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RELATED PARTY TRANSACTIONS (Details) - USD ($) $ in Thousands	12 Months Ended
	Sep. 30, 2018	Sep. 30, 2017	Sep. 30, 2016	Dec. 11, 2015
ADVISOR'S COMPENSATION AND RELATED PARTY TRANSACTIONS
Related party expense	$ 0	$ 0	$ 2,221
General and administrative to related party	497	346	157
Amended and restated advisory agreement, as amended in January 2012 \| Real estate investment trust management corporation
ADVISOR'S COMPENSATION AND RELATED PARTY TRANSACTIONS
Related party expense	0	0	693
Director \| Advisory services
ADVISOR'S COMPENSATION AND RELATED PARTY TRANSACTIONS
Related party expense	1,253	1,193
Majestic Property Management Corp. \| Real property management, real estate brokerage and construction supervision services
ADVISOR'S COMPENSATION AND RELATED PARTY TRANSACTIONS
Related party expense	33	32	34
Gould Investors L.P. \| Shared services agreement
ADVISOR'S COMPENSATION AND RELATED PARTY TRANSACTIONS
General and administrative to related party	823	723	549
Affiliated entity \| Management fee
ADVISOR'S COMPENSATION AND RELATED PARTY TRANSACTIONS
Related party expense	3,670	2,834	1,919
Affiliated entity \| Payment of acquisition fee
ADVISOR'S COMPENSATION AND RELATED PARTY TRANSACTIONS
Related party expense	2,043	2,571	2,221
Affiliated entity \| Insurance reimbursement
ADVISOR'S COMPENSATION AND RELATED PARTY TRANSACTIONS
Related party expense	$ 26	$ 24	41
Unsecured short term borrowing from Gould Investors L.P. \| Other notes payable \| Affiliated entity
ADVISOR'S COMPENSATION AND RELATED PARTY TRANSACTIONS
Debt face amount				$ 8,000
Interest rate (as a percent)				5.24%
Interest expense, related party			$ 86