Consolidated Statements of Cash Flows - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2020	Dec. 31, 2019
Cash Flows from Operating Activities:
Net Income (Loss)	$ (309,382)	$ 114,656
Adjustments to reconcile net income to net cash provided by operation activities -
Write-down of oil and gas properties	355,948	0
Depreciation, depletion, and amortization	64,564	95,915
Accretion of asset retirement obligation	354	329
Deferred income taxes	21,390	(22,101)
Stock-based compensation expense	4,557	6,148
Gain (Loss) on Sale of Derivatives	(61,304)	(24,242)
Cash Received (Paid) On Settlements of Derivative Contracts	78,421	24,631
Asset Retirement Obligation, Cash Paid to Settle	(94)	(83)
Write off of Deferred Debt Issuance Cost	557	82
Other Noncash Income (Expense)	3,061	2,930
Change in assets and liabilities-
(Increase) decrease in accounts receivable and other assets	9,011	11,605
Increase (decrease) in accounts payable and accrued liabilities	(977)	(7,100)
Increase (decrease) in income taxes payable	480	(519)
Increase (decrease) in accrued interest	(414)	(116)
Net Cash Provided by Operating Activities	165,212	203,173
Cash Flows from Investing Activities:
Additions to property and equipment	(114,738)	(282,660)
Acquisition of properties	(4,544)	0
Proceeds from (adjustments to) the sale of property and equipment	4,777	(96)
Payments for (Proceeds from) Other Investing Activities	(826)	(5,112)
Net Cash Used in Investing Activities	(115,331)	(287,868)
Cash Flows from Financing Activities:
Proceeds from bank borrowings	107,000	381,000
Payments of bank borrowings	(156,000)	(297,000)
Purchase of treasury shares	(90)	(412)
Payments of debt issuance costs	(31)	0
Net Cash Provided by (Used in) Financing Activities	(49,121)	83,588
Cash, Cash Equivalents, Restricted Cash and Restricted Cash Equivalents, Period Increase (Decrease), Excluding Exchange Rate Effect	760	(1,107)
Total Cash, Cash Equivalents, Restricted Cash and Restricted Cash Equivalents	2,118	1,358
Supplemental Disclosures of Cash Flows Information:
Cash paid during period for interest, net of amounts capitalized	28,929	34,408
Increase (decrease) in accrued payables for capital	$ (19,365)	$ (21,584)