Goodwill and Intangible Assets - Goodwill (Details) - USD ($) $ in Millions	12 Months Ended
Jan. 02, 2021	Jan. 04, 2020
Disposal Group, Held-for-sale, Not Discontinued Operations
Changes in the carrying amount of goodwill
Goodwill classified as held for sale	$ 12
Manufacturing group
Changes in the carrying amount of goodwill
Beginning Balance	2,150	$ 2,218
Disposition		(71)
Acquisition	8	4
Reclassifications	(12)
Foreign currency translation	11	(1)
Ending Balance	2,157	2,150
Manufacturing group \| Textron Aviation
Changes in the carrying amount of goodwill
Beginning Balance	614	614
Disposition		0
Acquisition	4	0
Reclassifications	12
Foreign currency translation	1	0
Ending Balance	631	614
Manufacturing group \| Bell
Changes in the carrying amount of goodwill
Beginning Balance	31	31
Disposition		0
Acquisition	4	0
Reclassifications	0
Foreign currency translation	0	0
Ending Balance	35	31
Manufacturing group \| Textron Systems
Changes in the carrying amount of goodwill
Beginning Balance	1,033	1,100
Disposition		(71)
Acquisition	0	4
Reclassifications	(24)
Foreign currency translation	0	0
Ending Balance	1,009	1,033
Manufacturing group \| Industrial
Changes in the carrying amount of goodwill
Beginning Balance	472	473
Disposition		0
Acquisition	0	0
Reclassifications	0
Foreign currency translation	10	(1)
Ending Balance	$ 482	$ 472

Goodwill, Accounting Adjustments Related to Held-for-Sale Assets and Transfers

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- Definition

Amount classified as goodwill attributable to disposal group held for sale or disposed of.

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- Definition

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.

+ References

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Amount of increase in asset representing future economic benefits arising from other assets acquired in a business combination that are not individually identified and separately recognized resulting from a business combination.

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Amount of foreign currency translation gain (loss) which increases (decreases) an asset representing future economic benefits from other assets acquired in a business combination that are not individually identified and separately recognized.

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- Definition

A roll forward is a reconciliation of a concept from the beginning of a period to the end of a period.

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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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