| Cover | Aug. 06, 2021 |
| Cover [Abstract] | |
| Document Type | 8-K |
| Document Period End Date | Aug. 6, 2021 |
| Entity Registrant Name | NATURAL RESOURCE PARTNERS LP |
| Entity Incorporation, State or Country Code | DE |
| Entity File Number | 001-31465 |
| Entity Tax Identification Number | 35-2164875 |
| Entity Address, Address Line One | 1201 Louisiana St., Suite 3400 |
| Entity Address, City or Town | Houston, |
| Entity Address, State or Province | TX |
| Entity Address, Postal Zip Code | 77002 |
| City Area Code | (713) |
| Local Phone Number | 751-7507 |
| Title of 12(b) Security | Common Units representing limited partner interests |
| Trading Symbol | NRP |
| Security Exchange Name | NYSE |
| Written Communications | false |
| Soliciting Material | false |
| Pre-commencement Tender Offer | false |
| Pre-commencement Issuer Tender Offer | false |
| Entity Emerging Growth Company | false |
| Amendment Flag | false |
| Entity Central Index Key | 0001171486 |
