Business Segments (Unaudited) (Details) - USD ($) $ in Millions		3 Months Ended				6 Months Ended
		Jun. 30, 2015		Jun. 30, 2014		Jun. 30, 2015		Jun. 30, 2014		Dec. 31, 2014
Revenues:
Unaffiliated customers		$ 4,248		$ 5,522		$ 8,401		$ 10,507
Intersegment		0		0		0		0
Production and delivery		2,848		3,082		5,760		5,819
Depreciation, depletion and amortization		890		1,013		1,829		1,979
Impairment of oil and gas properties		2,686		0		5,790		0
Selling, general and administrative expenses		151		164		305		299
Mining exploration and research expenses		36		34		69		64
Environmental obligations and shutdown costs		11		76		24		82
Net gain on sale of assets		0		0		(39)		0
Operating income (loss)		(2,374)		1,153		(5,337)		2,264
Interest expense, net		149		164		295		325
Provision for (benefit from) income taxes		(687)		328		(1,382)		685
Total Assets		54,008		63,903		54,008		63,903		$ 58,674
Capital expenditures		1,661		1,950		3,528		3,562
Lower of cost or market inventory adjustments		(59)				(63)		0
Mining Operations [Member]
Revenues:
Unaffiliated customers		3,679		4,286		7,332		8,010
Intersegment		0		0		0		0
Production and delivery		2,565		2,754		5,191		5,180
Depreciation, depletion and amortization		402		394		807		740
Impairment of oil and gas properties		0				0
Selling, general and administrative expenses		40		42		81		80
Mining exploration and research expenses		36		34		69		64
Environmental obligations and shutdown costs		11		76		24		82
Net gain on sale of assets						(39)
Operating income (loss)		625		986		1,199		1,864
Interest expense, net		42		22		87		45
Provision for (benefit from) income taxes		128		140		207		309
Total Assets		38,434		37,491		38,434		37,491
Capital expenditures		854		1,049		1,694		2,073
North America Copper Mines [Member]
Revenues:
Unaffiliated customers		272		107		493		191
Intersegment		1,133		1,362		2,247		2,564
Production and delivery		962		870		1,905		1,656
Depreciation, depletion and amortization		139		128		272		235
Impairment of oil and gas properties		0				0
Selling, general and administrative expenses		2		1		3		2
Mining exploration and research expenses		2		2		5		4
Environmental obligations and shutdown costs		0		0		0		0
Net gain on sale of assets						(39)
Operating income (loss)		300		468		594		858
Interest expense, net		1		1		2		2
Provision for (benefit from) income taxes		0		0		0		0
Total Assets		9,388		9,497		9,388		9,497
Capital expenditures		107		324		214		627
Morenci [Member]
Revenues:
Unaffiliated customers		180		52		286		75
Intersegment		427		474		877		918
Production and delivery		386		312		760		595
Depreciation, depletion and amortization		55		43		106		77
Impairment of oil and gas properties		0				0
Selling, general and administrative expenses		0		1		1		1
Mining exploration and research expenses		0		0		0		0
Environmental obligations and shutdown costs		0		0		0		0
Net gain on sale of assets						0
Operating income (loss)		166		170		296		320
Interest expense, net		0		0		1		1
Provision for (benefit from) income taxes		0		0		0		0
Total Assets		3,806		3,675		3,806		3,675
Capital expenditures		79		289		163		533
Other North America Copper Mines [Member]
Revenues:
Unaffiliated customers		92		55		207		116
Intersegment		706		888		1,370		1,646
Production and delivery		576	[1]	558		1,145	[2]	1,061
Depreciation, depletion and amortization		84		85		166		158
Impairment of oil and gas properties		0				0
Selling, general and administrative expenses		2		0		2		1
Mining exploration and research expenses		2		2		5		4
Environmental obligations and shutdown costs		0		0		0		0
Net gain on sale of assets						(39)
Operating income (loss)		134		298		298		538
Interest expense, net		1		1		1		1
Provision for (benefit from) income taxes		0		0		0		0
Total Assets		5,582		5,822		5,582		5,822
Capital expenditures		28		35		51		94
Lower of cost or market inventory adjustments		(11)				(11)
South America Mines [Member]
Revenues:
Unaffiliated customers		416		945		895		1,647
Intersegment		37		86		44		282
Production and delivery		315		530		660		1,006
Depreciation, depletion and amortization		72		95		147		182
Impairment of oil and gas properties		0				0
Selling, general and administrative expenses		1		2		2		4
Mining exploration and research expenses		0		0		0		0
Environmental obligations and shutdown costs		0		0		0		0
Net gain on sale of assets						0
Operating income (loss)		65		404		130		737
Interest expense, net		0		0		1		0
Provision for (benefit from) income taxes		6		140		30		267
Total Assets		10,502		10,667		10,502		10,667
Capital expenditures		457		416		902		839
Cerro Verde [Member]
Revenues:
Unaffiliated customers		195		421		443		701
Intersegment		37		23		51		87
Production and delivery		165		195		363		360
Depreciation, depletion and amortization		40		43		77		79
Impairment of oil and gas properties		0				0
Selling, general and administrative expenses		0		1		1		2
Mining exploration and research expenses		0		0		0		0
Environmental obligations and shutdown costs		0		0		0		0
Net gain on sale of assets						0
Operating income (loss)		27		205		53		347
Interest expense, net		0		0		1		0
Provision for (benefit from) income taxes		(5)		73		0		130
Total Assets		8,567		6,876		8,567		6,876
Capital expenditures		444		391		875		791
Other South America Mines [Member]
Revenues:
Unaffiliated customers		221	[3]	524	[3]	452	[4]	946	[4]
Intersegment		0	[3]	63	[3]	(7)	[4],[5]	195	[4]
Production and delivery		150	[3]	335	[3]	297	[4]	646	[4]
Depreciation, depletion and amortization		32	[3]	52	[3]	70	[4]	103	[4]
Impairment of oil and gas properties		0	[3]			0	[4]
Selling, general and administrative expenses		1	[3]	1	[3]	1	[4]	2	[4]
Mining exploration and research expenses		0	[3]	0	[3]	0	[4]	0	[4]
Environmental obligations and shutdown costs		0	[3]	0	[3]	0	[4]	0	[4]
Net gain on sale of assets	[4]					0
Operating income (loss)		38	[3]	199	[3]	77	[4]	390	[4]
Interest expense, net		0	[3]	0	[3]	0	[4]	0	[4]
Provision for (benefit from) income taxes		11	[3]	67	[3]	30	[4]	137	[4]
Total Assets	[3]	1,935		3,791		1,935		3,791
Capital expenditures		13	[3]	25	[3]	27	[4]	48	[4]
Indonesia - Grasberg [Member]
Revenues:
Unaffiliated customers		792	[6]	523	[6]	1,413	[7]	985	[7]
Intersegment		(2)	[8]	0		(16)	[5]	8
Production and delivery		455		511		894		894
Depreciation, depletion and amortization		78		54		148		102
Impairment of oil and gas properties		0				0
Selling, general and administrative expenses		25		25		50		46
Mining exploration and research expenses		0		0		0		0
Environmental obligations and shutdown costs		0		0		0		0
Net gain on sale of assets						0
Operating income (loss)		232		(67)		305		(49)
Interest expense, net		0		0		0		0
Provision for (benefit from) income taxes		95		(33)		124		(15)
Total Assets		8,959		7,972		8,959		7,972
Capital expenditures		213		243		438		479
Africa - Tenke [Member]
Revenues:
Unaffiliated customers		310		386		692		692
Intersegment		41		32		69		53
Production and delivery		190		198		425		350
Depreciation, depletion and amortization		57		63		130		114
Impairment of oil and gas properties		0				0
Selling, general and administrative expenses		3		3		6		6
Mining exploration and research expenses		0		0		0		0
Environmental obligations and shutdown costs		0		0		0		0
Net gain on sale of assets						0
Operating income (loss)		101		154		200		275
Interest expense, net		0		0		0		0
Provision for (benefit from) income taxes		27		33		53		57
Total Assets		5,125		4,952		5,125		4,952
Capital expenditures		58		29		97		60
Molybdenum mines [Member]
Revenues:
Unaffiliated customers		0		0		0		0
Intersegment		102		170		215		296
Production and delivery		84	[1]	81		167	[2]	157
Depreciation, depletion and amortization		25		24		51		46
Impairment of oil and gas properties		0				0
Selling, general and administrative expenses		0		0		0		0
Mining exploration and research expenses		0		0		0		0
Environmental obligations and shutdown costs		0		0		0		0
Net gain on sale of assets						0
Operating income (loss)		(7)		65		(3)		93
Interest expense, net		0		0		0		0
Provision for (benefit from) income taxes		0		0		0		0
Total Assets		2,052		2,095		2,052		2,095
Capital expenditures		4		14		7		33
Lower of cost or market inventory adjustments		(3)				(3)
Rod & Refining [Member]
Revenues:
Unaffiliated customers		1,089		1,234		2,151		2,380
Intersegment		8		8		15		16
Production and delivery		1,088		1,233		2,151		2,381
Depreciation, depletion and amortization		3		3		5		5
Impairment of oil and gas properties		0				0
Selling, general and administrative expenses		0		0		0		0
Mining exploration and research expenses		0		0		0		0
Environmental obligations and shutdown costs		0		0		0		0
Net gain on sale of assets						0
Operating income (loss)		6		6		10		10
Interest expense, net		0		0		0		0
Provision for (benefit from) income taxes		0		0		0		0
Total Assets		286		299		286		299
Capital expenditures		0		1		1		2
Atlantic Copper Smelting & Refining [Member]
Revenues:
Unaffiliated customers		495		623		1,035		1,211
Intersegment		5		6		11		11
Production and delivery		468		618		987		1,206
Depreciation, depletion and amortization		9		10		19		20
Impairment of oil and gas properties		0				0
Selling, general and administrative expenses		4		5		9		9
Mining exploration and research expenses		0		0		0		0
Environmental obligations and shutdown costs		0		0		0		0
Net gain on sale of assets						0
Operating income (loss)		19		(4)		31		(13)
Interest expense, net		2		3		5		7
Provision for (benefit from) income taxes		0		0		0		0
Total Assets		786		882		786		882
Capital expenditures		4		5		8		6
Other Mining & Eliminations [Member]
Revenues:
Unaffiliated customers	[9]	305		468		653		904
Intersegment		(1,324)		(1,664)		(2,585)		(3,230)
Production and delivery		(997)	[1]	(1,287)		(1,998)	[2]	(2,470)
Depreciation, depletion and amortization		19		17		35		36
Impairment of oil and gas properties		0				0
Selling, general and administrative expenses		5		6		11		13
Mining exploration and research expenses		34		32		64		60
Environmental obligations and shutdown costs		11		76		24		82
Net gain on sale of assets						0
Operating income (loss)		(91)		(40)		(68)		(47)
Interest expense, net		39		18		79		36
Provision for (benefit from) income taxes		0		0		0		0
Total Assets		1,336		1,127		1,336		1,127
Capital expenditures		11		17		27		27
Lower of cost or market inventory adjustments		(45)				(49)
U.S. Oil & Gas Operations [Member]
Revenues:
Unaffiliated customers		569	[10],[11]	1,236	[10],[11]	1,069	[12],[13]	2,497	[12],[13]
Intersegment		0	[11]	0	[11]	0	[13]	0	[13]
Production and delivery		281	[11]	329	[11]	564	[13]	640	[13]
Depreciation, depletion and amortization		485	[11]	616	[11]	1,015	[13]	1,232	[13]
Impairment of oil and gas properties		2,686	[11]			5,790	[13]
Selling, general and administrative expenses		49	[11]	59	[11]	103	[13]	116	[13]
Mining exploration and research expenses		0	[11]	0	[11]	0	[13]	0	[13]
Environmental obligations and shutdown costs		0	[11]	0	[11]	0	[13]	0	[13]
Net gain on sale of assets	[13]					0
Operating income (loss)		(2,932)	[11]	232	[11]	(6,403)	[13]	509	[13]
Interest expense, net		41	[11]	74	[11]	78	[13]	150	[13]
Provision for (benefit from) income taxes		0	[11]	0	[11]	0	[13]	0	[13]
Total Assets	[11]	15,393		25,293		15,393		25,293
Capital expenditures		777	[11]	903	[11]	1,795	[13]	1,484	[13]
Corporate, Other & Eliminations [Member]
Revenues:
Unaffiliated customers		0		0		0		0
Intersegment		0		0		0		0
Production and delivery		2		(1)		5		(1)
Depreciation, depletion and amortization		3		3		7		7
Impairment of oil and gas properties		0				0
Selling, general and administrative expenses		62		63		121		103
Mining exploration and research expenses		0		0		0		0
Environmental obligations and shutdown costs		0		0		0		0
Net gain on sale of assets						0
Operating income (loss)		(67)		(65)		(133)		(109)
Interest expense, net		66		68		130		130
Provision for (benefit from) income taxes		(815)		188		(1,589)		376
Total Assets		181		1,119		181		1,119
Capital expenditures		30		(2)		39		5
Crude oil and natural gas swaps [Member]
Revenues:
Net mark-to-market gains (losses) on derivative contracts		6		(70)		$ 58		(120)
Pt Smelting [Member]
Segment Reporting Information [Line Items]
Deferred Intercompany Profit, Percentage						25.00%
Revenues:
Revenues		$ 293		$ 540		$ 643		$ 913
Equity Method Investment, Ownership Percentage		25.00%				25.00%

[1] Includes LCM inventory adjustments totaling $11 million at other North America copper mines, $3 million at Molybdenum mines and $45 million at other mining & eliminations (see Note 4).

[2] Includes LCM inventory adjustments totaling $11 million at other North America copper mines, $3 million at Molybdenum mines and $49 million at other mining & eliminations (see Note 4).

[3] Second-quarter 2014 includes the results of the Candelaria and Ojos del Salado mining operations, which were sold in November 2014.

[4] The first six months of 2014 include the results of the Candelaria and Ojos del Salado mining operations, which were sold in November 2014.

[5] Amounts include net reductions for provisional pricing adjustments to prior period open sales. There were no intersegment sales from El Abra or Grasberg for the first six months of 2015.

[6] Includes PT-FI’s sales to PT Smelting totaling $293 million in second-quarter 2015 and $540 million in second-quarter 2014.

[7] Includes PT-FI’s sales to PT Smelting totaling $643 million for the first six months of 2015 and $913 million for the first six months of 2014.

[8] Amounts include net reductions for provisional pricing adjustments to prior period open sales. There were no intersegment sales from Grasberg in second-quarter 2015.

[9] Includes revenues from FCX's molybdenum sales company, which includes sales of molybdenum produced by the Molybdenum mines and by certain of the North and South America copper mines.

[10] Includes net mark-to-market gains (losses) associated with crude oil and natural gas derivative contracts totaling $6 million in second-quarter 2015 and $(70) million in second-quarter 2014.

[11] Second-quarter 2014 includes the results from Eagle Ford, which was sold in June 2014.

[12] Includes net mark-to-market gains (losses) associated with crude oil and natural gas derivative contracts totaling $58 million for the first six months 2015 and $(120) million for the first six months of 2014.

[13] The first six months of 2014 include the results from Eagle Ford, which was sold in June 2014.