CONDENSED CONSOLIDATED STATEMENTS OF OPERATIONS AND COMPREHENSIVE INCOME - USD ($) shares in Thousands, $ in Thousands	3 Months Ended		6 Months Ended
	Jun. 30, 2015	Jun. 30, 2014	Jun. 30, 2015	Jun. 30, 2014
CONDENSED CONSOLIDATED STATEMENTS OF OPERATIONS AND COMPREHENSIVE INCOME
Revenue	$ 244,148	$ 320,850	$ 561,701	$ 639,916
Costs and expenses
Cost of product sold (exclusive of depreciation, depletion, amortization, and accretion, shown separately)	222,443	270,121	486,760	542,060
Depreciation and depletion	19,310	29,200	43,846	56,128
Amortization of port access contract rights	928	0	1,855	0
Accretion	3,348	4,088	6,890	8,217
Derivative financial instruments	2,761	(2,803)	7,546	(15,537)
Selling, general and administrative expenses	12,511	12,483	23,760	24,924
Goodwill impairment	33,355	0	33,355	0
Other operating costs	304	333	517	573
Total costs and expenses	294,960	313,422	604,529	616,365
Operating income (loss)	(50,812)	7,428	(42,828)	23,551
Other income (expense)
Interest income	50	61	99	185
Interest expense	(12,621)	(13,813)	(25,289)	(51,807)
Other, net	244	233	(93)	(231)
Total other income (expense)	(12,327)	(13,519)	(25,283)	(51,853)
Income (loss) before income tax provision and earnings from unconsolidated affiliates	(63,139)	(6,091)	(68,111)	(28,302)
Income tax benefit (expense)	9,866	3,489	10,146	9,979
Earnings from unconsolidated affiliates, net of tax	376	454	388	549
Net income (loss)	(52,897)	(2,148)	(57,577)	(17,774)
Other comprehensive income (loss)
Postretirement medical plan amortization of prior service costs	313	247	626	494
Income tax on postretirement medical plan	(116)	(89)	(232)	(178)
Other comprehensive income (loss)	197	158	394	316
Total comprehensive income (loss)	$ (52,700)	$ (1,990)	$ (57,183)	$ (17,458)
Income (loss) per common share
Basic	$ (0.87)	$ (0.04)	$ (0.94)	$ (0.29)
Diluted	$ (0.87)	$ (0.04)	$ (0.94)	$ (0.29)
Weighted-average shares outstanding - basic	61,028	60,818	60,982	60,779
Weighted-average shares outstanding - diluted	61,028	60,818	60,982	60,779