Contractual interest rate for funds borrowed, under the debt agreement.

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- Definition

Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table.

+ References

No definition available.

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- Definition

Period of time between issuance and maturity of debt instrument, in PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days.

+ References

No definition available.

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- Definition

The carrying value as of the balance sheet date of the current and noncurrent portions of long-term obligations drawn from a line of credit, which is a bank's commitment to make loans up to a specific amount. Examples of items that might be included in the application of this element may consist of letters of credit, standby letters of credit, and revolving credit arrangements, under which borrowings can be made up to a maximum amount as of any point in time conditional on satisfaction of specified terms before, as of and after the date of drawdowns on the line. Includes short-term obligations that would normally be classified as current liabilities but for which (a) postbalance sheet date issuance of a long term obligation to refinance the short term obligation on a long term basis, or (b) the enterprise has entered into a financing agreement that clearly permits the enterprise to refinance the short-term obligation on a long term basis and the following conditions are met (1) the agreement does not expire within 1 year and is not cancelable by the lender except for violation of an objectively determinable provision, (2) no violation exists at the BS date, and (3) the lender has entered into the financing agreement is expected to be financially capable of honoring the agreement.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
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-Section S99
-Paragraph 1
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- Definition

Maximum borrowing capacity under the credit facility without consideration of any current restrictions on the amount that could be borrowed or the amounts currently outstanding under the facility.

+ References

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- Definition

Amount of borrowing capacity currently available under the credit facility (current borrowing capacity less the amount of borrowings outstanding).

+ References

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- Definition

Amount, after unamortized (discount) premium and debt issuance costs, of long-term debt. Includes, but not limited to, notes payable, bonds payable, debentures, mortgage loans and commercial paper. Excludes capital lease obligations.

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 470
-SubTopic 20
-Section 50
-Paragraph 4
-Subparagraph (b)(3)
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- Definition

Amount, after unamortized (discount) premium and debt issuance costs, of long-term debt, classified as current. Includes, but not limited to, notes payable, bonds payable, debentures, mortgage loans and commercial paper. Excludes capital lease obligations.

+ References

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- Definition

Amount after unamortized (discount) premium and debt issuance costs of long-term debt classified as noncurrent and excluding amounts to be repaid within one year or the normal operating cycle, if longer. Includes, but not limited to, notes payable, bonds payable, debentures, mortgage loans and commercial paper. Excludes capital lease obligations.

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DEBT - Components of Debt (Details) - USD ($)		9 Months Ended
DEBT - Components of Debt (Details) - USD ($)	May 02, 2019	Sep. 30, 2014	Dec. 31, 2020	Jul. 31, 2020	Jun. 30, 2020	Mar. 31, 2020	Dec. 31, 2019	Aug. 15, 2019	Aug. 01, 2019
Debt Instruments [Line Items]
Long-term Debt			$ 9,711,000,000				$ 9,826,000,000
Long-term Debt and Capital Lease Obligations, Repayments of Principal in Next Twelve Months			(34,000,000)				(5,000,000)
Long-term debt			$ 9,677,000,000				$ 9,821,000,000
Term of Debt Agreement	5 years
4.00% Senior Notes Due 2021 [Member]
Debt Instruments [Line Items]
Debt Instrument, Interest Rate, Stated Percentage						4.00%			4.00%
3.55% Senior Notes Due 2022 [Member]
Debt Instruments [Line Items]
Debt Instrument, Interest Rate, Stated Percentage						3.55%			3.55%
6.875% Senior Notes due 2023 [Member]
Debt Instruments [Line Items]
Debt Instrument, Interest Rate, Stated Percentage									6.875%
senior notes 4.55 [Member]
Debt Instruments [Line Items]
Debt Instrument, Interest Rate, Stated Percentage								4.55%
Senior Notes due 2027, 5% [Member]
Debt Instruments [Line Items]
Debt Instrument, Interest Rate, Stated Percentage				4.375%					5.00%
Long-term Debt				$ 650,000,000
Senior Notes due 2029, 5.25% [Member]
Debt Instruments [Line Items]
Debt Instrument, Interest Rate, Stated Percentage				4.625%					5.25%
Long-term Debt				$ 850,000,000
Senior Notes Due 2028, 4.125% [Member]
Debt Instruments [Line Items]
Debt Instrument, Interest Rate, Stated Percentage						4.125%
Senior Notes Due 2030, 4.25%
Debt Instruments [Line Items]
Debt Instrument, Interest Rate, Stated Percentage						4.25%
Senior Notes [Member] \| 2.15% Senior Notes due 2017 [Member]
Debt Instruments [Line Items]
Debt Instrument, Interest Rate, Stated Percentage			2.15%
Senior Notes [Member] \| 2.30% Senior Notes Due 2017
Debt Instruments [Line Items]
Debt Instrument, Interest Rate, Stated Percentage			2.30%
Senior Notes [Member] \| 2.375% Senior Notes due March 2018 [Member]
Debt Instruments [Line Items]
Debt Instrument, Interest Rate, Stated Percentage			2.375%
Senior Notes [Member] \| 6.125% Senior Notes due 2019 [Member]
Debt Instruments [Line Items]
Debt Instrument, Interest Rate, Stated Percentage			6.125%				6.125%
Senior Notes [Member] \| 3.100% Senior Notes due March 2020
Debt Instruments [Line Items]
Debt Instrument, Interest Rate, Stated Percentage			3.10%
Senior Notes [Member] \| 6.5% Senior Notes due 2020 [Member]
Debt Instruments [Line Items]
Debt Instrument, Interest Rate, Stated Percentage			6.50%				6.50%
Senior Notes [Member] \| 6.625% Senior Notes due 2021 [Member]
Debt Instruments [Line Items]
Debt Instrument, Interest Rate, Stated Percentage			6.625%				6.625%
Senior Notes [Member] \| 4.00% Senior Notes Due 2021 [Member]
Debt Instruments [Line Items]
Debt Instrument, Interest Rate, Stated Percentage			4.00%
Long-term Debt			$ 0				$ 194,000,000
Senior Notes [Member] \| 6.75% Senior Notes due 2022 [Member]
Debt Instruments [Line Items]
Debt Instrument, Interest Rate, Stated Percentage			6.75%				6.75%
Senior Notes [Member] \| 3.55% Senior Notes Due 2022 [Member]
Debt Instruments [Line Items]
Debt Instrument, Interest Rate, Stated Percentage			3.55%
Long-term Debt			$ 523,000,000				$ 1,876,000,000
Senior Notes [Member] \| 6.875% Senior Notes due 2023 [Member]
Debt Instruments [Line Items]
Debt Instrument, Interest Rate, Stated Percentage			6.875%				6.875%
Senior Notes [Member] \| 3.875% Senior Notes due March 2023 [Member]
Debt Instruments [Line Items]
Debt Instrument, Interest Rate, Stated Percentage			3.875%
Long-term Debt			$ 994,000,000				$ 1,917,000,000
Senior Notes [Member] \| senior notes 4.55 [Member]
Debt Instruments [Line Items]
Debt Instrument, Interest Rate, Stated Percentage			4.55%
Long-term Debt			$ 728,000,000				846,000,000
Senior Notes [Member] \| Senior Notes due 2027, 5% [Member]
Debt Instruments [Line Items]
Debt Instrument, Interest Rate, Stated Percentage			5.00%
Long-term Debt			$ 593,000,000				592,000,000
Senior Notes [Member] \| Senior Notes due 2029, 5.25% [Member]
Debt Instruments [Line Items]
Debt Instrument, Interest Rate, Stated Percentage			5.25%
Long-term Debt			$ 593,000,000				592,000,000
Senior Notes [Member] \| Senior Notes due 2034 5 point 4 percent [Member]
Debt Instruments [Line Items]
Debt Instrument, Interest Rate, Stated Percentage			5.40%
Long-term Debt			$ 742,000,000				741,000,000
Senior Notes [Member] \| 5.450% Senior Notes due March 2043 [Member]
Debt Instruments [Line Items]
Debt Instrument, Interest Rate, Stated Percentage			5.45%
Long-term Debt			$ 1,845,000,000				1,844,000,000
Senior Notes [Member] \| Senior Notes Due 2028, 4.125% [Member]
Debt Instruments [Line Items]
Debt Instrument, Interest Rate, Stated Percentage			4.125%
Long-term Debt			$ 691,000,000				0
Senior Notes [Member] \| Senior Notes Due 2028, 4.375%
Debt Instruments [Line Items]
Debt Instrument, Interest Rate, Stated Percentage			4.375%
Long-term Debt			$ 642,000,000				0
Senior Notes [Member] \| Senior Notes Due 2030, 4.25%
Debt Instruments [Line Items]
Debt Instrument, Interest Rate, Stated Percentage			4.25%
Long-term Debt			$ 592,000,000				0
Senior Notes [Member] \| Senior Notes Due 2030, 4.625%
Debt Instruments [Line Items]
Debt Instrument, Interest Rate, Stated Percentage			4.625%
Long-term Debt			$ 840,000,000				0
Other Debt [Member]
Debt Instruments [Line Items]
Long-term Debt			49,000,000				41,000,000
Revolving Credit Facility [Member] \| Line of Credit [Member]
Debt Instruments [Line Items]
Long-term Debt			0				0
Line of Credit Facility, Remaining Borrowing Capacity			3,500,000,000
Line of Credit Facility, Maximum Borrowing Capacity					$ 3,500,000,000
Letter of Credit [Member] \| Line of Credit [Member]
Debt Instruments [Line Items]
Long-term Line of Credit			10,000,000
Line of Credit Facility, Maximum Borrowing Capacity			1,500,000,000
Cerro Verde \| Shareholder Loan [Member]
Debt Instruments [Line Items]
Long-term Debt			0				0
Cerro Verde \| Line of Credit [Member]
Debt Instruments [Line Items]
Long-term Debt			$ 523,000,000				826,000,000
Cerro Verde \| Line of Credit [Member] \| Line of Credit [Member]
Debt Instruments [Line Items]
Term of Debt Agreement		5 years
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%
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%
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%
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%
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%
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			$ 124,000,000				125,000,000
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			$ 117,000,000				117,000,000
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			$ 115,000,000				$ 115,000,000