Label	Element	Value
Risk/Return:	rr_RiskReturnAbstract
Registrant Name	dei_EntityRegistrantName	VANGUARD VARIABLE INSURANCE FUNDS
Prospectus Date	rr_ProspectusDate	Apr. 29, 2016
Supplement [Text Block]	vvif_SupplementTextBlock	[SHIP LOGO VANGUARD (R)] Vanguard Variable Insurance Fund Money Market Portfolio Supplement to the Prospectus and Summary Prospectus Dated April 29, 2016 The following changes are effective on October 14, 2016, as a result of rules adopted by the Securities and Exchange Commission (SEC) in July 2014 and September 2015. Prospectus and Summary Prospectus Text Changes The paragraph under “Principal Investment Policies” is replaced with the following: The Portfolio invests primarily in high-quality, short-term money market instruments, including certificates of deposit, banker’s acceptances, commercial paper, Eurodollar and Yankee obligations, and other money market securities. To be considered high quality, a security must be determined by Vanguard to present minimal credit risk based in part on a consideration of maturity, portfolio diversification, portfolio liquidity, and credit quality. The Portfolio invests more than 25% of its assets in securities issued by companies in the financial services industry. The Portfolio maintains a dollar-weighted average maturity of 60 days or less and a dollar-weighted average life of 120 days or less. The last paragraph under “Principal Risks”is replaced with the following: You could lose money by investing in the Portfolio. Although the Portfolio seeks to preserve the value of your investment at $1.00 per share, it cannot guarantee it will do so. The Portfolio may impose a fee upon sale of your shares or may temporarily suspend your ability to sell shares if the Portfolio’s liquidity falls below required minimums because of market conditions or other factors. An investment in the Portfolio is not insured or guaranteed by the Federal Deposit Insurance Corporation or any other government agency. The Portfolio’s sponsor has no legal obligation to provide financial support to the Portfolio, and you should not expect that the sponsor will provide financial support to the Portfolio at any time. © 2016 The Vanguard Group, Inc. All rights reserved. Vanguard Marketing Corporation, Distributor. PS 104 102016
Money Market Portfolio
Risk/Return:	rr_RiskReturnAbstract
Supplement [Text Block]	vvif_SupplementTextBlock	[SHIP LOGO VANGUARD (R)] Vanguard Variable Insurance Fund Money Market Portfolio Supplement to the Prospectus and Summary Prospectus Dated April 29, 2016 The following changes are effective on October 14, 2016, as a result of rules adopted by the Securities and Exchange Commission (SEC) in July 2014 and September 2015. Prospectus and Summary Prospectus Text Changes The paragraph under “Principal Investment Policies” is replaced with the following: The Portfolio invests primarily in high-quality, short-term money market instruments, including certificates of deposit, banker’s acceptances, commercial paper, Eurodollar and Yankee obligations, and other money market securities. To be considered high quality, a security must be determined by Vanguard to present minimal credit risk based in part on a consideration of maturity, portfolio diversification, portfolio liquidity, and credit quality. The Portfolio invests more than 25% of its assets in securities issued by companies in the financial services industry. The Portfolio maintains a dollar-weighted average maturity of 60 days or less and a dollar-weighted average life of 120 days or less. The last paragraph under “Principal Risks”is replaced with the following: You could lose money by investing in the Portfolio. Although the Portfolio seeks to preserve the value of your investment at $1.00 per share, it cannot guarantee it will do so. The Portfolio may impose a fee upon sale of your shares or may temporarily suspend your ability to sell shares if the Portfolio’s liquidity falls below required minimums because of market conditions or other factors. An investment in the Portfolio is not insured or guaranteed by the Federal Deposit Insurance Corporation or any other government agency. The Portfolio’s sponsor has no legal obligation to provide financial support to the Portfolio, and you should not expect that the sponsor will provide financial support to the Portfolio at any time. © 2016 The Vanguard Group, Inc. All rights reserved. Vanguard Marketing Corporation, Distributor. PS 104 102016