Significant Accounting Policies (Policies)	6 Months Ended
Jun. 30, 2023
Summary of Significant Accounting Policies.
Basis of Presentation	Basis of Presentation—These interim financial statements are unaudited and have been prepared pursuant to the rules and regulations of the SEC regarding interim financial reporting. Certain disclosures have been condensed or omitted from these financial statements. Accordingly, they do not include all the information and notes required by accounting principles generally accepted in the United States of America (“GAAP”) for complete consolidated financial statements and should be read in conjunction with the audited consolidated financial statements and notes thereto included in our Annual Report on Form 10-K for the year ended December 31, 2022. In the opinion of the Company, the accompanying unaudited condensed consolidated financial statements include all adjustments, consisting of only normal recurring adjustments, necessary for a fair statement of the Company’s financial position as of June 30, 2023, as well as the results of operations and cash flows for all periods presented. In preparing the accompanying financial statements, management has made certain estimates and assumptions that affect reported amounts in the condensed consolidated financial statements and disclosures of contingencies. Actual results may differ from those estimates. The results for interim periods are not necessarily indicative of annual results. Intercompany balances and transactions between consolidated entities have been eliminated. There were no material changes to the Company’s significant accounting policies during the first six months of 2023.
Concentrations	Concentrations—During the three months ended June 30, 2023, sales to our top two customers accounted for approximately 35% of our total revenue. During the six months ended June 30, 2023, sales to our top four customers accounted for approximately 49% of our total revenue. During the three months ended June 30, 2022, sales to our top four customers accounted for approximately 65% of total revenue. During the six months ended June 30, 2022, sales to our top three customers accounted for approximately 53% of total revenue. The number of customers comprising the concentrations above is based on a threshold of 10% or more of total revenues. Three customers with individual accounts receivable balances equal to 10% or more of total accounts receivable made up approximately 61% of the Company’s accounts receivable balance at June 30, 2023. Segments—CORE represents a separate operating segment and has economic and geographic differences compared to the Company’s metallurgical operations in the Appalachian basin; however, CORE does not meet the significance tests for separate disclosure as a reportable segment at this time. In addition, reconciling items of the metallurgical coal segment to the Company’s consolidated results are not yet material. CORE revenues disclosed in Note 6 are primarily intracompany revenues eliminated upon consolidation and are not included in the disaggregated revenue table above.

Significant Accounting Policies (Policies)

6 Months Ended

Jun. 30, 2023

Summary of Significant Accounting Policies.

Basis of Presentation—These interim financial statements are unaudited and have been prepared pursuant to the rules and regulations of the SEC regarding interim financial reporting. Certain disclosures have been condensed or omitted from these financial statements. Accordingly, they do not include all the information and notes required by accounting principles generally accepted in the United States of America (“GAAP”) for complete consolidated financial statements and should be read in conjunction with the audited consolidated financial statements and notes thereto included in our Annual Report on Form 10-K for the year ended December 31, 2022.

In the opinion of the Company, the accompanying unaudited condensed consolidated financial statements include all adjustments, consisting of only normal recurring adjustments, necessary for a fair statement of the Company’s financial position as of June 30, 2023, as well as the results of operations and cash flows for all periods presented. In preparing the accompanying financial statements, management has made certain estimates and assumptions that affect reported amounts in the condensed consolidated financial statements and disclosures of contingencies. Actual results may differ from those estimates. The results for interim periods are not necessarily indicative of annual results. Intercompany balances and transactions between consolidated entities have been eliminated.

There were no material changes to the Company’s significant accounting policies during the first six months of 2023.

Concentrations

Concentrations—During the three months ended June 30, 2023, sales to our top two customers accounted for approximately 35% of our total revenue. During the six months ended June 30, 2023, sales to our top four customers accounted for approximately 49% of our total revenue. During the three months ended June 30, 2022, sales to our top four customers accounted for approximately 65% of total revenue. During the six months ended June 30, 2022, sales to our top three customers accounted for approximately 53% of total revenue. The number of customers comprising the concentrations above is based on a threshold of 10% or more of total revenues. Three customers with individual accounts receivable balances equal to 10% or more of total accounts receivable made up approximately 61% of the Company’s accounts receivable balance at June 30, 2023.

Segments—CORE represents a separate operating segment and has economic and geographic differences compared to the Company’s metallurgical operations in the Appalachian basin; however, CORE does not meet the significance tests for separate disclosure as a reportable segment at this time. In addition, reconciling items of the metallurgical coal segment to the Company’s consolidated results are not yet material. CORE revenues disclosed in Note 6 are primarily intracompany revenues eliminated upon consolidation and are not included in the disaggregated revenue table above.