Derivative Financial Instruments and Risk Management (Details 4) - USD ($) $ in Millions	3 Months Ended	6 Months Ended
Jun. 30, 2019	Jun. 30, 2018	Jun. 30, 2019	Jun. 30, 2018
Derivative Instruments, Gain (Loss)
Interest expense	$ (200)	$ (190)	$ (401)	$ (364)
Other income (expense)	(6)	(5)	(10)	(12)
Designated derivatives \| Cash flow hedges
Derivative Instruments, Gain (Loss)
Amounts of Gains (Losses) Recognized in AOCI	(24)	128	(28)	95
Amounts of Gains (Losses) Reclassified from AOCI	3	124	17	99
Recognized in Earnings (Ineffective Portion)		0		0
Designated derivatives \| Cash flow hedges \| Interest rate contracts
Derivative Instruments, Gain (Loss)
Amounts of Gains (Losses) Recognized in AOCI	(34)	5	(60)	5
Designated derivatives \| Cash flow hedges \| Interest rate contracts \| Interest expense
Derivative Instruments, Gain (Loss)
Amounts of Gains (Losses) Reclassified from AOCI	0	0	1	1
Interest expense	(200)		(401)
Recognized in Earnings (Ineffective Portion)		0		0
Designated derivatives \| Cash flow hedges \| Cross currency contracts
Derivative Instruments, Gain (Loss)
Amounts of Gains (Losses) Recognized in AOCI	10	123	32	90
Designated derivatives \| Cash flow hedges \| Cross currency contracts \| Interest expense
Derivative Instruments, Gain (Loss)
Amounts of Gains (Losses) Reclassified from AOCI	7	5	14	8
Interest expense	(200)		(401)
Recognized in Earnings (Ineffective Portion)		0		0
Designated derivatives \| Cash flow hedges \| Cross currency contracts \| Other income (expense)
Derivative Instruments, Gain (Loss)
Amounts of Gains (Losses) Reclassified from AOCI	(4)	119	2	90
Other income (expense)	(6)		(10)
Recognized in Earnings (Ineffective Portion)		0		0
Undesignated derivatives
Derivative Instruments, Gain (Loss)
Gains (Losses) on Derivatives Not Designated as Hedging Instruments	(10)	23	(39)	16
Undesignated derivatives \| Foreign exchange contracts \| Other income (expense)
Derivative Instruments, Gain (Loss)
Gains (Losses) on Derivatives Not Designated as Hedging Instruments	(9)	18	(38)	11
Undesignated derivatives \| Cross currency contracts \| Other income (expense)
Derivative Instruments, Gain (Loss)
Gains (Losses) on Derivatives Not Designated as Hedging Instruments	$ (1)	$ 5	$ (1)	$ 5

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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