Goodwill (Schedule of Changes in Goodwill by Segment) (Detail) - USD ($) $ in Millions	3 Months Ended	12 Months Ended
Mar. 31, 2017	Dec. 30, 2016
Goodwill [Roll Forward]
Beginning balance, Goodwill	$ 4,622	$ 1,207
Acquisition of the IS&GS Business		3,415
Adjustment to original purchase price allocation	(3)
Ending balance, Goodwill	4,619	4,622
Defense Solutions
Goodwill [Roll Forward]
Beginning balance, Goodwill	1,954	792
Acquisition of the IS&GS Business		1,162
Adjustment to original purchase price allocation	(1)
Ending balance, Goodwill	1,953	1,954
Civil
Goodwill [Roll Forward]
Beginning balance, Goodwill	1,731	244
Acquisition of the IS&GS Business		1,487
Adjustment to original purchase price allocation	(1)
Ending balance, Goodwill	1,730	1,731
Health
Goodwill [Roll Forward]
Beginning balance, Goodwill	937	171
Acquisition of the IS&GS Business		766
Adjustment to original purchase price allocation	(1)
Ending balance, Goodwill	$ 936	$ 937

Amount after accumulated impairment loss of an asset representing future economic benefits arising from other assets acquired in a business combination that are not individually identified and separately recognized.

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 350
-SubTopic 20
-Section 50
-Paragraph 1
-Subparagraph (a)
-URI http://asc.fasb.org/extlink&oid=35741047&loc=d3e13816-109267

Reference 2: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 350
-SubTopic 20
-Section 45
-Paragraph 1
-URI http://asc.fasb.org/extlink&oid=6388280&loc=d3e13770-109266

Reference 3: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 350
-SubTopic 20
-Section 45
-Paragraph 5
-URI http://asc.fasb.org/extlink&oid=64834752&loc=SL49117168-202975

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Amount of increase in asset representing future economic benefits arising from other assets acquired in a business combination that are not individually identified and separately recognized resulting from a business combination.

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Amount of increase (decrease) from foreign currency translation adjustments and purchase accounting adjustments of an asset representing future economic benefits arising from other assets acquired in a business combination that are not individually identified and separately recognized.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 350
-SubTopic 20
-Section 50
-Paragraph 1
-Subparagraph (g)
-URI http://asc.fasb.org/extlink&oid=35741047&loc=d3e13816-109267

Reference 2: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 805
-SubTopic 10
-Section 25
-Paragraph 16
-URI http://asc.fasb.org/extlink&oid=73531572&loc=d3e961-128460

Reference 3: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 350
-SubTopic 20
-Section 50
-Paragraph 1
-Subparagraph (f)
-URI http://asc.fasb.org/extlink&oid=35741047&loc=d3e13816-109267

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