v3.25.3
Real Estate - Additional Information (Detail)
$ in Millions
1 Months Ended 3 Months Ended 9 Months Ended
Nov. 07, 2025
USD ($)
StorageFacility
Site
Oct. 31, 2025
StorageProperty
Sep. 03, 2025
USD ($)
Aug. 26, 2025
USD ($)
Property
Aug. 26, 2025
CAD ($)
Property
Jun. 17, 2025
USD ($)
Property
May 29, 2025
USD ($)
Apr. 15, 2025
USD ($)
Feb. 20, 2025
USD ($)
Jan. 07, 2025
USD ($)
May 31, 2025
StorageProperty
Sep. 30, 2025
USD ($)
ft²
Sep. 30, 2024
USD ($)
Sep. 30, 2025
USD ($)
ft²
StorageFacility
Sep. 30, 2024
USD ($)
Apr. 15, 2025
CAD ($)
Business Acquisition [Line Items]                                
Total net rentable | ft²                       115,000   115,000    
Carrying value of properties                       $ 15,900,000   $ 15,900,000    
Impairment losses of real property assets recognized                           0    
Segment operating income                       42,869,000 $ 38,999,000 124,473,000 $ 115,465,000  
Number of self storage facilities | StorageProperty                     2          
Number of self storage facilities purchased | StorageProperty   5                            
Asheville III                                
Business Acquisition [Line Items]                                
Segment operating income                           800,000    
Asheville IV                                
Business Acquisition [Line Items]                                
Segment operating income                           700,000    
Self Storage [Member]                                
Business Acquisition [Line Items]                                
Segment operating income                       $ 41,102,000 $ 37,129,000 $ 119,042,000 $ 109,689,000  
Managed REITs                                
Business Acquisition [Line Items]                                
Total net rentable | ft²                       4,400,000   4,400,000    
Number of self storage facilities | StorageFacility                           40,000    
Houston, Texas                                
Business Acquisition [Line Items]                                
Number of self storage facilities | Property           1                    
Number of self storage facilities purchased | Property           5                    
Alberta, Canada                                
Business Acquisition [Line Items]                                
Number of self storage facilities purchased | Property       5 5                      
Subsequent Event                                
Business Acquisition [Line Items]                                
Number of development real estate properties | Site 4                              
Self Storage Facilities | Hillside, New Jersey                                
Business Acquisition [Line Items]                                
Consideration transferred                   $ 35,900,000            
Self Storage Facilities | Clifton, New Jersey                                
Business Acquisition [Line Items]                                
Consideration transferred                   $ 38,600,000            
Self Storage Facilities | Murfreesboro, Tennessee                                
Business Acquisition [Line Items]                                
Consideration transferred                 $ 7,900,000              
Self Storage Facilities | Kelowna, British Columbia                                
Business Acquisition [Line Items]                                
Consideration transferred               $ 29,100,000                
Loan amount               $ 17,700,000               $ 24.5
Self Storage Facilities | Lakewood, Colorado                                
Business Acquisition [Line Items]                                
Consideration transferred             $ 12,700,000                  
Self Storage Facilities | Houston, Texas                                
Business Acquisition [Line Items]                                
Consideration transferred           $ 108,100,000                    
Loan amount           $ 8,800,000                    
Self Storage Facilities | Alberta, Canada                                
Business Acquisition [Line Items]                                
Consideration transferred       $ 70,300,000 $ 97.4                      
Self Storage Facilities | Rahway, New Jersey                                
Business Acquisition [Line Items]                                
Consideration transferred     $ 15,300,000                          
Self Storage Facilities | Subsequent Event                                
Business Acquisition [Line Items]                                
Consideration transferred $ 43,400,000                              
Forfeit earnest money $ 700,000                              
Number of self storage facilities | StorageFacility 3                              
Number of self storage facilities purchased | StorageFacility 5