Represents the period for which the entity is required to make interest only payments on the debt instrument.

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

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Represents the number of units sold.

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

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Period of time between issuance and maturity of debt instrument, in PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days.

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This element represents the aggregate cost of investments accounted for under the equity method of accounting.

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The percentage of ownership of common stock or equity participation in the investee accounted for under the equity method of accounting.

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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 net realized gain (loss) on investments sold during the period, not including gains (losses) on securities separately or otherwise categorized as trading, available-for-sale, or held-to-maturity, which, for cash flow reporting, is a component of proceeds from investing activities.

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Period between issuance and maturity of long-term debt, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents reported fact of one year, five months, and thirteen days.

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

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Total contributions made by each class of partners (i.e., general, limited and preferred partners).

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The cash inflow during the period from additional borrowings in aggregate debt. Includes proceeds from short-term and long-term debt.

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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 1025) (Details)			12 Months Ended
	Jul. 08, 2016 USD ($)	Mar. 02, 2005 USD ($) item	Dec. 31, 2018 USD ($) item	Dec. 31, 2017 USD ($) item	Dec. 31, 2016 USD ($) item
INVESTMENT IN UNCONSOLIDATED JOINT VENTURES
Investments in joint venture \| $			$ 1,985,680	$ 7,212,044	$ 8,336,505
Number of units			1,033	1,033	1,033
Number of units sold			16	29
Unsold units			3	34	38
Number of units retained for long-term investment			(689)	(689)	(689)
Outstanding amount of mortgage \| $			$ 252,370,843	$ 233,221,258
Mortgages payable
INVESTMENT IN UNCONSOLIDATED JOINT VENTURES
Outstanding amount of mortgage \| $			252,371,000
Hamilton 1025
INVESTMENT IN UNCONSOLIDATED JOINT VENTURES
Investments in joint venture \| $		$ 2,352,000	$ 188,090	$ 1,051,759	$ 2,097,151
Ownership interest (as a percent)		50.00%	50.00%	50.00%	50.00%
Number of units		176	176	176	176
Number of units sold		127	16	20
Unsold units			2	17	37
Number of units retained for long-term investment		49
Capital contributions \| $	$ 2,359,500
Number of units under a purchase and sale agreement			1
Term of debt		10 years
Interest rate (as a percent)		5.67%
Period for which the entity is required to make interest only payments		5 years
Amortization period of debt		30 years
Purchase price of investments \| $		$ 23,750,000
Borrowings \| $		$ 5,000,000
Gain on sale of assets \| $			$ 1,973,000	$ 2,380,000
Hamilton 1025 \| General Partnership
INVESTMENT IN UNCONSOLIDATED JOINT VENTURES
Number of units			3
Residential buildings
INVESTMENT IN UNCONSOLIDATED JOINT VENTURES
Number of units			1,030	1,030	1,030
Residential buildings \| Hamilton 1025
INVESTMENT IN UNCONSOLIDATED JOINT VENTURES
Number of units			175	175	175