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SPECIAL ITEMS SPECIAL ITEMS (Details) - USD ($) $ in Millions | 12 Months Ended | 49 Months Ended
--- | --- | ---
Dec. 31, 2020 | Dec. 31, 2019 | Dec. 31, 2018 | Dec. 31, 2020
Merger-related Costs [Line Items] |  |  |  |
Special items - merger-related costs | $ 6 | $ 44 | $ 87 | $ 370
Special items—other | 0 | 0 | 45 |
Nondeductible expenses | 9 | 9 | 9 |
Virgin America Inc. [Member] |  |  |  |
Merger-related Costs [Line Items] |  |  |  |
Special items - merger-related costs | 6 | $ 44 | $ 87 |
Settlement Fee [Member] |  |  |  |
Merger-related Costs [Line Items] |  |  |  |
Special items—other | 20 |  |  |
One-time Bonus Payment [Member] |  |  |  |
Merger-related Costs [Line Items] |  |  |  |
Special items—other | $ 25 |  |  |

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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://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 805 -SubTopic 10 -Section 25 -Paragraph 23 -URI http://asc.fasb.org/extlink&oid=116868678&loc=d3e1043-128460 + Details
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- Definition Amount of the difference between reported income tax expense (benefit) and expected income tax expense (benefit) computed by applying the domestic federal statutory income tax rates to pretax income (loss) from continuing operations attributable to nondeductible expenses. + References Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef -Publisher FASB -Name Accounting Standards Codification -Topic 740 -SubTopic 10 -Section 50 -Paragraph 12 -URI http://asc.fasb.org/extlink&oid=84230637&loc=d3e32687-109319 + Details
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