Annual report pursuant to Section 13 and 15(d)

Supplemental Oil and Gas Information (Unaudited) - Proved Reserves Quantities (Details)

v3.3.0.814
Supplemental Oil and Gas Information (Unaudited) - Proved Reserves Quantities (Details)
12 Months Ended
Jun. 30, 2015
MBbls
bbl
MMcf
Jun. 30, 2014
well
bbl
MMcf
Proved Developed and Undeveloped Reserves [Abstract]    
Revision of previous estimates | MBbls (3,417,000)  
Removal proved undeveloped reserves from the classification of proved reserves due to uncertainty | MBbls 3,083,000  
Number of wells in drilling program | well   9
Number of wells recently drilled for CO2EOR pilot project | well   5
Oil (in Mbbls)    
Proved Developed and Undeveloped Reserves [Abstract]    
Beginning Balance 5,735,700 7,368,600
Revision of previous estimates (3,417,100) (1,515,000)
Sales of minerals in place   0
Production (79,000) (117,900)
Ending Balance 2,239,600 5,735,700
Proved Developed Reserves (Volume) 2,239,600 2,494,600
Proved Undeveloped Reserves (Volume) 0 3,241,100
Gas (in MMcf)    
Proved Developed and Undeveloped Reserves [Abstract]    
Beginning Balance | MMcf 0 11,400
Revision of previous estimates | MMcf 0 0
Sales of minerals in place | MMcf   (11,400)
Production | MMcf 0 0
Ending Balance | MMcf 0 0
Proved Developed Reserves (Volume) | MMcf 0 0
Proved Undeveloped Reserves (Volume) | MMcf 0 0
United States | Oil (in Mbbls)    
Proved Developed and Undeveloped Reserves [Abstract]    
Beginning Balance 5,735,700 7,368,600
Revision of previous estimates (3,417,100) (1,515,000)
Sales of minerals in place   0
Production (79,000) (117,900)
Ending Balance 2,239,600 5,735,700
Proved Developed Reserves (Volume) 2,239,600 2,494,600
Proved Undeveloped Reserves (Volume) 0 3,241,100
Australia | Gas (in MMcf)    
Proved Developed and Undeveloped Reserves [Abstract]    
Beginning Balance | MMcf 0 11,400
Revision of previous estimates | MMcf 0 0
Sales of minerals in place | MMcf   (11,400)
Production | MMcf 0 0
Ending Balance | MMcf 0 0
Proved Developed Reserves (Volume) | MMcf 0 0
Proved Undeveloped Reserves (Volume) | MMcf 0 0