Summary of Total Assets by Segment (Parenthetical) (Detail) - USD ($)
Sep. 30, 2020
Dec. 31, 2019
Jun. 28, 2019
Segment Reporting Asset Reconciling Item [Line Items]      
Goodwill $ 53,643,331 $ 78,372,980 $ 78,372,980
Self Storage      
Segment Reporting Asset Reconciling Item [Line Items]      
Goodwill 45,300,000    
Managed REIT Platform      
Segment Reporting Asset Reconciling Item [Line Items]      
Goodwill $ 8,400,000