PROPERTY AND EQUIPMENT AND ASSET RETIREMENT OBLIGATION (Details) - USD ($) $ in Thousands	12 Months Ended
Sep. 30, 2017	Sep. 30, 2016
Property and equipment
Gross Property and Equipment	$ 79,231	$ 76,868
Accumulated Depletion, Depreciation, and Amortization	(73,862)	(69,966)
Net Property and Equipment	5,369	6,902
Change in the asset retirement obligation
Balance at the beginning of the year	7,194	6,936
Obligations incurred on new wells drilled or acquired	34	167
Liabilities associated with properties sold	(406)	0
Revision of estimated obligation	154	(68)
Accretion expense	433	464
Payments	(833)	(459)
Foreign currency translation adjustment	287	154
Balance at the end of the year	6,863	7,194
Less current portion	(1,231)	(1,017)
Asset retirement obligation, long-term	5,632	6,177
Land
Property and equipment
Gross Property and Equipment	365	365
Net Property and Equipment	365	365
Oil and natural gas properties
Property and equipment
Gross Property and Equipment	68,708	66,265
Accumulated Depletion, Depreciation, and Amortization	(64,915)	(61,060)
Net Property and Equipment	3,793	5,205
Drilling rigs and equipment
Property and equipment
Gross Property and Equipment	6,577	6,379
Accumulated Depletion, Depreciation, and Amortization	(5,992)	(5,770)
Net Property and Equipment	$ 585	$ 609
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	$ 857	$ 857
Accumulated Depletion, Depreciation, and Amortization	(295)	(274)
Net Property and Equipment	562	583
Other property and equipment
Property and equipment
Gross Property and Equipment	2,724	3,002
Accumulated Depletion, Depreciation, and Amortization	(2,660)	(2,862)
Net Property and Equipment	$ 64	$ 140
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

Amount of asset retirement obligations divested during the period.

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Amount of accumulated depreciation, depletion and amortization for physical assets used in the normal conduct of business to produce goods and services.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 360
-SubTopic 10
-Section 50
-Paragraph 1
-Subparagraph (c)
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-Name Accounting Standards Codification
-Topic 210
-SubTopic 10
-Section S99
-Paragraph 1
-Subparagraph (SX 210.5-02.14)
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The carrying amount of a liability for an asset retirement obligation. An asset retirement obligation is a legal obligation associated with the disposal or retirement of a tangible long-lived asset that results from the acquisition, construction or development, or the normal operations of a long-lived asset, except for certain obligations of lessees.

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Amount of accretion expense recognized during the period that is associated with an asset retirement obligation. Accretion expense measures and incorporates changes due to the passage of time into the carrying amount of the liability.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 410
-SubTopic 20
-Section 50
-Paragraph 1
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Current portion of the carrying amount of a liability for an asset retirement obligation. An asset retirement obligation is a legal obligation associated with the disposal or retirement of a tangible long-lived asset that results from the acquisition, construction or development, or the normal operations of a long-lived asset, except for certain obligations of lessees.

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Amount of foreign currency translation gain (loss) which decreases (increases) asset retirement obligations.

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Amount of asset retirement obligations incurred during the period.

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Amount of asset retirement obligations settled, or otherwise disposed of, during the period. This may include asset retirement obligations transferred to third parties associated with the sale of a long-lived asset.

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Amount of increase (decrease) in the asset retirement obligation from changes in the amount or timing of the estimated cash flows associated with the settlement of the obligation.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
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A roll forward is a reconciliation of a concept from the beginning of a period to the end of a period.

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Noncurrent portion of the carrying amount of a liability for an asset retirement obligation. An asset retirement obligation is a legal obligation associated with the disposal or retirement of a tangible long-lived asset that results from the acquisition, construction or development, or the normal operations of a long-lived asset, except for certain obligations of lessees.

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Amount before accumulated depreciation, depletion and amortization of physical assets used in the normal conduct of business and not intended for resale. Examples include, but are not limited to, land, buildings, machinery and equipment, office equipment, and furniture and fixtures.

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Reference 1: http://www.xbrl.org/2003/role/presentationRef
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Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table.

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Amount after accumulated depreciation, depletion and amortization of physical assets used in the normal conduct of business to produce goods and services and not intended for resale. Examples include, but are not limited to, land, buildings, machinery and equipment, office equipment, and furniture and fixtures.

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Useful life of long lived, physical assets used in the normal conduct of business and not intended for resale, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days. Examples include, but not limited to, land, buildings, machinery and equipment, office equipment, furniture and fixtures, and computer equipment.

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