CONDENSED CONSOLIDATED STATEMENTS OF OPERATIONS (USD $) In Thousands, except Per Share data	3 Months Ended		6 Months Ended
	Jun. 30, 2011	Jun. 30, 2010	Jun. 30, 2011	Jun. 30, 2010
Revenues:
Sales	$ 766,716	$ 405,709	$ 1,173,291	$ 713,819
Miscellaneous income	6,284	4,913	8,443	8,852
Total revenues	773,000	410,622	1,181,734	722,671
Costs and expenses:
Cost of sales (exclusive of depreciation and depletion)	462,061	184,086	680,521	373,597
Depreciation and depletion	89,426	23,885	117,784	46,054
Selling, general and administrative	57,521	22,057	89,403	40,750
Postretirement benefits	10,343	10,361	20,610	20,730
Total costs and expenses	619,351	240,389	908,318	481,131
Operating income	153,649	170,233	273,416	241,540
Interest expense	(32,047)	(4,164)	(35,603)	(8,941)
Interest income	160	277	316	458
Other income	24,503		24,503
Income from continuing operations before income tax expense	146,265	166,346	262,632	233,057
Income tax expense	38,907	50,236	73,461	74,252
Income from continuing operations	107,358	116,110	189,171	158,805
Income (loss) from discontinued operations		53		(1,091)
Net income	$ 107,358	$ 116,163	$ 189,171	$ 157,714
Basic income per share:
Income from continuing operations (in dollars per share)	$ 1.72	$ 2.18	$ 3.24	$ 2.98
Discontinued operations (in dollars per share)				$ (0.02)
Net income (in dollars per share)	$ 1.72	$ 2.18	$ 3.24	$ 2.96
Diluted income per share:
Income from continuing operations (in dollars per share)	$ 1.71	$ 2.16	$ 3.22	$ 2.94
Discontinued operations (in dollars per share)				$ (0.02)
Net income (in dollars per share)	$ 1.71	$ 2.16	$ 3.22	$ 2.92
Dividends per share (in dollars per share)	$ 0.125	$ 0.125	$ 0.250	$ 0.225