Segment Information (Details) - USD ($) $ in Millions		3 Months Ended		6 Months Ended
		Jul. 01, 2018	Jul. 02, 2017	Jul. 01, 2018	Jul. 02, 2017	Dec. 31, 2017
Segment Reporting Information [Line Items]
Revenue		$ 9,186	$ 7,675	$ 16,721	$ 15,116
Operating earnings		1,088	1,067	2,096	2,113
Capital expenditures				279	153
Depreciation and amortization				327	220
Identifiable assets		47,152		47,152		$ 35,046
Aerospace
Segment Reporting Information [Line Items]
Revenue		1,895	2,078	3,720	4,152
Operating earnings		386	421	732	860
Capital expenditures				102	50
Depreciation and amortization				72	77
Identifiable assets		10,990		10,990		10,126
Combat Systems
Segment Reporting Information [Line Items]
Revenue		1,534	1,414	2,974	2,701
Operating earnings		236	225	460	430
Capital expenditures				26	31
Depreciation and amortization				42	42
Identifiable assets		10,110		10,110		9,846
Information Technology
Segment Reporting Information [Line Items]
Revenue		2,442	1,052	3,580	2,110
Operating earnings		156	87	257	177
Capital expenditures				21	4
Depreciation and amortization				120	15
Identifiable assets		14,918		14,918		3,021
Mission Systems
Segment Reporting Information [Line Items]
Revenue		1,147	1,052	2,245	2,140
Operating earnings		153	153	299	299
Capital expenditures				26	25
Depreciation and amortization				33	29
Identifiable assets		6,079		6,079		5,856
Marine Systems
Segment Reporting Information [Line Items]
Revenue		2,168	2,079	4,202	4,013
Operating earnings		195	178	379	339
Capital expenditures				81	37
Depreciation and amortization				55	51
Identifiable assets		2,917		2,917		2,906
Corporate
Segment Reporting Information [Line Items]
Revenue		0	0	0	0
Operating earnings		(38)	3	(31)	8
Capital expenditures				23	6
Depreciation and amortization				5	6
Identifiable assets	[1]	2,138		2,138		$ 3,291
U.S. Government
Segment Reporting Information [Line Items]
Revenue		6,204	4,662	10,862	9,177
U.S. Government | Aerospace
Segment Reporting Information [Line Items]
Revenue		108	41	165	90
U.S. Government | Combat Systems
Segment Reporting Information [Line Items]
Revenue		746	744	1,423	1,463
U.S. Government | Information Technology
Segment Reporting Information [Line Items]
Revenue		2,370	981	3,448	1,974
U.S. Government | Mission Systems
Segment Reporting Information [Line Items]
Revenue		908	840	1,775	1,699
U.S. Government | Marine Systems
Segment Reporting Information [Line Items]
Revenue		2,072	2,056	4,051	3,951
U.S. Government | Corporate
Segment Reporting Information [Line Items]
Revenue		$ 0	$ 0	$ 0	$ 0

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