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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%

X

- Definition

The percentage of unit holders approved by written consent for the simplification agreement on record date.

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The number of common units issued in an exchange transaction.

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- Definition

The number of gross royalty acres acquired.

+ References

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The number of net royalty acres acquired.

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Number of royalty acres under control of the entity.

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The number of limited partner units issued to SGP in Simplification Transactions.

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Percentage investment held by the managing member or general partner of the limited liability company (LLC) or limited partnership (LP).

+ References

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-Publisher FASB
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-SubTopic 10
-Section 50
-Paragraph 3
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Percentage investment held by members or limited partners of limited liability company (LLC) or limited partnership (LP).

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The number of units converted into shares of each class of partners' capital account. Units represent shares of ownership of the general, limited, and preferred partners.

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