S000012102 [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 |
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| S000012102 [Member] | C000033005 [Member] | ||||||||||||
| Prospectus [Line Items] | ||||||||||||
| Annual Return [Percent] | [1] | 8.64% | 21.36% | (8.83%) | 28.76% | 7.83% | 20.96% | (18.32%) | 13.91% | 32.32% | (6.48%) | |
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