Acquisitions - HPES Narrative (Details) - Hewlett Packard Enterprise Services $ in Millions	12 Months Ended
Mar. 31, 2018 USD ($)
Business Acquisition [Line Items]
Total fair value of consideration transferred for USPS	$ 2,850
Valuation adjustments, estimated fair value, increase in net assets	5
Valuation adjustments, estimated fair value, increase in total assets	10
Valuation adjustments, estimated fair value, increase in intangible assets	70
Valuation adjustments, estimated fair value, increase in current assets	9
Valuation adjustments, estimated fair value, decrease in property and equipment	68
Valuation adjustments, estimated fair value, increase in current capital lease liability	$ 5

Business Combination, Provisional Information, Initial Accounting Incomplete, Adjustment, Assets

No definition available.

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- Definition

Business Combination, Provisional Information, Initial Accounting Incomplete, Adjustment, Liabilities

+ References

No definition available.

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- Definition

Business Combination, Provisional Information, Initial Accounting Incomplete, Adjustment, Net Assets

+ References

No definition available.

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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.

+ References

No definition available.

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- Definition

This element represents the amount of any measurement period adjustment (as defined) realized during the reporting period to financial assets acquired in connection with a business combination for which the initial accounting was incomplete.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 805
-SubTopic 20
-Section 50
-Paragraph 4A
-Subparagraph (c)
-URI http://asc.fasb.org/extlink&oid=84161108&loc=SL65897772-128472

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- Definition

This element represents the amount of any measurement period adjustment (as defined) realized during the reporting period to intangibles acquired in connection with a business combination for which the initial accounting was incomplete.

+ References

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- Definition

This element represents the amount of any measurement period adjustment (as defined) realized during the reporting period to property, plant, and equipment acquired in connection with a business combination for which the initial accounting was incomplete.

+ References

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- Definition

Amount recognized as of the acquisition date for the assets, including goodwill, in excess of (less than) the aggregate liabilities assumed, less the noncontrolling interest in the acquiree.

+ 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
-Subparagraph (c)
-URI http://asc.fasb.org/extlink&oid=84161108&loc=d3e4845-128472

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