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Principles of Consolidation and Nature of Operations (Narrative) (Details) $ in Thousands | 1 Months Ended | 12 Months Ended
--- | --- | ---
May 31, 2024 USD ($) | Dec. 31, 2024 USD ($) a segment | Dec. 31, 2023 USD ($) a
Long-term Purchase Commitment [Line Items] |  |  |
Number of operating segments | segment |  | 3 |
Long-lived asset impairment charge |  | $ 0 | $ 65,887
Business interruption insurance recoveries |  | 13,612 | 0
Acquisitions of mineral and royalty interests |  | $ 713 | $ 36,714
Gross acres | a |  | 13,700 | 43,400
Net royalty acres | a |  | 600 | 2,500
Gross acres of mineral and royalty interest | a |  | 198,400 |
Net royalty acres of mineral and royalty interest | a |  | 63,900 |
Assets held for sale |  | $ 14,159 | $ 6,466
Defined Benefit Plan, Net Periodic Benefit Cost (Credit) Excluding Service Cost, Statement of Income or Comprehensive Income [Extensible Enumeration] |  |  | Other Nonoperating Income (Expense)
HLCP |  |  |
Long-term Purchase Commitment [Line Items] |  |  |
Post-closing purchase price adjustment |  |  | $ 3,600
Pension Plan |  |  |
Long-term Purchase Commitment [Line Items] |  |  |
Settlements |  | 0 | 1,815
Minerals Management |  |  |
Long-term Purchase Commitment [Line Items] |  |  |
Sale of land | $ 7,000 |  |
Gain in the minerals management segment | $ 4,500 |  |
Eiger, LLC |  |  |
Long-term Purchase Commitment [Line Items] |  |  |
Equity method investment in Eiger, LLC |  | 19,147 | $ 2,800
Income from equity method investee |  | 600 |
Eiger, LLC | Minerals Management |  |  |
Long-term Purchase Commitment [Line Items] |  |  |
Equity method investment in Eiger, LLC |  | 19,100 |
Eiger, LLC | Fourth Quarter 2024 Investment in Oil and Natural Gas Interests |  |  |
Long-term Purchase Commitment [Line Items] |  |  |
Equity method investment in Eiger, LLC |  | $ 15,700 |

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