Difference between amount at which an investment accounted for under the equity method of accounting is carried (reported) on the balance sheet and amount of underlying equity in net assets the reporting Entity has in the investee.

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)(3)
-URI http://asc.fasb.org/extlink&oid=114001798&loc=d3e33918-111571

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

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 Unconsolidated Real Estate Ventures - Summary of Composition of Investments (Details) - USD ($) $ in Thousands	Dec. 31, 2020	Jun. 30, 2020	Dec. 31, 2019
Schedule of Equity Method Investments [Line Items]
Total investments in unconsolidated real estate ventures	$ 461,369		$ 543,026
Difference between the investments in unconsolidated real estate ventures and the net book value of the underlying assets	$ 18,900		14,300
Prudential Global Investment Management (PGIM)
Schedule of Equity Method Investments [Line Items]
Equity Method Investment, Ownership Percentage	50.00%
Total investments in unconsolidated real estate ventures	$ 216,939		215,624
Landmark
Schedule of Equity Method Investments [Line Items]
Total investments in unconsolidated real estate ventures	$ 66,724		77,944
Landmark \| Minimum
Schedule of Equity Method Investments [Line Items]
Equity Method Investment, Ownership Percentage	1.80%
Landmark \| Maximum
Schedule of Equity Method Investments [Line Items]
Equity Method Investment, Ownership Percentage	49.00%
CBREI Venture
Schedule of Equity Method Investments [Line Items]
Total investments in unconsolidated real estate ventures	$ 65,190		68,405
CBREI Venture \| Minimum
Schedule of Equity Method Investments [Line Items]
Equity Method Investment, Ownership Percentage	5.00%
CBREI Venture \| Maximum
Schedule of Equity Method Investments [Line Items]
Equity Method Investment, Ownership Percentage	64.00%
Canadian Pension Plan Investment Board (CPPIB)
Schedule of Equity Method Investments [Line Items]
Equity Method Investment, Ownership Percentage	55.00%
Total investments in unconsolidated real estate ventures	$ 47,522		109,911
Berkshire Group
Schedule of Equity Method Investments [Line Items]
Equity Method Investment, Ownership Percentage	50.00%
Total investments in unconsolidated real estate ventures	$ 50,649		46,391
Brandywine Realty Trust
Schedule of Equity Method Investments [Line Items]
Equity Method Investment, Ownership Percentage	30.00%
Total investments in unconsolidated real estate ventures	$ 13,710		13,830
Pacific Life Insurance Company
Schedule of Equity Method Investments [Line Items]
Total investments in unconsolidated real estate ventures		$ 0	10,385
Other
Schedule of Equity Method Investments [Line Items]
Total investments in unconsolidated real estate ventures	$ 635		$ 536