Business Segments (Unaudited) (Details) - USD ($) $ in Millions			3 Months Ended				6 Months Ended	9 Months Ended
		May 31, 2016	Sep. 30, 2016		Sep. 30, 2015		Jun. 30, 2016	Sep. 30, 2016		Sep. 30, 2015		May 30, 2016	Dec. 31, 2015
Revenues:
Unaffiliated customers			$ 3,877		$ 3,382			$ 10,453		$ 11,091
Intersegment			0		0			0		0
Production and delivery			2,509		2,595			7,957		7,862
Depreciation, depletion and amortization			643		823			1,937		2,522
Impairment of oil and gas properties			239		3,652			4,317		9,442
Metals inventory adjustments			20		91			27		154
Selling, general and administrative expenses			110		122			408		421
Mining exploration and research expenses			13		26			46		83
Environmental obligations and shutdown (credits) costs			(3)		37			18		61
Net gain on sales of assets			(13)		0			(762)		(39)
Operating income (loss)			359		(3,964)			(3,495)		(9,415)
Interest expense, net			187		157			574		438
Provision for (benefit from) income taxes			(114)		(349)			79		(1,762)
Total Assets			41,400	[1]	50,383	[1]		41,400	[1]	50,383	[1]		$ 46,577
Capital expenditures			494		1,527			2,309		5,055
Assets held for sale			4,663		4,868			4,663		4,868			$ 744
Mining Operations [Member]
Revenues:
Unaffiliated customers			3,450		2,856			9,321		9,496
Intersegment			0		0			0		0
Production and delivery			2,256		2,300			6,395		6,998
Depreciation, depletion and amortization			416		369			1,230		1,046
Impairment of oil and gas properties			0		0			0		0
Metals inventory adjustments			20		91			27		154
Selling, general and administrative expenses			35		35			92		110
Mining exploration and research expenses			13		26			46		83
Environmental obligations and shutdown (credits) costs			(3)		36			17		60
Net gain on sales of assets			1					(748)		(39)
Operating income (loss)			712		(1)			2,262		1,084
Interest expense, net			46		23			137		69
Provision for (benefit from) income taxes			190		23			326		177
Total Assets			36,867		38,200			36,867		38,200
Capital expenditures			333		845			1,233		2,534
North America Copper Mines [Member]
Revenues:
Unaffiliated customers			227		223			567		716
Intersegment			857		946			2,713		3,193
Production and delivery			733		973			2,247		2,867
Depreciation, depletion and amortization			129		136			407		408
Impairment of oil and gas properties			0		0			0		0
Metals inventory adjustments			6		55			6		66
Selling, general and administrative expenses			1		1			4		4
Mining exploration and research expenses			1		1			2		6
Environmental obligations and shutdown (credits) costs			0		3			0		3
Net gain on sales of assets			1					(576)		(39)
Operating income (loss)			213		0			1,190		594
Interest expense, net			1		1			3		3
Provision for (benefit from) income taxes			0		0			0		0
Total Assets			7,421		8,879			7,421		8,879
Capital expenditures			11		94			87		308
Morenci [Member]
Revenues:
Unaffiliated customers			115		165			356		451
Intersegment			358		332			1,119		1,209
Production and delivery			275		357			913		1,117
Depreciation, depletion and amortization			51		51			170		157
Impairment of oil and gas properties			0		0			0		0
Metals inventory adjustments			0		0			0		0
Selling, general and administrative expenses			1		1			2		2
Mining exploration and research expenses			0		0			0		0
Environmental obligations and shutdown (credits) costs			0		0			0		0
Net gain on sales of assets			1					(576)		0
Operating income (loss)			145		88			966		384
Interest expense, net			1		1			2		2
Provision for (benefit from) income taxes			0		0			0		0
Total Assets			2,881		3,720			2,881		3,720
Capital expenditures			6		61			71		224
Other North America Copper Mines [Member]
Revenues:
Unaffiliated customers			112		58			211		265
Intersegment			499		614			1,594		1,984
Production and delivery			458		616	[2]		1,334		1,750	[3]
Depreciation, depletion and amortization			78		85			237		251
Impairment of oil and gas properties			0		0			0		0
Metals inventory adjustments			6		55			6		66
Selling, general and administrative expenses			0		0			2		2
Mining exploration and research expenses			1		1			2		6
Environmental obligations and shutdown (credits) costs			0		3			0		3
Net gain on sales of assets			0					0		(39)
Operating income (loss)			68		(88)			224		210
Interest expense, net			0		0			1		1
Provision for (benefit from) income taxes			0		0			0		0
Total Assets			4,540		5,159			4,540		5,159
Capital expenditures			5		33			16		84
Restructuring Costs and Asset Impairment Charges					(75)					(75)
South America Mines [Member]
Revenues:
Unaffiliated customers			617		425			1,864		1,320
Intersegment			54		13			155		57
Production and delivery			424		344			1,240		1,004
Depreciation, depletion and amortization			134		89			402		236
Impairment of oil and gas properties			0		0			0		0
Metals inventory adjustments			0		0			0		0
Selling, general and administrative expenses			2		1			6		3
Mining exploration and research expenses			0		0			0		0
Environmental obligations and shutdown (credits) costs			0		0			0		0
Net gain on sales of assets			0					0		0
Operating income (loss)			111		4			371		134
Interest expense, net			21		0			63		1
Provision for (benefit from) income taxes			32		2			114		32
Total Assets			10,690		10,979			10,690		10,979
Capital expenditures			39		437			332		1,339
Cerro Verde [Member]
Revenues:
Unaffiliated customers			505		238			1,485		681
Intersegment			54		13			155		64
Production and delivery			333		177			927		540
Depreciation, depletion and amortization			109		57			319		134
Impairment of oil and gas properties			0		0			0		0
Metals inventory adjustments			0		0			0		0
Selling, general and administrative expenses			1		1			5		2
Mining exploration and research expenses			0		0			0		0
Environmental obligations and shutdown (credits) costs			0		0			0		0
Net gain on sales of assets			0					0		0
Operating income (loss)			116		16			389		69
Interest expense, net			21		0			63		1
Provision for (benefit from) income taxes			36		0			126		0
Total Assets			9,139		9,136			9,139		9,136
Capital expenditures			38		421			329		1,296
Other South America Mines [Member]
Revenues:
Unaffiliated customers			112		187			379		639
Intersegment			0		0			0		(7)	[4]
Production and delivery			91		167	[2]		313		464	[3]
Depreciation, depletion and amortization			25		32			83		102
Impairment of oil and gas properties			0		0			0		0
Metals inventory adjustments			0		0			0		0
Selling, general and administrative expenses			1		0			1		1
Mining exploration and research expenses			0		0			0		0
Environmental obligations and shutdown (credits) costs			0		0			0		0
Net gain on sales of assets			0					0		0
Operating income (loss)			(5)		(12)			(18)		65
Interest expense, net			0		0			0		0
Provision for (benefit from) income taxes			(4)		2			(12)		32
Total Assets			1,551		1,843			1,551		1,843
Capital expenditures			1		16			3		43
Restructuring Costs					11					11
Indonesia - Grasberg [Member]
Revenues:
Unaffiliated customers			984	[5]	557	[5]		2,014	[6]	1,969	[6]
Intersegment			2		52			59		37
Production and delivery			478	[2]	417			1,228	[3]	1,311
Depreciation, depletion and amortization			110		90			284		238
Impairment of oil and gas properties			0		0			0		0
Metals inventory adjustments			0		0			0		0
Selling, general and administrative expenses			24		24			60		74
Mining exploration and research expenses			0		0			0		0
Environmental obligations and shutdown (credits) costs			0		0			0		0
Net gain on sales of assets			0					0		0
Operating income (loss)			374		78			501		383
Interest expense, net			0		0			0		0
Provision for (benefit from) income taxes			158		21			212		145
Total Assets			9,830		8,965			9,830		8,965
Capital expenditures			256		222			715		660
Increase (Decrease) in Asset Retirement Obligations			(17)					(17)
Molybdenum mines [Member]
Revenues:
Unaffiliated customers			0		0			0		0
Intersegment			46		83			136		298
Production and delivery			51		83	[2]		147		247	[3]
Depreciation, depletion and amortization			15		26			51		77
Impairment of oil and gas properties			0		0			0		0
Metals inventory adjustments			6		3			12		6
Selling, general and administrative expenses			0		0			0		0
Mining exploration and research expenses			0		0			0		0
Environmental obligations and shutdown (credits) costs			0		0			0		0
Net gain on sales of assets			0					0		0
Operating income (loss)			(26)		(29)			(74)		(32)
Interest expense, net			0		0			0		0
Provision for (benefit from) income taxes			0		0			0		0
Total Assets			1,953		2,017			1,953		2,017
Capital expenditures			1		3			2		10
Restructuring Costs					2					2
Rod & Refining [Member]
Revenues:
Unaffiliated customers			930		946			2,820		3,097
Intersegment			7		5			22		20
Production and delivery			931		946			2,820		3,097
Depreciation, depletion and amortization			2		2			7		7
Impairment of oil and gas properties			0		0			0		0
Metals inventory adjustments			0		0			0		0
Selling, general and administrative expenses			0		0			0		0
Mining exploration and research expenses			0		0			0		0
Environmental obligations and shutdown (credits) costs			0		0			0		0
Net gain on sales of assets			0					0		0
Operating income (loss)			4		3			15		13
Interest expense, net			0		0			0		0
Provision for (benefit from) income taxes			0		0			0		0
Total Assets			238		235			238		235
Capital expenditures			0		1			1		2
Atlantic Copper Smelting & Refining [Member]
Revenues:
Unaffiliated customers			445		438			1,360		1,473
Intersegment			0		1			3		12
Production and delivery			416		410			1,275		1,397
Depreciation, depletion and amortization			7		10			22		29
Impairment of oil and gas properties			0		0			0		0
Metals inventory adjustments			0		0			0		0
Selling, general and administrative expenses			5		4			13		13
Mining exploration and research expenses			0		0			0		0
Environmental obligations and shutdown (credits) costs			0		0			0		0
Net gain on sales of assets			0					0		0
Operating income (loss)			17		15			53		46
Interest expense, net			3		3			11		8
Provision for (benefit from) income taxes			0		0			0		0
Total Assets			565		699			565		699
Capital expenditures			5		10			12		18
Other Mining & Eliminations [Member]
Revenues:
Unaffiliated customers			247	[7]	267	[7]		696	[8]	921	[8]
Intersegment			(966)		(1,100)			(3,088)		(3,617)
Production and delivery			(777)		(873)	[2]		(2,562)		(2,925)	[3]
Depreciation, depletion and amortization			19		16			57		51
Impairment of oil and gas properties			0		0			0		0
Metals inventory adjustments			8		33			9		82
Selling, general and administrative expenses			3		5			9		16
Mining exploration and research expenses			12		25			44		77
Environmental obligations and shutdown (credits) costs			(3)		33			17		57
Net gain on sales of assets			0					(172)		0
Operating income (loss)			19		(72)			206		(54)
Interest expense, net			21		19			60		57
Provision for (benefit from) income taxes			0		0			0		0
Total Assets	[1]		6,170		6,426			6,170		6,426
Capital expenditures			21	[1]	78	[1]		84	[9]	197	[9]
Restructuring Costs					2					2
U.S. Oil & Gas Operations [Member]
Revenues:
Unaffiliated customers			427		525	[10]		1,132		1,594	[11]
Intersegment			0		0			0		0
Production and delivery			231	[12]	293	[12]		1,527	[13]	857	[13]
Depreciation, depletion and amortization			223		450			696		1,465
Impairment of oil and gas properties			238		3,480			4,299		9,270
Metals inventory adjustments			0		0			0		0
Selling, general and administrative expenses			31		37			161	[14]	140
Mining exploration and research expenses			0		0			0		0
Environmental obligations and shutdown (credits) costs			0		0			0		0
Net gain on sales of assets			(7)					(7)		0
Operating income (loss)			(289)		(3,735)			(5,544)		(10,138)
Interest expense, net			102		51			266		129
Provision for (benefit from) income taxes			0		0			0		0
Total Assets			3,462		11,911			3,462		11,911
Capital expenditures			160		635	[15]		1,028	[16]	2,430	[16]
Oil and Gas Drillship settlement/Idle rig costs and inventory write downs			50		21			942		59
Restructuring Costs								38
Corporate, Other & Eliminations [Member]
Revenues:
Unaffiliated customers			0		1			0		1
Intersegment			0		0			0		0
Production and delivery			22	[12]	2	[2]		35	[13]	7	[3]
Depreciation, depletion and amortization			4		4			11		11
Impairment of oil and gas properties			1		172	[17]		18	[18]	172	[18]
Metals inventory adjustments			0		0			0		0
Selling, general and administrative expenses			44		50			155		171
Mining exploration and research expenses			0		0			0		0
Environmental obligations and shutdown (credits) costs			0		1			1		1
Net gain on sales of assets			(7)					(7)		0
Operating income (loss)			(64)		(228)			(213)		(361)
Interest expense, net			39		83			171		240
Provision for (benefit from) income taxes			(304)		(372)			(247)		(1,939)
Total Assets			1,071		272			1,071		272
Capital expenditures			$ 1		47			$ 48		91
Restructuring Costs					2					2
Crude oil and natural gas swaps [Member]
Revenues:
Net mark-to-market gains on derivative contracts					29					87
Pt Smelting [Member]
Segment Reporting Information [Line Items]
Deferred Intercompany Profit, Percentage								25.00%
Equity Method Investment, Ownership Percentage			25.00%					25.00%
Revenues:
Revenues			$ 348		61			$ 912		704
Morocco | Corporate, Other & Eliminations [Member]
Revenues:
Capital expenditures	[17]				37			47		81
Discontinued Operations, Held-for-sale [Member] | Other Mining & Eliminations [Member]
Revenues:
Capital expenditures	[17]		$ 15		$ 69			$ 70		$ 166
Morenci [Member]
Segment Reporting Information [Line Items]
Change in Ownership, Percentage							13.00%
Disposal Group, Disposed of by Sale, Not Discontinued Operations [Member] | Morenci [Member]
Segment Reporting Information [Line Items]
Change in Ownership, Percentage		13.00%
Percentage Of Undivided Interest Owned By Company			72.00%					72.00%				85.00%

[1] Includes (i) assets held for sale totaling $4.7 billion at September 30, 2016, and $4.9 billion at September 30, 2015, and (ii) capital expenditures totaling $15 million in third-quarter 2016 and $69 million in third-quarter 2015 associated with discontinued operations. Refer to Note 2 for a summary of the results of discontinued operations.

[2] Third-quarter 2016 includes asset retirement charges of $17 million at Indonesia mining. Third-quarter 2015 includes asset impairment and restructuring charges totaling $75 million at other North America copper mines, and restructuring charges totaling $11 million at other South America copper mines, $2 million at Molybdenum mines, $2 million at Other Mining & Eliminations and $2 million at Corporate, Other & Eliminations.

[3] The first nine months of 2016 include asset retirement charges of $17 million at Indonesia mining. The first nine months of 2015 includes asset impairment and restructuring charges totaling $75 million at other North America copper mines, and restructuring charges totaling $11 million at other South America copper mines, $2 million at Molybdenum mines, $2 million at Other Mining & Eliminations and $2 million at Corporate, Other & Eliminations.

[4] Reflects net reductions for provisional pricing adjustments to prior period open sales. There were no intersegment sales from El Abra for the first nine months of 2015.

[5] Includes PT-FI’s sales to PT Smelting totaling $348 million in third-quarter 2016 and $61 million in third-quarter 2015.

[6] Includes PT-FI's sales to PT Smelting totaling $912 million for the first nine months of 2016 and $704 million for the first nine months of 2015.

[7] 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.

[8] 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.

[9] Includes capital expenditures of $70 million for the first nine months of 2016 and $166 million for the first nine months of 2015 associated with discontinued operations. Refer to Note 2 for a summary of the results of discontinued operations.

[10] Includes net mark-to-market gains of $29 million associated with crude oil derivative contracts.

[11] Includes net mark-to-market gains of $87 million associated with crude oil derivative contracts.

[12] Includes net charges for oil and gas operations totaling $50 million in third-quarter 2016 and $21 million in third-quarter 2015, primarily for idle rig costs, inventory adjustments, asset impairments and other net charges.

[13] Includes charges for oil and gas operations totaling $942 million for the first nine months of 2016 and $59 million for the first nine months of 2015, primarily for drillship settlement/idle rig costs, inventory adjustments, asset impairments and other net charges.

[14] Includes $38 million for net restructuring-related charges.

[15] Excludes international oil and gas capital expenditures totaling $37 million, primarily related to the Morocco oil and gas properties, which are included in Corporate, Other & Eliminations.

[16] Excludes international oil and gas capital expenditures totaling $47 million for the first nine months of 2016 and $81 million for the first nine months of 2015, primarily related to the Morocco oil and gas properties, which are included in Corporate, Other & Eliminations.

[17] Reflects impairment charges for international oil and gas properties primarily in Morocco.

[18] Reflects impairment charges for international oil and gas properties primarily in Morocco.