Revenues - Disaggregation of Revenue (Details) - USD ($) $ in Millions	3 Months Ended		9 Months Ended
	Oct. 02, 2021	Oct. 03, 2020	Oct. 02, 2021	Oct. 03, 2020
Revenues
Revenues	$ 2,990	$ 2,735	$ 9,060	$ 7,984
United States
Revenues
Revenues	2,134	1,841	6,305	5,519
Europe
Revenues
Revenues	315	321	1,052	899
Asia and Australia
Revenues
Revenues	253	242	808	696
Other international
Revenues
Revenues	288	331	895	870
Commercial
Revenues
Revenues	2,230	1,928	6,578	5,361
U.S. Government
Revenues
Revenues	760	807	2,482	2,623
Textron Aviation
Revenues
Revenues	1,181	795	3,207	2,414
Textron Aviation | United States
Revenues
Revenues	915	562	2,409	1,677
Textron Aviation | Europe
Revenues
Revenues	97	65	303	219
Textron Aviation | Asia and Australia
Revenues
Revenues	58	68	209	241
Textron Aviation | Other international
Revenues
Revenues	111	100	286	277
Textron Aviation | Commercial
Revenues
Revenues	1,149	758	3,122	2,322
Textron Aviation | U.S. Government
Revenues
Revenues	32	37	85	92
Textron Aviation | Aircraft
Revenues
Revenues	814	486	2,146	1,479
Textron Aviation | Aftermarket parts and services
Revenues
Revenues	367	309	1,061	935
Bell
Revenues
Revenues	769	793	2,506	2,438
Bell | United States
Revenues
Revenues	569	608	1,862	1,979
Bell | Europe
Revenues
Revenues	48	43	131	88
Bell | Asia and Australia
Revenues
Revenues	90	67	276	183
Bell | Other international
Revenues
Revenues	62	75	237	188
Bell | Commercial
Revenues
Revenues	278	273	894	687
Bell | U.S. Government
Revenues
Revenues	491	520	1,612	1,751
Bell | Military aircraft and support programs
Revenues
Revenues	488	515	1,637	1,737
Bell | Commercial helicopters, parts and services
Revenues
Revenues	281	278	869	701
Textron Systems
Revenues
Revenues	299	302	960	956
Textron Systems | United States
Revenues
Revenues	266	263	852	825
Textron Systems | Europe
Revenues
Revenues	10	10	29	33
Textron Systems | Asia and Australia
Revenues
Revenues	16	15	52	50
Textron Systems | Other international
Revenues
Revenues	7	14	27	48
Textron Systems | Commercial
Revenues
Revenues	62	54	187	182
Textron Systems | U.S. Government
Revenues
Revenues	237	248	773	774
Textron Systems | Air systems
Revenues
Revenues	99	138	339	423
Textron Systems | Land and sea systems
Revenues
Revenues	53	54	174	177
Textron Systems | Other
Revenues
Revenues	147	110	447	356
Industrial
Revenues
Revenues	730	832	2,349	2,134
Industrial | United States
Revenues
Revenues	377	401	1,161	1,017
Industrial | Europe
Revenues
Revenues	160	203	588	558
Industrial | Asia and Australia
Revenues
Revenues	88	92	267	221
Industrial | Other international
Revenues
Revenues	105	136	333	338
Industrial | Commercial
Revenues
Revenues	730	830	2,337	2,128
Industrial | U.S. Government
Revenues
Revenues	0	2	12	6
Industrial | Fuel systems and functional components
Revenues
Revenues	382	497	1,319	1,233
Industrial | Specialized vehicles
Revenues
Revenues	348	335	1,030	901
Finance
Revenues
Revenues	11	13	38	42
Finance | United States
Revenues
Revenues	7	7	21	21
Finance | Europe
Revenues
Revenues	0	0	1	1
Finance | Asia and Australia
Revenues
Revenues	1	0	4	1
Finance | Other international
Revenues
Revenues	3	6	12	19
Finance | Commercial
Revenues
Revenues	11	13	38	42
Finance | U.S. Government
Revenues
Revenues	$ 0	$ 0	$ 0	$ 0