Pneumoconiosis ("Black Lung") Obligations	12 Months Ended
Dec. 31, 2025
Self Insurance Reserve Disclosure [Abstract]
Pneumoconiosis ("Black Lung") Obligations	Note 10— Pneumoconiosis ("Black Lung") Obligations The Company is responsible for medical and disability benefits for black lung disease under the Federal Coal Mine Health and Safety Act of 1969, as amended. Beginning on April 1, 2016 through May 31, 2018, the Company was insured under a guaranteed cost insurance policy, through a third-party insurance carrier, for black lung claims raised by any employee subsequent to the acquisition of certain assets of Walter Energy. Beginning on June 1, 2018 through May 31, 2020 and June 1, 2020 to May 31, 2024, the Company had a deductible policy where the Company was responsible for the first $0.5 million and $1.0 million, respectively, for each black lung claim. Beginning on June 1, 2024 the Company has a deductible policy where the Company is responsible for the first $2.0 million of each black lung claim. In addition, in connection with the acquisition of certain assets of Walter Energy, the Company assumed all black lung liabilities of Walter Energy and its U.S. subsidiaries incurred prior to March 31, 2016, for which the Company is self-insured. Due to a limited operating history as a stand-alone company and as a result of being self-insured for these historical black lung claims, the Department of Labor ("DOL") required the Company to post $17.0 million in the form of Treasury bills or surety bonds as collateral, in addition to maintaining a black lung trust acquired in the Walter Energy acquisition. The Company received a letter from the Division of Coal Mine Workers' Compensation ("DCMWC") on February 21, 2020 under its new process for self-insurance renewals that would require it to increase the amount of collateral posted to $39.8 million, but the Company had appealed such increase. The Company received another letter from the DCMWC on December 8, 2021 requesting additional information to support its appeal of the collateral requested by the DOL. On February 9, 2022, the DCMWC held a conference call with representatives from the Company related to our appeal. On July 12, 2022, the Company received a decision on our appeal from the DCMWC lowering the amount of collateral required to be posted from $39.8 million to $28.0 million. The Company appealed this decision. On January 19, 2023, the DOL proposed revisions to regulations under the Black Lung Benefits Act governing authorization of self-insurers, which was then subsequently revised as part of the final rules published on December 12, 2024, which became effective on January 13, 2025 (the "2025 Final Regulation"). The 2025 Final Regulation required, among other requirements, all self-insured operators to post security of at least 100 percent of their projected black lung liabilities. On January 14, 2025, the Company received a letter from the DCMWC outlining the new procedures and application process for authorizing operators to self-insure under the new regulation. The letter outlined authorization form requirements and provided a 60-day period for the submission of the required documents. Subsequently, on February 20, 2025, the Company received another letter from the DCMWC stating that the 60-day deadline to provide information was no longer applicable and no information was required to be submitted at this time. DCWMC further stated that additional guidance would be provided in due course after consultation with the new DOL leadership. As of December 31, 2025 and December 31, 2024, the Company had $18.6 million of surety bonds, respectively, and $9.9 million and $9.5 million of collateral recognized as short term investments, respectively. There were also $0.9 million and $1.4 million of assets held in a black lung trust, which is offset against the long-term portion of the black lung obligations within the Consolidated Balance Sheets as of December 31, 2025 and December 31, 2024, respectively. The estimated total black lung liabilities (net of black lung trust assets) were $36.1 million as of December 31, 2025, of which $2.1 million is classified in other current liabilities and the remainder of $34.0 million is shown as a long-term liability in a separate line item in the Consolidated Balance Sheets. As of December 31, 2024, the estimated black lung liabilities (net of the black lung trust assets) were $36.7 million, of which $2.2 million is classified in other current liabilities and $34.5 million is classified as a long-term liability in a separate line item in the Consolidated Balance Sheets. Accretion of the black lung liabilities is included in cost of other revenues on the Consolidated Statements of Operations. The Company performs an annual evaluation of its black lung liabilities at each balance sheet date. The calculation uses assumptions regarding rates of successful claims, discount factors, benefit increases and mortality rates, among others. For the years ended December 31, 2025 and December 31, 2024, the change to the liability was primarily attributable to a decrease in open claims and the net impact of a change in discount rates, respectively. For the years ended December 31, 2025 and December 31, 2024, the annual evaluation resulted in income of $1.3 million or $0.02 per share and expense of $7.3 million or $0.14 per share, respectively, which is included in costs of other revenues in the Consolidated Statements of Operations.

Pneumoconiosis ("Black Lung") Obligations

12 Months Ended

Dec. 31, 2025

Self Insurance Reserve Disclosure [Abstract]

Pneumoconiosis ("Black Lung") Obligations

Note 10— Pneumoconiosis ("Black Lung") Obligations

The Company is responsible for medical and disability benefits for black lung disease under the Federal Coal Mine Health and Safety Act of 1969, as amended. Beginning on April 1, 2016 through May 31, 2018, the Company was insured under a guaranteed cost insurance policy, through a third-party insurance carrier, for black lung claims raised by any employee subsequent to the acquisition of certain assets of Walter Energy. Beginning on June 1, 2018 through May 31, 2020 and June 1, 2020 to May 31, 2024, the Company had a deductible policy where the Company was responsible for the first $0.5 million and $1.0 million, respectively, for each black lung claim. Beginning on June 1, 2024 the Company has a deductible policy where the Company is responsible for the first $2.0 million of each black lung claim.

In addition, in connection with the acquisition of certain assets of Walter Energy, the Company assumed all black lung liabilities of Walter Energy and its U.S. subsidiaries incurred prior to March 31, 2016, for which the Company is self-insured. Due to a limited operating history as a stand-alone company and as a result of being self-insured for these historical black lung claims, the Department of Labor ("DOL") required the Company to post $17.0 million in the form of Treasury bills or surety bonds as collateral, in addition to maintaining a black lung trust acquired in the Walter Energy acquisition. The Company received a letter from the Division of Coal Mine Workers' Compensation ("DCMWC") on February 21, 2020 under its new process for self-insurance renewals that would require it to increase the amount of collateral posted to $39.8 million, but the Company had appealed such increase. The Company received another letter from the DCMWC on December 8, 2021 requesting additional information to support its appeal of the collateral requested by the DOL. On February 9, 2022, the DCMWC held a conference call with representatives from the Company related to our appeal. On July 12, 2022, the Company received a decision on our appeal from the DCMWC lowering the amount of collateral required to be posted from $39.8 million to $28.0 million. The Company appealed this decision.

On January 19, 2023, the DOL proposed revisions to regulations under the Black Lung Benefits Act governing authorization of self-insurers, which was then subsequently revised as part of the final rules published on December 12, 2024, which became effective on January 13, 2025 (the "2025 Final Regulation"). The 2025 Final Regulation required, among other requirements, all self-insured operators to post security of at least 100 percent of their projected black lung liabilities. On January 14, 2025, the Company received a letter from the DCMWC outlining the new procedures and application process for authorizing operators to self-insure under the new regulation. The letter outlined authorization form requirements and provided a 60-day period for the submission of the required documents. Subsequently, on February 20, 2025, the Company received another letter from the DCMWC stating that the 60-day deadline to provide information was no longer applicable and no information was required to be submitted at this time. DCWMC further stated that additional guidance would be provided in due course after consultation with the new DOL leadership.

As of December 31, 2025 and December 31, 2024, the Company had $18.6 million of surety bonds, respectively, and $9.9 million and $9.5 million of collateral recognized as short term investments, respectively. There were also $0.9 million and $1.4 million of assets held in a black lung trust, which is offset against the long-term portion of the black lung obligations within the Consolidated Balance Sheets as of December 31, 2025 and December 31, 2024, respectively. The estimated total black lung liabilities (net of black lung trust assets) were $36.1 million as of December 31, 2025, of which $2.1 million is classified in other current liabilities and the remainder of $34.0 million is shown as a long-term liability in a separate line item in the Consolidated Balance Sheets. As of December 31, 2024, the estimated black lung liabilities (net of the black lung trust assets) were $36.7 million, of which $2.2 million is classified in other current liabilities and $34.5 million is classified as a

long-term liability in a separate line item in the Consolidated Balance Sheets. Accretion of the black lung liabilities is included in cost of other revenues on the Consolidated Statements of Operations. The Company performs an annual evaluation of its black lung liabilities at each balance sheet date. The calculation uses assumptions regarding rates of successful claims, discount factors, benefit increases and mortality rates, among others. For the years ended December 31, 2025 and December 31, 2024, the change to the liability was primarily attributable to a decrease in open claims and the net impact of a change in discount rates, respectively. For the years ended December 31, 2025 and December 31, 2024, the annual evaluation resulted in income of $1.3 million or $0.02 per share and expense of $7.3 million or $0.14 per share, respectively, which is included in costs of other revenues in the Consolidated Statements of Operations.