| Cover Page | Oct. 22, 2020 |
| Cover [Abstract] | |
| Document Type | 8-K |
| Document Period End Date | Oct. 22, 2020 |
| Entity Registrant Name | Freeport-McMoRan Inc. |
| Entity Incorporation, State or 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 |
| Title of 12(b) Security | Common Stock, par value $0.10 per share |
| Trading Symbol | FCX |
| Security Exchange Name | NYSE |
| Entity Emerging Growth Company | false |
| Entity Central Index Key | 0000831259 |
| Amendment Flag | false |
