v3.26.1
Vanguard SP Mid-Cap 400 Growth Index Fund Annual Fund Operating Expenses - Institutional Prospectus [Member] - Vanguard SP Mid-Cap 400 Growth Index Fund - Institutional Shares
Aug. 31, 2025
Prospectus [Line Items]  
Management Fees (as a percentage of Assets) 0.02%
Distribution and Service (12b-1) Fees 0.00%
Other Expenses (as a percentage of Assets): 0.01%
Expenses (as a percentage of Assets) 0.03% [1]
[1] The expense information shown in the table has been restated to reflect current fees.