Consolidated Balance Sheets - USD ($) $ in Thousands	Dec. 31, 2017	Dec. 31, 2016
Current assets:
Cash and cash equivalents	$ 15,655	$ 28,312
Revenue receivable	15,340	10,294
Joint interest billing receivable	6,597	7,632
Other receivable	7,750	0
Derivative asset	1,174	0
Deposit for surety bonds	8,300	0
Other current assets	2,125	2,353
Total current assets	56,941	48,591
Oil and gas properties:
Oil and gas properties, full cost method	1,369,861	1,323,333
Unevaluated oil and gas properties	21,854	9,015
Accumulated depreciation, depletion and amortization	(1,285,660)	(1,243,286)
Oil and gas properties, net	106,055	89,062
Other property and equipment	9,353	10,951
Accumulated depreciation of other property and equipment	(8,843)	(10,109)
Total property and equipment	106,565	89,904
Other assets, net of accumulated amortization of $0 and $4,385, respectively	792	6,365
Total assets	164,298	144,860
Current liabilities:
Accounts payable to vendors	36,179	25,265
Advances from co-owners	1,730	2,330
Oil and gas revenue payable	19,344	22,146
Accrued interest	1,724	2,047
Asset retirement obligation	687	4,160
Derivative liability	731	3,947
10% Senior Unsecured Notes due 2017	0	22,568
Other accrued liabilities	2,445	3,938
Total current liabilities	62,840	86,401
Multi-draw Term Loan	27,963	7,249
Asset retirement obligation	30,623	32,450
Other long-term liabilities	10,409	6,027
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 25,521 and 21,197 shares, respectively	26	21
Paid-in capital	313,244	304,341
Accumulated other comprehensive income (loss)	278	(4,750)
Accumulated deficit	(562,484)	(550,708)
Total stockholders’ equity	(248,935)	(251,095)
Total liabilities and stockholders’ equity	164,298	144,860
10% Senior Secured Notes due 2021 | Senior Notes
Current liabilities:
10% Senior Secured Notes	9,821	15,228
10% Senior Secured PIK Notes due 2021 | Payment in Kind (PIK) Note
Current liabilities:
10% Senior Secured Notes	$ 271,577	$ 248,600