S000004360 [Member] Annual Total Returns |
12 Months Ended | |||||||||
|---|---|---|---|---|---|---|---|---|---|---|
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 |
Dec. 31, 2015 |
|
| iShares 20+ Year Treasury Bond ETF | iShares 20+ Year Treasury Bond ETF | ||||||||||
| Prospectus [Line Items] | ||||||||||
| Annual Return [Percent] | (7.84%) | 2.96% | (31.41%) | (4.76%) | 17.92% | 14.93% | (2.07%) | 8.92% | 1.36% | (1.65%) |