Income Taxes (Details) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2021	Dec. 31, 2020	Dec. 31, 2019
Amount
Income taxes computed at the federal statutory rate	$ 9,769	$ 7,155	$ 6,489
(Reduction) increase in taxes resulting from:
Statutory depletion in excess of cost depletion	(1,389)	(1,266)	(1,200)
Research and development tax credit			(1,155)
State income taxes, net of federal income tax benefit	462	(262)	155
Disallowed executive compensation	456
Other	175	222	555
Income tax expense	$ 9,473	$ 5,849	$ 4,844
Percent of Pretax Income
Income taxes computed at the federal statutory rate (as a percent)	21.00%	21.00%	21.00%
(Reduction) increase in taxes resulting from (as a percent):
Statutory depletion in excess of cost depletion (as a percent)	(3.00%)	(3.70%)	(3.90%)
Research and development tax credit (as a percent)			(3.70%)
State income taxes, net of federal income tax benefit (as a percent)	1.00%	(0.80%)	0.50%
Disallowed executive compensation (as a percent)	1.00%
Other (as a percent)	0.40%	0.70%	1.80%
Income tax expense (as a percent)	20.40%	17.20%	15.70%
Deferred tax liabilities
Lime and limestone property, plant and equipment	$ 22,992	$ 21,297
Operating lease right-of-use assets	724	513
Natural gas interests drilling costs and equipment	387	519
Total	24,103	22,329
Deferred tax assets
Operating lease liabilities	740	511
Other	308	287
Total	1,048	798
Deferred tax liabilities, net, Total	23,055	21,531
Current income taxes:
Prepaid expenses and other current assets	543
Accrued expenses		990
Current income tax expense (benefit)	7,949	1,537	$ (4)
Deferred income tax expense	1,524	4,312	4,848
Income tax expense	9,473	$ 5,849	$ 4,844
Federal
Operating loss carry forwards
Net operating loss carryforwards	$ 0