Business Dispositions and Discontinued Operations (Unaudited) #2 (Details) (USD $) In Millions, except Share data, unless otherwise specified	9 Months Ended		3 Months Ended	9 Months Ended
	Sep. 30, 2012	Sep. 30, 2011	Mar. 31, 2011 Shipbuilding Segment	Sep. 30, 2011 Shipbuilding Segment
Income Statement, Balance Sheet and Additional Disclosures by Disposal Groups, Including Discontinued Operations [Line Items]
Pro rata shares			6
Total shares distributed			48,800,000
Debt proceeds used for cash contribution	$ 0	$ 1,429	$ 1,400
Shipbuilding spinoff non-deductible transaction costs				$ 28