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v3.25.1

Related Party Transactions - Additional Information (Detail1) - USD ($) |  |  |  | 12 Months Ended |  |  |
--- | --- | --- | --- | --- | --- | --- | ---
Apr. 29, 2024 | Nov. 01, 2023 | Jun. 01, 2022 | Dec. 31, 2024 | Dec. 31, 2023 | Aug. 07, 2024 | May 02, 2023 | May 01, 2022
Managed REIT Platform Expenses |  |  |  |  |  |  |  |
Related Party Transaction [Line Items] |  |  |  |  |  |  |  |
Reimbursements payable to SAM under the Administrative Services Agreement |  |  |  | $ 800,000 | $ 500,000 |  |  |
Managed REIT Platform Revenue |  |  |  |  |  |  |  |
Related Party Transaction [Line Items] |  |  |  |  |  |  |  |
Percentage of revenue from tenant protection programs |  |  |  | 0.10% |  |  |  |
SSGT II Merger Agreement |  |  |  |  |  |  |  |
Related Party Transaction [Line Items] |  |  |  |  |  |  |  |
Subordinated distribution value |  |  |  |  |  |  |  | $ 16,100,000
Gain resulting from acquisition of unconsolidated affiliates |  |  | $ 16,100,000 |  |  |  |  |
Write-off of carrying value related to intangible asset |  |  | 1,400,000 |  |  |  |  |
Change in deferred tax liability |  |  | $ 300,000 |  |  |  |  |
Strategic Transfer Agent Services, LLC |  |  |  |  |  |  |  |
Related Party Transaction [Line Items] |  |  |  |  |  |  |  |
Transition Fee | $ 150,000 |  |  |  |  |  |  |
TRS Subsidiary | Managed REIT Platform Revenue |  |  |  |  |  |  |  |
Related Party Transaction [Line Items] |  |  |  |  |  |  |  |
Percentage of revenue from tenant protection programs |  |  |  | 99.90% |  |  |  |
Pacific Oak Holding Group |  |  |  |  |  |  |  |
Related Party Transaction [Line Items] |  |  |  |  |  |  |  |
Variable interest entity non-voting ownership percentage |  |  |  | 17.50% |  |  |  |
Managed REIT |  |  |  |  |  |  |  |
Related Party Transaction [Line Items] |  |  |  |  |  |  |  |
Equity method investment, ownership percentage |  |  |  | 0.10% |  |  |  |
Managed REIT | TRS Subsidiary |  |  |  |  |  |  |  |
Related Party Transaction [Line Items] |  |  |  |  |  |  |  |
Equity method investment, ownership percentage |  |  |  | 99.90% |  |  |  |
Related Party | Managed REIT Platform Revenue |  |  |  |  |  |  |  |
Related Party Transaction [Line Items] |  |  |  |  |  |  |  |
Receivables due from related parties |  |  |  | $ 16,700,000 | 6,500,000 |  |  |
SmartStop Asset Management | Strategic Transfer Agent Services, LLC |  |  |  |  |  |  |  |
Related Party Transaction [Line Items] |  |  |  |  |  |  |  |
Percentage of membership interest |  |  |  | 100.00% |  |  |  |
SST VI |  |  |  |  |  |  |  |
Related Party Transaction [Line Items] |  |  |  |  |  |  |  |
Public offering extended expiry date |  | Sep. 13, 2025 |  |  |  |  |  |
Payables incurred to related parties |  |  |  | $ 2,400,000 |  |  |  |
Maximum commitment |  |  |  | $ 61,200,000 |  |  |  |
Variable entity maximum remaining share offering |  |  |  | 87,400,000 |  |  |  |
SST VI | Class Y And Z |  |  |  |  |  |  |  |
Related Party Transaction [Line Items] |  |  |  |  |  |  |  |
Share price |  |  |  |  |  | $ 10 |  |
SST VI Advisory Agreement | Pacific Oak Holding Group |  |  |  |  |  |  |  |
Related Party Transaction [Line Items] |  |  |  |  |  |  |  |
Variable interest entity non-voting ownership percentage |  |  |  | 17.50% |  |  |  |
SST VI Advisory Agreement | Class Z |  |  |  |  |  |  |  |
Related Party Transaction [Line Items] |  |  |  |  |  |  |  |
Percentage of offering cost without reimbursement |  |  |  | 1.50% |  |  |  |
Cost incurred in public offering |  |  |  | $ 44,000 | 5,000 |  |  |
Administrative Services Agreement |  |  |  |  |  |  |  |
Related Party Transaction [Line Items] |  |  |  |  |  |  |  |
Receivables due from related parties |  |  |  | 12,000 |  |  |  |
Administrative Services Agreement | Managed REIT Platform Expenses |  |  |  |  |  |  |  |
Related Party Transaction [Line Items] |  |  |  |  |  |  |  |
Administrative service fees |  |  |  | $ 200,000 | $ 700,000 |  |  |
SST VI OP | Series A Convertible Preferred Stock |  |  |  |  |  |  |  |
Related Party Transaction [Line Items] |  |  |  |  |  |  |  |
Preferred stock shares redeemed |  |  |  |  |  |  | 600,000 |
Interest payable |  |  |  |  |  |  | $ 15,100,000 |

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