Inventories (Narrative) (Details) (USD $) In Millions, unless otherwise specified	Dec. 31, 2011		Sep. 30, 2011	Dec. 31, 2010
Inventories [Line Items]
Long-term contracts in progress	$ 13,587			$ 14,400
Capitalized precontract costs	1,728			527
Reclassification of previously recorded reach forward losses from accrued liabilities to inventories	501	[1]		2,743	[1]
Amounts credited in cash or other consideration (early issue sales consideration), to airline customers	2,564			1,970
Completed but unsold aircraft	509
Airplane Program 787 [Member]
Inventories [Line Items]
Inventory, work in process	16,098			9,461
Supplier advances	1,770			1,956
Unamortized tooling and other non-recurring costs	1,914			1,447
Deferred production costs	10,753
Deferred production, unamortized tooling and other nonrecurring costs to be recovered from future orders	3,499
Deferred production, unamortized tooling and other nonrecurring costs to be recovered from firm orders at the balance sheet date	9,168
Airplane Program 747 [Member]
Inventories [Line Items]
Unamortized tooling and other non-recurring costs	852			879
Deferred production costs	448
Deferred production, unamortized tooling and other nonrecurring costs to be recovered from future orders	397
Deferred production, unamortized tooling and other nonrecurring costs to be recovered from firm orders at the balance sheet date	903
Reclassification of previously recorded reach forward losses from accrued liabilities to inventories			1,934
A-12 Program [Member]
Inventories [Line Items]
Long-term contracts in progress	236			236
ULA [Member]
Inventories [Line Items]
Delta launch program inventory included in long-term contracts in progress	1,085			1,385
Reduction in earnings in the event ULA is unable to sell additional Delta II inventory	58
ULA [Member] | Unsold Launches [Member]
Inventories [Line Items]
Delta launch program inventory included in long-term contracts in progress	$ 739

[1] Forward loss recognition in 2011 relates primarily to the Airborne Early Warning and Control program (AEW&C). $1,934 of loss related to the 747 Program included in the 2010 balance was reclassified to inventory during 2011.