Consolidated Statements of Cash Flows - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2020	Dec. 31, 2019
OPERATING ACTIVITIES:
Net loss	$ (6,220)	$ (59,854)
Deferred income taxes	(2,060)	(21,822)
Equity (income) loss – Sunrise Energy	(1,054)	527
Cash distribution - Sunrise Energy	1,125	0
DD&A	39,644	48,572
Asset impairment	1,799	77,882
Loss (gain) on sale of assets	38	(90)
Unrealized gain on marketable securities	(14)	(593)
Gain on sale of royalty interests in oil properties	0	(2,949)
Amortization and write off of deferred financing costs	2,296	2,095
Accretion of ARO	1,381	1,272
Stock-based compensation	1,211	1,833
Change in current assets and liabilities:
Accounts receivable	11,166	(7,312)
Inventory	2,893	(8,603)
Parts and supplies	2,872	(2,130)
Prepaid income taxes	1,562	1,044
Accounts payable and accrued liabilities	(1,405)	3,608
Other	(3,048)	2,577
Cash provided by operating activities	52,576	38,243
INVESTING ACTIVITIES:
Capital expenditures	(20,688)	(35,533)
Proceeds from sale of royalty interests in oil properties	0	2,949
Proceeds from sale of equipment	56	134
Proceeds from sale of marketable securities	2,310	2,007
Proceeds from maturities of certificates of deposit	245	245
Investment in Sunrise Energy	(113)	0
Cash used in investing activities	(18,190)	(30,198)
FINANCING ACTIVITIES:
Payments on bank debt	(49,662)	(42,063)
Borrowings of bank debt	7,250	33,750
Proceeds from PPP note	10,000	0
Deferred financing costs	(1,903)	(1,192)
Taxes paid on vesting of RSUs	(75)	(358)
Dividends	(1,236)	(4,965)
Cash used in financing activities	(35,626)	(14,828)
Decrease in cash, cash equivalents, and restricted cash	(1,240)	(6,783)
Cash, cash equivalents, and restricted cash, beginning of year	13,311	20,094
Cash, cash equivalents, and restricted cash, end of year	12,071	13,311
CASH, CASH EQUIVALENTS, AND RESTRICTED CASH:
Cash and cash equivalents	8,041	8,799
Restricted cash	4,030	4,512
Cash, Cash Equivalents, Restricted Cash and Restricted Cash Equivalents, Ending Balance	12,071	13,311
SUPPLEMENTAL CASH FLOW INFORMATION:
Cash paid for interest	10,791	11,639
SUPPLEMENTAL NON-CASH FLOW INFORMATION:
Change in capital expenditures included in accounts payable and prepaid expense	1,199	5,849
Right-of-use assets acquired by operating lease	0	800
Interest Rate Swap [Member]
OPERATING ACTIVITIES:
Change in fair value of derivative	68	2,186
Fuel Hedge [Member]
OPERATING ACTIVITIES:
Change in fair value of derivative	$ 322	$ 0