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Related Party Transactions - Additional Information (Detail) |  |  |  |  |  |  |  |  |  |  |  | 12 Months Ended |  |  |  |  |  |  |  |  |
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Dec. 16, 2024 USD ($) | Jun. 28, 2024 USD ($) | May 02, 2024 USD ($) | Dec. 15, 2023 USD ($) | Jun. 13, 2023 USD ($) | May 02, 2023 USD ($) | Jan. 30, 2023 USD ($) shares | Dec. 20, 2022 USD ($) | Aug. 09, 2022 USD ($) | Jun. 01, 2022 USD ($) | Dec. 30, 2021 USD ($) Storagefacility | Dec. 31, 2024 USD ($) StorageFacility shares | Dec. 31, 2023 USD ($) | Dec. 31, 2022 USD ($) | Aug. 07, 2024 $ / shares | Jul. 31, 2024 USD ($) | Jul. 29, 2024 USD ($) | Jun. 30, 2024 | Nov. 01, 2023 $ / shares | Jan. 31, 2023 USD ($) | Aug. 29, 2022 USD ($) | Mar. 16, 2021 USD ($) | Mar. 10, 2021 USD ($)
Related Party Transaction [Line Items] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Payables to related parties |  |  |  |  |  |  |  |  |  |  |  |  | $ 11,000 |  |  |  |  |  |  |  |  |  |
Percentage of investment fee due upon closing |  |  |  |  |  |  | 1.00% |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Reimbursement of stock dividend |  |  |  | $ 6,600,000 |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Upfront sales commission |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  | 3.00% |  |  |  |
Upfront dealer manager |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  | 3.00% |  |  |  |
Organization and offering expense |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  | 1.00% |  |  |  |
Fully repayment of debt |  |  |  |  |  |  |  |  |  |  |  | $ 20,000,000 | 12,017,000 | $ 86,237,000 |  |  |  |  |  |  |  |  |
Number of self storage facilities |  |  |  |  |  |  |  |  |  |  | 2 | 161 |  |  |  |  |  |  |  |  |  |  |
Principal borrowing amount |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  | $ 500,000,000 |
Maturity Date Range, Start |  | Dec. 31, 2024 |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Maturity Date Range, End |  | Dec. 31, 2025 |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Other Income |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Related Party Transaction [Line Items] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Dividend distribution received |  |  |  |  |  |  |  |  |  |  |  | $ 300,000 | 300,000 |  |  |  |  |  |  |  |  |  |
SST VI |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Related Party Transaction [Line Items] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Payables to related parties |  |  |  |  |  |  |  |  |  |  |  | 200,000 |  |  |  |  |  |  |  |  |  |  |
Reimbursement of stock dividend |  |  |  |  |  |  |  |  |  |  |  | 9,300,000 |  |  |  |  |  |  |  |  |  |  |
Offering price | $ / shares |  |  |  |  |  |  |  |  |  |  |  |  |  |  | $ 10 |  |  |  | $ 10 |  |  |  |
Fully repayment of debt |  |  |  |  |  | $ 51,700,000 |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Debt instrument, description of variable rate basis |  |  |  |  | SOFR plus 3.0% |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Debt instrument, description of variable rate basis, extended |  | SOFR plus 4.0% |  |  | SOFR plus 4.0% |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Debt instrument, fee percentage |  |  |  |  | 0.25% |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Principal borrowing amount |  |  |  |  | $ 15,000,000 |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Commitment fee percentage |  |  |  |  | 1.00% |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Borrowing capacity |  | $ 25,000,000 |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Principal borrowing amount, currently available |  |  |  |  |  |  |  |  |  |  |  | $ 23,000 |  |  |  |  | $ 8,000,000 |  |  |  |  |  |
SST VI | Class Y and Class Z [Member] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Related Party Transaction [Line Items] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Offering price | $ / shares |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  | $ 9.3 |  |  |  |
SST VI | Maximum |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Related Party Transaction [Line Items] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Offering price | $ / shares |  |  |  |  |  |  |  |  |  |  |  |  |  |  | $ 10 |  |  |  |  |  |  |  |
SST VI Advisory Agreement |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Related Party Transaction [Line Items] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Rate of acquisition fees of purchase price of contract |  |  |  |  |  |  |  |  |  |  |  | 1.00% |  |  |  |  |  |  |  |  |  |  |
Monthly asset management fee |  |  |  |  |  |  |  |  |  |  |  | 0.0625% |  |  |  |  |  |  |  |  |  |  |
Monthly asset management fee one twelfth of less than one percentage of average invested assets |  |  |  |  |  |  |  |  |  |  |  | one-twelfth of 0.75 |  |  |  |  |  |  |  |  |  |  |
Commission percentage of contract sales price |  |  |  |  |  |  |  |  |  |  |  | 50.00% |  |  |  |  |  |  |  |  |  |  |
SST VI Advisory Agreement | Disposition Fee |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Related Party Transaction [Line Items] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Rate of disposition fee of contract sales price |  |  |  |  |  |  |  |  |  |  |  | 1.00% |  |  |  |  |  |  |  |  |  |  |
SST VI Advisory Agreement | Disposition Fee | Maximum |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Related Party Transaction [Line Items] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Rate of disposition fee of contract sales price |  |  |  |  |  |  |  |  |  |  |  | 6.00% |  |  |  |  |  |  |  |  |  |  |
Strategic Storage Growth Trust I I I Advisory Agreement |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Related Party Transaction [Line Items] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Rate of acquisition fees of purchase price of contract |  |  |  |  |  |  |  |  |  |  |  | 1.00% |  |  |  |  |  |  |  |  |  |  |
Monthly asset management fee |  |  |  |  |  |  |  |  |  |  |  | 0.0625% |  |  |  |  |  |  |  |  |  |  |
Monthly asset management fee one twelfth of less than one percentage of average invested assets |  |  |  |  |  |  |  |  |  |  |  | one-twelfth of 0.75 |  |  |  |  |  |  |  |  |  |  |
Strategic Storage Growth Trust I I I Advisory Agreement | Disposition Fee |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Related Party Transaction [Line Items] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Rate of disposition fee of contract sales price |  |  |  |  |  |  |  |  |  |  |  | 1.50% |  |  |  |  |  |  |  |  |  |  |
Strategic Storage Growth Trust I I I Advisory Agreement | Disposition Fee | Pacific Oak Holding Group |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Related Party Transaction [Line Items] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Rate of disposition fee of contract sales price |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  | 17.50% |  |  |  |  |
Administrative Services Agreement |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Related Party Transaction [Line Items] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Receivables due from related parties |  |  |  |  |  |  |  |  |  |  |  | $ 12,000 |  |  |  |  |  |  |  |  |  |  |
SST VI OP |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Related Party Transaction [Line Items] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Purchase units of limited partnership interest | shares |  |  |  |  |  |  | 600,000 |  |  |  |  | 1,000,000 |  |  |  |  |  |  |  |  |  |  |
Purchase commitment amount |  |  |  |  |  |  | $ 15,000,000 |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Description of preferred investor distributions |  |  |  |  |  |  | SmartStop, through its subsidiary, received distributions, payable monthly in arrears, at a rate of 7.0% per annum from the date of issuance until the second anniversary of the date of issuance, 8.0% per annum commencing thereafter until the third anniversary of the date of issuance, 9.0% per annum commencing thereafter until the fourth anniversary of the date of issuance, and 10% per annum thereafter, payable monthly. |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
SST VI OP | Up to Second Anniversary |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Related Party Transaction [Line Items] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Rate of distributions payable monthly in arrears |  |  |  |  |  |  | 7.00% |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
SST VI OP | Up to Third Anniversary |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Related Party Transaction [Line Items] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Rate of distributions payable monthly in arrears |  |  |  |  |  |  | 8.00% |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
SST VI OP | Up to Fourth Anniversary |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Related Party Transaction [Line Items] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Rate of distributions payable monthly in arrears |  |  |  |  |  |  | 9.00% |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
SST VI OP | Investment Thereafter |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Related Party Transaction [Line Items] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Rate of distributions payable monthly in arrears |  |  |  |  |  |  | 10.00% |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
SST VI OP | Other Income |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Related Party Transaction [Line Items] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Loss related to equity interest |  |  |  |  |  |  |  |  |  |  |  | $ 900,000 | 900,000 |  |  |  |  |  |  |  |  |  |
Property Management Agreement |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Related Party Transaction [Line Items] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Our former external property management fee |  |  |  |  |  |  |  |  |  |  |  | $ 3,000 |  |  |  |  |  |  |  |  |  |  |
Percentage of fee of former external property managers |  |  |  |  |  |  |  |  |  |  |  | 6.00% |  |  |  |  |  |  |  |  |  |  |
Construction management fee |  |  |  |  |  |  |  |  |  |  |  | 5.00% |  |  |  |  |  |  |  |  |  |  |
Cost of construction or capital improvement work |  |  |  |  |  |  |  |  |  |  |  | $ 10,000 |  |  |  |  |  |  |  |  |  |  |
One time fee for former external property managers |  |  |  |  |  |  |  |  |  |  |  | 3,750 |  |  |  |  |  |  |  |  |  |  |
Write-off of carrying value related to intangible asset |  |  |  |  |  |  |  |  |  | $ 600,000 |  |  |  |  |  |  |  |  |  |  |  |  |
Property Management Agreement | Other Income |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Related Party Transaction [Line Items] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Change in deferred tax liability |  |  |  |  |  |  |  |  |  |  |  |  |  | 200,000 |  |  |  |  |  |  |  |  |
SmartStop OP |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Related Party Transaction [Line Items] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Investment of preferred investor |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  | $ 5,000,000 |  |
Investment |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  | $ 5,000,000
SSGT III OP |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Related Party Transaction [Line Items] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Principal borrowing amount |  |  |  |  |  |  |  |  |  |  |  | 10,000,000 | 4,000,000 |  |  |  |  |  |  |  |  |  |
SSGT III OP | Other Income |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Related Party Transaction [Line Items] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Loss related to equity interest |  |  |  |  |  |  |  |  |  |  |  | 600,000 | 700,000 |  |  |  |  |  |  |  |  |  |
Dividend distribution received |  |  |  |  |  |  |  |  |  |  |  | $ 300,000 | $ 300,000 |  |  |  |  |  |  |  |  |  |
SST VI Mezzanine Loan |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Related Party Transaction [Line Items] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Outstanding amount |  |  |  |  |  |  |  |  |  |  |  |  |  | $ 35,000,000 |  |  |  |  |  | $ 15,000,000 |  |  |
Commitment fee percentage |  |  |  |  |  |  |  |  |  |  | 1.00% |  |  |  |  |  |  |  |  |  |  |  |
SST VI Mezzanine Loan | Minimum |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Related Party Transaction [Line Items] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Increased the principal borrowing amount |  |  |  |  |  |  |  | $ 45,000,000 |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
SST VI Mezzanine Loan | Maximum |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Related Party Transaction [Line Items] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Debt issued |  |  |  |  |  |  |  |  |  |  | $ 45,000,000 |  |  |  |  |  |  |  |  |  |  |  |
Increased the principal borrowing amount |  |  |  |  |  |  |  | $ 55,000,000 |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
SST VI Mezzanine Loan | Pacific Oak Holding Group |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Related Party Transaction [Line Items] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Debt instrument, description of variable rate basis |  |  |  |  |  |  |  | SOFR plus 3.0% |  |  | LIBOR plus 3.0% |  |  |  |  |  |  |  |  |  |  |  |
SSGT III Mezzanine Loan |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Related Party Transaction [Line Items] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Debt issued |  |  |  |  |  |  |  |  | $ 50,000,000 |  |  |  |  |  |  |  |  |  |  |  |  |  |
Fully repayment of debt |  |  | $ 1,000,000 |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Debt instrument, description of variable rate basis |  |  |  |  |  |  |  | SOFR plus 3.0% |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Line of credit facility, current borrowing capacity |  |  |  |  |  |  |  |  | $ 42,000,000 |  |  |  |  |  |  |  |  |  |  |  |  |  |
Commitment fee percentage |  |  |  |  |  |  |  |  | 1.00% |  |  |  |  |  |  |  |  |  |  |  |  |  |
SSGT III Mezzanine Loan | Upon Achievement Of Certain Financial Conditions |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Related Party Transaction [Line Items] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Debt instrument, description of variable rate basis |  |  |  |  |  |  |  | SOFR plus 4.0% |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
SSGT III Mezzanine Loan | Minimum |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Related Party Transaction [Line Items] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Increased the principal borrowing amount |  |  |  |  |  |  |  | $ 50,000,000 |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
SSGT III Mezzanine Loan | Maximum |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Related Party Transaction [Line Items] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Increased the principal borrowing amount |  |  |  |  |  |  |  | $ 77,000,000 |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
SSGT III Bridge Loan |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Related Party Transaction [Line Items] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Principal borrowing amount |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  | $ 20,000,000 |  |  |  |  |  |  |
Line of credit facility, Frequency of payments |  |  |  |  |  |  |  |  |  |  |  | SSGT III will be required to pay down at least 15% of the balance within four months, 35% within six months, 55% within nine months, and 75% within twelve months from the final draw |  |  |  |  |  |  |  |  |  |  |
Net proceeds to pay down within four months |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  | 15.00% |  |  |  |  |  |  |
Net proceeds to pay down within six months |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  | 35.00% |  |  |  |  |  |  |
Net proceeds to pay down within nine months |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  | 55.00% |  |  |  |  |  |  |
Net proceeds to pay down within twelve months |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  | 75.00% |  |  |  |  |  |  |
Repayment of borrowings |  |  |  |  |  |  |  |  |  |  |  | $ 17,000,000 |  |  |  |  |  |  |  |  |  |  |
Amount outstanding |  |  |  |  |  |  |  |  |  |  |  | $ 2,900,000 |  |  |  |  |  |  |  |  |  |  |
SSGT III Promissory Note |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Related Party Transaction [Line Items] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Debt issued | $ 7,000,000 |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Debt instrument, description of variable rate basis | SOFR plus 3.0% |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Commitment fee percentage | 0.50% |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |

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