INFORMATION ON BUSINESS SEGMENTS - Income Statement Information For Each Segment (Details) - USD ($) $ in Millions	3 Months Ended
	Mar. 28, 2021	Mar. 29, 2020
Net sales
Net sales	$ 16,258	$ 15,651
Aeronautics
Net sales
Net sales	6,387	6,369
MFC
Net sales
Net sales	2,749	2,619
RMS
Net sales
Net sales	4,107	3,746
Space
Net sales
Net sales	3,015	2,917
United States
Net sales
Net sales	11,779	11,395
United States | Aeronautics
Net sales
Net sales	4,288	4,048
United States | MFC
Net sales
Net sales	2,046	1,959
United States | RMS
Net sales
Net sales	2,887	2,891
United States | Space
Net sales
Net sales	2,558	2,497
Asia Pacific
Net sales
Net sales	1,596	1,416
Asia Pacific | Aeronautics
Net sales
Net sales	893	995
Asia Pacific | MFC
Net sales
Net sales	51	75
Asia Pacific | RMS
Net sales
Net sales	650	318
Asia Pacific | Space
Net sales
Net sales	2	28
Europe
Net sales
Net sales	1,692	1,681
Europe | Aeronautics
Net sales
Net sales	854	948
Europe | MFC
Net sales
Net sales	182	168
Europe | RMS
Net sales
Net sales	201	167
Europe | Space
Net sales
Net sales	455	398
Middle East
Net sales
Net sales	912	936
Middle East | Aeronautics
Net sales
Net sales	284	328
Middle East | MFC
Net sales
Net sales	458	407
Middle East | RMS
Net sales
Net sales	170	207
Middle East | Space
Net sales
Net sales	0	(6)
Other
Net sales
Net sales	279	223
Other | Aeronautics
Net sales
Net sales	68	50
Other | MFC
Net sales
Net sales	12	10
Other | RMS
Net sales
Net sales	199	163
Other | Space
Net sales
Net sales	0	0
U.S. Government
Net sales
Net sales	11,675	11,259
U.S. Government | Aeronautics
Net sales
Net sales	4,273	4,033
U.S. Government | MFC
Net sales
Net sales	2,041	1,955
U.S. Government | RMS
Net sales
Net sales	2,810	2,788
U.S. Government | Space
Net sales
Net sales	2,551	2,483
International
Net sales
Net sales	4,479	4,256
International | Aeronautics
Net sales
Net sales	2,099	2,321
International | MFC
Net sales
Net sales	703	660
International | RMS
Net sales
Net sales	1,220	855
International | Space
Net sales
Net sales	457	420
U.S. commercial and other
Net sales
Net sales	104	136
U.S. commercial and other | Aeronautics
Net sales
Net sales	15	15
U.S. commercial and other | MFC
Net sales
Net sales	5	4
U.S. commercial and other | RMS
Net sales
Net sales	77	103
U.S. commercial and other | Space
Net sales
Net sales	7	14
Fixed-price
Net sales
Net sales	9,903	9,303
Fixed-price | Aeronautics
Net sales
Net sales	4,734	4,584
Fixed-price | MFC
Net sales
Net sales	1,878	1,718
Fixed-price | RMS
Net sales
Net sales	2,677	2,482
Fixed-price | Space
Net sales
Net sales	614	519
Cost-reimbursable
Net sales
Net sales	6,355	6,348
Cost-reimbursable | Aeronautics
Net sales
Net sales	1,653	1,785
Cost-reimbursable | MFC
Net sales
Net sales	871	901
Cost-reimbursable | RMS
Net sales
Net sales	1,430	1,264
Cost-reimbursable | Space
Net sales
Net sales	2,401	2,398
Products
Net sales
Net sales	13,753	13,166
Products | Aeronautics
Net sales
Net sales	5,479	5,455
Products | MFC
Net sales
Net sales	2,410	2,275
Products | RMS
Net sales
Net sales	3,300	2,986
Products | Space
Net sales
Net sales	2,564	2,450
Services
Net sales
Net sales	2,505	2,485
Services | Aeronautics
Net sales
Net sales	908	914
Services | MFC
Net sales
Net sales	339	344
Services | RMS
Net sales
Net sales	807	760
Services | Space
Net sales
Net sales	$ 451	$ 467