Represents the number of units retained for long-term investment.

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- Definition

Represents the number of units sold.

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No definition available.

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- Definition

The number of units under a purchase and sale agreement.

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Represents the number of units unsold by the entity.

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- Definition

Contractual interest rate for funds borrowed, under the debt agreement.

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- Definition

Amount after tax of gain (loss) not previously recognized resulting from the disposal of a discontinued operation.

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This item represents the carrying amount on the entity's balance sheet of its investment in common stock of an equity method investee. This is not an indicator of the fair value of the investment, rather it is the initial cost adjusted for the entity's share of earnings and losses of the investee, adjusted for any distributions (dividends) and other than temporary impairment (OTTI) losses recognized.

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The number of units in a real estate property owned as of the balance sheet date.

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Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table.

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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)	12 Months Ended
	Dec. 31, 2017 USD ($) item	Dec. 31, 2016 USD ($)	Dec. 31, 2015 USD ($) item
INVESTMENT IN UNCONSOLIDATED JOINT VENTURES
Investments in joint venture \| $	$ 7,212,044	$ 8,336,505	$ 7,819,162
Number of units			1,033
Number of units sold			242
Number of units retained for long-term investment			(786)
Outstanding amount of mortgage \| $	$ 233,221,258	$ 212,709,080
Unsold units			5
Hamilton Bay Sales and Hamilton Bay Apartments
INVESTMENT IN UNCONSOLIDATED JOINT VENTURES
Number of units	19
Number of units under a purchase and sale agreement	6
Hamilton Bay Apts
INVESTMENT IN UNCONSOLIDATED JOINT VENTURES
Number of units sold	1
Gain on the sale of real estate \| $	$ 133,000
Residential buildings
INVESTMENT IN UNCONSOLIDATED JOINT VENTURES
Number of units			1,030
Mortgages payable
INVESTMENT IN UNCONSOLIDATED JOINT VENTURES
Outstanding amount of mortgage \| $	$ 233,221,000
Mortgages payable \| Minimum
INVESTMENT IN UNCONSOLIDATED JOINT VENTURES
Interest rate (as a percent)	3.24%
Mortgages payable \| Maximum
INVESTMENT IN UNCONSOLIDATED JOINT VENTURES
Interest rate (as a percent)	5.97%