XML 7 R1.htm IDEA: XBRL DOCUMENT v3.8.0.1
Label Element Value
Risk/Return: rr_RiskReturnAbstract  
Document Type dei_DocumentType 497
Document Period End Date dei_DocumentPeriodEndDate Dec. 31, 2016
Registrant Name dei_EntityRegistrantName VANGUARD VARIABLE INSURANCE FUNDS
Central Index Key dei_EntityCentralIndexKey 0000857490
Amendment Flag dei_AmendmentFlag false
Document Creation Date dei_DocumentCreationDate Jan. 18, 2018
Document Effective Date dei_DocumentEffectiveDate Jan. 18, 2018
Prospectus Date rr_ProspectusDate Apr. 28, 2017