Note 1 - Basis of Presentation	9 Months Ended
Sep. 30, 2023
Notes to Financial Statements
Basis of Presentation and Significant Accounting Policies [Text Block]	1. Basis of Presentation Nature of Business Natural Resource Partners L.P. (the "Partnership") engages principally in the business of owning, managing and leasing a diversified portfolio of mineral properties in the United States, including interests in coal and other natural resources and owns a non-controlling 49% interest in Sisecam Wyoming LLC ("Sisecam Wyoming"), a trona ore mining and soda ash production business. The Partnership is organized into two operating segments further described in Note 6. Segment Information. The Partnership’s operations are conducted through, and its operating assets are owned by, its subsidiaries. The Partnership owns its subsidiaries through one wholly owned operating company, NRP (Operating) LLC ("Opco"). As used in these Notes to Consolidated Financial Statements, the terms "NRP," "we," "us" and "our" refer to Natural Resource Partners L.P. and its subsidiaries, unless otherwise stated or indicated by context. Principles of Consolidation and Reporting The accompanying unaudited Consolidated Financial Statements of the Partnership have been prepared in accordance with generally accepted accounting principles in the United States of America ("GAAP") for interim financial information and with Rule 10-01 of Regulation S-X. Accordingly, they do not include all of the information and footnotes required by GAAP for complete financial statements. These financial statements should be read in conjunction with the financial statements for the year ended December 31, 2022 and notes thereto included in the Partnership's Annual Report on Form 10-K, which was filed with the SEC on March 3, 2023. Reclassifications have been made to prior year amounts in the Consolidated Financial Statements to conform with current year presentation. These reclassifications had no impact on previously reported total assets, total liabilities, partners' capital, net income, or cash flows from operating, investing or financing activities. Recently Adopted Accounting Standard On January 1, 2023, NRP adopted Accounting Standards Update ("ASU") 2020-06, Debt – Debt with Conversion and Other Options (Subtopic 470-20) and Derivatives and Hedging – Contracts in Entity’s Own Equity (Subtopic 815-40) (“ASU 2020-06)”. The ASU includes targeted improvements to earnings per share, which the Partnership adopted on a modified retrospective basis. The adoption of this ASU did not have a material impact on the Partnership’s Consolidated Financial Statements. See Note 5. Net Income Per Common Unit for the calculations of our basic and diluted net income per common unit. See Note 3. Class A Convertible Preferred Units and Warrants for disclosures related to our convertible preferred units and warrants.

Note 1 - Basis of Presentation

9 Months Ended

Sep. 30, 2023

Basis of Presentation and Significant Accounting Policies [Text Block]

1. Basis of Presentation

Nature of Business

Natural Resource Partners L.P. (the "Partnership") engages principally in the business of owning, managing and leasing a diversified portfolio of mineral properties in the United States, including interests in coal and other natural resources and owns a non-controlling 49% interest in Sisecam Wyoming LLC ("Sisecam Wyoming"), a trona ore mining and soda ash production business. The Partnership is organized into two operating segments further described in Note 6. Segment Information. The Partnership’s operations are conducted through, and its operating assets are owned by, its subsidiaries. The Partnership owns its subsidiaries through one wholly owned operating company, NRP (Operating) LLC ("Opco"). As used in these Notes to Consolidated Financial Statements, the terms "NRP," "we," "us" and "our" refer to Natural Resource Partners L.P. and its subsidiaries, unless otherwise stated or indicated by context.

Principles of Consolidation and Reporting

The accompanying unaudited Consolidated Financial Statements of the Partnership have been prepared in accordance with generally accepted accounting principles in the United States of America ("GAAP") for interim financial information and with Rule 10-01 of Regulation S-X. Accordingly, they do not include all of the information and footnotes required by GAAP for complete financial statements. These financial statements should be read in conjunction with the financial statements for the year ended December 31, 2022 and notes thereto included in the Partnership's Annual Report on Form 10-K, which was filed with the SEC on March 3, 2023. Reclassifications have been made to prior year amounts in the Consolidated Financial Statements to conform with current year presentation. These reclassifications had no impact on previously reported total assets, total liabilities, partners' capital, net income, or cash flows from operating, investing or financing activities.

Recently Adopted Accounting Standard

On January 1, 2023, NRP adopted Accounting Standards Update ("ASU") 2020-06, Debt – Debt with Conversion and Other Options (Subtopic 470-20) and Derivatives and Hedging – Contracts in Entity’s Own Equity (Subtopic 815-40) (“ASU 2020-06)”. The ASU includes targeted improvements to earnings per share, which the Partnership adopted on a modified retrospective basis. The adoption of this ASU did not have a material impact on the Partnership’s Consolidated Financial Statements. See Note 5. Net Income Per Common Unit for the calculations of our basic and diluted net income per common unit. See Note 3. Class A Convertible Preferred Units and Warrants for disclosures related to our convertible preferred units and warrants.