Unaudited Condensed Consolidated Statements of Cash Flows - USD ($) $ in Thousands	9 Months Ended
	Sep. 30, 2022	Sep. 30, 2021
Operating activities
Net cash provided by operating activities	$ 54,929	$ 67,794
Investing activities
Expenditures for property, plant and equipment and acquisition of mineral interests	(42,004)	(35,534)
Proceeds from the sale of property, plant and equipment	2,824	547
Other	(58)	(52)
Net cash used for investing activities	(39,238)	(35,039)
Financing activities
Additions to long-term debt	1,664	3,633
Reductions of long-term debt	(2,118)	(3,131)
Net reductions to revolving credit agreements	(4,000)	(30,000)
Cash dividends paid	(4,488)	(4,200)
Net cash used for financing activities	(8,942)	(33,698)
Cash and cash equivalents
Total increase (decrease) for the period	6,749	(943)
Balance at the beginning of the period	86,005	88,450
Balance at the end of the period	$ 92,754	$ 87,507