Condensed Consolidated Balance Sheets - USD ($) $ in Thousands	Sep. 30, 2019	Dec. 31, 2018
Current assets:
Cash and cash equivalents	$ 98,348	$ 6,313
Equity securities		47,082
Accounts receivable:
Oil, natural gas and natural gas liquids revenues	21,538	40,176
Other	481	4,496
Derivative asset	8,745	15,452
Other current assets	406	2,314
Total current assets	129,518	115,833
Oil and natural gas properties, net of accumulated depreciation, depletion and amortization; September 30, 2019, $19,362; December 31, 2018, $12,950	142,471	405,688
Assets held for sale	9,284
Long–term derivative asset	1,933	8,499
Other assets	6,679	4,474
Total assets	289,885	534,494
Current liabilities:
Accounts payable and accrued liabilities	24,143	26,146
Derivative liability		1,165
Other current liabilities	684
Total current liabilities	24,827	27,311
Asset retirement obligations	101,374	117,529
Long-term debt, net		115,000
Liabilities held for sale	2,759
Other long–term liabilities	1,638	1,036
Commitments and contingencies (Note 11)
Mezzanine equity	135	79
Stockholders’ equity:
Common stock – $0.01 par value; 65,000,000 shares authorized; 10,213,888 shares issued and 10,179,379 shares outstanding as of September 30, 2019; 10,054,816 shares issued and 10,042,468 shares outstanding as of December 31, 2018	102	100
Additional paid-in capital	251,834	249,717
Treasury stock at cost – 34,509 shares at September 30, 2019; 12,348 shares at December 31, 2018	(542)	(247)
Retained earnings (accumulated deficit)	(92,242)	23,969
Total stockholders’ equity	159,152	273,539
Total liabilities and equity	$ 289,885	$ 534,494