Business - Ownership Breakdown (Details)	Sep. 30, 2021 Property ApartmentUnit
Property/Unit schedule
Properties \| Property	307
Apartment Units \| ApartmentUnit	79,322
Wholly Owned Properties
Property/Unit schedule
Properties \| Property	290
Apartment Units \| ApartmentUnit	75,548
Partially Owned Properties – Consolidated
Property/Unit schedule
Properties \| Property	17
Apartment Units \| ApartmentUnit	3,774

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.

No definition available.

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Namespace Prefix:	us-gaap_
Data Type:	xbrli:stringItemType
Balance Type:	na
Period Type:	duration