SUMMARY OF SELECTED QUARTERLY FINANCIAL DATA (UNAUDITED)	12 Months Ended
Sep. 30, 2020
Quarterly Financial Information Disclosure [Abstract]
SUMMARY OF SELECTED QUARTERLY FINANCIAL DATA (UNAUDITED)	SUMMARY OF SELECTED QUARTERLY FINANCIAL DATA (UNAUDITED) Disclosure is not required as Barnwell qualifies as a smaller reporting company.

The entire disclosure for quarterly financial data. Includes, but is not limited to, tabular presentation of financial information for fiscal quarters, effect of year-end adjustments, and an explanation of matters or transactions that affect comparability of the information.

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 270
-URI http://asc.fasb.org/topic&trid=2126967

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