Goodwill and Acquired Intangibles - Changes in the Carrying Amount of Goodwill by Segment (Detail) - USD ($) $ in Millions	12 Months Ended
	Dec. 31, 2017	Dec. 31, 2016
Goodwill [Roll Forward]
Goodwill, beginning balance	$ 10,764	$ 10,695
Purchase accounting adjustments		78
Other	43	(9)
Goodwill, ending balance	10,807	10,764
Aeronautics
Goodwill [Roll Forward]
Goodwill, beginning balance	171	171
Purchase accounting adjustments		0
Other	0	0
Goodwill, ending balance	171	171
MFC
Goodwill [Roll Forward]
Goodwill, beginning balance	2,260	2,198
Purchase accounting adjustments		0
Other	5	62
Goodwill, ending balance	2,265	2,260
RMS
Goodwill [Roll Forward]
Goodwill, beginning balance	6,748	6,738
Purchase accounting adjustments		78
Other	36	(68)
Goodwill, ending balance	6,784	6,748
Space
Goodwill [Roll Forward]
Goodwill, beginning balance	1,585	1,588
Purchase accounting adjustments		0
Other	2	(3)
Goodwill, ending balance	$ 1,587	$ 1,585