Consolidated Balance Sheets - USD ($) $ in Thousands	Sep. 30, 2025	Dec. 31, 2024
Current Assets:
Cash and Cash Equivalents	$ 444,672	$ 408,240
Short-Term Investments	0	51,993
Accounts and Notes Receivable:
Trade Receivables, net	328,601	136,750
Other Receivables, net	46,279	25,900
Inventories	407,500	96,201
Other Current Assets	173,366	66,874
Total Current Assets	1,400,418	785,958
Total Property, Plant and Equipment—Net	4,390,382	1,921,699
Other Assets:
Funds for Asset Retirement Obligations	139,931	12,054
Salary Retirement	45,654	41,938
Other Noncurrent Assets, net	219,503	117,894
Total Other Assets	405,088	171,886
TOTAL ASSETS	6,195,888	2,879,543
Current Liabilities:
Accounts Payable	286,323	143,635
Current Portion of Long-Term Debt	83,796	112,865
Other Accrued Liabilities	399,644	262,184
Total Current Liabilities	769,763	518,684
Long-Term Debt:
Long-Term Debt	313,221	79,524
Finance Lease Obligations	21,291	15,270
Total Long-Term Debt	334,512	94,794
Deferred Credits and Other Liabilities:
Postretirement Benefits Other Than Pensions	208,947	176,251
Pneumoconiosis Benefits	250,293	145,489
Asset Retirement Obligations	492,044	212,178
Workers’ Compensation	74,273	36,051
Salary Retirement	20,619	20,073
Deferred Income Taxes	158,035	49,214
Other Noncurrent Liabilities	108,608	58,562
Total Deferred Credits and Other Liabilities	1,312,819	697,818
TOTAL LIABILITIES	2,417,094	1,311,296
Stockholders' Equity:
Common Stock, $0.01 Par Value; 125,000,000 Shares Authorized, 51,216,697 Shares Issued and Outstanding at September 30, 2025; 62,500,000 Shares Authorized, 29,407,830 Shares Issued and Outstanding at December 31, 2024	512	294
Capital in Excess of Par Value	2,991,513	540,412
Retained Earnings	919,639	1,162,114
Accumulated Other Comprehensive Loss	(132,870)	(134,573)
TOTAL STOCKHOLDERS' EQUITY	3,778,794	1,568,247
TOTAL LIABILITIES AND STOCKHOLDERS' EQUITY	$ 6,195,888	$ 2,879,543