Quarterly report pursuant to Section 13 or 15(d)

RELATED PARTY TRANSACTIONS (Details)

v3.10.0.1
RELATED PARTY TRANSACTIONS (Details) - USD ($)
$ in Thousands
3 Months Ended 6 Months Ended
Jun. 30, 2018
Jun. 30, 2017
Jun. 30, 2018
Jun. 30, 2017
Related Party Transaction [Line Items]        
Payroll and related costs reimbursed to the PROs by the Company $ 25,184 $ 19,803 $ 50,410 $ 39,552
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 3,500 $ 8,200 6,800
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 7,200 5,900 $ 14,500 11,700
Due Diligence Costs | Management | Participating Regional Operator (PRO)        
Related Party Transaction [Line Items]        
Due diligence expenses payable to the PROs $ 100 $ 200 300 $ 300
NSA OP, LP | Affiliated Entity        
Related Party Transaction [Line Items]        
Value of co-investment in acquisition     $ 300  
Subordinated performance units | NSA OP, LP | Affiliated Entity        
Related Party Transaction [Line Items]        
Subordinated performance units issued to an affiliate of Personal Mini     11,490