Investment in Unconsolidated Ventures - Summary of Real Estate Properties Owned (Details) - USD ($) $ in Thousands	Sep. 30, 2021	Dec. 31, 2020
Schedule of Equity Method Investments [Line Items]
Land	$ 29,489	$ 25,585
Building	220,272	154,854
Building improvements	8,839	10,590
Real estate properties	258,600	191,029
Accumulated depreciation	(33,980)	(30,837)
Total real estate properties, net	224,620	160,192
Unconsolidated Joint Ventures
Schedule of Equity Method Investments [Line Items]
Land	105,480	148,341
Building	827,494	1,029,739
Building improvements	35,949	42,698
Real estate properties	968,923	1,220,778
Accumulated depreciation	(144,299)	(145,600)
Total real estate properties, net	$ 824,624	$ 1,075,178

Investment Building

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Investment Building Improvements

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- Definition

Amount before accumulated depletion of real estate held for productive use, excluding land held for sale.

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Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 210
-SubTopic 10
-Section S99
-Paragraph 1
-Subparagraph (SX 210.5-02.13)
-URI http://asc.fasb.org/extlink&oid=120391452&loc=d3e13212-122682

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The cumulative amount of depreciation for real estate property held for investment purposes.

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Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
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Amount of real estate investment property which may include the following: (1) land available-for-sale; (2) land available-for-development; (3) investments in building and building improvements; (4) tenant allowances; (5) developments in-process; (6) rental properties; and (7) other real estate investments.

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Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 944
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Amount of real estate investments, net of accumulated depreciation, which may include the following: (1) land available-for-sale; (2) land available-for-development; (3) investments in building and building improvements; (4) tenant allowances; (5) developments in-process; (6) rental properties; (7) other real estate investments; (8) real estate joint ventures; and (9) unconsolidated real estate and other joint ventures not separately presented.

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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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