CONDENSED CONSOLIDATED STATEMENTS OF OPERATIONS Percentage	3 Months Ended		9 Months Ended
	Sep. 30, 2012	Sep. 30, 2011	Sep. 30, 2012	Sep. 30, 2011
Revenues
Lime and limestone operations (as a percent)	95.40%	91.00%	94.90%	91.00%
Natural gas interests (as a percent)	4.60%	9.00%	5.10%	9.00%
Total revenues (as a percent)	100.00%	100.00%	100.00%	100.00%
Cost of revenues:
Labor and other operating expenses (as a percent)	66.30%	59.10%	66.00%	61.00%
Depreciation, depletion and amortization (as a percent)	11.00%	8.90%	10.30%	9.40%
Total cost of revenues (as a percent)	77.30%	68.00%	76.30%	70.40%
Gross profit (as a percent)	22.70%	32.00%	23.70%	29.60%
Selling, general and administrative expenses (as a percent)	6.10%	5.90%	6.30%	6.00%
Operating profit (as a percent)	16.60%	26.10%	17.40%	23.60%
Other expense (income):
Interest expense (as a percent)	1.60%	1.50%	1.60%	1.70%
Other, net (as a percent)	(0.10%)	(0.10%)	(0.10%)	(0.10%)
Total other expense (income) (as a percent)	1.50%	1.40%	1.50%	1.60%
Income before income taxes (as a percent)	15.10%	24.70%	15.90%	22.00%
Income tax expense (as a percent)	3.50%	6.70%	4.10%	5.80%
Net income (as a percent)	11.60%	18.00%	11.80%	16.20%