| Document and Entity Information | Aug. 20, 2021 |
| Cover [Abstract] | |
| Entity Registrant Name | INTERNATIONAL PAPER CO /NEW/ |
| Amendment Flag | false |
| Entity Central Index Key | 0000051434 |
| Document Type | 8-K |
| Document Period End Date | Aug. 20, 2021 |
| Entity Incorporation State Country Code | NY |
| Entity File Number | 1-3157 |
| Entity Tax Identification Number | 13-0872805 |
| Entity Address, Address Line One | 6400 Poplar Avenue |
| Entity Address, City or Town | Memphis |
| Entity Address, State or Province | TN |
| Entity Address, Postal Zip Code | 38197 |
| City Area Code | (901) |
| Local Phone Number | 419-7000 |
| Written Communications | false |
| Soliciting Material | false |
| Pre Commencement Tender Offer | false |
| Pre Commencement Issuer Tender Offer | false |
| Security 12b Title | Common Stock, $1 per share par value |
| Trading Symbol | IP |
| Security Exchange Name | NYSE |
| Entity Emerging Growth Company | false |
