- Summary of Financial Information (Details) - USD ($) $ in Millions		3 Months Ended		9 Months Ended
		Sep. 30, 2018	Oct. 01, 2017	Sep. 30, 2018	Oct. 01, 2017	Dec. 31, 2017
Segment Reporting Information [Line Items]
Revenue		$ 9,094	$ 7,580	$ 25,815	$ 22,696
Operating earnings		1,135	1,063	3,231	3,176
Capital expenditures				447	273
Depreciation and amortization				542	326
Identifiable assets		46,963		46,963		$ 35,046
Aerospace
Segment Reporting Information [Line Items]
Revenue		2,031	1,995	5,751	6,147
Combat Systems
Segment Reporting Information [Line Items]
Revenue		1,523	1,500	4,497	4,201
Information Technology
Segment Reporting Information [Line Items]
Revenue		2,307	1,068	5,887	3,178
Mission Systems
Segment Reporting Information [Line Items]
Revenue		1,230	1,086	3,475	3,226
Marine Systems
Segment Reporting Information [Line Items]
Revenue		2,003	1,931	6,205	5,944
U.S. Government
Segment Reporting Information [Line Items]
Revenue		5,984	4,626	16,846	13,803
U.S. Government | Aerospace
Segment Reporting Information [Line Items]
Revenue		48	48	213	138
U.S. Government | Combat Systems
Segment Reporting Information [Line Items]
Revenue		765	754	2,188	2,217
U.S. Government | Information Technology
Segment Reporting Information [Line Items]
Revenue		2,245	1,011	5,693	2,985
U.S. Government | Mission Systems
Segment Reporting Information [Line Items]
Revenue		994	892	2,769	2,591
U.S. Government | Marine Systems
Segment Reporting Information [Line Items]
Revenue		1,932	1,921	5,983	5,872
Operating Segments | Aerospace
Segment Reporting Information [Line Items]
Revenue		2,031	1,995	5,751	6,147
Operating earnings		376	381	1,108	1,241
Capital expenditures				142	87
Depreciation and amortization				112	112
Identifiable assets		11,444		11,444		10,126
Operating Segments | Combat Systems
Segment Reporting Information [Line Items]
Revenue		1,523	1,500	4,497	4,201
Operating earnings		241	247	701	677
Capital expenditures				47	49
Depreciation and amortization				64	63
Identifiable assets		10,584		10,584		9,846
Operating Segments | Information Technology
Segment Reporting Information [Line Items]
Revenue		2,307	1,068	5,887	3,178
Operating earnings		157	101	414	278
Capital expenditures				36	9
Depreciation and amortization				229	23
Identifiable assets		14,674		14,674		3,021
Operating Segments | Mission Systems
Segment Reporting Information [Line Items]
Revenue		1,230	1,086	3,475	3,226
Operating earnings		179	152	478	451
Capital expenditures				39	34
Depreciation and amortization				49	43
Identifiable assets		6,093		6,093		5,856
Operating Segments | Marine Systems
Segment Reporting Information [Line Items]
Revenue		2,003	1,931	6,205	5,944
Operating earnings		169	179	548	518
Capital expenditures				147	71
Depreciation and amortization				83	79
Identifiable assets		2,945		2,945		2,906
Operating Segments | U.S. Government | Aerospace
Segment Reporting Information [Line Items]
Revenue		48	48	213	138
Operating Segments | U.S. Government | Combat Systems
Segment Reporting Information [Line Items]
Revenue		765	754	2,188	2,217
Operating Segments | U.S. Government | Information Technology
Segment Reporting Information [Line Items]
Revenue		2,245	1,011	5,693	2,985
Operating Segments | U.S. Government | Mission Systems
Segment Reporting Information [Line Items]
Revenue		994	892	2,769	2,591
Operating Segments | U.S. Government | Marine Systems
Segment Reporting Information [Line Items]
Revenue		1,932	1,921	5,983	5,872
Corporate
Segment Reporting Information [Line Items]
Revenue		0	0	0	0
Operating earnings		13	3	(18)	11
Capital expenditures				36	23
Depreciation and amortization				5	6
Identifiable assets	[1]	1,223		1,223		$ 3,291
Corporate | U.S. Government
Segment Reporting Information [Line Items]
Revenue		$ 0	$ 0	$ 0	$ 0

[1] Corporate identifiable assets are primarily cash and equivalents.