Contracts in Process (Details) (USD $) In Millions, unless otherwise specified	12 Months Ended
	Dec. 31, 2011	Dec. 31, 2010	Dec. 31, 2009
Components of contracts in process
Unbilled contract receivables, gross	$ 2,926	$ 2,769
Unliquidated progress payments	(1,146)	(1,007)
Unbilled contract receivables, net	1,780	1,762
Inventoried contract costs, gross	928	882
Unliquidated progress payments	(79)	(96)
Inventoried contract costs, net	849	786
Total contracts in process	2,629	2,548
General & Administrative, Independent Research & Development and Bid and Proposal Costs
Amounts included in inventoried contract costs at beginning of the year	97	77	74
Add: IRAD and B&P costs incurred	348	344	324
Other G&A costs incurred	963	987	990
Total contract costs incurred	1,311	1,331	1,314
Less: Amounts charged to cost of sales	(1,317)	(1,311)	(1,311)
Amounts included in inventoried contract costs at end of the year	91	97	77
Selling, general and administrative expenses and research and development expenses
Selling, general and administrative expenses	298	279	250
Research and development expenses	73	68	59
Total	$ 371	$ 347	$ 309
Contracts In Process (Textual)
Percentage of unbilled contract receivables billed and collected within one year	92.00%
Percentage of incurred costs billed, minimum	75.00%
Percentage of incurred costs billed, maximum	80.00%