Subsequent Events (Narrative) (Details) - Acquisition of Self-Storage Facilities Other Investments ft² in Millions, $ in Millions	1 Months Ended	9 Months Ended
Nov. 01, 2022 USD ($) ft² state storage_facility	Sep. 30, 2022 USD ($)
Subsequent Event [Line Items]
Total cost of acquisition		$ 501.9
Subsequent Event
Subsequent Event [Line Items]
Number of self-storage facilities acquired or under contract to be acquired \| storage_facility	33
Number of states self-storage facilities acquired or under contracts to be acquired \| state	6
Net rentable area (in square feet) \| ft²	1.7
Total cost of acquisition	$ 262.6

Fair value at acquisition-date of the assets transferred by the acquirer, liabilities incurred by the acquirer, and equity interests issued by the acquirer, including but not limited to, instruments or interests issued or issuable in consideration for the business combination.

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 805
-SubTopic 30
-Section 50
-Paragraph 1
-Subparagraph (b)
-URI https://asc.fasb.org/extlink&oid=126975305&loc=d3e6927-128479

Reference 2: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 805
-SubTopic 10
-Section 50
-Paragraph 2
-Subparagraph (g)
-URI https://asc.fasb.org/extlink&oid=79982066&loc=d3e1392-128463

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