INFORMATION RELATING TO THE CONDENSED CONSOLIDATED STATEMENTS OF CASH FLOWS (Details) - USD ($) $ in Thousands	6 Months Ended
Mar. 31, 2016	Mar. 31, 2015
Supplemental disclosure of cash flow information:
Interest	$ 64	$ 164
Supplemental disclosure of non-cash investing and financing activities:
Note receivable for sale of investment	0	907
Release of restricted escrow cash for tax installment	2,000	0
Oil and natural gas
Supplemental disclosures of cash flow information:
Increase (Decrease) in capital expenditure accruals related to oil and natural gas exploration and development	(69)	295
Increase (Decrease) in capital expenditure accruals related to oil and natural gas asset retirement obligations	$ 123	$ 938

Amount of cash released from restricted escrow account for income tax installment payment related to property sale.

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- Definition

The increase (decrease) during the reporting period in the capital expenditure accruals related to oil and natural gas exploration and development.

+ References

No definition available.

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- References

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- Definition

The increase (decrease) during the reporting period in the carrying amount of asset retirement obligations.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 230
-SubTopic 10
-Section 45
-Paragraph 28
-Subparagraph (a)
-URI http://asc.fasb.org/extlink&oid=56944662&loc=d3e3602-108585

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- Definition

The amount of cash paid for interest during the period.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 230
-SubTopic 10
-Section 50
-Paragraph 2
-URI http://asc.fasb.org/extlink&oid=6367179&loc=d3e4297-108586

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-Publisher FASB
-Name Accounting Standards Codification
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-Section 45
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- Definition

The fair value of notes issued in noncash investing and financing activities.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 230
-SubTopic 10
-Section 50
-Paragraph 5
-URI http://asc.fasb.org/extlink&oid=6367179&loc=d3e4332-108586

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-Publisher FASB
-Name Accounting Standards Codification
-Topic 230
-SubTopic 10
-Section 50
-Paragraph 3
-URI http://asc.fasb.org/extlink&oid=6367179&loc=d3e4304-108586

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-Publisher FASB
-Name Accounting Standards Codification
-Topic 230
-SubTopic 10
-Section 50
-Paragraph 4
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- Definition

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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