Quarterly report pursuant to Section 13 or 15(d)

Segment Information (Segment Activity) (Details)

v3.7.0.1
Segment Information (Segment Activity) (Details) - USD ($)
$ in Thousands
 3 Months Ended 6 Months Ended
Jun. 30, 2017
Jun. 30, 2016
Mar. 31, 2016
Jun. 30, 2017
Jun. 30, 2016
Dec. 31, 2016
Segment Reporting Information [Line Items]            
Revenues-oil and natural gas sales $ 20,425 $ 18,847   $ 41,691 $ 29,823  
Depreciation, depletion and amortization 1,970 1,942   3,839 4,180  
Impairment of proved properties   0 $ 0      
Bad debt expense and other 183 171   281 514  
Other operating expense   754     9,635  
Operating income (loss) 5,587 4,615   13,735 (8,900)  
Interest incoome (expense), net (378) (1,470)   (781) (1,958)  
Income tax expense 3,096 3,001   6,290 4,686  
Additions to properties and equipment 625 (2,353)   814 (2,353)  
Total assets 79,143     79,143   $ 81,032
Continuing Operations [Member]            
Segment Reporting Information [Line Items]            
Total assets 76,565     76,565   78,893
Operating Segments [Member] | Gabon [Member]            
Segment Reporting Information [Line Items]            
Revenues-oil and natural gas sales 20,415 18,764   41,661 29,672  
Depreciation, depletion and amortization 1,902 1,833   3,711 3,976  
Bad debt expense and other 183 171   281 514  
Other operating expense   754     9,635  
Operating income (loss) 8,090 8,424   19,050 (3,532)  
Interest incoome (expense), net (378) (1,468)   (781) (1,956)  
Income tax expense 3,096 3,001   6,290 4,686  
Additions to properties and equipment 625 (2,493)   814 (2,493)  
Operating Segments [Member] | Gabon [Member] | Continuing Operations [Member]            
Segment Reporting Information [Line Items]            
Total assets 62,481     62,481   64,478
Operating Segments [Member] | Equatorial Guinea [Member]            
Segment Reporting Information [Line Items]            
Operating income (loss) (15) (87)   (53) (135)  
Operating Segments [Member] | Equatorial Guinea [Member] | Continuing Operations [Member]            
Segment Reporting Information [Line Items]            
Total assets 10,108     10,108   10,122
Operating Segments [Member] | U.S. [Member]            
Segment Reporting Information [Line Items]            
Revenues-oil and natural gas sales 10 83   30 151  
Depreciation, depletion and amortization 0 42   1 63  
Operating income (loss) 339     346 (3)  
Additions to properties and equipment   140     140  
Operating Segments [Member] | U.S. [Member] | Continuing Operations [Member]            
Segment Reporting Information [Line Items]            
Total assets 108     108   382
Corporate And Other [Member]            
Segment Reporting Information [Line Items]            
Depreciation, depletion and amortization 68 67   127 141  
Operating income (loss) (2,827) (3,722)   (5,608) (5,230)  
Interest incoome (expense), net   $ (2)     $ (2)  
Corporate And Other [Member] | Continuing Operations [Member]            
Segment Reporting Information [Line Items]            
Total assets $ 3,868     $ 3,868   $ 3,911