Amount of 50% of Increment II post- threshold distributions received by KD

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Recognition of the difference between amount at which an investment accounted for under the equity method of accounting is carried (reported) on the balance sheet and amount of underlying equity in net assets the reporting Entity has in the investee.

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The cumulative cash distributions from Kukio Resort Land Development Partnerships (to all partners), made to date.

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The cumulative cash distributions from Kukio Resort Land Development Partnerships, threshold, after which BHP receives a preferred return from KKM, up to $1M.

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INVESTMENTS - INVESTMENT IN KUKIO RESORT LAND DEVELOPMENT PARTNERSHIP (Details) $ in Thousands		1 Months Ended	12 Months Ended
	Nov. 27, 2013 USD ($) partnership	Jun. 30, 2018 USD ($)	Sep. 30, 2019 USD ($)	Sep. 30, 2018 USD ($)	Mar. 07, 2019
Investment Holdings [Line Items]
Equity in (loss) income of affiliates			$ (276)	$ 223
Investments in land development partnerships
Investment Holdings [Line Items]
Number of limited liability limited partnerships formed \| partnership	2
Cash distribution from equity method investment			314	735
Cumulative cash distributions from Kukio Resort land development partnerships, made to date			45,000
Equity in (loss) income of affiliates			(276)	223
Basis difference between the carrying amount and underlying equity			296
Basis difference adjustment			$ 18	8
KD Kukio Resorts LLLP \| Investments in land development partnerships
Investment Holdings [Line Items]
Ownership interest acquired	19.60%
Indirectly Acquired Interest \| Investments in land development partnerships
Investment Holdings [Line Items]
Aggregate cost	$ 5,140
KD Acquisition, LLLP \| Investments in land development partnerships
Investment Holdings [Line Items]
Ownership interest acquired			19.60%
KD Maniniowali, LLLP \| Investments in land development partnerships
Investment Holdings [Line Items]
Ownership interest acquired	19.60%
KKM Makai LLLP \| Investments in land development partnerships
Investment Holdings [Line Items]
Ownership interest acquired	34.45%
KD Kaupulehu, LLLP \| Investments in land development partnerships
Investment Holdings [Line Items]
Ownership interest acquired	19.60%
KD Kaupulehu, LLLP \| KD Acquisition II, LP \| Investments in land development partnerships
Investment Holdings [Line Items]
Ownership interest acquired					55.00%
Kaupulehu Developments \| KD Kaupulehu LLLP Increment II
Investment Holdings [Line Items]
50% of Increment II distributions received		$ 1,000
Replay \| KD Acquisition II, LP \| Investments in land development partnerships
Investment Holdings [Line Items]
Ownership interest acquired					45.00%
Barnwell Industries Inc \| KD Acquisition II, LP \| Investments in land development partnerships
Investment Holdings [Line Items]
Ownership interest acquired			10.80%
Barnwell Hawaiian Properties, Inc. \| KKM Makai LLLP \| Investments in land development partnerships
Investment Holdings [Line Items]
Preferred return to be received as a percentage from KKM	100.00%
Non-controlling Interests \| Investments in land development partnerships
Investment Holdings [Line Items]
Cash distribution from equity method investment			$ 38	$ 89
Minimum \| Investments in land development partnerships
Investment Holdings [Line Items]
Cumulative cash distributions from Kukio Resort Land Development Partnerships, threshold	$ 45,000
Maximum \| Barnwell Hawaiian Properties, Inc. \| KKM Makai LLLP \| Investments in land development partnerships
Investment Holdings [Line Items]
Preferred return, amount, from KKM	$ 1,000