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ORGANIZATION AND NATURE OF OPERATIONS (Details) storage_unit in Thousands, ft² in Millions | 9 Months Ended
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Sep. 30, 2025 ft² state metropolitan_statistical_area property storage_unit
Schedule of Equity Method Investments [Line Items] |
Number of top metropolitan statistical areas for focus of operations | metropolitan_statistical_area | 100
Number of self storage properties | 1,069
Number of states in which self storage properties are located | state | 37
Total rentable square feet in self storage properties | ft² | 69.8
Number of units in real estate property | storage_unit | 551
Consolidated properties |
Schedule of Equity Method Investments [Line Items] |
Number of self storage properties | 807
Number of states in which self storage properties are located | state | 33
Total rentable square feet in self storage properties | ft² | 51.6
Number of storage units | storage_unit | 406
Unconsolidated properties | 2018 Joint Venture |
Schedule of Equity Method Investments [Line Items] |
Company's equity interest in unconsolidated real estate ventures (as a percent) | 25.00%
Unconsolidated properties | 2016 Joint Venture |
Schedule of Equity Method Investments [Line Items] |
Company's equity interest in unconsolidated real estate ventures (as a percent) | 25.00%
Unconsolidated properties | Joint Venture |
Schedule of Equity Method Investments [Line Items] |
Number of self storage properties | 262
Number of states in which self storage properties are located | state | 24
Total rentable square feet in self storage properties | ft² | 18.2
Number of units in real estate property | storage_unit | 145
Unconsolidated properties | Joint Venture | 2018 Joint Venture |
Schedule of Equity Method Investments [Line Items] |
Number of self storage properties | 104
Number of states in which self storage properties are located | state | 17
Total rentable square feet in self storage properties | ft² | 7.9
Number of units in real estate property | storage_unit | 65
Company's equity interest in unconsolidated real estate ventures (as a percent) | 25.00%
Unconsolidated properties | Joint Venture | 2016 Joint Venture |
Schedule of Equity Method Investments [Line Items] |
Number of self storage properties | 81
Number of states in which self storage properties are located | state | 13
Total rentable square feet in self storage properties | ft² | 5.7
Number of units in real estate property | 47,000
Company's equity interest in unconsolidated real estate ventures (as a percent) | 25.00%

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