INFORMATION RELATING TO THE CONDENSED CONSOLIDATED STATEMENTS OF CASH FLOWS (Details) - USD ($) $ in Thousands	6 Months Ended
Mar. 31, 2017	Mar. 31, 2016
Supplemental disclosure of cash flow information:
Interest	$ 5	$ 64
Income taxes refunded, net	(180)	0
Supplemental disclosure of non-cash investing and financing activities:
Release of restricted cash held in escrow for tax installment	0	2,000
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	(183)	(69)
Increase (decrease) in capital expenditure accruals related to oil and natural gas asset retirement obligations	$ (62)	$ 123

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

No definition available.

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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

No definition available.

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- Definition

The amount of cash paid during the current period to foreign, federal, state, and local authorities as taxes on income, net of any cash received during the current period as refunds for the overpayment of taxes.

+ 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=66902209&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

Reference 2: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 230
-SubTopic 10
-Section 45
-Paragraph 25
-Subparagraph (e)
-URI http://asc.fasb.org/extlink&oid=66902209&loc=d3e3536-108585

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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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