CONSOLIDATED STATEMENTS OF COMPREHENSIVE (LOSS) INCOME - USD ($) $ in Thousands	12 Months Ended
Sep. 30, 2018	Sep. 30, 2017
Statement of Comprehensive Income [Abstract]
Net (loss) earnings	$ (1,418)	$ 2,314
Other comprehensive income:
Foreign currency translation adjustments, net of taxes of $0	(128)	147
Retirement plans:
Amortization of accumulated other comprehensive loss into net periodic benefit cost, net of taxes of $0	124	326
Net actuarial gains (losses) arising during the period, net of taxes of $0	548	2,389
Total other comprehensive income	544	2,862
Total comprehensive (loss) income	(874)	5,176
Less: Comprehensive income attributable to non-controlling interests	352	1,143
Comprehensive (loss) income attributable to Barnwell Industries, Inc.	$ (1,226)	$ 4,033

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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