v3.25.1
Label Element Value
Risk Return Abstract rr_RiskReturnAbstract  
Document Type dei_DocumentType 485BPOS
Period End Date dei_DocumentPeriodEndDate Nov. 30, 2024
Registrant Name dei_EntityRegistrantName PIONEER SERIES TRUST VIII
CIK dei_EntityCentralIndexKey 0000893660
Amendment Flag dei_AmendmentFlag false
Document Creation Date dei_DocumentCreationDate Mar. 25, 2025
Document Effective Date dei_DocumentEffectiveDate Mar. 28, 2025
Prospectus Date rr_ProspectusDate Mar. 28, 2025
Entity Inv Company Type dei_EntityInvCompanyType N-1A
Pioneer International Equity Fund | A  
Risk Return Abstract rr_RiskReturnAbstract  
Trading Symbol dei_TradingSymbol PIIFX
Pioneer International Equity Fund | C  
Risk Return Abstract rr_RiskReturnAbstract  
Trading Symbol dei_TradingSymbol PCITX
Pioneer International Equity Fund | K  
Risk Return Abstract rr_RiskReturnAbstract  
Trading Symbol dei_TradingSymbol PIEKX
Pioneer International Equity Fund | Y  
Risk Return Abstract rr_RiskReturnAbstract  
Trading Symbol dei_TradingSymbol INVYX