v3.25.3
Segment Reporting - Schedule of Reportable Segment Information (Details) - Segment [Member] - USD ($)
$ in Thousands
 3 Months Ended 9 Months Ended
Sep. 30, 2025
Sep. 30, 2024
Sep. 30, 2025
Sep. 30, 2024
Segment Reporting Information [Line Items]        
Revenue $ 120,996 $ 167,411 $ 408,611 $ 495,403
Significant segment expenses:        
Cost of sales (exclusive of transportation costs) (85,476) (104,817) [1] (290,289) [2] (313,297) [1]
Transportation costs (16,366) (28,551) (56,037) (80,299)
Selling, general, and administrative [3] (8,179) (8,570) (26,841) (23,432)
Other segment items [4] 1,208 132 3,516 3,870
Segment Adjusted EBITDA 12,184 25,605 38,960 82,245
Corporate expenses [5] (3,233) (1,744) (10,072) (4,862)
Stock-based compensation (4,731) (3,970) (12,844) (13,255)
Asset retirement obligations accretion (402) (354) (1,206) (1,063)
Depreciation, depletion, and amortization (17,091) (17,811) (51,671) (48,909)
Other expenses (1,083) (208) (2,228) (796)
Interest expense, net (2,250) (1,696) (7,298) (4,509)
Income tax benefit (expense) 3,299 (61) 9,618 (1,517)
Net (loss) income (13,308) (239) (36,741) 7,334
Segment capital expenditures 13,385 15,751 49,261 56,778
Other capital expenditures [6] 11 50 15 216
Total capital expenditures (including accrued capital expenditures and capitalized interest) 13,396 15,801 49,276 56,994
Metallurgical Coal [Member]        
Segment Reporting Information [Line Items]        
Revenue 120,996 167,411 408,611 495,403
Significant segment expenses:        
Cost of sales (exclusive of transportation costs) (85,476) (104,817) [1] (290,289) [2] (313,297) [1]
Transportation costs (16,366) (28,551) (56,037) (80,299)
Selling, general, and administrative [3] (4,420) (7,207) (14,439) (19,815)
Other segment items [4] 1,208 132 3,516 3,870
Segment Adjusted EBITDA 15,943 26,968 51,362 85,862
Segment capital expenditures 11,510 15,751 46,841 56,757
REE & Critical Minerals [Member]        
Segment Reporting Information [Line Items]        
Revenue
Significant segment expenses:        
Cost of sales (exclusive of transportation costs) [1] [2] [1]
Transportation costs
Selling, general, and administrative [3] (3,759) (1,363) (12,402) (3,618)
Other segment items [4]
Segment Adjusted EBITDA (3,759) (1,363) (12,402) (3,618)
Segment capital expenditures $ 1,875 $ 2,420 $ 21
[1] The difference between this significant segment expense and “Cost of sales” within the Company’s unaudited Condensed Consolidated Statements of Operations relates to transportation costs, which are presented separately within the table above, and alternative mineral development costs, which are included in “Selling, general, and administrative” in the Rare Earths and Critical Minerals segment in the table above. The presentation of these amounts conform to the current year presentation.
[2] Alternative mineral development costs through June 30, 2025 of approximately $3.8 million have been reclassed from “Cost of sales” within the Company’s unaudited Condensed Consolidated Statements of Operations to “Selling, general, and administrative” in the Rare Earths and Critical Minerals segment. In addition, transportation costs are included in “Cost of sales” within the Company’s unaudited Condensed Consolidated Statements of Operations and are presented separately within the table above. The presentation of these amounts conform to the current period presentation.
[3] The primary differences between this significant segment expense and “Selling, general and administrative” within the Company’s unaudited Condensed Consolidated Statements of Operations relates to stock-based compensation and unallocated corporate costs, which are included in “Corporate expenses” and “Stock-based compensation” in the table above.
[4] “Other segment items” consists of items within “Other income (expense), net” on the Company’s unaudited Condensed Consolidated Statements of Operations, idle costs and other non-recurring costs that are not related to the segments’ underlying business performance.
[5] “Corporate expenses” represent costs incurred at the corporate offices that are not specifically attributable to the reportable segments.
[6] Includes amounts not allocated to the reportable segments, primarily related to corporate capital expenditures.