CONDENSED CONSOLIDATED STATEMENTS OF OPERATIONS - USD ($) $ in Thousands	3 Months Ended		9 Months Ended
	Sep. 30, 2016	Sep. 30, 2015	Sep. 30, 2016	Sep. 30, 2015
Revenues
Lime and limestone operations	$ 38,096	$ 36,452	$ 103,626	$ 97,593
Natural gas interests	554	577	1,490	1,950
Total revenues	38,650	37,029	105,116	99,543
Cost of revenues:
Labor and other operating expenses	24,064	22,695	67,603	64,563
Depreciation, depletion and amortization	4,017	3,967	11,855	11,736
Total cost of revenues	28,081	26,662	79,458	76,299
Gross profit	10,569	10,367	25,658	23,244
Selling, general and administrative expenses	2,482	2,467	7,213	7,266
Operating profit	8,087	7,900	18,445	15,978
Other expenses (income):
Interest expense	63	57	185	969
Other (income) expense, net	(115)	(54)	(238)	651
Total other expense (income)	(52)	3	(53)	1,620
Income before income taxes	8,139	7,897	18,498	14,358
Income tax expense	2,058	2,221	4,664	3,758
Net income	$ 6,081	$ 5,676	$ 13,834	$ 10,600
Net income per share of common stock:
Basic (in dollars per share)	$ 1.09	$ 1.01	$ 2.48	$ 1.89
Diluted (in dollars per share)	1.09	1.01	2.48	1.89
Cash dividends per share of common stock (in dollars per share)	$ 0.125	$ 0.125	$ 0.375	$ 0.375