Cost Of Contracts (Detail) (USD $) In Millions, unless otherwise specified	Dec. 31, 2012	Dec. 31, 2011
Contracts In Process [Line Items]
Contract costs and estimated profits	$ 8,162	$ 18,807
Other contract costs	1,089	959
Costs in excess of billings on uncompleted contracts or programs, total	9,251	19,766
Advances and progress payments	(4,287)	(14,598)
Total contracts in process	4,964	5,168
Percent of contracts-in-process not expected to be billed in 2013	15.00%
Canadian Maritime Helicopter Project (MHP)
Contracts In Process [Line Items]
Contracts-in-process not expected to bill in 2013	$ 365