Unaudited Condensed Consolidated Statements of Cash Flows - USD ($) $ in Thousands	3 Months Ended
	Mar. 31, 2019	Mar. 31, 2018
Cash flows from operating activities
Net loss	$ (16,821)	$ (21,569)
Adjustments to reconcile net loss to net cash provided by operating activities:
Depreciation, depletion and amortization	46,548	51,420
Amortization of debt discount	700	655
Contract amortization	(1,686)	(1,420)
Accretion on asset retirement obligations	551	731
Equity-based compensation	233	177
Changes in operating assets and liabilities:
Accounts receivable	4,974	6,547
Due from/to affiliates, net	9,519	11,392
Inventories	(4,228)	(12,927)
Prepaid expenses and other assets	(9,235)	(6,424)
Prepaid royalties	5	2,004
Accounts payable	17,062	9,218
Accrued interest	7,380	13,315
Accrued expenses and other current liabilities	(6,157)	(1,466)
Other	322	53
Net cash provided by operating activities	49,167	51,706
Cash flows from investing activities
Investment in property, plant, equipment and development	(35,096)	(16,531)
Return of investment on financing arrangements with Murray Energy (affiliate)	823	778
Net cash used in investing activities	(34,273)	(15,753)
Cash flows from financing activities
Borrowings under revolving credit facility	21,000
Payments on revolving credit facility	(13,000)
Payments on long-term debt and finance lease obligations	(10,709)	(12,608)
Distributions paid	(4,856)	(4,510)
Payments on sale-leaseback and short-term financing arrangements	(4,112)	(2,461)
Net cash used in financing activities	(11,677)	(19,579)
Net increase in cash, cash equivalents, and restricted cash	3,217	16,374
Cash, cash equivalents, and restricted cash, beginning of period	269	2,179
Cash, cash equivalents, and restricted cash, end of period	$ 3,486	$ 18,553