Organization And Description Of Business (Narrative) (Details) shares in Millions, ft² in Millions	9 Months Ended
	Sep. 30, 2020 ft² item property state shares
Organization And Description Of Business [Line Items]
The Company's ownership percentage of the limited partnership	79.00%
Rentable area (in square feet) | ft²	27.5
Number of states with rentable commercial space | state	6
Number of parks | item	97
Number of buildings | item	672
Managed Properties [Member]
Organization And Description Of Business [Line Items]
Rentable area (in square feet) | ft²	0.4
Highgate at the Mile [Member]
Organization And Description Of Business [Line Items]
Number of Units in Multi-Family Asset | property	395
Brentford at The Mile [Member]
Organization And Description Of Business [Line Items]
Number of Units in Multi-Family Asset | property	411
PS [Member]
Organization And Description Of Business [Line Items]
Shares owned by Public Storage | shares	7.2
Affiliate's percent ownership of the Company's common equity	41.60%
Aggregate shares owned if partnership units are redeemed | shares	14.5
Investment in Joint Venture [Member] | Highgate at the Mile [Member]
Organization And Description Of Business [Line Items]
Economic interest in joint venture, percentage	95.00%
Investment in Joint Venture [Member] | Brentford at The Mile [Member]
Organization And Description Of Business [Line Items]
Economic interest in joint venture, percentage	98.20%