Fair value portion of debt instrument payable, including, but not limited to, notes payable and loans payable.

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Nominal or face amount used to calculate payment on derivative.

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Amount of investment in equity security without readily determinable fair value.

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Amount of unrealized gain (loss) on investment in marketable security.

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Including the current and noncurrent portions, carrying value as of the balance sheet date of Notes with the highest claim on the assets of the issuer in case of bankruptcy or liquidation (with maturities initially due after one year or beyond the operating cycle if longer). Senior note holders are paid off in full before any payments are made to junior note holders.

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Financial Instruments and Fair Value Measurements (Narrative) (Details) - USD ($) $ in Millions	3 Months Ended
	Mar. 31, 2020	Mar. 31, 2019	Dec. 31, 2019
Derivative [Line Items]
Carrying value of senior debt	$ 17,980		$ 17,980
Investments without readily determinable fair value	114		113
Proceeds from sale of marketable securities	146
Gain on marketable securities	$ 0	$ 38
Cash Flow Hedging [Member] \| Foreign exchange contract [Member]
Derivative [Line Items]
Maximum derivative contract term	24 months
Notional amount of derivative	$ 1,370		1,440
Cash Flow Hedging [Member] \| Foreign exchange contract [Member] \| Future Production Costs [Member]
Derivative [Line Items]
Notional amount of derivative	713		833
Cash Flow Hedging [Member] \| Foreign exchange contract [Member] \| Other Foreign Currency [Member]
Derivative [Line Items]
Notional amount of derivative	658		606
Senior Debt [Member]
Derivative [Line Items]
Fair value of senior debt	$ 18,200		$ 20,600