Quarterly report pursuant to Section 13 or 15(d)

Document and Entity Information

Document and Entity Information - shares
9 Months Ended
Sep. 30, 2015
Nov. 09, 2015
Entity [Abstract]    
Entity Registrant Name National Storage Affiliates Trust  
Entity Central Index Key 0001618563  
Current Fiscal Year End Date --12-31  
Entity Filer Category Non-accelerated Filer  
Document Type 10-Q  
Document Period End Date Sep. 30, 2015  
Document Fiscal Year Focus 2015  
Document Fiscal Period Focus Q3  
Amendment Flag false  
Entity Common Stock, Shares Outstanding   23,017,000