Real Estate Facilities - Additional Information (Detail)
$ in Millions
Sep. 01, 2020
CAD ($)
Jul. 21, 2020
USD ($)
ft²
StorageFacility
Jun. 02, 2020
CAD ($)
Oct. 01, 2018
USD ($)
StorageFacility
State
shares
Sep. 30, 2020
State
Jan. 24, 2019
USD ($)
Restructuring Cost And Reserve [Line Items]            
Repayment of debt           $ 141,088,724
Principal borrowing           500,178,000
Number of operating self storage facilities | StorageFacility       28    
Number of states for self storage facilities | State       10 17  
Number of operating self storage facilities | StorageFacility       1    
SS Growth Advisor LLC | Capital Unit, Class A            
Restructuring Cost And Reserve [Line Items]            
Business acquisition partnership units issued | shares       396,000    
Etobicoke Property            
Restructuring Cost And Reserve [Line Items]            
Purchase price     $ 2.2      
Scarborough Property            
Restructuring Cost And Reserve [Line Items]            
Purchase price $ 2.2          
Acquisition of Self Storage Facility | Riverview, Florida            
Restructuring Cost And Reserve [Line Items]            
Purchase price   $ 800,000        
Number of units added to existing self storage facility | StorageFacility   170        
Rentable area added to existing self storage facility | ft²   25,000        
Strategic Storage Growth Trust, Inc            
Restructuring Cost And Reserve [Line Items]            
Purchase price       $ 350,448,960    
Repayment of debt           141,000,000
Principal borrowing           $ 500,000,000
SS Growth Operating Partnership, L.P            
Restructuring Cost And Reserve [Line Items]            
Limited partners' capital account, units converted in to percentage       112.70%