v3.26.1
Total Stock Market Index Portfolio Investment Objectives and Goals - Portfolio [Member] - Total Stock Market Index Portfolio
Dec. 31, 2025
Prospectus [Line Items]  
Risk/Return [Heading] <span style="font-family:Arial;font-size:13pt;font-weight:bold;">Fund Summary</span>
Objective [Heading] <span style="color:#000000;font-family:Arial;font-size:10pt;font-weight:bold;">Investment Objective</span>
Objective, Primary [Text Block] Vanguard Variable Insurance Funds Total Stock Market Index Portfolio (the “Fund”) seeks to track the performance of a benchmark index that measures the investment return of the overall stock market.