CONDENSED CONSOLIDATED STATEMENTS OF COMPREHENSIVE LOSS (USD $) In Thousands, unless otherwise specified	3 Months Ended	6 Months Ended
Mar. 31, 2015	Mar. 31, 2014	Mar. 31, 2015	Mar. 31, 2014
Statement of Comprehensive Income [Abstract]
Net loss	$ (1,873)us-gaap_ProfitLoss	$ (324)us-gaap_ProfitLoss	$ (2,156)us-gaap_ProfitLoss	$ (1,324)us-gaap_ProfitLoss
Other comprehensive loss:
Foreign currency translation adjustments, net of taxes of $0	(772)	(921)	(1,179)	(1,701)
Retirement plans - amortization of accumulated other comprehensive loss into net periodic benefit cost, net of taxes of $0	27	8	53	16
Total other comprehensive loss	(745)	(913)	(1,126)	(1,685)
Total comprehensive loss	(2,618)	(1,237)	(3,282)	(3,009)
Less: Comprehensive income (loss) attributable to non-controlling interests	144	(39)	328	(50)
Comprehensive loss attributable to Barnwell Industries, Inc.	$ (2,762)us-gaap_ComprehensiveIncomeNetOfTax	$ (1,198)us-gaap_ComprehensiveIncomeNetOfTax	$ (3,610)us-gaap_ComprehensiveIncomeNetOfTax	$ (2,959)us-gaap_ComprehensiveIncomeNetOfTax

Amount after tax of increase (decrease) in equity from transactions and other events and circumstances from net income and other comprehensive income, attributable to parent entity. Excludes changes in equity resulting from investments by owners and distributions to owners.

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Amount after tax of increase (decrease) in equity from transactions and other events and circumstances from net income (loss) and other comprehensive income (loss), attributable to noncontrolling interests. Excludes changes in equity resulting from investments by owners and distributions to owners.

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Amount after tax and reclassification adjustments of gain (loss) on foreign currency translation adjustments, foreign currency transactions designated and effective as economic hedges of a net investment in a foreign entity and intra-entity foreign currency transactions that are of a long-term-investment nature.

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Amount after tax and reclassification adjustments of other comprehensive income (loss).

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Amount after tax and reclassification adjustments, of (increase) decrease in accumulated other comprehensive (income) loss related to pension and other postretirement defined benefit plans.

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The consolidated profit or loss for the period, net of income taxes, including the portion attributable to the noncontrolling interest.

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