Consolidated Balance Sheets (Current Period Unaudited) - USD ($) $ in Thousands	Mar. 31, 2021	Dec. 31, 2020
Current Assets:
Cash and Cash Equivalents	$ 91,174	$ 50,850
Restricted Cash	303	0
Accounts and Notes Receivable
Trade Receivables, net	124,629	118,289
Other Receivables, net	41,602	42,157
Inventories	55,209	56,200
Prepaid Expenses and Other Assets	23,825	25,445
Total Current Assets	336,742	292,941
Property, Plant and Equipment:
Property, Plant and Equipment	5,131,739	5,143,696
Less - Accumulated Depreciation, Depletion and Amortization	3,117,651	3,094,634
Total Property, Plant and Equipment—Net	2,014,088	2,049,062
Other Assets:
Deferred Income Taxes	62,261	68,821
Right of Use Asset - Operating Leases	48,337	53,436
Other, net	59,132	59,106
Total Other Assets	169,730	181,363
TOTAL ASSETS	2,520,560	2,523,366
Current Liabilities:
Accounts Payable	75,382	71,229
Current Portion of Long-Term Debt	50,057	53,846
Other Accrued Liabilities	245,755	243,395
Total Current Liabilities	371,194	368,470
Long-Term Debt:
Long-Term Debt	550,444	566,858
Finance Lease Obligations	34,877	36,203
Total Long-Term Debt	585,321	603,061
Deferred Credits and Other Liabilities:
Postretirement Benefits Other Than Pensions	383,457	387,637
Pneumoconiosis Benefits	228,687	229,720
Asset Retirement Obligations	227,922	228,182
Workers’ Compensation	63,414	64,390
Salary Retirement	28,527	35,359
Operating Lease Liability	32,434	35,655
Other	16,539	17,373
Total Deferred Credits and Other Liabilities	980,980	998,316
TOTAL LIABILITIES	1,937,495	1,969,847
Stockholders' Equity:
Common Stock, $0.01 Par Value; 62,500,000 Shares Authorized, 34,371,205 Shares Issued and Outstanding at March 31, 2021; 34,031,374 Shares Issued and Outstanding at December 31, 2020	344	340
Capital in Excess of Par Value	642,054	642,887
Retained Earnings	273,254	246,850
Accumulated Other Comprehensive Loss	(332,587)	(336,558)
TOTAL EQUITY	583,065	553,519
TOTAL LIABILITIES AND EQUITY	$ 2,520,560	$ 2,523,366