Other Expenses Interest Expense [Member] Average Annual Total Returns |
12 Months Ended | 60 Months Ended | 120 Months Ended | ||||
|---|---|---|---|---|---|---|---|
Dec. 31, 2025 |
Dec. 31, 2025 |
Dec. 31, 2025 |
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| Bloomberg Municipal Bond Index (reflects no deduction for fees, expenses, or taxes) | |||||||
| Prospectus [Line Items] | |||||||
| Average Annual Return, Percent | 4.25% | 0.80% | 2.34% | ||||
| Bloomberg 5-Year General Obligation Municipal Bond Index (reflects no deduction for fees, expenses, or taxes) | |||||||
| Prospectus [Line Items] | |||||||
| Average Annual Return, Percent | 4.89% | 0.91% | 1.83% | ||||
| Composite Benchmark (reflects no deduction for fees, expenses, or taxes) | |||||||
| Prospectus [Line Items] | |||||||
| Average Annual Return, Percent | [1] | 10.49% | 4.80% | 5.73% | |||
| Class 1 | |||||||
| Prospectus [Line Items] | |||||||
| Average Annual Return, Percent | [2] | 8.99% | 3.21% | 3.75% | |||
| Class 1 | After Taxes on Distributions | |||||||
| Prospectus [Line Items] | |||||||
| Average Annual Return, Percent | [2] | 7.32% | 2.20% | 3.00% | |||
| Class 1 | After Taxes on Distributions and Sales | |||||||
| Prospectus [Line Items] | |||||||
| Average Annual Return, Percent | [2] | 6.28% | 2.47% | 2.98% | |||
| Class 2 | |||||||
| Prospectus [Line Items] | |||||||
| Average Annual Return, Percent | 9.18% | 3.40% | 3.91% | ||||
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