Business Segments (Unaudited) (Details) (USD $) In Millions, unless otherwise specified	3 Months Ended				6 Months Ended
	Jun. 30, 2013		Jun. 30, 2012		Jun. 30, 2013		Jun. 30, 2012		Dec. 31, 2012
Revenues:
Unaffiliated customers	$ 4,288		$ 4,475		$ 8,871		$ 9,080
Intersegment	0		0		0		0
Production and delivery	2,853		2,622		5,572		5,050
Depreciation, depletion and amortization	530		291		859		558
Selling, general and administrative expenses	186		97		299		201
Mining exploration and research expenses	64		73		116		135
Environmental obligations and shutdown costs	16		81		31		91
Operating income (loss)	639		1,311		1,994		3,045
Interest expense, net	132		43		189		106
Provision for income taxes	40		422		468		913
Capital expenditures	1,173		840		1,978		1,547
Total assets	63,157		33,689		63,157		33,689		35,440
Sales from PT Freeport Indonesia to PT Smelting	291		368		721		957
Net income tax benefit resulting from oil and gas acquisitions	183				183
Mining Operations [Member]
Revenues:
Unaffiliated customers	3,951		4,473		8,532		9,076
Intersegment	0		0		0		0
Production and delivery	2,759		2,621		5,475		5,050
Depreciation, depletion and amortization	358		289		685		554
Selling, general and administrative expenses	47		39		92		86
Mining exploration and research expenses	61		73		110		135
Environmental obligations and shutdown costs	16		81		31		91
Operating income (loss)	710		1,370		2,139		3,160
Interest expense, net	41		27		68		56
Provision for income taxes	145		299		460		718
Capital expenditures	973		840		1,770		1,556
Total assets	35,061		31,234		35,061		31,234
North America Copper Mines [Member]
Revenues:
Unaffiliated customers	114		100		239		129
Intersegment	1,195		1,328		2,455		2,753
Production and delivery	853		762		1,652		1,447
Depreciation, depletion and amortization	108		93		210		186
Selling, general and administrative expenses	2		1		3		2
Mining exploration and research expenses	1		0		1		0
Environmental obligations and shutdown costs	(2)		0		(6)		0
Operating income (loss)	347		572		834		1,247
Interest expense, net	3		0		4		0
Provision for income taxes	0		0		0		0
Capital expenditures	286		154		543		296
Total assets	8,498		7,366		8,498		7,366
Morenci [Member]
Revenues:
Unaffiliated customers	38		105		118		118
Intersegment	444		405		880		918
Production and delivery	301		279		598		535
Depreciation, depletion and amortization	37		33		70		64
Selling, general and administrative expenses	1		1		1		1
Mining exploration and research expenses	0		0		0		0
Environmental obligations and shutdown costs	0		0		0		0
Operating income (loss)	143		197		329		436
Interest expense, net	2		0		3		0
Provision for income taxes	0		0		0		0
Capital expenditures	204		52		357		96
Total assets	2,730		2,135		2,730		2,135
Other North America Copper Mines [Member]
Revenues:
Unaffiliated customers	76		(5)		121		11
Intersegment	751		923		1,575		1,835
Production and delivery	552		483		1,054		912
Depreciation, depletion and amortization	71		60		140		122
Selling, general and administrative expenses	1		0		2		1
Mining exploration and research expenses	1		0		1		0
Environmental obligations and shutdown costs	(2)		0		(6)		0
Operating income (loss)	204		375		505		811
Interest expense, net	1		0		1		0
Provision for income taxes	0		0		0		0
Capital expenditures	82		102		186		200
Total assets	5,768		5,231		5,768		5,231
South America Mines [Member]
Revenues:
Unaffiliated customers	764		878		1,614		1,853
Intersegment	187		138		351		417
Production and delivery	516		490		991		953
Depreciation, depletion and amortization	86		72		157		134
Selling, general and administrative expenses	2		1		3		3
Mining exploration and research expenses	0		0		0		0
Environmental obligations and shutdown costs	0		0		0		0
Operating income (loss)	347		453		814		1,180
Interest expense, net	2		0		2		5
Provision for income taxes	127		151		278		391
Capital expenditures	244		240		470		392
Total assets	10,199		9,553		10,199		9,553
Cerro Verde [Member]
Revenues:
Unaffiliated customers	311		332		601		781
Intersegment	86		151		195		278
Production and delivery	189		185		360		378
Depreciation, depletion and amortization	37		33		70		63
Selling, general and administrative expenses	2		0		2		1
Mining exploration and research expenses	0		0		0		0
Environmental obligations and shutdown costs	0		0		0		0
Operating income (loss)	169		265		364		617
Interest expense, net	2		0		2		5
Provision for income taxes	59		96		123		219
Capital expenditures	208		116		372		185
Total assets	6,089		5,472		6,089		5,472
Other South America Mines [Member]
Revenues:
Unaffiliated customers	453		546		1,013		1,072
Intersegment	101		(13)		156		139
Production and delivery	327		305		631		575
Depreciation, depletion and amortization	49		39		87		71
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
Operating income (loss)	178		188		450		563
Interest expense, net	0		0		0		0
Provision for income taxes	68		55		155		172
Capital expenditures	36		124		98		207
Total assets	4,110		4,081		4,110		4,081
Indonesia - Grasberg [Member]
Revenues:
Unaffiliated customers	471	[1]	875	[1]	1,335	[2]	1,828	[2]
Intersegment	120		81		187		78
Production and delivery	563		586		1,126		1,101
Depreciation, depletion and amortization	58		53		113		99
Selling, general and administrative expenses	27		27		53		60
Mining exploration and research expenses	0		0		0		0
Environmental obligations and shutdown costs	0		0		0		0
Operating income (loss)	(57)		290		230		646
Interest expense, net	10		3		12		3
Provision for income taxes	(4)		126		116		276
Capital expenditures	320		205		511		387
Total assets	7,095		5,883		7,095		5,883
Africa - Tenke [Member]
Revenues:
Unaffiliated customers	355		317		793		620
Intersegment	10		5		10		7
Production and delivery	185		152		370		284
Depreciation, depletion and amortization	57		40		115		72
Selling, general and administrative expenses	3		1		6		3
Mining exploration and research expenses	0		0		0		0
Environmental obligations and shutdown costs	0		0		0		0
Operating income (loss)	120		129		312		268
Interest expense, net	2		0		2		0
Provision for income taxes	22		22		66		51
Capital expenditures	46		170		103		297
Total assets	4,887		4,318		4,887		4,318
Molybdenum mines [Member]
Revenues:
Unaffiliated customers	0		0		0		0
Intersegment	144		134		287		260
Production and delivery	78		79		158		149
Depreciation, depletion and amortization	21		12		41		23
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
Operating income (loss)	45		43		88		88
Interest expense, net	0		0		0		0
Provision for income taxes	0		0		0		0
Capital expenditures	42		55		82		148
Total assets	2,061		1,933		2,061		1,933
Rod & Refining [Member]
Revenues:
Unaffiliated customers	1,265		1,283		2,595		2,581
Intersegment	7		7		14		13
Production and delivery	1,262		1,281		2,590		2,578
Depreciation, depletion and amortization	2		3		5		5
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
Operating income (loss)	8		6		14		11
Interest expense, net	0		0		0		0
Provision for income taxes	0		0		0		0
Capital expenditures	1		0		2		3
Total assets	287		327		287		327
Atlantic Copper Smelting & Refining [Member]
Revenues:
Unaffiliated customers	583		686		1,216		1,390
Intersegment	4		9		10		17
Production and delivery	575		669		1,203		1,364
Depreciation, depletion and amortization	12		10		22		20
Selling, general and administrative expenses	4		5		9		10
Mining exploration and research expenses	0		0		0		0
Environmental obligations and shutdown costs	0		0		0		0
Operating income (loss)	(4)		11		(8)		13
Interest expense, net	4		3		8		6
Provision for income taxes	0		0		0		0
Capital expenditures	11		4		19		7
Total assets	934		990		934		990
Other Mining & Eliminations [Member]
Revenues:
Unaffiliated customers	399	[3]	334	[3]	740	[3]	675	[3]
Intersegment	(1,667)		(1,702)		(3,314)		(3,545)
Production and delivery	(1,273)		(1,398)		(2,615)		(2,826)
Depreciation, depletion and amortization	14		6		22		15
Selling, general and administrative expenses	9		4		18		8
Mining exploration and research expenses	60		73		109		135
Environmental obligations and shutdown costs	18		81		37		91
Operating income (loss)	(96)		(134)		(145)		(293)
Interest expense, net	20		21		40		42
Provision for income taxes	0		0		0		0
Capital expenditures	23		12		40		26
Total assets	1,100		864		1,100		864
Oil & Gas Operations [Member]
Revenues:
Unaffiliated customers	336	[4]	0		336	[4]	0
Intersegment	0		0		0		0
Production and delivery	89		0		89		0
Depreciation, depletion and amortization	169		0		169		0
Selling, general and administrative expenses	14		0		14		0
Mining exploration and research expenses	0		0		0		0
Environmental obligations and shutdown costs	0		0		0
Operating income (loss)	64		0		64		0
Interest expense, net	26		0		26		0
Provision for income taxes	0		0		0		0
Capital expenditures	190		0		190		0
Total assets	26,587		0		26,587		0
Corporate, Other & Eliminations [Member]
Revenues:
Unaffiliated customers	1		2		3		4
Intersegment	0		0		0		0
Production and delivery	5		1		8		0
Depreciation, depletion and amortization	3		2		5		4
Selling, general and administrative expenses	125		58		193		115
Mining exploration and research expenses	3		0		6		0
Environmental obligations and shutdown costs	0		0		0		0
Operating income (loss)	(135)		(59)		(209)		(115)
Interest expense, net	65		16		95		50
Provision for income taxes	(105)	[5]	123		8	[5]	195
Capital expenditures	10		0		18		(9)
Total assets	1,509		2,455		1,509		2,455
PT Smelting [Member]
Segment Reporting Information [Line Items]
Deferred Intercompany Profit, Percentage					25.00%
Crude Oil and Natural Gas Swaps [Member]
Revenues:
Unfavorable adjustments to derivative instruments	$ 35	[6]			$ 35	[6]

[1] Included PT Freeport Indonesia’s sales to PT Smelting totaling $291 million in second-quarter 2013 and $368 million in second-quarter 2012.

[2] Included PT Freeport Indonesia’s sales to PT Smelting totaling $721 million for the first six months of 2013 and $957 million for the first six months of 2012.

[3] Included revenues from FCX's molybdenum sales company, which included sales of molybdenum produced by the molybdenum mines and by certain of the North and South America copper mines.

[4] Included unfavorable adjustments of $35 million related to oil and gas derivative instruments. For further discussion, refer to Note 9.

[5] Included $183 million of net benefits resulting from second-quarter 2013 oil and gas acquisitions.

[6] Amounts recorded in revenues.