Variable Interest Entities ("VIE") (Details) $ in Billions	Dec. 31, 2019 USD ($) aircraft
Tax-Exempt Special Facilities Revenue Bonds
Variable Interest Entity [Line Items]
Underlying debt and interest \| $	$ 1.9
Mainline Aircraft
Variable Interest Entity [Line Items]
Aircraft under operating lease, fixed purchase options	6
Regional Aircraft
Variable Interest Entity [Line Items]
Aircraft under operating lease	60

Number of Aircraft under Operating Lease Agreements with Fixed Price Purchase Options

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- Definition

Number of aircraft under operating lease agreements with purchase options at prices potentially below fair value.

+ References

No definition available.

+ Details

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- Definition

Maximum potential amount of future payments (undiscounted) the guarantor could be required to make under the guarantee or each group of similar guarantees before reduction for potential recoveries under recourse or collateralization provisions.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 460
-SubTopic 10
-Section 50
-Paragraph 4
-Subparagraph (b)(1)
-URI http://asc.fasb.org/extlink&oid=118943654&loc=d3e12069-110248

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- Definition

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.

+ References

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