Related Party Transactions (Narrative) (Details) $ in Thousands	3 Months Ended		9 Months Ended
	Sep. 30, 2020 USD ($) item	Sep. 30, 2019 USD ($)	Sep. 30, 2020 USD ($) item	Sep. 30, 2019 USD ($)	Dec. 31, 2019 USD ($)
Related Party Transaction [Line Items]
Interest and other income	$ 230	$ 1,384	$ 1,012	$ 2,766
Royalty-free license agreement written notice of termination period minimum (in months)			6 months
Number of assets owned that are maintained by Public Storage | item	2		2
Property management contract written notice of termination period minimum (in days)			60 days
Reimbursement to related party	$ 400	400	$ 800	800
Due to related parties	100		100		$ 100
Property Management [Member]
Related Party Transaction [Line Items]
Interest and other income	100	100	200	200
Operating expenses allocated to operating party	100	100	300	300
Maximum [Member]
Related Party Transaction [Line Items]
Management fee expenses	100	100	100	100
Costs allocated from related party	100	100	100	100
Reimbursement from related party	$ 100	$ 100	$ 100	$ 100