Commitments and Contingencies (Details 1) (Airline Capacity Purchase Arrangements [Member], USD $) In Millions, unless otherwise specified	Dec. 31, 2012
Airline Capacity Purchase Arrangements [Member]
Unrecorded Unconditional Purchase Obligation [Line Items]
Unrecorded Unconditional Purchase Obligation, Due in Next Twelve Months	$ 2,210	[1]
Unrecorded Unconditional Purchase Obligation, Due within Two Years	2,200	[1]
Unrecorded Unconditional Purchase Obligation, Due within Three Years	2,130	[1]
Unrecorded Unconditional Purchase Obligation, Due within Four Years	1,850	[1]
Unrecorded Unconditional Purchase Obligation, Due within Five Years	1,690	[1]
Unrecorded Unconditional Purchase Obligation, Due after Five Years	3,880	[1]
Unrecorded Unconditional Purchase Obligation	$ 13,960	[1]

[1] These amounts exclude Contract Carrier payments accounted for as operating leases of aircraft, which are described in Note 9. The contingencies described below under “Contingencies Related to Termination of Contract Carrier Agreements” are also excluded from this table.