Amount of asset retirement obligations divested during the period.

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Percent Difference in Capitalized Costs Divided by Proved Reserves if the Gain is Recorded as Opposed to being Credited against the full-cost pool

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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.

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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 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.

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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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The amount of net income (loss) for the period per each share of common stock or unit outstanding during the reporting period.

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Amount of gain (loss) on sale or disposal of oil and gas property or timber property.

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Carrying amount due within one year of the balance sheet date (or one operating cycle, if longer) from tax authorities as of the balance sheet date representing refunds of overpayments or recoveries based on agreed-upon resolutions of disputes.

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OIL AND NATURAL GAS PROPERTIES AND ASSET RETIREMENT OBLIGATION (Details) - USD ($) $ / shares in Units, $ in Thousands	1 Months Ended		3 Months Ended		6 Months Ended
	Feb. 28, 2018	Oct. 31, 2017	Mar. 31, 2018	Mar. 31, 2017	Mar. 31, 2018	Mar. 31, 2017	Sep. 30, 2017
Asset Retirement Obligation, Roll Forward Analysis [Roll Forward]
Asset retirement obligation as of beginning of period		$ 6,863			$ 6,863
Liabilities associated with properties sold					(1,752)
Revision of estimated obligation					47
Accretion expense					136	$ 213
Payments					(538)
Foreign currency translation adjustment					(121)
Asset retirement obligation as of end of period			$ 4,635		4,635
Less current portion			(1,223)		(1,223)		$ (1,231)
Asset retirement obligation, long-term			3,412		3,412		5,632
Proceeds from the sale of oil and natural gas properties					763	0
Income taxes receivable			2,208		2,208		$ 1,145
Gain on sale of oil and natural gas properties			2,250	$ 0	2,250	0
Total revenues			1,975	3,029	3,831	7,319
Net earnings (loss)			663	(642)	(371)	1,560
Net loss attributable to Barnwell Industries, Inc. stockholders			$ 679	$ (615)	$ (338)	$ 1,026
Net loss per common share attributable to Barnwell Industries, Inc. stockholders (in dollars per share)			$ 0.08	$ (0.07)	$ (0.04)	$ 0.12
Pouce Coupe
Asset Retirement Obligation, Roll Forward Analysis [Roll Forward]
Proceeds from the sale of oil and natural gas properties		$ 72
Income taxes receivable			$ 37		$ 37
Red Earth
Asset Retirement Obligation, Roll Forward Analysis [Roll Forward]
Liabilities associated with properties sold					(1,666)
Proceeds from the sale of oil and natural gas properties	$ 1,360
Income taxes receivable			$ 752		752
Percent Difference in Capitalized Costs Divided by Proved Reserves if the Gain is Recorded as Opposed to being Credited against the full-cost pool	322.00%
Gain on sale of oil and natural gas properties					2,135
Total revenues					3,831	$ 7,319
Net earnings (loss)					(371)	1,560
Net loss attributable to Barnwell Industries, Inc. stockholders					$ (338)	$ 1,026
Net loss per common share attributable to Barnwell Industries, Inc. stockholders (in dollars per share)					$ (0.04)	$ 0.12
Stolberg
Asset Retirement Obligation, Roll Forward Analysis [Roll Forward]
Proceeds from the sale of oil and natural gas properties	$ 120
Gain on sale of oil and natural gas properties					$ 115
Pro Forma \| Red Earth
Asset Retirement Obligation, Roll Forward Analysis [Roll Forward]
Total revenues					3,439	$ 6,794
Net earnings (loss)					(2,223)	1,450
Net loss attributable to Barnwell Industries, Inc. stockholders					$ (2,190)	$ 916
Net loss per common share attributable to Barnwell Industries, Inc. stockholders (in dollars per share)					$ (0.26)	$ 0.11