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Related Party Transactions - Other (Details) - USD ($)	3 Months Ended
	Mar. 31, 2020	Mar. 31, 2019
Chairman | General and administrative expense
RELATED PARTY TRANSACTIONS
Fees under compensation and services agreement	$ 74,500	$ 72,400
Vice Chairman
RELATED PARTY TRANSACTIONS
Fees under compensation and services agreement	29,800	28,900
Gould Investors L.P. | Real estate expenses
RELATED PARTY TRANSACTIONS
Insurance expense recognized of amounts reimbursed to related party	$ 246,000	$ 225,000

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Insurance expense recognized of amounts reimbursed to related party

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- Definition

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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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