Variable Interest Entities (Details Textual) $ in Thousands	Sep. 30, 2021 USD ($) apartment_home	Dec. 31, 2020 USD ($)
Schedule Of Investment Income Reported Amounts By Category [Line Items]
Mezzanine investment	$ 330,016	$ 307,362
San Diego Communities [Member]
Schedule Of Investment Income Reported Amounts By Category [Line Items]
Number of apartment communities \| apartment_home	4
Mezzanine investment	$ 13,000
Financial Guarantee [Member]
Schedule Of Investment Income Reported Amounts By Category [Line Items]
Customary guarantees	$ 143,700

This item represents a non-contingent liability for the fair value of an obligation to stand ready to perform over the term of a guaranty issued in the event that specified triggering events or conditions occur.

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
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Reference 2: http://fasb.org/us-gaap/role/ref/legacyRef
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-Name Accounting Standards Codification
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Reference 3: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 460
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Reference 4: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
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-URI http://asc.fasb.org/extlink&oid=121555860&loc=d3e11049-110243

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Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	instant