Goodwill and Acquired Intangibles - Changes in the Carrying Amount of Goodwill by Segment (Detail) - USD ($) $ in Millions	12 Months Ended
	Dec. 31, 2018	Dec. 31, 2017
Goodwill [Roll Forward]
Goodwill, beginning balance	$ 10,807	$ 10,764
Other	(38)	43
Goodwill, ending balance	10,769	10,807
Aeronautics
Goodwill [Roll Forward]
Goodwill, beginning balance	171	171
Other	0	0
Goodwill, ending balance	171	171
MFC
Goodwill [Roll Forward]
Goodwill, beginning balance	2,265	2,260
Other	(3)	5
Goodwill, ending balance	2,262	2,265
RMS
Goodwill [Roll Forward]
Goodwill, beginning balance	6,784	6,748
Other	(33)	36
Goodwill, ending balance	6,751	6,784
Space
Goodwill [Roll Forward]
Goodwill, beginning balance	1,587	1,585
Other	(2)	2
Goodwill, ending balance	$ 1,585	$ 1,587