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

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Represents the carrying value of equity method investment as of the balance sheet date.

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- Definition

Represents the aggregate purchase price of real estate properties acquired by the entity.

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- Definition

Face (par) amount of debt instrument at time of issuance.

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

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- Definition

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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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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No definition available.

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Total distributions to each class of partners (i.e., general, limited and preferred partners).

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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 (Dexter) (Details)			1 Months Ended	12 Months Ended
	May 31, 2018 USD ($)	Oct. 28, 2009 USD ($) item	Oct. 31, 2009 USD ($)	Dec. 31, 2021 USD ($) item	Dec. 31, 2020 USD ($) item	Dec. 31, 2019 USD ($) item
INVESTMENT IN UNCONSOLIDATED JOINT VENTURES
Investments in joint venture				$ 1,455,888	$ 1,410,769
Outstanding amount of mortgage				370,481,390	283,444,533
Distribution to the Partnership				4,673,140	$ 4,675,754	$ 4,696,893
Mortgages payable
INVESTMENT IN UNCONSOLIDATED JOINT VENTURES
Outstanding amount of mortgage				$ 370,481,000
Dexter Park
INVESTMENT IN UNCONSOLIDATED JOINT VENTURES
Investments in joint venture		$ 15,925,000
Ownership interest (as a percent)		40.00%		40.00%	40.00%	40.00%
Number of units \| item				409	409	409
Purchase price of real estate properties		$ 129,500,000
Outstanding amount of mortgage	$ 82,000,000			$ 124,585,336	$ 124,520,713	$ 124,456,090
Distribution to the Partnership	41,200,000
Dexter Park \| Mortgage, 5.57%, Due 2019
INVESTMENT IN UNCONSOLIDATED JOINT VENTURES
Loan amount			$ 89,914,000
Interest rate (as a percent)		5.57%
Period for which the entity is required to make interest only payments			2 years
Amortization period of debt		30 years
John Hancock \| Dexter Park
INVESTMENT IN UNCONSOLIDATED JOINT VENTURES
Loan amount	$ 125,000,000
Interest rate (as a percent)	3.99%
Outstanding amount of mortgage				125,000,000
General Partnership
INVESTMENT IN UNCONSOLIDATED JOINT VENTURES
Distribution to the Partnership				$ 46,731	$ 46,757	$ 46,969
General Partnership \| Dexter Park
INVESTMENT IN UNCONSOLIDATED JOINT VENTURES
Distribution to the Partnership	$ 16,500,000
Carrying value	$ 0
Residential buildings \| Dexter Park
INVESTMENT IN UNCONSOLIDATED JOINT VENTURES
Number of units \| item		409		409	409	409