Consolidated Statements of Cash Flows (Unaudited) - USD ($) $ in Thousands	3 Months Ended
	Mar. 31, 2020	Mar. 31, 2019
Cash flows from operating activities
Net income (loss)	$ 4,917	$ (103,540)
Adjustments to reconcile net income (loss) to net cash provided by operating activities
Depreciation, depletion and amortization	23,012	23,715
Derivative (gains) losses	(78,380)	51,016
Impairment of oil and gas assets	71,371	49,722
Impairment of other assets	153	0
(Gain) loss on sale of assets	(102)	1
Other	2,338	542
Change in assets and liabilities
Accounts receivable	4,835	7,910
Inventories	675	207
Prepaid expenses and other assets	(1,011)	256
Accounts payable and accrued liabilities	(14,870)	(16,689)
Revenue distribution payable	(619)	(5,511)
Deferred compensation	564	925
Net cash provided by operating activities	12,883	8,554
Cash flows from investing activities
Expenditures for property, plant, and equipment and oil and natural gas properties	(49,053)	(64,044)
Proceeds from asset dispositions	3,209	0
Proceeds from derivative instruments, net	9,174	515
Net cash used in investing activities	(36,670)	(63,529)
Cash flows from financing activities
Proceeds from long-term debt	15,000	30,000
Repayment of long-term debt	(313)	(171)
Principal payments under financing lease obligations	(105)	(699)
Payment of debt issuance costs and other financing fees	(93)	(20)
Treasury stock purchased	(6)	(463)
Net cash provided by financing activities	14,483	28,647
Net decrease in cash and cash equivalents	(9,304)	(26,328)
Cash and cash equivalents, at beginning of period	22,595	37,446
Cash and cash equivalents, at end of period	$ 13,291	$ 11,118