XML 106 R82.htm IDEA: XBRL DOCUMENT
v3.20.4

Commitments and Contingencies - Narrative (Details) | 12 Months Ended |  |
--- | --- | --- | ---
Dec. 31, 2020 USD ($) aircraftCommitment employee option $ / shares shares | Feb. 26, 2021 aircraft | Nov. 30, 2020 USD ($)
Commitments and Contingencies [Line Items] |  |  |
Cash collateral for a standby letter of credit | $ 217,000,000 |  |
Aggregate balance | $ 11,100,000,000 |  |
Number of call options to purchase regional jet aircraft | option | 303 |  |
United Airlines, Inc. |  |  |
Commitments and Contingencies [Line Items] |  |  |
Number of employees | employee | 74,400 |  |
Percentage of employees represented by various U.S. labor organizations | 84.00% |  |
United Airlines, Inc. | Surety Bonds |  |  |
Commitments and Contingencies [Line Items] |  |  |
Long-term line of credit | $ 380,000,000 |  |
Tax-Exempt Special Facilities Revenue Bonds |  |  |
Commitments and Contingencies [Line Items] |  |  |
Guarantor obligations, maximum exposure | 1,900,000,000 |  |
Tax-Exempt Special Facilities Revenue Bonds | Indirect Guarantee of Indebtedness |  |  |
Commitments and Contingencies [Line Items] |  |  |
Guarantor obligations, maximum exposure | 293,000,000 |  |
Contingent liabilities based on participation | 2,300,000,000 |  |
Aircraft Mortgage Debt |  |  |
Commitments and Contingencies [Line Items] |  |  |
Guarantor obligations, maximum exposure | 119,000,000 |  |
Floating Rate Debt |  |  |
Commitments and Contingencies [Line Items] |  |  |
Aggregate principal amount | $ 9,800,000,000 |  |
Debt instrument, remaining terms | 12 years |  |
Loans And Leases From Non U S Entities |  |  |
Commitments and Contingencies [Line Items] |  |  |
Debt instrument, remaining terms | 12 years |  |
Aggregate balance | $ 8,300,000,000 |  |
Kingsland |  |  |
Commitments and Contingencies [Line Items] |  |  |
Number of shares that may be put to United (in shares) | shares | 144,800,000 |  |
Number of ADRs that may be put to United (in shares) | shares | 18,100,000 |  |
Market price of common stock at fifth anniversary (in dollars per share) | $ / shares | $ 12 |  |
Aggregate maximum possible combined put payment and guarantee amount | $ 217,000,000 |  |
Kingsland | Standby Letter of Credit |  |  |
Commitments and Contingencies [Line Items] |  |  |
Cash collateral for a standby letter of credit |  |  | $ 217,000,000
Boeing 737-700 |  |  |
Commitments and Contingencies [Line Items] |  |  |
Number of firm commitments | aircraftCommitment | 11 |  |
Airbus A319 |  |  |
Commitments and Contingencies [Line Items] |  |  |
Number of firm commitments | aircraftCommitment | 17 |  |
Boeing 737 MAX |  |  |
Commitments and Contingencies [Line Items] |  |  |
Number of firm commitments | aircraftCommitment | 188 |  |
Boeing 737 MAX | Subsequent Event |  |  |
Commitments and Contingencies [Line Items] |  |  |
Scheduled aircraft deliveries for 2023 from new firm orders | aircraft |  | 25 |
Scheduled aircraft deliveries for 2022 from rescheduled deliveries | aircraft |  | 40 |
Scheduled aircraft deliveries for 2023 from rescheduled deliveries | aircraft |  | 5 |

X
- Definition Number of persons employed by the Entity + References No definition available. + Details
Name: | dei_EntityNumberOfEmployees
Namespace Prefix: | dei_
Data Type: | xbrli:decimalItemType
Balance Type: | na
Period Type: | instant

X
- Definition Commitments And Contingencies [Line Items] + References No definition available. + Details
Name: | ual_CommitmentsAndContingenciesLineItems
Namespace Prefix: | ual_
Data Type: | xbrli:stringItemType
Balance Type: | na
Period Type: | duration

X
- Definition Years remaining on debt instruments. + References No definition available. + Details
Name: | ual_DebtInstrumentRemainingTerms
Namespace Prefix: | ual_
Data Type: | xbrli:durationItemType
Balance Type: | na
Period Type: | duration

X
- Definition Loans Receivable, Aggregate Maximum Payment And Guarantee Amount + References No definition available. + Details
Name: | ual_LoansReceivableAggregateMaximumPaymentAndGuaranteeAmount
Namespace Prefix: | ual_
Data Type: | xbrli:monetaryItemType
Balance Type: | debit
Period Type: | instant

X
- Definition Loans Receivable, Agreement, Put Option, Deposit Receipts + References No definition available. + Details
Name: | ual_LoansReceivableAgreementPutOptionDepositReceipts
Namespace Prefix: | ual_
Data Type: | xbrli:sharesItemType
Balance Type: | na
Period Type: | instant

X
- Definition Loans Receivable, Agreement, Put Options + References No definition available. + Details
Name: | ual_LoansReceivableAgreementPutOptions
Namespace Prefix: | ual_
Data Type: | xbrli:sharesItemType
Balance Type: | na
Period Type: | instant

X
- Definition Loans Receivable, Guarantee And Payout Share Price At Fifth Anniversary + References No definition available. + Details
Name: | ual_LoansReceivableGuaranteeAndPayoutSharePriceAtFifthAnniversary
Namespace Prefix: | ual_
Data Type: | num:perShareItemType
Balance Type: | na
Period Type: | instant

X
- Definition Number Of Aircrafts Expected To Take Delivery, New Purchases, Year Three + References No definition available. + Details
Name: | ual_NumberOfAircraftsExpectedToTakeDeliveryNewPurchasesYearThree
Namespace Prefix: | ual_
Data Type: | xbrli:integerItemType
Balance Type: | na
Period Type: | instant

X
- Definition Number Of Aircrafts Expected To Take Delivery, Rescheduled Deliveries, Year Three + References No definition available. + Details
Name: | ual_NumberOfAircraftsExpectedToTakeDeliveryRescheduledDeliveriesYearThree
Namespace Prefix: | ual_
Data Type: | xbrli:integerItemType
Balance Type: | na
Period Type: | instant

X
- Definition Number Of Aircrafts Expected To Take Delivery, Rescheduled Deliveries, Year Two + References No definition available. + Details
Name: | ual_NumberOfAircraftsExpectedToTakeDeliveryRescheduledDeliveriesYearTwo
Namespace Prefix: | ual_
Data Type: | xbrli:integerItemType
Balance Type: | na
Period Type: | instant

X
- Definition Number of Call Options To Purchase Regional Jet Aircraft + References No definition available. + Details
Name: | ual_NumberOfCallOptionsToPurchaseRegionalJetAircraft
Namespace Prefix: | ual_
Data Type: | xbrli:integerItemType
Balance Type: | na
Period Type: | duration

X
- Definition Percentage of employees represented by labor organizations + References No definition available. + Details
Name: | ual_PercentageOfEmployeesRepresentedByLaborOrganizations
Namespace Prefix: | ual_
Data Type: | num:percentItemType
Balance Type: | na
Period Type: | duration

X
- Definition Carrying amount as of the balance sheet date of cash collateral held for borrowed securities, for which the cash is restricted as to withdrawal or usage. + References Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 942 -SubTopic 210 -Section S99 -Paragraph 1 -Subparagraph (SX 210.9-03.1) -URI http://asc.fasb.org/extlink&oid=120398452&loc=d3e534808-122878 Reference 2: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 944 -SubTopic 210 -Section S99 -Paragraph 1 -Subparagraph (SX 210.7-03.(a),2) -URI http://asc.fasb.org/extlink&oid=120400017&loc=d3e572229-122910 + Details
Name: | us-gaap_CashCollateralForBorrowedSecurities
Namespace Prefix: | us-gaap_
Data Type: | xbrli:monetaryItemType
Balance Type: | debit
Period Type: | instant

X
- Definition Amount of contractual obligation, including but not limited to, long-term debt, capital lease obligations, operating lease obligations, purchase obligations, and other commitments. + References No definition available. + Details
Name: | us-gaap_ContractualObligation
Namespace Prefix: | us-gaap_
Data Type: | xbrli:monetaryItemType
Balance Type: | credit
Period Type: | instant

X
- Definition Face (par) amount of debt instrument at time of issuance. + References Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 835 -SubTopic 30 -Section 45 -Paragraph 2 -URI http://asc.fasb.org/extlink&oid=119993939&loc=d3e28551-108399 Reference 2: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 835 -SubTopic 30 -Section 55 -Paragraph 8 -URI http://asc.fasb.org/extlink&oid=114775985&loc=d3e28878-108400 + Details
Name: | us-gaap_DebtInstrumentFaceAmount
Namespace Prefix: | us-gaap_
Data Type: | xbrli:monetaryItemType
Balance Type: | credit
Period Type: | instant

X
- Definition The current carrying amount of the liability for the freestanding or embedded guarantor's obligations under the guarantee or each group of similar guarantees. + References Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 460 -SubTopic 10 -Section 50 -Paragraph 4 -Subparagraph (c) -URI http://asc.fasb.org/extlink&oid=121555522&loc=d3e12069-110248 + Details
Name: | us-gaap_GuaranteeObligationsCurrentCarryingValue
Namespace Prefix: | us-gaap_
Data Type: | xbrli:monetaryItemType
Balance Type: | credit
Period Type: | instant

X
- Definition 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. + References Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 460 -SubTopic 10 -Section 50 -Paragraph 4 -Subparagraph (b)(1) -URI http://asc.fasb.org/extlink&oid=121555522&loc=d3e12069-110248 + Details
Name: | us-gaap_GuaranteeObligationsMaximumExposure
Namespace Prefix: | us-gaap_
Data Type: | xbrli:monetaryItemType
Balance Type: | credit
Period Type: | instant

X
- Definition The carrying value as of the balance sheet date of the current and noncurrent portions of long-term obligations drawn from a line of credit, which is a bank's commitment to make loans up to a specific amount. Examples of items that might be included in the application of this element may consist of letters of credit, standby letters of credit, and revolving credit arrangements, under which borrowings can be made up to a maximum amount as of any point in time conditional on satisfaction of specified terms before, as of and after the date of drawdowns on the line. Includes short-term obligations that would normally be classified as current liabilities but for which (a) postbalance sheet date issuance of a long term obligation to refinance the short term obligation on a long term basis, or (b) the enterprise has entered into a financing agreement that clearly permits the enterprise to refinance the short-term obligation on a long term basis and the following conditions are met (1) the agreement does not expire within 1 year and is not cancelable by the lender except for violation of an objectively determinable provision, (2) no violation exists at the BS date, and (3) the lender has entered into the financing agreement is expected to be financially capable of honoring the agreement. + References Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 210 -SubTopic 10 -Section S99 -Paragraph 1 -Subparagraph (SX 210.5-02(22)) -URI http://asc.fasb.org/extlink&oid=120391452&loc=d3e13212-122682 Reference 2: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 942 -SubTopic 210 -Section S99 -Paragraph 1 -Subparagraph (SX 210.9-03(16)) -URI http://asc.fasb.org/extlink&oid=120398452&loc=d3e534808-122878 Reference 3: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 944 -SubTopic 210 -Section S99 -Paragraph 1 -Subparagraph (SX 210.7-03(16)) -URI http://asc.fasb.org/extlink&oid=120400017&loc=d3e572229-122910 + Details
Name: | us-gaap_LineOfCredit
Namespace Prefix: | us-gaap_
Data Type: | xbrli:monetaryItemType
Balance Type: | credit
Period Type: | instant

X
- Definition 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. + References No definition available. + Details
Name: | us-gaap_UnrecordedUnconditionalPurchaseObligationMinimumQuantityRequired
Namespace Prefix: | us-gaap_
Data Type: | xbrli:decimalItemType
Balance Type: | na
Period Type: | instant

X
- Details
Name: | dei_LegalEntityAxis=ual_UnitedAirLinesIncMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

X
- Details
Name: | us-gaap_GuaranteeObligationsByNatureAxis=us-gaap_SuretyBondMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

X
- Details
Name: | us-gaap_DebtInstrumentAxis=ual_TaxExemptBondsMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

X
- Details
Name: | us-gaap_GuaranteeObligationsByNatureAxis=us-gaap_IndirectGuaranteeOfIndebtednessMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

X
- Details
Name: | us-gaap_DebtInstrumentAxis=ual_AircraftMortgageDebtMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

X
- Details
Name: | us-gaap_DebtInstrumentAxis=ual_FloatingRateDebtMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

X
- Details
Name: | us-gaap_DebtInstrumentAxis=ual_LoansAndLeasesFromNonUSEntitiesMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

X
- Details
Name: | srt_CounterpartyNameAxis=ual_KingslandHoldingsLimitedMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

X
- Details
Name: | us-gaap_LossContingenciesByNatureOfContingencyAxis=us-gaap_StandbyLettersOfCreditMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

X
- Details
Name: | srt_AircraftTypeAxis=ual_Boeing737700Member
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

X
- Details
Name: | srt_AircraftTypeAxis=ual_AirbusA319sMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

X
- Details
Name: | srt_AircraftTypeAxis=ual_Boeing737MaxMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

X
- Details
Name: | us-gaap_SubsequentEventTypeAxis=us-gaap_SubsequentEventMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |