Guarantor Financial Statements (Unaudited) Condensed Consolidating Balance Sheets (Details) (USD $) In Millions, unless otherwise specified	Mar. 31, 2015		Dec. 31, 2014		Mar. 31, 2014
ASSETS
Current assets	$ 8,854		$ 9,045
Property, plant, equipment and mining development costs, net	26,595		26,220
Oil and gas properties, net - full cost method
Subject to amortization, less accumulated amortization	6,713		9,187
Not subject to amortization	9,665		10,087
Investments in consolidated subsidiaries	0		0
Other assets	4,238		4,135
Total assets	56,065		58,674		63,732
LIABILITIES AND EQUITY
Current liabilities	4,410		5,172
Long-term debt, less current portion	19,754		18,371
Deferred income taxes	5,625		6,398
Environmental and asset retirement obligations, less current portion	3,678		3,647
Other liabilities	1,812		1,861
Total liabilities	35,279		35,449
Redeemable noncontrolling interest	755		751
Equity:
Stockholders' equity	15,793		18,287
Noncontrolling interests	4,238		4,187
Total equity	20,031		22,474
Total liabilities and equity	56,065		58,674
FCX Issuer [Member]
ASSETS
Current assets	288		323
Property, plant, equipment and mining development costs, net	21		22
Oil and gas properties, net - full cost method
Subject to amortization, less accumulated amortization	0		0
Not subject to amortization	0		0
Investments in consolidated subsidiaries	25,828		28,765
Other assets	9,814		8,914
Total assets	35,951		38,024
LIABILITIES AND EQUITY
Current liabilities	1,819		1,592
Long-term debt, less current portion	15,900		14,930
Deferred income taxes	2,390	[1]	3,161	[1]
Environmental and asset retirement obligations, less current portion	0		0
Other liabilities	49		54
Total liabilities	20,158		19,737
Redeemable noncontrolling interest	0		0
Equity:
Stockholders' equity	15,793		18,287
Noncontrolling interests	0		0
Total equity	15,793		18,287
Total liabilities and equity	35,951		38,024
FM O&G LLC Guarantor [Member]
ASSETS
Current assets	3,623		2,635
Property, plant, equipment and mining development costs, net	48		46
Oil and gas properties, net - full cost method
Subject to amortization, less accumulated amortization	2,309		3,296
Not subject to amortization	2,553		2,447
Investments in consolidated subsidiaries	4,117		6,460
Other assets	4,276		3,947
Total assets	16,926		18,831
LIABILITIES AND EQUITY
Current liabilities	400		560
Long-term debt, less current portion	4,771		3,874
Deferred income taxes	0		0
Environmental and asset retirement obligations, less current portion	303		302
Other liabilities	3,359		3,372
Total liabilities	8,833		8,108
Redeemable noncontrolling interest	0		0
Equity:
Stockholders' equity	8,093		10,723
Noncontrolling interests	0		0
Total equity	8,093		10,723
Total liabilities and equity	16,926		18,831
Non-Guarantor Subsidiaries [Member]
ASSETS
Current assets	8,257		8,659
Property, plant, equipment and mining development costs, net	26,526		26,152
Oil and gas properties, net - full cost method
Subject to amortization, less accumulated amortization	4,404		5,907
Not subject to amortization	7,112		7,640
Investments in consolidated subsidiaries	7,005		10,246
Other assets	4,160		4,061
Total assets	57,464		62,665
LIABILITIES AND EQUITY
Current liabilities	5,505		5,592
Long-term debt, less current portion	9,625		8,879
Deferred income taxes	3,235		3,237
Environmental and asset retirement obligations, less current portion	3,375		3,345
Other liabilities	1,874		1,910
Total liabilities	23,614		22,963
Redeemable noncontrolling interest	755		751
Equity:
Stockholders' equity	29,376		35,268
Noncontrolling interests	3,719		3,683
Total equity	33,095		38,951
Total liabilities and equity	57,464		62,665
Eliminations [Member]
ASSETS
Current assets	(3,314)		(2,572)
Property, plant, equipment and mining development costs, net	0		0
Oil and gas properties, net - full cost method
Subject to amortization, less accumulated amortization	0		(16)
Not subject to amortization	0		0
Investments in consolidated subsidiaries	(36,950)		(45,471)
Other assets	(14,012)		(12,787)
Total assets	(54,276)		(60,846)
LIABILITIES AND EQUITY
Current liabilities	(3,314)		(2,572)
Long-term debt, less current portion	(10,542)		(9,312)
Deferred income taxes	0		0
Environmental and asset retirement obligations, less current portion	0		0
Other liabilities	(3,470)		(3,475)
Total liabilities	(17,326)		(15,359)
Redeemable noncontrolling interest	0		0
Equity:
Stockholders' equity	(37,469)		(45,991)
Noncontrolling interests	519		504
Total equity	(36,950)		(45,487)
Total liabilities and equity	$ (54,276)		$ (60,846)

[1] All U.S. related deferred income taxes are recorded at the parent company.