Quarterly report pursuant to Section 13 or 15(d)

Segment Information (Segment Activity) (Details)

v3.21.1
Segment Information (Segment Activity) (Details) - USD ($)
 3 Months Ended
Mar. 31, 2021
Mar. 31, 2020
Segment Reporting Information [Line Items]    
Revenues-crude oil and natural gas sales $ 39,774,000 $ 18,389,000
Depreciation, depletion and amortization 4,148,000 3,103,000
Impairment of proved crude oil and natural gas properties 0 30,625,000
Bad debt expense and other 101,000 810,000
Operating income (loss) 14,343,000 (26,683,000)
Derivative instruments gain (loss), net (5,954,000) 7,339,000
Other, net 4,580,000 (31,000)
Income tax expense (benefit) 3,086,000 33,478,000
Additions to crude oil and natural gas properties and equipment - accrual 2,515,000 9,421,000
Operating Segments [Member] | Gabon Segment [Member]    
Segment Reporting Information [Line Items]    
Revenues-crude oil and natural gas sales 39,774,000 18,389,000
Depreciation, depletion and amortization 4,121,000 3,072,000
Impairment of proved crude oil and natural gas properties   30,625,000
Bad debt expense and other   810,000
Operating income (loss) 18,680,000 (26,283,000)
Other, net 7,681,000  
Income tax expense (benefit) 5,239,000 22,039,000
Additions to crude oil and natural gas properties and equipment - accrual 2,515,000 9,421,000
Operating Segments [Member] | Equatorial Guinea Segment [Member]    
Segment Reporting Information [Line Items]    
Operating income (loss) (132,000) (125,000)
Other, net (2,000)  
Income tax expense (benefit) 1,000  
Corporate and Other [Member]    
Segment Reporting Information [Line Items]    
Depreciation, depletion and amortization 27,000 31,000
Operating income (loss) (4,205,000) (275,000)
Derivative instruments gain (loss), net (5,954,000) 7,339,000
Other, net (3,099,000)  
Income tax expense (benefit) $ (2,154,000) $ 11,439,000