v3.26.1
S000004349 [Member] Average Annual Total Returns
12 Months Ended 60 Months Ended 120 Months Ended 299 Months Ended
Dec. 31, 2025
Dec. 31, 2025
Dec. 31, 2025
Dec. 31, 2025
S&P Total Market Index (Returns do not reflect deductions for fees, expenses or taxes)        
Prospectus [Line Items]        
Average Annual Return, Percent 17.05% 13.07% 14.22%  
Cohen & Steers Realty Majors Index (Returns do not reflect deductions for fees, expenses or taxes)        
Prospectus [Line Items]        
Average Annual Return, Percent 2.27% 5.10% 5.19%  
iShares Select U.S. REIT ETF        
Prospectus [Line Items]        
Average Annual Return, Percent 1.94% 4.74% 4.83%  
Performance Inception Date       Jan. 29, 2001
iShares Select U.S. REIT ETF | After Taxes on Distributions        
Prospectus [Line Items]        
Average Annual Return, Percent 0.98% 3.83% 3.73%  
iShares Select U.S. REIT ETF | After Taxes on Distributions and Sales        
Prospectus [Line Items]        
Average Annual Return, Percent 1.36% 3.39% 3.34%