Percentage of subordinated interest held through an unconsolidated real estate venture.

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- Definition

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.

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Topic 323
-SubTopic 10
-Name Accounting Standards Codification
-Section 50
-Paragraph 3
-Subparagraph (a)(3)
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147481687/323-10-50-3

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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://www.xbrl.org/2003/role/disclosureRef
-Topic 825
-SubTopic 10
-Name Accounting Standards Codification
-Section 50
-Paragraph 28
-Subparagraph (f)
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147482907/825-10-50-28

Reference 2: http://www.xbrl.org/2003/role/disclosureRef
-Topic 323
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-Publisher FASB
-URI https://asc.fasb.org/1943274/2147481687/323-10-50-3

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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

The amount of revenue derived from managing real estate properties.

+ References

No definition available.

+ Details

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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://www.xbrl.org/2009/role/commonPracticeRef
-Topic 944
-SubTopic 210
-Name Accounting Standards Codification
-Section S99
-Paragraph 1
-Subparagraph (SX 210.7-03(a)(1)(d))
-Publisher FASB
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Reference 2: http://www.xbrl.org/2009/role/commonPracticeRef
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-Name Accounting Standards Codification
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-Publisher FASB
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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

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Topic 235
-SubTopic 10
-Name Accounting Standards Codification
-Section S50
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-Topic 235
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Reference 4: http://www.xbrl.org/2003/role/disclosureRef
-Topic 323
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-Name Accounting Standards Codification
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- Details

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Investments in Unconsolidated Real Estate Ventures - Summary of Composition of Investments (Details) $ in Thousands	3 Months Ended
	Mar. 31, 2026 USD ($) property building	Mar. 31, 2025 USD ($)	Dec. 31, 2025 USD ($) building
Investments in Unconsolidated Real Estate Ventures
Total investments in unconsolidated real estate ventures	$ 105,348		$ 105,711
Number of real estate properties \| property	38
Difference between the investments in unconsolidated real estate ventures and the net book value of the underlying assets	$ 1,900		$ 2,000
One Commercial Building
Investments in Unconsolidated Real Estate Ventures
Subordinated interest	10.00%		10.00%
Number of real estate properties \| building	1		1
J.P. Morgan Global Alternatives ("J.P. Morgan")
Investments in Unconsolidated Real Estate Ventures
Ownership interest (as percent)	50.00%
Total investments in unconsolidated real estate ventures	$ 71,736		$ 71,550
Dulles View Venture
Investments in Unconsolidated Real Estate Ventures
Ownership interest (as percent)	60.00%
Total investments in unconsolidated real estate ventures	$ 18,584		18,536
4747 Bethesda Venture
Investments in Unconsolidated Real Estate Ventures
Ownership interest (as percent)	20.00%
Total investments in unconsolidated real estate ventures	$ 7,424		8,085
Brandywine Realty Trust
Investments in Unconsolidated Real Estate Ventures
Ownership interest (as percent)	30.00%
Total investments in unconsolidated real estate ventures	$ 7,042		6,968
Other
Investments in Unconsolidated Real Estate Ventures
Total investments in unconsolidated real estate ventures	562		$ 572
Investments in unconsolidated real estate ventures
Investments in Unconsolidated Real Estate Ventures
Property Management Fee Revenue	$ 2,800	$ 2,800