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Carrying value as of the balance sheet date, including the current and noncurrent portions, of collateralized debt obligations (with maturities initially due after one year or beyond the operating cycle, if longer). Such obligations include mortgage loans, chattel loans, and any other borrowings secured by assets of the borrower.

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INVESTMENT IN UNCONSOLIDATED JOINT VENTURES (Hamilton Bay Apts and Sales) (Details)	1 Months Ended	6 Months Ended
	Feb. 28, 2007 USD ($) item	Jun. 30, 2019 USD ($) property	Dec. 31, 2018 USD ($)	Jun. 30, 2018 USD ($) property	Mar. 01, 2017 USD ($)	Oct. 03, 2005 USD ($) item
INVESTMENT IN UNCONSOLIDATED JOINT VENTURES
Investments in joint venture		$ 1,610,362	$ 1,985,680	$ 2,298,596
Number of units \| property				913
Number of units retained for long-term investment \| property				(690)
Outstanding amount of mortgage		252,012,154	$ 252,370,843
Unsold units \| property				8
Hamilton Bay Apts
INVESTMENT IN UNCONSOLIDATED JOINT VENTURES
Investments in joint venture		$ 10,328		$ 513,544		$ 2,500,000
Ownership interest (as a percent)				50.00%		50.00%
Number of units		48		48		168
Number of units sold \| item						120
Number of units retained for long-term investment \| item						48
Interest rate (as a percent)	5.57%
Period for which the entity is required to make interest only payments	5 years
Amortization period of debt	30 years
Outstanding amount of mortgage					$ 2,222,000
Gain on the sale of real estate		$ 433,000
Unsold units \| property				4
Purchase price of investments						$ 30,875,000
Borrowings	$ 4,750,000
Residential buildings
INVESTMENT IN UNCONSOLIDATED JOINT VENTURES
Number of units \| property				910
Residential buildings \| Hamilton Bay Apts
INVESTMENT IN UNCONSOLIDATED JOINT VENTURES
Number of units	48	48		48
Mortgages payable \| Minimum
INVESTMENT IN UNCONSOLIDATED JOINT VENTURES
Interest rate (as a percent)		3.76%
Mortgages payable \| Maximum
INVESTMENT IN UNCONSOLIDATED JOINT VENTURES
Interest rate (as a percent)		5.81%