Acquisitions (Unaudited) (Details) (USD $)	3 Months Ended		6 Months Ended				1 Months Ended		6 Months Ended	1 Months Ended		3 Months Ended	6 Months Ended	12 Months Ended			3 Months Ended			1 Months Ended	3 Months Ended		3 Months Ended	6 Months Ended				3 Months Ended	6 Months Ended		3 Months Ended	6 Months Ended		3 Months Ended	6 Months Ended		3 Months Ended	6 Months Ended		3 Months Ended			6 Months Ended
	Jun. 30, 2013	Jun. 30, 2012	Jun. 30, 2013	Jun. 30, 2012	Jun. 03, 2013		May 31, 2013 Plains Exploration & Production Company [Member]		Jun. 30, 2013 Plains Exploration & Production Company [Member]	Jun. 30, 2013 McMoRan Exploration Co [Member]	May 31, 2013 McMoRan Exploration Co [Member]	Jun. 30, 2013 McMoRan Exploration Co [Member]	Jun. 30, 2013 McMoRan Exploration Co [Member]	Dec. 31, 2012 McMoRan Exploration Co [Member]	Jun. 03, 2013 McMoRan Exploration Co [Member]		Jun. 30, 2013 Kokkola Cobalt Chemicals Refinery [Member]	Mar. 31, 2013 Kokkola Cobalt Chemicals Refinery [Member]	Mar. 29, 2013 Kokkola Cobalt Chemicals Refinery [Member]	Feb. 28, 2012 Senior Notes [Member]	Mar. 31, 2013 Senior Notes [Member]	Mar. 07, 2013 Senior Notes [Member]	Jun. 30, 2013 Bank Term Loan [Member]	Jun. 30, 2013 Bank Term Loan [Member]	Feb. 14, 2013 Bank Term Loan [Member]	Mar. 29, 2013 Lundin Mining Corporation [Member] Kokkola Cobalt Chemicals Refinery [Member]	Mar. 29, 2013 La Generale des Carrieres et des Mines [Member] Kokkola Cobalt Chemicals Refinery [Member]	Mar. 31, 2013 2.375% Senior Notes due March 2018 [Member] Senior Notes [Member]	Jun. 30, 2013 2.375% Senior Notes due March 2018 [Member] Senior Notes [Member]	Mar. 07, 2013 2.375% Senior Notes due March 2018 [Member] Senior Notes [Member]	Mar. 31, 2013 3.100% Senior Notes due March 2020 [Member] Senior Notes [Member]	Jun. 30, 2013 3.100% Senior Notes due March 2020 [Member] Senior Notes [Member]	Mar. 07, 2013 3.100% Senior Notes due March 2020 [Member] Senior Notes [Member]	Mar. 31, 2013 3.875% Senior Notes due March 2023 [Member] Senior Notes [Member]	Jun. 30, 2013 3.875% Senior Notes due March 2023 [Member] Senior Notes [Member]	Mar. 07, 2013 3.875% Senior Notes due March 2023 [Member] Senior Notes [Member]	Mar. 31, 2013 5.450% Senior Notes due March 2043 [Member] Senior Notes [Member]	Jun. 30, 2013 5.450% Senior Notes due March 2043 [Member] Senior Notes [Member]	Mar. 07, 2013 5.450% Senior Notes due March 2043 [Member] Senior Notes [Member]	Jun. 30, 2013 Oil & Gas Operations [Member]		Jun. 30, 2012 Oil & Gas Operations [Member]	Jun. 30, 2013 Oil & Gas Operations [Member]		Jun. 30, 2012 Oil & Gas Operations [Member]	Jun. 03, 2013 Common Stock [Member] McMoRan Exploration Co [Member]		Jun. 03, 2013 5.75% Convertible Perpetual Preferred Stock, Series 2 [Member] McMoRan Exploration Co [Member]
Business Acquisition [Line Items]
Business Acquisition, Effective Date of Acquisition									May 31, 2013				Jun. 03, 2013				Mar. 29, 2013
Debt Instrument, Face Amount																						$ 6,500,000,000			$ 4,000,000,000					$ 1,500,000,000			$ 1,000,000,000			$ 2,000,000,000			$ 2,000,000,000
Proceeds from Issuance of Long-term Debt																				2,970,000,000	6,489,000,000			4,000,000,000					1,500,000,000			1,000,000,000			1,999,000,000			1,991,000,000
Term of Debt Agreement																							5 years					5 years			7 years			10 years			30 years
Business Acquisition, Agreed-Upon Cost of Entity Acquired, Cash Paid Per Share							$ 25.00								$ 14.75
Payment to Acquire Businesses, Per Share Consideration, Total							3,300,000,000
Payment to Acquire Businesses, Consideration for Equity Awards							7,000,000
Payments of Dividends							411,000,000
Common Stock, Dividends, Per Share, Declared	$ 1.3125	$ 0.3125	$ 1.625	$ 0.625			$ 3
Dividends Payable, Date to be Paid							May 31, 2013
Number of shares of common stock acquired							132,280,000	[1]																																						112,362,000.000	[2]
Exchange ratio of FCX common stock for each acquiree share							0.6531
Business Acquisition, Equity Interest Issued or Issuable, Number of Shares Excluding Shares Related to Stock-based Awards							86,392,000
Shares of FCX common stock issued for equity awards							4,769,000
Total shares of FCX common stock issued							91,000,000
Closing share price of common stock							$ 31.05				$ 16.63				$ 16.75
FCX stock consideration							2,831,000,000
Cash consideration							3,725,000,000	[3]		1,657,000,000
Employee stock-based awards							78,000,000			63,000,000
Total purchase price					8,914,000,000		6,634,000,000			3,128,000,000		3,128,000,000	3,128,000,000		3,128,000,000
Buinsess Acquisition, Agreed-Upon Royalty Trust Units Issued or Issuable, Per Share of Target Company										1.15
Royalty Interest in Future Production															5.00%
Business Acquisition, Date of Acquisition Agreement														Dec. 05, 2012
Number Of Shares Of Investee Preferred Stock Purchased											500,000
Preferred Stock, Dividend Rate, Percentage											5.75%
Cost Method Investments											432,000,000
Investment Owned, Balance, Shares											51,000,000
Business Combination, Recognized Identifiable Assets Acquired and Liabilities Assumed, Current Assets, Marketable Securities					0	[4]	848,000,000	[4]			848,000,000				0	[4]																														854,000,000		554,000,000
Business Combination, Step Acquisition, Equity Interest in Acquiree, Fair Value										1,400,000,000
Business Combination, Step Acquisition, Equity Interest in Acquiree, Remeasurement Gain	128,000,000	0	128,000,000	0								128,000,000
Revenues	4,288,000,000	4,475,000,000	8,871,000,000	9,080,000,000																																				336,000,000	[5]	0	336,000,000	[5]	0
Operating income (loss)	639,000,000	1,311,000,000	1,994,000,000	3,045,000,000																																				64,000,000		0	64,000,000		0
Business Combination, Acquisition Related Costs	506,000,000																																							61,000,000			75,000,000
Deferred Finance Costs, Noncurrent, Net	95,000,000		95,000,000
Investment Owned, Percent of Net Assets																			56.00%
Noncontrolling Interest, Ownership Percentage by Noncontrolling Owners																										24.00%	20.00%
Business Combination, Consideration Transferred																		382,000,000
Business Acquisition, Cost of Acquired Entity, Cash Paid							3,800,000,000			1,720,000,000								34,000,000
Business Combination, Purchase Price, Working Capital Adjustment																		27,000,000
Business Acquisition, Cash Consideration Funding Percentage																			70.00%							30.00%
Business Acquisition, Contingent Consideration, Potential Cash Payment																			$ 110,000,000
Buisness Acquisition, Term of Contingent Consideration																	3 years

[1] Adjusted for cash paid in lieu of fractional shares.

[2] Excluded 51 million shares of MMR common stock owned by FCX through its acquisition of PXP on May 31, 2013.

[3] Cash consideration includes the payment of $25.00 in cash for each PXP share ($3.3 billion), cash paid in lieu of any fractional shares of FCX common stock, cash paid for certain equity awards ($7 million), and the value of the $3 per share PXP special cash dividend ($411 million) paid on May 31, 2013.

[4] PXP owned 51 million shares of MMR common stock, which was eliminated in FCX's condensed consolidated balance sheet at June 30, 2013.

[5] Included unfavorable adjustments of $35 million related to oil and gas derivative instruments. For further discussion, refer to Note 9.