Vanguard Large-Cap Index Fund Average Annual Total Returns - Institutional Prospectus [Member] |
12 Months Ended | 60 Months Ended | 120 Months Ended |
|---|---|---|---|
Dec. 31, 2025 |
Dec. 31, 2025 |
Dec. 31, 2025 |
|
| CRSP US Large Cap Index (reflects no deduction for fees, expenses, or taxes)[Member] | |||
| Prospectus [Line Items] | |||
| Average Annual Return, Percent | 18.14% | 13.95% | 14.83% |
| Dow Jones U.S. Total Stock Market Float Adjusted Index (reflects no deduction for fees, expenses, or taxes)[Member] | |||
| Prospectus [Line Items] | |||
| Average Annual Return, Percent | 17.05% | 13.07% | 14.21% |
| Institutional Shares | |||
| Prospectus [Line Items] | |||
| Average Annual Return, Percent | 18.10% | 13.92% | 14.79% |
| Institutional Shares | After Taxes on Distributions | |||
| Prospectus [Line Items] | |||
| Average Annual Return, Percent | 17.77% | 13.54% | 14.34% |
| Institutional Shares | After Taxes on Distributions and Sales | |||
| Prospectus [Line Items] | |||
| Average Annual Return, Percent | 10.91% | 11.09% | 12.35% |