Goodwill and Other Intangible Assets - Goodwill by Business Segment (Details) - USD ($) $ in Millions	6 Months Ended	12 Months Ended
Jul. 02, 2021	Jul. 03, 2020	Jan. 01, 2021
Changes in the carrying amount of goodwill
Beginning Balance	$ 18,876	$ 20,001	$ 20,001
Goodwill decrease from divestitures	(538)	(533)
Decrease from reclassification to assets of disposal group held for sale	(26)	(9)
Impairment of goodwill	62	369
Currency translation adjustments	(16)	(11)
Other (including adjustments to previously estimated fair value of assets acquired and liabilities assumed)		(64)
Ending Balance	18,234	19,015	18,876
Disposed of by Sale \| CPS and Military Training Businesses
Changes in the carrying amount of goodwill
Goodwill decrease from divestitures	(538)
Disposed of by Sale \| Applied Kilovolts and Analytical Instrumentation business
Changes in the carrying amount of goodwill
Goodwill decrease from divestitures		(533)
Held-for-sale
Changes in the carrying amount of goodwill
Decrease from reclassification to assets of disposal group held for sale	(26)	(9)
Integrated Mission Systems
Changes in the carrying amount of goodwill
Beginning Balance	6,499	5,768	5,768
Goodwill decrease from divestitures	0	0
Decrease from reclassification to assets of disposal group held for sale	0	0
Impairment of goodwill	0	0
Currency translation adjustments	1	3
Other (including adjustments to previously estimated fair value of assets acquired and liabilities assumed)		740
Ending Balance	6,500	6,511	6,499
Space and Airborne Systems
Changes in the carrying amount of goodwill
Beginning Balance	5,232	5,131	5,131
Goodwill decrease from divestitures	0	(2)
Decrease from reclassification to assets of disposal group held for sale	0	0
Impairment of goodwill	0	5
Currency translation adjustments	(13)	(7)
Other (including adjustments to previously estimated fair value of assets acquired and liabilities assumed)		124
Ending Balance	5,219	5,241	5,232
Communication Systems
Changes in the carrying amount of goodwill
Beginning Balance	4,153	4,243	4,243
Goodwill decrease from divestitures	0	0
Decrease from reclassification to assets of disposal group held for sale	0	(9)
Impairment of goodwill	0	0
Currency translation adjustments	1	(2)
Other (including adjustments to previously estimated fair value of assets acquired and liabilities assumed)		(81)
Ending Balance	4,154	4,151	4,153
Aviation Systems
Changes in the carrying amount of goodwill
Beginning Balance	2,992	4,859	4,859
Goodwill decrease from divestitures	(538)	(531)
Decrease from reclassification to assets of disposal group held for sale	(26)	0
Impairment of goodwill	62	364
Currency translation adjustments	(5)	(5)
Other (including adjustments to previously estimated fair value of assets acquired and liabilities assumed)		(847)
Ending Balance	$ 2,361	$ 3,112	$ 2,992

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.

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