Summary of Scheduled Future Minimum Lease Payments Under Aircraft Operating Leases (Detail) (USD $) In Millions, unless otherwise specified	Sep. 30, 2013
Capacity Purchase Agreements
Commitments and Contingencies Disclosure [Line Items]
Last three months of 2013	$ 474
2014	1,950
2015	1,773
2016	1,558
2017	1,476
After 2017	4,920
Contractual Obligation, Total	12,151
Aircraft Operating Leases
Commitments and Contingencies Disclosure [Line Items]
Last three months of 2013	306
2014	1,631
2015	1,399
2016	1,165
2017	1,066
After 2017	2,756
Operating leases obligations	$ 8,323

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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

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