CONSOLIDATED STATEMENTS OF OPERATIONS (USD $)	12 Months Ended
	Sep. 30, 2011	Sep. 30, 2010
Revenues:
Oil and natural gas	$ 28,804,000	$ 27,556,000
Contract drilling	3,855,000	6,517,000
Sale of interest in leasehold land, net	1,245,000	3,347,000
Sale of development rights, net	2,497,000	2,497,000
Gas processing and other	2,059,000	1,955,000
Total revenues	38,460,000	41,872,000
Costs and expenses:
Oil and natural gas operating	11,404,000	10,203,000
Contract drilling operating	3,882,000	5,600,000
General and administrative	9,025,000	8,331,000
Depletion, depreciation, and amortization	10,127,000	9,302,000
Reduction of carrying value of assets	1,228,000	2,149,000
Interest expense	1,088,000	1,225,000
Total costs and expenses	36,754,000	36,810,000
Earnings before income taxes	1,706,000	5,062,000
Income tax provision	1,501,000	765,000
Net earnings	205,000	4,297,000
Less: Net earnings attributable to non-controlling interests	314,000	457,000
Net (loss) earnings attributable to Barnwell Industries, Inc.	$ (109,000)	$ 3,840,000
Basic net (loss) earnings per common share attributable to Barnwell Industries, Inc. stockholders (in dollars per share)	$ (0.01)	$ 0.46
Diluted net (loss) earnings per common share attributable to Barnwell Industries, Inc. stockholders (in dollars per share)	$ (0.01)	$ 0.46
Weighted-average number of common shares outstanding:
Basic (in shares)	8,277,160	8,273,848
Diluted (in shares)	8,277,160	8,273,848