Consolidated Balance Sheets (USD $) In Thousands, unless otherwise specified	Mar. 31, 2014	Dec. 31, 2013	Mar. 31, 2013
Current Assets:
Cash and cash equivalents	$ 35,801	$ 42,437	$ 37,260
Accounts receivable, net	242,587	245,421	202,150
Inventories, net	354,718	347,307	347,641
Current deferred income tax benefits	73,320	74,821	79,485
Other current assets	51,788	45,380	49,197
Total Current Assets	758,214	755,366	715,733
Property, plant and equipment	4,001,505	3,976,884	3,824,638
Allowances for depreciation, depletion and amortization	(2,207,969)	(2,177,643)	(2,092,551)
Net property, plant and equipment	1,793,536	1,799,241	1,732,087
Goodwill	616,621	616,621	616,350
Other intangibles, net	47,743	48,591	49,548
Other noncurrent assets	39,143	40,007	41,057
Total Assets	3,255,257	3,259,826	3,154,775
Current Liabilities:
Bank overdraft		2,556
Accounts payable	98,775	103,600	77,080
Accrued salaries, benefits and payroll taxes	12,904	18,114	12,387
Pension and postretirement benefits	2,356	2,026	4,091
Accrued insurance and other taxes	27,265	29,103	27,470
Current maturities of long-term debt and short-term facilities	12,403	12,403	5,677
Accrued interest	18,077	7,349	18,479
Other current liabilities	21,978	35,398	23,506
Total Current Liabilities	193,758	210,549	168,690
Long-term debt	1,055,541	1,018,518	1,072,850
Pension, postretirement and postemployment benefits	80,457	78,489	184,287
Noncurrent deferred income taxes	272,346	279,999	230,109
Other noncurrent liabilities	108,862	97,352	88,782
Total Liabilities	1,710,964	1,684,907	1,744,718
Equity:
Common stock, par value $0.01 per share	462	461	459
Preferred stock, par value $0.01 per share
Additional paid-in capital	442,551	432,792	421,024
Accumulated other comprehensive loss	(42,744)	(44,114)	(104,948)
Retained earnings	1,108,516	1,148,738	1,055,256
Total Shareholders' Equity	1,508,785	1,537,877	1,371,791
Noncontrolling interests	35,508	37,042	38,266
Total Equity	1,544,293	1,574,919	1,410,057
Total Liabilities and Equity	$ 3,255,257	$ 3,259,826	$ 3,154,775