Investments in Unconsolidated Real Estate Ventures - Summary of Composition of Investments (Details) $ in Thousands	Jun. 30, 2025 USD ($) property building	Dec. 31, 2024 USD ($) building
Investments in Unconsolidated Real Estate Ventures
Total investments in unconsolidated real estate ventures	$ 93,859	$ 93,654
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	$ 11,100	$ 10,600
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	$ 74,447	$ 74,188
4747 Bethesda Venture
Investments in Unconsolidated Real Estate Ventures
Ownership interest (as percent)	20.00%
Total investments in unconsolidated real estate ventures	$ 9,621	10,813
Brandywine Realty Trust
Investments in Unconsolidated Real Estate Ventures
Ownership interest (as percent)	30.00%
Total investments in unconsolidated real estate ventures	$ 6,962	6,954
Other
Investments in Unconsolidated Real Estate Ventures
Total investments in unconsolidated real estate ventures	2,829	1,699
Certain Ventures
Investments in Unconsolidated Real Estate Ventures
Total investments in unconsolidated real estate ventures	0	0
1101 17th Street \| Canadian Pension Plan Investment Board (CPPIB)
Investments in Unconsolidated Real Estate Ventures
Total investments in unconsolidated real estate ventures	$ 0	$ 0

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

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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

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

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

+ References

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

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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.

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