Goodwill and Other Intangible Assets - Goodwill by Business Segment (Details)	3 Months Ended
Apr. 03, 2020 USD ($) divestiture	Sep. 27, 2019 USD ($)
Changes in the carrying amount of goodwill
Balance at January 3, 2020	$ 20,001,000,000
Decrease from reclassification to assets of disposal group held for sale	(599,000,000)
Impairment of goodwill	(301,000,000)	$ 0
Currency translation adjustments	(24,000,000)
Other (including adjustments to previously estimated fair value of assets acquired and liabilities assumed)	188,000,000
Balance at April 3, 2020	$ 19,265,000,000
Number of pending divestitures \| divestiture	3
Discontinued Operations, Held-for-sale
Changes in the carrying amount of goodwill
Decrease from reclassification to assets of disposal group held for sale	$ (599,000,000)
Integrated Mission Systems
Changes in the carrying amount of goodwill
Balance at January 3, 2020	5,768,000,000
Decrease from reclassification to assets of disposal group held for sale	0
Impairment of goodwill	0
Currency translation adjustments	(2,000,000)
Other (including adjustments to previously estimated fair value of assets acquired and liabilities assumed)	22,000,000
Balance at April 3, 2020	5,788,000,000
Space and Airborne Systems
Changes in the carrying amount of goodwill
Balance at January 3, 2020	5,131,000,000
Decrease from reclassification to assets of disposal group held for sale	(2,000,000)
Impairment of goodwill	(5,000,000)
Currency translation adjustments	(9,000,000)
Other (including adjustments to previously estimated fair value of assets acquired and liabilities assumed)	55,000,000
Balance at April 3, 2020	5,170,000,000
Communication Systems
Changes in the carrying amount of goodwill
Balance at January 3, 2020	4,243,000,000
Decrease from reclassification to assets of disposal group held for sale	(9,000,000)
Impairment of goodwill	0
Currency translation adjustments	(3,000,000)
Other (including adjustments to previously estimated fair value of assets acquired and liabilities assumed)	38,000,000
Balance at April 3, 2020	4,269,000,000
Aviation Systems
Changes in the carrying amount of goodwill
Balance at January 3, 2020	4,859,000,000
Decrease from reclassification to assets of disposal group held for sale	(588,000,000)
Impairment of goodwill	(296,000,000)
Currency translation adjustments	(10,000,000)
Other (including adjustments to previously estimated fair value of assets acquired and liabilities assumed)	73,000,000
Balance at April 3, 2020	$ 4,038,000,000

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

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Amount of transfers into (out of) an asset representing the future economic benefits arising from other assets acquired in a business combination that are not individually identified and separately recognized.

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