Financial Instruments (Unsettled Derivatives) (Details) lb in Millions, $ in Millions	Jun. 30, 2017 USD ($) lb	Dec. 31, 2016 USD ($)	Dec. 31, 2014 USD ($)
Derivatives, Fair Value [Line Items]
Derivative Asset, Fair Value, Gross Asset	$ 68	$ 146
Derivative Liability, Fair Value, Gross Liability	18	58
Derivative Asset, Fair Value, Gross Liability	4	14
Derivative Liability, Fair Value, Gross Asset	4	14
Derivative Asset	64	132
Derivative Liability	14	44
Trade accounts receivable [Member]
Derivatives, Fair Value [Line Items]
Derivative Asset	56	119
Derivative Liability	0	13
Other Current Assets
Derivatives, Fair Value [Line Items]
Derivative Asset	6	7
Derivative Liability	0	0
Accounts Payable and Accrued Liabilities
Derivatives, Fair Value [Line Items]
Derivative Asset	2	6
Derivative Liability	14	31
Commodity Contract [Member]
Derivatives, Fair Value [Line Items]
Derivative Asset, Fair Value, Gross Asset	6	9
Derivative Liability, Fair Value, Gross Liability	4	2
Derivative Asset, Fair Value, Gross Liability	0	2
Derivative Liability, Fair Value, Gross Asset	0	2
Derivative Asset	6	7
Derivative Liability	4	0
Embedded Derivative Financial Instruments [Member]
Derivatives, Fair Value [Line Items]
Derivative Asset, Fair Value, Gross Asset	62	137
Derivative Liability, Fair Value, Gross Liability	14	56
Derivative Asset, Fair Value, Gross Liability	4	12
Derivative Liability, Fair Value, Gross Asset	4	12
Derivative Asset	58	125
Derivative Liability	10	44
Designated as Hedging Instrument [Member] \| Commodity Contract [Member]
Derivatives, Fair Value [Line Items]
Derivative Asset, Fair Value, Gross Asset	$ 6	9
Derivative, Nonmonetary Notional Amount, Mass \| lb	49
Derivatives Not Designated as Hedging Instruments [Member] \| Embedded Derivative Financial Instruments [Member]
Derivatives, Fair Value [Line Items]
Derivative Asset, Fair Value, Gross Asset	$ 62	137
Derivative Liability, Fair Value, Gross Liability	$ 14	56
Derivatives Not Designated as Hedging Instruments [Member] \| Forward Contracts [Member]
Derivatives, Fair Value [Line Items]
Derivative, Nonmonetary Notional Amount, Mass \| lb	33
Commodity Contract [Member] \| Derivatives Not Designated as Hedging Instruments [Member]
Derivatives, Fair Value [Line Items]
Derivative Liability, Fair Value, Gross Liability	$ 18	58
Commodity Contract [Member] \| Derivatives Not Designated as Hedging Instruments [Member] \| Forward Contracts [Member]
Derivatives, Fair Value [Line Items]
Derivative Liability, Fair Value, Gross Liability	4		$ 0
Commodity Contract [Member] \| Derivatives Not Designated as Hedging Instruments [Member] \| FMC's Copper Futures and Swap Contracts [Member]
Derivatives, Fair Value [Line Items]
Derivative Liability, Fair Value, Gross Liability	$ 0	$ 2

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=51825145&loc=SL20226003-175313

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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.

+ References

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- Definition

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.

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- Definition

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.

+ References

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- Definition

Nominal mass used to calculate payments on a derivative instrument.

+ References

No definition available.

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- Definition

Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table.

+ References

No definition available.

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