FAIR VALUE MEASUREMENTS - Summary (Details)	Mar. 31, 2022 USD ($) item Y	Dec. 31, 2021 USD ($) item Y
Line of Credit
FAIR VALUE MEASUREMENTS
Line of credit, gross	$ 5,140,000	$ 11,700,000
Mortgages payable
FAIR VALUE MEASUREMENTS
Estimated fair value of mortgages payable	400,493,000	419,354,000
Carrying value of mortgage loans	401,140,000	399,660,000
Excess of fair value over carrying value		$ 19,694,000
Excess of carrying value over fair value	$ 647,000
Mortgages payable \| Blended market interest rate
FAIR VALUE MEASUREMENTS
Long-term debt, measurement input \| item	0.0430	0.0320
Mortgages payable \| Remaining term to maturity
FAIR VALUE MEASUREMENTS
Long-term debt, measurement input \| Y	6.2	6.4

Represents the amount of difference between the carrying value and the fair value.

No definition available.

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- Definition

Represents the amount of difference between the fair value and carrying value.

+ References

No definition available.

+ Details

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- Definition

The carrying value as of the balance sheet date of the current and noncurrent portions of long-term obligations drawn from a line of credit before netting of deferred finance costs, which is a bank's commitment to make loans up to a specific amount. Examples of items that might be included in the application of this element may consist of letters of credit, standby letters of credit, and revolving credit arrangements, under which borrowings can be made up to a maximum amount as of any point in time conditional on satisfaction of specified terms before, as of and after the date of drawdowns on the line. Includes short-term obligations that would normally be classified as current liabilities but for which (a) post balance sheet date issuance of a long term obligation to refinance the short term obligation on a long term basis, or (b) the enterprise has entered into a financing agreement that clearly permits the enterprise to refinance the short-term obligation on a long term basis and the following conditions are met (1) the agreement does not expire within 1 year and is not cancellable by the lender except for violation of an objectively determinable provision, (2) no violation exists at the BS date, and (3) the lender has entered into the financing agreement is expected to be financially capable of honoring the agreement.

+ References

No definition available.

+ Details

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- Definition

Carrying value as of the balance sheet date, including the current and noncurrent portions, of collateralized debt obligations before netting of deferred finance costs (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.

+ References

No definition available.

+ Details

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- Definition

Fair value portion of debt instrument payable, including, but not limited to, notes payable and loans payable.

+ References

Reference 1: http://www.xbrl.org/2003/role/exampleRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 470
-SubTopic 20
-Section 55
-Paragraph 69C
-URI http://asc.fasb.org/extlink&oid=123466577&loc=SL123495737-112612

Reference 2: http://www.xbrl.org/2003/role/exampleRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 470
-SubTopic 20
-Section 55
-Paragraph 69B
-URI http://asc.fasb.org/extlink&oid=123466577&loc=SL123495735-112612

Reference 3: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 825
-SubTopic 10
-Section 50
-Paragraph 10
-URI http://asc.fasb.org/extlink&oid=123594938&loc=d3e13433-108611

Reference 4: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 470
-SubTopic 20
-Section 50
-Paragraph 1D
-Subparagraph (c)
-URI http://asc.fasb.org/extlink&oid=123466505&loc=SL123495340-112611

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Period Type:	instant

- Definition

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.

+ References

No definition available.

+ Details

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- Definition

Value of input used to measure long-term debt.

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 820
-SubTopic 10
-Section 50
-Paragraph 2
-Subparagraph (bbb)(2)
-URI http://asc.fasb.org/extlink&oid=123874694&loc=d3e19207-110258

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