 | ifrs-full:PropertyPlantAndEquipmentAbstract | parent-child | http://xbrl.ssm.com.my/role/ssm/rol_ssmt-fs-mfrs_2017-12-31/ssmt-fs-mfrs_2017-12-31_role-200200x |
 | ifrs-full:InvestmentPropertyAbstract | parent-child | http://xbrl.ssm.com.my/role/ssm/rol_ssmt-fs-mfrs_2017-12-31/ssmt-fs-mfrs_2017-12-31_role-200200x |
 | ssmt-mfrs:BiologicalAssetsAbstract | parent-child | http://xbrl.ssm.com.my/role/ssm/rol_ssmt-fs-mfrs_2017-12-31/ssmt-fs-mfrs_2017-12-31_role-200200x |
 | ifrs-full:IntangibleAssetsAndGoodwillAbstract | parent-child | http://xbrl.ssm.com.my/role/ssm/rol_ssmt-fs-mfrs_2017-12-31/ssmt-fs-mfrs_2017-12-31_role-200200x |
 | ssmt-mfrs:InvestmentsInSubsidiariesAbstract | parent-child | http://xbrl.ssm.com.my/role/ssm/rol_ssmt-fs-mfrs_2017-12-31/ssmt-fs-mfrs_2017-12-31_role-200200x |
 | ssmt-mfrs:InvestmentsInAssociatesAbstract | parent-child | http://xbrl.ssm.com.my/role/ssm/rol_ssmt-fs-mfrs_2017-12-31/ssmt-fs-mfrs_2017-12-31_role-200200x |
 | ssmt-mfrs:InvestmentsInJointVentureAbstract | parent-child | http://xbrl.ssm.com.my/role/ssm/rol_ssmt-fs-mfrs_2017-12-31/ssmt-fs-mfrs_2017-12-31_role-200200x |
 | ifrs-full:NoncurrentReceivablesAbstract | parent-child | http://xbrl.ssm.com.my/role/ssm/rol_ssmt-fs-mfrs_2017-12-31/ssmt-fs-mfrs_2017-12-31_role-200200x |
 | ssmt-mfrs:NoncurrentDerivativeFinancialAssetsAbstract | parent-child | http://xbrl.ssm.com.my/role/ssm/rol_ssmt-fs-mfrs_2017-12-31/ssmt-fs-mfrs_2017-12-31_role-200200x |
 | ssmt-mfrs:InventoriesAbstract | parent-child | http://xbrl.ssm.com.my/role/ssm/rol_ssmt-fs-mfrs_2017-12-31/ssmt-fs-mfrs_2017-12-31_role-200200x |
 | ifrs-full:TradeAndOtherCurrentReceivablesAbstract | parent-child | http://xbrl.ssm.com.my/role/ssm/rol_ssmt-fs-mfrs_2017-12-31/ssmt-fs-mfrs_2017-12-31_role-200200x |
 | ssmt-mfrs:CurrentDerivativeFinancialAssetsAbstract | parent-child | http://xbrl.ssm.com.my/role/ssm/rol_ssmt-fs-mfrs_2017-12-31/ssmt-fs-mfrs_2017-12-31_role-200200x |
 | ifrs-full:CashAndCashEquivalentsAbstract | parent-child | http://xbrl.ssm.com.my/role/ssm/rol_ssmt-fs-mfrs_2017-12-31/ssmt-fs-mfrs_2017-12-31_role-200200x |
 | ssmt-mfrs:IssuedCapitalAbstract | parent-child | http://xbrl.ssm.com.my/role/ssm/rol_ssmt-fs-mfrs_2017-12-31/ssmt-fs-mfrs_2017-12-31_role-200200x |
 | ifrs-full:OtherReservesAbstract | parent-child | http://xbrl.ssm.com.my/role/ssm/rol_ssmt-fs-mfrs_2017-12-31/ssmt-fs-mfrs_2017-12-31_role-200200x |
 | ssmt-mfrs:OtherComponentsOfEquityAbstract | parent-child | http://xbrl.ssm.com.my/role/ssm/rol_ssmt-fs-mfrs_2017-12-31/ssmt-fs-mfrs_2017-12-31_role-200200x |
 | ifrs-full:NoncurrentPortionOfNoncurrentBorrowingsByTypeAbstract | parent-child | http://xbrl.ssm.com.my/role/ssm/rol_ssmt-fs-mfrs_2017-12-31/ssmt-fs-mfrs_2017-12-31_role-200200x |
 | ssmt-mfrs:NoncurrentEmployeeBenefitLiabilitiesAbstract | parent-child | http://xbrl.ssm.com.my/role/ssm/rol_ssmt-fs-mfrs_2017-12-31/ssmt-fs-mfrs_2017-12-31_role-200200x |
 | ifrs-full:NoncurrentProvisionsAbstract | parent-child | http://xbrl.ssm.com.my/role/ssm/rol_ssmt-fs-mfrs_2017-12-31/ssmt-fs-mfrs_2017-12-31_role-200200x |
 | ifrs-full:NoncurrentPayablesAbstract | parent-child | http://xbrl.ssm.com.my/role/ssm/rol_ssmt-fs-mfrs_2017-12-31/ssmt-fs-mfrs_2017-12-31_role-200200x |
 | ssmt-mfrs:NoncurrentDerivativeFinancialLiabilitiesAbstract | parent-child | http://xbrl.ssm.com.my/role/ssm/rol_ssmt-fs-mfrs_2017-12-31/ssmt-fs-mfrs_2017-12-31_role-200200x |
 | ssmt-mfrs:CurrentBorrowingsAbstract | parent-child | http://xbrl.ssm.com.my/role/ssm/rol_ssmt-fs-mfrs_2017-12-31/ssmt-fs-mfrs_2017-12-31_role-200200x |
 | ssmt-mfrs:CurrentEmployeeBenefitLiabilitiesAbstract | parent-child | http://xbrl.ssm.com.my/role/ssm/rol_ssmt-fs-mfrs_2017-12-31/ssmt-fs-mfrs_2017-12-31_role-200200x |
 | ifrs-full:CurrentProvisionsAbstract | parent-child | http://xbrl.ssm.com.my/role/ssm/rol_ssmt-fs-mfrs_2017-12-31/ssmt-fs-mfrs_2017-12-31_role-200200x |
 | ifrs-full:TradeAndOtherCurrentPayablesAbstract | parent-child | http://xbrl.ssm.com.my/role/ssm/rol_ssmt-fs-mfrs_2017-12-31/ssmt-fs-mfrs_2017-12-31_role-200200x |
 | ssmt-mfrs:CurrentDerivativeFinancialLiabilitesAbstract | parent-child | http://xbrl.ssm.com.my/role/ssm/rol_ssmt-fs-mfrs_2017-12-31/ssmt-fs-mfrs_2017-12-31_role-200200x |
 | ssmt-mfrs:OtherNoncurrentAssetsAbstract | parent-child | http://xbrl.ssm.com.my/role/ssm/rol_ssmt-fs-mfrs_2017-12-31/ssmt-fs-mfrs_2017-12-31_role-200200x |
 | ifrs-full:PropertyPlantAndEquipmentAbstract | domain-member | http://xbrl.ssm.com.my/role/ssm/rol_ssmt-fs-mfrs_2017-12-31/ssmt-fs-mfrs_2017-12-31_role-210100 |
 | ifrs-full:InvestmentPropertyAbstract | domain-member | http://xbrl.ssm.com.my/role/ssm/rol_ssmt-fs-mfrs_2017-12-31/ssmt-fs-mfrs_2017-12-31_role-210100 |
 | ssmt-mfrs:BiologicalAssetsAbstract | domain-member | http://xbrl.ssm.com.my/role/ssm/rol_ssmt-fs-mfrs_2017-12-31/ssmt-fs-mfrs_2017-12-31_role-210100 |
 | ifrs-full:IntangibleAssetsAndGoodwillAbstract | domain-member | http://xbrl.ssm.com.my/role/ssm/rol_ssmt-fs-mfrs_2017-12-31/ssmt-fs-mfrs_2017-12-31_role-210100 |
 | ssmt-mfrs:InvestmentsInSubsidiariesAbstract | domain-member | http://xbrl.ssm.com.my/role/ssm/rol_ssmt-fs-mfrs_2017-12-31/ssmt-fs-mfrs_2017-12-31_role-210100 |
 | ssmt-mfrs:InvestmentsInAssociatesAbstract | domain-member | http://xbrl.ssm.com.my/role/ssm/rol_ssmt-fs-mfrs_2017-12-31/ssmt-fs-mfrs_2017-12-31_role-210100 |
 | ssmt-mfrs:InvestmentsInJointVentureAbstract | domain-member | http://xbrl.ssm.com.my/role/ssm/rol_ssmt-fs-mfrs_2017-12-31/ssmt-fs-mfrs_2017-12-31_role-210100 |
 | ifrs-full:NoncurrentReceivablesAbstract | domain-member | http://xbrl.ssm.com.my/role/ssm/rol_ssmt-fs-mfrs_2017-12-31/ssmt-fs-mfrs_2017-12-31_role-210100 |
 | ssmt-mfrs:NoncurrentDerivativeFinancialAssetsAbstract | domain-member | http://xbrl.ssm.com.my/role/ssm/rol_ssmt-fs-mfrs_2017-12-31/ssmt-fs-mfrs_2017-12-31_role-210100 |
 | ssmt-mfrs:InventoriesAbstract | domain-member | http://xbrl.ssm.com.my/role/ssm/rol_ssmt-fs-mfrs_2017-12-31/ssmt-fs-mfrs_2017-12-31_role-210100 |
 | ifrs-full:TradeAndOtherCurrentReceivablesAbstract | domain-member | http://xbrl.ssm.com.my/role/ssm/rol_ssmt-fs-mfrs_2017-12-31/ssmt-fs-mfrs_2017-12-31_role-210100 |
 | ssmt-mfrs:CurrentDerivativeFinancialAssetsAbstract | domain-member | http://xbrl.ssm.com.my/role/ssm/rol_ssmt-fs-mfrs_2017-12-31/ssmt-fs-mfrs_2017-12-31_role-210100 |
 | ifrs-full:CashAndCashEquivalentsAbstract | domain-member | http://xbrl.ssm.com.my/role/ssm/rol_ssmt-fs-mfrs_2017-12-31/ssmt-fs-mfrs_2017-12-31_role-210100 |
 | ssmt-mfrs:OtherNoncurrentAssetsAbstract | domain-member | http://xbrl.ssm.com.my/role/ssm/rol_ssmt-fs-mfrs_2017-12-31/ssmt-fs-mfrs_2017-12-31_role-210100 |
 | ssmt-mfrs:IssuedCapitalAbstract | domain-member | http://xbrl.ssm.com.my/role/ssm/rol_ssmt-fs-mfrs_2017-12-31/ssmt-fs-mfrs_2017-12-31_role-210100 |
 | ifrs-full:OtherReservesAbstract | domain-member | http://xbrl.ssm.com.my/role/ssm/rol_ssmt-fs-mfrs_2017-12-31/ssmt-fs-mfrs_2017-12-31_role-210100 |
 | ssmt-mfrs:OtherComponentsOfEquityAbstract | domain-member | http://xbrl.ssm.com.my/role/ssm/rol_ssmt-fs-mfrs_2017-12-31/ssmt-fs-mfrs_2017-12-31_role-210100 |
 | ifrs-full:NoncurrentPortionOfNoncurrentBorrowingsByTypeAbstract | domain-member | http://xbrl.ssm.com.my/role/ssm/rol_ssmt-fs-mfrs_2017-12-31/ssmt-fs-mfrs_2017-12-31_role-210100 |
 | ssmt-mfrs:NoncurrentEmployeeBenefitLiabilitiesAbstract | domain-member | http://xbrl.ssm.com.my/role/ssm/rol_ssmt-fs-mfrs_2017-12-31/ssmt-fs-mfrs_2017-12-31_role-210100 |
 | ifrs-full:NoncurrentProvisionsAbstract | domain-member | http://xbrl.ssm.com.my/role/ssm/rol_ssmt-fs-mfrs_2017-12-31/ssmt-fs-mfrs_2017-12-31_role-210100 |
 | ifrs-full:NoncurrentPayablesAbstract | domain-member | http://xbrl.ssm.com.my/role/ssm/rol_ssmt-fs-mfrs_2017-12-31/ssmt-fs-mfrs_2017-12-31_role-210100 |
 | ssmt-mfrs:NoncurrentDerivativeFinancialLiabilitiesAbstract | domain-member | http://xbrl.ssm.com.my/role/ssm/rol_ssmt-fs-mfrs_2017-12-31/ssmt-fs-mfrs_2017-12-31_role-210100 |
 | ssmt-mfrs:CurrentBorrowingsAbstract | domain-member | http://xbrl.ssm.com.my/role/ssm/rol_ssmt-fs-mfrs_2017-12-31/ssmt-fs-mfrs_2017-12-31_role-210100 |
 | ssmt-mfrs:CurrentEmployeeBenefitLiabilitiesAbstract | domain-member | http://xbrl.ssm.com.my/role/ssm/rol_ssmt-fs-mfrs_2017-12-31/ssmt-fs-mfrs_2017-12-31_role-210100 |
 | ifrs-full:CurrentProvisionsAbstract | domain-member | http://xbrl.ssm.com.my/role/ssm/rol_ssmt-fs-mfrs_2017-12-31/ssmt-fs-mfrs_2017-12-31_role-210100 |
 | ifrs-full:TradeAndOtherCurrentPayablesAbstract | domain-member | http://xbrl.ssm.com.my/role/ssm/rol_ssmt-fs-mfrs_2017-12-31/ssmt-fs-mfrs_2017-12-31_role-210100 |
 | ssmt-mfrs:CurrentDerivativeFinancialLiabilitesAbstract | domain-member | http://xbrl.ssm.com.my/role/ssm/rol_ssmt-fs-mfrs_2017-12-31/ssmt-fs-mfrs_2017-12-31_role-210100 |