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Financial Instruments - Fair Value Hedges (Details) - USD ($) $ in Millions	Jun. 30, 2019	Dec. 31, 2018
Loans payable and current portion of long-term debt
Derivative Instruments and Hedging Activities Disclosures [Line Items]
Carrying Amount of Hedged Liabilities	$ 1,244	$ 0
Cumulative Amount of Fair Value Hedging Adjustment Increase (Decrease) Included in the Carrying Amount	(6)	0
Long-Term Debt
Derivative Instruments and Hedging Activities Disclosures [Line Items]
Carrying Amount of Hedged Liabilities	3,406	4,560
Cumulative Amount of Fair Value Hedging Adjustment Increase (Decrease) Included in the Carrying Amount	$ 11	$ (82)

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+ References

No definition available.

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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

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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

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