v3.24.4
Label Element Value
Risk Return Abstract rr_RiskReturnAbstract  
Document Type dei_DocumentType 485BPOS
Period End Date dei_DocumentPeriodEndDate Aug. 31, 2024
Registrant Name dei_EntityRegistrantName PIONEER SHORT TERM INCOME FUND
CIK dei_EntityCentralIndexKey 0001286364
Amendment Flag dei_AmendmentFlag false
Document Creation Date dei_DocumentCreationDate Dec. 20, 2024
Document Effective Date dei_DocumentEffectiveDate Dec. 31, 2024
Prospectus Date rr_ProspectusDate Dec. 31, 2024
Entity Inv Company Type dei_EntityInvCompanyType N-1A
Pioneer Short Term Income Fund | A  
Risk Return Abstract rr_RiskReturnAbstract  
Trading Symbol dei_TradingSymbol STABX
Pioneer Short Term Income Fund | C  
Risk Return Abstract rr_RiskReturnAbstract  
Trading Symbol dei_TradingSymbol PSHCX
Pioneer Short Term Income Fund | C2  
Risk Return Abstract rr_RiskReturnAbstract  
Trading Symbol dei_TradingSymbol STIIX
Pioneer Short Term Income Fund | K  
Risk Return Abstract rr_RiskReturnAbstract  
Trading Symbol dei_TradingSymbol STIKX
Pioneer Short Term Income Fund | Y  
Risk Return Abstract rr_RiskReturnAbstract  
Trading Symbol dei_TradingSymbol PSHYX