Goodwill and Other Intangible Assets - Goodwill by Business Segment (Details) - USD ($)	3 Months Ended	6 Months Ended
Sep. 27, 2019	Jul. 03, 2020
Changes in the carrying amount of goodwill
Balance at January 3, 2020		$ 20,001,000,000
Goodwill decrease from divestitures		(533,000,000)
Decrease from reclassification to assets of disposal group held for sale		(9,000,000)
Impairment of goodwill	$ 0	(369,000,000)
Currency translation adjustments		(11,000,000)
Other (including adjustments to previously estimated fair value of assets acquired and liabilities assumed)		(64,000,000)
Balance at July 3, 2020		19,015,000,000
Disposal Group, Disposed of by Sale, Not Discontinued Operations \| Applied Kilovolts and Analytical Instrumentation Business
Changes in the carrying amount of goodwill
Goodwill decrease from divestitures		(533,000,000)
Integrated Mission Systems
Changes in the carrying amount of goodwill
Balance at January 3, 2020		5,768,000,000
Goodwill decrease from divestitures		0
Decrease from reclassification to assets of disposal group held for sale		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 July 3, 2020		6,511,000,000
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)
Decrease from reclassification to assets of disposal group held for sale		0
Impairment of goodwill		(5,000,000)
Currency translation adjustments		(7,000,000)
Other (including adjustments to previously estimated fair value of assets acquired and liabilities assumed)		124,000,000
Balance at July 3, 2020		5,241,000,000
Communication Systems
Changes in the carrying amount of goodwill
Balance at January 3, 2020		4,243,000,000
Goodwill decrease from divestitures		0
Decrease from reclassification to assets of disposal group held for sale		(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)		(81,000,000)
Balance at July 3, 2020		4,151,000,000
Communication Systems \| Disposal Group, Held-for-sale, Not Discontinued Operations \| EOTech Business
Changes in the carrying amount of goodwill
Decrease from reclassification to assets of disposal group held for sale		(9,000,000)
Aviation Systems
Changes in the carrying amount of goodwill
Balance at January 3, 2020		4,859,000,000
Goodwill decrease from divestitures		(531,000,000)
Decrease from reclassification to assets of disposal group held for sale		0
Impairment of goodwill		(364,000,000)
Currency translation adjustments		(5,000,000)
Other (including adjustments to previously estimated fair value of assets acquired and liabilities assumed)		(847,000,000)
Balance at July 3, 2020		$ 3,112,000,000

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 divestiture 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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