Arrangements With Off-Balance Sheet Risk (Third Party Guarantees) (Details) (USD $) In Millions, unless otherwise specified	Sep. 30, 2013	Dec. 31, 2012
Contingent Repurchase Commitments [Member]
Guarantor Obligations [Line Items]
Maximum Potential Payments	$ 1,909	$ 2,065
Estimated Proceeds from Collateral or Recourse1	1,906	2,065
Carrying Amount of Liabilities	5	5
Contributed Delta Program Launch Inventory [Member]
Guarantor Obligations [Line Items]
Maximum Potential Payments	127	137
Contract Pricing [Member]
Guarantor Obligations [Line Items]
Maximum Potential Payments	261	261
Carrying Amount of Liabilities	7	7
Other Delta Contracts [Member]
Guarantor Obligations [Line Items]
Maximum Potential Payments	227	232
Carrying Amount of Liabilities	8	8
Other Indemnifications [Member]
Guarantor Obligations [Line Items]
Maximum Potential Payments	111	137
Carrying Amount of Liabilities	$ 28	$ 32