Investments in Unconsolidated Real Estate Ventures - Summary of Composition of Investments (Details) $ in Thousands	1 Months Ended	3 Months Ended
Mar. 31, 2023 USD ($) property building	Mar. 31, 2023 USD ($) property building	Dec. 31, 2022 USD ($)
Schedule of Equity Method Investments [Line Items]
Total investments in unconsolidated real estate ventures	$ 312,651	$ 312,651	$ 299,881
Difference between the investments in unconsolidated real estate ventures and the net book value of the underlying assets	$ 6,900	$ 6,900	8,900
Number of Real Estate Properties \| property	51	51
One Commercial Building
Schedule of Equity Method Investments [Line Items]
Subordinated interest	10.00%	10.00%
Number of Real Estate Properties \| building	1	1
Disposal Group, Disposed of by Sale \| 4747 Bethesda Avenue
Schedule of Equity Method Investments [Line Items]
Percentage of ownership interest in assets sold	80.00%	80.00%
Gross Sales Price	$ 196,000	$ 196,000
Gross valuation of assets sold	$ 245,000	$ 245,000
Prudential Global Investment Management (PGIM)
Schedule of Equity Method Investments [Line Items]
Ownership interest (as percent)	50.00%	50.00%
Total investments in unconsolidated real estate ventures	$ 200,578	$ 200,578	203,529
J.P. Morgan Global Alternatives ("J.P. Morgan")
Schedule of Equity Method Investments [Line Items]
Ownership interest (as percent)	50.00%	50.00%
Total investments in unconsolidated real estate ventures	$ 66,771	$ 66,771	64,803
4747 Bethesda Avenue
Schedule of Equity Method Investments [Line Items]
Ownership interest (as percent)	20.00%	20.00%
Total investments in unconsolidated real estate ventures	$ 13,799	$ 13,799
4747 Bethesda Avenue \| 4747 Bethesda Avenue
Schedule of Equity Method Investments [Line Items]
Mortgage assumed due to sale of interests	$ 175,000	$ 175,000
Brandywine Realty Trust
Schedule of Equity Method Investments [Line Items]
Ownership interest (as percent)	30.00%	30.00%
Total investments in unconsolidated real estate ventures	$ 13,757	$ 13,757	13,678
CBREI Venture
Schedule of Equity Method Investments [Line Items]
Total investments in unconsolidated real estate ventures	$ 12,508	$ 12,508	12,516
CBREI Venture \| Minimum
Schedule of Equity Method Investments [Line Items]
Ownership interest (as percent)	9.90%	9.90%
CBREI Venture \| Maximum
Schedule of Equity Method Investments [Line Items]
Ownership interest (as percent)	10.00%	10.00%
Landmark
Schedule of Equity Method Investments [Line Items]
Ownership interest (as percent)	18.00%	18.00%
Total investments in unconsolidated real estate ventures	$ 4,669	$ 4,669	4,809
Other Investment
Schedule of Equity Method Investments [Line Items]
Total investments in unconsolidated real estate ventures	569	569	546
L'Enfant Plaza Assets
Schedule of Equity Method Investments [Line Items]
Total investments in unconsolidated real estate ventures	0	0	0
Certain Ventures
Schedule of Equity Method Investments [Line Items]
Total investments in unconsolidated real estate ventures	0	0	0
1101 17th Street \| Canadian Pension Plan Investment Board (CPPIB)
Schedule of Equity Method Investments [Line Items]
Total investments in unconsolidated real estate ventures	$ 0	$ 0	$ 0

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Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
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Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
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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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Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
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