Summary of Scheduled Future Minimum Lease Payments Under Aircraft Operating Leases (Detail) (USD $) In Millions, unless otherwise specified	Sep. 30, 2014
Capacity Purchase Agreements
Commitments and Contingencies Disclosure [Line Items]
Last three months of 2014	$ 460
2015	1,665
2016	1,531
2017	1,479
2018	1,416
After 2018	5,054
Contractual Obligation, Total	11,605
Aircraft Operating Leases
Commitments and Contingencies Disclosure [Line Items]
Last three months of 2014	296
2015	1,442
2016	1,265
2017	1,190
2018	960
After 2018	3,194
Operating leases obligations	$ 8,347

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Amount of required minimum rental payments for leases having an initial or remaining non-cancelable letter-terms in excess of one year.

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 840

-SubTopic 20

-Section 50

-Paragraph 2

-Subparagraph (a)

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-Publisher FASB

-Name Accounting Standards Codification

-Topic 840

-SubTopic 10

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-Paragraph 40

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