Condensed Consolidated Statements of Changes in Shareholders' Equity (Unaudited) (USD $) In Millions, except Per Share data	Total	Common Stock	Paid-in Capital	Retained Earnings	Accumulated Other Comprehensive Loss
Beginning of year at Dec. 31, 2010				$ 8,124
Beginning of year at Dec. 31, 2010					(2,757)
Beginning of year at Dec. 31, 2010		291
Beginning of year at Dec. 31, 2010			7,778
Common stock repurchased		(28)	(1,626)
Stock awards and options		3	182
Spin-off of shipbuilding business			(1,874)		524
Net earnings	1,570			1,570
Dividends declared				(414)
Other comprehensive income, net of tax	57				57
Total shareholders' equity	11,830
Cash dividends declared per share	$ 1.47
End of period at Sep. 30, 2011				9,280
End of period at Sep. 30, 2011					(2,176)
End of period at Sep. 30, 2011		266
End of period at Sep. 30, 2011			4,460
Beginning of year at Dec. 31, 2011	9,699			9,699
Beginning of year at Dec. 31, 2011	(3,490)				(3,490)
Beginning of year at Dec. 31, 2011	254	254
Beginning of year at Dec. 31, 2011	3,873		3,873
Common stock repurchased		(14)	(831)
Stock awards and options		6	249
Spin-off of shipbuilding business			5		0
Net earnings	1,445			1,445
Dividends declared				(405)
Other comprehensive income, net of tax	156				156
Total shareholders' equity	10,947
Cash dividends declared per share	$ 1.60
End of period at Sep. 30, 2012	10,739			10,739
End of period at Sep. 30, 2012	(3,334)				(3,334)
End of period at Sep. 30, 2012	246	246
End of period at Sep. 30, 2012	$ 3,296		$ 3,296