Revenues (Details) - USD ($) $ in Millions	3 Months Ended		9 Months Ended
	Sep. 28, 2019	Sep. 29, 2018	Sep. 28, 2019	Sep. 29, 2018
Revenues
Total revenues	$ 3,259	$ 3,200	$ 9,595	$ 10,222
United States
Revenues
Total revenues	2,128	1,864	6,178	6,179
Europe
Revenues
Total revenues	443	503	1,500	1,647
Asia and Australia
Revenues
Total revenues	278	376	720	1,050
Other international
Revenues
Total revenues	410	457	1,197	1,346
Commercial
Revenues
Total revenues	2,493	2,369	7,270	7,682
U.S. Government
Revenues
Total revenues	766	831	2,325	2,540
Textron Aviation
Revenues
Total revenues	1,201	1,133	3,458	3,419
Textron Aviation | United States
Revenues
Total revenues	836	740	2,361	2,319
Textron Aviation | Europe
Revenues
Total revenues	154	173	501	447
Textron Aviation | Asia and Australia
Revenues
Total revenues	80	70	168	215
Textron Aviation | Other international
Revenues
Total revenues	131	150	428	438
Textron Aviation | Commercial
Revenues
Total revenues	1,153	1,081	3,322	3,245
Textron Aviation | U.S. Government
Revenues
Total revenues	48	52	136	174
Textron Aviation | Aircraft
Revenues
Total revenues	797	756	2,296	2,267
Textron Aviation | Aftermarket parts and services
Revenues
Total revenues	404	377	1,162	1,152
Bell
Revenues
Total revenues	783	770	2,293	2,353
Bell | United States
Revenues
Total revenues	583	392	1,732	1,444
Bell | Europe
Revenues
Total revenues	41	54	108	131
Bell | Asia and Australia
Revenues
Total revenues	68	214	229	491
Bell | Other international
Revenues
Total revenues	91	110	224	287
Bell | Commercial
Revenues
Total revenues	306	258	815	801
Bell | U.S. Government
Revenues
Total revenues	477	512	1,478	1,552
Bell | Military aircraft and support programs
Revenues
Total revenues	473	505	1,463	1,525
Bell | Commercial helicopters, parts and services
Revenues
Total revenues	310	265	830	828
Textron Systems
Revenues
Total revenues	311	352	926	1,119
Textron Systems | United States
Revenues
Total revenues	247	293	753	877
Textron Systems | Europe
Revenues
Total revenues	11	14	51	49
Textron Systems | Asia and Australia
Revenues
Total revenues	37	10	66	66
Textron Systems | Other international
Revenues
Total revenues	16	35	56	127
Textron Systems | Commercial
Revenues
Total revenues	73	92	230	326
Textron Systems | U.S. Government
Revenues
Total revenues	238	260	696	793
Textron Systems | Unmanned systems
Revenues
Total revenues	147	154	416	485
Textron Systems | Marine and land systems
Revenues
Total revenues	47	87	155	248
Textron Systems | Simulation, training and other
Revenues
Total revenues	117	111	355	386
Industrial
Revenues
Total revenues	950	930	2,871	3,283
Industrial | United States
Revenues
Total revenues	454	435	1,309	1,521
Industrial | Europe
Revenues
Total revenues	236	261	838	1,016
Industrial | Asia and Australia
Revenues
Total revenues	93	81	254	273
Industrial | Other international
Revenues
Total revenues	167	153	470	473
Industrial | Commercial
Revenues
Total revenues	947	923	2,856	3,262
Industrial | U.S. Government
Revenues
Total revenues	3	7	15	21
Industrial | Fuel systems and functional components
Revenues
Total revenues	521	522	1,707	1,804
Industrial | Specialized vehicles
Revenues
Total revenues	429	408	1,164	1,231
Industrial | Tools and test equipment
Revenues
Total revenues				248
Finance
Revenues
Finance Revenue	14	15	47	48
Finance | United States
Revenues
Finance Revenue	8	4	23	18
Finance | Europe
Revenues
Finance Revenue	1	1	2	4
Finance | Asia and Australia
Revenues
Finance Revenue		1	3	5
Finance | Other international
Revenues
Finance Revenue	5	9	19	21
Finance | Commercial
Revenues
Finance Revenue	$ 14	$ 15	$ 47	$ 48