Acquisitions and Divestitures, Goodwill and Intangible Assets - Changes In Amount of Goodwill (Details) $ in Millions	6 Months Ended
	Jun. 30, 2019 USD ($)
Goodwill [Roll Forward]
Goodwill, beginning of period	$ 19,594	[1]
Acquisitions/divestitures	92	[2]
Other	(24)	[3]
Goodwill, end of period	19,662	[1]
Aerospace
Goodwill [Roll Forward]
Goodwill, beginning of period	2,813	[1]
Acquisitions/divestitures	2	[2]
Other	13	[3]
Goodwill, end of period	2,828	[1]
Combat Systems
Goodwill [Roll Forward]
Goodwill, beginning of period	2,633	[1]
Acquisitions/divestitures	7	[2]
Other	32	[3]
Goodwill, end of period	2,672	[1]
Information Technology
Goodwill [Roll Forward]
Goodwill, beginning of period	9,622	[1]
Acquisitions/divestitures	77	[2]
Other	1	[3]
Goodwill, end of period	9,700	[1]
Accumulated impairment losses	536
Mission Systems
Goodwill [Roll Forward]
Goodwill, beginning of period	4,229	[1]
Acquisitions/divestitures	6	[2]
Other	(70)	[3]
Goodwill, end of period	4,165	[1]
Accumulated impairment losses	1,300
Marine Systems
Goodwill [Roll Forward]
Goodwill, beginning of period	297	[1]
Acquisitions/divestitures	0	[2]
Other	0	[3]
Goodwill, end of period	$ 297	[1]

[1] Goodwill in the Information Technology and Mission Systems reporting units is net of $536 and $1.3 billion of accumulated impairment losses, respectively.

[2] Includes adjustments during the purchase price allocation period.

[3] Consists primarily of adjustments for foreign currency translation