INFORMATION ON BUSINESS SEGMENTS - Income Statement Information For Each Segment (Details) - USD ($) $ in Millions	3 Months Ended		9 Months Ended
	Sep. 27, 2020	Sep. 29, 2019	Sep. 27, 2020	Sep. 29, 2019
Net sales
Net sales	$ 16,495	$ 15,171	$ 48,366	$ 43,934
Aeronautics
Net sales
Net sales	6,680	6,178	19,552	17,312
MFC
Net sales
Net sales	2,971	2,601	8,391	7,362
RMS
Net sales
Net sales	3,998	3,709	11,783	11,239
Space
Net sales
Net sales	2,846	2,683	8,640	8,021
United States
Net sales
Net sales	11,707	10,821	36,150	31,610
United States | Aeronautics
Net sales
Net sales	3,951	3,547	13,370	10,576
United States | MFC
Net sales
Net sales	2,207	2,029	6,268	5,645
United States | RMS
Net sales
Net sales	3,084	2,905	9,003	8,466
United States | Space
Net sales
Net sales	2,465	2,340	7,509	6,923
Asia Pacific
Net sales
Net sales	1,573	1,487	3,894	4,164
Asia Pacific | Aeronautics
Net sales
Net sales	1,099	1,046	2,447	2,736
Asia Pacific | MFC
Net sales
Net sales	70	107	217	315
Asia Pacific | RMS
Net sales
Net sales	383	317	1,165	1,065
Asia Pacific | Space
Net sales
Net sales	21	17	65	48
Europe
Net sales
Net sales	1,900	1,738	4,741	4,658
Europe | Aeronautics
Net sales
Net sales	1,141	1,106	2,595	2,751
Europe | MFC
Net sales
Net sales	208	138	546	363
Europe | RMS
Net sales
Net sales	191	168	528	509
Europe | Space
Net sales
Net sales	360	326	1,072	1,035
Middle East
Net sales
Net sales	1,121	979	2,925	2,883
Middle East | Aeronautics
Net sales
Net sales	440	455	981	1,127
Middle East | MFC
Net sales
Net sales	475	318	1,324	1,003
Middle East | RMS
Net sales
Net sales	206	206	626	738
Middle East | Space
Net sales
Net sales	0	0	(6)	15
Other
Net sales
Net sales	194	146	656	619
Other | Aeronautics
Net sales
Net sales	49	24	159	122
Other | MFC
Net sales
Net sales	11	9	36	36
Other | RMS
Net sales
Net sales	134	113	461	461
Other | Space
Net sales
Net sales	0	0	0	0
U.S. Government
Net sales
Net sales	11,570	10,599	35,738	30,961
U.S. Government | Aeronautics
Net sales
Net sales	3,930	3,509	13,315	10,420
U.S. Government | MFC
Net sales
Net sales	2,206	1,995	6,259	5,528
U.S. Government | RMS
Net sales
Net sales	2,971	2,763	8,685	8,113
U.S. Government | Space
Net sales
Net sales	2,463	2,332	7,479	6,900
International
Net sales
Net sales	4,788	4,350	12,216	12,324
International | Aeronautics
Net sales
Net sales	2,729	2,631	6,182	6,736
International | MFC
Net sales
Net sales	764	572	2,123	1,717
International | RMS
Net sales
Net sales	914	804	2,780	2,773
International | Space
Net sales
Net sales	381	343	1,131	1,098
U.S. commercial and other
Net sales
Net sales	137	222	412	649
U.S. commercial and other | Aeronautics
Net sales
Net sales	21	38	55	156
U.S. commercial and other | MFC
Net sales
Net sales	1	34	9	117
U.S. commercial and other | RMS
Net sales
Net sales	113	142	318	353
U.S. commercial and other | Space
Net sales
Net sales	2	8	30	23
Fixed-price
Net sales
Net sales	9,934	9,311	28,703	26,703
Fixed-price | Aeronautics
Net sales
Net sales	4,718	4,567	13,769	12,777
Fixed-price | MFC
Net sales
Net sales	2,034	1,681	5,629	4,660
Fixed-price | RMS
Net sales
Net sales	2,666	2,536	7,787	7,681
Fixed-price | Space
Net sales
Net sales	516	527	1,518	1,585
Cost-reimbursable
Net sales
Net sales	6,561	5,860	19,663	17,231
Cost-reimbursable | Aeronautics
Net sales
Net sales	1,962	1,611	5,783	4,535
Cost-reimbursable | MFC
Net sales
Net sales	937	920	2,762	2,702
Cost-reimbursable | RMS
Net sales
Net sales	1,332	1,173	3,996	3,558
Cost-reimbursable | Space
Net sales
Net sales	2,330	2,156	7,122	6,436
Products
Net sales
Net sales	13,869	12,728	40,607	36,701
Products | Aeronautics
Net sales
Net sales	5,742	5,340	16,671	14,876
Products | MFC
Net sales
Net sales	2,614	2,172	7,311	6,051
Products | RMS
Net sales
Net sales	3,120	2,982	9,365	9,064
Products | Space
Net sales
Net sales	2,393	2,234	7,260	6,710
Services
Net sales
Net sales	2,626	2,443	7,759	7,233
Services | Aeronautics
Net sales
Net sales	938	838	2,881	2,436
Services | MFC
Net sales
Net sales	357	429	1,080	1,311
Services | RMS
Net sales
Net sales	878	727	2,418	2,175
Services | Space
Net sales
Net sales	$ 453	$ 449	$ 1,380	$ 1,311