Consolidated Balance Sheets - USD ($) $ in Thousands	Jun. 30, 2024	Dec. 31, 2023
Current Assets:
Cash and Cash Equivalents	$ 216,115	$ 199,371
Short-Term Investments	83,344	81,932
Accounts and Notes Receivable
Trade Receivables, net	143,928	147,612
Other Receivables, net	15,653	12,765
Inventories	97,507	88,154
Other Current Assets	64,665	71,172
Total Current Assets	621,212	601,006
Property, Plant and Equipment:
Property, Plant and Equipment	5,655,655	5,552,404
Less - Accumulated Depreciation, Depletion and Amortization	3,744,633	3,649,281
Total Property, Plant and Equipment—Net	1,911,022	1,903,123
Other Assets:
Right of Use Asset - Operating Leases	14,119	14,658
Salary Retirement	50,371	47,246
Other Noncurrent Assets, net	113,730	108,970
Total Other Assets	178,220	170,874
TOTAL ASSETS	2,710,454	2,675,003
Current Liabilities:
Accounts Payable	136,848	137,243
Current Portion of Long-Term Debt	6,012	11,106
Operating Lease Liability, Current Portion	4,167	4,769
Other Accrued Liabilities	253,061	290,606
Total Current Liabilities	400,088	443,724
Long-Term Debt:
Long-Term Debt	182,009	181,885
Finance Lease Obligations	2,922	4,182
Total Long-Term Debt	184,931	186,067
Deferred Credits and Other Liabilities:
Postretirement Benefits Other Than Pensions	205,060	207,908
Pneumoconiosis Benefits	152,324	154,943
Asset Retirement Obligations	212,866	212,621
Workers’ Compensation	38,413	39,144
Salary Retirement	20,720	20,808
Operating Lease Liability	10,486	10,385
Deferred Income Taxes	36,399	36,219
Other Noncurrent Liabilities	10,764	19,742
Total Deferred Credits and Other Liabilities	687,032	701,770
TOTAL LIABILITIES	1,272,051	1,331,561
Stockholders' Equity:
Common Stock, $0.01 Par Value; 62,500,000 Shares Authorized, 29,392,987 Shares Issued and Outstanding at June 30, 2024; 29,910,439 Shares Issued and Outstanding at December 31, 2023	294	299
Capital in Excess of Par Value	535,965	547,861
Retained Earnings	1,050,577	944,342
Accumulated Other Comprehensive Loss	(148,433)	(149,060)
TOTAL EQUITY	1,438,403	1,343,442
TOTAL LIABILITIES AND EQUITY	$ 2,710,454	$ 2,675,003