Derivative Financial Instruments and Risk Management (Details 4) - USD ($) $ in Millions	12 Months Ended
Dec. 31, 2018	Dec. 31, 2017	Dec. 31, 2016
Designated derivatives \| Fair value hedges \| Interest rate contracts \| Other income (expense)
Derivative Instruments, Gain (Loss)
Gains (Losses) on Derivatives	$ 0	$ (2)	$ (12)
Gains (Losses) on Borrowings	0	2	11
Designated derivatives \| Cash flow hedges
Derivative Instruments, Gain (Loss)
Amounts of Gains (Losses) Recognized in AOCI (Effective Portion)	127	(77)	23
Amount of Gains (Losses) Reclassified from AOCI to Earnings (Effective Portion)	167	(72)	25
Recognized in Earnings (Ineffective Portion)	0	0	0
Designated derivatives \| Cash flow hedges \| Interest rate contracts \| Interest expense
Derivative Instruments, Gain (Loss)
Amounts of Gains (Losses) Recognized in AOCI (Effective Portion)	(38)	0	8
Amount of Gains (Losses) Reclassified from AOCI to Earnings (Effective Portion)	0	3	(3)
Recognized in Earnings (Ineffective Portion)	0	0	0
Designated derivatives \| Cash flow hedges \| Cross currency contracts \| Interest expense
Derivative Instruments, Gain (Loss)
Amount of Gains (Losses) Reclassified from AOCI to Earnings (Effective Portion)	19	6
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) Recognized in AOCI (Effective Portion)	165	(77)	15
Amount of Gains (Losses) Reclassified from AOCI to Earnings (Effective Portion)	148	(81)	28
Recognized in Earnings (Ineffective Portion)	0	0	0
Undesignated derivatives
Derivative Instruments, Gain (Loss)
Gains (Losses) on Derivatives Not Designated as Hedging Instruments	19	9	(24)
Undesignated derivatives \| Foreign exchange contracts \| Other income (expense)
Derivative Instruments, Gain (Loss)
Gains (Losses) on Derivatives Not Designated as Hedging Instruments	16	14	(10)
Undesignated derivatives \| Cross currency contracts \| Other income (expense)
Derivative Instruments, Gain (Loss)
Gains (Losses) on Derivatives Not Designated as Hedging Instruments	$ 3	$ (5)	$ (14)

Amount of gain (loss) from the increase (decrease) in fair value of derivative and nonderivative instruments designated as fair value hedging instruments recognized in the income statement.

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Amount of the increase (decrease) in fair value of the hedged item in a fair value hedge recognized in the income statement.

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

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The effective portion of net gain (loss) reclassified from accumulated other comprehensive income into income on derivative instruments designated and qualifying as hedging instruments.

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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 before tax of increase (decrease) in accumulated gain (loss) from derivative instruments designated and qualifying as the effective portion of cash flow hedges and an entity's share of an equity investee's increase (decrease) in deferred hedging gain (loss).

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