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

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Contractual interest rate for funds borrowed, under the debt agreement.

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Amount of borrowing capacity currently available under the credit facility (current borrowing capacity less the amount of borrowings outstanding).

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The cash inflow during the period from additional borrowings in aggregate debt. Includes proceeds from short-term and long-term debt.

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Debt - Narrative (Details) - Secured Debt - USD ($)	12 Months Ended
Debt - Narrative (Details) - Secured Debt - USD ($)	Dec. 31, 2022	Apr. 21, 2021
Debt Instrument [Line Items]
Proceeds from issuance of debt	$ 752,000,000
Minimum
Debt Instrument [Line Items]
Stated interest rate	4.00%
Maximum
Debt Instrument [Line Items]
Stated interest rate	5.90%
Revolving Credit Facility \| United Airlines, Inc.
Debt Instrument [Line Items]
Available under revolving credit facility	$ 1,750,000,000
Term Loan B Facility due 2028
Debt Instrument [Line Items]
Aggregate principal amount		$ 5,000,000,000