| Document and Entity Information | Mar. 04, 2020 |
| Cover [Abstract] | |
| Entity Registrant Name | FREEPORT-MCMORAN INC |
| Amendment Flag | false |
| Entity Central Index Key | 0000831259 |
| Document Type | 8-K |
| Document Period End Date | Mar. 4, 2020 |
| Entity Incorporation State Country Code | DE |
| Entity File Number | 001-11307-01 |
| Entity Tax Identification Number | 74-2480931 |
| Entity Address, Address Line One | 333 North Central Avenue |
| Entity Address, City or Town | Phoenix |
| Entity Address, State or Province | AZ |
| Entity Address, Postal Zip Code | 85004 |
| City Area Code | (602) |
| Local Phone Number | 366-8100 |
| Written Communications | false |
| Soliciting Material | false |
| Pre Commencement Tender Offer | false |
| Pre Commencement Issuer Tender Offer | false |
| Security 12b Title | Common Stock, par value $0.10 per share |
| Trading Symbol | FCX |
| Security Exchange Name | NYSE |
| Entity Emerging Growth Company | false |
