Vanguard SP 500 Value Index Fund Expense Example - Institutional Prospectus [Member] - Vanguard SP 500 Value Index Fund - Institutional Shares	Aug. 31, 2025 USD ($)
Prospectus [Line Items]
Expense Example, with Redemption, 1 Year	$ 5
Expense Example, with Redemption, 3 Years	16
Expense Example, with Redemption, 5 Years	28
Expense Example, with Redemption, 10 Years	$ 64

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