Business - Ownership Breakdown (Details)	Sep. 30, 2020 Property ApartmentUnit
Property/Unit schedule
Properties \| Property	305
Apartment Units \| ApartmentUnit	78,568
Wholly Owned Properties
Property/Unit schedule
Properties \| Property	288
Apartment Units \| ApartmentUnit	75,007
Master-Leased Property Consolidated
Property/Unit schedule
Properties \| Property	1
Apartment Units \| ApartmentUnit	162
Partially Owned Properties – Consolidated
Property/Unit schedule
Properties \| Property	16
Apartment Units \| ApartmentUnit	3,399

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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Data Type:	xbrli:stringItemType
Balance Type:	na
Period Type:	duration