(LOSS) EARNINGS PER COMMON SHARE (Details) - USD ($) $ / shares in Units, $ in Thousands	12 Months Ended
	Sep. 30, 2023	Sep. 30, 2022
Net (Loss) Earnings (Numerator)
Basic	$ (961)	$ 5,513
Effect of dilutive securities - common stock options and restricted stock units	0	0
Diluted	$ (961)	$ 5,513
Shares (Denominator)
Basic (in shares)	9,969,856	9,732,936
Effect of dilutive securities-common stock options and restricted stock units (in shares)	0	0
Diluted (in shares)	9,969,856	9,732,936
Per-Share Amount
Basic net (loss) earnings per common share attributable to Barnwell Industries, Inc. stockholders (in dollars per share)	$ (0.10)	$ 0.57
Diluted net (loss) earnings per common share attributable to Barnwell Industries, Inc. stockholders (in dollars per share)	$ (0.10)	$ 0.57
Options
Antidilutive shares of common stock excluded from the computation of diluted shares
Antidilutive shares excluded from computation of (loss) earnings per share (in shares)	546,781	615,000
Restricted Stock Units (RSUs)
Antidilutive shares of common stock excluded from the computation of diluted shares
Antidilutive shares excluded from computation of (loss) earnings per share (in shares)	18,605