Unaudited Condensed Consolidated Balance Sheets (Current Period) - USD ($) $ in Thousands	Mar. 31, 2019	Dec. 31, 2018
Current assets
Cash and cash equivalents	$ 1,939	$ 6,951
Accounts receivable	27,285	10,729
Inventories	15,027	14,185
Prepaid expenses	1,958	3,154
Total current assets	46,209	35,019
Property, plant and equipment, net	156,343	149,205
Advanced coal royalties	3,126	3,045
Other assets	1,013	975
Total Assets	206,691	188,244
Current liabilities
Accounts payable	15,247	16,393
Accrued expenses	9,124	8,094
Asset retirement obligations	292	71
Current portion of long-term debt	5,000	5,000
Other	116	287
Total current liabilities	29,779	29,845
Asset retirement obligations	12,657	12,707
Long-term debt, net	13,737	4,474
Deferred tax liability	1,450	109
Other long-term liabilities	182
Total liabilities	57,805	47,135
Commitments and contingencies
Stockholders' Equity
Preferred stock, $0.01 par value, 50,000,000 shares authorized, none issued and outstanding
Common stock, $0.01 par value, 260,000,000 shares authorized, 40,832,890 and 40,082,467 shares issued and outstanding, respectively	408	401
Additional paid-in capital	151,813	150,926
Accumulated deficit	(3,335)	(10,218)
Total stockholders' equity	148,886	141,109
Total Liabilities and Stockholders' Equity	$ 206,691	$ 188,244