Variable Interest Entities (Details)	Dec. 31, 2018 aircraft
Mainline
Variable Interest Entity [Line Items]
Aircraft under operating lease, fixed purchase options	23
Regional Carrier
Variable Interest Entity [Line Items]
Aircraft under operating lease	90

Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table.

No definition available.

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