Legal Proceedings (Details) (USD $) In Millions, unless otherwise specified	Sep. 30, 2012	Dec. 31, 2011	Sep. 30, 2012 A12 Program [Member]	Nov. 09, 2006 BSSI/Telesat Canada [Member]	Sep. 30, 2012 A12 Program [Member]	Sep. 30, 2012 A12 Program [Member] Unliquidated Progress Payments [Member]	Dec. 29, 2009 A12 Program [Member] Unliquidated Progress Payments [Member]	Sep. 30, 2012 A12 Program [Member] Program Termination [Member]	Sep. 30, 2012 A12 Program [Member] Interest On Unliquidated Progress Payments [Member]	Nov. 09, 2006 BSSI/Telesat Canada [Member] Initial Damages Sought [Member]	Nov. 09, 2006 BSSI/Telesat Canada [Member] Initial Lost Profits Sought [Member]	Apr. 11, 2012 BSSI/Telesat Canada [Member] Minimum [Member] Revised Damages Sought [Member]	Apr. 11, 2012 BSSI/Telesat Canada [Member] Maximum [Member] Revised Damages Sought [Member]	Sep. 30, 2012 A12 Program [Member]	Dec. 31, 2011 A12 Program [Member]
Legal Proceedings [Line Items]
Inventory For long-term contracts or programs gross					$ 587
Inventory Valuation Reserves					350
Loss contingency, estimate of possible loss					1,738	1,350	1,352	275	1,580	385	10	42	71
Inventories, net of advances and progress billings	36,817	32,240												237	236
Long-term contracts in progress	15,082	13,587
Unrecorded gain contingency			$ 1,185	$ 15