Employee Severance and Termination Costs (Details) (USD $) In Millions, unless otherwise specified	12 Months Ended
	Dec. 31, 2011	Dec. 31, 2010
Employee severance and other termination costs incurred by reportable segment
Employee severance and other related termination costs	$ 24	$ 17
C3ISR [Member]
Employee severance and other termination costs incurred by reportable segment
Employee severance and other related termination costs	1	3
Government Services [Member]
Employee severance and other termination costs incurred by reportable segment
Employee severance and other related termination costs	5
AM&M [Member]
Employee severance and other termination costs incurred by reportable segment
Employee severance and other related termination costs	3	3
Electronic Systems [Member]
Employee severance and other termination costs incurred by reportable segment
Employee severance and other related termination costs	$ 15	$ 11