Financial and Derivative Instruments (Details 2) - USD ($) $ in Millions	Mar. 31, 2018	Dec. 31, 2017
Offsetting Assets [Abstract]
Derivative Assets, Gross Amount Recognized	$ 1,180	$ 1,169
Derivative Assets, Gross Amounts Offset	1,173	1,147
Derivative Assets, Net Amounts Presented	7	22
Derivative Assets, Gross Amounts Not Offset	0	0
Derivative Assets, Net Amounts Presented	7	22
Offsetting Liabilities [Abstract]
Derivative Liabilities, Gross Amount Recognized	1,268	1,271
Derivative Liabilities, Gross Amounts Offset	1,173	1,147
Derivative Liabilities, Net Amounts Presented	95	124
Derivative Liabilities, Gross Amounts Not Offset	0	0
Derivative Liabilities, Net Amounts Presented	$ 95	$ 124

Fair value of liability associated with 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.

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 210
-SubTopic 20
-Section 55
-Paragraph 8
-URI http://asc.fasb.org/extlink&oid=82849420&loc=SL20226003-175313

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-Publisher FASB
-Name Accounting Standards Codification
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-Section 50
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Fair value, after effects of master netting arrangements, deduction of assets not subject to a master netting arrangement and elected not to be offset, of 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, offset against an obligation to return collateral.

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Fair value of 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, not subject to a master netting arrangement, deducted from derivative assets.

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Fair value, after the 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 not subject to a master netting arrangement and not elected to be offset.

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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.

+ References

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Fair value, after the 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 not subject to a master netting arrangement and not elected to be offset.

+ References

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Fair value of asset associated with 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.

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Fair value, after effects of master netting arrangements, deduction of liabilities not subject to a master netting arrangement and elected not to be offset, of 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, offset against the right to receive collateral.

+ References

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