Segment Information (Segment Reporting Information) (Details) - USD ($) $ in Millions		12 Months Ended
		Dec. 31, 2020	Dec. 31, 2019		Dec. 31, 2018
Segment Reporting Information [Line Items]
Revenue*		$ 37,925	$ 39,350	[1]	$ 36,193	[1]
Operating Earnings		4,133	4,570	[1]	4,394	[1]
Identifiable Assets		51,308	49,349	[1]	45,887
Capital Expenditures		967	987		690
Depreciation and Amortization		878	829		763
U.S. Government
Segment Reporting Information [Line Items]
Revenue*		26,303	25,807		23,606
Aerospace
Segment Reporting Information [Line Items]
Revenue*		8,075	9,801		8,455
Aerospace | U.S. Government
Segment Reporting Information [Line Items]
Revenue*		513	498		334
Marine Systems
Segment Reporting Information [Line Items]
Revenue*		9,979	9,183		8,502
Marine Systems | U.S. Government
Segment Reporting Information [Line Items]
Revenue*		9,871	9,027		8,245
Combat Systems
Segment Reporting Information [Line Items]
Revenue*		7,223	7,007		6,241
Combat Systems | U.S. Government
Segment Reporting Information [Line Items]
Revenue*		4,191	4,048		3,228
Technologies
Segment Reporting Information [Line Items]
Revenue*		12,648	13,359		12,995
Technologies | U.S. Government
Segment Reporting Information [Line Items]
Revenue*		11,728	12,234		11,799
Operating Segments | Aerospace
Segment Reporting Information [Line Items]
Revenue*		8,075	9,801		8,455
Operating Earnings		1,083	1,532		1,490
Identifiable Assets		12,050	12,324		11,220
Capital Expenditures		95	138		194
Depreciation and Amortization		201	178		154
Operating Segments | Aerospace | U.S. Government
Segment Reporting Information [Line Items]
Revenue*		513	498		334
Operating Segments | Marine Systems
Segment Reporting Information [Line Items]
Revenue*		9,979	9,183		8,502
Operating Earnings		854	785		761
Identifiable Assets		4,488	3,918		3,304
Capital Expenditures		604	449		243
Depreciation and Amortization		145	122		116
Operating Segments | Marine Systems | U.S. Government
Segment Reporting Information [Line Items]
Revenue*		9,871	9,027		8,245
Operating Segments | Combat Systems
Segment Reporting Information [Line Items]
Revenue*		7,223	7,007		6,241
Operating Earnings		1,041	996		962
Identifiable Assets		12,034	11,220		9,872
Capital Expenditures		92	109		91
Depreciation and Amortization		95	85		87
Operating Segments | Combat Systems | U.S. Government
Segment Reporting Information [Line Items]
Revenue*		4,191	4,048		3,228
Operating Segments | Technologies
Segment Reporting Information [Line Items]
Revenue*		12,648	13,359		12,995
Operating Earnings		1,211	1,311		1,267
Identifiable Assets		19,663	20,453		20,143
Capital Expenditures		172	222		111
Depreciation and Amortization		428	437		398
Operating Segments | Technologies | U.S. Government
Segment Reporting Information [Line Items]
Revenue*		11,728	12,234		11,799
Corporate
Segment Reporting Information [Line Items]
Revenue*		0	0		0
Operating Earnings		(56)	(54)		(86)
Identifiable Assets	[2]	3,073	1,434		1,348
Capital Expenditures	[2]	4	69		51
Depreciation and Amortization	[2]	9	7		8
Corporate | U.S. Government
Segment Reporting Information [Line Items]
Revenue*		$ 0	$ 0		$ 0

[1] *Prior-period information has been restated for the retrospective application of a change in accounting principle related to the amortization of actuarial gains and losses for our qualified U.S. government pension plans, which we adopted in the fourth quarter of 2020. For further discussion of this change in accounting principle, see Note T to the Consolidated Financial Statements.

[2] *Corporate identifiable assets are primarily cash and equivalents.