Derivative Instruments and Hedging Activities (Fair Value Of Derivatives Not Designated As Hedging Instruments) (Details) - Not Designated As Hedging Instrument [Member] - USD ($) $ in Millions	Dec. 31, 2018	Dec. 31, 2017
Derivative [Line Items]
FX Contracts Assets	$ 175	$ 63
Commodity Contracts Assets	461	386
Total fair value of derivative assets not designated as hedging instruments	636	449
FX Contracts Liabilities	152	92
Commodity Contracts Liabilities	589	371
Total fair value of derivative liabilities not designated as hedging instruments.	$ 741	$ 463

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 all foreign currency derivative assets 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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