Segment Information (Details 2) - USD ($) $ in Millions	3 Months Ended								12 Months Ended
	Dec. 31, 2015	Sep. 30, 2015	Jun. 30, 2015	Mar. 31, 2015	Dec. 31, 2014	Sep. 30, 2014	Jun. 30, 2014	Mar. 31, 2014	Dec. 31, 2015	Dec. 31, 2014	Dec. 31, 2013
Intersegment sales and operating income (Table Amounts) [Abstract]
Total sales	$ 5,694	$ 5,979	$ 5,896	$ 5,957	$ 6,108	$ 5,984	$ 6,039	$ 5,848	$ 23,526	$ 23,979	$ 24,661
Operating income	$ 689	$ 794	$ 813	$ 780	$ 762	$ 769	$ 820	$ 845	3,076	3,196	3,123
Intersegment Eliminations [Member]
Intersegment sales and operating income (Table Amounts) [Abstract]
Total sales									2,052	1,990	1,941
Operating income									238	236	256
Intersegment Eliminations [Member] | Aerospace Systems
Intersegment sales and operating income (Table Amounts) [Abstract]
Total sales									232	176	149
Operating income									28	22	18
Intersegment Eliminations [Member] | Electronic Systems
Intersegment sales and operating income (Table Amounts) [Abstract]
Total sales									544	637	629
Operating income									88	109	125
Intersegment Eliminations [Member] | Information Systems
Intersegment sales and operating income (Table Amounts) [Abstract]
Total sales									592	537	504
Operating income									60	57	63
Intersegment Eliminations [Member] | Technical Services
Intersegment sales and operating income (Table Amounts) [Abstract]
Total sales									684	640	659
Operating income									$ 62	$ 48	$ 50