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

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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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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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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	12 Months Ended
	Mar. 01, 2017 USD ($)	Feb. 28, 2007 USD ($)	Dec. 31, 2020 USD ($) item	Dec. 31, 2019 USD ($)	Dec. 31, 2018 USD ($) item	Oct. 03, 2005 USD ($) item
INVESTMENT IN UNCONSOLIDATED JOINT VENTURES
Investments in joint venture			$ 1,410,769	$ 1,430,402
Outstanding amount of mortgage			$ 283,444,533	$ 281,771,246
Hamilton Bay Apts
INVESTMENT IN UNCONSOLIDATED JOINT VENTURES
Investments in joint venture					$ 369,689	$ 2,500,000
Ownership interest (as a percent)					50.00%	50.00%
Number of units \| item					48	168
Number of units sold \| item			3			120
Number of units retained for long-term investment \| item						48
Term of debt		10 years
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
Capital contributions	$ 2,222,000
Gain on sale of assets			$ 429,000
Unsold units \| item					1
Purchase price of investments						$ 30,875,000
Borrowings		$ 4,750,000
Residential buildings \| Hamilton Bay Apts
INVESTMENT IN UNCONSOLIDATED JOINT VENTURES
Number of units \| item					48
Mortgages payable
INVESTMENT IN UNCONSOLIDATED JOINT VENTURES
Outstanding amount of mortgage			$ 283,445,000
Mortgages payable \| Minimum
INVESTMENT IN UNCONSOLIDATED JOINT VENTURES
Interest rate (as a percent)			3.53%
Mortgages payable \| Maximum
INVESTMENT IN UNCONSOLIDATED JOINT VENTURES
Interest rate (as a percent)			5.66%