Class K [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 |
|
| Class K | BLACKROCK LIFEPATH INDEX 2055 FUND | Class K Shares | ||||||||||
| Prospectus [Line Items] | ||||||||||
| Annual Return [Percent] | 21.59% | 16.29% | 21.60% | (18.33%) | 18.87% | 15.02% | 26.89% | (7.79%) | 21.43% | 8.37% |