Number of persons employed by the Entity

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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 That Are Delayed

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Percentage of employees represented by labor organizations

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Sale Leaseback Transaction, Purchase Option, Number Of Leased Assets Expected To Be Purchased In Next Fiscal Year

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Amount of contractual obligation, including but not limited to, long-term debt, capital lease obligations, operating lease obligations, purchase obligations, 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, 2022 USD ($) employee aircraft	Apr. 21, 2022 aircraft
Commitments and Contingencies [Line Items]
Remaining term of debt	11 years
Boeing 737 MAX
Commitments and Contingencies [Line Items]
Sale leaseback transaction, number of leased assets expected to be purchased in next fiscal year \| aircraft	8
Boeing 737 MAX \| Subsequent Event
Commitments and Contingencies [Line Items]
Number of aircraft expected to take delivery that are delayed \| aircraft		7
Boeing 787 \| Subsequent Event
Commitments and Contingencies [Line Items]
Number of aircraft expected to take delivery that are delayed \| aircraft		2
United Airlines, Inc.
Commitments and Contingencies [Line Items]
Number of employees \| employee	87,400
Percentage of employees represented by various U.S. labor organizations	85.00%
Tax-Exempt Special Facilities Revenue Bonds
Commitments and Contingencies [Line Items]
Aggregate principal amount of guarantee	$ 2,100
Aircraft Mortgage Debt
Commitments and Contingencies [Line Items]
Aggregate principal amount of guarantee	102
Floating Rate Debt
Commitments and Contingencies [Line Items]
Debt	$ 13,200
Loans and Leases from Non-U.S. Entities
Commitments and Contingencies [Line Items]
Remaining term of debt	11 years
Aggregate balance	$ 10,000