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Details about Accumulated Other Comprehensive Income Components (Detail) - USD ($) $ in Millions | 3 Months Ended | 6 Months Ended
--- | --- | ---
Jun. 30, 2017 | Jun. 30, 2016 | Jun. 30, 2017 | Jun. 30, 2016
Salaries And Related Costs |  |  |  |  |
Accumulated Other Comprehensive Income (Loss) [Line Items] |  |  |  |  |
Amortization of unrecognized losses and prior service cost | [1] | $ 14 | $ 6 | $ 27 | $ 11
Fuel Oil Contract | Aircraft Fuel |  |  |  |  |
Accumulated Other Comprehensive Income (Loss) [Line Items] |  |  |  |  |
Reclassifications of losses into earnings |  |  | $ 35 | $ 2 | $ 173
[1] | This AOCI component is included in the computation of net periodic pension and other postretirement costs (see Note 5 of this report for additional information).

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