v3.26.1
S000004354 [Member] Average Annual Total Returns
 12 Months Ended 60 Months Ended 120 Months Ended 294 Months Ended
Dec. 31, 2025
Dec. 31, 2025
Dec. 31, 2025
Dec. 31, 2025
MSCI USA Index (Returns do not reflect deductions for fees, expenses or taxes)        
Prospectus [Line Items]        
Average Annual Return, Percent 17.75% 13.87% 14.79%  
NYSE Semiconductor Index (Spliced) (Returns do not reflect deductions for fees, expenses or taxes)        
Prospectus [Line Items]        
Average Annual Return, Percent [1] 41.22% 20.44% 27.88%  
iShares Semiconductor ETF        
Prospectus [Line Items]        
Average Annual Return, Percent 40.71% 19.94% 27.28%  
Performance Inception Date       Jul. 10, 2001
iShares Semiconductor ETF | After Taxes on Distributions        
Prospectus [Line Items]        
Average Annual Return, Percent 40.47% 19.70% 26.96%  
iShares Semiconductor ETF | After Taxes on Distributions and Sales        
Prospectus [Line Items]        
Average Annual Return, Percent 24.21% 16.23% 24.01%  
[1] The NYSE Semiconductor Index (Spliced) reflects the performance of the PHLX Semiconductor Sector Index through June 20, 2021 and the NYSE Semiconductor Index thereafter, which reflect the times when each index was the Underlying Index of the Fund.