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Commitments and Contingencies - Aircraft Purchase Commitments By Period (Details) - Future aircraft purchase commitments
$ in Millions
Mar. 31, 2017
USD ($)
Unrecorded Unconditional Purchase Obligation, Fiscal Year Maturity  
Nine months ending December 31, 2017 $ 2,130
2018 3,140
2019 3,550
2020 1,740
2021 1,130
Thereafter 660
Total $ 12,350