BUSINESS SEGMENTS (Segment Reporting) (Details) (USD $) In Millions, unless otherwise specified	3 Months Ended									12 Months Ended
	Dec. 31, 2011		Sep. 30, 2011	Jun. 30, 2011	Mar. 31, 2011	Dec. 31, 2010	Sep. 30, 2010	Jun. 30, 2010	Mar. 31, 2010	Dec. 31, 2011		Dec. 31, 2010		Dec. 31, 2009
Revenues:
Unaffiliated customers	$ 4,162		$ 5,195	$ 5,814	$ 5,709	$ 5,603	$ 5,152	$ 3,864	$ 4,363	$ 20,880	[1]	$ 18,982	[1]	$ 15,040	[1]
Intersegment
Production and delivery										9,898		8,335		7,006
Depreciation, depletion and amortization										1,022		1,036		1,014
Selling, general and administrative expenses										415		381		321
Exploration and research expenses										271		143		90
Environmental and shutdown expenses										134		19		106	[2]
Operating income (loss)	1,297	[3]	2,150	2,757	2,936	3,097	2,499	1,424	2,048	9,140	[3]	9,068		6,503
Interest expense, net										312		462		586
Provision for (benefit from) income taxes										3,087		2,983		2,307
Total assets	32,070					29,386				32,070		29,386		25,996
Capital expenditures										2,534		1,412		1,587
Start up costs associated with Tenke Fungurume's project														50
Restructuring Charges														23
North America Copper Mines [Member] | Morenci [Member]
Revenues:
Unaffiliated customers										418		59		68
Intersegment										1,697		1,465		1,074
Production and delivery										984		691		623
Depreciation, depletion and amortization										116		134		142
Selling, general and administrative expenses										2
Exploration and research expenses										7
Environmental and shutdown expenses										4				26	[2]
Operating income (loss)										1,002		699		351
Interest expense, net										2		4		3
Provision for (benefit from) income taxes
Total assets	2,006					1,940				2,006		1,940		1,934
Capital expenditures										95		47		46
North America Copper Mines [Member] | Other North America Mines [Member]
Revenues:
Unaffiliated customers										180		52		94
Intersegment										3,338		2,597		2,028
Production and delivery										1,645		1,361		1,288
Depreciation, depletion and amortization										163		139		138
Selling, general and administrative expenses										2
Exploration and research expenses
Environmental and shutdown expenses										(15)				27	[2]
Operating income (loss)										1,723		1,149		669
Interest expense, net										6		10		12
Provision for (benefit from) income taxes
Total assets	5,086					4,477				5,086		4,477		4,207
Capital expenditures										400		186		299
North America Copper Mines [Member] | Total North America Mines [Member]
Revenues:
Unaffiliated customers										598		111		162
Intersegment										5,035		4,062		3,102
Production and delivery										2,629		2,052		1,911
Depreciation, depletion and amortization										279		273		280
Selling, general and administrative expenses										4
Exploration and research expenses										7
Environmental and shutdown expenses										(11)				53	[2]
Operating income (loss)										2,725		1,848		1,020
Interest expense, net										8		14		15
Provision for (benefit from) income taxes
Total assets	7,092					6,417				7,092		6,417		6,141
Capital expenditures										495		233		345
South America [Member] | Cerro Verde [Member]
Revenues:
Unaffiliated customers										2,115		1,957		1,491
Intersegment										417		453		286
Production and delivery										827		705		648
Depreciation, depletion and amortization										135		148		153
Selling, general and administrative expenses										4
Exploration and research expenses
Environmental and shutdown expenses															[2]
Operating income (loss)										1,566		1,557		976
Interest expense, net										1
Provision for (benefit from) income taxes										553		516		313
Total assets	5,110					4,272				5,110		4,272		3,937
Capital expenditures										198		106		103
South America [Member] | Other South America Mines [Member]
Revenues:
Unaffiliated customers										2,457		2,449		1,950
Intersegment										269		132		112
Production and delivery										1,078		973		915
Depreciation, depletion and amortization										123		102		122
Selling, general and administrative expenses										3
Exploration and research expenses
Environmental and shutdown expenses															[2]
Operating income (loss)										1,522		1,506		1,025
Interest expense, net														2
Provision for (benefit from) income taxes										522		483		337
Total assets	3,604					3,263				3,604		3,263		2,515
Capital expenditures										405		364		61
South America [Member] | Total South America Mines [Member]
Revenues:
Unaffiliated customers										4,572		4,406		3,441
Intersegment										686		585		398
Production and delivery										1,905		1,678		1,563
Depreciation, depletion and amortization										258		250		275
Selling, general and administrative expenses										7
Exploration and research expenses
Environmental and shutdown expenses															[2]
Operating income (loss)										3,088		3,063		2,001
Interest expense, net										1				2
Provision for (benefit from) income taxes										1,075		999		650
Total assets	8,714					7,535				8,714		7,535		6,452
Capital expenditures										603		470		164
Indonesia - Grasberg [Member]
Revenues:
Unaffiliated customers										4,504	[4]	5,230	[4]	4,972	[5]
Intersegment										542		1,147		936
Production and delivery										1,902		1,904		1,505
Depreciation, depletion and amortization										215		257		275
Selling, general and administrative expenses										124		117		94
Exploration and research expenses
Environmental and shutdown expenses															[2]
Operating income (loss)										2,805		4,099		4,034
Interest expense, net										8				(3)
Provision for (benefit from) income taxes										1,256		1,709		1,697
Total assets	5,349					6,048				5,349		6,048		4,974
Capital expenditures										648		436		266
Africa - Tenke [Member]
Revenues:
Unaffiliated customers										1,282		1,106		389
Intersegment										7
Production and delivery										591		488		315	[6]
Depreciation, depletion and amortization										140		128		66
Selling, general and administrative expenses										8
Exploration and research expenses
Environmental and shutdown expenses															[2]
Operating income (loss)										550		490		8
Interest expense, net										6		5		10
Provision for (benefit from) income taxes										120		118		(15)
Total assets	3,890					3,640				3,890		3,640		3,386
Capital expenditures										193		100		659
Molybdenum [Member]
Revenues:
Unaffiliated customers										1,424		1,205		847
Production and delivery										1,036		784		660
Depreciation, depletion and amortization										60		51		49
Selling, general and administrative expenses										15		11		11
Exploration and research expenses										3		2		2
Environmental and shutdown expenses														(1)	[2]
Operating income (loss)										310		357		126
Interest expense, net
Provision for (benefit from) income taxes
Total assets	2,434					1,897				2,434		1,897		1,731
Capital expenditures										461		89		82
Rod & Refining [Member]
Revenues:
Unaffiliated customers										5,523		4,444		3,328
Intersegment										26		26		28
Production and delivery										5,527		4,442		3,336
Depreciation, depletion and amortization										8		8		8
Selling, general and administrative expenses
Exploration and research expenses
Environmental and shutdown expenses										1		1		(2)	[2]
Operating income (loss)										13		19		14
Interest expense, net
Provision for (benefit from) income taxes
Total assets	259					311				259		311		291
Capital expenditures										10		7		9
Atlantic Copper Smelting & Refining [Member]
Revenues:
Unaffiliated customers										2,969		2,473		1,892
Intersegment										15		18
Production and delivery										2,991		2,470		1,895
Depreciation, depletion and amortization										40		38		36
Selling, general and administrative expenses										22		20		17
Exploration and research expenses
Environmental and shutdown expenses															[2]
Operating income (loss)										(69)		(37)		(56)
Interest expense, net										15		10		5
Provision for (benefit from) income taxes
Total assets	1,109					1,317				1,109		1,317		991
Capital expenditures										32		28		31
Corporate, Other & Eliminations [Member]
Revenues:
Unaffiliated customers										8		7		9
Intersegment										(6,311)		(5,838)		(4,464)
Production and delivery										(6,683)		(5,483)		(4,179)
Depreciation, depletion and amortization										22		31		25
Selling, general and administrative expenses										235		233		199
Exploration and research expenses										261		141		88
Environmental and shutdown expenses										144		18		56	[2]
Operating income (loss)										(282)		(771)		(644)
Interest expense, net										274		433		557
Provision for (benefit from) income taxes										636		157		(25)
Total assets	3,223					2,221				3,223		2,221		2,030
Capital expenditures										92		49		31
PT Smelting [Member]
Segment Reporting Information [Line Items]
Sales PT Smelting										$ 2,300		$ 2,300		$ 1,900

[1] Revenues are attributed to countries based on the location of the customer.

[2] Includes charges totaling $23 million associated with net restructuring charges, primarily at the Morenci mine

[3] Includes charges totaling $116 million ($50 million to net income attributable to common stock or $0.05 per share) for the fourth quarter and the year primarily associated with bonuses for new labor agreements and other employee costs at PT Freeport Indonesia, Cerro Verde and El Abra.

[4] Includes PT Freeport Indonesia's sales to PT Smelting totaling $2.3 billion in 2011 and 2010.

[5] Includes PT Freeport Indonesia's sales to PT Smelting totaling $1.9 billion.

[6] Includes charges totaling $50 million associated with Tenke Fungurume's project start-up costs