v3.26.1
Note 11 - Major Customers - Concentration Risk (Details) - USD ($)
$ in Thousands
3 Months Ended
Mar. 31, 2026
Mar. 31, 2025
Alpha Metallurgical Resources [Member]    
Net sales [1] $ 13,701 $ 13,176
Alpha Metallurgical Resources [Member] | Revenue Benchmark [Member] | Customer Concentration Risk [Member]    
Revenue, percent [1] 29.00% 24.00%
Foresight Energy Resources [Member]    
Net sales [1] $ 13,497 $ 16,460
Foresight Energy Resources [Member] | Revenue Benchmark [Member] | Customer Concentration Risk [Member]    
Revenue, percent [1] 29.00% 30.00%
Alabama Kanu Holdings [Member]    
Net sales [1] $ 4,730 $ 3,258
Alabama Kanu Holdings [Member] | Revenue Benchmark [Member] | Customer Concentration Risk [Member]    
Revenue, percent [1] 10.00% 6.00%
[1] Revenues from Alpha Metallurgical Resources, Inc., Foresight, and Alabama Kanu Holdings, LLC are generated in the United States of America and are included within the Partnership's Mineral Rights segment.