Business Dispositions (Details 2) (Unaudited) (USD $)	6 Months Ended	12 Months Ended	3 Months Ended		6 Months Ended
	Jun. 30, 2010 Advisory Services Division	Dec. 31, 2009 Advisory Services Division	Jun. 30, 2011 Shipbuilding Segment	Jun. 30, 2010 Shipbuilding Segment	Jun. 30, 2011 Shipbuilding Segment	Jun. 30, 2010 Shipbuilding Segment	Jun. 30, 2010 NSTec Joint Venture
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
Total debt			$ 1,200,000,000		$ 1,200,000,000
Aggregate principal amount			650,000,000		650,000,000
Term loan			575,000,000		575,000,000
Debt proceeds used for cash contribution					1,429,000,000
Shipbuilding spinoff non-deductible transaction costs					27,000,000	11,000,000
Shipbuilding spinoff total transaction costs					59,000,000
Proceeds from disposition		1,650,000,000
Gain from discontinued operations, net of tax		15,000,000	0	0	1,000,000	7,000,000
Sales and service revenues			0	1,596,000,000	1,646,000,000	3,314,000,000	288,000,000
Additional gain from discontinued operations, net of tax	$ 7,000,000