Unaudited Condensed Consolidated Balance Sheets (USD $) In Thousands, unless otherwise specified	Jun. 30, 2014	Dec. 31, 2013	Jun. 30, 2013
ASSETS
Cash and cash equivalents	$ 60,907	$ 95,390	$ 85,058
Accounts receivable, net	85,001	120,789	81,271
Accounts receivable from affiliates	36,351	32,636	29,029
Inventories, net	188,148	184,445	167,470
Deferred income taxes	12,740	14,452	13,701
Prepaid expenses and other	23,195	13,578	16,111
Total current assets	406,342	461,290	392,640
Property, plant and equipment, net	254,362	219,256	185,626
Coal supply agreements and other intangibles, net	57,929	59,685	65,666
Other non-current assets	70,160	69,725	54,185
Total assets	788,793	809,956	698,117
LIABILITIES AND EQUITY
Accounts payable	99,319	133,016	90,334
Revolving credit agreements of subsidiaries - not guaranteed by the parent company	74,524	23,460	27,264
Current maturities of long-term debt of subsidiaries - not guaranteed by the parent company	7,877	7,859	6,969
Accrued payroll	14,837	29,030	18,378
Other current liabilities	37,868	44,754	30,510
Total current liabilities	234,425	238,119	173,455
Long-term debt of subsidiaries - not guaranteed by the parent company	147,257	152,431	129,687
Mine closing reserves	35,930	29,764	28,928
Pension and other postretirement obligations	7,355	7,648	14,573
Long-term deferred income taxes	23,026	24,786	22,961
Other long-term liabilities	66,013	59,428	60,487
Total liabilities	514,006	512,176	430,091
Common stock:
Capital in excess of par value	0	941	4,185
Retained earnings	279,922	301,227	275,662
Accumulated other comprehensive loss	(12,762)	(12,259)	(19,858)
Total stockholders' equity	274,787	297,780	268,026
Total liabilities and equity	788,793	809,956	698,117
Common Class A
Common stock:
Common stock	6,046	6,290	6,455
Common Class B
Common stock:
Common stock	$ 1,581	$ 1,581	$ 1,582