

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Balance Type:	na
Period Type:	duration

- Definition

Amount expected to be recognized in earnings for the specified restructuring cost.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 420
-SubTopic 10
-Section 50
-Paragraph 1
-Subparagraph (b)
-URI http://asc.fasb.org/extlink&oid=6394359&loc=d3e17939-110869

Reference 2: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 420
-SubTopic 10
-Section S99
-Paragraph 2
-Subparagraph (SAB Topic 5.P.4(b))
-URI http://asc.fasb.org/extlink&oid=27011515&loc=d3e140904-122747

+ Details

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- Definition

The expected number of positions to be eliminated as a result of restructuring activities.

+ References

No definition available.

+ Details

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- Definition

Detail information of subsequent event by type. User is expected to use existing line items from elsewhere in the taxonomy as the primary line items for this disclosure, which is further associated with dimension and member elements pertaining to a subsequent event.

+ References

No definition available.

+ Details

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- Details

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- Details

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- Details

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