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 California Municipal Opportunities Fund | Class K | ||||||||||
| Prospectus [Line Items] | ||||||||||
| Annual Return [Percent] | 3.12% | 3.45% | 5.32% | (8.17%) | 4.83% | 1.50% | 6.48% | 1.30% | 7.24% | 0.42% |