New Accounting Standard	9 Months Ended
Sep. 30, 2020
New Accounting Pronouncements and Changes in Accounting Principles [Abstract]
New Accounting Standards	NEW ACCOUNTING STANDARDFinancial Instruments. In June 2016, the Financial Accounting Standards Board issued an Accounting Standards Update (ASU) that requires entities to estimate all expected credit losses for most financial assets held at the reporting date based on an expected loss model, which requires consideration of historical experience, current conditions, and reasonable and supportable forecasts. FCX adopted this ASU effective January 1, 2020, and the adoption of this ASU did not have a material impact on its consolidated financial statements.

The entire disclosure of changes in accounting principles, including adoption of new accounting pronouncements, that describes the new methods, amount and effects on financial statement line items.

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 250
-URI http://asc.fasb.org/topic&trid=2122394

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