Vanguard Energy Index Fund Average Annual Total Returns - ETF Prospectus [Member] |
12 Months Ended | 60 Months Ended | 120 Months Ended |
|---|---|---|---|
Dec. 31, 2024 |
Dec. 31, 2024 |
Dec. 31, 2024 |
|
| MSCI US IMI/Energy 25/50 (reflects no deduction for fees, expenses, or taxes)[Member] | |||
| Prospectus [Line Items] | |||
| Average Annual Return, Percent | 6.67% | 12.76% | 4.51% |
| MSCI US Investable Market 2500 Index (reflects no deduction for fees, expenses, or taxes)[Member] | |||
| Prospectus [Line Items] | |||
| Average Annual Return, Percent | 23.82% | 14.02% | 12.64% |
| ETF Shares | After Taxes on Distributions | |||
| Prospectus [Line Items] | |||
| Average Annual Return, Percent | 5.79% | 11.57% | 3.52% |
| ETF Shares | After Taxes on Distributions and Sales | |||
| Prospectus [Line Items] | |||
| Average Annual Return, Percent | 4.48% | 9.84% | 3.22% |
| ETF Shares | Based on NAV[Member] | |||
| Prospectus [Line Items] | |||
| Average Annual Return, Percent | 6.59% | 12.65% | 4.38% |
| ETF Shares | Based on Market Price[Member] | |||
| Prospectus [Line Items] | |||
| Average Annual Return, Percent | 6.72% | 12.68% | 4.39% |