Financial Instruments And Risk Management (Narrative) (Details) (USD $) In Millions, unless otherwise specified	9 Months Ended
Sep. 30, 2013 barrel	Dec. 31, 2012
Derivative Instruments and Hedging Activities Disclosure [Abstract]
Number of barrels of jet fuel derivative contracts outstanding (barrels)	19,000,000
Fuel derivative maturity in months	18 months
Price risk cash flow hedge derivative, at fair value, net	$ 51	$ 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	$ (9)

Aggregate notional amount of derivative expressed in nonmonetary units. For example, the number of barrels specified in a fuel oil forward purchase contract.

Reference 1: http://www.xbrl.org/2003/role/presentationRef

-Publisher SEC

-Name Regulation S-X (SX)

-Number 210

-Article 12

-Section 13

-Sentence Column B

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- Definition

High end period remaining until maturity for the derivative contract, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days.

+ References

No definition available.

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- Definition

The estimated value of gains (losses), net anticipated to be transferred in the future from accumulated other comprehensive income into earnings.

+ References

No definition available.

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- Definition

Estimated period for the anticipated transfer of gain (loss), net, from accumulated other comprehensive income into earnings, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days.

+ References

No definition available.

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- Definition

Fair value as of the balance sheet date of all price risk derivatives designated as cash flow hedging instruments.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 815

-SubTopic 10

-Section 45

-Paragraph 5

-URI http://asc.fasb.org/extlink&oid=6945355&loc=d3e41228-113958

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