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ACQUISITION OF VIRGIN AMERICA INC. - NARRATIVE (Details) $ / shares in Units, $ in Millions |  | 3 Months Ended | 9 Months Ended
--- | --- | --- | ---
Dec. 14, 2016 USD ($) departures $ / shares | Sep. 30, 2017 USD ($) | Sep. 30, 2016 USD ($) | Sep. 30, 2017 USD ($) | Sep. 30, 2016 USD ($)
Business Acquisition [Line Items] |  |  |  |  |
Number of daily departures | departures | 1,200 |  |  |  |
Merger-related costs |  | $ 24 | $ 22 | $ 88 | $ 36
Virgin America Inc. |  |  |  |  |
Business Acquisition [Line Items] |  |  |  |  |
Percentage of common shares and voting interest acquired | 100.00% |  |  |  |
Consideration paid (usd per share) | $ / shares | $ 57 |  |  |  |
Cash consideration | $ 2,600 |  |  |  |
Merger-related costs |  | $ 24 | $ 22 | $ 88 | $ 36

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- Definition Percentage of voting equity interests acquired at the acquisition date in the business combination. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 805 -SubTopic 10 -Section 50 -Paragraph 2 -Subparagraph (c) -URI http://asc.fasb.org/extlink&oid=65885119&loc=d3e1392-128463 + Details
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- Definition This element represents acquisition-related costs incurred to effect a business combination which costs have been expensed during the period. Such costs include finder's fees; advisory, legal, accounting, valuation, and other professional or consulting fees; general administrative costs, including the costs of maintaining an internal acquisitions department; and may include costs of registering and issuing debt and equity securities. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 805 -SubTopic 10 -Section 25 -Paragraph 23 -URI http://asc.fasb.org/extlink&oid=73531572&loc=d3e1043-128460 + Details
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- Definition The cash outflow associated with the acquisition of business during the period. The cash portion only of the acquisition price. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Glossary Investing Activities -URI http://asc.fasb.org/extlink&oid=6516133 Reference 2: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 230 -SubTopic 10 -Section 45 -Paragraph 13 -Subparagraph (b) -URI http://asc.fasb.org/extlink&oid=66902209&loc=d3e3213-108585 + Details
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