S000001260 [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 |
|
| TAX-EXEMPT FUND | TAX-EXEMPT FUND | ||||||||||
| Prospectus [Line Items] | ||||||||||
| Annual Return [Percent] | 3.93% | 1.95% | 5.88% | (11.20%) | 1.27% | 5.10% | 7.62% | 0.65% | 4.83% | 0.40% |