XML 108 R74.htm IDEA: XBRL DOCUMENT
v3.25.0.1

PENSION, POSTRETIREMENT AND OTHER EMPLOYEE BENEFIT PLANS - Participation in the IAM National Pension Plan (Details) - IAM National Pension Plan - USD ($) $ in Millions |  | 12 Months Ended |
--- | --- | --- | ---
Jan. 01, 2022 | Dec. 31, 2024 | Dec. 31, 2023 | Dec. 31, 2022 | Jan. 01, 2023
Multiemployer Plans [Line Items] |  |  |  |  |
Multi-employer plan contributions |  |  | $ 570 |  |
Pension Benefits |  |  |  |  |
Multiemployer Plans [Line Items] |  |  |  |  |
Plan length | 10 years |  |  |  |
Additional contribution as a percentage of the hourly contribution rate | 2.50% |  |  |  |
Surcharge imposed |  | No |  |  |
Pension Benefits | United Airlines, Inc. |  |  |  |  |
Multiemployer Plans [Line Items] |  |  |  |  |
Funded percentage |  |  |  |  | 86.50%
Contributions |  | $ 95 | $ 87 | $ 75 |

X
- Definition Multiemployer Plan, Additional Contribution Rate In Excess Of The Hourly Contribution Rate + References No definition available. + Details
Name: | ual_MultiemployerPlanAdditionalContributionRateInExcessOfTheHourlyContributionRate
Namespace Prefix: | ual_
Data Type: | dtr-types1:percentItemType
Balance Type: | na
Period Type: | duration

X
- Definition Multiemployer Plan, Rehabilitation Plan Term + References No definition available. + Details
Name: | ual_MultiemployerPlanRehabilitationPlanTerm
Namespace Prefix: | ual_
Data Type: | xbrli:durationItemType
Balance Type: | na
Period Type: | duration

X
- Definition Percentage of plan assets to benefit obligation of defined benefit plan. + References No definition available. + Details
Name: | us-gaap_DefinedBenefitPlanFundedPercentage
Namespace Prefix: | us-gaap_
Data Type: | dtr-types:percentItemType
Balance Type: | na
Period Type: | instant

X
- Definition Amount of cost for employer contribution to multiemployer plan. Multiemployer plan includes, but is not limited to, pension plan determined to be individually significant and insignificant and other postretirement benefit plan. + References Reference 1: http://www.xbrl.org/2003/role/exampleRef -Topic 715 -SubTopic 80 -Name Accounting Standards Codification -Section 55 -Paragraph 8 -Publisher FASB -URI https://asc.fasb.org/1943274/2147480547/715-80-55-8 Reference 2: http://www.xbrl.org/2003/role/disclosureRef -Topic 715 -SubTopic 80 -Name Accounting Standards Codification -Section 35 -Paragraph 1 -Publisher FASB -URI https://asc.fasb.org/1943274/2147480606/715-80-35-1 Reference 3: http://www.xbrl.org/2003/role/disclosureRef -Topic 715 -SubTopic 80 -Name Accounting Standards Codification -Section 50 -Paragraph 11 -Publisher FASB -URI https://asc.fasb.org/1943274/2147480576/715-80-50-11 Reference 4: http://www.xbrl.org/2003/role/disclosureRef -Topic 715 -SubTopic 80 -Name Accounting Standards Codification -Section 50 -Paragraph 9 -Subparagraph (b) -Publisher FASB -URI https://asc.fasb.org/1943274/2147480576/715-80-50-9 + Details
Name: | us-gaap_MultiemployerPlanEmployerContributionCost
Namespace Prefix: | us-gaap_
Data Type: | xbrli:monetaryItemType
Balance Type: | debit
Period Type: | duration

X
- Definition Amount of contribution received by multiemployer pension plan from all employers participating in multiemployer pension plan determined to be individually significant. + References Reference 1: http://www.xbrl.org/2003/role/exampleRef -Topic 715 -SubTopic 80 -Name Accounting Standards Codification -Section 55 -Paragraph 8 -Publisher FASB -URI https://asc.fasb.org/1943274/2147480547/715-80-55-8 Reference 2: http://www.xbrl.org/2003/role/disclosureRef -Topic 715 -SubTopic 80 -Name Accounting Standards Codification -Section 50 -Paragraph 7 -Subparagraph (c) -Publisher FASB -URI https://asc.fasb.org/1943274/2147480576/715-80-50-7 + Details
Name: | us-gaap_MultiemployerPlanPensionSignificantPlanContribution
Namespace Prefix: | us-gaap_
Data Type: | xbrli:monetaryItemType
Balance Type: | debit
Period Type: | duration

X
- Definition Indicates whether employer paid surcharge to multiemployer pension plan determined to be individually significant. Acceptable values are "No", "Yes", and "NA". + References Reference 1: http://www.xbrl.org/2003/role/exampleRef -Topic 715 -SubTopic 80 -Name Accounting Standards Codification -Section 55 -Paragraph 8 -Publisher FASB -URI https://asc.fasb.org/1943274/2147480547/715-80-55-8 Reference 2: http://www.xbrl.org/2003/role/disclosureRef -Topic 715 -SubTopic 80 -Name Accounting Standards Codification -Section 50 -Paragraph 5 -Subparagraph (f)(2) -Publisher FASB -URI https://asc.fasb.org/1943274/2147480576/715-80-50-5 + Details
Name: | us-gaap_MultiemployerPlanPensionSignificantSurchargeFixedList
Namespace Prefix: | us-gaap_
Data Type: | us-types:surchargeItemType
Balance Type: | na
Period Type: | duration

X
- Definition Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table. + References Reference 1: http://www.xbrl.org/2003/role/exampleRef -Topic 715 -SubTopic 80 -Name Accounting Standards Codification -Section 55 -Paragraph 8 -Publisher FASB -URI https://asc.fasb.org/1943274/2147480547/715-80-55-8 Reference 2: http://www.xbrl.org/2003/role/exampleRef -Topic 715 -SubTopic 80 -Name Accounting Standards Codification -Section 50 -Paragraph 6 -Subparagraph (b) -Publisher FASB -URI https://asc.fasb.org/1943274/2147480576/715-80-50-6 Reference 3: http://www.xbrl.org/2003/role/exampleRef -Topic 715 -SubTopic 80 -Name Accounting Standards Codification -Section 50 -Paragraph 6 -Subparagraph (c) -Publisher FASB -URI https://asc.fasb.org/1943274/2147480576/715-80-50-6 Reference 4: http://www.xbrl.org/2003/role/exampleRef -Topic 715 -SubTopic 80 -Name Accounting Standards Codification -Section 50 -Paragraph 11 -Subparagraph (a) -Publisher FASB -URI https://asc.fasb.org/1943274/2147480576/715-80-50-11 Reference 5: http://www.xbrl.org/2003/role/exampleRef -Topic 715 -SubTopic 80 -Name Accounting Standards Codification -Section 50 -Paragraph 11 -Subparagraph (c) -Publisher FASB -URI https://asc.fasb.org/1943274/2147480576/715-80-50-11 Reference 6: http://www.xbrl.org/2003/role/exampleRef -Topic 715 -SubTopic 80 -Name Accounting Standards Codification -Section 50 -Paragraph 11 -Subparagraph (b) -Publisher FASB -URI https://asc.fasb.org/1943274/2147480576/715-80-50-11 Reference 7: http://www.xbrl.org/2003/role/disclosureRef -Topic 715 -SubTopic 80 -Name Accounting Standards Codification -Section 35 -Paragraph 1 -Publisher FASB -URI https://asc.fasb.org/1943274/2147480606/715-80-35-1 Reference 8: http://www.xbrl.org/2003/role/disclosureRef -Topic 715 -SubTopic 80 -Name Accounting Standards Codification -Section 50 -Paragraph 11 -Publisher FASB -URI https://asc.fasb.org/1943274/2147480576/715-80-50-11 Reference 9: http://www.xbrl.org/2003/role/disclosureRef -Topic 715 -SubTopic 80 -Name Accounting Standards Codification -Section 50 -Paragraph 5 -Subparagraph (a) -Publisher FASB -URI https://asc.fasb.org/1943274/2147480576/715-80-50-5 Reference 10: http://www.xbrl.org/2003/role/disclosureRef -Topic 715 -SubTopic 80 -Name Accounting Standards Codification -Section 50 -Paragraph 5 -Subparagraph (b) -Publisher FASB -URI https://asc.fasb.org/1943274/2147480576/715-80-50-5 Reference 11: http://www.xbrl.org/2003/role/disclosureRef -Topic 715 -SubTopic 80 -Name Accounting Standards Codification -Section 50 -Paragraph 5 -Subparagraph (c) -Publisher FASB -URI https://asc.fasb.org/1943274/2147480576/715-80-50-5 Reference 12: http://www.xbrl.org/2003/role/disclosureRef -Topic 715 -SubTopic 80 -Name Accounting Standards Codification -Section 50 -Paragraph 5 -Subparagraph (d) -Publisher FASB -URI https://asc.fasb.org/1943274/2147480576/715-80-50-5 Reference 13: http://www.xbrl.org/2003/role/disclosureRef -Topic 715 -SubTopic 80 -Name Accounting Standards Codification -Section 50 -Paragraph 5 -Subparagraph (e)(1) -Publisher FASB -URI https://asc.fasb.org/1943274/2147480576/715-80-50-5 Reference 14: http://www.xbrl.org/2003/role/disclosureRef -Topic 715 -SubTopic 80 -Name Accounting Standards Codification -Section 50 -Paragraph 5 -Subparagraph (e)(2) -Publisher FASB -URI https://asc.fasb.org/1943274/2147480576/715-80-50-5 Reference 15: http://www.xbrl.org/2003/role/disclosureRef -Topic 715 -SubTopic 80 -Name Accounting Standards Codification -Section 50 -Paragraph 5 -Subparagraph (f)(1) -Publisher FASB -URI https://asc.fasb.org/1943274/2147480576/715-80-50-5 Reference 16: http://www.xbrl.org/2003/role/disclosureRef -Topic 715 -SubTopic 80 -Name Accounting Standards Codification -Section 50 -Paragraph 5 -Subparagraph (f)(2) -Publisher FASB -URI https://asc.fasb.org/1943274/2147480576/715-80-50-5 Reference 17: http://www.xbrl.org/2003/role/disclosureRef -Topic 715 -SubTopic 80 -Name Accounting Standards Codification -Section 50 -Paragraph 5 -Subparagraph (f)(3) -Publisher FASB -URI https://asc.fasb.org/1943274/2147480576/715-80-50-5 Reference 18: http://www.xbrl.org/2003/role/disclosureRef -Topic 715 -SubTopic 80 -Name Accounting Standards Codification -Section 50 -Paragraph 9 -Subparagraph (b) -Publisher FASB -URI https://asc.fasb.org/1943274/2147480576/715-80-50-9 Reference 19: http://www.xbrl.org/2003/role/exampleRef -Topic 715 -SubTopic 80 -Name Accounting Standards Codification -Section 50 -Paragraph 6 -Subparagraph (a) -Publisher FASB -URI https://asc.fasb.org/1943274/2147480576/715-80-50-6 + Details
Name: | us-gaap_MultiemployerPlansLineItems
Namespace Prefix: | us-gaap_
Data Type: | xbrli:stringItemType
Balance Type: | na
Period Type: | duration

X
- Details
Name: | us-gaap_RetirementPlanNameAxis=ual_InternationalAssociationOfMachinistsNationalPensionPlanMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

X
- Details
Name: | us-gaap_RetirementPlanTypeAxis=us-gaap_PensionPlansDefinedBenefitMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

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