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Organization - Additional Information (Detail) |  |  |  |  |  |  |  |  |  | 1 Months Ended | 3 Months Ended | 9 Months Ended | 12 Months Ended |  |
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Dec. 06, 2022 $ / shares | Jun. 01, 2022 ft² RealEstateVenture State StorageFacility StorageUnit shares | Apr. 19, 2022 USD ($) | Dec. 30, 2021 StorageFacility | Oct. 07, 2021 USD ($) | Mar. 17, 2021 StorageFacility shares | Mar. 17, 2021 StorageFacility | Mar. 17, 2021 StorageFacility StorageUnit | Mar. 17, 2021 RealEstateVenture StorageFacility | Mar. 17, 2021 USD ($) StorageFacility | Mar. 17, 2021 StorageFacility REALESTATEVENTURE | Nov. 10, 2020 State REALESTATEVENTURE StorageFacility | Jan. 31, 2014 USD ($) | Aug. 02, 2013 USD ($) | Jan. 31, 2017 USD ($) shares | Sep. 30, 2023 USD ($) ft² REALESTATEVENTURE State shares | Jun. 30, 2023 shares | Jun. 30, 2022 shares | Mar. 31, 2022 shares | Sep. 30, 2023 USD ($) ft² Property StorageFacility REALESTATEVENTURE StorageUnit State shares | Dec. 31, 2022 USD ($) ft² Property StorageUnit REALESTATEVENTURE StorageFacility State shares | Dec. 31, 2021 shares | Dec. 31, 2020 shares | Mar. 17, 2021 State | Mar. 17, 2021 ft² | Mar. 17, 2021 | Mar. 17, 2021 USD ($) | Mar. 17, 2021 STORAGEPROPERTY | Nov. 30, 2016 USD ($) shares
Organization And Nature Of Operations [Line Items] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Date of formation of company |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  | Jan. 08, 2013 | Jan. 08, 2013 |  |  |  |  |  |  |  |  |
Number of self storage facilities | StorageFacility |  |  |  | 2 |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  | 154 | 153 |  |  |  |  |  |  |  |  |
Number of states located for self storage facilities | State |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  | 19 |  |  |  | 19 | 19 |  |  |  |  |  |  |  |  |
Shares issuable pursuant to distribution reinvestment plan |  |  |  |  |  |  |  |  |  |  |  |  | $ 95,000,000 |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Advisor, SS Toronto REIT Advisors, Inc., and SS Growth Advisor, LLC. |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Organization And Nature Of Operations [Line Items] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Interests |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  | 88.30% |  |  |  | 88.30% | 88.40% |  |  |  |  |  |  |  |  |
SAM and Affiliates |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Organization And Nature Of Operations [Line Items] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Percentage of limited partnership interests owned by noncontrolling owners |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  | 11.70% |  |  |  | 11.70% | 11.60% |  |  |  |  |  |  |  |  |
Strategic Storage Operating Partnership II, L.P. |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Organization And Nature Of Operations [Line Items] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Date of formation of company |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  | Jan. 09, 2013 |  |  |  |  |  |  |  |  |
Advisor purchased a limited partnership interest in Operating Partnership |  |  |  |  |  |  |  |  |  |  |  |  |  | $ 200,000 |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Initial capital contribution |  |  |  |  |  |  |  |  |  |  |  |  |  | $ 1,000 |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Distribution Reinvestment Plan |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Organization And Nature Of Operations [Line Items] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Common stock, value authorize |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  | $ 100,900,000
Common Stock, shares authorize | shares |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  | 100,900,000
Description for termination of offering |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  | The DRP Offering may be terminated at any time upon 10 days’ prior written notice to stockholders. | The DRP Offering may be terminated at any time upon 10 days’ prior written notice to stockholders. |  |  |  |  |  |  |  |  |
Primary Offering |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Organization And Nature Of Operations [Line Items] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Initial public offering commenced period description |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  | We commenced our initial public offering in January 2014 | We commenced our initial public offering in January 2014 |  |  |  |  |  |  |  |  |
Maximum | Primary Offering |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Organization And Nature Of Operations [Line Items] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Common stock, value authorize |  |  |  |  |  |  |  |  |  |  |  |  | $ 1,000,000,000 |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Key Bank [Member] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Organization And Nature Of Operations [Line Items] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Outstanding balance on credit facility |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  | $ 500,000,000 |  |
Proceeds from line of credit |  |  |  |  |  |  |  |  |  | $ 451,000,000 |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Credit Facility Revolver |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Organization And Nature Of Operations [Line Items] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Credit facility, increased commitment |  |  |  |  | $ 200,000,000 |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Credit facility, aggregate commitment |  |  |  |  | 450,000,000 |  |  |  |  |  |  |  |  |  |  | $ 450,000,000 |  |  |  | $ 450,000,000 | $ 450,000,000 |  |  |  |  |  |  |  |  |
Credit Facility Revolver | Key Bank [Member] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Organization And Nature Of Operations [Line Items] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Outstanding balance on credit facility |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  | 250,000,000 |  |
Credit facility, aggregate commitment |  |  |  |  | 700,000,000 |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Credit Facility Revolver | Key Bank [Member] | Minimum |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Organization And Nature Of Operations [Line Items] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Credit facility, increased commitment |  |  |  |  | 200,000,000 |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Credit Facility Revolver | Key Bank [Member] | Maximum |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Organization And Nature Of Operations [Line Items] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Credit facility, increased commitment |  |  |  |  | $ 450,000,000 |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Credit Facility Term Loan |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Organization And Nature Of Operations [Line Items] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Credit facility, aggregate commitment |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  | $ 250,000,000 |  |  |  | $ 250,000,000 | $ 250,000,000 |  |  |  |  |  |  |  |  |
Credit Facility Term Loan | Key Bank [Member] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Organization And Nature Of Operations [Line Items] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Outstanding balance on credit facility |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  | $ 250,000,000 |  |
2032 Private Placement Notes |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Organization And Nature Of Operations [Line Items] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Debt instrument, maturity date |  |  | Apr. 19, 2032 |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  | Apr. 19, 2032 | Apr. 19, 2032 | [1] |  |  |  |  |  |  |  |
Class A Common stock |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Organization And Nature Of Operations [Line Items] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Common Stock, shares authorize | shares |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  | 350,000,000 |  |  |  | 350,000,000 | 350,000,000 |  | 350,000,000 |  |  |  |  |  |  |
Estimated value per common share | $ / shares | $ 15.21 |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Class A Common stock | Distribution Reinvestment Plan |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Organization And Nature Of Operations [Line Items] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Stock Issued During Period, Shares, Dividend Reinvestment Plan | shares |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  | 7,900,000 |  |  |  |  |  |  |  |  |  |
Class A Common stock | Common Stock |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Organization And Nature Of Operations [Line Items] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Issuance of common stock in connection with SST IV Merger (in shares) | shares |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  | 11,542,062 |  |  | 11,542,062 |  | 23,137,540 |  |  |  |  |  |  |
Stock Issued During Period, Shares, Dividend Reinvestment Plan | shares |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  | 348,984 | 353,648 |  | 313,658 |  | 313,658 |  | 1,541,585 | 1,318,605 |  |  |  |  |  |
Class A Common stock | Common Stock | Distribution Reinvestment Plan |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Organization And Nature Of Operations [Line Items] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Gross proceeds from issuance of common stock |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  | $ 77,800,000 |  |  |  |  |  |  |  |  |
Number of common stock issued | shares |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  | 7,200,000 |  |  |  |  |  |  |  |  |
Class A Common stock | Common Stock | Primary Offering |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Organization And Nature Of Operations [Line Items] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Number of shares issued in offering | shares |  |  |  |  |  |  |  |  |  |  |  |  |  |  | 48,000,000 |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Gross proceeds from issuance of common stock |  |  |  |  |  |  |  |  |  |  |  |  |  |  | $ 493,000,000 |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Class A Common stock | 2032 Private Placement Notes |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Organization And Nature Of Operations [Line Items] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Debt issued |  |  | $ 150,000,000 |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Debt Instrument Fixed Rate |  |  | 4.53% |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Class T Common stock |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Organization And Nature Of Operations [Line Items] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Common Stock, shares authorize | shares |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  | 350,000,000 |  |  |  | 350,000,000 | 350,000,000 |  | 350,000,000 |  |  |  |  |  |  |
Estimated value per common share | $ / shares | $ 15.21 |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Class T Common stock | Distribution Reinvestment Plan |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Organization And Nature Of Operations [Line Items] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Stock Issued During Period, Shares, Dividend Reinvestment Plan | shares |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  | 1,100,000 |  |  |  |  |  |  |  |  |  |
Class T Common stock | Common Stock |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Organization And Nature Of Operations [Line Items] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Stock Issued During Period, Shares, Dividend Reinvestment Plan | shares |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  | 39,233 | 38,871 |  | 34,048 |  | 34,048 |  | 182,445 | 204,018 |  |  |  |  |  |
Class T Common stock | Common Stock | Distribution Reinvestment Plan |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Organization And Nature Of Operations [Line Items] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Gross proceeds from issuance of common stock |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  | $ 11,100,000 |  |  |  |  |  |  |  |  |
Number of common stock issued | shares |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  | 1,000,000 |  |  |  |  |  |  |  |  |
Class T Common stock | Common Stock | Primary Offering |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Organization And Nature Of Operations [Line Items] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Number of shares issued in offering | shares |  |  |  |  |  |  |  |  |  |  |  |  |  |  | 7,000,000 |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Gross proceeds from issuance of common stock |  |  |  |  |  |  |  |  |  |  |  |  |  |  | $ 73,000,000 |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Canada |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Organization And Nature Of Operations [Line Items] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Number of self storage units | RealEstateVenture |  | 7,740 |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
SSGT II Merger Agreement |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Organization And Nature Of Operations [Line Items] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Number of self storage facilities | StorageFacility |  | 10 |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Number of states located for self storage facilities | State |  | 7 |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Number of self storage units | StorageUnit |  | 7,740 |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Net rentable area, primarily self storage space | ft² |  | 853,900 |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Percentage of membership interest |  | 50.00% |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Number of unconsolidated real estate ventures | RealEstateVenture |  | 3 |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Number of operating self storage facilities | Property |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  | 1 |  |  |  |  |  |  |  |  |
SSGT II Merger Agreement | Class A Common stock |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Organization And Nature Of Operations [Line Items] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Issuance of common stock in connection with SST IV Merger (in shares) | shares |  | 11,500,000 |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Number of shares exchanged in connection with merger | shares |  | 12,700,000 |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
SSGT II Merger Agreement | Canada |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Organization And Nature Of Operations [Line Items] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Number of operating self storage facilities | REALESTATEVENTURE |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  | 2 |  |  |  | 2 | 1 |  |  |  |  |  |  |  |  |
Number of parcels of land being developed into self storage facilities | REALESTATEVENTURE |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  | 1 |  |  |  | 1 | 2 |  |  |  |  |  |  |  |  |
SST IV Merger Agreement |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Organization And Nature Of Operations [Line Items] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Number of self storage facilities | StorageFacility |  |  |  |  |  |  | 24 |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Number of states located for self storage facilities | State |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  | 9 |  |  |  |  |
Number of self storage units | StorageUnit |  |  |  |  |  |  |  | 18,000 |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Net rentable area, primarily self storage space | ft² |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  | 2,000,000 |  |  |  |
Percentage of membership interest |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  | 50.00% |  |  |
Number of operating self storage facilities | Property |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  | 2 |  |  |  |  |  |  |  |  |
SST IV Merger Agreement | SST IV Common Stock |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Organization And Nature Of Operations [Line Items] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Number of shares exchanged in connection with merger | shares |  |  |  |  |  | 10,600,000 |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
SST IV Merger Agreement | Class A Common stock |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Organization And Nature Of Operations [Line Items] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Issuance of common stock in connection with SST IV Merger (in shares) | shares |  |  |  |  |  | 23,100,000 |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
SST IV Merger Agreement | Canada |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Organization And Nature Of Operations [Line Items] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Number of self storage facilities | StorageFacility |  |  |  |  |  |  |  |  |  |  |  | 24 |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Number of states located for self storage facilities | State |  |  |  |  |  |  |  |  |  |  |  | 9 |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Number of unconsolidated real estate ventures |  |  |  |  |  |  |  |  | 6 |  | 6 |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Number of operating self storage facilities |  |  |  |  |  | 3 | 3 | 3 | 3 | 3 | 3 | 3 |  |  |  |  |  |  |  |  | 5 |  |  |  |  |  |  |  | 3 |
Number of parcels of land being developed into self storage facilities |  |  |  |  |  | 3 | 3 | 3 | 3 | 3 | 3 | 3 |  |  |  |  |  |  |  |  | 1 |  |  |  |  |  |  |  | 3 |
Managed REITS |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Organization And Nature Of Operations [Line Items] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Number of properties owned by Managed REITs which is operated by the company | Property |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  | 31 | 19 |  |  |  |  |  |  |  |  |
Number of self storage units | StorageUnit |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  | 25,000 | 14,600 |  |  |  |  |  |  |  |  |
Net rentable area, primarily self storage space | ft² |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  | 2,800,000 |  |  |  | 2,800,000 | 1,800,000 |  |  |  |  |  |  |  |  |
SmartStop Asset Management |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Organization And Nature Of Operations [Line Items] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Percentage of non-voting equity owned |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  | 15.00% |  |  |  |  |  |  |  |  |
SmartStop Asset Management | Investments in Majority-owned Subsidiaries |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Organization And Nature Of Operations [Line Items] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Percentage of non-voting equity owned |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  | 15.00% |  |  |  |  |  |  |  |  |
[1] | For additional information regarding this loan, see below

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