Consolidated Balance Sheets - USD ($) $ in Thousands	Dec. 31, 2020	Dec. 31, 2019
Current assets
Cash and cash equivalents	$ 22,130	$ 4,275
Restricted cash - other	6,136	1,693
Accounts receivable, net	19,576	28,644
Derivative contracts	0	114
Prepaid expenses	2,890	3,342
Other current assets	80	538
Total current assets	50,812	38,606
Oil and natural gas properties, using full cost method of accounting
Proved	1,463,950	1,484,359
Unproved	17,964	24,603
Less: accumulated depreciation, depletion and impairment	(1,375,692)	(1,129,622)
Net oil and natural gas properties capitalized costs	106,222	379,340
Other property, plant and equipment, net	103,118	188,603
Other assets	680	1,140
Total assets	260,832	607,689
Current liabilities
Accounts payable and accrued expenses	51,426	64,937
Asset retirement obligations	16,467	22,119
Other current liabilities	984	1,367
Total current liabilities	68,877	88,423
Long-term debt	20,000	57,500
Asset retirement obligations	40,701	52,897
Other long-term obligations	3,188	6,417
Total liabilities	132,766	205,237
Commitments and contingencies
Stockholders’ Equity
Common stock, $0.001 par value; 250,000 shares authorized; 35,928 issued and outstanding at December 31, 2020 and 35,772 issued and outstanding at December 31, 2019	36	36
Warrants	88,520	88,520
Additional paid-in capital	1,062,220	1,059,253
Accumulated deficit	(1,022,710)	(745,357)
Total stockholders’ equity	128,066	402,452
Total liabilities and stockholders’ equity	$ 260,832	$ 607,689