Derivative Financial Instruments and Risk Management (Details 4) - USD ($) $ in Millions	3 Months Ended
Mar. 31, 2020	Mar. 31, 2019
Derivative Instruments, Gain (Loss)
Interest Expense	$ 175	$ 201
Other income (expense)	(10)	(4)
Designated derivatives \| Cash flow hedges
Derivative Instruments, Gain (Loss)
Amount of Gains (Losses) Recognized in AOCI	86	(4)
Amount of Gains (Losses) Reclassified from AOCI	77	14
Designated derivatives \| Cash flow hedges \| Interest rate contracts
Derivative Instruments, Gain (Loss)
Amount of Gains (Losses) Recognized in AOCI	(15)	(26)
Designated derivatives \| Cash flow hedges \| Interest rate contracts \| Interest expense
Derivative Instruments, Gain (Loss)
Amount of Gains (Losses) Reclassified from AOCI	(5)	1
Interest Expense	175	201
Designated derivatives \| Cash flow hedges \| Cross currency contracts
Derivative Instruments, Gain (Loss)
Amount of Gains (Losses) Recognized in AOCI	101	22
Designated derivatives \| Cash flow hedges \| Cross currency contracts \| Interest expense
Derivative Instruments, Gain (Loss)
Amount of Gains (Losses) Reclassified from AOCI	11	7
Interest Expense	175	201
Designated derivatives \| Cash flow hedges \| Cross currency contracts \| Other income (expense)
Derivative Instruments, Gain (Loss)
Amount of Gains (Losses) Reclassified from AOCI	71	6
Other income (expense)	(10)	(4)
Undesignated derivatives
Derivative Instruments, Gain (Loss)
Gains (Losses) on Derivatives Not Designated as Hedging Instruments	108	(29)
Undesignated derivatives \| Foreign exchange contracts \| Other income (expense)
Derivative Instruments, Gain (Loss)
Gains (Losses) on Derivatives Not Designated as Hedging Instruments	99	(29)
Undesignated derivatives \| Cross currency contracts \| Other income (expense)
Derivative Instruments, Gain (Loss)
Gains (Losses) on Derivatives Not Designated as Hedging Instruments	$ 9	$ 0

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

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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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Amount, before tax, of reclassification of gain (loss) from accumulated other comprehensive income (AOCI) for derivative instrument designated and qualifying as cash flow hedge included in assessment of hedge effectiveness.

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