CONSOLIDATED STATEMENTS OF CASH FLOWS - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2021	Dec. 31, 2020
Operating Activities
Net income	$ 48,125	$ 14,793
Adjustments to reconcile net income to net cash provided by operating activities:
Depreciation, depletion and amortization	23,085	18,114
Amortization of deferred financing fees	326	334
Deferred income taxes	(3,553)	7,517
Stock-based compensation	5,561	3,078
Gain on sale of assets	(60)	(269)
Inventory impairment charge	0	1,973
Other asset impairment charges	0	8,359
Other	1,647	(3,786)
Working capital changes:
Affiliates receivable/payable	495	20
Accounts receivable	(13,685)	42
Inventories	(6,534)	(9,361)
Other current assets	3,320	(2,582)
Accounts payable	7,445	(10,622)
Income taxes receivable/payable	2,699	(10,790)
Other current liabilities	6,004	(19,306)
Net cash provided by (used for) operating activities	74,875	(2,486)
Investing Activities
Expenditures for property, plant and equipment	(39,230)	(30,187)
Acquisition of mineral interests	(5,331)	(14,181)
Proceeds from the sale of assets	633	571
Purchase of equity securities	0	(2,000)
Other	(219)	(187)
Net cash used for investing activities	(44,147)	(45,984)
Financing Activities
Net (reductions) additions to revolving credit agreement	(26,000)	14,000
Additions to long-term debt	3,634	7,427
Reductions to long-term debt	(3,435)	(1,354)
Cash dividends paid	(5,617)	(5,375)
Purchase of treasury shares	0	(1,002)
Other	(1,755)	332
Net cash (used for) provided by financing activities	(33,173)	14,028
Cash and Cash Equivalents
Total decrease for the year	(2,445)	(34,442)
Balance at the beginning of the year	88,450	122,892
Balance at the end of the year	$ 86,005	$ 88,450