Information on Business Segments - Summary of Financial Information for Each Business Segment, Intersegment Sale, Depreciation and Capital Expenditures (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
Depreciation and amortization									1,290	1,189	1,161
Capital expenditures									1,766	1,484	1,278
Aeronautics
Segment Reporting Information [Line Items]
Net sales									26,266	23,693	21,242
Missiles and Fire Control
Segment Reporting Information [Line Items]
Net sales									11,257	10,131	8,462
Rotary and Mission Systems
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
Intersegment sales
Segment Reporting Information [Line Items]
Net sales									3,085	2,956	2,539
Intersegment sales | Aeronautics
Segment Reporting Information [Line Items]
Net sales									243	217	120
Intersegment sales | Missiles and Fire Control
Segment Reporting Information [Line Items]
Net sales									562	515	423
Intersegment sales | Rotary and Mission Systems
Segment Reporting Information [Line Items]
Net sales									1,903	1,872	1,759
Intersegment sales | Space
Segment Reporting Information [Line Items]
Net sales									377	352	237
Operating Segments
Segment Reporting Information [Line Items]
Net sales									65,398	59,812	53,762
Depreciation and amortization									1,181	1,119	1,096
Capital expenditures									1,639	1,356	1,214
Operating Segments | Aeronautics
Segment Reporting Information [Line Items]
Net sales									26,266	23,693	21,242
Depreciation and amortization									348	318	304
Capital expenditures									534	526	460
Operating Segments | Missiles and Fire Control
Segment Reporting Information [Line Items]
Net sales									11,257	10,131	8,462
Depreciation and amortization									138	124	105
Capital expenditures									391	300	244
Operating Segments | Rotary and Mission Systems
Segment Reporting Information [Line Items]
Net sales									15,995	15,128	14,250
Depreciation and amortization									476	464	458
Capital expenditures									311	272	255
Operating Segments | Space
Segment Reporting Information [Line Items]
Net sales									11,880	10,860	9,808
Depreciation and amortization									219	213	229
Capital expenditures									403	258	255
Corporate activities
Segment Reporting Information [Line Items]
Depreciation and amortization									109	70	65
Capital expenditures									$ 127	$ 128	$ 64