CONDENSED CONSOLIDATED STATEMENTS OF CASH FLOWS - USD ($) $ in Thousands	6 Months Ended
	Jun. 30, 2015	Jun. 30, 2014
Cash flows from operating activities
Net income (loss)	$ (57,577)	$ (17,774)
Adjustments to reconcile net income (loss) to net cash provided by operating activities:
Depreciation and depletion	43,846	56,128
Amortization of port access contract rights	1,855	0
Accretion	6,890	8,217
Goodwill impairment	33,355	0
Earnings from unconsolidated affiliates, net of tax	(388)	(549)
Distributions of income from unconsolidated affiliates	0	1,250
Deferred income taxes	(10,146)	(9,979)
Equity-based compensation expense	2,815	3,779
Derivative mark-to-market (gains) losses	7,546	(15,537)
Cash received (paid) for derivative financial instruments	(894)	11,898
Premium payments on derivative financial instruments	(5,813)	0
Non-cash interest expense related to early retirement of debt and refinancings	0	7,338
Other	6,406	6,123
Changes in operating assets and liabilities:
Accounts receivable	34,485	(140)
Inventories, net	1,089	(4,110)
Due to or from related parties	(2,247)	(1,795)
Other assets	(4,196)	(2,459)
Accounts payable and accrued expenses	(41,593)	(6,448)
Asset retirement obligations	(546)	(561)
Net cash provided by (used in) operating activities	14,887	35,381
Investing activities
Purchases of property, plant and equipment	(14,782)	(7,146)
Investments in marketable securities	0	(8,159)
Maturity and redemption of investments	0	88,845
Investment in development projects	(1,500)	(1,500)
Payment of restricted cash	(6,500)	0
Other	(184)	222
Net cash provided by (used in) investing activities	(22,966)	72,262
Financing activities
Principal payments on federal coal leases	(63,970)	0
Issuance of senior notes	0	200,000
Repayment of senior notes	0	(300,000)
Payment of deferred financing costs	(341)	(13,598)
Other	(817)	(194)
Net cash provided by (used in) financing activities	(65,128)	(113,792)
Net increase (decrease) in cash and cash equivalents	(73,207)	(6,149)
Cash and cash equivalents at beginning of period	168,745	231,633
Cash and cash equivalents at end of period	95,538	225,484
Supplemental cash flow disclosures
Interest paid	26,134	19,477
Income taxes paid (refunded)	3,972	(5,798)
Supplemental noncash investing and financing activities
Capital expenditures included in accounts payable	8,744	915
Assets acquired under capital leases	$ 0	$ 1,209