Postretirement Plans - Schedule of Asset Allocations (Details) - Vencore Holding Corp. and KGS Holding Corp. - Pension Plan - Qualified Plan	Mar. 30, 2018
Cash and cash equivalents
Defined Benefit Plan Disclosure [Line Items]
Target Allocation 2018	2.50%
Actual Allocation 2017	0.90%
Equity securities
Defined Benefit Plan Disclosure [Line Items]
Target Allocation 2018	30.00%
Actual Allocation 2017	31.00%
Fixed income
Defined Benefit Plan Disclosure [Line Items]
Target Allocation 2018	22.50%
Actual Allocation 2017	24.80%
Real estate
Defined Benefit Plan Disclosure [Line Items]
Target Allocation 2018	10.00%
Actual Allocation 2017	11.90%
Other
Defined Benefit Plan Disclosure [Line Items]
Target Allocation 2018	35.00%
Actual Allocation 2017	31.40%

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Percentage of target investment allocation to total plan assets. Includes, but is not limited to, percentage on weighted-average basis if more than one plan.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 715
-SubTopic 20
-Section 50
-Paragraph 1
-Subparagraph (d)(5)(i)
-URI http://asc.fasb.org/extlink&oid=82843861&loc=d3e1928-114920

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Percentage of fair value of investments (categorized by debt securities, equity securities, real estate and other plan assets) to the fair value of plan assets held.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 715
-SubTopic 20
-Section 50
-Paragraph 5
-Subparagraph (c)
-URI http://asc.fasb.org/extlink&oid=82843861&loc=d3e2446-114920

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-Publisher FASB
-Name Accounting Standards Codification
-Topic 715
-SubTopic 20
-Section 50
-Paragraph 1
-Subparagraph (d)(1)
-URI http://asc.fasb.org/extlink&oid=82843861&loc=d3e1928-114920

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