Acquisitions and Divestitures (Summary of Intangible Assets Acquired) (Details) - Pure $ in Millions	Jan. 31, 2018 USD ($)
Business Acquisition [Line Items]
Intangible assets	$ 149
Customer Relationships
Business Acquisition [Line Items]
Intangible assets	84
Technology
Business Acquisition [Line Items]
Intangible assets	38
Tradenames
Business Acquisition [Line Items]
Intangible assets	21
Software Development
Business Acquisition [Line Items]
Intangible assets	$ 6
Minimum \| Customer Relationships
Business Acquisition [Line Items]
Life	17 years
Minimum \| Technology
Business Acquisition [Line Items]
Life	3 years
Maximum \| Customer Relationships
Business Acquisition [Line Items]
Life	18 years
Maximum \| Technology
Business Acquisition [Line Items]
Life	10 years

Weighted average amortization period of finite-lived intangible assets acquired either individually or as part of a group of assets, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days.

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 350
-SubTopic 30
-Section 50
-Paragraph 1
-Subparagraph (a)(3)
-URI http://asc.fasb.org/extlink&oid=66006027&loc=d3e16265-109275

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- Definition

Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table.

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- Definition

Amount of intangible assets, excluding goodwill, acquired at the acquisition date.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 805
-SubTopic 20
-Section 50
-Paragraph 1
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-URI http://asc.fasb.org/extlink&oid=121647850&loc=d3e4845-128472

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