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Summary of Roll Forward of Frequent Flyer Deferred Revenue (Detail) - Deferred Revenue for Miles in Loyalty Program - USD ($) $ in Millions | 3 Months Ended
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Mar. 31, 2018 | Mar. 31, 2017
Deferred Revenue Arrangement [Line Items] |  |
Total Frequent flyer deferred revenue-beginning balance | $ 4,783 | $ 4,889
Total miles awarded | 603 | 488
Travel miles redeemed (Passenger revenue) | (409) | (398)
Non-travel miles redeemed (Other operating revenue) | (40) | (39)
Total Frequent flyer deferred revenue-ending balance | $ 4,937 | $ 4,940

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- Definition Frequent flyer mileage miles awarded in period. + References No definition available. + Details
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- Definition Non-travel miles redemption, frequent flyer deferred revenue. + References No definition available. + Details
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- Definition Travel miles redemption, frequent flyer deferred revenue. + References No definition available. + Details
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- Definition Amount of deferred revenue as of balance sheet date. Deferred revenue represents collections of cash or other assets related to a revenue producing activity for which revenue has not yet been recognized. Generally, an entity records deferred revenue when it receives consideration from a customer before achieving certain criteria that must be met for revenue to be recognized in conformity with GAAP. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 605 -SubTopic 10 -Section S99 -Paragraph 1 -Subparagraph (SAB Topic 13.A.3) -URI http://asc.fasb.org/extlink&oid=65893310&loc=d3e214044-122780 Reference 2: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 605 -SubTopic 10 -Section S99 -Paragraph 1 -Subparagraph (SAB Topic 13.A.4(a).Q1) -URI http://asc.fasb.org/extlink&oid=65893310&loc=d3e214044-122780 + Details
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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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- Details
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