Segment Information (Details Textual) (USD $) In Millions, unless otherwise specified	12 Months Ended
Dec. 31, 2011 Segment	Dec. 31, 2010	Dec. 31, 2009
Segment Information (Textual)
Number of segments	4
Sales reclassified from Government Services segment to Electronic Systems segment as a result of business unit re-alignments		$ 115	$ 143
Sales reclassified from C3ISR segment to Government Services segment as a result of business unit re-alignments		79	79
Operating income reclassified from Government Services segment to Electronic Systems segment as a result of business unit re-alignments		7	16
Operating income reclassified from C3ISR segment to Government Services segment as a result of business unit re-alignments		4	5
Assets reclassified from Government Services segment to Electronic Systems segment as a result of business unit re-alignments		129	162
Assets reclassified from C3ISR segment to Government Services segment as a result of business unit re-alignments		$ 19	$ 19

Assets reclassified from segment one to segment two as result of business unit realignments.

No definition available.

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Assets reclassified from segment two to segment four as result of business unit realignments.

No definition available.

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Number of segments.

No definition available.

Operating income reclassified from segment one to segment two as result of business unit realignments.

No definition available.

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Operating income reclassified from segment two to segment four as result of business unit realignments.

No definition available.

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Sales reclassified from segment one to segment two as result of business unit realignments.

No definition available.

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Sales reclassified from segment two to segment four as result of business unit realignments.

No definition available.

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