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Financial Instruments - Fair Value Hedges (Details) - USD ($) $ in Millions | Mar. 31, 2019 | Dec. 31, 2018
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Loans payable and current portion of long-term debt |  |
Derivative Instruments and Hedging Activities Disclosures [Line Items] |  |
Carrying Amount of Hedged Liabilities | $ 1,237 | $ 0
Cumulative Amount of Fair Value Hedging Adjustment Increase (Decrease) Included in the Carrying Amount | (12) | 0
Long-Term Debt |  |
Derivative Instruments and Hedging Activities Disclosures [Line Items] |  |
Carrying Amount of Hedged Liabilities | 3,357 | 4,560
Cumulative Amount of Fair Value Hedging Adjustment Increase (Decrease) Included in the Carrying Amount | $ (37) | $ (82)

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- Definition Amount of liability hedged in fair value hedging relationship. + References Reference 1: http://www.xbrl.org/2003/role/disclosureRef -Publisher FASB -Name Accounting Standards Codification -Topic 815 -SubTopic 10 -Section 50 -Paragraph 4EE -Subparagraph (a) -URI http://asc.fasb.org/extlink&oid=109980867&loc=SL109999712-113959 + Details
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- Definition Amount of cumulative increase (decrease) in fair value of hedged liability in fair value hedge, attributable to hedged risk. + References Reference 1: http://www.xbrl.org/2003/role/disclosureRef -Publisher FASB -Name Accounting Standards Codification -Topic 815 -SubTopic 10 -Section 50 -Paragraph 4EE -Subparagraph (b) -URI http://asc.fasb.org/extlink&oid=109980867&loc=SL109999712-113959 + Details
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