Financial Instruments And Risk Management (Narrative) (Details) (USD $) In Millions, unless otherwise specified	3 Months Ended		6 Months Ended
	Jun. 30, 2013 barrel	Jun. 30, 2012	Jun. 30, 2013 barrel	Jun. 30, 2012	Dec. 31, 2012
Derivative Instruments and Hedging Activities Disclosure [Abstract]
Number of barrels of jet fuel derivative contracts outstanding (barrels)	22,000,000		22,000,000
Fuel derivative maturity in months			18 months
Derivative instruments, gain (loss) recognized in income, net	$ (31)	$ (9)	$ (23)	$ 20
Price risk cash flow dedge derivative, at fair value, net	5		5		62
Derivative instruments, gain (loss) reclassification from accumulated OCI to income, estimate of time to transfer			12 months
Derivative instruments, gain (loss) reclassification from accumulated OCI to income, estimated net amount to be transferred			$ (36)