Financial Instruments (Unaudited) Unsettled Derivatives (Details) (USD $) In Millions, unless otherwise specified	Jun. 30, 2013		Dec. 31, 2012
Derivatives, Fair Value [Line Items]
Paid to brokers associated with margin requirements	$ 20		$ 7
Derivative Asset	61		33
Derivative Liability	223		20
Trade Accounts Receivable [Member]
Derivatives, Fair Value [Line Items]
Derivative Asset	7		24
Derivative Liability	95		9
Other Current Assets [Member]
Derivatives, Fair Value [Line Items]
Derivative Asset	49		5
Derivative Liability	0		0
Other Assets [Member]
Derivatives, Fair Value [Line Items]
Derivative Asset	1		0
Derivative Liability	0		0
Accounts Payable and Accrued Liabilities [Member]
Derivatives, Fair Value [Line Items]
Derivative Asset	4		4
Derivative Liability	71		11
Other Liabilities [Member]
Derivatives, Fair Value [Line Items]
Derivative Asset	0		0
Derivative Liability	57		0
Commodity Contract [Member] | Derivatives not designated as hedging instruments
Derivatives, Fair Value [Line Items]
Asset position	92		41
Liability position	254		28
Derivative Asset, Fair Value, Gross Liability	31		8
Derivative Liability, Fair Value, Gross Asset	31		8
Derivative Asset	61		33
Derivative Liability	223		20
Commodity Contract [Member] | Copper Derivatives [Member] | Derivatives not designated as hedging instruments
Derivatives, Fair Value [Line Items]
Asset position	0		5
Liability position	17		1
Derivative Asset, Fair Value, Gross Liability	0		0
Derivative Liability, Fair Value, Gross Asset	0		0
Derivative Asset	0		5
Derivative Liability	17		1
Commodity Contract [Member] | Copper futures and swap contracts [Member] | Derivatives not designated as hedging instruments
Derivatives, Fair Value [Line Items]
Asset position	0	[1]	5	[1]
Liability position	14	[1]	1	[1]
Commodity Contract [Member] | Copper forward contracts [Member] | Derivatives not designated as hedging instruments
Derivatives, Fair Value [Line Items]
Liability 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	11		36
Liability position	121		27
Derivative Asset, Fair Value, Gross Liability	0		8
Derivative Liability, Fair Value, Gross Asset	0		8
Derivative Asset	11		28
Derivative Liability	121		19
Commodity Contract [Member] | Crude Oil and Natural Gas Derivatives [Member] | Derivatives not designated as hedging instruments
Derivatives, Fair Value [Line Items]
Asset position	81		0
Liability position	116		0
Derivative Asset, Fair Value, Gross Liability	31		0
Derivative Liability, Fair Value, Gross Asset	31		0
Derivative Asset	50		0
Derivative Liability	85		0
Commodity Contract [Member] | Crude Oil and Natural Gas Swaps [Member] | Derivatives not designated as hedging instruments
Derivatives, Fair Value [Line Items]
Asset position	81		0
Crude Oil Options [Member] | Embedded derivatives in provisional sales/purchases contracts [Member] | Derivatives not designated as hedging instruments
Derivatives, Fair Value [Line Items]
Liability position	116		0
Deferred Option Premiums and Accrued Interest [Member]
Derivatives, Fair Value [Line Items]
Derivative Liability	$ 478

[1] FCX paid $20 million to brokers at June 30, 2013, and $7 million at December 31, 2012, for margin requirements (recorded in other current assets).