Vanguard Real Estate Index Fund Expense Example - Institutional Prospectus [Member] - Vanguard Real Estate Index Fund - Institutional Shares	Jan. 31, 2026 USD ($)
Prospectus [Line Items]
Expense Example, with Redemption, 1 Year	$ 11
Expense Example, with Redemption, 3 Years	35
Expense Example, with Redemption, 5 Years	62
Expense Example, with Redemption, 10 Years	$ 141

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