XML 108 R78.htm IDEA: XBRL DOCUMENT
v3.6.0.2

Multi-Employer Plans (Detail) - Multiemployer Plans, Pension - IAM National Pension Plan - USD ($) $ in Millions | 12 Months Ended
--- | ---
Dec. 31, 2016 | Dec. 31, 2015 | Dec. 31, 2014
Multiemployer Plans [Line Items] |  |  |  |
EIN |  | 516031295 |  |
Pension Plan Number |  | 002 |  |
Pension Protection Act Zone Status (2016 and 2015) | [1] | Green |  |
FIP/RP Status Pending/Implemented |  | No |  |
United's Contributions |  |  | $ 395 |
Surcharge Imposed |  | No |  |
United Airlines, Inc. |  |  |  |
Multiemployer Plans [Line Items] |  |  |  |
United's Contributions |  | $ 41 | $ 40 | $ 39
[1] | At the date the financial statements were issued, Forms 5500 were not available for the plan year ending in 2016.

X
- Definition The Tax Identification Number (TIN), also known as an Employer Identification Number (EIN), is a unique 9-digit value assigned by the IRS. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher SEC -Name Regulation 12B -Number 240 -Section 12b -Subsection 1 + Details
Name: | dei_EntityTaxIdentificationNumber
Namespace Prefix: | dei_
Data Type: | dei:nineDigitItemType
Balance Type: | na
Period Type: | duration

X
- Definition Three digit plan number for a pension or postretirement benefit plan to which two or more unrelated employers contribute where assets contributed by one participating employer may be used to provide benefits to employees of other participating employers. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 715 -SubTopic 80 -Section 50 -Paragraph 5 -Subparagraph (b) -URI http://asc.fasb.org/extlink&oid=65877416&loc=SL14450657-114947 + Details
Name: | us-gaap_MultiemployerPlanNumber
Namespace Prefix: | us-gaap_
Data Type: | us-types:threeDigitItemType
Balance Type: | na
Period Type: | duration

X
- Definition Indicate the multiemployer plan's certified zone status as currently required by the Pension Protection Act of 2006 or a subsequent amendment thereof. The zone status categories are red (critical status), orange (seriously endangered), yellow (endangered), and green (none of the above). The acceptable values are "red", "orange", "yellow", "green", "other", and "NA". A multiemployer plan is a pension or postretirement benefit plan to which two or more unrelated employers contribute where assets contributed by one participating employer may be used to provide benefits to employees of other participating employers. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 715 -SubTopic 80 -Section 50 -Paragraph 5 -Subparagraph (c) -URI http://asc.fasb.org/extlink&oid=65877416&loc=SL14450657-114947 + Details
Name: | us-gaap_MultiemployerPlansCertifiedZoneStatus
Namespace Prefix: | us-gaap_
Data Type: | us-types:zoneStatusItemType
Balance Type: | na
Period Type: | duration

X
- Definition Indicate whether a funding improvement plan or rehabilitation plan has been implemented or is pending for a pension or postretirement benefit plan to which two or more unrelated employers contribute where assets contributed by one participating employer may be used to provide benefits to employees of other participating employers. The acceptable values are "no", "pending", "implemented", "other", and "NA". + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 715 -SubTopic 80 -Section 50 -Paragraph 5 -Subparagraph (f)(1) -URI http://asc.fasb.org/extlink&oid=65877416&loc=SL14450657-114947 + Details
Name: | us-gaap_MultiemployerPlansFundingImprovementPlanAndRehabilitationPlan
Namespace Prefix: | us-gaap_
Data Type: | us-types:fundingImprovementAndRehabilitationPlanItemType
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 No definition available. + Details
Name: | us-gaap_MultiemployerPlansLineItems
Namespace Prefix: | us-gaap_
Data Type: | xbrli:stringItemType
Balance Type: | na
Period Type: | duration

X
- Definition Amount of contributions made to the multiemployer plan by all employers who participate in the plan. A multiemployer plan is a pension or postretirement benefit plan to which two or more unrelated employers contribute where assets contributed by one participating employer may be used to provide benefits to employees of other participating employers. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 715 -SubTopic 80 -Section 50 -Paragraph 7 -Subparagraph (c) -URI http://asc.fasb.org/extlink&oid=65877416&loc=SL14450678-114947 + Details
Name: | us-gaap_MultiemployerPlansPlanContributions
Namespace Prefix: | us-gaap_
Data Type: | xbrli:monetaryItemType
Balance Type: | debit
Period Type: | duration

X
- Definition Indicate whether the employer paid a surcharge to the pension or postretirement benefit plan to which two or more unrelated employers contribute where assets contributed by one participating employer may be used to provide benefits to employees of other participating employers. The acceptable values are "no", "yes", and "NA". + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 715 -SubTopic 80 -Section 50 -Paragraph 5 -Subparagraph (f)(2) -URI http://asc.fasb.org/extlink&oid=65877416&loc=SL14450657-114947 + Details
Name: | us-gaap_MultiemployerPlansSurcharge
Namespace Prefix: | us-gaap_
Data Type: | us-types:surchargeItemType
Balance Type: | na
Period Type: | duration

X
- Details
Name: | us-gaap_MultiemployerPlanTypeAxis=us-gaap_MultiemployerPlansPensionMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

X
- Details
Name: | us-gaap_MultiemployerPlanNameAxis=ual_InternationalAssociationOfMachinistsNationalPensionPlanMember
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: |