Quarterly report pursuant to Section 13 or 15(d)

ORGANIZATION AND NATURE OF OPERATIONS (Details)

v3.2.0.727
ORGANIZATION AND NATURE OF OPERATIONS (Details)
$ / shares in Units, storage_unit in Thousands, $ in Thousands, ft² in Millions
6 Months Ended
May. 18, 2015
USD ($)
shares
Apr. 28, 2015
$ / shares
shares
Jun. 30, 2015
USD ($)
ft²
storage_unit
regional_operator
state
property
$ / shares
shares
Jun. 30, 2014
USD ($)
Subsidiary of Limited Liability Company or Limited Partnership [Line Items]        
Net proceeds from issuance of common shares in IPO | $     $ 278,070 $ 0
Number of self storage properties owned | property     246  
Number of states that self storage properties are owned in | state     16  
Total rentable square feet in self storage properties | ft²     13.6  
Number of storage units owned | storage_unit     107  
Number of participating regional operators | regional_operator     6  
National Storage Affiliates Holdings LLC [Member] | National Storage Affiliates Trust [Member]        
Subsidiary of Limited Liability Company or Limited Partnership [Line Items]        
Percentage of NSA owned by NSA Holdings prior to IPO     100.00%  
National Storage Affiliates Holdings LLC [Member] | National Storage Affiliates Trust [Member] | Common Shares [Member]        
Subsidiary of Limited Liability Company or Limited Partnership [Line Items]        
Shares owned by NSA Holdings (in shares)     1,000  
National Storage Affiliates Holdings LLC [Member] | NSA OP, LP [Member] | OP units [Member]        
Subsidiary of Limited Liability Company or Limited Partnership [Line Items]        
Shares owned by NSA Holdings (in shares)     126,400  
Parent Company [Member] | OP units [Member] | NSA OP, LP [Member]        
Subsidiary of Limited Liability Company or Limited Partnership [Line Items]        
Amount of OP units issued in exchange for common shares from initial public offering (in shares)   23,000,000    
Common Shares [Member]        
Subsidiary of Limited Liability Company or Limited Partnership [Line Items]        
Shares offered during initial public offering     23,000,000  
Common Shares [Member] | IPO [Member]        
Subsidiary of Limited Liability Company or Limited Partnership [Line Items]        
Shares offered during initial public offering   20,000,000    
Share price | $ / shares   $ 13.00    
Common Shares [Member] | Over-Allotment Option [Member]        
Subsidiary of Limited Liability Company or Limited Partnership [Line Items]        
Shares offered during initial public offering 3,000,000      
Net proceeds from issuance of common shares in IPO | $ $ 278,100      
Common Shares [Member]        
Subsidiary of Limited Liability Company or Limited Partnership [Line Items]        
Common share par value (in dollars per share) | $ / shares     $ 0.01