Summary of Significant Accounting Policies - Additional Information (Detail)
shares in Millions
 12 Months Ended
Dec. 31, 2021
USD ($)
Segment
Trademark
shares
Dec. 31, 2020
USD ($)
shares
Dec. 31, 2019
USD ($)
shares
Jun. 28, 2019
USD ($)
Summary Of Significant Accounting Policies [Line Items]        
Investments in Managed REITs       $ 5,600,000
Payments to acquire intangible assets $ 21,500,000 $ 0 $ 13,600,000  
Business acquisition, transaction costs 900,000 1,400,000 200,000  
Impairment losses of real property assets recognized 0 0 0  
Trademarks acquired $ 16,052,941 16,194,118    
Number of trademarks acquired | Trademark 2      
Amortization period of intangible assets 18 months      
Gross amounts of lease intangibles $ 68,600,000 47,300,000    
Accumulated amortization 56,800,000 45,700,000    
Redemptions of common stock $ 5,600,000 $ 2,000,000.0 $ 4,900,000  
Redemptions of common stock (in shares) | shares 0.4 0.2 0.5  
Maximum annual contributions per employee, percentage 100.00%      
Employer matching contributions, amount $ 0.2      
Employer matching contribution, percent 100.00%      
Employer matching contribution, percent of match 4.00%      
Net deferred tax liability $ 7,719,098 $ 8,380,215    
Deferred tax benefit $ 2,000,000.0 5,900,000    
Minimum percentage of ordinary taxable income to be distributed to stockholders 90.00%      
Current income tax expense $ 200,000 100,000    
Net combined foreign, federal, and state income tax benefit 1,800,000 5,800,000    
Unrecognized tax benefits $ 3,700,000 4,100,000    
Open tax year 2017 2018 2019 2020      
Number of reportable business segments | Segment 2      
Allowance for doubtful accounts $ 500,000 300,000    
Operating Expense        
Summary Of Significant Accounting Policies [Line Items]        
Advertising costs 3,700,000 2,900,000    
General and Administrative Expense        
Summary Of Significant Accounting Policies [Line Items]        
Advertising costs $ 800,000 600,000 $ 700,000  
Rental Income | Geographic Concentration Risk | Florida        
Summary Of Significant Accounting Policies [Line Items]        
Concentration Risk Percentage1 22.00%      
Rental Income | Geographic Concentration Risk | California        
Summary Of Significant Accounting Policies [Line Items]        
Concentration Risk Percentage1 21.00%      
Rental Income | Geographic Concentration Risk | Greater Toronto Area of Canada        
Summary Of Significant Accounting Policies [Line Items]        
Concentration Risk Percentage1 11.00%      
Canadian Entities        
Summary Of Significant Accounting Policies [Line Items]        
Net deferred tax liability $ 7,100,000 5,800,000    
Gross deferred tax liability 10,200,000 9,600,000    
Gross deferred tax asset 3,100,000 3,800,000    
Real Estate Investment        
Summary Of Significant Accounting Policies [Line Items]        
Gains (losses) on exchange rate changes in equity investments recorded in other income (expense) $ 3,800,000 600,000    
Class T Common stock        
Summary Of Significant Accounting Policies [Line Items]        
Monthly stockholder servicing fee accrual description accrues daily in an amount equal to 1/365th of 1% of the purchase price per share      
Redeemable Common Stock        
Summary Of Significant Accounting Policies [Line Items]        
Redemptions of common stock $ 1,700,000 700,000 400,000  
Redeemable Common Stock | Share Redemption Program        
Summary Of Significant Accounting Policies [Line Items]        
Redemptions of common stock 3,900,000 1,300,000 $ 4,500,000  
Revolving Credit Facility        
Summary Of Significant Accounting Policies [Line Items]        
Debt issuance cost, gross 4,100,000 0    
Accumulated amortization of debt issuance costs 800,000 0    
Non Revolving Debt        
Summary Of Significant Accounting Policies [Line Items]        
Debt issuance cost, gross 5,800,000 12,000,000.0    
Accumulated amortization of debt issuance costs 1,900,000 7,900,000    
Self Storage        
Summary Of Significant Accounting Policies [Line Items]        
Total estimated future amortization expense of intangible assets, year 2022 10,500,000      
Total estimated future amortization expense of intangible assets, year 2023 200,000      
Total estimated future amortization expense of intangible assets, year 2024 100,000      
Total estimated future amortization expense of intangible assets, year 2025 100,000      
Total estimated future amortization expense of intangible assets, thereafter $ 1,000,000.0      
Minimum        
Summary Of Significant Accounting Policies [Line Items]        
Estimated useful life 3 years      
Maximum        
Summary Of Significant Accounting Policies [Line Items]        
Estimated useful life 5 years      
Strategic Storage Trademark        
Summary Of Significant Accounting Policies [Line Items]        
Trademarks acquired amount $ 400,000 500,000    
Trademarks acquired 15,700,000      
Total estimated future amortization expense of intangible assets, year 2022 140,000      
Total estimated future amortization expense of intangible assets, year 2023 140,000      
Total estimated future amortization expense of intangible assets, year 2024 70,000      
Total estimated future amortization expense of intangible assets, thereafter 0      
Self Administration Transaction        
Summary Of Significant Accounting Policies [Line Items]        
Total estimated future amortization expense of intangible assets, year 2022 700,000      
Total estimated future amortization expense of intangible assets, year 2023 700,000      
Total estimated future amortization expense of intangible assets, year 2024 700,000      
Total estimated future amortization expense of intangible assets, year 2025 300,000      
Total estimated future amortization expense of intangible assets, thereafter 0      
Gross amounts of lease intangibles 6,800,000 18,100,000    
Accumulated amortization 4,300,000 7,300,000    
Deferred tax liability on intangible assets acquired $ 600,000 2,600,000    
Primary Offering Former Dealer Manager Agreement | Class A Common stock        
Summary Of Significant Accounting Policies [Line Items]        
Percentage of gross proceeds from sale of shares 10.00%      
Investments in and Advances to Managed REITs        
Summary Of Significant Accounting Policies [Line Items]        
Investments in Managed REITs $ 11,000,000.0 15,100,000    
Investments in and Advances to Managed REITs | Managed REITs        
Summary Of Significant Accounting Policies [Line Items]        
Receivables due from related parties $ 1,400,000 $ 500,000