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Amount classified as intangible assets, excluding goodwill, attributable to disposal group held for sale or disposed of.

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Accumulated amount of amortization of assets, excluding financial assets and goodwill, lacking physical substance with a finite life.

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Amount before amortization of assets, excluding financial assets and goodwill, lacking physical substance with a finite life.

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Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table.

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Amount after amortization of assets, excluding financial assets and goodwill, lacking physical substance with a finite life.

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Amount of gain (loss) from sale and disposal of integrated set of activities and assets capable of being conducted and managed for purpose of providing return in form of dividend, lower cost, or other economic benefit to investor, owner, member and participant.

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Amount before accumulated amortization of intangible assets, excluding goodwill.

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Sum of the carrying amounts of all intangible assets, excluding goodwill, as of the balance sheet date, net of accumulated amortization and impairment charges.

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Goodwill and Other Intangible Assets - Intangibles Assets (Details) $ in Millions	3 Months Ended		9 Months Ended
	Oct. 02, 2020 USD ($)	Sep. 27, 2019 USD ($)	Oct. 02, 2020 USD ($) divestiture	Sep. 27, 2019 USD ($)	Jan. 03, 2020 USD ($)
Finite-Lived Intangible Assets [Line Items]
Gross Carrying Amount	$ 7,754		$ 7,754		$ 7,461
Accumulated Amortization	1,406		1,406		875
Net Carrying Amount	6,348		6,348		6,586
Total intangibles assets, Gross Carrying Amount	9,578		9,578		9,333
Total identifiable intangible assets	8,172		8,172		8,458
Intangible assets derecognized as part of the gain on sale of businesses	10	$ (229)	$ 62	$ (229)
Disposal Group, Disposed of by Sale, Not Discontinued Operations
Finite-Lived Intangible Assets [Line Items]
Number of businesses divestitures \| divestiture			3
Intangible assets derecognized as part of the gain on sale of businesses			$ 296
Disposal Group, Held-for-sale, Not Discontinued Operations
Finite-Lived Intangible Assets [Line Items]
Intangibles reclassified as assets of disposal group held for sale	5		5
In-process research and development
Finite-Lived Intangible Assets [Line Items]
Indefinite-lived Intangibles	21		21		69
L3 trade name
Finite-Lived Intangible Assets [Line Items]
Indefinite-lived Intangibles	1,803		1,803		1,803
Customer relationships
Finite-Lived Intangible Assets [Line Items]
Gross Carrying Amount	6,923		6,923		6,518
Accumulated Amortization	1,103		1,103		653
Net Carrying Amount	5,820		5,820		5,865
Developed technologies
Finite-Lived Intangible Assets [Line Items]
Gross Carrying Amount	670		670		768
Accumulated Amortization	242		242		183
Net Carrying Amount	428		428		585
Contract backlog
Finite-Lived Intangible Assets [Line Items]
Gross Carrying Amount	19		19		0
Accumulated Amortization	15		15		0
Net Carrying Amount	4		4		0
L3 trade name
Finite-Lived Intangible Assets [Line Items]
Gross Carrying Amount	138		138		165
Accumulated Amortization	43		43		35
Net Carrying Amount	95		95		130
Other
Finite-Lived Intangible Assets [Line Items]
Gross Carrying Amount	4		4		10
Accumulated Amortization	3		3		4
Net Carrying Amount	$ 1		$ 1		$ 6