Investor A Institutional [Member] Annual Total Returns |
12 Months Ended | |||||||||
|---|---|---|---|---|---|---|---|---|---|---|
Dec. 31, 2025 |
Dec. 31, 2024 |
Dec. 31, 2023 |
Dec. 31, 2022 |
Dec. 31, 2021 |
Dec. 31, 2020 |
Dec. 31, 2019 |
Dec. 31, 2018 |
Dec. 31, 2017 |
Dec. 31, 2016 |
|
| Investor A, Institutional | iShares Russell 2000 Small-Cap Index Fund | Investor A | ||||||||||
| Prospectus [Line Items] | ||||||||||
| Annual Return [Percent] | 12.50% | 11.15% | 16.60% | (20.57%) | 14.38% | 19.66% | 25.20% | (11.19%) | 14.35% | 21.04% |