Overview and Basis of Presentation (Details) $ in Millions		3 Months Ended	9 Months Ended
May 31, 2018 USD ($)	Dec. 31, 2018 USD ($)	Dec. 31, 2018 USD ($) segment
Business Acquisition [Line Items]
Number of reportable segments \| segment			2
Revenue from related parties		$ 3	$ 9
Expenses from transactions with related parties		$ 27	$ 39
Vencore and KeyPoint
Business Acquisition [Line Items]
Payments for acquisitions, net of cash acquired	$ 400
Shares issued in a business acquisition as a percentage of outstanding shares	14.00%

Business Acquisition, Equity Interest Issued or Issuable, Percentage Of Number of Shares Outstanding

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

Costs of sales and operating expenses for the period incurred from transactions with related parties.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 220
-SubTopic 10
-Section S99
-Paragraph 2
-Subparagraph (SX 210.5-03.2)
-URI http://asc.fasb.org/extlink&oid=115205541&loc=SL114868664-224227

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- Definition

Number of segments reported by the entity. A reportable segment is a component of an entity for which there is an accounting requirement to report separate financial information on that component in the entity's financial statements.

+ References

No definition available.

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- Definition

The cash outflow associated with the acquisition of business during the period. The cash portion only of the acquisition price.

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 805
-SubTopic 30
-Section 50
-Paragraph 1
-Subparagraph (b)(1)
-URI http://asc.fasb.org/extlink&oid=35744584&loc=d3e6927-128479

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-Topic 230
-SubTopic 10
-Section 45
-Paragraph 13
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-URI http://asc.fasb.org/extlink&oid=109223946&loc=d3e3213-108585

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- Definition

Amount of revenue, fees and commissions earned from transactions between (a) a parent company and its subsidiaries; (b) subsidiaries of a common parent; (c) an entity and trusts for the benefit of employees, for example, but not limited to, pension and profit-sharing trusts that are managed by or under the trusteeship of the entity's management; (d) an entity and its principal, owners, management, or members of their immediate families; and (e) affiliates.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
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-Topic 946
-SubTopic 220
-Section S99
-Paragraph 1
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