000001 - Document - Document and Entity Information link:presentationLink link:definitionLink link:calculationLink 020000 - Document - Risk/Return Summary {Unlabeled} - FIRST INVESTORS LIFE SERIES GOVERNMENT FUND () link:presentationLink link:definitionLink link:calculationLink 020002 - Document - Risk/Return Summary {Unlabeled} - FIRST INVESTORS LIFE SERIES INVESTMENT GRADE FUND () link:presentationLink link:definitionLink link:calculationLink 020001 - Disclosure - Risk/Return Detail Data {Elements} - FIRST INVESTORS LIFE SERIES GOVERNMENT FUND () link:presentationLink link:definitionLink link:calculationLink 020003 - Disclosure - Risk/Return Detail Data {Elements} - FIRST INVESTORS LIFE SERIES INVESTMENT GRADE FUND () link:presentationLink link:definitionLink link:calculationLink