DEBT - Components of Debt (Details) - USD ($) $ in Millions	Dec. 31, 2017	Dec. 31, 2016	Dec. 30, 2016	Jun. 30, 2016	May 30, 2016	Nov. 30, 2014	Mar. 31, 2013	Feb. 28, 2012
Debt Instruments [Line Items]
Long-term Debt		$ 2,228
Long-term Debt and Capital Lease Obligations, Including Current Maturities	$ 13,117	16,027
Long-term Debt and Capital Lease Obligations, Repayments of Principal in Next Twelve Months	1,414	1,232
Long-term Debt and Capital Lease Obligations	11,703	14,795
Senior Notes [Member]
Debt Instruments [Line Items]
Long-term Debt	$ 1,200
Senior Notes [Member] | 2.15% Senior Notes due 2017 [Member]
Debt Instruments [Line Items]
Debt Instrument, Interest Rate, Stated Percentage	2.15%							2.15%
Long-term Debt	$ 0	500
Senior Notes [Member] | 2.30% Senior Notes Due 2017
Debt Instruments [Line Items]
Debt Instrument, Interest Rate, Stated Percentage	2.30%					2.30%
Long-term Debt	$ 0	728
Senior Notes [Member] | 2.375% Senior Notes due March 2018 [Member]
Debt Instruments [Line Items]
Debt Instrument, Interest Rate, Stated Percentage	2.375%						2.375%
Long-term Debt	$ 1,408	1,480
Senior Notes [Member] | 6.125% Senior Notes due 2019 [Member]
Debt Instruments [Line Items]
Debt Instrument, Interest Rate, Stated Percentage	6.125%
Long-term Debt	$ 0	186
Senior Notes [Member] | 3.100% Senior Notes due March 2020
Debt Instruments [Line Items]
Debt Instrument, Interest Rate, Stated Percentage	3.10%						3.10%
Long-term Debt	$ 997	996
Senior Notes [Member] | 6.5% Senior Notes due 2020 [Member]
Debt Instruments [Line Items]
Debt Instrument, Interest Rate, Stated Percentage	6.50%
Long-term Debt	$ 0	583
Senior Notes [Member] | 6.625% Senior Notes due 2021 [Member]
Debt Instruments [Line Items]
Debt Instrument, Interest Rate, Stated Percentage	6.625%
Long-term Debt	$ 0	242
Senior Notes [Member] | 4.00% Senior Notes Due 2021 [Member]
Debt Instruments [Line Items]
Debt Instrument, Interest Rate, Stated Percentage	4.00%					4.00%
Long-term Debt	$ 596	595
Senior Notes [Member] | 6.75% Senior Notes due 2022 [Member]
Debt Instruments [Line Items]
Debt Instrument, Interest Rate, Stated Percentage	6.75%
Long-term Debt	$ 427	432
Senior Notes [Member] | 3.55% Senior Notes Due 2022 [Member]
Debt Instruments [Line Items]
Debt Instrument, Interest Rate, Stated Percentage	3.55%							3.55%
Long-term Debt	$ 1,884	1,882
Senior Notes [Member] | 6.875% Senior Notes due 2023 [Member]
Debt Instruments [Line Items]
Debt Instrument, Interest Rate, Stated Percentage	6.875%
Long-term Debt	$ 776	784	$ 785
Senior Notes [Member] | 3.875% Senior Notes due March 2023 [Member]
Debt Instruments [Line Items]
Debt Instrument, Interest Rate, Stated Percentage	3.875%						3.875%
Long-term Debt	$ 1,914	1,912
Senior Notes [Member] | senior notes 4.55 [Member]
Debt Instruments [Line Items]
Debt Instrument, Interest Rate, Stated Percentage	4.55%					4.55%
Long-term Debt	$ 845	844
Senior Notes [Member] | Senior Notes due 2034 5 point 4 percent [Member]
Debt Instruments [Line Items]
Debt Instrument, Interest Rate, Stated Percentage	5.40%					5.40%
Long-term Debt	$ 740	739
Senior Notes [Member] | 5.450% Senior Notes due March 2043 [Member]
Debt Instruments [Line Items]
Debt Instrument, Interest Rate, Stated Percentage	5.45%						5.45%
Long-term Debt	$ 1,842	1,842
Other Debt, Including Capital Leases and Short Term Borrowings [Member]
Debt Instruments [Line Items]
Long-term Debt and Capital Lease Obligations, Including Current Maturities	7	5
Revolving Credit Facility [Member] | Line of Credit [Member]
Debt Instruments [Line Items]
Long-term Debt	0	0
Cerro Verde | Shareholder Loan [Member]
Debt Instruments [Line Items]
Long-term Debt	0	261
Cerro Verde | Line of Credit [Member] | Line of Credit [Member]
Debt Instruments [Line Items]
Long-term Debt	$ 1,269	1,390		$ 1,500	$ 1,275
Freeport-McMoRan Oil & Gas | Senior Notes [Member] | 6.125% Senior Notes due 2019 [Member]
Debt Instruments [Line Items]
Debt Instrument, Interest Rate, Stated Percentage	6.125%
Long-term Debt	$ 0	60
Freeport-McMoRan Oil & Gas | Senior Notes [Member] | 6.5% Senior Notes due 2020 [Member]
Debt Instruments [Line Items]
Debt Instrument, Interest Rate, Stated Percentage	6.50%
Long-term Debt	$ 0	69
Freeport-McMoRan Oil & Gas | Senior Notes [Member] | 6.625% Senior Notes due 2021 [Member]
Debt Instruments [Line Items]
Debt Instrument, Interest Rate, Stated Percentage	6.625%
Long-term Debt	$ 0	35
Freeport-McMoRan Oil & Gas | Senior Notes [Member] | 6.75% Senior Notes due 2022 [Member]
Debt Instruments [Line Items]
Debt Instrument, Interest Rate, Stated Percentage	6.75%
Long-term Debt	$ 0	48
Freeport-McMoRan Oil & Gas | Senior Notes [Member] | 6.875% Senior Notes due 2023 [Member]
Debt Instruments [Line Items]
Debt Instrument, Interest Rate, Stated Percentage	6.875%
Long-term Debt	$ 54	55
Freeport McMoRan Corporation [Member] | Senior Notes [Member] | Senior Notes Due 2031 [Member]
Debt Instruments [Line Items]
Debt Instrument, Interest Rate, Stated Percentage	9.50%
Long-term Debt	$ 127	128
Freeport McMoRan Corporation [Member] | Senior Notes [Member] | Senior Notes Due 2034 [Member]
Debt Instruments [Line Items]
Debt Instrument, Interest Rate, Stated Percentage	6.125%
Long-term Debt	$ 116	116
Freeport McMoRan Corporation [Member] | Debentures [Member] | Debentures Due 2027 [Member]
Debt Instruments [Line Items]
Debt Instrument, Interest Rate, Stated Percentage	7.125%
Long-term Debt	$ 115	$ 115