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Schedule III - Real Estate and Accumulated Depreciation and Amortization (Details Textual) - USD ($) $ in Millions				12 Months Ended
	Feb. 19, 2021	Feb. 09, 2021	Jan. 28, 2021	Dec. 31, 2020
Subsequent Event [Member] | Waterman Plaza [Member]
Proceeds from Sale of Real Estate, Total			$ 3.5
Subsequent Event [Member] | Garden Gateway [Member]
Proceeds from Sale of Real Estate, Total	$ 11.2	$ 11.2
Building and Building Improvements [Member]
SEC Schedule, 12-28, Real Estate Companies, Investment in Real Estate and Accumulated Depreciation, Life Used for Depreciation (Year)				39 years

X

- Definition

Cash received for the sale of real estate that is not part of an investing activity during the current period.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 230
-SubTopic 10
-Section 45
-Paragraph 12
-Subparagraph (c)
-URI http://asc.fasb.org/extlink&oid=121586364&loc=d3e3179-108585

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X

- Definition

Useful life on which depreciation was computed for entities with a substantial portion of business acquiring and holding investment real estate, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days.

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 970
-SubTopic 360
-Section S99
-Paragraph 1
-Subparagraph (SX 210.12-28(Column I))
-URI http://asc.fasb.org/extlink&oid=120402810&loc=d3e638233-123024

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- Details

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X

- Details

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- Details

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