Derivative Instruments and Hedging Activities (Fair Value Of Derivatives Not Designated As Hedging Instruments) (Details) - Not Designated As Hedging Instrument [Member] - USD ($) $ in Millions	Sep. 30, 2020	Dec. 31, 2019
Derivative [Line Items]
FX Contracts Assets	$ 276	$ 125
Embedded Derivative, Fair Value of Embedded Derivative Asset	0	0
Commodity Contracts Assets	1,474	478
Total fair value of derivative assets not designated as hedging instruments	1,750	603
FX Contracts Liabilities	547	120
Commodity Contracts Liabilities	1,388	574
Embedded Derivative, Fair Value of Embedded Derivative Liability	32	0
Total fair value of derivative liabilities not designated as hedging instruments.	$ 1,967	$ 694

Fair value, before effects of master netting arrangements, of a financial asset or other contract with one or more underlyings, notional amount or payment provision or both, and the contract can be net settled by means outside the contract or delivery of an asset. Includes assets elected not to be offset. Excludes assets not subject to a master netting arrangement.

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Fair value, before effects of master netting arrangements, of a financial liability or contract with one or more underlyings, notional amount or payment provision or both, and the contract can be net settled by means outside the contract or delivery of an asset. Includes liabilities elected not to be offset. Excludes liabilities not subject to a master netting arrangement.

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Fair value as of the balance sheet date of the embedded derivative or group of embedded derivatives classified as an asset.

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Fair value as of the balance sheet date of all foreign currency derivative assets not designated as hedging instruments.

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Fair value as of the balance sheet date of all foreign currency derivative liabilities not designated as hedging instruments.

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Fair value as of the balance sheet date of all price risk derivative assets not designated as hedging instruments.

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