Annual report pursuant to Section 13 and 15(d)

Selected Quarterly Financial Information (Schedule Of Error Correction) (Details)

v3.10.0.1
Selected Quarterly Financial Information (Schedule Of Error Correction) (Details) - USD ($)
$ / shares in Units, $ in Thousands
Dec. 31, 2018
Sep. 30, 2018
Dec. 31, 2017
Dec. 31, 2016
Dec. 31, 2015
Current assets:          
Cash and cash equivalents $ 33,360 $ 33,715 $ 19,669    
Restricted cash 804 1,025 842    
Receivables:          
Trade 11,907   3,556    
Accounts with joint venture owners, net of allowance of $0.5 million for both years presented 949 931 3,395    
Other 1,398 408 100    
Crude oil inventory 785 2,232 3,263    
Prepayments and other 6,301 3,058 2,791    
Current assets - discontinued operations 3,290 3,222 2,836    
Total current assets 58,794 44,591 36,452    
Oil and natural gas properties and equipment - successful efforts method:          
Proved properties   409,611      
Unproved properties 23,771 23,771 10,000    
Equipment and other 9,552 8,821 9,432    
Gross oil and natural gas properties, equipment and other 443,329 442,203 409,367    
Accumulated depreciation, depletion, amortization and impairment (390,605) (388,660) (386,146)    
Net oil and natural gas properties, equipment and other 52,724 53,543 23,221    
Other noncurrent assets:          
Restricted cash 920 918 967    
Value added tax and other receivables, net of allowance of $2.0 million and $6.5 million, respectively 2,226 2,306 6,925    
Deferred tax assets 40,077 50,195 1,260    
Abandonment funding 11,571 10,808 10,808    
Total assets 166,312 162,361 79,633    
Current liabilities:          
Accounts payable 8,083 7,219 11,584    
Accounts with joint venture owners 304 5,496      
Accrued liabilities and other 14,138 17,662 12,991    
Foreign taxes payable 3,274 1,775      
Current portion of long term debt     6,666    
Current liabilities - discontinued operations 15,245 15,191 15,347    
Total current liabilities 41,044 47,343 46,588    
Asset retirement obligations 14,816 14,459 20,163    
Other long-term liabilities 625 1,264 284    
Long term debt, excluding current portion, net     2,309    
Total liabilities 56,485 63,066 69,344    
Commitments and contingencies    
Shareholders’ equity:          
Preferred stock, none issued, 500,000 shares authorized, $25 par value      
Common stock, $0.10 par value; 100,000,000 shares authorized, 67,167,994 and 66,443,971 shares issued, 59,595,742 and 58,862,876 shares outstanding, respectively 6,717 6,709 6,644    
Additional paid-in capital 72,358 72,229 71,251    
Less treasury stock, 7,572,251 and 7,581,095 shares, respectively, at cost (37,827) (37,798) (37,953)    
Retained earnings (deficit) 68,579 58,155 (29,653)    
Total shareholders' equity 109,827 99,295 10,289 $ (358) $ 26,076
Total liabilities and shareholders' equity 166,312 162,361 79,633    
Allowance for accounts with partners 500   500    
Allowance for value added tax receivable $ 2,000   $ 6,500    
Preferred stock, shares issued 0   0    
Preferred stock, shares authorized 500,000   500,000    
Preferred stock, par value $ 25   $ 25    
Common stock, par value $ 0.10   $ 0.10    
Common stock, shares authorized 100,000,000   100,000,000    
Common stock, shares issued 67,167,994   66,443,971    
Common stock, shares outstanding 59,595,742   58,862,876    
Treasury stock, shares 7,572,251   7,581,095    
Previously Reported [Member]          
Current assets:          
Cash and cash equivalents   33,715      
Restricted cash   1,025      
Receivables:          
Accounts with joint venture owners, net of allowance of $0.5 million for both years presented   931      
Other   408      
Crude oil inventory   2,232      
Prepayments and other   3,058      
Current assets - discontinued operations   3,222      
Total current assets   44,591      
Oil and natural gas properties and equipment - successful efforts method:          
Proved properties   398,072      
Unproved properties   16,698      
Equipment and other   8,821      
Gross oil and natural gas properties, equipment and other   423,591      
Accumulated depreciation, depletion, amortization and impairment   (388,660)      
Net oil and natural gas properties, equipment and other   34,931      
Other noncurrent assets:          
Restricted cash   918      
Value added tax and other receivables, net of allowance of $2.0 million and $6.5 million, respectively   2,306      
Deferred tax assets   68,807      
Abandonment funding   10,808      
Total assets   162,361      
Current liabilities:          
Accounts payable   7,219      
Accounts with joint venture owners   5,496      
Accrued liabilities and other   17,662      
Foreign taxes payable   1,775      
Current liabilities - discontinued operations   15,191      
Total current liabilities   47,343      
Asset retirement obligations   14,459      
Other long-term liabilities   1,264      
Total liabilities   63,066      
Commitments and contingencies        
Shareholders’ equity:          
Common stock, $0.10 par value; 100,000,000 shares authorized, 67,167,994 and 66,443,971 shares issued, 59,595,742 and 58,862,876 shares outstanding, respectively   6,709      
Additional paid-in capital   72,229      
Less treasury stock, 7,572,251 and 7,581,095 shares, respectively, at cost   (37,798)      
Retained earnings (deficit)   58,155      
Total shareholders' equity   99,295      
Total liabilities and shareholders' equity   162,361      
Restatement Adjustment [Member]          
Oil and natural gas properties and equipment - successful efforts method:          
Proved properties   11,539      
Unproved properties   7,073      
Gross oil and natural gas properties, equipment and other   18,612      
Net oil and natural gas properties, equipment and other   18,612      
Other noncurrent assets:          
Deferred tax assets   (18,612)      
Current liabilities:          
Commitments and contingencies