Accounts Receivable, Net (Details) (USD $) In Millions, unless otherwise specified	Dec. 31, 2013	Dec. 31, 2012
Accounts Receivable, Net [Abstract]
Total accounts receivable	$ 2,754	$ 2,918
Allowance for doubtful accounts	(69)	(60)
Total accounts receivable, net	2,685	2,858
U.S. Government Sales
Accounts Receivable, Net [Abstract]
Billed	596	783
Unbilled	5,801	5,284
Progress and performance-based payments received	(4,385)	(3,907)
Total accounts receivable	2,012	2,160
Other Customers
Accounts Receivable, Net [Abstract]
Billed	296	325
Unbilled	2,830	1,992
Progress and performance-based payments received	(2,384)	(1,559)
Total accounts receivable	$ 742	$ 758