Annual report pursuant to Section 13 and 15(d)

Subsequent Events (Details)

v3.3.0.814
Subsequent Events (Details)
AUD / shares in Units, $ / shares in Units, £ in Thousands, AUD in Millions
 1 Months Ended 12 Months Ended
Oct. 09, 2015
AUD
shares
Sep. 30, 2015
shares
Jul. 01, 2015
shares
Aug. 31, 2015
GBP (£)
Jul. 31, 2015
USD ($)
shares
Jun. 30, 2015
USD ($)
$ / shares
shares
Jun. 30, 2014
$ / shares
shares
Jul. 10, 2015
$ / shares
shares
Jul. 09, 2015
shares
Jun. 30, 2015
AUD / shares
Jun. 30, 2013
shares
May. 10, 2013
$ / shares
Subsequent Event [Line Items]                        
Common stock, issued (in shares)           6,917,027 6,875,605          
Treasury stock, (in shares)           1,209,389 1,178,139       1,176,772  
Net shares repurchased for employee tax costs upon vesting of restricted stock (in shares)           5,981 1,367          
Number of stock options expired           12,499 0          
Shares owned in investment           6,917,027 6,875,605          
Current share price (usd per share) | $ / shares           $ 0.01 $ 0.01          
Central Petroleum                        
Subsequent Event [Line Items]                        
Current share price (usd per share) | AUD / shares                   AUD 0.155    
Foreign exchange rate           0.72            
Potential liquidity | $           $ 3,100,000            
Series A Preferred Stock                        
Subsequent Event [Line Items]                        
Price per share (in dollars per share) | $ / shares                       $ 1.22149381
Subsequent Event                        
Subsequent Event [Line Items]                        
Common stock, issued (in shares)               6,911,921 55,313,647      
Treasury stock, (in shares)               1,209,389 9,675,114      
Number of stock options expired   33,333                    
Shares, including forfeited shares, available for future issuance 202,786                      
Subsequent Event | NT/P82 Seismic Survey                        
Subsequent Event [Line Items]                        
Cash payment for first initial stage | $         $ 20,000              
Cash payment for second initial stage | $         80,000              
Success fee minimum amount | $         $ 250,000              
Success fee maximum amount (percentage)         5.00%              
Subsequent Event | Celtique Litigation                        
Subsequent Event [Line Items]                        
License fees paid | £       £ 50                
Subsequent Event | Central Petroleum                        
Subsequent Event [Line Items]                        
Investment owned, number of shares 27,400,000                      
Subsequent Event | Amadeus Basin | Central Petroleum                        
Subsequent Event [Line Items]                        
Investment owned, number of shares         39,500,000              
Proceeds from sale of shares | AUD AUD 1.3                      
Subsequent Event | Restricted Stock Units (RSUs)                        
Subsequent Event [Line Items]                        
Shares vested (in shares)     12,500                  
Net shares repurchased for employee tax costs upon vesting of restricted stock (in shares)     2,822                  
Subsequent Event | Series A Preferred Stock                        
Subsequent Event [Line Items]                        
Adjusted conversion price (usd per share) | $ / shares               $ 9.77586545