Income Taxes (Details) (USD $) In Thousands, unless otherwise specified	12 Months Ended
	Dec. 31, 2013	Dec. 31, 2012	Dec. 31, 2011
Income Taxes
Current income tax expense	$ 3,240	$ 3,547	$ 4,398
Deferred income tax expense	1,793	2,131	3,560
Income tax expense	5,033	5,678	7,958
Amount
Income taxes computed at the federal statutory rate	6,942	7,735	10,550
(Reduction) increase in taxes resulting from:
Statutory depletion in excess of cost depletion	(1,965)	(2,048)	(2,366)
Manufacturing deduction	(299)	(335)	(308)
State income taxes, net of federal income tax benefit	132	331	24
Other	223	(5)	58
Income tax expense	5,033	5,678	7,958
Percent of Pretax Income
Income taxes computed at the federal statutory rate (as a percent)	35.00%	35.00%	35.00%
(Reduction) increase in taxes resulting from (as a percent):
Statutory depletion in excess of cost depletion (as a percent)	(9.90%)	(9.30%)	(7.90%)
Manufacturing deduction (as a percent)	(1.50%)	(1.50%)	(1.00%)
State income taxes, net of federal income tax benefit (as a percent)	0.70%	1.50%	0.10%
Other (as a percent)	1.10%	0.00%	0.20%
Income tax expense (as a percent)	25.40%	25.70%	26.40%
Deferred tax liabilities
Lime and limestone property, plant and equipment	20,614	19,306
Natural gas interests drilling costs and equipment	3,680	3,952
Other	344	344
Total	24,638	23,602
Deferred tax assets
Alternative minimum tax credit carry forwards	5,866	6,489
Minimum pension liability	299	412
Fair value liability of interest rate hedges	557	956
Other	635	769
Total	7,357	8,626
Net deferred tax liabilities	17,281	14,976
Current income taxes:
Accrued expense	0	307
Prepaid expenses and other current assets	203	0
Deferred income taxes:
Prepaid expenses and other current assets	518	678
Deferred tax liabilities, net	17,799	15,654
Federal
Operating loss carry forwards
Net operating loss	$ 0