S000001261 [Member] Average Annual Total Returns |
12 Months Ended | 60 Months Ended | 120 Months Ended |
|---|---|---|---|
Dec. 31, 2025 |
Dec. 31, 2025 |
Dec. 31, 2025 |
|
| Bloomberg U.S. Aggregate Bond Index (reflects no deduction for fees, expenses, or taxes) | |||
| Prospectus [Line Items] | |||
| Average Annual Return, Percent | 7.30% | (0.36%) | 2.01% |
| Bloomberg Intermediate U.S. Government Bond Index (reflects no deduction for fees, expenses, or taxes) | |||
| Prospectus [Line Items] | |||
| Average Annual Return, Percent | 6.50% | 0.64% | 1.76% |
| U.S. GOVERNMENT FUND | |||
| Prospectus [Line Items] | |||
| Average Annual Return, Percent | 6.07% | 0.11% | 1.29% |
| U.S. GOVERNMENT FUND | After Taxes on Distributions | |||
| Prospectus [Line Items] | |||
| Average Annual Return, Percent | 4.57% | (0.84%) | 0.41% |
| U.S. GOVERNMENT FUND | After Taxes on Distributions and Sales | |||
| Prospectus [Line Items] | |||
| Average Annual Return, Percent | 3.57% | (0.33%) | 0.60% |