Consolidated Balance Sheets - USD ($) $ in Thousands	Mar. 31, 2018	Dec. 31, 2017
Current assets:
Cash and cash equivalents	$ 14,178	$ 15,655
Revenue receivable	7,847	15,340
Joint interest billing receivable	3,024	6,597
Other receivable	6,000	7,750
Derivative asset	0	1,174
Deposit for surety bonds	11,100	8,300
Other current assets	1,960	2,125
Total current assets	44,109	56,941
Oil and gas properties:
Oil and gas properties, full cost method	1,351,048	1,369,861
Unevaluated oil and gas properties	16,918	21,854
Accumulated depreciation, depletion and amortization	(1,285,640)	(1,285,660)
Oil and gas properties, net	82,326	106,055
Other property and equipment	9,451	9,353
Accumulated depreciation of other property and equipment	(8,894)	(8,843)
Total property and equipment	82,883	106,565
Other assets	792	792
Total assets	127,784	164,298
Current liabilities:
Accounts payable to vendors	15,382	32,148
Advances from co-owners	1,181	1,730
Oil and gas revenue payable	18,451	19,344
Accrued interest	4,689	1,724
Asset retirement obligation	938	687
Derivative liability	718	731
Other accrued liabilities	11,318	6,476
Total current liabilities	52,677	62,840
Multi-draw Term Loan	28,131	27,963
Asset retirement obligation	2,304	30,623
Preferred stock dividend payable	11,563	10,278
Other long-term liabilities	567	131
Commitments and contingencies
Stockholders’ equity:
Preferred stock, $.001 par value; authorized 5,000 shares; issued and outstanding 1,495 shares	1	1
Common stock, $.001 par value; authorized 150,000 shares; issued and outstanding 25,550 and 25,521 shares, respectively	26	26
Paid-in capital	313,637	313,244
Accumulated other comprehensive income (loss)	(718)	278
Accumulated deficit	(564,755)	(562,484)
Total stockholders’ equity	(251,809)	(248,935)
Total liabilities and stockholders’ equity	127,784	164,298
10% Senior Secured Notes due 2021 | Senior Notes
Current liabilities:
10% Senior Secured Notes	9,788	9,821
10% Senior Secured PIK Notes due 2021 | Payment in Kind (PIK) Note
Current liabilities:
10% Senior Secured Notes	$ 274,563	$ 271,577