CONDENSED CONSOLIDATED STATEMENTS OF COMPREHENSIVE INCOME (LOSS) (Unaudited) - USD ($) $ in Thousands	3 Months Ended	6 Months Ended
Mar. 31, 2018	Mar. 31, 2017	Mar. 31, 2018	Mar. 31, 2017
Statement of Comprehensive Income [Abstract]
Net earnings (loss)	$ 663	$ (642)	$ (371)	$ 1,560
Other comprehensive (loss) income:
Foreign currency translation adjustments, net of taxes of $0	(181)	22	(187)	(48)
Retirement plans - amortization of accumulated other comprehensive loss into net periodic benefit cost, net of taxes of $0	39	96	63	193
Total other comprehensive (loss) income	(142)	118	(124)	145
Total comprehensive earnings (loss)	521	(524)	(495)	1,705
Less: Comprehensive (loss) earnings attributable to non-controlling interests	(16)	(27)	(33)	534
Comprehensive earnings (loss) attributable to Barnwell Industries, Inc.	$ 537	$ (497)	$ (462)	$ 1,171

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 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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