Summary of Scheduled Future Minimum Lease Payments Under Aircraft Operating Leases (Detail) (USD $) In Millions, unless otherwise specified	Jun. 30, 2013
Capacity Purchase Agreements
Commitments and Contingencies Disclosure [Line Items]
Last six months of 2013	$ 968
2014	1,722
2015	1,626
2016	1,400
2017	1,278
After 2017	4,388
Contractual Obligation, Total	11,382
Aircraft Operating Leases
Commitments and Contingencies Disclosure [Line Items]
Last six months of 2013	714
2014	1,571
2015	1,355
2016	1,122
2017	1,009
After 2017	2,590
Operating leases obligations	$ 8,361

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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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