Segment Information (Details 1) (Unaudited) (USD $) In Millions	3 Months Ended		9 Months Ended
	Sep. 30, 2011	Sep. 30, 2010	Sep. 30, 2011	Sep. 30, 2010
Sales and Service Revenues by Segment (Table Amounts) [Abstract]
Total sales and service revenues	$ 6,612	$ 7,071	$ 19,906	$ 21,240
Aerospace Systems
Sales and Service Revenues by Segment (Table Amounts) [Abstract]
Total sales and service revenues	2,572	2,706	7,900	8,244
Electronic Systems
Sales and Service Revenues by Segment (Table Amounts) [Abstract]
Total sales and service revenues	1,905	1,874	5,504	5,740
Information Systems
Sales and Service Revenues by Segment (Table Amounts) [Abstract]
Total sales and service revenues	1,955	2,123	6,011	6,310
Technical Services
Sales and Service Revenues by Segment (Table Amounts) [Abstract]
Total sales and service revenues	680	871	2,024	2,435
Intersegment eliminations
Sales and Service Revenues by Segment (Table Amounts) [Abstract]
Total sales and service revenues	$ (500)	$ (503)	$ (1,533)	$ (1,489)