RELATED PARTY TRANSACTIONS - Other (Details) - USD ($)	12 Months Ended
Dec. 31, 2020	Dec. 31, 2019	Dec. 31, 2018
Chairman \| General and administrative expense
Related Party Transactions
Aggregate fees paid	$ 298,000	$ 289,000	$ 276,000
Vice Chairman \| General and administrative expense
Related Party Transactions
Aggregate fees paid	$ 119,000	$ 116,000	110,000
Gould Investors L.P.
Related Party Transactions
Number of common stock shares owned by the related party	1,894,883	1,894,883
Ownership percentage held by a related party	9.20%	9.00%
Amount of insurance reimbursed	$ 1,168,000	$ 1,025,000	912,000
Gould Investors L.P. \| Real estate expenses
Related Party Transactions
Insurance expense recognized of amounts reimbursed to related party	$ 1,091,000	$ 927,000	$ 877,000

Number of shares of common stock owned by related party

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- Definition

Insurance expense recognized of amounts reimbursed to related party

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The aggregate amount of payments for key management services.

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Represents the amount of reimbursement of property insurance under the related party transactions.

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Represents the percentage of ownership held by the related party.

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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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No definition available.

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