Condensed Consolidated Balance Sheets (Current Period Unaudited) - USD ($) $ in Thousands	Jun. 30, 2021	Dec. 31, 2020
Current assets:
Cash and cash equivalents	$ 7,964	$ 2,775
Accounts receivable:
Joint owners, net	1,093	1,255
Oil and gas production sales	12,600	8,794
Other	305	0
Total accounts receivable	13,998	10,049
Derivative asset - short-term	0	9,639
Other current assets	966	1,588
Total current assets	22,928	24,051
Proved oil and gas properties, full cost method	1,164,825	1,167,333
Other property and equipment	39,204	39,456
Total	1,204,029	1,206,789
Less accumulated depreciation, depletion, amortization and impairment	(1,091,722)	(1,083,843)
Total property and equipment, net	112,307	122,946
Operating lease right-of-use assets	194	228
Derivative asset, long-term	0	10,281
Other assets	255	255
Total assets	135,684	157,761
Current liabilities:
Accounts payable	2,067	6,074
Joint interest oil and gas production payable	11,607	8,795
Accrued interest	286	86
Accrued expenses	833	230
Right of use liability	41	53
Derivative liabilities - short-term	3,006	480
Termination of derivative contracts	9,944	0
Current maturities of long-term debt	209,244	202,751
Other current liabilities	214	850
Total current liabilities	237,242	219,319
Operating lease right-of-use liabilities	128	150
Future site restoration	4,771	7,360
Total liabilities	245,839	230,728
Commitments and contingencies (Note 11)
Stockholders’ Equity:
Preferred stock, par value $0.01 per share – authorized 1,000,000 shares; -0- shares issued and outstanding	0	0
Common stock, par value $0.01 per share, authorized 20,000,000 shares; 8,421,910 issued and outstanding at June 30, 2021 and December 31, 2020	84	84
Additional paid-in capital	429,983	429,476
Accumulated deficit	(540,222)	(502,527)
Total stockholders' deficit	(110,155)	(72,967)
Total liabilities and stockholders’ equity	135,684	157,761
Debt Instruments Excluding PPP Loan [Member]
Current liabilities:
Long-term debt – less current maturities	2,362	2,515
Paycheck Protection Program, CARES Act [Member]
Current liabilities:
Long-term debt – less current maturities	$ 1,336	$ 1,384