Investor A Institutional [Member] Expense Example - Investor A, Institutional - iShares Russell 2000 Small-Cap Index Fund |
Dec. 31, 2025
USD ($)
|
|---|---|
| Investor A | |
| Prospectus [Line Items] | |
| Expense Example, with Redemption, 1 Year | $ 38 |
| Expense Example, with Redemption, 3 Years | 128 |
| Expense Example, with Redemption, 5 Years | 226 |
| Expense Example, with Redemption, 10 Years | 514 |
| Institutional | |
| Prospectus [Line Items] | |
| Expense Example, with Redemption, 1 Year | 12 |
| Expense Example, with Redemption, 3 Years | 41 |
| Expense Example, with Redemption, 5 Years | 72 |
| Expense Example, with Redemption, 10 Years | $ 165 |