Average Annual Total Returns - Tandem Fund |
12 Months Ended | 60 Months Ended | 82 Months Ended | |
|---|---|---|---|---|
Nov. 01, 2026 |
Dec. 31, 2025 |
Dec. 31, 2025 |
Dec. 31, 2025 |
|
| S&P 500® Index (does not reflect deductions for fees, expenses or taxes) | ||||
| Prospectus [Line Items] | ||||
| Average Annual Return, Percent | 17.88% | 14.42% | 15.73% | |
| Performance Inception Date | Mar. 15, 2019 | |||
| Tandem Fund Shares | ||||
| Prospectus [Line Items] | ||||
| Average Annual Return, Percent | 3.65% | 5.93% | 8.09% | |
| Performance Inception Date | Mar. 15, 2019 | |||
| Tandem Fund Shares | After Taxes on Distributions | ||||
| Prospectus [Line Items] | ||||
| Average Annual Return, Percent | 2.12% | 4.91% | 7.28% | |
| Performance Inception Date | Mar. 15, 2019 | |||
| Tandem Fund Shares | After Taxes on Distributions and Sales | ||||
| Prospectus [Line Items] | ||||
| Average Annual Return, Percent | 3.08% | 4.47% | 6.31% | |
| Performance Inception Date | Mar. 15, 2019 |