Unaudited Condensed Consolidated Balance Sheets (USD $) In Thousands, unless otherwise specified	Jun. 30, 2013	Dec. 31, 2012	Jun. 30, 2012
ASSETS
Cash and cash equivalents	$ 85,058	$ 139,855	$ 160,098
Accounts receivable, net	81,271	121,147	75,986
Accounts receivable from affiliates	29,029	28,144	3,993
Inventories, net	167,470	169,440	173,913
Deferred income taxes	13,701	15,335	17,724
Prepaid expenses and other	16,111	12,921	25,834
Current assets of discontinued operations	0	0	817,098
Total current assets	392,640	486,842	1,274,646
Property, plant and equipment, net	185,626	182,985	137,012
Goodwill	3,973	6,399	0
Coal supply agreements and other intangibles, net	61,693	63,353	56,851
Other non-current assets	54,185	36,727	32,979
Long-term assets of discontinued operations	0	0	212,220
Total assets	698,117	776,306	1,713,708
LIABILITIES AND EQUITY
Accounts payable	90,334	127,469	86,859
Revolving credit agreements of subsidiaries - not guaranteed by the parent company	27,264	35,288	62,708
Current maturities of long-term debt of subsidiaries - not guaranteed by the parent company	6,969	6,961	6,960
Accrued payroll	18,378	24,288	13,534
Other current liabilities	30,510	33,163	36,562
Current liabilities of discontinued operations	0	0	483,753
Total current liabilities	173,455	227,169	690,376
Long-term debt of subsidiaries - not guaranteed by the parent company	129,687	135,448	95,251
Mine closing reserves	28,928	29,033	18,531
Pension and other postretirement obligations	23,166	24,394	25,577
Long-term deferred income taxes	22,961	27,313	12,384
Other long-term liabilities	51,894	51,618	43,360
Long-term liabilities of discontinued operations	0	0	211,521
Total liabilities	430,091	494,975	1,097,000
Common stock:
Capital in excess of par value	4,185	24,612	24,364
Retained earnings	318,885	313,450	657,518
Accumulated other comprehensive loss	(63,081)	(65,084)	(74,490)
Total stockholders' equity	268,026	281,331	615,781
Noncontrolling interest	0	0	927
Total equity	268,026	281,331	616,708
Total liabilities and equity	698,117	776,306	1,713,708
Common Class A
Common stock:
Common stock	6,455	6,771	6,799
Common Class B
Common stock:
Common stock	$ 1,582	$ 1,582	$ 1,590