Guarantor Financial Statements (Unaudited) Condensed Consolidating Statements of Comprehensive Income (Loss) (Details) - USD ($) $ in Millions	3 Months Ended		9 Months Ended
	Sep. 30, 2017	Sep. 30, 2016	Sep. 30, 2017	Sep. 30, 2016
Revenues	$ 4,310	$ 3,877	$ 11,362	$ 10,453
Total costs and expenses	3,393	3,518	9,196	13,948
Operating (loss) income	917	359	2,166	(3,495)
Interest expense, net	(304)	(187)	(633)	(574)
Other income (expense), net	13	5	44	105
Income (loss) from continuing operations before income taxes and equity in affiliated companies’ net earnings	626	177	1,577	(3,964)
(Provision for) benefit from income taxes	(387)	114	(747)	(79)
Equity in affiliated companies’ net earnings (losses)	3	1	6	9
Net income (loss) from continuing operations	242	292	836	(4,034)
Net income (loss) from discontinued operations	3	(6)	50	(191)
Net income (loss)	245	286	886	(4,225)
Continuing operations	35	(47)	(106)	(177)
Discontinued operations	0	(22)	(4)	(44)
Net income (loss) attributable to common stockholders	280	217	776	(4,446)
Other comprehensive income (loss)	13	12	105	27
Total comprehensive income (loss)	293	229	881	(4,419)
Eliminations [Member]
Revenues	0	0	0	0
Total costs and expenses	(1)	1	11	7
Operating (loss) income	1	(1)	(11)	(7)
Interest expense, net	89	89	252	237
Other income (expense), net	(89)	(76)	(252)	(202)
Income (loss) from continuing operations before income taxes and equity in affiliated companies’ net earnings	1	12	(11)	28
(Provision for) benefit from income taxes	0	8	4	2
Equity in affiliated companies’ net earnings (losses)	(283)	883	(907)	10,733
Net income (loss) from continuing operations	(282)	903	(914)	10,763
Net income (loss) from discontinued operations	0	(12)	0	(33)
Net income (loss)	(282)	891	(914)	10,730
Continuing operations	(34)	(23)	(64)	(36)
Discontinued operations	0	0	0	0
Net income (loss) attributable to common stockholders	(316)	868	(978)	10,694
Other comprehensive income (loss)	(13)	(12)	(105)	(27)
Total comprehensive income (loss)	(329)	856	(1,083)	10,667
FCX Issuer [Member] | Reportable Legal Entities [Member]
Revenues	0	0	0	0
Total costs and expenses	8	12	31	56
Operating (loss) income	(8)	(12)	(31)	(56)
Interest expense, net	(116)	(126)	(355)	(404)
Other income (expense), net	97	91	256	248
Income (loss) from continuing operations before income taxes and equity in affiliated companies’ net earnings	(27)	(47)	(130)	(212)
(Provision for) benefit from income taxes	21	343	(111)	(1,785)
Equity in affiliated companies’ net earnings (losses)	286	(75)	1,017	(2,450)
Net income (loss) from continuing operations	280	221	776	(4,447)
Net income (loss) from discontinued operations	0	(4)	0	1
Net income (loss)	280	217	776	(4,446)
Continuing operations	0	0	0	0
Discontinued operations	0	0	0	0
Net income (loss) attributable to common stockholders	280	217	776	(4,446)
Other comprehensive income (loss)	13	12	105	27
Total comprehensive income (loss)	293	229	881	(4,419)
FM O&G LLC Guarantor [Member]
Production Related Impairments or Charges		95		1,500
FM O&G LLC Guarantor [Member] | Reportable Legal Entities [Member]
Revenues	13	110	38	294
Total costs and expenses	25	266	86	2,859
Operating (loss) income	(12)	(156)	(48)	(2,565)
Interest expense, net	(59)	(18)	(167)	(37)
Other income (expense), net	3	0	3	0
Income (loss) from continuing operations before income taxes and equity in affiliated companies’ net earnings	(68)	(174)	(212)	(2,602)
(Provision for) benefit from income taxes	24	(197)	74	725
Equity in affiliated companies’ net earnings (losses)	20	(218)	14	(3,202)
Net income (loss) from continuing operations	(24)	(589)	(124)	(5,079)
Net income (loss) from discontinued operations	0	0	0	0
Net income (loss)	(24)	(589)	(124)	(5,079)
Continuing operations	0	0	0	0
Discontinued operations	0	0	0	0
Net income (loss) attributable to common stockholders	(24)	(589)	(124)	(5,079)
Other comprehensive income (loss)	0	0	0	0
Total comprehensive income (loss)	(24)	(589)	(124)	(5,079)
Non-Guarantor Subsidiaries [Member]
Production Related Impairments or Charges		200		2,800
Non-Guarantor Subsidiaries [Member] | Reportable Legal Entities [Member]
Revenues	4,297	3,767	11,324	10,159
Total costs and expenses	3,361	3,239	9,068	11,026
Operating (loss) income	936	528	2,256	(867)
Interest expense, net	(218)	(132)	(363)	(370)
Other income (expense), net	2	(10)	37	59
Income (loss) from continuing operations before income taxes and equity in affiliated companies’ net earnings	720	386	1,930	(1,178)
(Provision for) benefit from income taxes	(432)	(40)	(714)	979
Equity in affiliated companies’ net earnings (losses)	(20)	(589)	(118)	(5,072)
Net income (loss) from continuing operations	268	(243)	1,098	(5,271)
Net income (loss) from discontinued operations	3	10	50	(159)
Net income (loss)	271	(233)	1,148	(5,430)
Continuing operations	69	(24)	(42)	(141)
Discontinued operations	0	(22)	(4)	(44)
Net income (loss) attributable to common stockholders	340	(279)	1,102	(5,615)
Other comprehensive income (loss)	13	12	105	27
Total comprehensive income (loss)	$ 353	$ (267)	$ 1,207	$ (5,588)