v3.26.1
Note 11 - Major Customers - Concentration Risk (Details) - USD ($)
$ in Thousands
3 Months Ended 6 Months Ended
Jun. 30, 2026
Jun. 30, 2025
Jun. 30, 2026
Jun. 30, 2025
Foresight Energy Resources [Member]        
Net sales [1] $ 13,830 $ 9,796 $ 27,327 $ 26,256
Foresight Energy Resources [Member] | Revenue Benchmark [Member] | Customer Concentration Risk [Member]        
Revenue, percent [1] 26.00% 21.00% 27.00% 26.00%
Alpha Metallurgical Resources [Member]        
Net sales [1] $ 13,517 $ 13,184 $ 27,218 $ 26,360
Alpha Metallurgical Resources [Member] | Revenue Benchmark [Member] | Customer Concentration Risk [Member]        
Revenue, percent [1] 26.00% 28.00% 27.00% 26.00%
Alabama Kanu Holdings [Member]        
Net sales [1] $ 5,856 $ 5,284 $ 10,586 $ 8,543
Alabama Kanu Holdings [Member] | Revenue Benchmark [Member] | Customer Concentration Risk [Member]        
Revenue, percent [1] 11.00% 11.00% 11.00% 8.00%
[1] Revenues from Foresight, Alpha Metallurgical Resources, Inc., and Alabama Kanu Holdings, LLC are generated in the United States of America and are included within the Partnership's Mineral Rights segment.