Quarterly report pursuant to Section 13 or 15(d)

Segment Information (Segment Activity) (Details)

v3.19.1
Segment Information (Segment Activity) (Details) - USD ($)
$ in Thousands
3 Months Ended
Mar. 31, 2019
Mar. 31, 2018
Segment Reporting Information [Line Items]    
Revenues-oil and natural gas sales $ 19,765 $ 27,645
Depreciation, depletion and amortization 1,553 1,124
Recorded allowance (29) (56)
Operating income (loss) 5,546 13,038
Derivative instruments loss, net (1,912)  
Other, net (238) 69
Interest income 187 (354)
Income tax expense 2,753 4,042
Additions to oil and natural gas properties and equipment - accrual 685 427
Operating Segments | Gabon Segment [Member]    
Segment Reporting Information [Line Items]    
Revenues-oil and natural gas sales 19,765 27,643
Depreciation, depletion and amortization 1,479 1,059
Recorded allowance (29) (56)
Operating income (loss) 9,530 15,697
Other, net (172) 69
Interest income 1 (354)
Income tax expense 2,491 4,042
Additions to oil and natural gas properties and equipment - accrual 681 428
Operating Segments | Equatorial Guinea Segment [Member]    
Segment Reporting Information [Line Items]    
Operating income (loss) (186) (30)
Other, net (2) 3
Income tax expense 10  
Additions to oil and natural gas properties and equipment - accrual (187)  
Corporate and Other    
Segment Reporting Information [Line Items]    
Revenues-oil and natural gas sales   2
Depreciation, depletion and amortization 74 65
Operating income (loss) (3,798) (2,629)
Derivative instruments loss, net (1,912)  
Other, net (64) (3)
Interest income 186  
Income tax expense 252  
Additions to oil and natural gas properties and equipment - accrual $ 191 $ (1)