Goodwill and Intangible Assets (Changes in Goodwill by Segment) (Details) - USD ($) $ in Millions	12 Months Ended
Jan. 03, 2025	Dec. 29, 2023	Dec. 30, 2022
Goodwill [Roll Forward]
Beginning balance	$ 6,112	$ 6,696
Goodwill impairment	0	(596)	$ 0
Acquisitions of a business		(4)
Foreign currency translation adjustments	(28)	16
Ending balance	6,084	6,112	6,696
National Security & Digital
Goodwill [Roll Forward]
Beginning balance	2,758	2,755
Goodwill impairment		0
Acquisitions of a business		0
Foreign currency translation adjustments	0	3
Ending balance	2,758	2,758	2,755
Health & Civil
Goodwill [Roll Forward]
Beginning balance	1,366	1,366
Goodwill impairment		0
Acquisitions of a business		0
Foreign currency translation adjustments	0	0
Ending balance	1,366	1,366	1,366
Commercial & International
Goodwill [Roll Forward]
Beginning balance	800	1,389
Goodwill impairment		(596)
Acquisitions of a business		(4)
Foreign currency translation adjustments	(28)	11
Ending balance	772	800	1,389
Accumulated goodwill impairment losses		596
Defense Systems
Goodwill [Roll Forward]
Beginning balance	1,188	1,186
Goodwill impairment		0
Acquisitions of a business		0
Foreign currency translation adjustments	0	2
Ending balance	$ 1,188	$ 1,188	$ 1,186

Amount, after accumulated impairment loss, of asset representing future economic benefit arising from other asset acquired in business combination or from joint venture formation or both, that is not individually identified and separately recognized.

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