Business Segments (Unaudited) (Details) (USD $) In Millions, unless otherwise specified	3 Months Ended				6 Months Ended
	Jun. 30, 2012		Jun. 30, 2011		Jun. 30, 2012		Jun. 30, 2011		Dec. 31, 2011
Revenues:
Unaffiliated customers	$ 4,475		$ 5,814		$ 9,080		$ 11,523
Intersegment	0		0		0		0
Production and delivery	2,622		2,557		5,050		4,934
Depreciation, depletion and amortization	291		267		558		499
Selling, general and administrative expenses	97		107		201		221
Exploration and research expenses	73		66		135		116
Environmental obligations and shutdown costs	81		60		91		60
Operating income (loss)	1,311		2,757		3,045		5,693
Interest expense, net	43		74		106		172
Provision for income taxes	422		906		913		1,890
Total assets	33,689		30,579		33,689		30,579		32,070
Capital expenditures	840		527		1,547		1,032
Sales from PT Freeport Indonesia to PT Smelting	368		653		957		1,300
North America Copper Mines Segment [Member]
Revenues:
Unaffiliated customers	100		251		130		403
Intersegment	1,327		1,308		2,753		2,517
Production and delivery	782		671		1,489		1,259
Depreciation, depletion and amortization	94		71		187		129
Selling, general and administrative expenses	1		1		2		2
Exploration and research expenses	0		1		0		1
Environmental obligations and shutdown costs	42		3		42		3
Operating income (loss)	508		812		1,163		1,526
Interest expense, net	1		3		2		5
Provision for income taxes	0		0		0		0
Total assets	7,491		6,767		7,491		6,767
Capital expenditures	154		85		297		204
Morenci [Member]
Revenues:
Unaffiliated customers	105		157		118		293
Intersegment	405		438		918		824
Production and delivery	279		257		535		467
Depreciation, depletion and amortization	33		30		64		58
Selling, general and administrative expenses	1		1		1		1
Exploration and research expenses	0		1		0		1
Environmental obligations and shutdown costs	0		3		0		3
Operating income (loss)	197		303		436		587
Interest expense, net	0		1		0		2
Provision for income taxes	0		0		0		0
Total assets	2,135		1,970		2,135		1,970
Capital expenditures	52		19		96		48
Other North America Copper Mines [Member]
Revenues:
Unaffiliated customers	(5)		94		12		110
Intersegment	922		870		1,835		1,693
Production and delivery	503		414		954		792
Depreciation, depletion and amortization	61		41		123		71
Selling, general and administrative expenses	0		0		1		1
Exploration and research expenses	0		0		0		0
Environmental obligations and shutdown costs	42		0		42		0
Operating income (loss)	311		509		727		939
Interest expense, net	1		2		2		3
Provision for income taxes	0		0		0		0
Total assets	5,356		4,797		5,356		4,797
Capital expenditures	102		66		201		156
South America Mines Segment [Member]
Revenues:
Unaffiliated customers	878		1,236		1,853		2,499
Intersegment	138		212		417		351
Production and delivery	490		441		953		852
Depreciation, depletion and amortization	72		66		134		123
Selling, general and administrative expenses	1		1		3		3
Exploration and research expenses	0		0		0		0
Environmental obligations and shutdown costs	0		0		0		0
Operating income (loss)	453		940		1,180		1,872
Interest expense, net	0		1		5		1
Provision for income taxes	151		321		391		627
Total assets	9,553		8,290		9,553		8,290
Capital expenditures	240		117		392		257
Cerro Verde [Member]
Revenues:
Unaffiliated customers	332		598		781		1,266
Intersegment	151		138		278		198
Production and delivery	185		198		378		373
Depreciation, depletion and amortization	33		36		63		70
Selling, general and administrative expenses	0		1		1		2
Exploration and research expenses	0		0		0		0
Environmental obligations and shutdown costs	0		0		0		0
Operating income (loss)	265		501		617		1,019
Interest expense, net	0		1		5		1
Provision for income taxes	96		159		219		322
Total assets	5,472		4,732		5,472		4,732
Capital expenditures	116		32		185		56
Other South America Mines [Member]
Revenues:
Unaffiliated customers	546		638		1,072		1,233
Intersegment	(13)		74		139		153
Production and delivery	305		243		575		479
Depreciation, depletion and amortization	39		30		71		53
Selling, general and administrative expenses	1		0		2		1
Exploration and research expenses	0		0		0		0
Environmental obligations and shutdown costs	0		0		0		0
Operating income (loss)	188		439		563		853
Interest expense, net	0		0		0		0
Provision for income taxes	55		162		172		305
Total assets	4,081		3,558		4,081		3,558
Capital expenditures	124		85		207		201
Indonesia - Grasberg [Member]
Revenues:
Unaffiliated customers	875	[1]	1,465	[1]	1,828	[2]	2,837	[2]
Intersegment	81		99		78		457
Production and delivery	594		518		1,089		1,044
Depreciation, depletion and amortization	53		60		99		117
Selling, general and administrative expenses	27		28		60		71
Exploration and research expenses	0		0		0		0
Environmental obligations and shutdown costs	0		0		0		0
Operating income (loss)	282		958		658		2,062
Interest expense, net	3		1		3		2
Provision for income taxes	126		405		276		901
Total assets	5,883		5,876		5,883		5,876
Capital expenditures	205		176		387		301
Africa - Tenke [Member]
Revenues:
Unaffiliated customers	317		375		620		684
Intersegment	5		3		7		3
Production and delivery	152		156		284		280
Depreciation, depletion and amortization	40		38		72		66
Selling, general and administrative expenses	1		3		3		5
Exploration and research expenses	0		0		0		0
Environmental obligations and shutdown costs	0		0		0		0
Operating income (loss)	129		181		268		336
Interest expense, net	0		1		0		3
Provision for income taxes	22		40		51		80
Total assets	4,318		3,744		4,318		3,744
Capital expenditures	170		29		297		40
Molybdenum [Member]
Revenues:
Unaffiliated customers	334		413		674		787
Intersegment	0		0		0		0
Production and delivery	277		286		539		526
Depreciation, depletion and amortization	14		16		29		30
Selling, general and administrative expenses	3		4		6		8
Exploration and research expenses	1		1		2		2
Environmental obligations and shutdown costs	0		0		0		0
Operating income (loss)	39		106		98		221
Interest expense, net	0		0		0		0
Provision for income taxes	0		0		0		0
Total assets	2,561		2,193		2,561		2,193
Capital expenditures	58		91		153		162
Rod & Refining [Member]
Revenues:
Unaffiliated customers	1,283		1,421		2,581		2,902
Intersegment	7		6		13		12
Production and delivery	1,281		1,421		2,578		2,902
Depreciation, depletion and amortization	3		2		5		4
Selling, general and administrative expenses	0		0		0		0
Exploration and research expenses	0		0		0		0
Environmental obligations and shutdown costs	0		1		0		1
Operating income (loss)	6		3		11		7
Interest expense, net	0		0		0		0
Provision for income taxes	0		0		0		0
Total assets	327		359		327		359
Capital expenditures	0		2		3		5
Atlantic Copper Smelting & Refining [Member]
Revenues:
Unaffiliated customers	686		651		1,390		1,407
Intersegment	9		2		17		8
Production and delivery	669		685		1,364		1,448
Depreciation, depletion and amortization	10		9		20		19
Selling, general and administrative expenses	5		5		10		13
Exploration and research expenses	0		0		0		0
Environmental obligations and shutdown costs	0		0		0		0
Operating income (loss)	11		(46)		13		(65)
Interest expense, net	3		4		6		8
Provision for income taxes	0		0		0		0
Total assets	990		1,316		990		1,316
Capital expenditures	4		16		7		24
Corporate, Other & Eliminations [Member]
Revenues:
Unaffiliated customers	2		2		4		4
Intersegment	(1,567)		(1,630)		(3,285)		(3,348)
Production and delivery	(1,623)		(1,621)		(3,246)		(3,377)
Depreciation, depletion and amortization	5		5		12		11
Selling, general and administrative expenses	59		65		117		119
Exploration and research expenses	72		64		133		113
Environmental obligations and shutdown costs	39		56		49		56
Operating income (loss)	(117)		(197)		(346)		(266)
Interest expense, net	36		64		90		153
Provision for income taxes	123		140		195		282
Total assets	2,566		2,034		2,566		2,034
Capital expenditures	$ 9		$ 11		$ 11		$ 39

[1] Includes PT Freeport Indonesia’s sales to PT Smelting totaling $368 million in second-quarter 2012 and $653 million in second-quarter 2011.

[2] Includes PT Freeport Indonesia’s sales to PT Smelting totaling $957 million for the first six months of 2012 and $1.3 billion for the first six months of 2011.