Financial Instruments (Unaudited) Unsettled Derivatives (Details) (USD $) In Millions, unless otherwise specified	Mar. 31, 2015		Dec. 31, 2014
Derivatives, Fair Value [Line Items]
Derivative Asset	$ 307		$ 330
Derivative Liability	51		99
Paid to brokers associated with margin requirements	5		10
Trade Accounts Receivable [Member]
Derivatives, Fair Value [Line Items]
Derivative Asset	32		5
Derivative Liability	22		56
Other Current Assets [Member]
Derivatives, Fair Value [Line Items]
Derivative Asset	270		316
Derivative Liability	0		0
Accounts Payable and Accrued Liabilities [Member]
Derivatives, Fair Value [Line Items]
Derivative Asset	5		9
Derivative Liability	29		43
Commodity Contract [Member] | Derivatives not designated as hedging instruments
Derivatives, Fair Value [Line Items]
Asset position	321		331
Liability position	65		100
Derivative Asset, Fair Value, Gross Liability	14		1
Derivative Liability, Fair Value, Gross Asset	14		1
Derivative Asset	307		330
Derivative Liability	51		99
Commodity Contract [Member] | Copper Derivatives [Member] | Derivatives not designated as hedging instruments
Derivatives, Fair Value [Line Items]
Asset position	7		0
Liability position	5		7
Derivative Asset, Fair Value, Gross Liability	5		0
Derivative Liability, Fair Value, Gross Asset	5		0
Derivative Asset	2		0
Derivative Liability	0		7
Commodity Contract [Member] | Copper futures and swap contracts [Member] | Derivatives not designated as hedging instruments
Derivatives, Fair Value [Line Items]
Asset position	4	[1]	0	[1]
Liability position	5	[1]	7	[1]
Commodity Contract [Member] | Copper forward contracts [Member] | Derivatives not designated as hedging instruments
Derivatives, Fair Value [Line Items]
Asset position	3		0
Commodity Contract [Member] | Embedded derivatives in provisional sales/purchases contracts [Member] | Derivatives not designated as hedging instruments
Derivatives, Fair Value [Line Items]
Asset position	46		15
Liability position	60		93
Derivative Asset, Fair Value, Gross Liability	9		1
Derivative Liability, Fair Value, Gross Asset	9		1
Derivative Asset	37		14
Derivative Liability	51		92
Commodity Contract [Member] | Crude Oil and Natural Gas Derivatives [Member] | Derivatives not designated as hedging instruments
Derivatives, Fair Value [Line Items]
Asset position	268		316
Liability position	0		0
Derivative Asset	268		316
Derivative Liability	0		0
Commodity Contract [Member] | Crude Oil Options [Member] | Derivatives not designated as hedging instruments
Derivatives, Fair Value [Line Items]
Asset position	268	[2]	316	[2]
Deferred Option Premiums and Accrued Interest [Member]
Derivatives, Fair Value [Line Items]
Derivative Asset	$ 159		$ 210

[1] FCX paid $5 million to brokers at March 31, 2015, and $10 million at December 31, 2014, for margin requirements (recorded in other current assets).

[2] $159 million at March 31, 2015, and $210 million at December 31, 2014, for deferred premiums and accrued interest.