Business Segments (Unaudited) (Details) - USD ($) $ in Millions			3 Months Ended				6 Months Ended
		May 31, 2016	Jun. 30, 2016		Jun. 30, 2015		Jun. 30, 2016		Jun. 30, 2015		May 30, 2016	Dec. 31, 2015
Revenues:
Unaffiliated customers			$ 3,334		$ 3,938		$ 6,576		$ 7,709
Intersegment			0		0		0		0
Production and delivery			2,956		2,651		5,455		5,330
Depreciation, depletion and amortization			632		833		1,294		1,699
Impairment of oil and gas properties			291		2,686		4,078		5,790
Selling, general and administrative expenses			160		148		298		299
Mining exploration and research expenses			15		30		33		57
Environmental obligations and shutdown costs			11		11		21		24
Net gain on sales of assets			(749)		0		(749)		(39)
Operating income (loss)			18		(2,421)		(3,854)		(5,451)
Interest expense, net			196		142		387		281
Provision for (benefit from) income taxes			116		(699)		193		(1,413)
Total Assets			41,296		54,008		41,296		54,008			$ 46,577
Capital expenditures			833		1,661		1,815		3,528
Restructuring Costs			(37)				39
Disposal Group, Including Discontinued Operation, Assets			4,700		4,900		4,700		4,900
Oil and gas inventory write downs			(2)		(59)		(7)		(63)
Mining Operations [Member]
Revenues:
Unaffiliated customers			2,924	[1]	3,369	[1]	5,871	[2]	6,640	[2]
Intersegment			0	[1]	0	[1]	0	[2]	0	[2]
Production and delivery			2,057	[1]	2,368	[1]	4,146	[2]	4,761	[2]
Depreciation, depletion and amortization			410	[1]	345	[1]	814	[2]	677	[2]
Impairment of oil and gas properties			0	[1]	0	[1]	0	[2]	0	[2]
Selling, general and administrative expenses			32	[1]	37	[1]	57	[2]	75	[2]
Mining exploration and research expenses			15	[1]	30	[1]	33	[2]	57	[2]
Environmental obligations and shutdown costs			10	[1]	11	[1]	20	[2]	24	[2]
Net gain on sales of assets			(749)	[1]			(749)	[2]	(39)	[2]
Operating income (loss)			1,149	[1]	578	[1]	1,550	[2]	1,085	[2]
Interest expense, net			44	[1]	42	[1]	91	[2]	87	[2]
Provision for (benefit from) income taxes			61	[1]	101	[1]	136	[2]	154	[2]
Total Assets	[1]		37,069		38,434		37,069		38,434
Capital expenditures			441	[1]	855	[1]	900	[2]	1,689	[2]
North America Copper Mines [Member]
Revenues:
Unaffiliated customers			122	[1]	272	[1]	340	[2]	493	[2]
Intersegment			938	[1]	1,133	[1]	1,856	[2]	2,247	[2]
Production and delivery			726	[1]	962	[1]	1,514	[2]	1,905	[2]
Depreciation, depletion and amortization			134	[1]	139	[1]	278	[2]	272	[2]
Impairment of oil and gas properties			0	[1]	0	[1]	0	[2]	0	[2]
Selling, general and administrative expenses			2	[1]	2	[1]	3	[2]	3	[2]
Mining exploration and research expenses			0	[1]	2	[1]	1	[2]	5	[2]
Environmental obligations and shutdown costs			0	[1]	0	[1]	0	[2]	0	[2]
Net gain on sales of assets			(577)	[1]			(577)	[2]	(39)	[2]
Operating income (loss)			775	[1]	300	[1]	977	[2]	594	[2]
Interest expense, net			1	[1]	1	[1]	2	[2]	2	[2]
Provision for (benefit from) income taxes			0	[1]	0	[1]	0	[2]	0	[2]
Total Assets	[1]		7,636		9,388		7,636		9,388
Capital expenditures			42	[1]	107	[1]	76	[2]	214	[2]
Morenci [Member]
Revenues:
Unaffiliated customers			79	[1]	180	[1]	241	[2]	286	[2]
Intersegment			404	[1]	427	[1]	761	[2]	877	[2]
Production and delivery			298	[1]	386	[1]	638	[2]	760	[2]
Depreciation, depletion and amortization			57	[1]	55	[1]	119	[2]	106	[2]
Impairment of oil and gas properties			0	[1]	0	[1]	0	[2]	0	[2]
Selling, general and administrative expenses			1	[1]	0	[1]	1	[2]	1	[2]
Mining exploration and research expenses			0	[1]	0	[1]	0	[2]	0	[2]
Environmental obligations and shutdown costs			0	[1]	0	[1]	0	[2]	0	[2]
Net gain on sales of assets			(577)	[1]			(577)	[2]	0	[2]
Operating income (loss)			704	[1]	166	[1]	821	[2]	296	[2]
Interest expense, net			0	[1]	0	[1]	1	[2]	1	[2]
Provision for (benefit from) income taxes			0	[1]	0	[1]	0	[2]	0	[2]
Total Assets	[1]		2,960		3,806		2,960		3,806
Capital expenditures			37	[1]	79	[1]	65	[2]	163	[2]
Other North America Copper Mines [Member]
Revenues:
Unaffiliated customers			43	[1]	92	[1]	99	[2]	207	[2]
Intersegment			534	[1]	706	[1]	1,095	[2]	1,370	[2]
Production and delivery			428	[1]	576	[1],[3]	876	[2]	1,145	[2],[4]
Depreciation, depletion and amortization			77	[1]	84	[1]	159	[2]	166	[2]
Impairment of oil and gas properties			0	[1]	0	[1]	0	[2]	0	[2]
Selling, general and administrative expenses			1	[1]	2	[1]	2	[2]	2	[2]
Mining exploration and research expenses			0	[1]	2	[1]	1	[2]	5	[2]
Environmental obligations and shutdown costs			0	[1]	0	[1]	0	[2]	0	[2]
Net gain on sales of assets			0	[1]			0	[2]	(39)	[2]
Operating income (loss)			71	[1]	134	[1]	156	[2]	298	[2]
Interest expense, net			1	[1]	1	[1]	1	[2]	1	[2]
Provision for (benefit from) income taxes			0	[1]	0	[1]	0	[2]	0	[2]
Total Assets	[1]		4,676		5,582		4,676		5,582
Capital expenditures			5	[1]	28	[1]	11	[2]	51	[2]
Oil and gas inventory write downs					(11)				(11)
South America Mines [Member]
Revenues:
Unaffiliated customers			617	[1]	416	[1]	1,247	[2]	895	[2]
Intersegment			60	[1]	37	[1]	101	[2]	44	[2]
Production and delivery			406	[1]	315	[1]	816	[2]	660	[2]
Depreciation, depletion and amortization			136	[1]	72	[1]	268	[2]	147	[2]
Impairment of oil and gas properties			0	[1]	0	[1]	0	[2]	0	[2]
Selling, general and administrative expenses			2	[1]	1	[1]	4	[2]	2	[2]
Mining exploration and research expenses			0	[1]	0	[1]	0	[2]	0	[2]
Environmental obligations and shutdown costs			0	[1]	0	[1]	0	[2]	0	[2]
Net gain on sales of assets			0	[1]			0	[2]	0	[2]
Operating income (loss)			133	[1]	65	[1]	260	[2]	130	[2]
Interest expense, net			20	[1]	0	[1]	42	[2]	1	[2]
Provision for (benefit from) income taxes			43	[1]	6	[1]	82	[2]	30	[2]
Total Assets	[1]		10,939		10,502		10,939		10,502
Capital expenditures			136	[1]	457	[1]	293	[2]	902	[2]
Cerro Verde [Member]
Revenues:
Unaffiliated customers			494	[1]	195	[1]	980	[2]	443	[2]
Intersegment			60	[1]	37	[1]	101	[2]	51	[2]
Production and delivery			303	[1]	165	[1]	594	[2]	363	[2]
Depreciation, depletion and amortization			109	[1]	40	[1]	210	[2]	77	[2]
Impairment of oil and gas properties			0	[1]	0	[1]	0	[2]	0	[2]
Selling, general and administrative expenses			2	[1]	0	[1]	4	[2]	1	[2]
Mining exploration and research expenses			0	[1]	0	[1]	0	[2]	0	[2]
Environmental obligations and shutdown costs			0	[1]	0	[1]	0	[2]	0	[2]
Net gain on sales of assets			0	[1]			0	[2]	0	[2]
Operating income (loss)			140	[1]	27	[1]	273	[2]	53	[2]
Interest expense, net			20	[1]	0	[1]	42	[2]	1	[2]
Provision for (benefit from) income taxes			45	[1]	(5)	[1]	90	[2]	0	[2]
Total Assets	[1]		9,330		8,567		9,330		8,567
Capital expenditures			135	[1]	444	[1]	291	[2]	875	[2]
Other South America Mines [Member]
Revenues:
Unaffiliated customers			123	[1]	221	[1]	267	[2]	452	[2]
Intersegment			0	[1]	0	[1]	0	[2]	(7)	[2],[5]
Production and delivery			103	[1]	150	[1]	222	[2]	297	[2]
Depreciation, depletion and amortization			27	[1]	32	[1]	58	[2]	70	[2]
Impairment of oil and gas properties			0	[1]	0	[1]	0	[2]	0	[2]
Selling, general and administrative expenses			0	[1]	1	[1]	0	[2]	1	[2]
Mining exploration and research expenses			0	[1]	0	[1]	0	[2]	0	[2]
Environmental obligations and shutdown costs			0	[1]	0	[1]	0	[2]	0	[2]
Net gain on sales of assets			0	[1]			0	[2]	0	[2]
Operating income (loss)			(7)	[1]	38	[1]	(13)	[2]	77	[2]
Interest expense, net			0	[1]	0	[1]	0	[2]	0	[2]
Provision for (benefit from) income taxes			(2)	[1]	11	[1]	(8)	[2]	30	[2]
Total Assets	[1]		1,609		1,935		1,609		1,935
Capital expenditures			1	[1]	13	[1]	2	[2]	27	[2]
Indonesia - Grasberg [Member]
Revenues:
Unaffiliated customers			532	[1],[6]	792	[1],[6]	1,030	[2],[7]	1,413	[2],[7]
Intersegment			(1)	[1],[8]	(2)	[1],[8]	57	[2]	(16)	[2],[5]
Production and delivery			356	[1]	455	[1]	750	[2]	894	[2]
Depreciation, depletion and amortization			93	[1]	78	[1]	174	[2]	148	[2]
Impairment of oil and gas properties			0	[1]	0	[1]	0	[2]	0	[2]
Selling, general and administrative expenses			22	[1]	25	[1]	36	[2]	50	[2]
Mining exploration and research expenses			0	[1]	0	[1]	0	[2]	0	[2]
Environmental obligations and shutdown costs			0	[1]	0	[1]	0	[2]	0	[2]
Net gain on sales of assets			0	[1]			0	[2]	0	[2]
Operating income (loss)			60	[1]	232	[1]	127	[2]	305	[2]
Interest expense, net			0	[1]	0	[1]	0	[2]	0	[2]
Provision for (benefit from) income taxes			18	[1]	95	[1]	54	[2]	124	[2]
Total Assets	[1]		9,550		8,959		9,550		8,959
Capital expenditures			234	[1]	213	[1]	459	[2]	438	[2]
Molybdenum mines [Member]
Revenues:
Unaffiliated customers			0	[1]	0	[1]	0	[2]	0	[2]
Intersegment			45	[1]	102	[1]	90	[2]	215	[2]
Production and delivery			50	[1]	84	[1],[3]	102	[2]	167	[2],[4]
Depreciation, depletion and amortization			17	[1]	25	[1]	36	[2]	51	[2]
Impairment of oil and gas properties			0	[1]	0	[1]	0	[2]	0	[2]
Selling, general and administrative expenses			0	[1]	0	[1]	0	[2]	0	[2]
Mining exploration and research expenses			0	[1]	0	[1]	0	[2]	0	[2]
Environmental obligations and shutdown costs			0	[1]	0	[1]	0	[2]	0	[2]
Net gain on sales of assets			0	[1]			0	[2]	0	[2]
Operating income (loss)			(22)	[1]	(7)	[1]	(48)	[2]	(3)	[2]
Interest expense, net			0	[1]	0	[1]	0	[2]	0	[2]
Provision for (benefit from) income taxes			0	[1]	0	[1]	0	[2]	0	[2]
Total Assets	[1]		1,969		2,052		1,969		2,052
Capital expenditures			0	[1]	4	[1]	1	[2]	7	[2]
Oil and gas inventory write downs					(3)				(3)
Rod & Refining [Member]
Revenues:
Unaffiliated customers			919	[1]	1,089	[1]	1,890	[2]	2,151	[2]
Intersegment			7	[1]	8	[1]	15	[2]	15	[2]
Production and delivery			919	[1]	1,088	[1]	1,889	[2]	2,151	[2]
Depreciation, depletion and amortization			3	[1]	3	[1]	5	[2]	5	[2]
Impairment of oil and gas properties			0	[1]	0	[1]	0	[2]	0	[2]
Selling, general and administrative expenses			0	[1]	0	[1]	0	[2]	0	[2]
Mining exploration and research expenses			0	[1]	0	[1]	0	[2]	0	[2]
Environmental obligations and shutdown costs			0	[1]	0	[1]	0	[2]	0	[2]
Net gain on sales of assets			0	[1]			0	[2]	0	[2]
Operating income (loss)			4	[1]	6	[1]	11	[2]	10	[2]
Interest expense, net			0	[1]	0	[1]	0	[2]	0	[2]
Provision for (benefit from) income taxes			0	[1]	0	[1]	0	[2]	0	[2]
Total Assets	[1]		217		286		217		286
Capital expenditures			0	[1]	0	[1]	1	[2]	1	[2]
Atlantic Copper Smelting & Refining [Member]
Revenues:
Unaffiliated customers			493	[1]	495	[1]	915	[2]	1,035	[2]
Intersegment			2	[1]	5	[1]	3	[2]	11	[2]
Production and delivery			466	[1]	468	[1]	859	[2]	987	[2]
Depreciation, depletion and amortization			7	[1]	9	[1]	15	[2]	19	[2]
Impairment of oil and gas properties			0	[1]	0	[1]	0	[2]	0	[2]
Selling, general and administrative expenses			4	[1]	4	[1]	8	[2]	9	[2]
Mining exploration and research expenses			0	[1]	0	[1]	0	[2]	0	[2]
Environmental obligations and shutdown costs			0	[1]	0	[1]	0	[2]	0	[2]
Net gain on sales of assets			0	[1]			0	[2]	0	[2]
Operating income (loss)			18	[1]	19	[1]	36	[2]	31	[2]
Interest expense, net			4	[1]	2	[1]	8	[2]	5	[2]
Provision for (benefit from) income taxes			0	[1]	0	[1]	0	[2]	0	[2]
Total Assets	[1]		607		786		607		786
Capital expenditures			5	[1]	4	[1]	7	[2]	8	[2]
Other Mining & Eliminations [Member]
Revenues:
Unaffiliated customers			241	[1],[9]	305	[1],[9]	449	[2],[10]	653	[2],[10]
Intersegment			(1,051)	[1]	(1,283)	[1]	(2,122)	[2]	(2,516)	[2]
Production and delivery			(866)	[1]	(1,004)	[1],[3]	(1,784)	[2]	(2,003)	[2],[4]
Depreciation, depletion and amortization			20	[1]	19	[1]	38	[2]	35	[2]
Impairment of oil and gas properties			0	[1]	0	[1]	0	[2]	0	[2]
Selling, general and administrative expenses			2	[1]	5	[1]	6	[2]	11	[2]
Mining exploration and research expenses			15	[1]	28	[1]	32	[2]	52	[2]
Environmental obligations and shutdown costs			10	[1]	11	[1]	20	[2]	24	[2]
Net gain on sales of assets			(172)	[1]			(172)	[2]	0	[2]
Operating income (loss)			181	[1]	(37)	[1]	187	[2]	18	[2]
Interest expense, net			19	[1]	39	[1]	39	[2]	79	[2]
Provision for (benefit from) income taxes			0	[1]	0	[1]	0	[2]	0	[2]
Total Assets	[1],[11]		6,151		6,461		6,151		6,461
Capital expenditures			24	[1],[12]	70	[1],[12]	63	[2],[13]	119	[2],[13]
Oil and gas inventory write downs					(45)				(49)
U.S. Oil & Gas Operations [Member]
Revenues:
Unaffiliated customers			410		569	[14]	705		1,069	[15]
Intersegment			0		0		0		0
Production and delivery			889	[16]	281	[16]	1,296	[17]	564	[17]
Depreciation, depletion and amortization			218		485		473		1,015
Impairment of oil and gas properties			290		2,686		4,061		5,790
Selling, general and administrative expenses			81	[18]	49		130	[19]	103
Mining exploration and research expenses			0		0		0		0
Environmental obligations and shutdown costs			0		0		0		0
Net gain on sales of assets			0				0		0
Operating income (loss)			(1,068)		(2,932)		(5,255)		(6,403)
Interest expense, net			93		41		164		78
Provision for (benefit from) income taxes			0		0		0		0
Total Assets			3,902		15,393		3,902		15,393
Capital expenditures			388	[20]	777	[20]	868	[21]	1,795	[21]
Oil and Gas Drillship settlement/Idle rig costs and inventory write downs			(692)		(22)		(892)		(39)
Corporate, Other & Eliminations [Member]
Revenues:
Unaffiliated customers			0		0		0		0
Intersegment			0		0		0		0
Production and delivery			10		2		13		5
Depreciation, depletion and amortization			4		3		7		7
Impairment of oil and gas properties			1	[22]	0		17	[23]	0
Selling, general and administrative expenses			47		62		111		121
Mining exploration and research expenses			0		0		0		0
Environmental obligations and shutdown costs			1		0		1		0
Net gain on sales of assets			0				0		0
Operating income (loss)			(63)		(67)		(149)		(133)
Interest expense, net			59		59		132		116
Provision for (benefit from) income taxes			55		(800)		57		(1,567)
Total Assets			325		181		325		181
Capital expenditures			$ 4		29		$ 47		44
Crude oil and natural gas swaps [Member]
Revenues:
Net mark-to-market gains on derivative contracts					6				58
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			$ 287		293		$ 564		643
Morocco | Corporate, Other & Eliminations [Member]
Revenues:
Capital expenditures	[20]		4		29		47		44
Discontinued Operations, Held-for-sale [Member] | Other Mining & Eliminations [Member]
Revenues:
Capital expenditures	[20]		$ 20		$ 58		$ 55		$ 97
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] Excludes the results of Tenke, which is reported as discontinued operations (refer to Note 2).

[2] Excludes the results of Tenke, which is reported as discontinued operations (refer to Note 2).

[3] Includes inventory adjustments totaling $11 million at other North America copper mines, $3 million at Molybdenum mines and $45 million at Other Mining & Eliminations.

[4] Includes inventory adjustments totaling $11 million at other North America copper mines, $3 million at Molybdenum mines and $49 million at Other Mining & Eliminations for the first six months of 2015.

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

[6] Includes PT-FI’s sales to PT Smelting totaling $287 million in second-quarter 2016 and $293 million in second-quarter 2015.

[7] Includes PT-FI's sales to PT Smelting totaling $564 million for the first six months of 2016 and $643 million for the first six months of 2015.

[8] Reflects net reductions for provisional pricing adjustments to prior period open sales. There were no intersegment sales from Grasberg in second-quarter 2016 or 2015.

[9] 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.

[10] 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.

[11] Includes assets held for sale totaling $4.7 billion at June 30, 2016 and $4.9 billion at June 30, 2015, associated with discontinued operations (refer to Note 2).

[12] Includes capital expenditures of $20 million in second-quarter 2016 and $58 million in second-quarter 2015 associated with discontinued operations.

[13] Includes capital expenditures of $55 million for the first six months of 2016 and $97 million for the first six months of 2015 associated with discontinued operations.

[14] Includes net mark-to-market gains of $6 million associated with crude oil derivative contracts.

[15] Includes net mark-to-market gains of $58 million associated with crude oil derivative contracts.

[16] Includes charges at oil and gas operations totaling $692 million in second-quarter 2016 and $22 million in second-quarter 2015, primarily associated with drillship settlement/idle rig costs and inventory write-downs.

[17] Includes charges at oil and gas operations totaling $892 million for the first six months of 2016 and $39 million for the first six months of 2015, primarily associated with drillship settlement/idle rig costs and inventory write downs.

[18] Includes $37 million for net restructuring charges.

[19] Includes $39 million for net restructuring charges.

[20] Excludes international oil and gas capital expenditures totaling $4 million in second-quarter 2016 and $29 million in second-quarter 2015, primarily related to the Morocco oil and gas properties, which are included in Corporate, Other & Eliminations.

[21] Excludes international oil and gas capital expenditures totaling $47 million for the first six months of 2016 and $44 million for the first six months of 2015, primarily related to the Morocco oil and gas properties, which are included in Corporate, Other & Eliminations.

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

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