Guarantor Financial Statements (Unaudited) Condensed Consolidating Balance Sheets (Details) - USD ($) $ in Millions		Mar. 31, 2016	Dec. 31, 2015	Mar. 31, 2015
ASSETS
Current assets		$ 7,233	$ 7,462
Property, plant, equipment and mining development costs, net		27,376	27,509
Oil and gas properties, net - full cost method
Subject to amortization, less accumulated amortization and impairment		1,700	2,262
Not subject to amortization		1,743	4,831
Investments in consolidated subsidiaries		0	0
Other assets		4,612	4,513
Total assets		42,664	46,577	$ 56,065
LIABILITIES AND EQUITY
Current liabilities		4,426	4,307
Long-term debt, less current portion		19,638	19,779
Deferred income taxes		4,442	4,288
Environmental and asset retirement obligations, less current portion		3,762	3,739
Investments in consolidated subsidiaries		0	0
Other liabilities		1,659	1,656
Total liabilities		33,927	33,769
Redeemable noncontrolling interest		767	764
Equity:
Stockholders' equity		3,692	7,828
Noncontrolling interests		4,278	4,216
Total equity		7,970	12,044
Total liabilities and equity		42,664	46,577
FCX Issuer [Member]
ASSETS
Current assets		272	181
Property, plant, equipment and mining development costs, net		25	26
Oil and gas properties, net - full cost method
Subject to amortization, less accumulated amortization and impairment		0	0
Not subject to amortization		0	0
Investments in consolidated subsidiaries		20,674	24,311
Other assets		1,135	5,038
Total assets		22,106	29,556
LIABILITIES AND EQUITY
Current liabilities		2,714	6,012
Long-term debt, less current portion		14,599	14,735
Deferred income taxes	[1]	1,060	941
Environmental and asset retirement obligations, less current portion		0	0
Investments in consolidated subsidiaries		0	0
Other liabilities		41	40
Total liabilities		18,414	21,728
Redeemable noncontrolling interest		0	0
Equity:
Stockholders' equity		3,692	7,828
Noncontrolling interests		0	0
Total equity		3,692	7,828
Total liabilities and equity		22,106	29,556
FM O&G LLC Guarantor [Member]
ASSETS
Current assets		2,600	3,831
Property, plant, equipment and mining development costs, net		59	57
Oil and gas properties, net - full cost method
Subject to amortization, less accumulated amortization and impairment		517	710
Not subject to amortization		415	1,393
Investments in consolidated subsidiaries		0	0
Other assets		34	1,826
Total assets		3,625	7,817
LIABILITIES AND EQUITY
Current liabilities		660	666
Long-term debt, less current portion		6,592	5,883
Deferred income taxes		0	0
Environmental and asset retirement obligations, less current portion		310	305
Investments in consolidated subsidiaries		483	0
Other liabilities		3,355	3,360
Total liabilities		11,400	10,214
Redeemable noncontrolling interest		0	0
Equity:
Stockholders' equity		(7,775)	(2,397)
Noncontrolling interests		0	0
Total equity		(7,775)	(2,397)
Total liabilities and equity		3,625	7,817
Non-Guarantor Subsidiaries [Member]
ASSETS
Current assets		8,092	10,982
Property, plant, equipment and mining development costs, net		27,292	27,426
Oil and gas properties, net - full cost method
Subject to amortization, less accumulated amortization and impairment		1,183	1,552
Not subject to amortization		1,326	3,432
Investments in consolidated subsidiaries		0	0
Other assets		4,533	4,447
Total assets		42,426	47,839
LIABILITIES AND EQUITY
Current liabilities		4,782	5,155
Long-term debt, less current portion		11,818	11,594
Deferred income taxes		3,382	3,347
Environmental and asset retirement obligations, less current portion		3,452	3,434
Investments in consolidated subsidiaries		7,775	2,397
Other liabilities		1,751	1,747
Total liabilities		32,960	27,674
Redeemable noncontrolling interest		767	764
Equity:
Stockholders' equity		4,966	15,725
Noncontrolling interests		3,733	3,676
Total equity		8,699	19,401
Total liabilities and equity		42,426	47,839
Eliminations [Member]
ASSETS
Current assets		(3,731)	(7,532)
Property, plant, equipment and mining development costs, net		0	0
Oil and gas properties, net - full cost method
Subject to amortization, less accumulated amortization and impairment		0	0
Not subject to amortization		2	6
Investments in consolidated subsidiaries		(20,674)	(24,311)
Other assets		(1,090)	(6,798)
Total assets		(25,493)	(38,635)
LIABILITIES AND EQUITY
Current liabilities		(3,730)	(7,526)
Long-term debt, less current portion		(13,371)	(12,433)
Deferred income taxes		0	0
Environmental and asset retirement obligations, less current portion		0	0
Investments in consolidated subsidiaries		(8,258)	(2,397)
Other liabilities		(3,488)	(3,491)
Total liabilities		(28,847)	(25,847)
Redeemable noncontrolling interest		0	0
Equity:
Stockholders' equity		2,809	(13,328)
Noncontrolling interests		545	540
Total equity		3,354	(12,788)
Total liabilities and equity		$ (25,493)	$ (38,635)

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