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Commitments And Contingencies [Line Items]

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Years remaining on debt instruments.

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Number Of Aircrafts Expected To Take Delivery, Year Two And Three

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Percentage of employees represented by labor organizations

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Amount of contractual obligation, including, but not limited to, long-term debt, lease obligation, purchase obligation, and other commitments.

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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.

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Commitments and Contingencies - Narrative (Details) $ in Millions	3 Months Ended
	Mar. 31, 2024 USD ($) employee	Apr. 17, 2024 aircraft
United Airlines, Inc.
Commitments and Contingencies [Line Items]
Number of employees \| employee	104,500
Percentage of employees represented by various U.S. labor organizations	83.00%
Tax-Exempt Special Facilities Revenue Bonds
Commitments and Contingencies [Line Items]
Aggregate principal amount of guarantee	$ 1,900
Aircraft Mortgage Debt
Commitments and Contingencies [Line Items]
Aggregate principal amount of guarantee	73
Floating Rate Debt
Commitments and Contingencies [Line Items]
Long-term debt	$ 10,100
Remaining term of debt	12 years
Loans and Leases from Non-U.S. Entities
Commitments and Contingencies [Line Items]
Remaining term of debt	12 years
Aggregate balance	$ 6,900
Subsequent Event \| A321neo
Commitments and Contingencies [Line Items]
Number of aircrafts with expected deliveries in 2026 and 2027 \| aircraft		35