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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Amount, excluding unamortized premium (discount) and debt issuance cost, of long-term debt. Excludes lease obligation.

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The amount of loss pertaining to the specified contingency that was charged against earnings in the period, including the effects of revisions in previously reported estimates.

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The minimum number of units that must be purchased, in connection with an unconditional purchase obligation that has not been recognized for financial reporting purposes.

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Commitments and Contingencies - Narrative (Details) $ in Millions	9 Months Ended
	Sep. 30, 2022 USD ($) commitment employee aircraft	Dec. 31, 2022 aircraft	Jul. 21, 2022 aircraft
Commitments and Contingencies [Line Items]
Loss contingency, loss in period	$ 94
Remaining term of debt	10 years
United Airlines, Inc.
Commitments and Contingencies [Line Items]
Number of employees \| employee	90,800
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	$ 2,000
Aircraft Mortgage Debt
Commitments and Contingencies [Line Items]
Aggregate principal amount of guarantee	95
Floating Rate Debt
Commitments and Contingencies [Line Items]
Debt	$ 12,800
Loans and Leases from Non-U.S. Entities
Commitments and Contingencies [Line Items]
Remaining term of debt	10 years
Aggregate balance	$ 9,700
Boeing 787
Commitments and Contingencies [Line Items]
Number of aircraft expected to take delivery that are delayed \| aircraft	3
Number of aircraft committed to purchase \| commitment	7
Boeing 737 MAX
Commitments and Contingencies [Line Items]
Number of aircraft expected to take delivery that are delayed \| aircraft			15
Sale leaseback transaction, number of leased assets expected to be purchased in next fiscal year \| aircraft	8
Number of aircraft committed to purchase \| commitment	353
Boeing 737 MAX \| Forecast
Commitments and Contingencies [Line Items]
Number of aircraft expected to take delivery that are delayed \| aircraft		7
Bombardier CRJ550
Commitments and Contingencies [Line Items]
Number of aircraft committed to purchase \| commitment	8