Revenues (Details) - USD ($) $ in Millions	3 Months Ended		6 Months Ended
	Jul. 04, 2020	Jun. 29, 2019	Jul. 04, 2020	Jun. 29, 2019
Revenues
Total revenues	$ 2,472	$ 3,227	$ 5,249	$ 6,336
United States
Revenues
Total revenues	1,770	2,029	3,678	4,050
Europe
Revenues
Total revenues	229	519	578	1,057
Asia and Australia
Revenues
Total revenues	207	243	454	442
Other international
Revenues
Total revenues	266	436	539	787
Commercial
Revenues
Total revenues	1,563	2,459	3,433	4,777
U.S. Government
Revenues
Total revenues	909	768	1,816	1,559
Textron Aviation
Revenues
Total revenues	747	1,123	1,619	2,257
Textron Aviation | United States
Revenues
Total revenues	518	736	1,115	1,525
Textron Aviation | Europe
Revenues
Total revenues	70	164	154	347
Textron Aviation | Asia and Australia
Revenues
Total revenues	50	65	173	88
Textron Aviation | Other international
Revenues
Total revenues	109	158	177	297
Textron Aviation | Commercial
Revenues
Total revenues	716	1,077	1,564	2,169
Textron Aviation | U.S. Government
Revenues
Total revenues	31	46	55	88
Textron Aviation | Aircraft
Revenues
Total revenues	478	733	993	1,499
Textron Aviation | Aftermarket parts and services
Revenues
Total revenues	269	390	626	758
Bell
Revenues
Total revenues	822	771	1,645	1,510
Bell | United States
Revenues
Total revenues	681	571	1,371	1,149
Bell | Europe
Revenues
Total revenues	21	47	45	67
Bell | Asia and Australia
Revenues
Total revenues	66	79	116	161
Bell | Other international
Revenues
Total revenues	54	74	113	133
Bell | Commercial
Revenues
Total revenues	216	279	414	509
Bell | U.S. Government
Revenues
Total revenues	606	492	1,231	1,001
Bell | Military aircraft and support programs
Revenues
Total revenues	602	482	1,222	990
Bell | Commercial helicopters, parts and services
Revenues
Total revenues	220	289	423	520
Textron Systems
Revenues
Total revenues	326	308	654	615
Textron Systems | United States
Revenues
Total revenues	276	249	562	506
Textron Systems | Europe
Revenues
Total revenues	11	17	23	40
Textron Systems | Asia and Australia
Revenues
Total revenues	15	13	35	29
Textron Systems | Other international
Revenues
Total revenues	24	29	34	40
Textron Systems | Commercial
Revenues
Total revenues	57	83	128	157
Textron Systems | U.S. Government
Revenues
Total revenues	269	225	526	458
Textron Systems | Unmanned systems
Revenues
Total revenues	169	135	317	269
Textron Systems | Marine and land systems
Revenues
Total revenues	43	60	91	108
Textron Systems | Simulation, training and other
Revenues
Total revenues	114	113	246	238
Industrial
Revenues
Total revenues	562	1,009	1,302	1,921
Industrial | United States
Revenues
Total revenues	287	466	616	855
Industrial | Europe
Revenues
Total revenues	127	291	355	602
Industrial | Asia and Australia
Revenues
Total revenues	76	84	129	161
Industrial | Other international
Revenues
Total revenues	72	168	202	303
Industrial | Commercial
Revenues
Total revenues	559	1,004	1,298	1,909
Industrial | U.S. Government
Revenues
Total revenues	3	5	4	12
Industrial | Fuel systems and functional components
Revenues
Total revenues	271	592	736	1,186
Industrial | Specialized vehicles
Revenues
Total revenues	291	417	566	735
Finance
Revenues
Finance revenues	15	16	29	33
Finance | United States
Revenues
Finance revenues	8	7	14	15
Finance | Europe
Revenues
Finance revenues			1	1
Finance | Asia and Australia
Revenues
Finance revenues		2	1	3
Finance | Other international
Revenues
Finance revenues	7	7	13	14
Finance | Commercial
Revenues
Finance revenues	$ 15	$ 16	$ 29	$ 33