Financial Instruments (Unaudited) Unsettled Derivatives (Details) - USD ($) $ in Millions		Mar. 31, 2016	Dec. 31, 2015
Derivatives, Fair Value [Line Items]
Derivative Asset		$ 64	$ 15
Derivative Liability		25	86
Paid to brokers associated with margin requirements		5	10
Trade Accounts Receivable [Member]
Derivatives, Fair Value [Line Items]
Derivative Asset		61	10
Derivative Liability		9	52
Accounts Payable and Accrued Liabilities [Member]
Derivatives, Fair Value [Line Items]
Derivative Asset		3	5
Derivative Liability		16	34
Commodity Contract [Member] | Derivatives not designated as hedging instruments
Derivatives, Fair Value [Line Items]
Asset position		72	22
Liability position		33	93
Derivative Asset, Fair Value, Gross Liability		8	7
Derivative Liability, Fair Value, Gross Asset		8	7
Derivative Asset		64	15
Derivative Liability		25	86
Commodity Contract [Member] | Copper Derivatives [Member] | Derivatives not designated as hedging instruments
Derivatives, Fair Value [Line Items]
Asset position		4	1
Liability position		8	11
Derivative Asset, Fair Value, Gross Liability		4	1
Derivative Liability, Fair Value, Gross Asset		4	1
Derivative Asset		0	0
Derivative Liability		4	10
Commodity Contract [Member] | Copper futures and swap contracts [Member] | Derivatives not designated as hedging instruments
Derivatives, Fair Value [Line Items]
Asset position	[1]	4	1
Liability position	[1]	6	11
Commodity Contract [Member] | Copper forward contracts [Member] | Derivatives not designated as hedging instruments
Derivatives, Fair Value [Line Items]
Liability position		2	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		68	21
Liability position		25	82
Derivative Asset, Fair Value, Gross Liability		4	6
Derivative Liability, Fair Value, Gross Asset		4	6
Derivative Asset		64	15
Derivative Liability		$ 21	$ 76

[1] FCX paid $5 million to brokers at March 31, 2016, and $10 million at December 31, 2015, for margin requirements (recorded in other current assets).