CONDENSED CONSOLIDATED STATEMENTS OF OPERATIONS PERCENTAGE	3 Months Ended		6 Months Ended
	Jun. 30, 2011	Jun. 30, 2010	Jun. 30, 2011	Jun. 30, 2010
Revenues
Lime and limestone operations (as a percent)	90.60%	95.30%	91.00%	94.50%
Natural gas interests (as a percent)	9.40%	4.70%	9.00%	5.50%
Total Revenues (as a percent)	100.00%	100.00%	100.00%	100.00%
Cost of revenues:
Labor and other operating expenses (as a percent)	62.60%	63.60%	62.00%	62.90%
Depreciation, depletion and amortization (as a percent)	9.20%	8.60%	9.70%	9.00%
Total Cost of revenues (as a percent)	71.80%	72.10%	71.70%	71.90%
Gross profit (as a percent)	28.20%	27.90%	28.30%	28.10%
Selling, general and administrative expenses (as a percent)	5.60%	5.20%	6.10%	6.00%
Operating profit (as a percent)	22.60%	22.70%	22.20%	22.00%
Other expense (income):
Interest expense (as a percent)	1.70%	1.70%	1.80%	1.80%
Other, net (as a percent)	(0.10%)	(0.10%)	(0.10%)	(0.10%)
Total Other expense (income) (as a percent)	1.50%	1.60%	1.70%	1.80%
Income before income taxes (as a percent)	21.00%	21.10%	20.50%	20.30%
Income tax expense (as a percent)	5.30%	6.10%	5.30%	5.80%
Net income (as a percent)	15.70%	14.90%	15.20%	14.40%