3.22.4 html 342 89 1 true 118 0 false 2 false false R1.htm 000001 - Document - Document and Entity Information Sheet http://www.sei.com/20230127/role/DocumentAndEntityInformation Document and Entity Information 1 false true R2.htm 020000 - Document - Risk/Return Summary {Unlabeled} - Class F Prospectus - SIMT Large Cap Fund (Class F) Sheet http://www.sei.com/20230127/role/DocumentRiskReturnSummaryUnlabeledClassFProspectusSIMTLargeCapFundClassF Risk/Return Summary- Class F Prospectus - SIMT Large Cap Fund (Class F) 2 false false R7.htm 020005 - Disclosure - Risk/Return Detail Data {Elements} - Class F Prospectus - SIMT Large Cap Fund (Class F) Sheet http://www.sei.com/20230127/role/DisclosureRiskReturnDetailDataElementsClassFProspectusSIMTLargeCapFundClassF Risk/Return Detail Data- Class F Prospectus - SIMT Large Cap Fund (Class F) 3 false true R8.htm 020006 - Document - Risk/Return Summary {Unlabeled} - Class F Prospectus - SIMT LARGE CAP VALUE FUND (CLASS F) Sheet http://www.sei.com/20230127/role/DocumentRiskReturnSummaryUnlabeledClassFProspectusSIMTLARGECAPVALUEFUNDCLASSF Risk/Return Summary- Class F Prospectus - SIMT LARGE CAP VALUE FUND (CLASS F) 4 false false R13.htm 020011 - Disclosure - Risk/Return Detail Data {Elements} - Class F Prospectus - SIMT LARGE CAP VALUE FUND (CLASS F) Sheet http://www.sei.com/20230127/role/DisclosureRiskReturnDetailDataElementsClassFProspectusSIMTLARGECAPVALUEFUNDCLASSF Risk/Return Detail Data- Class F Prospectus - SIMT LARGE CAP VALUE FUND (CLASS F) 5 false true R14.htm 020012 - Document - Risk/Return Summary {Unlabeled} - Class F Prospectus - SIMT LARGE CAP GROWTH FUND (CLASS F) Sheet http://www.sei.com/20230127/role/DocumentRiskReturnSummaryUnlabeledClassFProspectusSIMTLARGECAPGROWTHFUNDCLASSF Risk/Return Summary- Class F Prospectus - SIMT LARGE CAP GROWTH FUND (CLASS F) 6 false false R19.htm 020017 - Disclosure - Risk/Return Detail Data {Elements} - Class F Prospectus - SIMT LARGE CAP GROWTH FUND (CLASS F) Sheet http://www.sei.com/20230127/role/DisclosureRiskReturnDetailDataElementsClassFProspectusSIMTLARGECAPGROWTHFUNDCLASSF Risk/Return Detail Data- Class F Prospectus - SIMT LARGE CAP GROWTH FUND (CLASS F) 7 false true R20.htm 020018 - Document - Risk/Return Summary {Unlabeled} - Class F Prospectus - SIMT Large Cap Index Fund Sheet http://www.sei.com/20230127/role/DocumentRiskReturnSummaryUnlabeledClassFProspectusSIMTLargeCapIndexFund Risk/Return Summary- Class F Prospectus - SIMT Large Cap Index Fund 8 false false R25.htm 020023 - Disclosure - Risk/Return Detail Data {Elements} - Class F Prospectus - SIMT Large Cap Index Fund Sheet http://www.sei.com/20230127/role/DisclosureRiskReturnDetailDataElementsClassFProspectusSIMTLargeCapIndexFund Risk/Return Detail Data- Class F Prospectus - SIMT Large Cap Index Fund 9 false true R26.htm 020024 - Document - Risk/Return Summary {Unlabeled} - Class F Prospectus - SIMT TAX-MANAGED LARGE CAP FUND (CLASS F) Sheet http://www.sei.com/20230127/role/DocumentRiskReturnSummaryUnlabeledClassFProspectusSIMTTAXMANAGEDLARGECAPFUNDCLASSF Risk/Return Summary- Class F Prospectus - SIMT TAX-MANAGED LARGE CAP FUND (CLASS F) 10 false false R31.htm 020029 - Disclosure - Risk/Return Detail Data {Elements} - Class F Prospectus - SIMT TAX-MANAGED LARGE CAP FUND (CLASS F) Sheet http://www.sei.com/20230127/role/DisclosureRiskReturnDetailDataElementsClassFProspectusSIMTTAXMANAGEDLARGECAPFUNDCLASSF Risk/Return Detail Data- Class F Prospectus - SIMT TAX-MANAGED LARGE CAP FUND (CLASS F) 11 false true R32.htm 020030 - Document - Risk/Return Summary {Unlabeled} - Class F Prospectus - SIMT S&P 500 Index Fund (Class F) Sheet http://www.sei.com/20230127/role/DocumentRiskReturnSummaryUnlabeledClassFProspectusSIMTSP500IndexFundClassF Risk/Return Summary- Class F Prospectus - SIMT S&P 500 Index Fund (Class F) 12 false false R37.htm 020035 - Disclosure - Risk/Return Detail Data {Elements} - Class F Prospectus - SIMT S&P 500 Index Fund (Class F) Sheet http://www.sei.com/20230127/role/DisclosureRiskReturnDetailDataElementsClassFProspectusSIMTSP500IndexFundClassF Risk/Return Detail Data- Class F Prospectus - SIMT S&P 500 Index Fund (Class F) 13 false true R38.htm 020036 - Document - Risk/Return Summary {Unlabeled} - Class F Prospectus - SIMT Small Cap Fund (Class F) Sheet http://www.sei.com/20230127/role/DocumentRiskReturnSummaryUnlabeledClassFProspectusSIMTSmallCapFundClassF Risk/Return Summary- Class F Prospectus - SIMT Small Cap Fund (Class F) 14 false false R43.htm 020041 - Disclosure - Risk/Return Detail Data {Elements} - Class F Prospectus - SIMT Small Cap Fund (Class F) Sheet http://www.sei.com/20230127/role/DisclosureRiskReturnDetailDataElementsClassFProspectusSIMTSmallCapFundClassF Risk/Return Detail Data- Class F Prospectus - SIMT Small Cap Fund (Class F) 15 false true R44.htm 020042 - Document - Risk/Return Summary {Unlabeled} - Class F Prospectus - SIMT SMALL CAP VALUE FUND (CLASS F) Sheet http://www.sei.com/20230127/role/DocumentRiskReturnSummaryUnlabeledClassFProspectusSIMTSMALLCAPVALUEFUNDCLASSF Risk/Return Summary- Class F Prospectus - SIMT SMALL CAP VALUE FUND (CLASS F) 16 false false R49.htm 020047 - Disclosure - Risk/Return Detail Data {Elements} - Class F Prospectus - SIMT SMALL CAP VALUE FUND (CLASS F) Sheet http://www.sei.com/20230127/role/DisclosureRiskReturnDetailDataElementsClassFProspectusSIMTSMALLCAPVALUEFUNDCLASSF Risk/Return Detail Data- Class F Prospectus - SIMT SMALL CAP VALUE FUND (CLASS F) 17 false true R50.htm 020048 - Document - Risk/Return Summary {Unlabeled} - Class F Prospectus - SIMT SMALL CAP GROWTH FUND (CLASS F) Sheet http://www.sei.com/20230127/role/DocumentRiskReturnSummaryUnlabeledClassFProspectusSIMTSMALLCAPGROWTHFUNDCLASSF Risk/Return Summary- Class F Prospectus - SIMT SMALL CAP GROWTH FUND (CLASS F) 18 false false R55.htm 020053 - Disclosure - Risk/Return Detail Data {Elements} - Class F Prospectus - SIMT SMALL CAP GROWTH FUND (CLASS F) Sheet http://www.sei.com/20230127/role/DisclosureRiskReturnDetailDataElementsClassFProspectusSIMTSMALLCAPGROWTHFUNDCLASSF Risk/Return Detail Data- Class F Prospectus - SIMT SMALL CAP GROWTH FUND (CLASS F) 19 false true R56.htm 020054 - Document - Risk/Return Summary {Unlabeled} - Class F Prospectus - SIMT TAX-MANAGED SMALL/MID CAP FUND (CLASS F) Sheet http://www.sei.com/20230127/role/DocumentRiskReturnSummaryUnlabeledClassFProspectusSIMTTAXMANAGEDSMALLMIDCAPFUNDCLASSF Risk/Return Summary- Class F Prospectus - SIMT TAX-MANAGED SMALL/MID CAP FUND (CLASS F) 20 false false R61.htm 020059 - Disclosure - Risk/Return Detail Data {Elements} - Class F Prospectus - SIMT TAX-MANAGED SMALL/MID CAP FUND (CLASS F) Sheet http://www.sei.com/20230127/role/DisclosureRiskReturnDetailDataElementsClassFProspectusSIMTTAXMANAGEDSMALLMIDCAPFUNDCLASSF Risk/Return Detail Data- Class F Prospectus - SIMT TAX-MANAGED SMALL/MID CAP FUND (CLASS F) 21 false true R62.htm 020060 - Document - Risk/Return Summary {Unlabeled} - Class F Prospectus - SIMT MID CAP FUND (CLASS F) Sheet http://www.sei.com/20230127/role/DocumentRiskReturnSummaryUnlabeledClassFProspectusSIMTMIDCAPFUNDCLASSF Risk/Return Summary- Class F Prospectus - SIMT MID CAP FUND (CLASS F) 22 false false R67.htm 020065 - Disclosure - Risk/Return Detail Data {Elements} - Class F Prospectus - SIMT MID CAP FUND (CLASS F) Sheet http://www.sei.com/20230127/role/DisclosureRiskReturnDetailDataElementsClassFProspectusSIMTMIDCAPFUNDCLASSF Risk/Return Detail Data- Class F Prospectus - SIMT MID CAP FUND (CLASS F) 23 false true R68.htm 020066 - Document - Risk/Return Summary {Unlabeled} - Class F Prospectus - SIMT US MANAGED VOLATILITY FUND (CLASS F) Sheet http://www.sei.com/20230127/role/DocumentRiskReturnSummaryUnlabeledClassFProspectusSIMTUSMANAGEDVOLATILITYFUNDCLASSF Risk/Return Summary- Class F Prospectus - SIMT US MANAGED VOLATILITY FUND (CLASS F) 24 false false R73.htm 020071 - Disclosure - Risk/Return Detail Data {Elements} - Class F Prospectus - SIMT US MANAGED VOLATILITY FUND (CLASS F) Sheet http://www.sei.com/20230127/role/DisclosureRiskReturnDetailDataElementsClassFProspectusSIMTUSMANAGEDVOLATILITYFUNDCLASSF Risk/Return Detail Data- Class F Prospectus - SIMT US MANAGED VOLATILITY FUND (CLASS F) 25 false true R74.htm 020072 - Document - Risk/Return Summary {Unlabeled} - Class F Prospectus - SIMT GLOBAL MANAGED VOLATILITY FUND (CLASS F) Sheet http://www.sei.com/20230127/role/DocumentRiskReturnSummaryUnlabeledClassFProspectusSIMTGLOBALMANAGEDVOLATILITYFUNDCLASSF Risk/Return Summary- Class F Prospectus - SIMT GLOBAL MANAGED VOLATILITY FUND (CLASS F) 26 false false R79.htm 020077 - Disclosure - Risk/Return Detail Data {Elements} - Class F Prospectus - SIMT GLOBAL MANAGED VOLATILITY FUND (CLASS F) Sheet http://www.sei.com/20230127/role/DisclosureRiskReturnDetailDataElementsClassFProspectusSIMTGLOBALMANAGEDVOLATILITYFUNDCLASSF Risk/Return Detail Data- Class F Prospectus - SIMT GLOBAL MANAGED VOLATILITY FUND (CLASS F) 27 false true R80.htm 020078 - Document - Risk/Return Summary {Unlabeled} - Class F Prospectus - SIMT Tax-Managed Managed Volatility Fund (Class F) Sheet http://www.sei.com/20230127/role/DocumentRiskReturnSummaryUnlabeledClassFProspectusSIMTTaxManagedManagedVolatilityFundClassF Risk/Return Summary- Class F Prospectus - SIMT Tax-Managed Managed Volatility Fund (Class F) 28 false false R85.htm 020083 - Disclosure - Risk/Return Detail Data {Elements} - Class F Prospectus - SIMT Tax-Managed Managed Volatility Fund (Class F) Sheet http://www.sei.com/20230127/role/DisclosureRiskReturnDetailDataElementsClassFProspectusSIMTTaxManagedManagedVolatilityFundClassF Risk/Return Detail Data- Class F Prospectus - SIMT Tax-Managed Managed Volatility Fund (Class F) 29 false true R86.htm 020084 - Document - Risk/Return Summary {Unlabeled} - Class F Prospectus - SIMT Tax-Managed International Managed Volatility Fund (Class F) Sheet http://www.sei.com/20230127/role/DocumentRiskReturnSummaryUnlabeledClassFProspectusSIMTTaxManagedInternationalManagedVolatilityFundClassF Risk/Return Summary- Class F Prospectus - SIMT Tax-Managed International Managed Volatility Fund (Class F) 30 false false R91.htm 020089 - Disclosure - Risk/Return Detail Data {Elements} - Class F Prospectus - SIMT Tax-Managed International Managed Volatility Fund (Class F) Sheet http://www.sei.com/20230127/role/DisclosureRiskReturnDetailDataElementsClassFProspectusSIMTTaxManagedInternationalManagedVolatilityFundClassF Risk/Return Detail Data- Class F Prospectus - SIMT Tax-Managed International Managed Volatility Fund (Class F) 31 false true R92.htm 020090 - Document - Risk/Return Summary {Unlabeled} - Class F Prospectus - SIMT REAL ESTATE FUND (CLASS F) Sheet http://www.sei.com/20230127/role/DocumentRiskReturnSummaryUnlabeledClassFProspectusSIMTREALESTATEFUNDCLASSF Risk/Return Summary- Class F Prospectus - SIMT REAL ESTATE FUND (CLASS F) 32 false false R97.htm 020095 - Disclosure - Risk/Return Detail Data {Elements} - Class F Prospectus - SIMT REAL ESTATE FUND (CLASS F) Sheet http://www.sei.com/20230127/role/DisclosureRiskReturnDetailDataElementsClassFProspectusSIMTREALESTATEFUNDCLASSF Risk/Return Detail Data- Class F Prospectus - SIMT REAL ESTATE FUND (CLASS F) 33 false true R98.htm 020096 - Document - Risk/Return Summary {Unlabeled} - Class F Prospectus - SIMT CORE FIXED INCOME FUND (CLASS F) Sheet http://www.sei.com/20230127/role/DocumentRiskReturnSummaryUnlabeledClassFProspectusSIMTCOREFIXEDINCOMEFUNDCLASSF Risk/Return Summary- Class F Prospectus - SIMT CORE FIXED INCOME FUND (CLASS F) 34 false false R103.htm 020101 - Disclosure - Risk/Return Detail Data {Elements} - Class F Prospectus - SIMT CORE FIXED INCOME FUND (CLASS F) Sheet http://www.sei.com/20230127/role/DisclosureRiskReturnDetailDataElementsClassFProspectusSIMTCOREFIXEDINCOMEFUNDCLASSF Risk/Return Detail Data- Class F Prospectus - SIMT CORE FIXED INCOME FUND (CLASS F) 35 false true R104.htm 020102 - Document - Risk/Return Summary {Unlabeled} - Class F Prospectus - SIMT HIGH YIELD BOND FUND (CLASS F) Sheet http://www.sei.com/20230127/role/DocumentRiskReturnSummaryUnlabeledClassFProspectusSIMTHIGHYIELDBONDFUNDCLASSF Risk/Return Summary- Class F Prospectus - SIMT HIGH YIELD BOND FUND (CLASS F) 36 false false R109.htm 020107 - Disclosure - Risk/Return Detail Data {Elements} - Class F Prospectus - SIMT HIGH YIELD BOND FUND (CLASS F) Sheet http://www.sei.com/20230127/role/DisclosureRiskReturnDetailDataElementsClassFProspectusSIMTHIGHYIELDBONDFUNDCLASSF Risk/Return Detail Data- Class F Prospectus - SIMT HIGH YIELD BOND FUND (CLASS F) 37 false true R110.htm 020108 - Document - Risk/Return Summary {Unlabeled} - Class F Prospectus - SIMT Conservative Income Fund (Class F) Sheet http://www.sei.com/20230127/role/DocumentRiskReturnSummaryUnlabeledClassFProspectusSIMTConservativeIncomeFundClassF Risk/Return Summary- Class F Prospectus - SIMT Conservative Income Fund (Class F) 38 false false R115.htm 020113 - Disclosure - Risk/Return Detail Data {Elements} - Class F Prospectus - SIMT Conservative Income Fund (Class F) Sheet http://www.sei.com/20230127/role/DisclosureRiskReturnDetailDataElementsClassFProspectusSIMTConservativeIncomeFundClassF Risk/Return Detail Data- Class F Prospectus - SIMT Conservative Income Fund (Class F) 39 false true R116.htm 020114 - Document - Risk/Return Summary {Unlabeled} - Class F Prospectus - SIMT Tax-Free Conservative Income Fund (Class F) Sheet http://www.sei.com/20230127/role/DocumentRiskReturnSummaryUnlabeledClassFProspectusSIMTTaxFreeConservativeIncomeFundClassF Risk/Return Summary- Class F Prospectus - SIMT Tax-Free Conservative Income Fund (Class F) 40 false false R121.htm 020119 - Disclosure - Risk/Return Detail Data {Elements} - Class F Prospectus - SIMT Tax-Free Conservative Income Fund (Class F) Sheet http://www.sei.com/20230127/role/DisclosureRiskReturnDetailDataElementsClassFProspectusSIMTTaxFreeConservativeIncomeFundClassF Risk/Return Detail Data- Class F Prospectus - SIMT Tax-Free Conservative Income Fund (Class F) 41 false true R122.htm 020120 - Document - Risk/Return Summary {Unlabeled} - Class F Prospectus - SIMT Real Return Fund (Class F) Sheet http://www.sei.com/20230127/role/DocumentRiskReturnSummaryUnlabeledClassFProspectusSIMTRealReturnFundClassF Risk/Return Summary- Class F Prospectus - SIMT Real Return Fund (Class F) 42 false false R127.htm 020125 - Disclosure - Risk/Return Detail Data {Elements} - Class F Prospectus - SIMT Real Return Fund (Class F) Sheet http://www.sei.com/20230127/role/DisclosureRiskReturnDetailDataElementsClassFProspectusSIMTRealReturnFundClassF Risk/Return Detail Data- Class F Prospectus - SIMT Real Return Fund (Class F) 43 false true R128.htm 020126 - Document - Risk/Return Summary {Unlabeled} - Class F Prospectus - SIMT Dynamic Asset Allocation Fund (Class F) Sheet http://www.sei.com/20230127/role/DocumentRiskReturnSummaryUnlabeledClassFProspectusSIMTDynamicAssetAllocationFundClassF Risk/Return Summary- Class F Prospectus - SIMT Dynamic Asset Allocation Fund (Class F) 44 false false R133.htm 020131 - Disclosure - Risk/Return Detail Data {Elements} - Class F Prospectus - SIMT Dynamic Asset Allocation Fund (Class F) Sheet http://www.sei.com/20230127/role/DisclosureRiskReturnDetailDataElementsClassFProspectusSIMTDynamicAssetAllocationFundClassF Risk/Return Detail Data- Class F Prospectus - SIMT Dynamic Asset Allocation Fund (Class F) 45 false true R134.htm 020132 - Document - Risk/Return Summary {Unlabeled} - Class F Prospectus - SIMT Multi-Strategy Alternative Fund (Class F) Sheet http://www.sei.com/20230127/role/DocumentRiskReturnSummaryUnlabeledClassFProspectusSIMTMultiStrategyAlternativeFundClassF Risk/Return Summary- Class F Prospectus - SIMT Multi-Strategy Alternative Fund (Class F) 46 false false R139.htm 020137 - Disclosure - Risk/Return Detail Data {Elements} - Class F Prospectus - SIMT Multi-Strategy Alternative Fund (Class F) Sheet http://www.sei.com/20230127/role/DisclosureRiskReturnDetailDataElementsClassFProspectusSIMTMultiStrategyAlternativeFundClassF Risk/Return Detail Data- Class F Prospectus - SIMT Multi-Strategy Alternative Fund (Class F) 47 false true R140.htm 020138 - Document - Risk/Return Summary {Unlabeled} - Class I Prospectus - SIMT Large Cap Fund (- Class I, Class F) Sheet http://www.sei.com/20230127/role/DocumentRiskReturnSummaryUnlabeledClassIProspectusSIMTLargeCapFundClassIClassF Risk/Return Summary- Class I Prospectus - SIMT Large Cap Fund (- Class I, Class F) 48 false false R145.htm 020143 - Disclosure - Risk/Return Detail Data {Elements} - Class I Prospectus - SIMT Large Cap Fund (- Class I, Class F) Sheet http://www.sei.com/20230127/role/DisclosureRiskReturnDetailDataElementsClassIProspectusSIMTLargeCapFundClassIClassF Risk/Return Detail Data- Class I Prospectus - SIMT Large Cap Fund (- Class I, Class F) 49 false true R146.htm 020144 - Document - Risk/Return Summary {Unlabeled} - Class I Prospectus - SIMT LARGE CAP VALUE FUND (CLASS I) Sheet http://www.sei.com/20230127/role/DocumentRiskReturnSummaryUnlabeledClassIProspectusSIMTLARGECAPVALUEFUNDCLASSI Risk/Return Summary- Class I Prospectus - SIMT LARGE CAP VALUE FUND (CLASS I) 50 false false R151.htm 020149 - Disclosure - Risk/Return Detail Data {Elements} - Class I Prospectus - SIMT LARGE CAP VALUE FUND (CLASS I) Sheet http://www.sei.com/20230127/role/DisclosureRiskReturnDetailDataElementsClassIProspectusSIMTLARGECAPVALUEFUNDCLASSI Risk/Return Detail Data- Class I Prospectus - SIMT LARGE CAP VALUE FUND (CLASS I) 51 false true R152.htm 020150 - Document - Risk/Return Summary {Unlabeled} - Class I Prospectus - SIMT LARGE CAP GROWTH FUND (CLASS I) Sheet http://www.sei.com/20230127/role/DocumentRiskReturnSummaryUnlabeledClassIProspectusSIMTLARGECAPGROWTHFUNDCLASSI Risk/Return Summary- Class I Prospectus - SIMT LARGE CAP GROWTH FUND (CLASS I) 52 false false R157.htm 020155 - Disclosure - Risk/Return Detail Data {Elements} - Class I Prospectus - SIMT LARGE CAP GROWTH FUND (CLASS I) Sheet http://www.sei.com/20230127/role/DisclosureRiskReturnDetailDataElementsClassIProspectusSIMTLARGECAPGROWTHFUNDCLASSI Risk/Return Detail Data- Class I Prospectus - SIMT LARGE CAP GROWTH FUND (CLASS I) 53 false true R158.htm 020156 - Document - Risk/Return Summary {Unlabeled} - Class I Prospectus - SIMT S&P 500 Index Fund (Class I) Sheet http://www.sei.com/20230127/role/DocumentRiskReturnSummaryUnlabeledClassIProspectusSIMTSP500IndexFundClassI Risk/Return Summary- Class I Prospectus - SIMT S&P 500 Index Fund (Class I) 54 false false R163.htm 020161 - Disclosure - Risk/Return Detail Data {Elements} - Class I Prospectus - SIMT S&P 500 Index Fund (Class I) Sheet http://www.sei.com/20230127/role/DisclosureRiskReturnDetailDataElementsClassIProspectusSIMTSP500IndexFundClassI Risk/Return Detail Data- Class I Prospectus - SIMT S&P 500 Index Fund (Class I) 55 false true R164.htm 020162 - Document - Risk/Return Summary {Unlabeled} - Class I Prospectus - SIMT Small Cap Fund (- Class I, Class F) Sheet http://www.sei.com/20230127/role/DocumentRiskReturnSummaryUnlabeledClassIProspectusSIMTSmallCapFundClassIClassF Risk/Return Summary- Class I Prospectus - SIMT Small Cap Fund (- Class I, Class F) 56 false false R169.htm 020167 - Disclosure - Risk/Return Detail Data {Elements} - Class I Prospectus - SIMT Small Cap Fund (- Class I, Class F) Sheet http://www.sei.com/20230127/role/DisclosureRiskReturnDetailDataElementsClassIProspectusSIMTSmallCapFundClassIClassF Risk/Return Detail Data- Class I Prospectus - SIMT Small Cap Fund (- Class I, Class F) 57 false true R170.htm 020168 - Document - Risk/Return Summary {Unlabeled} - Class I Prospectus - SIMT SMALL CAP VALUE FUND (CLASS I) Sheet http://www.sei.com/20230127/role/DocumentRiskReturnSummaryUnlabeledClassIProspectusSIMTSMALLCAPVALUEFUNDCLASSI Risk/Return Summary- Class I Prospectus - SIMT SMALL CAP VALUE FUND (CLASS I) 58 false false R175.htm 020173 - Disclosure - Risk/Return Detail Data {Elements} - Class I Prospectus - SIMT SMALL CAP VALUE FUND (CLASS I) Sheet http://www.sei.com/20230127/role/DisclosureRiskReturnDetailDataElementsClassIProspectusSIMTSMALLCAPVALUEFUNDCLASSI Risk/Return Detail Data- Class I Prospectus - SIMT SMALL CAP VALUE FUND (CLASS I) 59 false true R176.htm 020174 - Document - Risk/Return Summary {Unlabeled} - Class I Prospectus - SIMT SMALL CAP GROWTH FUND (CLASS I) Sheet http://www.sei.com/20230127/role/DocumentRiskReturnSummaryUnlabeledClassIProspectusSIMTSMALLCAPGROWTHFUNDCLASSI Risk/Return Summary- Class I Prospectus - SIMT SMALL CAP GROWTH FUND (CLASS I) 60 false false R181.htm 020179 - Disclosure - Risk/Return Detail Data {Elements} - Class I Prospectus - SIMT SMALL CAP GROWTH FUND (CLASS I) Sheet http://www.sei.com/20230127/role/DisclosureRiskReturnDetailDataElementsClassIProspectusSIMTSMALLCAPGROWTHFUNDCLASSI Risk/Return Detail Data- Class I Prospectus - SIMT SMALL CAP GROWTH FUND (CLASS I) 61 false true R182.htm 020180 - Document - Risk/Return Summary {Unlabeled} - Class I Prospectus - SIMT MID CAP FUND (CLASS I) Sheet http://www.sei.com/20230127/role/DocumentRiskReturnSummaryUnlabeledClassIProspectusSIMTMIDCAPFUNDCLASSI Risk/Return Summary- Class I Prospectus - SIMT MID CAP FUND (CLASS I) 62 false false R187.htm 020185 - Disclosure - Risk/Return Detail Data {Elements} - Class I Prospectus - SIMT MID CAP FUND (CLASS I) Sheet http://www.sei.com/20230127/role/DisclosureRiskReturnDetailDataElementsClassIProspectusSIMTMIDCAPFUNDCLASSI Risk/Return Detail Data- Class I Prospectus - SIMT MID CAP FUND (CLASS I) 63 false true R188.htm 020186 - Document - Risk/Return Summary {Unlabeled} - Class I Prospectus - SIMT US MANAGED VOLATILITY FUND (Class I) Sheet http://www.sei.com/20230127/role/DocumentRiskReturnSummaryUnlabeledClassIProspectusSIMTUSMANAGEDVOLATILITYFUNDClassI Risk/Return Summary- Class I Prospectus - SIMT US MANAGED VOLATILITY FUND (Class I) 64 false false R193.htm 020191 - Disclosure - Risk/Return Detail Data {Elements} - Class I Prospectus - SIMT US MANAGED VOLATILITY FUND (Class I) Sheet http://www.sei.com/20230127/role/DisclosureRiskReturnDetailDataElementsClassIProspectusSIMTUSMANAGEDVOLATILITYFUNDClassI Risk/Return Detail Data- Class I Prospectus - SIMT US MANAGED VOLATILITY FUND (Class I) 65 false true R194.htm 020192 - Document - Risk/Return Summary {Unlabeled} - Class I Prospectus - SIMT GLOBAL MANAGED VOLATILITY FUND (Class I) Sheet http://www.sei.com/20230127/role/DocumentRiskReturnSummaryUnlabeledClassIProspectusSIMTGLOBALMANAGEDVOLATILITYFUNDClassI Risk/Return Summary- Class I Prospectus - SIMT GLOBAL MANAGED VOLATILITY FUND (Class I) 66 false false R199.htm 020197 - Disclosure - Risk/Return Detail Data {Elements} - Class I Prospectus - SIMT GLOBAL MANAGED VOLATILITY FUND (Class I) Sheet http://www.sei.com/20230127/role/DisclosureRiskReturnDetailDataElementsClassIProspectusSIMTGLOBALMANAGEDVOLATILITYFUNDClassI Risk/Return Detail Data- Class I Prospectus - SIMT GLOBAL MANAGED VOLATILITY FUND (Class I) 67 false true R200.htm 020198 - Document - Risk/Return Summary {Unlabeled} - Class I Prospectus - SIMT REAL ESTATE FUND (Class I) Sheet http://www.sei.com/20230127/role/DocumentRiskReturnSummaryUnlabeledClassIProspectusSIMTREALESTATEFUNDClassI Risk/Return Summary- Class I Prospectus - SIMT REAL ESTATE FUND (Class I) 68 false false R205.htm 020203 - Disclosure - Risk/Return Detail Data {Elements} - Class I Prospectus - SIMT REAL ESTATE FUND (Class I) Sheet http://www.sei.com/20230127/role/DisclosureRiskReturnDetailDataElementsClassIProspectusSIMTREALESTATEFUNDClassI Risk/Return Detail Data- Class I Prospectus - SIMT REAL ESTATE FUND (Class I) 69 false true R206.htm 020204 - Document - Risk/Return Summary {Unlabeled} - Class I Prospectus - SIMT CORE FIXED INCOME FUND (CLASS I) Sheet http://www.sei.com/20230127/role/DocumentRiskReturnSummaryUnlabeledClassIProspectusSIMTCOREFIXEDINCOMEFUNDCLASSI Risk/Return Summary- Class I Prospectus - SIMT CORE FIXED INCOME FUND (CLASS I) 70 false false R211.htm 020209 - Disclosure - Risk/Return Detail Data {Elements} - Class I Prospectus - SIMT CORE FIXED INCOME FUND (CLASS I) Sheet http://www.sei.com/20230127/role/DisclosureRiskReturnDetailDataElementsClassIProspectusSIMTCOREFIXEDINCOMEFUNDCLASSI Risk/Return Detail Data- Class I Prospectus - SIMT CORE FIXED INCOME FUND (CLASS I) 71 false true R212.htm 020210 - Document - Risk/Return Summary {Unlabeled} - Class I Prospectus - SIMT HIGH YIELD BOND FUND (Class I) Sheet http://www.sei.com/20230127/role/DocumentRiskReturnSummaryUnlabeledClassIProspectusSIMTHIGHYIELDBONDFUNDClassI Risk/Return Summary- Class I Prospectus - SIMT HIGH YIELD BOND FUND (Class I) 72 false false R217.htm 020215 - Disclosure - Risk/Return Detail Data {Elements} - Class I Prospectus - SIMT HIGH YIELD BOND FUND (Class I) Sheet http://www.sei.com/20230127/role/DisclosureRiskReturnDetailDataElementsClassIProspectusSIMTHIGHYIELDBONDFUNDClassI Risk/Return Detail Data- Class I Prospectus - SIMT HIGH YIELD BOND FUND (Class I) 73 false true R218.htm 020216 - Document - Risk/Return Summary {Unlabeled} - Class I Prospectus - SIMT Real Return Fund (Class I, Class F) Sheet http://www.sei.com/20230127/role/DocumentRiskReturnSummaryUnlabeledClassIProspectusSIMTRealReturnFundClassIClassF Risk/Return Summary- Class I Prospectus - SIMT Real Return Fund (Class I, Class F) 74 false false R223.htm 020221 - Disclosure - Risk/Return Detail Data {Elements} - Class I Prospectus - SIMT Real Return Fund (Class I, Class F) Sheet http://www.sei.com/20230127/role/DisclosureRiskReturnDetailDataElementsClassIProspectusSIMTRealReturnFundClassIClassF Risk/Return Detail Data- Class I Prospectus - SIMT Real Return Fund (Class I, Class F) 75 false true R224.htm 020222 - Document - Risk/Return Summary {Unlabeled} - Class Y Prospectus - SIMT Large Cap Fund (Class Y) Sheet http://www.sei.com/20230127/role/DocumentRiskReturnSummaryUnlabeledClassYProspectusSIMTLargeCapFundClassY Risk/Return Summary- Class Y Prospectus - SIMT Large Cap Fund (Class Y) 76 false false R229.htm 020227 - Disclosure - Risk/Return Detail Data {Elements} - Class Y Prospectus - SIMT Large Cap Fund (Class Y) Sheet http://www.sei.com/20230127/role/DisclosureRiskReturnDetailDataElementsClassYProspectusSIMTLargeCapFundClassY Risk/Return Detail Data- Class Y Prospectus - SIMT Large Cap Fund (Class Y) 77 false true R230.htm 020228 - Document - Risk/Return Summary {Unlabeled} - Class Y Prospectus - SIMT LARGE CAP VALUE FUND (Class Y) Sheet http://www.sei.com/20230127/role/DocumentRiskReturnSummaryUnlabeledClassYProspectusSIMTLARGECAPVALUEFUNDClassY Risk/Return Summary- Class Y Prospectus - SIMT LARGE CAP VALUE FUND (Class Y) 78 false false R235.htm 020233 - Disclosure - Risk/Return Detail Data {Elements} - Class Y Prospectus - SIMT LARGE CAP VALUE FUND (Class Y) Sheet http://www.sei.com/20230127/role/DisclosureRiskReturnDetailDataElementsClassYProspectusSIMTLARGECAPVALUEFUNDClassY Risk/Return Detail Data- Class Y Prospectus - SIMT LARGE CAP VALUE FUND (Class Y) 79 false true R236.htm 020234 - Document - Risk/Return Summary {Unlabeled} - Class Y Prospectus - SIMT LARGE CAP GROWTH FUND (Class Y) Sheet http://www.sei.com/20230127/role/DocumentRiskReturnSummaryUnlabeledClassYProspectusSIMTLARGECAPGROWTHFUNDClassY Risk/Return Summary- Class Y Prospectus - SIMT LARGE CAP GROWTH FUND (Class Y) 80 false false R241.htm 020239 - Disclosure - Risk/Return Detail Data {Elements} - Class Y Prospectus - SIMT LARGE CAP GROWTH FUND (Class Y) Sheet http://www.sei.com/20230127/role/DisclosureRiskReturnDetailDataElementsClassYProspectusSIMTLARGECAPGROWTHFUNDClassY Risk/Return Detail Data- Class Y Prospectus - SIMT LARGE CAP GROWTH FUND (Class Y) 81 false true R242.htm 020240 - Document - Risk/Return Summary {Unlabeled} - Class Y Prospectus - SIMT TAX-MANAGED LARGE CAP FUND (Class Y) Sheet http://www.sei.com/20230127/role/DocumentRiskReturnSummaryUnlabeledClassYProspectusSIMTTAXMANAGEDLARGECAPFUNDClassY Risk/Return Summary- Class Y Prospectus - SIMT TAX-MANAGED LARGE CAP FUND (Class Y) 82 false false R247.htm 020245 - Disclosure - Risk/Return Detail Data {Elements} - Class Y Prospectus - SIMT TAX-MANAGED LARGE CAP FUND (Class Y) Sheet http://www.sei.com/20230127/role/DisclosureRiskReturnDetailDataElementsClassYProspectusSIMTTAXMANAGEDLARGECAPFUNDClassY Risk/Return Detail Data- Class Y Prospectus - SIMT TAX-MANAGED LARGE CAP FUND (Class Y) 83 false true R248.htm 020246 - Document - Risk/Return Summary {Unlabeled} - Class Y Prospectus - SIMT Small Cap Fund (Class Y) Sheet http://www.sei.com/20230127/role/DocumentRiskReturnSummaryUnlabeledClassYProspectusSIMTSmallCapFundClassY Risk/Return Summary- Class Y Prospectus - SIMT Small Cap Fund (Class Y) 84 false false R253.htm 020251 - Disclosure - Risk/Return Detail Data {Elements} - Class Y Prospectus - SIMT Small Cap Fund (Class Y) Sheet http://www.sei.com/20230127/role/DisclosureRiskReturnDetailDataElementsClassYProspectusSIMTSmallCapFundClassY Risk/Return Detail Data- Class Y Prospectus - SIMT Small Cap Fund (Class Y) 85 false true R254.htm 020252 - Document - Risk/Return Summary {Unlabeled} - Class Y Prospectus - SIMT SMALL CAP VALUE FUND (Class Y) Sheet http://www.sei.com/20230127/role/DocumentRiskReturnSummaryUnlabeledClassYProspectusSIMTSMALLCAPVALUEFUNDClassY Risk/Return Summary- Class Y Prospectus - SIMT SMALL CAP VALUE FUND (Class Y) 86 false false R259.htm 020257 - Disclosure - Risk/Return Detail Data {Elements} - Class Y Prospectus - SIMT SMALL CAP VALUE FUND (Class Y) Sheet http://www.sei.com/20230127/role/DisclosureRiskReturnDetailDataElementsClassYProspectusSIMTSMALLCAPVALUEFUNDClassY Risk/Return Detail Data- Class Y Prospectus - SIMT SMALL CAP VALUE FUND (Class Y) 87 false true R260.htm 020258 - Document - Risk/Return Summary {Unlabeled} - Class Y Prospectus - SIMT SMALL CAP GROWTH FUND (Class Y) Sheet http://www.sei.com/20230127/role/DocumentRiskReturnSummaryUnlabeledClassYProspectusSIMTSMALLCAPGROWTHFUNDClassY Risk/Return Summary- Class Y Prospectus - SIMT SMALL CAP GROWTH FUND (Class Y) 88 false false R265.htm 020263 - Disclosure - Risk/Return Detail Data {Elements} - Class Y Prospectus - SIMT SMALL CAP GROWTH FUND (Class Y) Sheet http://www.sei.com/20230127/role/DisclosureRiskReturnDetailDataElementsClassYProspectusSIMTSMALLCAPGROWTHFUNDClassY Risk/Return Detail Data- Class Y Prospectus - SIMT SMALL CAP GROWTH FUND (Class Y) 89 false true R266.htm 020264 - Document - Risk/Return Summary {Unlabeled} - Class Y Prospectus - SIMT TAX-MANAGED SMALL/MID CAP FUND (Class Y) Sheet http://www.sei.com/20230127/role/DocumentRiskReturnSummaryUnlabeledClassYProspectusSIMTTAXMANAGEDSMALLMIDCAPFUNDClassY Risk/Return Summary- Class Y Prospectus - SIMT TAX-MANAGED SMALL/MID CAP FUND (Class Y) 90 false false R271.htm 020269 - Disclosure - Risk/Return Detail Data {Elements} - Class Y Prospectus - SIMT TAX-MANAGED SMALL/MID CAP FUND (Class Y) Sheet http://www.sei.com/20230127/role/DisclosureRiskReturnDetailDataElementsClassYProspectusSIMTTAXMANAGEDSMALLMIDCAPFUNDClassY Risk/Return Detail Data- Class Y Prospectus - SIMT TAX-MANAGED SMALL/MID CAP FUND (Class Y) 91 false true R272.htm 020270 - Document - Risk/Return Summary {Unlabeled} - Class Y Prospectus - SIMT MID CAP FUND (Class Y) Sheet http://www.sei.com/20230127/role/DocumentRiskReturnSummaryUnlabeledClassYProspectusSIMTMIDCAPFUNDClassY Risk/Return Summary- Class Y Prospectus - SIMT MID CAP FUND (Class Y) 92 false false R277.htm 020275 - Disclosure - Risk/Return Detail Data {Elements} - Class Y Prospectus - SIMT MID CAP FUND (Class Y) Sheet http://www.sei.com/20230127/role/DisclosureRiskReturnDetailDataElementsClassYProspectusSIMTMIDCAPFUNDClassY Risk/Return Detail Data- Class Y Prospectus - SIMT MID CAP FUND (Class Y) 93 false true R278.htm 020276 - Document - Risk/Return Summary {Unlabeled} - Class Y Prospectus - SIMT US MANAGED VOLATILITY FUND (Class Y) Sheet http://www.sei.com/20230127/role/DocumentRiskReturnSummaryUnlabeledClassYProspectusSIMTUSMANAGEDVOLATILITYFUNDClassY Risk/Return Summary- Class Y Prospectus - SIMT US MANAGED VOLATILITY FUND (Class Y) 94 false false R283.htm 020281 - Disclosure - Risk/Return Detail Data {Elements} - Class Y Prospectus - SIMT US MANAGED VOLATILITY FUND (Class Y) Sheet http://www.sei.com/20230127/role/DisclosureRiskReturnDetailDataElementsClassYProspectusSIMTUSMANAGEDVOLATILITYFUNDClassY Risk/Return Detail Data- Class Y Prospectus - SIMT US MANAGED VOLATILITY FUND (Class Y) 95 false true R284.htm 020282 - Document - Risk/Return Summary {Unlabeled} - Class Y Prospectus - SIMT GLOBAL MANAGED VOLATILITY FUND (Class Y) Sheet http://www.sei.com/20230127/role/DocumentRiskReturnSummaryUnlabeledClassYProspectusSIMTGLOBALMANAGEDVOLATILITYFUNDClassY Risk/Return Summary- Class Y Prospectus - SIMT GLOBAL MANAGED VOLATILITY FUND (Class Y) 96 false false R289.htm 020287 - Disclosure - Risk/Return Detail Data {Elements} - Class Y Prospectus - SIMT GLOBAL MANAGED VOLATILITY FUND (Class Y) Sheet http://www.sei.com/20230127/role/DisclosureRiskReturnDetailDataElementsClassYProspectusSIMTGLOBALMANAGEDVOLATILITYFUNDClassY Risk/Return Detail Data- Class Y Prospectus - SIMT GLOBAL MANAGED VOLATILITY FUND (Class Y) 97 false true R290.htm 020288 - Document - Risk/Return Summary {Unlabeled} - Class Y Prospectus - SIMT Tax-Managed Managed Volatility Fund (Class Y) Sheet http://www.sei.com/20230127/role/DocumentRiskReturnSummaryUnlabeledClassYProspectusSIMTTaxManagedManagedVolatilityFundClassY Risk/Return Summary- Class Y Prospectus - SIMT Tax-Managed Managed Volatility Fund (Class Y) 98 false false R295.htm 020293 - Disclosure - Risk/Return Detail Data {Elements} - Class Y Prospectus - SIMT Tax-Managed Managed Volatility Fund (Class Y) Sheet http://www.sei.com/20230127/role/DisclosureRiskReturnDetailDataElementsClassYProspectusSIMTTaxManagedManagedVolatilityFundClassY Risk/Return Detail Data- Class Y Prospectus - SIMT Tax-Managed Managed Volatility Fund (Class Y) 99 false true R296.htm 020294 - Document - Risk/Return Summary {Unlabeled} - Class Y Prospectus - SIMT Tax-Managed International Managed Volatility Fund (Class Y) Sheet http://www.sei.com/20230127/role/DocumentRiskReturnSummaryUnlabeledClassYProspectusSIMTTaxManagedInternationalManagedVolatilityFundClassY Risk/Return Summary- Class Y Prospectus - SIMT Tax-Managed International Managed Volatility Fund (Class Y) 100 false false R301.htm 020299 - Disclosure - Risk/Return Detail Data {Elements} - Class Y Prospectus - SIMT Tax-Managed International Managed Volatility Fund (Class Y) Sheet http://www.sei.com/20230127/role/DisclosureRiskReturnDetailDataElementsClassYProspectusSIMTTaxManagedInternationalManagedVolatilityFundClassY Risk/Return Detail Data- Class Y Prospectus - SIMT Tax-Managed International Managed Volatility Fund (Class Y) 101 false true R302.htm 020300 - Document - Risk/Return Summary {Unlabeled} - Class Y Prospectus - SIMT REAL ESTATE FUND (Class Y) Sheet http://www.sei.com/20230127/role/DocumentRiskReturnSummaryUnlabeledClassYProspectusSIMTREALESTATEFUNDClassY Risk/Return Summary- Class Y Prospectus - SIMT REAL ESTATE FUND (Class Y) 102 false false R307.htm 020305 - Disclosure - Risk/Return Detail Data {Elements} - Class Y Prospectus - SIMT REAL ESTATE FUND (Class Y) Sheet http://www.sei.com/20230127/role/DisclosureRiskReturnDetailDataElementsClassYProspectusSIMTREALESTATEFUNDClassY Risk/Return Detail Data- Class Y Prospectus - SIMT REAL ESTATE FUND (Class Y) 103 false true R308.htm 020306 - Document - Risk/Return Summary {Unlabeled} - Class Y Prospectus - SIMT CORE FIXED INCOME FUND (Class Y) Sheet http://www.sei.com/20230127/role/DocumentRiskReturnSummaryUnlabeledClassYProspectusSIMTCOREFIXEDINCOMEFUNDClassY Risk/Return Summary- Class Y Prospectus - SIMT CORE FIXED INCOME FUND (Class Y) 104 false false R313.htm 020311 - Disclosure - Risk/Return Detail Data {Elements} - Class Y Prospectus - SIMT CORE FIXED INCOME FUND (Class Y) Sheet http://www.sei.com/20230127/role/DisclosureRiskReturnDetailDataElementsClassYProspectusSIMTCOREFIXEDINCOMEFUNDClassY Risk/Return Detail Data- Class Y Prospectus - SIMT CORE FIXED INCOME FUND (Class Y) 105 false true R314.htm 020312 - Document - Risk/Return Summary {Unlabeled} - Class Y Prospectus - SIMT HIGH YIELD BOND FUND (Class Y) Sheet http://www.sei.com/20230127/role/DocumentRiskReturnSummaryUnlabeledClassYProspectusSIMTHIGHYIELDBONDFUNDClassY Risk/Return Summary- Class Y Prospectus - SIMT HIGH YIELD BOND FUND (Class Y) 106 false false R319.htm 020317 - Disclosure - Risk/Return Detail Data {Elements} - Class Y Prospectus - SIMT HIGH YIELD BOND FUND (Class Y) Sheet http://www.sei.com/20230127/role/DisclosureRiskReturnDetailDataElementsClassYProspectusSIMTHIGHYIELDBONDFUNDClassY Risk/Return Detail Data- Class Y Prospectus - SIMT HIGH YIELD BOND FUND (Class Y) 107 false true R320.htm 020318 - Document - Risk/Return Summary {Unlabeled} - Class Y Prospectus - SIMT Conservative Income Fund (Class Y) Sheet http://www.sei.com/20230127/role/DocumentRiskReturnSummaryUnlabeledClassYProspectusSIMTConservativeIncomeFundClassY Risk/Return Summary- Class Y Prospectus - SIMT Conservative Income Fund (Class Y) 108 false false R325.htm 020323 - Disclosure - Risk/Return Detail Data {Elements} - Class Y Prospectus - SIMT Conservative Income Fund (Class Y) Sheet http://www.sei.com/20230127/role/DisclosureRiskReturnDetailDataElementsClassYProspectusSIMTConservativeIncomeFundClassY Risk/Return Detail Data- Class Y Prospectus - SIMT Conservative Income Fund (Class Y) 109 false true R326.htm 020324 - Document - Risk/Return Summary {Unlabeled} - Class Y Prospectus - SIMT Tax-Free Conservative Income Fund (Class Y) Sheet http://www.sei.com/20230127/role/DocumentRiskReturnSummaryUnlabeledClassYProspectusSIMTTaxFreeConservativeIncomeFundClassY Risk/Return Summary- Class Y Prospectus - SIMT Tax-Free Conservative Income Fund (Class Y) 110 false false R331.htm 020329 - Disclosure - Risk/Return Detail Data {Elements} - Class Y Prospectus - SIMT Tax-Free Conservative Income Fund (Class Y) Sheet http://www.sei.com/20230127/role/DisclosureRiskReturnDetailDataElementsClassYProspectusSIMTTaxFreeConservativeIncomeFundClassY Risk/Return Detail Data- Class Y Prospectus - SIMT Tax-Free Conservative Income Fund (Class Y) 111 false true R332.htm 020330 - Document - Risk/Return Summary {Unlabeled} - Class Y Prospectus - SIMT Real Return Fund (Class Y) Sheet http://www.sei.com/20230127/role/DocumentRiskReturnSummaryUnlabeledClassYProspectusSIMTRealReturnFundClassY Risk/Return Summary- Class Y Prospectus - SIMT Real Return Fund (Class Y) 112 false false R337.htm 020335 - Disclosure - Risk/Return Detail Data {Elements} - Class Y Prospectus - SIMT Real Return Fund (Class Y) Sheet http://www.sei.com/20230127/role/DisclosureRiskReturnDetailDataElementsClassYProspectusSIMTRealReturnFundClassY Risk/Return Detail Data- Class Y Prospectus - SIMT Real Return Fund (Class Y) 113 false true R338.htm 020336 - Document - Risk/Return Summary {Unlabeled} - Class Y Prospectus - SIMT Dynamic Asset Allocation Fund (Class Y) Sheet http://www.sei.com/20230127/role/DocumentRiskReturnSummaryUnlabeledClassYProspectusSIMTDynamicAssetAllocationFundClassY Risk/Return Summary- Class Y Prospectus - SIMT Dynamic Asset Allocation Fund (Class Y) 114 false false R343.htm 020341 - Disclosure - Risk/Return Detail Data {Elements} - Class Y Prospectus - SIMT Dynamic Asset Allocation Fund (Class Y) Sheet http://www.sei.com/20230127/role/DisclosureRiskReturnDetailDataElementsClassYProspectusSIMTDynamicAssetAllocationFundClassY Risk/Return Detail Data- Class Y Prospectus - SIMT Dynamic Asset Allocation Fund (Class Y) 115 false true R344.htm 020342 - Document - Risk/Return Summary {Unlabeled} - Class Y Prospectus - SIMT Multi-Strategy Alternative Fund (Class Y) Sheet http://www.sei.com/20230127/role/DocumentRiskReturnSummaryUnlabeledClassYProspectusSIMTMultiStrategyAlternativeFundClassY Risk/Return Summary- Class Y Prospectus - SIMT Multi-Strategy Alternative Fund (Class Y) 116 false false R349.htm 020347 - Disclosure - Risk/Return Detail Data {Elements} - Class Y Prospectus - SIMT Multi-Strategy Alternative Fund (Class Y) Sheet http://www.sei.com/20230127/role/DisclosureRiskReturnDetailDataElementsClassYProspectusSIMTMultiStrategyAlternativeFundClassY Risk/Return Detail Data- Class Y Prospectus - SIMT Multi-Strategy Alternative Fund (Class Y) 117 false true R350.htm 020348 - Document - Risk/Return Summary {Unlabeled} - Class F Prospectus - SIMT MULTI-ASSET ACCUMULATION FUND (Class F) Sheet http://www.sei.com/20230127/role/DocumentRiskReturnSummaryUnlabeledClassFProspectusSIMTMULTIASSETACCUMULATIONFUNDClassF Risk/Return Summary- Class F Prospectus - SIMT MULTI-ASSET ACCUMULATION FUND (Class F) 118 false false R355.htm 020353 - Disclosure - Risk/Return Detail Data {Elements} - Class F Prospectus - SIMT MULTI-ASSET ACCUMULATION FUND (Class F) Sheet http://www.sei.com/20230127/role/DisclosureRiskReturnDetailDataElementsClassFProspectusSIMTMULTIASSETACCUMULATIONFUNDClassF Risk/Return Detail Data- Class F Prospectus - SIMT MULTI-ASSET ACCUMULATION FUND (Class F) 119 false true R356.htm 020354 - Document - Risk/Return Summary {Unlabeled} - Class F Prospectus - SIMT MULTI-ASSET INCOME FUND (Class F) Sheet http://www.sei.com/20230127/role/DocumentRiskReturnSummaryUnlabeledClassFProspectusSIMTMULTIASSETINCOMEFUNDClassF Risk/Return Summary- Class F Prospectus - SIMT MULTI-ASSET INCOME FUND (Class F) 120 false false R361.htm 020359 - Disclosure - Risk/Return Detail Data {Elements} - Class F Prospectus - SIMT MULTI-ASSET INCOME FUND (Class F) Sheet http://www.sei.com/20230127/role/DisclosureRiskReturnDetailDataElementsClassFProspectusSIMTMULTIASSETINCOMEFUNDClassF Risk/Return Detail Data- Class F Prospectus - SIMT MULTI-ASSET INCOME FUND (Class F) 121 false true R362.htm 020360 - Document - Risk/Return Summary {Unlabeled} - Class F Prospectus - SIMT MULTI-ASSET INFLATION MANAGED FUND (Class F) Sheet http://www.sei.com/20230127/role/DocumentRiskReturnSummaryUnlabeledClassFProspectusSIMTMULTIASSETINFLATIONMANAGEDFUNDClassF Risk/Return Summary- Class F Prospectus - SIMT MULTI-ASSET INFLATION MANAGED FUND (Class F) 122 false false R367.htm 020365 - Disclosure - Risk/Return Detail Data {Elements} - Class F Prospectus - SIMT MULTI-ASSET INFLATION MANAGED FUND (Class F) Sheet http://www.sei.com/20230127/role/DisclosureRiskReturnDetailDataElementsClassFProspectusSIMTMULTIASSETINFLATIONMANAGEDFUNDClassF Risk/Return Detail Data- Class F Prospectus - SIMT MULTI-ASSET INFLATION MANAGED FUND (Class F) 123 false true R368.htm 020366 - Document - Risk/Return Summary {Unlabeled} - Class F Prospectus - SIMT MULTI-ASSET CAPITAL STABILITY FUND (Class F) Sheet http://www.sei.com/20230127/role/DocumentRiskReturnSummaryUnlabeledClassFProspectusSIMTMULTIASSETCAPITALSTABILITYFUNDClassF Risk/Return Summary- Class F Prospectus - SIMT MULTI-ASSET CAPITAL STABILITY FUND (Class F) 124 false false R373.htm 020371 - Disclosure - Risk/Return Detail Data {Elements} - Class F Prospectus - SIMT MULTI-ASSET CAPITAL STABILITY FUND (Class F) Sheet http://www.sei.com/20230127/role/DisclosureRiskReturnDetailDataElementsClassFProspectusSIMTMULTIASSETCAPITALSTABILITYFUNDClassF Risk/Return Detail Data- Class F Prospectus - SIMT MULTI-ASSET CAPITAL STABILITY FUND (Class F) 125 false true R374.htm 020372 - Document - Risk/Return Summary {Unlabeled} - Class Y Prospectus - SIMT MULTI-ASSET ACCUMULATION FUND (Class Y) Sheet http://www.sei.com/20230127/role/DocumentRiskReturnSummaryUnlabeledClassYProspectusSIMTMULTIASSETACCUMULATIONFUNDClassY Risk/Return Summary- Class Y Prospectus - SIMT MULTI-ASSET ACCUMULATION FUND (Class Y) 126 false false R379.htm 020377 - Disclosure - Risk/Return Detail Data {Elements} - Class Y Prospectus - SIMT MULTI-ASSET ACCUMULATION FUND (Class Y) Sheet http://www.sei.com/20230127/role/DisclosureRiskReturnDetailDataElementsClassYProspectusSIMTMULTIASSETACCUMULATIONFUNDClassY Risk/Return Detail Data- Class Y Prospectus - SIMT MULTI-ASSET ACCUMULATION FUND (Class Y) 127 false true R380.htm 020378 - Document - Risk/Return Summary {Unlabeled} - Class Y Prospectus - SIMT MULTI-ASSET INCOME FUND (Class Y) Sheet http://www.sei.com/20230127/role/DocumentRiskReturnSummaryUnlabeledClassYProspectusSIMTMULTIASSETINCOMEFUNDClassY Risk/Return Summary- Class Y Prospectus - SIMT MULTI-ASSET INCOME FUND (Class Y) 128 false false R385.htm 020383 - Disclosure - Risk/Return Detail Data {Elements} - Class Y Prospectus - SIMT MULTI-ASSET INCOME FUND (Class Y) Sheet http://www.sei.com/20230127/role/DisclosureRiskReturnDetailDataElementsClassYProspectusSIMTMULTIASSETINCOMEFUNDClassY Risk/Return Detail Data- Class Y Prospectus - SIMT MULTI-ASSET INCOME FUND (Class Y) 129 false true R386.htm 020384 - Document - Risk/Return Summary {Unlabeled} - Class Y Prospectus - SIMT MULTI-ASSET INFLATION MANAGED FUND (Class Y) Sheet http://www.sei.com/20230127/role/DocumentRiskReturnSummaryUnlabeledClassYProspectusSIMTMULTIASSETINFLATIONMANAGEDFUNDClassY Risk/Return Summary- Class Y Prospectus - SIMT MULTI-ASSET INFLATION MANAGED FUND (Class Y) 130 false false R391.htm 020389 - Disclosure - Risk/Return Detail Data {Elements} - Class Y Prospectus - SIMT MULTI-ASSET INFLATION MANAGED FUND (Class Y) Sheet http://www.sei.com/20230127/role/DisclosureRiskReturnDetailDataElementsClassYProspectusSIMTMULTIASSETINFLATIONMANAGEDFUNDClassY Risk/Return Detail Data- Class Y Prospectus - SIMT MULTI-ASSET INFLATION MANAGED FUND (Class Y) 131 false true R392.htm 020390 - Document - Risk/Return Summary {Unlabeled} - Class Y Prospectus - SIMT MULTI-ASSET CAPITAL STABILITY FUND (Class Y) Sheet http://www.sei.com/20230127/role/DocumentRiskReturnSummaryUnlabeledClassYProspectusSIMTMULTIASSETCAPITALSTABILITYFUNDClassY Risk/Return Summary- Class Y Prospectus - SIMT MULTI-ASSET CAPITAL STABILITY FUND (Class Y) 132 false false R397.htm 020395 - Disclosure - Risk/Return Detail Data {Elements} - Class Y Prospectus - SIMT MULTI-ASSET CAPITAL STABILITY FUND (Class Y) Sheet http://www.sei.com/20230127/role/DisclosureRiskReturnDetailDataElementsClassYProspectusSIMTMULTIASSETCAPITALSTABILITYFUNDClassY Risk/Return Detail Data- Class Y Prospectus - SIMT MULTI-ASSET CAPITAL STABILITY FUND (Class Y) 133 false false R398.htm 040000 - Disclosure - Risk/Return Detail Data {Elements} Sheet http://xbrl.sec.gov/rr/role/RiskReturnDetailData Risk/Return Detail Data 134 false false All Reports Book All Reports tm2232084d1_485bpos.htm ck0000804239-20230127.xsd ck0000804239-20230127_cal.xml ck0000804239-20230127_def.xml ck0000804239-20230127_lab.xml ck0000804239-20230127_pre.xml tm2232084d1_ex99-bd46.htm tm2232084d1_ex99-bd76.htm tm2232084d1_ex99-bd81.htm tm2232084d1_ex99-bi.htm tm2232084d1_ex99-bj.htm tm2232084d1_ex99-bp1.htm tm2232084d1_ex99-bp10.htm tm2232084d1_ex99-bp13.htm tm2232084d1_ex99-bp15.htm tm2232084d1_ex99-bp18.htm tm2232084d1_ex99-bp2.htm tm2232084d1_ex99-bp20.htm tm2232084d1_ex99-bp21.htm tm2232084d1_ex99-bp28.htm tm2232084d1_ex99-bp3.htm tm2232084d1_ex99-bp31.htm tm2232084d1_ex99-bp34.htm tm2232084d1_ex99-bp35.htm tm2232084d1_ex99-bp37.htm tm2232084d1_ex99-bp38.htm tm2232084d1_ex99-bp4.htm tm2232084d1_ex99-bp41.htm tm2232084d1_ex99-bp44.htm tm2232084d1_ex99-bp45.htm tm2232084d1_ex99-bp47.htm tm2232084d1_ex99-bp48.htm tm2232084d1_ex99-bp49.htm tm2232084d1_ex99-bp5.htm tm2232084d1_ex99-bp6.htm tm2232084d1_ex99-bp9.htm j22320842_aa001.jpg j22320842_aa002.jpg j22320842_ac003.jpg j22320842_ba004.jpg j22320842_ba005.jpg j22320842_ba006.jpg j22320842_ba007.jpg j22320842_ba008.jpg j22320842_ba009.jpg j22320842_bc010.jpg j22320842_bc011.jpg j22320842_bc012.jpg j22320842_bc013.jpg j22320842_bc014.jpg j22320842_bc015.jpg j22320842_be016.jpg j22320842_be017.jpg j22320842_be018.jpg j22320842_be019.jpg j22320842_be020.jpg j22320842_be021.jpg j22320842_bg022.jpg j22320842_bg023.jpg j22320842_bg024.jpg j22320842_bg025.jpg j22320842_bg026.jpg j22320842_za027.jpg j22320843_ac001.jpg j22320843_ba002.jpg j22320843_ba003.jpg j22320843_ba004.jpg j22320843_ba005.jpg j22320843_bc006.jpg j22320843_bc007.jpg j22320843_bc008.jpg j22320843_bc009.jpg j22320843_bc010.jpg j22320843_be011.jpg j22320843_be012.jpg j22320843_be013.jpg j22320843_be014.jpg j22320843_be015.jpg j22320843_za016.jpg j22320844_ac001.jpg j22320844_ba002.jpg j22320844_ba003.jpg j22320844_ba004.jpg j22320844_ba005.jpg j22320844_bc006.jpg j22320844_bc007.jpg j22320844_bc008.jpg j22320844_bc009.jpg j22320844_be010.jpg j22320844_be011.jpg j22320844_be012.jpg j22320844_bg013.jpg j22320844_bg014.jpg j22320844_bg015.jpg j22320844_bg016.jpg j22320844_bg017.jpg j22320844_bi018.jpg j22320844_bi019.jpg j22320844_bi020.jpg j22320844_bi021.jpg j22320844_bi022.jpg j22320844_za023.jpg j22320845_ac001.jpg j22320845_ba002.jpg j22320845_ba003.jpg j22320845_bc004.jpg j22320845_bc005.jpg j22320845_za006.jpg j22320846_ac001.jpg j22320846_ba002.jpg j22320846_ba003.jpg j22320846_bc004.jpg j22320846_bc005.jpg j22320846_za006.jpg BarChart1.png BarChart2.png BarChart3.png BarChart4.png BarChart5.png BarChart6.png BarChart7.png BarChart8.png BarChart9.png BarChart10.png BarChart11.png BarChart12.png BarChart13.png BarChart14.png BarChart15.png BarChart16.png BarChart17.png BarChart18.png BarChart19.png BarChart20.png BarChart21.png BarChart22.png BarChart23.png BarChart24.png BarChart25.png BarChart26.png BarChart27.png BarChart28.png BarChart29.png BarChart30.png BarChart31.png BarChart32.png BarChart33.png BarChart34.png BarChart35.png BarChart36.png BarChart37.png BarChart38.png BarChart39.png BarChart40.png BarChart41.png BarChart42.png BarChart43.png BarChart44.png BarChart45.png BarChart46.png BarChart47.png BarChart48.png BarChart49.png BarChart50.png BarChart51.png BarChart52.png BarChart53.png BarChart54.png BarChart55.png BarChart56.png BarChart57.png BarChart58.png BarChart59.png BarChart60.png BarChart61.png BarChart62.png BarChart63.png BarChart64.png BarChart65.png BarChart66.png http://xbrl.sec.gov/dei/2022 http://xbrl.sec.gov/rr/2022 true true