Investments in Unconsolidated Real Estate Ventures - Summary of Composition of Investments (Details) - USD ($) $ in Thousands	Mar. 31, 2022	Dec. 31, 2021
Schedule of Equity Method Investments [Line Items]
Total investments in unconsolidated real estate ventures	$ 461,444	$ 462,885
Difference between the investments in unconsolidated real estate ventures and the net book value of the underlying assets	$ 17,600	18,600
Prudential Global Investment Management (PGIM) [Member]
Schedule of Equity Method Investments [Line Items]
Ownership interest (as percent)	50.00%
Total investments in unconsolidated real estate ventures	$ 207,221	208,421
Landmark
Schedule of Equity Method Investments [Line Items]
Total investments in unconsolidated real estate ventures	$ 26,369	28,298
Landmark \| Minimum
Schedule of Equity Method Investments [Line Items]
Ownership interest (as percent)	1.80%
Landmark \| Maximum
Schedule of Equity Method Investments [Line Items]
Ownership interest (as percent)	49.00%
CBREI Venture
Schedule of Equity Method Investments [Line Items]
Total investments in unconsolidated real estate ventures	$ 57,051	57,812
CBREI Venture \| Minimum
Schedule of Equity Method Investments [Line Items]
Ownership interest (as percent)	5.00%
CBREI Venture \| Maximum
Schedule of Equity Method Investments [Line Items]
Ownership interest (as percent)	64.00%
Canadian Pension Plan Investment Board (CPPIB)
Schedule of Equity Method Investments [Line Items]
Ownership interest (as percent)	55.00%
Total investments in unconsolidated real estate ventures	$ 48,179	48,498
J.P. Morgan Global Alternatives ("J.P. Morgan")
Schedule of Equity Method Investments [Line Items]
Ownership interest (as percent)	50.00%
Total investments in unconsolidated real estate ventures	$ 56,220	52,769
Berkshire Group
Schedule of Equity Method Investments [Line Items]
Ownership interest (as percent)	50.00%
Total investments in unconsolidated real estate ventures	$ 52,030	52,770
Brandywine
Schedule of Equity Method Investments [Line Items]
Ownership interest (as percent)	30.00%
Total investments in unconsolidated real estate ventures	$ 13,756	13,693
Other Investment
Schedule of Equity Method Investments [Line Items]
Total investments in unconsolidated real estate ventures	618	624
1101 17th Street [Member] \| Canadian Pension Plan Investment Board (CPPIB)
Schedule of Equity Method Investments [Line Items]
Total investments in unconsolidated real estate ventures	$ 0	$ 0

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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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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+ 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=120400017&loc=d3e572229-122910

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