Distribution from cost method investment.

No definition available.

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- Definition

Joint venture interest percentage.

+ References

No definition available.

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- Definition

Number of joint ventures.

+ References

No definition available.

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- Definition

Undivided interest in property percentage.

+ References

No definition available.

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- Definition

Area of a real estate property.

+ References

No definition available.

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- Definition

Amount, after adjustment, of cost-method investment. Adjustments include, but are not limited to, dividends received in excess of earnings after date of investment that are considered a return of investment and other than temporary impairments.

+ References

No definition available.

+ Details

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- Definition

The percentage of ownership of common stock or equity participation in the investee accounted for under the equity method of accounting.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 323
-SubTopic 10
-Section 50
-Paragraph 3
-Subparagraph (a)(1)
-URI http://asc.fasb.org/extlink&oid=114001798&loc=d3e33918-111571

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- Definition

The number of businesses acquired by the entity during the period.

+ References

No definition available.

+ Details

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- Definition

The number of real estate properties owned as of the balance sheet date.

+ References

No definition available.

+ Details

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- Definition

Amount of real estate investment property which may include the following: (1) land available-for-sale; (2) land available-for-development; (3) investments in building and building improvements; (4) tenant allowances; (5) developments in-process; (6) rental properties; and (7) other real estate investments.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 944
-SubTopic 210
-Section S99
-Paragraph 1
-Subparagraph (SX 210.7-03.1(d))
-URI http://asc.fasb.org/extlink&oid=119400593&loc=d3e572229-122910

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- Definition

The carrying amount of investments in unconsolidated real estate and other joint ventures not separately presented. This includes direct and indirect investments.

+ References

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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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Investments in and Advances to Unconsolidated Affiliates - Fund Investments - Additional Information (Details)		12 Months Ended
	Jun. 29, 2019 USD ($)	Dec. 31, 2014 property JointVenture	Sep. 30, 2020 USD ($) property	Jun. 30, 2020 property	May 26, 2020 USD ($) property	Dec. 31, 2019 USD ($)	Aug. 21, 2019 USD ($) ft²	Apr. 30, 2019 USD ($) ft²	Mar. 19, 2019 USD ($) ft²	Oct. 31, 2018 segment
Schedule of Equity Method Investments [Line Items]
Number of retail properties \| property			187
Closing Costs			$ 3,899,993,000			$ 3,846,140,000
Fund V Family Center at Riverdale
Schedule of Equity Method Investments [Line Items]
Equity method investment, ownership percentage			89.42%
Tri City Plaza
Schedule of Equity Method Investments [Line Items]
Equity method investment, ownership percentage			90.00%
Frederick County Acquisitions
Schedule of Equity Method Investments [Line Items]
Equity method investment, ownership percentage			90.00%
BSP I and BSP II
Schedule of Equity Method Investments [Line Items]
Equity method investment, ownership percentage		50.00%
Number of Joint Ventures \| JointVenture		2
Broughton St. Portfolio Savannah, GA
Schedule of Equity Method Investments [Line Items]
Purchase Price					$ 1,200,000
Equity method investment, ownership percentage			100.00%
Number of businesses acquired \| property		23
Number of retail properties \| property					2
Closing Costs					$ 100,000
Fund I Vs Broughton Street Portfolio Venture
Schedule of Equity Method Investments [Line Items]
Number of retail properties \| property		8
Fund IV \| Disposed of by sale \| Broughton St. Portfolio Savannah, GA
Schedule of Equity Method Investments [Line Items]
Number of retail properties \| property		2
BSP I
Schedule of Equity Method Investments [Line Items]
Equity method investment, ownership percentage										100.00%
BSP I \| Consolidated Entity
Schedule of Equity Method Investments [Line Items]
Number of retail properties \| segment										11
BSP II \| Consolidated Affiliates
Schedule of Equity Method Investments [Line Items]
Number of retail properties \| property				2
Fund III's Storage Post venture
Schedule of Equity Method Investments [Line Items]
Distribution from cost method investment	$ 1,600,000
Cost method investments	0
Fund III's Storage Post venture \| Partnership Interest
Schedule of Equity Method Investments [Line Items]
Distribution from cost method investment	$ 400,000
Riverdale, Utah \| Fund V Family Center at Riverdale
Schedule of Equity Method Investments [Line Items]
Joint venture interest percentage									99.35%
Undivided interest in property percentage									90.00%
Square footage of real estate property (in square feet) \| ft²									428,000
Purchase Price									$ 48,500,000
Vernon, Connecticut \| Tri City Plaza
Schedule of Equity Method Investments [Line Items]
Joint venture interest percentage								90.00%
Square footage of real estate property (in square feet) \| ft²								300,000
Purchase Price								$ 36,700,000
Frederick County, Maryland \| Frederick County Acquisitions \| 225,000 Square Foot Property
Schedule of Equity Method Investments [Line Items]
Joint venture interest percentage							90.00%
Square footage of real estate property (in square feet) \| ft²							225,000
Purchase Price							$ 21,800,000
Frederick County, Maryland \| Frederick County Acquisitions \| 300,00 Square Foot Property
Schedule of Equity Method Investments [Line Items]
Joint venture interest percentage							90.00%
Square footage of real estate property (in square feet) \| ft²							300,000
Purchase Price							$ 33,100,000