v3.25.2
Segment Information (Disaggregation of Revenue) (Details) - USD ($)
$ in Thousands
 3 Months Ended 6 Months Ended
Jun. 30, 2025
Jun. 30, 2024
Jun. 30, 2025
Jun. 30, 2024
Disaggregation of Revenue [Line Items]        
Total coal revenues $ 459,337 $ 664,379 $ 900,788 $ 1,297,372
Other revenues 8,542 9,449 16,339 44,605
Total 467,879 673,828 917,127 1,341,977
Metallurgical Coal [Member]        
Disaggregation of Revenue [Line Items]        
Total coal revenues 427,328 639,361 848,831 1,241,195
Thermal Coal [Member]        
Disaggregation of Revenue [Line Items]        
Total coal revenues 32,009 25,018 51,957 56,177
Australia Segment [Member] | Operating Segments [Member]        
Disaggregation of Revenue [Line Items]        
Total coal revenues 251,537 449,497 517,561 877,094
Other revenues 8,308 8,994 15,561 17,502
Total 259,845 458,491 533,122 894,596
Australia Segment [Member] | Metallurgical Coal [Member] | Operating Segments [Member]        
Disaggregation of Revenue [Line Items]        
Total coal revenues 230,624 429,506 480,690 837,809
Australia Segment [Member] | Thermal Coal [Member] | Operating Segments [Member]        
Disaggregation of Revenue [Line Items]        
Total coal revenues 20,913 19,991 36,871 39,285
United States Segment [Member] | Operating Segments [Member]        
Disaggregation of Revenue [Line Items]        
Total coal revenues 207,800 214,882 383,227 420,278
Other revenues 234 455 778 27,103
Total 208,034 215,337 384,005 447,381
United States Segment [Member] | Metallurgical Coal [Member] | Operating Segments [Member]        
Disaggregation of Revenue [Line Items]        
Total coal revenues 196,704 209,855 368,141 403,386
United States Segment [Member] | Thermal Coal [Member] | Operating Segments [Member]        
Disaggregation of Revenue [Line Items]        
Total coal revenues $ 11,096 $ 5,027 $ 15,086 16,892
United States Segment [Member] | Total Coal Revenue [Member]        
Disaggregation of Revenue [Line Items]        
Termination fee revenue       $ 25,000