DISPOSITIONS AND ACQUISITIONS (Purchase Price Allocation) (Details) (USD $) Share data in Millions, unless otherwise specified	3 Months Ended	7 Months Ended	12 Months Ended			3 Months Ended		6 Months Ended
	Dec. 31, 2014	Dec. 31, 2013	Dec. 31, 2014	Dec. 31, 2013	Dec. 31, 2012	Jun. 30, 2014		Jun. 30, 2014		May 31, 2013	Jun. 03, 2013
Business Acquisition [Line Items]
Current assets						$ 1,291,000,000		$ 1,291,000,000
Subject to amortization		12,200,000,000		12,200,000,000		12,198,000,000		12,198,000,000
Not subject to amortization		11,100,000,000		11,100,000,000		11,112,000,000		11,112,000,000
Property, plant, and equipment						262,000,000		262,000,000
Investment in MMR						0	[1]	0	[1]
Other assets						394,000,000		394,000,000
Current liabilities						(1,080,000,000)		(1,080,000,000)
Debt (current and long-term)						(11,251,000,000)		(11,251,000,000)
Deferred income taxes						(3,917,000,000)	[2]	(3,917,000,000)	[2]
Other long-term liabilities						(1,061,000,000)		(1,061,000,000)
Redeemable noncontrolling interest						(967,000,000)		(967,000,000)
Total fair value, excluding goodwill						6,981,000,000		6,981,000,000
Goodwill	0	1,916,000,000	0	1,916,000,000		1,938,000,000		1,938,000,000
Total purchase price						8,919,000,000		8,919,000,000
Business Combinations, Tax Rate, Fair Value Adjustments, Percent		38.00%
Federal Statutory Income Tax Rate, Percent		35.00%	35.00%	35.00%	35.00%
State and Local Income Taxes, Percent		3.00%	27.00%	0.00%	0.00%
Goodwill impairment	(1,700,000,000)		(1,717,000,000)	0	0
Plains Exploration & Production Company [Member]
Business Acquisition [Line Items]
Current assets						1,193,000,000		1,193,000,000
Subject to amortization						11,447,000,000		11,447,000,000
Not subject to amortization						9,401,000,000		9,401,000,000
Property, plant, and equipment						261,000,000		261,000,000
Investment in MMR						848,000,000	[1]	848,000,000	[1]
Other assets						12,000,000		12,000,000
Current liabilities						(906,000,000)		(906,000,000)
Debt (current and long-term)						(10,631,000,000)		(10,631,000,000)
Deferred income taxes						(3,917,000,000)	[2]	(3,917,000,000)	[2]
Other long-term liabilities						(799,000,000)		(799,000,000)
Redeemable noncontrolling interest						(708,000,000)		(708,000,000)
Total fair value, excluding goodwill						6,201,000,000		6,201,000,000
Goodwill						438,000,000		438,000,000
Total purchase price						6,639,000,000		6,639,000,000		6,639,000,000
McMoRan Exploration Co [Member]
Business Acquisition [Line Items]
Investment Owned, Balance, Shares										51
Current assets						98,000,000		98,000,000
Subject to amortization						751,000,000		751,000,000
Not subject to amortization						1,711,000,000		1,711,000,000
Property, plant, and equipment						1,000,000		1,000,000
Investment in MMR						0	[1]	0	[1]	848,000,000
Other assets						382,000,000		382,000,000
Current liabilities						(174,000,000)		(174,000,000)
Debt (current and long-term)						(620,000,000)		(620,000,000)
Deferred income taxes						0	[2]	0	[2]
Other long-term liabilities						(262,000,000)		(262,000,000)
Redeemable noncontrolling interest						(259,000,000)		(259,000,000)
Total fair value, excluding goodwill						1,628,000,000		1,628,000,000
Goodwill						1,500,000,000		1,500,000,000
Total purchase price						3,128,000,000		3,128,000,000			3,128,000,000
Plains Exploration & Production Company and McMoRan Exploration Co [Member]
Business Acquisition [Line Items]
Goodwill	0	1,916,000,000	0	1,916,000,000	0
Business Combination, Adjustment to Recognized Identifiable Assets Acquired and Liabilities Assumed Oil and Gas Properties Subject to Depletion						5,000,000
Business Combination, Adjustment to Recognized Identifiable Assets Acquired and Liabilities Assumed Oil and Gas Properties Not Subject to Depletion						25,000,000
Increase in other assets (deferred income tax asset)						42,000,000
(Decrease) increase in goodwill			22,000,000	1,916,000,000		22,000,000
Goodwill impairment			(1,717,000,000)
Eagle Ford [Member]
Business Acquisition [Line Items]
(Decrease) increase in goodwill			(221,000,000)					221,000,000
Intersubsegment Eliminations [Member]
Business Acquisition [Line Items]
Current assets						0		0
Subject to amortization						0		0
Not subject to amortization						0		0
Property, plant, and equipment						0		0
Investment in MMR						(848,000,000)	[1]	(848,000,000)	[1]
Other assets						0		0
Current liabilities						0		0
Debt (current and long-term)						0		0
Deferred income taxes						0	[2]	0	[2]
Other long-term liabilities						0		0
Redeemable noncontrolling interest						0		0
Total fair value, excluding goodwill						(848,000,000)		(848,000,000)
Goodwill						0		0
Total purchase price						$ (848,000,000)		$ (848,000,000)
Minimum [Member]
Business Acquisition [Line Items]
Fair Value Inputs, Energy Measure	62		62							90
Maximum [Member]
Business Acquisition [Line Items]
Fair Value Inputs, Energy Measure	80		80							98

[1] PXP owned 51 million shares of MMR common stock, which were eliminated in FCX's consolidated balance sheet at the acquisition date of MMR.

[2] Deferred income taxes have been recognized based on the estimated fair value adjustments to net assets using a 38 percent tax rate, which reflected a 35 percent federal statutory rate and a 3 percent weighted-average of the applicable statutory state tax rates (net of federal benefit).