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Details about Accumulated Other Comprehensive Income Components (Parenthetical) (Detail) - USD ($) $ in Millions | 3 Months Ended | 6 Months Ended
--- | --- | ---
Jun. 30, 2015 | Jun. 30, 2015
United Airlines, Inc. |  |
Accumulated Other Comprehensive Income (Loss) [Line Items] |  |
Additional gains related to investments and other | $ 1 | $ 1

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- 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
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- Definition Amount of increase (decrease) in other comprehensive income, after tax, from changes classified as other. + References No definition available. + Details
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- Details
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