v3.25.4
Organization - Additional Information (Detail)
$ / shares in Units, $ in Thousands
 1 Months Ended 12 Months Ended
Jul. 30, 2025
USD ($)
$ / shares
shares
May 01, 2025
shares
Apr. 03, 2025
USD ($)
shares
Apr. 01, 2025
$ / shares
shares
Apr. 19, 2022
shares
May 31, 2025
StorageProperty
Apr. 30, 2025
shares
Dec. 31, 2025
ft²
State
StorageUnit
Property
StorageFacility
$ / shares
shares
Dec. 31, 2024
USD ($)
Property
$ / shares
shares
Dec. 31, 2023
USD ($)
$ / shares
Jun. 12, 2025
$ / shares
shares
Mar. 20, 2025
$ / shares
shares
May 14, 2024
shares
Nov. 30, 2016
USD ($)
Organization And Nature Of Operations [Line Items]                            
Date of formation of company               Jan. 08, 2013            
Number of real estate properties | Property                 1          
Number of self storage facilities | StorageProperty           2                
Number of states located for self storage facilities | State               19            
Net rentable area, primarily self storage space | ft²               115,000            
Redemptions of common stock, value | $ $ 300               $ 2 $ 1        
Redemptions of common stock (in shares) 8,000                          
Redemption of common stock, purchase price | $ / shares $ 35.63                          
Common Stock, shares authorized               141,250,000 0   175,000,000      
Common Stock, par value | $ / shares               $ 0.001 $ 0.001   $ 0.001      
Common stock shares without designation, authorized                     141,250,000      
Preferred stock, authorized                     50,000,000      
Preferred stock, authorized, par value | $ / shares                     $ 0.001      
Advisor, SS Toronto REIT Advisors, Inc., and SS Growth Advisor, LLC.                            
Organization And Nature Of Operations [Line Items]                            
Percentage of limited partnership interests               94.00%            
SAM and Affiliates                            
Organization And Nature Of Operations [Line Items]                            
Percentage of Joint venture minority ownership               6.00%            
Distribution Reinvestment Plan                            
Organization And Nature Of Operations [Line Items]                            
Common stock, value authorize | $                           $ 100,900
Underwritten Public Offering [Member]                            
Organization And Nature Of Operations [Line Items]                            
Initial price | $ / shares       $ 30                    
Common Stock, par value | $ / shares       $ 0.001                    
Number of shares issued in offering       27,000,000 27,000,000                  
Gross proceeds from issuance of common stock | $     $ 931,500                      
Net proceeds from issuance of common stock | $     $ 875,600                      
Underwritten Public Offering [Member] | Officers and Directors                            
Organization And Nature Of Operations [Line Items]                            
Number of shares issued in offering             31,500              
Over-Allotment Option [Member]                            
Organization And Nature Of Operations [Line Items]                            
Number of shares issued in offering     4,050,000                      
Minimum [Member]                            
Organization And Nature Of Operations [Line Items]                            
Common Stock, shares authorized                     900,000,000      
Maximum [Member]                            
Organization And Nature Of Operations [Line Items]                            
Common Stock, shares authorized                     225,000,000      
Class A Common stock                            
Organization And Nature Of Operations [Line Items]                            
Common Stock, shares authorized               31,250,000 350,000,000   31,250,000 225,000,000    
Common Stock, par value | $ / shares               $ 0.001 $ 0.001     $ 0.001    
Class A Common stock | Distribution Reinvestment Plan                            
Organization And Nature Of Operations [Line Items]                            
Common Stock, shares authorized                         1,125,000  
Number of shares issued in offering   2,700,000                        
Class T Common stock                            
Organization And Nature Of Operations [Line Items]                            
Common Stock, shares authorized               2,500,000 350,000,000   2,500,000 340,000,000    
Common Stock, par value | $ / shares                 $ 0.001 $ 0.001   $ 0.001    
Class T Common stock | Distribution Reinvestment Plan                            
Organization And Nature Of Operations [Line Items]                            
Common Stock, shares authorized                         125,000  
Number of shares issued in offering   300,000                        
Class A and Class T Common Stock                            
Organization And Nature Of Operations [Line Items]                            
Common Stock, shares authorized                       565,000,000    
Common Stock, par value | $ / shares               $ 0.001            
Self Storage Facility                            
Organization And Nature Of Operations [Line Items]                            
Number of self storage facilities | StorageFacility               122,000            
Net rentable area, primarily self storage space | ft²               13,900,000            
Managed REITs                            
Organization And Nature Of Operations [Line Items]                            
Number of self storage facilities | StorageFacility               41,000            
Number of properties owned by Managed REITs which is operated by the company | Property               52            
Number of self storage units | StorageUnit               177            
Net rentable area, primarily self storage space | ft²               4,500,000            
Argus Professional Storage Management LLC                            
Organization And Nature Of Operations [Line Items]                            
Number of self storage facilities | StorageFacility               98,000            
Number of properties owned by Managed REITs which is operated by the company | Property               221            
Net rentable area, primarily self storage space | ft²               15,900,000            
Managed Platform                            
Organization And Nature Of Operations [Line Items]                            
Number of self storage facilities | StorageFacility               140,000            
Number of self storage units | StorageUnit               273            
Net rentable area, primarily self storage space | ft²               20,400,000            
Canada                            
Organization And Nature Of Operations [Line Items]                            
Number of unconsolidated real estate ventures | StorageUnit               13            
Number of real estate properties | StorageUnit               3            
Number of self storage units | StorageUnit               10            
Canada | Advisor, SS Toronto REIT Advisors, Inc., and SS Growth Advisor, LLC.                            
Organization And Nature Of Operations [Line Items]                            
Percentage of limited partnership interests               50.00%