Summary of Scheduled Future Minimum Lease Payments Under Aircraft Operating Leases (Detail) $ in Millions	Sep. 30, 2015 USD ($)
Capacity Purchase Agreements
Commitments and Contingencies Disclosure [Line Items]
Last three months of 2015	$ 460
2016	1,836
2017	1,725
2018	1,332
2019	1,103
After 2019	5,314
Contractual Obligation, Total	11,770
Aircraft Operating Leases
Commitments and Contingencies Disclosure [Line Items]
Last three months of 2015	291
2016	1,322
2017	1,292
2018	1,068
2019	868
After 2019	3,095
Operating leases obligations	$ 7,936

Commitments and Contingencies Disclosure [Line Items]

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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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