S000001247 [Member] Average Annual Total Returns |
12 Months Ended | 60 Months Ended | 120 Months Ended |
|---|---|---|---|
Dec. 31, 2025 |
Dec. 31, 2025 |
Dec. 31, 2025 |
|
| S&P 500® Index (reflects no deduction for fees, expenses, or taxes) | |||
| Prospectus [Line Items] | |||
| Average Annual Return, Percent | 17.88% | 14.42% | 14.82% |
| STOCK INDEX FUND | |||
| Prospectus [Line Items] | |||
| Average Annual Return, Percent | 17.79% | 14.33% | 14.71% |
| STOCK INDEX FUND | After Taxes on Distributions | |||
| Prospectus [Line Items] | |||
| Average Annual Return, Percent | 16.94% | 13.29% | 13.68% |
| STOCK INDEX FUND | After Taxes on Distributions and Sales | |||
| Prospectus [Line Items] | |||
| Average Annual Return, Percent | 11.07% | 11.25% | 12.02% |