Goodwill and Other Intangible Assets - Goodwill by Business Segment (Details)	3 Months Ended	9 Months Ended
Sep. 27, 2019 USD ($)	Oct. 02, 2020 USD ($) divestiture
Changes in the carrying amount of goodwill
Balance at January 3, 2020		$ 20,001,000,000
Goodwill decrease from divestitures		(541,000,000)
Impairment of goodwill	$ 0	(369,000,000)
Currency translation adjustments		(8,000,000)
Other (including adjustments to previously estimated fair value of assets acquired and liabilities assumed)		(91,000,000)
Balance at October 2, 2020		$ 18,992,000,000
Disposal Group, Disposed of by Sale, Not Discontinued Operations
Changes in the carrying amount of goodwill
Number of businesses divestitures \| divestiture		3
Disposal Group, Disposed of by Sale, Not Discontinued Operations \| Applied Kilovolts and Analytical Instrumentation, Airport Security and Automation and EOTech Businesses
Changes in the carrying amount of goodwill
Goodwill decrease from divestitures		$ (541,000,000)
Number of businesses divestitures \| divestiture		3
Integrated Mission Systems
Changes in the carrying amount of goodwill
Balance at January 3, 2020		$ 5,768,000,000
Goodwill decrease from divestitures		0
Impairment of goodwill		0
Currency translation adjustments		(3,000,000)
Other (including adjustments to previously estimated fair value of assets acquired and liabilities assumed)		740,000,000
Balance at October 2, 2020		6,505,000,000
Space and Airborne Systems
Changes in the carrying amount of goodwill
Balance at January 3, 2020		5,131,000,000
Goodwill decrease from divestitures		(2,000,000)
Impairment of goodwill		(5,000,000)
Currency translation adjustments		(4,000,000)
Other (including adjustments to previously estimated fair value of assets acquired and liabilities assumed)		112,000,000
Balance at October 2, 2020		5,232,000,000
Communication Systems
Changes in the carrying amount of goodwill
Balance at January 3, 2020		4,243,000,000
Goodwill decrease from divestitures		(9,000,000)
Impairment of goodwill		0
Currency translation adjustments		(2,000,000)
Other (including adjustments to previously estimated fair value of assets acquired and liabilities assumed)		(82,000,000)
Balance at October 2, 2020		4,150,000,000
Aviation Systems
Changes in the carrying amount of goodwill
Balance at January 3, 2020		4,859,000,000
Goodwill decrease from divestitures		(530,000,000)
Impairment of goodwill		(364,000,000)
Currency translation adjustments		1,000,000
Other (including adjustments to previously estimated fair value of assets acquired and liabilities assumed)		(861,000,000)
Balance at October 2, 2020		$ 3,105,000,000

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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 loss from the write-down 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 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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