v3.26.1
Cover
Jul. 22, 2026
Document Information [Line Items]  
Document Type 8-K
Amendment Flag false
Document Period End Date Jul. 22, 2026
Current Fiscal Year End Date --12-31
Entity File Number 001-37351
Entity Registrant Name National Storage Affiliates Trust
Entity Central Index Key 0001618563
Entity Tax Identification Number 93-2834996
Entity Incorporation, State or Country Code MD
Entity Address, Address Line One 2811 Internet Boulevard
Entity Address, City or Town Frisco
Entity Address, State or Province TX
Entity Address, Postal Zip Code 75034
City Area Code 469
Local Phone Number 649-9486
Written Communications false
Soliciting Material false
Pre-commencement Tender Offer false
Pre-commencement Issuer Tender Offer false
Entity Emerging Growth Company false
Common Shares of Beneficial Interest, $0.01 par value per share  
Document Information [Line Items]  
Title of 12(b) Security Common Shares of Beneficial Interest, $0.01 par value per share
Trading Symbol NSA
Security Exchange Name NYSE
Series A Cumulative Redeemable Preferred Shares of Beneficial Interest, par value $0.01 per share  
Document Information [Line Items]  
Title of 12(b) Security Series A Cumulative Redeemable Preferred Shares of Beneficial Interest, par value $0.01 per share
Trading Symbol NSA Pr A
Security Exchange Name NYSE
Series B Cumulative Redeemable Preferred Shares of Beneficial Interest, par value $0.01 per share  
Document Information [Line Items]  
Title of 12(b) Security Series B Cumulative Redeemable Preferred Shares of Beneficial Interest, par value $0.01 per share
Trading Symbol NSA Pr B
Security Exchange Name NYSE