Related Party Transactions (Details) - USD ($)	3 Months Ended
Mar. 31, 2019	Mar. 31, 2018
Related Party Transaction
Share based compensation charged to operations	$ 954,000	$ 826,000
Majestic
Related Party Transaction
Fees under compensation and services agreement	704,000	678,000
Property management costs allocated to real estate expenses	324,000	299,000
Additional payment for the entity's share of all direct office expenses	54,000	54,000
Executive officers and others
Related Party Transaction
Share based compensation charged to operations	470,000	417,000
Joint Venture Partners and Affiliates
Related Party Transaction
Real estate property management costs	21,000	43,000
Chairman \| General and administrative expense
Related Party Transaction
Quarterly fees under compensation and services agreement	72,400	69,000
Vice Chairman \| General and administrative expense
Related Party Transaction
Quarterly fees under compensation and services agreement	28,900	27,500
Gould Investors L.P. \| Real estate expenses
Related Party Transaction
Insurance expense recognized of amounts reimbursed to related party	$ 225,000	201,000
Net lease tenants \| Majestic
Related Party Transaction
Property management costs (as a percent)	1.50%
Operating lease tenants \| Majestic
Related Party Transaction
Property management costs (as a percent)	2.00%
Unconsolidated Joint Ventures
Related Party Transaction
Aggregate fees paid to other partners	$ 26,000	51,000
Decrease in equity earnings, joint venture transaction	$ 13,000	$ 25,000

Aggregate fees paid to other partners of the venture.

No definition available.

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- Definition

Reduction of equity in earnings of unconsolidated joint ventures on the consolidated statement of income.

+ References

No definition available.

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- Definition

Insurance expense recognized of amounts reimbursed to related party

+ References

No definition available.

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- Definition

Represents the aggregate costs related to management of properties during the reporting period.

+ References

No definition available.

+ Details

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- Definition

Represents the amount of additional payment to related party for the share of direct office expenses.

+ References

No definition available.

+ Details

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- Definition

Represents the amount to be paid under the agreement with the related party.

+ References

No definition available.

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- Definition

Represents the amount of property management costs allocated to real estate expenses.

+ References

No definition available.

+ Details

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- Definition

Represents the quarterly amount to be paid under the agreement with the related party for the current fiscal year.

+ References

No definition available.

+ Details

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- Definition

Represents the expense recognized during the period arising from equity-based compensation arrangements (for example, shares of stock, unit, stock options or other equity instruments) with employees, directors and certain consultants qualifying for treatment as employees.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 718
-SubTopic 10
-Section 50
-Paragraph 1
-Subparagraph (b)
-URI http://asc.fasb.org/extlink&oid=109197908&loc=d3e5047-113901

Reference 2: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 718
-SubTopic 10
-Section S99
-Paragraph 1
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-URI http://asc.fasb.org/extlink&oid=115993241&loc=d3e301413-122809

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-Publisher FASB
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-SubTopic 10
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-Paragraph 2
-Subparagraph (h)(1)(i)
-URI http://asc.fasb.org/extlink&oid=109197908&loc=d3e5070-113901

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- Definition

The percentage charged for managing real estate properties.

+ References

No definition available.

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- 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.

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