Unaudited Condensed Consolidated Balance Sheets - USD ($) $ in Thousands	Sep. 30, 2020	Dec. 31, 2019
ASSETS
Cash and cash equivalents	$ 97,567	$ 122,892
Trade accounts receivable, net	16,507	15,444
Accounts receivable from affiliates	3,722	6,411
Inventories	42,433	40,465
Refundable federal income taxes	25,379	8,928
Other current assets	12,996	6,528
Total current assets	198,604	200,668
Property, plant and equipment, net	156,598	138,061
Intangibles, net	35,599	37,902
Investments in unconsolidated subsidiaries	25,545	24,611
Operating lease right-of-use assets	10,448	11,398
Other non-current assets	39,108	32,133
Total assets	465,902	444,773
LIABILITIES AND EQUITY
Accounts payable	13,603	9,374
Accounts payable to affiliates	686	577
Revolving credit agreements	0	7,000
Current maturities of long-term debt	960	795
Asset retirement obligations	2,285	2,285
Accrued payroll	10,565	19,583
Deferred compensation	0	13,465
Deferred revenue	1,693	1,908
Other current liabilities	6,786	6,979
Total current liabilities	36,578	61,966
Long-term debt	22,182	17,148
Operating lease liabilities	11,494	12,448
Asset retirement obligations	40,811	34,574
Pension and other postretirement obligations	7,430	8,807
Deferred income taxes	28,513	12,338
Other long-term liabilities	12,405	8,100
Total liabilities	159,413	155,381
Common stock:
Capital in excess of par value	9,381	8,911
Retained earnings	301,045	284,852
Accumulated other comprehensive loss	(10,982)	(11,337)
Total stockholders' equity	306,489	289,392
Total liabilities and equity	465,902	444,773
Class A Common Stock
Common stock:
Common stock	5,477	5,397
Class B Common Stock
Common stock:
Common stock	$ 1,568	$ 1,569