Revenues (Details) - USD ($) $ in Millions	3 Months Ended		9 Months Ended
	Oct. 03, 2020	Sep. 28, 2019	Oct. 03, 2020	Sep. 28, 2019
Revenues
Revenues	$ 2,735	$ 3,259	$ 7,984	$ 9,595
United States
Revenues
Revenues	1,841	2,128	5,519	6,178
Europe
Revenues
Revenues	321	443	899	1,500
Asia and Australia
Revenues
Revenues	242	278	696	720
Other international
Revenues
Revenues	331	410	870	1,197
Commercial
Revenues
Revenues	1,928	2,493	5,361	7,270
U.S. Government
Revenues
Revenues	807	766	2,623	2,325
Textron Aviation
Revenues
Revenues	795	1,201	2,414	3,458
Textron Aviation | United States
Revenues
Revenues	562	836	1,677	2,361
Textron Aviation | Europe
Revenues
Revenues	65	154	219	501
Textron Aviation | Asia and Australia
Revenues
Revenues	68	80	241	168
Textron Aviation | Other international
Revenues
Revenues	100	131	277	428
Textron Aviation | Commercial
Revenues
Revenues	758	1,153	2,322	3,322
Textron Aviation | U.S. Government
Revenues
Revenues	37	48	92	136
Textron Aviation | Aircraft
Revenues
Revenues	486	797	1,479	2,296
Textron Aviation | Aftermarket parts and services
Revenues
Revenues	309	404	935	1,162
Bell
Revenues
Revenues	793	783	2,438	2,293
Bell | United States
Revenues
Revenues	608	583	1,979	1,732
Bell | Europe
Revenues
Revenues	43	41	88	108
Bell | Asia and Australia
Revenues
Revenues	67	68	183	229
Bell | Other international
Revenues
Revenues	75	91	188	224
Bell | Commercial
Revenues
Revenues	273	306	687	815
Bell | U.S. Government
Revenues
Revenues	520	477	1,751	1,478
Bell | Military aircraft and support programs
Revenues
Revenues	515	473	1,737	1,463
Bell | Commercial helicopters, parts and services
Revenues
Revenues	278	310	701	830
Textron Systems
Revenues
Revenues	302	311	956	926
Textron Systems | United States
Revenues
Revenues	263	247	825	753
Textron Systems | Europe
Revenues
Revenues	10	11	33	51
Textron Systems | Asia and Australia
Revenues
Revenues	15	37	50	66
Textron Systems | Other international
Revenues
Revenues	14	16	48	56
Textron Systems | Commercial
Revenues
Revenues	54	73	182	230
Textron Systems | U.S. Government
Revenues
Revenues	248	238	774	696
Textron Systems | Unmanned systems
Revenues
Revenues	156	147	473	416
Textron Systems | Marine and land systems
Revenues
Revenues	36	47	127	155
Textron Systems | Simulation, training and other
Revenues
Revenues	110	117	356	355
Industrial
Revenues
Revenues	832	950	2,134	2,871
Industrial | United States
Revenues
Revenues	401	454	1,017	1,309
Industrial | Europe
Revenues
Revenues	203	236	558	838
Industrial | Asia and Australia
Revenues
Revenues	92	93	221	254
Industrial | Other international
Revenues
Revenues	136	167	338	470
Industrial | Commercial
Revenues
Revenues	830	947	2,128	2,856
Industrial | U.S. Government
Revenues
Revenues	2	3	6	15
Industrial | Fuel systems and functional components
Revenues
Revenues	497	521	1,233	1,707
Industrial | Specialized vehicles
Revenues
Revenues	335	429	901	1,164
Finance
Revenues
Revenues	13	14	42	47
Finance | United States
Revenues
Revenues	7	8	21	23
Finance | Europe
Revenues
Revenues	0	1	1	2
Finance | Asia and Australia
Revenues
Revenues	0	0	1	3
Finance | Other international
Revenues
Revenues	6	5	19	19
Finance | Commercial
Revenues
Revenues	13	14	42	47
Finance | U.S. Government
Revenues
Revenues	$ 0	$ 0	$ 0	$ 0