Business Segments (Unaudited) (Details) (USD $)	3 Months Ended
	Mar. 31, 2013		Mar. 31, 2012		Dec. 31, 2012	Dec. 31, 2011
Revenues:
Unaffiliated customers	$ 4,583,000,000		$ 4,605,000,000
Intersegment	0		0
Production and delivery	2,719,000,000		2,428,000,000
Depreciation, depletion and amortization	329,000,000		267,000,000
Selling, general and administrative expenses	113,000,000		104,000,000
Exploration and research expenses	52,000,000		62,000,000
Environmental obligations and shutdown costs	15,000,000		10,000,000
Operating income (loss)	1,355,000,000		1,734,000,000
Interest expense, net	57,000,000		63,000,000
Provision for income taxes	428,000,000		491,000,000
Total assets	42,588,000,000		32,905,000,000		35,440,000,000
Capital expenditures	805,000,000		707,000,000
Sales from PT Freeport Indonesia to PT Smelting	430,000,000		589,000,000
Cash and cash equivalents	9,595,000,000		4,496,000,000		3,705,000,000	4,822,000,000
North America Copper Mines Segment [Member]
Revenues:
Unaffiliated customers	129,000,000		30,000,000
Intersegment	1,260,000,000		1,426,000,000
Production and delivery	811,000,000		707,000,000
Depreciation, depletion and amortization	102,000,000		93,000,000
Selling, general and administrative expenses	1,000,000		1,000,000
Exploration and research expenses	0		0
Environmental obligations and shutdown costs	(4,000,000)		0
Operating income (loss)	479,000,000		655,000,000
Interest expense, net	2,000,000		1,000,000
Provision for income taxes	0		0
Total assets	8,506,000,000		7,401,000,000
Capital expenditures	258,000,000		143,000,000
Morenci [Member]
Revenues:
Unaffiliated customers	80,000,000		13,000,000
Intersegment	436,000,000		513,000,000
Production and delivery	297,000,000		256,000,000
Depreciation, depletion and amortization	33,000,000		31,000,000
Selling, general and administrative expenses	0		0
Exploration and research expenses	0		0
Environmental obligations and shutdown costs	0		0
Operating income (loss)	186,000,000		239,000,000
Interest expense, net	1,000,000		0
Provision for income taxes	0		0
Total assets	2,589,000,000		2,146,000,000
Capital expenditures	153,000,000		44,000,000
Other North America Copper Mines [Member]
Revenues:
Unaffiliated customers	49,000,000		17,000,000
Intersegment	824,000,000		913,000,000
Production and delivery	514,000,000		451,000,000
Depreciation, depletion and amortization	69,000,000		62,000,000
Selling, general and administrative expenses	1,000,000		1,000,000
Exploration and research expenses	0		0
Environmental obligations and shutdown costs	(4,000,000)		0
Operating income (loss)	293,000,000		416,000,000
Interest expense, net	1,000,000		1,000,000
Provision for income taxes	0		0
Total assets	5,917,000,000		5,255,000,000
Capital expenditures	105,000,000		99,000,000
South America Mines Segment [Member]
Revenues:
Unaffiliated customers	850,000,000		975,000,000
Intersegment	164,000,000		279,000,000
Production and delivery	475,000,000		463,000,000
Depreciation, depletion and amortization	71,000,000		62,000,000
Selling, general and administrative expenses	1,000,000		2,000,000
Exploration and research expenses	0		0
Environmental obligations and shutdown costs	0		0
Operating income (loss)	467,000,000		727,000,000
Interest expense, net	0		5,000,000
Provision for income taxes	151,000,000		240,000,000
Total assets	10,327,000,000		9,427,000,000
Capital expenditures	226,000,000		152,000,000
Cerro Verde [Member]
Revenues:
Unaffiliated customers	290,000,000		449,000,000
Intersegment	109,000,000		127,000,000
Production and delivery	171,000,000		193,000,000
Depreciation, depletion and amortization	33,000,000		30,000,000
Selling, general and administrative expenses	0		1,000,000
Exploration and research expenses	0		0
Environmental obligations and shutdown costs	0		0
Operating income (loss)	195,000,000		352,000,000
Interest expense, net	0		5,000,000
Provision for income taxes	64,000,000		123,000,000
Total assets	5,968,000,000		5,300,000,000
Capital expenditures	164,000,000		69,000,000
Other South America Mines [Member]
Revenues:
Unaffiliated customers	560,000,000		526,000,000
Intersegment	55,000,000		152,000,000
Production and delivery	304,000,000		270,000,000
Depreciation, depletion and amortization	38,000,000		32,000,000
Selling, general and administrative expenses	1,000,000		1,000,000
Exploration and research expenses	0		0
Environmental obligations and shutdown costs	0		0
Operating income (loss)	272,000,000		375,000,000
Interest expense, net	0		0
Provision for income taxes	87,000,000		117,000,000
Total assets	4,359,000,000		4,127,000,000
Capital expenditures	62,000,000		83,000,000
Indonesia - Grasberg [Member]
Revenues:
Unaffiliated customers	864,000,000	[1]	953,000,000	[1]
Intersegment	67,000,000		(3,000,000)
Production and delivery	563,000,000		515,000,000
Depreciation, depletion and amortization	55,000,000		46,000,000
Selling, general and administrative expenses	26,000,000		33,000,000
Exploration and research expenses	0		0
Environmental obligations and shutdown costs	0		0
Operating income (loss)	287,000,000		356,000,000
Interest expense, net	2,000,000		0
Provision for income taxes	120,000,000		150,000,000
Total assets	6,862,000,000		5,613,000,000
Capital expenditures	191,000,000		182,000,000
Africa - Tenke [Member]
Revenues:
Unaffiliated customers	438,000,000		303,000,000
Intersegment	0		2,000,000
Production and delivery	185,000,000		132,000,000
Depreciation, depletion and amortization	58,000,000		32,000,000
Selling, general and administrative expenses	3,000,000		2,000,000
Exploration and research expenses	0		0
Environmental obligations and shutdown costs	0		0
Operating income (loss)	192,000,000		139,000,000
Interest expense, net	0		0
Provision for income taxes	44,000,000		29,000,000
Total assets	4,894,000,000		4,138,000,000
Capital expenditures	57,000,000		127,000,000
Molybdenum mines [Member]
Revenues:
Unaffiliated customers	0		0
Intersegment	143,000,000		126,000,000
Production and delivery	80,000,000		70,000,000
Depreciation, depletion and amortization	20,000,000		11,000,000
Selling, general and administrative expenses	0		0
Exploration and research expenses	0		0
Environmental obligations and shutdown costs	0		0
Operating income (loss)	43,000,000		45,000,000
Interest expense, net	0		0
Provision for income taxes	0		0
Total assets	2,033,000,000		1,906,000,000
Capital expenditures	40,000,000		93,000,000
Rod & Refining [Member]
Revenues:
Unaffiliated customers	1,330,000,000		1,298,000,000
Intersegment	7,000,000		6,000,000
Production and delivery	1,328,000,000		1,297,000,000
Depreciation, depletion and amortization	3,000,000		2,000,000
Selling, general and administrative expenses	0		0
Exploration and research expenses	0		0
Environmental obligations and shutdown costs	0		0
Operating income (loss)	6,000,000		5,000,000
Interest expense, net	0		0
Provision for income taxes	0		0
Total assets	316,000,000		328,000,000
Capital expenditures	1,000,000		3,000,000
Atlantic Copper Smelting & Refining [Member]
Revenues:
Unaffiliated customers	633,000,000		704,000,000
Intersegment	6,000,000		8,000,000
Production and delivery	628,000,000		695,000,000
Depreciation, depletion and amortization	10,000,000		10,000,000
Selling, general and administrative expenses	5,000,000		5,000,000
Exploration and research expenses	0		0
Environmental obligations and shutdown costs	0		0
Operating income (loss)	(4,000,000)		2,000,000
Interest expense, net	4,000,000		3,000,000
Provision for income taxes	0		0
Total assets	918,000,000		1,033,000,000
Capital expenditures	8,000,000		3,000,000
Corporate, Other & Eliminations [Member]
Revenues:
Unaffiliated customers	339,000,000	[2]	342,000,000	[2]
Intersegment	(1,647,000,000)		(1,844,000,000)
Production and delivery	(1,351,000,000)		(1,451,000,000)
Depreciation, depletion and amortization	10,000,000		11,000,000
Selling, general and administrative expenses	77,000,000		61,000,000
Exploration and research expenses	52,000,000		62,000,000
Environmental obligations and shutdown costs	19,000,000		10,000,000
Operating income (loss)	(115,000,000)		(195,000,000)
Interest expense, net	49,000,000		54,000,000
Provision for income taxes	113,000,000		72,000,000
Total assets	8,732,000,000	[3]	3,059,000,000
Capital expenditures	24,000,000		4,000,000
Parent Company [Member]
Revenues:
Cash and cash equivalents	7,000,000,000
PT Smelting [Member]
Segment Reporting Information [Line Items]
Deferred Intercompany Profit, Percentage	25.00%
Kokkola Cobalt Chemicals Refinery [Member]
Revenues:
Total assets			$ 477,000,000

[1] Included PT Freeport Indonesia’s sales to PT Smelting totaling $430 million in first-quarter 2013 and $589 million in first-quarter 2012.

[2] 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.

[3] Included $7.0 billion of cash and cash equivalents at the parent company and $477 million of total assets related to Freeport Cobalt.