CONDENSED CONSOLIDATED STATEMENTS OF COMPREHENSIVE LOSS (Unaudited) - USD ($) $ in Thousands	3 Months Ended	9 Months Ended
Jun. 30, 2026	Jun. 30, 2025	Jun. 30, 2026	Jun. 30, 2025
Statement of Comprehensive Income [Abstract]
Net loss	$ (403)	$ (1,553)	$ (2,931)	$ (4,679)
Other comprehensive income (loss):
Foreign currency translation adjustments, net of taxes of $0	40	(37)	52	53
Total other comprehensive income (loss)	40	(37)	52	53
Total comprehensive loss	(363)	(1,590)	(2,879)	(4,626)
Less: Comprehensive (income) loss attributable to non-controlling interests	(37)	3	(85)	5
Comprehensive loss attributable to Barnwell Industries, Inc.	$ (400)	$ (1,587)	$ (2,964)	$ (4,621)

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.

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 other comprehensive income (loss).

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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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