Derivative Financial Instruments and Risk Management (Details 4) - USD ($) $ in Millions	3 Months Ended	9 Months Ended
Sep. 30, 2019	Sep. 30, 2018	Sep. 30, 2019	Sep. 30, 2018
Derivative Instruments, Gain (Loss)
Interest expense	$ (198)	$ (194)	$ (599)	$ (558)
Other income (expense)	(4)	(3)	(14)	(15)
Designated derivatives \| Cash flow hedges
Derivative Instruments, Gain (Loss)
Amount of Gains (Losses) Recognized in AOCI	88	56	60	151
Amount of Gains (Losses) Reclassified from AOCI	95	56	112	155
Recognized in Earnings (Ineffective Portion)		0		0
Designated derivatives \| Cash flow hedges \| Interest rate contracts
Derivative Instruments, Gain (Loss)
Amount of Gains (Losses) Recognized in AOCI	(12)	3	(72)	8
Designated derivatives \| Cash flow hedges \| Interest rate contracts \| Interest expense
Derivative Instruments, Gain (Loss)
Amount of Gains (Losses) Reclassified from AOCI	(3)	0	(2)	1
Interest expense	(198)		(599)
Recognized in Earnings (Ineffective Portion)		0		0
Designated derivatives \| Cash flow hedges \| Cross currency contracts
Derivative Instruments, Gain (Loss)
Amount of Gains (Losses) Recognized in AOCI	100	53	132	143
Designated derivatives \| Cash flow hedges \| Cross currency contracts \| Interest expense
Derivative Instruments, Gain (Loss)
Amount of Gains (Losses) Reclassified from AOCI	9	5	23	13
Interest expense	(198)		(599)
Recognized in Earnings (Ineffective Portion)		0		0
Designated derivatives \| Cash flow hedges \| Cross currency contracts \| Other income (expense)
Derivative Instruments, Gain (Loss)
Amount of Gains (Losses) Reclassified from AOCI	89	51	91	141
Other income (expense)	(4)		(14)
Recognized in Earnings (Ineffective Portion)		0		0
Undesignated derivatives
Derivative Instruments, Gain (Loss)
Gains (Losses) on Derivatives Not Designated as Hedging Instruments	15	13	(24)	29
Undesignated derivatives \| Foreign exchange contracts \| Other income (expense)
Derivative Instruments, Gain (Loss)
Gains (Losses) on Derivatives Not Designated as Hedging Instruments	12	12	(26)	23
Undesignated derivatives \| Cross currency contracts \| Other income (expense)
Derivative Instruments, Gain (Loss)
Gains (Losses) on Derivatives Not Designated as Hedging Instruments	$ 3	$ 1	$ 2	$ 6

Amount of increase (decrease) in the fair value of derivatives recognized in the income statement.

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The portion of gains and losses (net) on derivative instruments designated and qualifying as hedging instruments representing (a) the amount of the hedge ineffectiveness and (b) the amount, if any, excluded from the assessment of hedge effectiveness.

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Amount of the cost of borrowed funds accounted for as interest expense.

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Amount, before tax and reclassification, of gain (loss) from derivative instrument designated and qualifying cash flow hedge included in assessment of hedge effectiveness.

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