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v3.25.3

SUMMARY OF SIGNIFICANT ACCOUNTING POLICIES (Details) | 3 Months Ended | 9 Months Ended |
--- | --- | --- | ---
Sep. 30, 2025 USD ($) property partnership | Sep. 30, 2024 USD ($) | Sep. 30, 2025 USD ($) property partnership | Sep. 30, 2024 USD ($) | Dec. 31, 2024 USD ($)
Variable Interest Entity [Line Items] |  |  |  |  |
Total shareholders' equity | $ 973,125,000 |  | $ 973,125,000 |  | $ 1,075,980,000
Additional paid-in capital | 1,252,488,000 |  | 1,252,488,000 |  | 1,249,426,000
Accumulated other comprehensive income | 4,860,000 |  | 4,860,000 |  | 15,548,000
Noncontrolling interests | $ 608,916,000 |  | $ 608,916,000 |  | 687,367,000
Number of self storage properties | property | 1,069 |  | 1,069 |  |
Self storage properties, net | $ 4,666,096,000 |  | $ 4,666,096,000 |  | 4,812,496,000
Principal amount | 3,413,567,000 |  | $ 3,413,567,000 |  | 3,459,093,000
Property management fees as percent of monthly gross revenues and net sales revenue of unconsolidated real estate venture assets |  |  | 4.00% |  |
Tenant Insurance and Tenant Warranty Protection Plan Revenues |  |  |  |  |
Variable Interest Entity [Line Items] |  |  |  |  |
Revenue | 5,700,000 | $ 6,300,000 | $ 17,500,000 | $ 17,100,000 |
Retail Products and Supplies |  |  |  |  |
Variable Interest Entity [Line Items] |  |  |  |  |
Revenue | 400,000 | 500,000 | 1,200,000 | 1,500,000 |
Property Management, Call Center, and Platform Fees |  |  |  |  |
Variable Interest Entity [Line Items] |  |  |  |  |
Revenue | 4,700,000 | 4,700,000 | $ 14,100,000 | 13,500,000 |
Property management fees as percent of monthly gross revenues and net sales revenue of unconsolidated real estate venture assets |  |  | 6.00% |  |
Platform fees per unconsolidated real estate venture property per month |  |  | $ 1,250 |  |
Call center fees as percent of monthly gross revenues and net sales revenue of unconsolidated real estate venture assets |  |  | 1.00% |  |
Acquisition Fees |  |  |  |  |
Variable Interest Entity [Line Items] |  |  |  |  |
Revenue | 200,000 | 600,000 | $ 300,000 | 600,000 |
Tenant Warranty Protection or Tenant Insurance |  |  |  |  |
Variable Interest Entity [Line Items] |  |  |  |  |
Revenue | 7,000,000.0 | $ 6,100,000 | $ 21,300,000 | $ 15,600,000 |
Percent of total warranty protection plan proceeds received per unconsolidated real estate venture property |  |  | 50.00% |  |
Fixed rate mortgages payable | Mortgages |  |  |  |  |
Variable Interest Entity [Line Items] |  |  |  |  |
Principal amount | $ 199,167,000 |  | $ 199,167,000 |  | 200,793,000
VIE, Primary Beneficiary |  |  |  |  |
Variable Interest Entity [Line Items] |  |  |  |  |
Number of partnerships considered to be VIEs | partnership | 22 |  | 22 |  |
Number of self storage properties | property | 49 |  | 49 |  |
Self storage properties, net | $ 398,500,000 |  | $ 398,500,000 |  | 407,100,000
VIE, Primary Beneficiary | Fixed rate mortgages payable | Mortgages |  |  |  |  |
Variable Interest Entity [Line Items] |  |  |  |  |
Principal amount | 172,900,000 |  | 172,900,000 |  | $ 172,900,000
Revision of Prior Period, Error Correction, Adjustment |  |  |  |  |
Variable Interest Entity [Line Items] |  |  |  |  |
Total shareholders' equity | 112,100,000 |  | 112,100,000 |  |
Additional paid-in capital | 125,600,000 |  | 125,600,000 |  |
Accumulated other comprehensive income | 13,500,000 |  | 13,500,000 |  |
Noncontrolling interests | $ 112,100,000 |  | $ 112,100,000 |  |

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