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Significant Customers	12 Months Ended
Significant Customers	Dec. 31, 2017
Risks and Uncertainties [Abstract]
Significant Customers	SIGNIFICANT CUSTOMERS The Partnership leases mineral interests to exploration and production companies and participates in non-operated working interests when economic conditions are favorable. XTO Energy Inc., a subsidiary of Exxon Mobil Corporation ("Exxon"), represented approximately 21% of total revenue for the year ended December 31, 2017. Exxon represented approximately 11% of total revenue for the year ended December 31, 2016. No customer represented 10% or more of total revenue for the year ended December 31, 2015. If the Partnership lost a significant customer, such loss could impact revenue derived from its mineral and royalty interests and working interests. The loss of any single customer is mitigated by the Partnership’s diversified customer base.