Consolidated Statements of Cash Flows - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2018	Dec. 31, 2017
Cash flows from operating activities:
Net income (loss)	$ 12,779	$ 6,399
Items not involving cash:
Depreciation, depletion and amortization	8,108	2,544
Accretion of asset retirement obligations	868	307
Unrealized commodity derivative gain	8,742	(2,158)
Warrant derivative gain	(225)	(3,133)
Stock-based compensation expense	1,133	1,106
Investment in affiliates gain	(7,734)	(1,128)
Amortization of debt issuance costs	966	176
Other		(109)
Net change in:
Accounts receivable	545	(812)
Prepaid expenses, deposits and other current assets	1,067	(477)
Accounts payable, accrued liabilities and firm transportation contracts	2,472	1,205
Other non-current assets	(392)
Net cash provided by operating activities	10,845	3,920
Cash flows from investing activities:
Development and acquisition of properties and equipment	(2,995)	(1,591)
Acquisition of oil and gas properties, asset acquisitions (Note 3)	(46,980)
Acquisition of oil and gas properties, business combinations, net of cash received (Note 3)	(20,461)
Other non-current assets		(145)
Investment in affiliates		(6,797)
Net cash used in investing activities	(70,436)	(8,533)
Cash flows from financing activities:
Vested restricted stock and performance units exchanged for tax withholding	(197)	(399)
Proceeds from credit facilities and notes payable	118,628	7,210
Proceeds from preferred shares	5,000
Payments on credit facilities and notes payable	(64,150)	(1,300)
Payments of debt issuance costs	(718)
Contributions from non-controlling interests	5,164
Distributions to non-controlling interests	(50)	(106)
Net cash provided by financing activities	63,677	5,405
Net increase in cash and cash equivalents	4,086	792
Cash and cash equivalents, beginning of period	1,650	858
Cash and cash equivalents, end of period	$ 5,736	$ 1,650