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ORGANIZATION AND PRESENTATION (Details) |  |  |  |  | 12 Months Ended
--- | --- | --- | --- | --- | ---
Aug. 02, 2019 a | Feb. 08, 2019 a | Jan. 03, 2019 a | May 31, 2018 shares | Dec. 31, 2020
AllDale I and II |  |  |  |  |
Ownership interests |  |  |  |  |
Royalty acres, net | a |  |  | 43,000 |  |
Wing |  |  |  |  |
Ownership interests |  |  |  |  |
Royalty acres controlled | a |  | 55,700 |  |  |
Royalty acres, net | a | 9,000 |  |  |  |
Royalty acres, gross | a | 400,000 |  |  |  |
SGP | AHGP |  |  |  |  |
Ownership interests |  |  |  |  |
Ownership percentage by limited partners |  |  |  |  | 34.48%
Simplification Transactions | SGP |  |  |  |  |
Ownership interests |  |  |  |  |
Common units issued in exchange | shares |  |  |  | 29,188,997 |
Issuance of units to Owners of SGP in Simplification Transactions (in units) | shares |  |  |  | 1,322,388 |
Simplification Transactions | AHGP |  |  |  |  |
Ownership interests |  |  |  |  |
Units issued in exchange (in units) | shares |  |  |  | 1.4782 |
Simplification Transactions | Intermediate Partnership |  |  |  |  |
Ownership interests |  |  |  |  |
Ownership percentage by general partners |  |  |  | 1.0001% |
Simplification Transactions | Alliance Coal |  |  |  |  |
Ownership interests |  |  |  |  |
Ownership percentage by general partners |  |  |  | 0.001% |
Simplification Transactions | AHGP |  |  |  |  |
Ownership interests |  |  |  |  |
Approved written consent percent |  |  |  | 68.00% |
Units issued in exchange (in units) | shares |  |  |  | 1.4782 |
Simplification Transactions | AHGP | Intermediate Partnership |  |  |  |  |
Ownership interests |  |  |  |  |
Ownership percentage by general partners |  |  |  | 1.0001% |
Simplification Transactions | AHGP | Alliance Coal |  |  |  |  |
Ownership interests |  |  |  |  |
Ownership percentage by general partners |  |  |  | 0.001% |
Simplification Transactions | SGP | Intermediate Partnership |  |  |  |  |
Ownership interests |  |  |  |  |
Ownership percentage by general partners |  |  |  | 1.0001% |
Simplification Transactions | SGP | Alliance Coal |  |  |  |  |
Ownership interests |  |  |  |  |
Ownership percentage by general partners |  |  |  | 0.001% |

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