CONDENSED CONSOLIDATED STATEMENTS OF OPERATIONS - USD ($) $ in Thousands	3 Months Ended
	Mar. 31, 2019	Mar. 31, 2018
Revenues
Total revenues	$ 37,799	$ 35,287
Cost of revenues
Labor and other operating expenses	25,038	24,073
Depreciation, depletion and amortization	4,068	4,177
Total cost of revenues	29,106	28,250
Gross profit	8,693	7,037
Selling, general and administrative expenses	2,673	2,501
Operating profit	6,020	4,536
Other (income) expense
Interest expense	62	62
Interest and other income, net	(492)	(353)
Total other (income) expense	(430)	(291)
Income before income tax expense	6,450	4,827
Income tax expense	1,322	565
Net income	$ 5,128	$ 4,262
Net income per share of common stock
Basic (in dollars per share)	$ 0.91	$ 0.76
Diluted (in dollars per share)	$ 0.91	$ 0.76
Lime and limestone operations
Revenues
Total revenues	$ 37,465	$ 34,714
Natural gas interests
Revenues
Total revenues	$ 334	$ 573