Segment Information (Unaudited) (Details) (USD $) In Millions, unless otherwise specified	3 Months Ended
	Mar. 31, 2013 segment	Mar. 31, 2012
Segment Reporting Information [Line Items]
Number of reportable segments	4
Sales	$ 6,104	$ 6,198
Operating income	759	796
Net FAS/CAS pension adjustment	33	32
Unallocated corporate expenses	(19)	(23)
Other	(3)	(2)
Aerospace Systems
Segment Reporting Information [Line Items]
Sales	2,485	2,383
Operating income	270	279
Electronic Systems
Segment Reporting Information [Line Items]
Sales	1,721	1,724
Operating income	296	304
Information Systems
Segment Reporting Information [Line Items]
Sales	1,674	1,844
Operating income	171	205
Technical Services
Segment Reporting Information [Line Items]
Sales	717	750
Operating income	65	70
Intersegment eliminations
Segment Reporting Information [Line Items]
Sales	(493)	(503)
Operating income	(54)	(69)
Total segment operating income [Member]
Segment Reporting Information [Line Items]
Operating income	$ 748	$ 789