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Derivatives and Hedging - Interest Rate Management Risk Narrative (Details) - USD ($) $ in Millions | 3 Months Ended | 9 Months Ended
--- | --- | ---
Sep. 30, 2018 | Sep. 30, 2017 | Sep. 30, 2018 | Sep. 30, 2017
Derivative [Line Items] |  |  |  |
Estimated pretax losses currently included within Accumulated Other Comprehensive Loss that will be reclassified to earnings in next twelve months |  |  | $ 12 |
Not Designated as Hedging Instrument | Gross foreign exchange contracts |  |  |  |
Derivative [Line Items] |  |  |  |
Derivative gain (loss) | $ (4) | $ 8 | $ (15) | $ 9

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- Definition Represents the estimated net amount of unrealized gains (losses) on hedges at the reporting date expected to be reclassified to earnings within the next 12 months. + References No definition available. + Details
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- Definition Amount of increase (decrease) in the fair value of derivatives recognized in the income statement. + References Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef -Publisher FASB -Name Accounting Standards Codification -Topic 815 -SubTopic 10 -Section 50 -Paragraph 4A -Subparagraph (b)(1) -URI http://asc.fasb.org/extlink&oid=109980867&loc=SL5618551-113959 + 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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- Details
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