Quarterly report pursuant to Section 13 or 15(d)

RELATED PARTY TRANSACTIONS (Details)

v3.21.1
RELATED PARTY TRANSACTIONS (Details)
$ in Thousands
3 Months Ended
Mar. 31, 2021
USD ($)
property
shares
Mar. 31, 2020
USD ($)
property
Related Party Transaction [Line Items]    
Payroll and related costs reimbursed to the PROs by the Company $ 34,604 $ 30,592
Number of properties acquired | property 23 23
Consideration in acquisition transaction   $ 165,963
Value of OP Equity   22,897
Supervisory and Administrative Fee Agreement | Management | Participating Regional Operator (PRO)    
Related Party Transaction [Line Items]    
Supervisory and administrative fees paid to the PROs $ 4,200 5,300
Supervisory and Administrative Fee Agreement | Management | Participating Regional Operator (PRO) | Minimum    
Related Party Transaction [Line Items]    
Supervisory and administrative fee agreement of gross revenue, percent 5.00%  
Supervisory and Administrative Fee Agreement | Management | Participating Regional Operator (PRO) | Maximum    
Related Party Transaction [Line Items]    
Supervisory and administrative fee agreement of gross revenue, percent 6.00%  
Payroll Services | Management | Participating Regional Operator (PRO)    
Related Party Transaction [Line Items]    
Payroll and related costs reimbursed to the PROs by the Company $ 6,400 8,800
Due Diligence Costs | Management | Participating Regional Operator (PRO)    
Related Party Transaction [Line Items]    
Due diligence expenses payable to the PROs $ 300 $ 200
Self storage property purchase from affiliate of trustee | Affiliated entity    
Related Party Transaction [Line Items]    
Number of properties acquired | property 1  
Consideration in acquisition transaction $ 8,800  
OP units | Self storage property purchase from affiliate of trustee | Affiliated entity | Mr. J. Timothy Warren    
Related Party Transaction [Line Items]    
Number of OP Units in acquisition (in shares) | shares 29,123  
Value of OP Equity $ 1,100