Investments in Unconsolidated Real Estate Ventures - Summary of Composition of Investments (Details) - USD ($) $ in Thousands	Mar. 31, 2020	Dec. 31, 2019
Schedule of Equity Method Investments [Line Items]
Total investments in unconsolidated real estate ventures	$ 542,983	$ 543,026
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	$ 217,076	215,624
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	$ 112,808	109,911
Landmark
Schedule of Equity Method Investments [Line Items]
Total investments in unconsolidated real estate ventures	76,201	77,944
CBREI Venture
Schedule of Equity Method Investments [Line Items]
Total investments in unconsolidated real estate ventures	$ 67,084	68,405
Berkshire Group
Schedule of Equity Method Investments [Line Items]
Equity Method Investment, Ownership Percentage	50.00%
Total investments in unconsolidated real estate ventures	$ 46,859	46,391
Brandywine
Schedule of Equity Method Investments [Line Items]
Equity Method Investment, Ownership Percentage	30.00%
Total investments in unconsolidated real estate ventures	$ 13,741	13,830
Pacific Life Insurance Company
Schedule of Equity Method Investments [Line Items]
Equity Method Investment, Ownership Percentage	20.00%
Total investments in unconsolidated real estate ventures	$ 8,653	10,385
Other
Schedule of Equity Method Investments [Line Items]
Total investments in unconsolidated real estate ventures	$ 561	$ 536
Minimum \| Landmark
Schedule of Equity Method Investments [Line Items]
Equity Method Investment, Ownership Percentage	1.80%
Minimum \| CBREI Venture
Schedule of Equity Method Investments [Line Items]
Equity Method Investment, Ownership Percentage	5.00%
Maximum \| Landmark
Schedule of Equity Method Investments [Line Items]
Equity Method Investment, Ownership Percentage	49.00%
Maximum \| CBREI Venture
Schedule of Equity Method Investments [Line Items]
Equity Method Investment, Ownership Percentage	64.00%

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

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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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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