PROPERTY AND EQUIPMENT AND ASSET RETIREMENT OBLIGATION (Details) (USD $)	12 Months Ended
	Sep. 30, 2012	Sep. 30, 2011
Property and equipment
Gross property and equipment	$ 256,153,000	$ 239,036,000
Accumulated depletion, depreciation, and amortization	(207,529,000)	(184,417,000)
Net property and equipment	48,624,000	54,619,000
Reduction of carrying value of assets	6,647,000	1,228,000
Change in the asset retirement obligation
Balance at the beginning of the year	4,921,000	4,869,000
Obligations incurred on new wells drilled	68,000	123,000
Revision of estimated obligation	320,000	(330,000)
Accretion expense	363,000	341,000
Payments	(324,000)	(36,000)
Foreign currency translation adjustment	281,000	(46,000)
Balance at the end of the year	5,629,000	4,921,000
Land
Property and equipment
Gross property and equipment	863,000	863,000
Net property and equipment	863,000	863,000
Oil and natural gas properties
Property and equipment
Gross property and equipment	242,433,000	224,852,000
Accumulated depletion, depreciation, and amortization	(198,768,000)	(175,715,000)
Net property and equipment	43,665,000	49,137,000
Reduction of carrying value of assets	2,551,000
Drilling rigs and equipment
Property and equipment
Gross property and equipment	6,752,000	7,020,000
Accumulated depletion, depreciation, and amortization	(5,152,000)	(4,988,000)
Net property and equipment	1,600,000	2,032,000
Drilling rigs and equipment | Minimum
Property and equipment
Estimated useful lives	3 years	3 years
Drilling rigs and equipment | Maximum
Property and equipment
Estimated useful lives	10 years	10 years
Offices
Property and equipment
Estimated useful lives	40 years	40 years
Gross property and equipment	2,420,000	2,420,000
Accumulated depletion, depreciation, and amortization	(264,000)	(203,000)
Net property and equipment	2,156,000	2,217,000
Other property and equipment
Property and equipment
Gross property and equipment	3,685,000	3,881,000
Accumulated depletion, depreciation, and amortization	(3,345,000)	(3,511,000)
Net property and equipment	$ 340,000	$ 370,000
Other property and equipment | Minimum
Property and equipment
Estimated useful lives	3 years	3 years
Other property and equipment | Maximum
Property and equipment
Estimated useful lives	17 years	17 years