Debt - Details of Pass Through Trusts (Details) - USD ($)	12 Months Ended
Dec. 31, 2021	Dec. 31, 2020	Dec. 31, 2019
Debt Instrument [Line Items]
Proceeds received from issuance of debt	$ 11,096,000,000	$ 15,676,000,000	$ 1,786,000,000
Class B EETC - Issued February 2021 \| Pass-Through Certificates
Debt Instrument [Line Items]
Face Amount	$ 600,000,000
Stated interest rate	4.88%
Proceeds received from issuance of debt	$ 600,000,000

Face (par) amount of debt instrument at time of issuance.

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