Information on Business Segments - Income Statement Information For Each Segment (Details) - USD ($) $ in Millions	3 Months Ended								12 Months Ended
	Dec. 31, 2020	Sep. 27, 2020	Jun. 28, 2020	Mar. 29, 2020	Dec. 31, 2019	Sep. 29, 2019	Jun. 30, 2019	Mar. 31, 2019	Dec. 31, 2020	Dec. 31, 2019	Dec. 31, 2018
Segment Reporting Information [Line Items]
Net sales	$ 17,032	$ 16,495	$ 16,220	$ 15,651	$ 15,878	$ 15,171	$ 14,427	$ 14,336	$ 65,398	$ 59,812	$ 53,762
Aeronautics
Segment Reporting Information [Line Items]
Net sales									26,266	23,693	21,242
MFC
Segment Reporting Information [Line Items]
Net sales									11,257	10,131	8,462
RMS
Segment Reporting Information [Line Items]
Net sales									15,995	15,128	14,250
Space
Segment Reporting Information [Line Items]
Net sales									11,880	10,860	9,808
United States
Segment Reporting Information [Line Items]
Net sales									49,012	43,281	38,606
United States | Aeronautics
Segment Reporting Information [Line Items]
Net sales									18,254	14,960	13,507
United States | MFC
Segment Reporting Information [Line Items]
Net sales									8,415	7,666	6,272
United States | RMS
Segment Reporting Information [Line Items]
Net sales									12,009	11,306	10,557
United States | Space
Segment Reporting Information [Line Items]
Net sales									10,334	9,349	8,270
Asia Pacific
Segment Reporting Information [Line Items]
Net sales									5,176	5,826	5,280
Asia Pacific | Aeronautics
Segment Reporting Information [Line Items]
Net sales									3,162	3,882	3,335
Asia Pacific | MFC
Segment Reporting Information [Line Items]
Net sales									280	420	427
Asia Pacific | RMS
Segment Reporting Information [Line Items]
Net sales									1,666	1,451	1,433
Asia Pacific | Space
Segment Reporting Information [Line Items]
Net sales									68	73	85
Europe
Segment Reporting Information [Line Items]
Net sales									6,334	5,928	5,403
Europe | Aeronautics
Segment Reporting Information [Line Items]
Net sales									3,283	3,224	2,837
Europe | MFC
Segment Reporting Information [Line Items]
Net sales									767	516	321
Europe | RMS
Segment Reporting Information [Line Items]
Net sales									806	769	829
Europe | Space
Segment Reporting Information [Line Items]
Net sales									1,478	1,419	1,416
Middle East
Segment Reporting Information [Line Items]
Net sales									3,940	3,944	3,602
Middle East | Aeronautics
Segment Reporting Information [Line Items]
Net sales									1,344	1,465	1,380
Middle East | MFC
Segment Reporting Information [Line Items]
Net sales									1,749	1,481	1,404
Middle East | RMS
Segment Reporting Information [Line Items]
Net sales									847	979	781
Middle East | Space
Segment Reporting Information [Line Items]
Net sales									0	19	37
Other
Segment Reporting Information [Line Items]
Net sales									936	833	871
Other | Aeronautics
Segment Reporting Information [Line Items]
Net sales									223	162	183
Other | MFC
Segment Reporting Information [Line Items]
Net sales									46	48	38
Other | RMS
Segment Reporting Information [Line Items]
Net sales									667	623	650
Other | Space
Segment Reporting Information [Line Items]
Net sales									0	0	0
U.S. Government
Segment Reporting Information [Line Items]
Net sales									48,468	42,425	37,716
U.S. Government | Aeronautics
Segment Reporting Information [Line Items]
Net sales									18,175	14,776	13,321
U.S. Government | MFC
Segment Reporting Information [Line Items]
Net sales									8,404	7,524	6,088
U.S. Government | RMS
Segment Reporting Information [Line Items]
Net sales									11,596	10,803	10,083
U.S. Government | Space
Segment Reporting Information [Line Items]
Net sales									10,293	9,322	8,224
International
Segment Reporting Information [Line Items]
Net sales									16,386	16,531	15,156
International | Aeronautics
Segment Reporting Information [Line Items]
Net sales									8,012	8,733	7,735
International | MFC
Segment Reporting Information [Line Items]
Net sales									2,842	2,465	2,190
International | RMS
Segment Reporting Information [Line Items]
Net sales									3,986	3,822	3,693
International | Space
Segment Reporting Information [Line Items]
Net sales									1,546	1,511	1,538
U.S. commercial and other
Segment Reporting Information [Line Items]
Net sales									544	856	890
U.S. commercial and other | Aeronautics
Segment Reporting Information [Line Items]
Net sales									79	184	186
U.S. commercial and other | MFC
Segment Reporting Information [Line Items]
Net sales									11	142	184
U.S. commercial and other | RMS
Segment Reporting Information [Line Items]
Net sales									413	503	474
U.S. commercial and other | Space
Segment Reporting Information [Line Items]
Net sales									41	27	46
Fixed-price
Segment Reporting Information [Line Items]
Net sales									39,106	36,205	33,239
Fixed-price | Aeronautics
Segment Reporting Information [Line Items]
Net sales									18,477	17,239	15,719
Fixed-price | MFC
Segment Reporting Information [Line Items]
Net sales									7,587	6,449	5,653
Fixed-price | RMS
Segment Reporting Information [Line Items]
Net sales									10,795	10,382	9,975
Fixed-price | Space
Segment Reporting Information [Line Items]
Net sales									2,247	2,135	1,892
Cost-reimbursable
Segment Reporting Information [Line Items]
Net sales									26,292	23,607	20,523
Cost-reimbursable | Aeronautics
Segment Reporting Information [Line Items]
Net sales									7,789	6,454	5,523
Cost-reimbursable | MFC
Segment Reporting Information [Line Items]
Net sales									3,670	3,682	2,809
Cost-reimbursable | RMS
Segment Reporting Information [Line Items]
Net sales									5,200	4,746	4,275
Cost-reimbursable | Space
Segment Reporting Information [Line Items]
Net sales									9,633	8,725	7,916
Products
Segment Reporting Information [Line Items]
Net sales									54,928	50,053	45,005
Products | Aeronautics
Segment Reporting Information [Line Items]
Net sales									22,327	20,319	18,207
Products | MFC
Segment Reporting Information [Line Items]
Net sales									9,804	8,424	6,945
Products | RMS
Segment Reporting Information [Line Items]
Net sales									12,748	12,206	11,714
Products | Space
Segment Reporting Information [Line Items]
Net sales									10,049	9,104	8,139
Services
Segment Reporting Information [Line Items]
Net sales									10,470	9,759	8,757
Services | Aeronautics
Segment Reporting Information [Line Items]
Net sales									3,939	3,374	3,035
Services | MFC
Segment Reporting Information [Line Items]
Net sales									1,453	1,707	1,517
Services | RMS
Segment Reporting Information [Line Items]
Net sales									3,247	2,922	2,536
Services | Space
Segment Reporting Information [Line Items]
Net sales									$ 1,831	$ 1,756	$ 1,669