3.25.4 html 1845 673 1 true 298 0 false 17 false false R1.htm 0000001 - Document - Cover Page Sheet http://www.sek.se/role/CoverPage Cover Page Cover 1 false false R2.htm 0000002 - Document - Audit Information Sheet http://www.sek.se/role/AuditInformation Audit Information Cover 2 false false R3.htm 9952151 - Statement - Consolidated Statement of Comprehensive Income Sheet http://www.sek.se/role/ConsolidatedStatementofComprehensiveIncome Consolidated Statement of Comprehensive Income Statements 3 false false R4.htm 9952152 - Statement - Consolidated Statement of Comprehensive Income (Parenthetical) Sheet http://www.sek.se/role/ConsolidatedStatementofComprehensiveIncomeParenthetical Consolidated Statement of Comprehensive Income (Parenthetical) Statements 4 false false R5.htm 9952153 - Statement - Consolidated Statement of Financial Position Sheet http://www.sek.se/role/ConsolidatedStatementofFinancialPosition Consolidated Statement of Financial Position Statements 5 false false R6.htm 9952154 - Statement - Consolidated Statement of Changes in Equity Sheet http://www.sek.se/role/ConsolidatedStatementofChangesinEquity Consolidated Statement of Changes in Equity Statements 6 false false R7.htm 9952155 - Statement - Statement of Cash Flows in the Consolidated Group Sheet http://www.sek.se/role/StatementofCashFlowsintheConsolidatedGroup Statement of Cash Flows in the Consolidated Group Statements 7 false false R8.htm 9952156 - Statement - Statement of Cash Flows in the Consolidated Group (Parenthetical) Sheet http://www.sek.se/role/StatementofCashFlowsintheConsolidatedGroupParenthetical Statement of Cash Flows in the Consolidated Group (Parenthetical) Statements 8 false false R9.htm 9952157 - Disclosure - Corporate information Sheet http://www.sek.se/role/Corporateinformation Corporate information Notes 9 false false R10.htm 9952158 - Disclosure - Significant accounting policies Sheet http://www.sek.se/role/Significantaccountingpolicies Significant accounting policies Notes 10 false false R11.htm 9952159 - Disclosure - Net interest income Sheet http://www.sek.se/role/Netinterestincome Net interest income Notes 11 false false R12.htm 9952160 - Disclosure - Net fee and commissions expense Sheet http://www.sek.se/role/Netfeeandcommissionsexpense Net fee and commissions expense Notes 12 false false R13.htm 9952161 - Disclosure - Net results of financial transactions Sheet http://www.sek.se/role/Netresultsoffinancialtransactions Net results of financial transactions Notes 13 false false R14.htm 9952162 - Disclosure - Personnel expenses Sheet http://www.sek.se/role/Personnelexpenses Personnel expenses Notes 14 false false R15.htm 9952163 - Disclosure - Other administrative expenses Sheet http://www.sek.se/role/Otheradministrativeexpenses Other administrative expenses Notes 15 false false R16.htm 9952164 - Disclosure - Tangible and intangible assets Sheet http://www.sek.se/role/Tangibleandintangibleassets Tangible and intangible assets Notes 16 false false R17.htm 9952165 - Disclosure - Leasing Sheet http://www.sek.se/role/Leasing Leasing Notes 17 false false R18.htm 9952166 - Disclosure - Impairments Sheet http://www.sek.se/role/Impairments Impairments Notes 18 false false R19.htm 9952167 - Disclosure - Taxes Sheet http://www.sek.se/role/Taxes Taxes Notes 19 false false R20.htm 9952168 - Disclosure - Loans and liquidity investments Sheet http://www.sek.se/role/Loansandliquidityinvestments Loans and liquidity investments Notes 20 false false R21.htm 9952169 - Disclosure - Classification of financial assets and liabilities Sheet http://www.sek.se/role/Classificationoffinancialassetsandliabilities Classification of financial assets and liabilities Notes 21 false false R22.htm 9952170 - Disclosure - Financial assets and liabilities at fair value Sheet http://www.sek.se/role/Financialassetsandliabilitiesatfairvalue Financial assets and liabilities at fair value Notes 22 false false R23.htm 9952171 - Disclosure - Derivatives and hedge accounting Sheet http://www.sek.se/role/Derivativesandhedgeaccounting Derivatives and hedge accounting Notes 23 false false R24.htm 9952172 - Disclosure - Shares in subsidiaries Sheet http://www.sek.se/role/Sharesinsubsidiaries Shares in subsidiaries Notes 24 false false R25.htm 9952173 - Disclosure - Other assets Sheet http://www.sek.se/role/Otherassets Other assets Notes 25 false false R26.htm 9952174 - Disclosure - Prepaid expenses and accrued revenues Sheet http://www.sek.se/role/Prepaidexpensesandaccruedrevenues Prepaid expenses and accrued revenues Notes 26 false false R27.htm 9952175 - Disclosure - Debt Sheet http://www.sek.se/role/Debt Debt Notes 27 false false R28.htm 9952176 - Disclosure - Other liabilities Sheet http://www.sek.se/role/Otherliabilities Other liabilities Notes 28 false false R29.htm 9952177 - Disclosure - Accrued expenses and prepaid revenues Sheet http://www.sek.se/role/Accruedexpensesandprepaidrevenues Accrued expenses and prepaid revenues Notes 29 false false R30.htm 9952178 - Disclosure - Provisions Sheet http://www.sek.se/role/Provisions Provisions Notes 30 false false R31.htm 9952179 - Disclosure - Equity Sheet http://www.sek.se/role/Equity Equity Notes 31 false false R32.htm 9952180 - Disclosure - Pledged assets and contingent liabilities Sheet http://www.sek.se/role/Pledgedassetsandcontingentliabilities Pledged assets and contingent liabilities Notes 32 false false R33.htm 9952181 - Disclosure - CIRR-system Sheet http://www.sek.se/role/CIRRsystem CIRR-system Notes 33 false false R34.htm 9952182 - Disclosure - Capital adequacy Sheet http://www.sek.se/role/Capitaladequacy Capital adequacy Notes 34 false false R35.htm 9952183 - Disclosure - Risk information Sheet http://www.sek.se/role/Riskinformation Risk information Notes 35 false false R36.htm 9952184 - Disclosure - Transactions with related parties Sheet http://www.sek.se/role/Transactionswithrelatedparties Transactions with related parties Notes 36 false false R37.htm 9952185 - Disclosure - Events after the reporting period Sheet http://www.sek.se/role/Eventsafterthereportingperiod Events after the reporting period Notes 37 false false R38.htm 9952186 - Disclosure - Risk and capital management Sheet http://www.sek.se/role/Riskandcapitalmanagement Risk and capital management Notes 38 false false R39.htm 995447 - Disclosure - Insider Trading Policies and Procedures Sheet http://xbrl.sec.gov/ecd/role/InsiderTradingPoliciesProc Insider Trading Policies and Procedures Notes 39 false false R40.htm 995550 - Disclosure - Cybersecurity Risk Management and Strategy Disclosure Sheet http://xbrl.sec.gov/cyd/role/CybersecurityRiskManagementAndStrategyDisclosure Cybersecurity Risk Management and Strategy Disclosure Notes 40 false false R41.htm 9955511 - Disclosure - Significant accounting policies (Policies) Sheet http://www.sek.se/role/SignificantaccountingpoliciesPolicies Significant accounting policies (Policies) Policies 41 false false R42.htm 9955512 - Disclosure - Net interest income (Tables) Sheet http://www.sek.se/role/NetinterestincomeTables Net interest income (Tables) Tables http://www.sek.se/role/Netinterestincome 42 false false R43.htm 9955513 - Disclosure - Net fee and commissions expense (Tables) Sheet http://www.sek.se/role/NetfeeandcommissionsexpenseTables Net fee and commissions expense (Tables) Tables http://www.sek.se/role/Netfeeandcommissionsexpense 43 false false R44.htm 9955514 - Disclosure - Net results of financial transactions (Tables) Sheet http://www.sek.se/role/NetresultsoffinancialtransactionsTables Net results of financial transactions (Tables) Tables http://www.sek.se/role/Netresultsoffinancialtransactions 44 false false R45.htm 9955515 - Disclosure - Personnel expenses (Tables) Sheet http://www.sek.se/role/PersonnelexpensesTables Personnel expenses (Tables) Tables http://www.sek.se/role/Personnelexpenses 45 false false R46.htm 9955516 - Disclosure - Other administrative expenses (Tables) Sheet http://www.sek.se/role/OtheradministrativeexpensesTables Other administrative expenses (Tables) Tables http://www.sek.se/role/Otheradministrativeexpenses 46 false false R47.htm 9955517 - Disclosure - Tangible and intangible assets (Tables) Sheet http://www.sek.se/role/TangibleandintangibleassetsTables Tangible and intangible assets (Tables) Tables http://www.sek.se/role/Tangibleandintangibleassets 47 false false R48.htm 9955518 - Disclosure - Leasing (Tables) Sheet http://www.sek.se/role/LeasingTables Leasing (Tables) Tables http://www.sek.se/role/Leasing 48 false false R49.htm 9955519 - Disclosure - Impairments (Tables) Sheet http://www.sek.se/role/ImpairmentsTables Impairments (Tables) Tables http://www.sek.se/role/Impairments 49 false false R50.htm 9955520 - Disclosure - Taxes (Tables) Sheet http://www.sek.se/role/TaxesTables Taxes (Tables) Tables http://www.sek.se/role/Taxes 50 false false R51.htm 9955521 - Disclosure - Loans and liquidity investments (Tables) Sheet http://www.sek.se/role/LoansandliquidityinvestmentsTables Loans and liquidity investments (Tables) Tables http://www.sek.se/role/Loansandliquidityinvestments 51 false false R52.htm 9955522 - Disclosure - Classification of financial assets and liabilities (Tables) Sheet http://www.sek.se/role/ClassificationoffinancialassetsandliabilitiesTables Classification of financial assets and liabilities (Tables) Tables http://www.sek.se/role/Classificationoffinancialassetsandliabilities 52 false false R53.htm 9955523 - Disclosure - Financial assets and liabilities at fair value (Tables) Sheet http://www.sek.se/role/FinancialassetsandliabilitiesatfairvalueTables Financial assets and liabilities at fair value (Tables) Tables http://www.sek.se/role/Financialassetsandliabilitiesatfairvalue 53 false false R54.htm 9955524 - Disclosure - Derivatives and hedge accounting (Tables) Sheet http://www.sek.se/role/DerivativesandhedgeaccountingTables Derivatives and hedge accounting (Tables) Tables http://www.sek.se/role/Derivativesandhedgeaccounting 54 false false R55.htm 9955525 - Disclosure - Shares in subsidiaries (Tables) Sheet http://www.sek.se/role/SharesinsubsidiariesTables Shares in subsidiaries (Tables) Tables http://www.sek.se/role/Sharesinsubsidiaries 55 false false R56.htm 9955526 - Disclosure - Other assets (Tables) Sheet http://www.sek.se/role/OtherassetsTables Other assets (Tables) Tables http://www.sek.se/role/Otherassets 56 false false R57.htm 9955527 - Disclosure - Prepaid expenses and accrued revenues (Tables) Sheet http://www.sek.se/role/PrepaidexpensesandaccruedrevenuesTables Prepaid expenses and accrued revenues (Tables) Tables http://www.sek.se/role/Prepaidexpensesandaccruedrevenues 57 false false R58.htm 9955528 - Disclosure - Debt (Tables) Sheet http://www.sek.se/role/DebtTables Debt (Tables) Tables http://www.sek.se/role/Debt 58 false false R59.htm 9955529 - Disclosure - Other liabilities (Tables) Sheet http://www.sek.se/role/OtherliabilitiesTables Other liabilities (Tables) Tables http://www.sek.se/role/Otherliabilities 59 false false R60.htm 9955530 - Disclosure - Accrued expenses and prepaid revenues (Tables) Sheet http://www.sek.se/role/AccruedexpensesandprepaidrevenuesTables Accrued expenses and prepaid revenues (Tables) Tables http://www.sek.se/role/Accruedexpensesandprepaidrevenues 60 false false R61.htm 9955531 - Disclosure - Provisions (Tables) Sheet http://www.sek.se/role/ProvisionsTables Provisions (Tables) Tables http://www.sek.se/role/Provisions 61 false false R62.htm 9955532 - Disclosure - Equity (Tables) Sheet http://www.sek.se/role/EquityTables Equity (Tables) Tables http://www.sek.se/role/Equity 62 false false R63.htm 9955533 - Disclosure - Pledged assets and contingent liabilities (Tables) Sheet http://www.sek.se/role/PledgedassetsandcontingentliabilitiesTables Pledged assets and contingent liabilities (Tables) Tables http://www.sek.se/role/Pledgedassetsandcontingentliabilities 63 false false R64.htm 9955534 - Disclosure - CIRR-system (Tables) Sheet http://www.sek.se/role/CIRRsystemTables CIRR-system (Tables) Tables http://www.sek.se/role/CIRRsystem 64 false false R65.htm 9955535 - Disclosure - Capital adequacy (Tables) Sheet http://www.sek.se/role/CapitaladequacyTables Capital adequacy (Tables) Tables http://www.sek.se/role/Capitaladequacy 65 false false R66.htm 9955536 - Disclosure - Risk information (Tables) Sheet http://www.sek.se/role/RiskinformationTables Risk information (Tables) Tables http://www.sek.se/role/Riskinformation 66 false false R67.htm 9955537 - Disclosure - Transactions with related parties (Tables) Sheet http://www.sek.se/role/TransactionswithrelatedpartiesTables Transactions with related parties (Tables) Tables http://www.sek.se/role/Transactionswithrelatedparties 67 false false R68.htm 9955538 - Disclosure - Risk and capital management (Tables) Sheet http://www.sek.se/role/RiskandcapitalmanagementTables Risk and capital management (Tables) Tables http://www.sek.se/role/Riskandcapitalmanagement 68 false false R69.htm 9955539 - Disclosure - Corporate information (Details) Sheet http://www.sek.se/role/CorporateinformationDetails Corporate information (Details) Details http://www.sek.se/role/Corporateinformation 69 false false R70.htm 9955540 - Disclosure - Significant accounting policies - Segment reporting (Details) Sheet http://www.sek.se/role/SignificantaccountingpoliciesSegmentreportingDetails Significant accounting policies - Segment reporting (Details) Details 70 false false R71.htm 9955541 - Disclosure - Significant accounting policies - Financial instruments (Details) Sheet http://www.sek.se/role/SignificantaccountingpoliciesFinancialinstrumentsDetails Significant accounting policies - Financial instruments (Details) Details 71 false false R72.htm 9955542 - Disclosure - Significant accounting policies - Fair value measurement (Details) Sheet http://www.sek.se/role/SignificantaccountingpoliciesFairvaluemeasurementDetails Significant accounting policies - Fair value measurement (Details) Details 72 false false R73.htm 9955543 - Disclosure - Significant accounting policies - Provisions for expected credit losses (Details) Sheet http://www.sek.se/role/SignificantaccountingpoliciesProvisionsforexpectedcreditlossesDetails Significant accounting policies - Provisions for expected credit losses (Details) Details 73 false false R74.htm 9955544 - Disclosure - Net interest income - Schedule of net interest income (Details) Sheet http://www.sek.se/role/NetinterestincomeScheduleofnetinterestincomeDetails Net interest income - Schedule of net interest income (Details) Details 74 false false R75.htm 9955545 - Disclosure - Net interest income - Geographical areas and product group (Details) Sheet http://www.sek.se/role/NetinterestincomeGeographicalareasandproductgroupDetails Net interest income - Geographical areas and product group (Details) Details 75 false false R76.htm 9955546 - Disclosure - Net fee and commissions expense (Details) Sheet http://www.sek.se/role/NetfeeandcommissionsexpenseDetails Net fee and commissions expense (Details) Details http://www.sek.se/role/NetfeeandcommissionsexpenseTables 76 false false R77.htm 9955547 - Disclosure - Net results of financial transactions (Details) Sheet http://www.sek.se/role/NetresultsoffinancialtransactionsDetails Net results of financial transactions (Details) Details http://www.sek.se/role/NetresultsoffinancialtransactionsTables 77 false false R78.htm 9955548 - Disclosure - Personnel expenses - Summary of total personnel expenses (Details) Sheet http://www.sek.se/role/PersonnelexpensesSummaryoftotalpersonnelexpensesDetails Personnel expenses - Summary of total personnel expenses (Details) Details 78 false false R79.htm 9955549 - Disclosure - Personnel expenses - Personnel expenses - Narrative (Details) Sheet http://www.sek.se/role/PersonnelexpensesPersonnelexpensesNarrativeDetails Personnel expenses - Personnel expenses - Narrative (Details) Details 79 false false R80.htm 9955550 - Disclosure - Personnel expenses - Remuneration and other benefits (Details) Sheet http://www.sek.se/role/PersonnelexpensesRemunerationandotherbenefitsDetails Personnel expenses - Remuneration and other benefits (Details) Details 80 false false R81.htm 9955551 - Disclosure - Personnel expenses - Total expenditure on remuneration - Narrative (Details) Sheet http://www.sek.se/role/PersonnelexpensesTotalexpenditureonremunerationNarrativeDetails Personnel expenses - Total expenditure on remuneration - Narrative (Details) Details 81 false false R82.htm 9955552 - Disclosure - Personnel expenses - Pension (Details) Sheet http://www.sek.se/role/PersonnelexpensesPensionDetails Personnel expenses - Pension (Details) Details 82 false false R83.htm 9955553 - Disclosure - Personnel expenses - Defined benefit pension (Details) Sheet http://www.sek.se/role/PersonnelexpensesDefinedbenefitpensionDetails Personnel expenses - Defined benefit pension (Details) Details 83 false false R84.htm 9955554 - Disclosure - Personnel expenses - Plan assets (Details) Sheet http://www.sek.se/role/PersonnelexpensesPlanassetsDetails Personnel expenses - Plan assets (Details) Details 84 false false R85.htm 9955555 - Disclosure - Personnel expenses - Actuarial assumptions (Details) Sheet http://www.sek.se/role/PersonnelexpensesActuarialassumptionsDetails Personnel expenses - Actuarial assumptions (Details) Details 85 false false R86.htm 9955556 - Disclosure - Personnel expenses - Sensitivity analysis of essential assumptions (Details) Sheet http://www.sek.se/role/PersonnelexpensesSensitivityanalysisofessentialassumptionsDetails Personnel expenses - Sensitivity analysis of essential assumptions (Details) Details 86 false false R87.htm 9955557 - Disclosure - Personnel expenses - Reconciliation of pension liabilities (Details) Sheet http://www.sek.se/role/PersonnelexpensesReconciliationofpensionliabilitiesDetails Personnel expenses - Reconciliation of pension liabilities (Details) Details 87 false false R88.htm 9955558 - Disclosure - Personnel expenses - Pensions - Narrative (Details) Sheet http://www.sek.se/role/PersonnelexpensesPensionsNarrativeDetails Personnel expenses - Pensions - Narrative (Details) Details 88 false false R89.htm 9955559 - Disclosure - Personnel expenses - Average number of employees (Details) Sheet http://www.sek.se/role/PersonnelexpensesAveragenumberofemployeesDetails Personnel expenses - Average number of employees (Details) Details 89 false false R90.htm 9955560 - Disclosure - Personnel expenses - Employee equality and diversity (Details) Sheet http://www.sek.se/role/PersonnelexpensesEmployeeequalityanddiversityDetails Personnel expenses - Employee equality and diversity (Details) Details 90 false false R91.htm 9955561 - Disclosure - Other administrative expenses - Schedule of other administrative expenses (Details) Sheet http://www.sek.se/role/OtheradministrativeexpensesScheduleofotheradministrativeexpensesDetails Other administrative expenses - Schedule of other administrative expenses (Details) Details 91 false false R92.htm 9955562 - Disclosure - Other administrative expenses - Remuneration to auditors (Details) Sheet http://www.sek.se/role/OtheradministrativeexpensesRemunerationtoauditorsDetails Other administrative expenses - Remuneration to auditors (Details) Details 92 false false R93.htm 9955563 - Disclosure - Tangible and intangible assets - Narrative (Details) Sheet http://www.sek.se/role/TangibleandintangibleassetsNarrativeDetails Tangible and intangible assets - Narrative (Details) Details 93 false false R94.htm 9955564 - Disclosure - Tangible and intangible assets -Schedule of reconciliation of changes in tangible and intangible assets (Details) Sheet http://www.sek.se/role/TangibleandintangibleassetsScheduleofreconciliationofchangesintangibleandintangibleassetsDetails Tangible and intangible assets -Schedule of reconciliation of changes in tangible and intangible assets (Details) Details 94 false false R95.htm 9955565 - Disclosure - Leasing - Narrative (Details) Sheet http://www.sek.se/role/LeasingNarrativeDetails Leasing - Narrative (Details) Details 95 false false R96.htm 9955566 - Disclosure - Leasing - Right of use asset (Details) Sheet http://www.sek.se/role/LeasingRightofuseassetDetails Leasing - Right of use asset (Details) Details 96 false false R97.htm 9955567 - Disclosure - Leasing - Accounted for in profit or loss (Details) Sheet http://www.sek.se/role/LeasingAccountedforinprofitorlossDetails Leasing - Accounted for in profit or loss (Details) Details 97 false false R98.htm 9955568 - Disclosure - Leasing - Lease liability (Details) Sheet http://www.sek.se/role/LeasingLeaseliabilityDetails Leasing - Lease liability (Details) Details 98 false false R99.htm 9955569 - Disclosure - Leasing - Contractual flows of lease liability and costs (Details) Sheet http://www.sek.se/role/LeasingContractualflowsofleaseliabilityandcostsDetails Leasing - Contractual flows of lease liability and costs (Details) Details 99 false false R100.htm 9955570 - Disclosure - Leasing - Future lease payments receivable (Details) Sheet http://www.sek.se/role/LeasingFutureleasepaymentsreceivableDetails Leasing - Future lease payments receivable (Details) Details 100 false false R101.htm 9955571 - Disclosure - Impairments - Schedule of impairment (Details) Sheet http://www.sek.se/role/ImpairmentsScheduleofimpairmentDetails Impairments - Schedule of impairment (Details) Details 101 false false R102.htm 9955572 - Disclosure - Impairments - Loss Allowance (Details) Sheet http://www.sek.se/role/ImpairmentsLossAllowanceDetails Impairments - Loss Allowance (Details) Details 102 false false R103.htm 9955573 - Disclosure - Impairments - Reconciliations (Details) Sheet http://www.sek.se/role/ImpairmentsReconciliationsDetails Impairments - Reconciliations (Details) Details 103 false false R104.htm 9955574 - Disclosure - Impairments - Narrative (Details) Sheet http://www.sek.se/role/ImpairmentsNarrativeDetails Impairments - Narrative (Details) Details 104 false false R105.htm 9955575 - Disclosure - Impairments - Loan credit quality (Details) Sheet http://www.sek.se/role/ImpairmentsLoancreditqualityDetails Impairments - Loan credit quality (Details) Details 105 false false R106.htm 9955576 - Disclosure - Taxes - Schedule of income taxes (Details) Sheet http://www.sek.se/role/TaxesScheduleofincometaxesDetails Taxes - Schedule of income taxes (Details) Details 106 false false R107.htm 9955577 - Disclosure - Taxes - Reconciliation of effective tax rate (Details) Sheet http://www.sek.se/role/TaxesReconciliationofeffectivetaxrateDetails Taxes - Reconciliation of effective tax rate (Details) Details 107 false false R108.htm 9955578 - Disclosure - Taxes - Deferred tax assets and liabilities (Details) Sheet http://www.sek.se/role/TaxesDeferredtaxassetsandliabilitiesDetails Taxes - Deferred tax assets and liabilities (Details) Details 108 false false R109.htm 9955579 - Disclosure - Taxes - Change in deferred taxes (Details) Sheet http://www.sek.se/role/TaxesChangeindeferredtaxesDetails Taxes - Change in deferred taxes (Details) Details 109 false false R110.htm 9955580 - Disclosure - Loans and liquidity investments - Schedule of loans and liquidity investments (Details) Sheet http://www.sek.se/role/LoansandliquidityinvestmentsScheduleofloansandliquidityinvestmentsDetails Loans and liquidity investments - Schedule of loans and liquidity investments (Details) Details 110 false false R111.htm 9955581 - Disclosure - Loans and liquidity investments - Difference between book value and amount required to be paid at maturity (Details) Sheet http://www.sek.se/role/LoansandliquidityinvestmentsDifferencebetweenbookvalueandamountrequiredtobepaidatmaturityDetails Loans and liquidity investments - Difference between book value and amount required to be paid at maturity (Details) Details 111 false false R112.htm 9955582 - Disclosure - Loans and liquidity investments - Outstanding loans as per business area (Details) Sheet http://www.sek.se/role/LoansandliquidityinvestmentsOutstandingloansasperbusinessareaDetails Loans and liquidity investments - Outstanding loans as per business area (Details) Details 112 false false R113.htm 9955583 - Disclosure - Classification of financial assets and liabilities - Financial assets (Details) Sheet http://www.sek.se/role/ClassificationoffinancialassetsandliabilitiesFinancialassetsDetails Classification of financial assets and liabilities - Financial assets (Details) Details 113 false false R114.htm 9955584 - Disclosure - Classification of financial assets and liabilities - Financial liabilities (Details) Sheet http://www.sek.se/role/ClassificationoffinancialassetsandliabilitiesFinancialliabilitiesDetails Classification of financial assets and liabilities - Financial liabilities (Details) Details 114 false false R115.htm 9955585 - Disclosure - Financial assets and liabilities at fair value - Financial assets and liabilities at fair value (Details) Sheet http://www.sek.se/role/FinancialassetsandliabilitiesatfairvalueFinancialassetsandliabilitiesatfairvalueDetails Financial assets and liabilities at fair value - Financial assets and liabilities at fair value (Details) Details 115 false false R116.htm 9955586 - Disclosure - Financial assets and liabilities at fair value - Financial assets & liabilities reported at amortized cost in fair value hierarchy (Details) Sheet http://www.sek.se/role/FinancialassetsandliabilitiesatfairvalueFinancialassetsliabilitiesreportedatamortizedcostinfairvaluehierarchyDetails Financial assets and liabilities at fair value - Financial assets & liabilities reported at amortized cost in fair value hierarchy (Details) Details 116 false false R117.htm 9955587 - Disclosure - Financial assets and liabilities at fair value - Financial assets & liabilities reported at fair value in fair value hierarchy (Details) Sheet http://www.sek.se/role/FinancialassetsandliabilitiesatfairvalueFinancialassetsliabilitiesreportedatfairvalueinfairvaluehierarchyDetails Financial assets and liabilities at fair value - Financial assets & liabilities reported at fair value in fair value hierarchy (Details) Details 117 false false R118.htm 9955588 - Disclosure - Financial assets and liabilities at fair value - Narrative (Details) Sheet http://www.sek.se/role/FinancialassetsandliabilitiesatfairvalueNarrativeDetails Financial assets and liabilities at fair value - Narrative (Details) Details 118 false false R119.htm 9955589 - Disclosure - Financial assets and liabilities at fair value - Financial assets and liabilities at fair value in level 3 (Details) Sheet http://www.sek.se/role/FinancialassetsandliabilitiesatfairvalueFinancialassetsandliabilitiesatfairvalueinlevel3Details Financial assets and liabilities at fair value - Financial assets and liabilities at fair value in level 3 (Details) Details 119 false false R120.htm 9955590 - Disclosure - Financial assets and liabilities at fair value - Assets and liabilities Sensitivity analysis - level 3 (Details) Sheet http://www.sek.se/role/FinancialassetsandliabilitiesatfairvalueAssetsandliabilitiesSensitivityanalysislevel3Details Financial assets and liabilities at fair value - Assets and liabilities Sensitivity analysis - level 3 (Details) Details 120 false false R121.htm 9955591 - Disclosure - Financial assets and liabilities at fair value - Fair value related to credit risk (Details) Sheet http://www.sek.se/role/FinancialassetsandliabilitiesatfairvalueFairvaluerelatedtocreditriskDetails Financial assets and liabilities at fair value - Fair value related to credit risk (Details) Details 121 false false R122.htm 9955592 - Disclosure - Derivatives and hedge accounting - Schedule of derivatives (Details) Sheet http://www.sek.se/role/DerivativesandhedgeaccountingScheduleofderivativesDetails Derivatives and hedge accounting - Schedule of derivatives (Details) Details 122 false false R123.htm 9955593 - Disclosure - Derivatives and hedge accounting - Maturity analysis (Details) Sheet http://www.sek.se/role/DerivativesandhedgeaccountingMaturityanalysisDetails Derivatives and hedge accounting - Maturity analysis (Details) Details 123 false false R124.htm 9955594 - Disclosure - Derivatives and hedge accounting - Carrying amount of hedged items in fair value hedges (Details) Sheet http://www.sek.se/role/DerivativesandhedgeaccountingCarryingamountofhedgeditemsinfairvaluehedgesDetails Derivatives and hedge accounting - Carrying amount of hedged items in fair value hedges (Details) Details 124 false false R125.htm 9955595 - Disclosure - Derivatives and hedge accounting - Hedge ineffectiveness (Details) Sheet http://www.sek.se/role/DerivativesandhedgeaccountingHedgeineffectivenessDetails Derivatives and hedge accounting - Hedge ineffectiveness (Details) Details 125 false false R126.htm 9955596 - Disclosure - Derivatives and hedge accounting - Cash flow hedge reserve (Details) Sheet http://www.sek.se/role/DerivativesandhedgeaccountingCashflowhedgereserveDetails Derivatives and hedge accounting - Cash flow hedge reserve (Details) Details 126 false false R127.htm 9955597 - Disclosure - Derivatives and hedge accounting - Offsetting (Details) Sheet http://www.sek.se/role/DerivativesandhedgeaccountingOffsettingDetails Derivatives and hedge accounting - Offsetting (Details) Details 127 false false R128.htm 9955598 - Disclosure - Shares in subsidiaries (Details) Sheet http://www.sek.se/role/SharesinsubsidiariesDetails Shares in subsidiaries (Details) Details http://www.sek.se/role/SharesinsubsidiariesTables 128 false false R129.htm 9955599 - Disclosure - Other assets (Details) Sheet http://www.sek.se/role/OtherassetsDetails Other assets (Details) Details http://www.sek.se/role/OtherassetsTables 129 false false R130.htm 9955600 - Disclosure - Prepaid expenses and accrued revenues (Details) Sheet http://www.sek.se/role/PrepaidexpensesandaccruedrevenuesDetails Prepaid expenses and accrued revenues (Details) Details http://www.sek.se/role/PrepaidexpensesandaccruedrevenuesTables 130 false false R131.htm 9955601 - Disclosure - Debt - Schedule of debt (Details) Sheet http://www.sek.se/role/DebtScheduleofdebtDetails Debt - Schedule of debt (Details) Details 131 false false R132.htm 9955602 - Disclosure - Debt - borrowing programs (Details) Sheet http://www.sek.se/role/DebtborrowingprogramsDetails Debt - borrowing programs (Details) Details 132 false false R133.htm 9955603 - Disclosure - Debt - Liabilities in financing activities (Details) Sheet http://www.sek.se/role/DebtLiabilitiesinfinancingactivitiesDetails Debt - Liabilities in financing activities (Details) Details 133 false false R134.htm 9955604 - Disclosure - Other liabilities (Details) Sheet http://www.sek.se/role/OtherliabilitiesDetails Other liabilities (Details) Details http://www.sek.se/role/OtherliabilitiesTables 134 false false R135.htm 9955605 - Disclosure - Accrued expenses and prepaid revenues (Details) Sheet http://www.sek.se/role/AccruedexpensesandprepaidrevenuesDetails Accrued expenses and prepaid revenues (Details) Details http://www.sek.se/role/AccruedexpensesandprepaidrevenuesTables 135 false false R136.htm 9955606 - Disclosure - Provisions (Details) Sheet http://www.sek.se/role/ProvisionsDetails Provisions (Details) Details http://www.sek.se/role/ProvisionsTables 136 false false R137.htm 9955607 - Disclosure - Equity - Components of Equity (Details) Sheet http://www.sek.se/role/EquityComponentsofEquityDetails Equity - Components of Equity (Details) Details 137 false false R138.htm 9955608 - Disclosure - Equity - Proposal for distribution of profits (Details) Sheet http://www.sek.se/role/EquityProposalfordistributionofprofitsDetails Equity - Proposal for distribution of profits (Details) Details 138 false false R139.htm 9955609 - Disclosure - Pledged assets and contingent liabilities (Details) Sheet http://www.sek.se/role/PledgedassetsandcontingentliabilitiesDetails Pledged assets and contingent liabilities (Details) Details http://www.sek.se/role/PledgedassetsandcontingentliabilitiesTables 139 false false R140.htm 9955610 - Disclosure - CIRR-System - Narrative (Details) Sheet http://www.sek.se/role/CIRRSystemNarrativeDetails CIRR-System - Narrative (Details) Details 140 false false R141.htm 9955611 - Disclosure - CIRR-system - Subclassifications of financial information (Details) Sheet http://www.sek.se/role/CIRRsystemSubclassificationsoffinancialinformationDetails CIRR-system - Subclassifications of financial information (Details) Details 141 false false R142.htm 9955612 - Disclosure - Capital adequacy - Capital adequacy (Details) Sheet http://www.sek.se/role/CapitaladequacyCapitaladequacyDetails Capital adequacy - Capital adequacy (Details) Details 142 false false R143.htm 9955613 - Disclosure - Capital adequacy - Leverage ratio (Details) Sheet http://www.sek.se/role/CapitaladequacyLeverageratioDetails Capital adequacy - Leverage ratio (Details) Details 143 false false R144.htm 9955614 - Disclosure - Capital adequacy - Own funds (Details) Sheet http://www.sek.se/role/CapitaladequacyOwnfundsDetails Capital adequacy - Own funds (Details) Details 144 false false R145.htm 9955615 - Disclosure - Capital adequacy - Minimum capital requirements exclusive of buffers (Details) Sheet http://www.sek.se/role/CapitaladequacyMinimumcapitalrequirementsexclusiveofbuffersDetails Capital adequacy - Minimum capital requirements exclusive of buffers (Details) Details 145 false false R146.htm 9955616 - Disclosure - Capital adequacy - Credit risk by PD grade (Details) Sheet http://www.sek.se/role/CapitaladequacyCreditriskbyPDgradeDetails Capital adequacy - Credit risk by PD grade (Details) Details 146 false false R147.htm 9955617 - Disclosure - Capital adequacy - Narrative (Details) Sheet http://www.sek.se/role/CapitaladequacyNarrativeDetails Capital adequacy - Narrative (Details) Details 147 false false R148.htm 9955618 - Disclosure - Capital adequacy - Internally assessed economic capital excl. buffer (Details) Sheet http://www.sek.se/role/CapitaladequacyInternallyassessedeconomiccapitalexclbufferDetails Capital adequacy - Internally assessed economic capital excl. buffer (Details) Details 148 false false R149.htm 9955619 - Disclosure - Risk information - Narrative (Details) Sheet http://www.sek.se/role/RiskinformationNarrativeDetails Risk information - Narrative (Details) Details 149 false false R150.htm 9955620 - Disclosure - Risk information - Maximum exposure to credit risk (Details) Sheet http://www.sek.se/role/RiskinformationMaximumexposuretocreditriskDetails Risk information - Maximum exposure to credit risk (Details) Details 150 false false R151.htm 9955621 - Disclosure - Risk information - Credit exposure (Details) Sheet http://www.sek.se/role/RiskinformationCreditexposureDetails Risk information - Credit exposure (Details) Details 151 false false R152.htm 9955622 - Disclosure - Risk information - Net exposure (Details) Sheet http://www.sek.se/role/RiskinformationNetexposureDetails Risk information - Net exposure (Details) Details 152 false false R153.htm 9955623 - Disclosure - Risk information - Total net exposures (Details) Sheet http://www.sek.se/role/RiskinformationTotalnetexposuresDetails Risk information - Total net exposures (Details) Details 153 false false R154.htm 9955624 - Disclosure - Risk information - Gross exposure by region and class (Details) Sheet http://www.sek.se/role/RiskinformationGrossexposurebyregionandclassDetails Risk information - Gross exposure by region and class (Details) Details 154 false false R155.htm 9955625 - Disclosure - Risk information - Net exposure by region and class (Details) Sheet http://www.sek.se/role/RiskinformationNetexposurebyregionandclassDetails Risk information - Net exposure by region and class (Details) Details 155 false false R156.htm 9955626 - Disclosure - Risk information - Effect of credit risk mitigation (Details) Sheet http://www.sek.se/role/RiskinformationEffectofcreditriskmitigationDetails Risk information - Effect of credit risk mitigation (Details) Details 156 false false R157.htm 9955627 - Disclosure - Risk information - Gross exposures European countries, excluding Sweden by exposure classes (Details) Sheet http://www.sek.se/role/RiskinformationGrossexposuresEuropeancountriesexcludingSwedenbyexposureclassesDetails Risk information - Gross exposures European countries, excluding Sweden by exposure classes (Details) Details 157 false false R158.htm 9955628 - Disclosure - Risk information - Net exposures European countries, excluding Sweden by exposure classes (Details) Sheet http://www.sek.se/role/RiskinformationNetexposuresEuropeancountriesexcludingSwedenbyexposureclassesDetails Risk information - Net exposures European countries, excluding Sweden by exposure classes (Details) Details 158 false false R159.htm 9955629 - Disclosure - Risk information - Corporate exposures by industry (GICS) (Details) Sheet http://www.sek.se/role/RiskinformationCorporateexposuresbyindustryGICSDetails Risk information - Corporate exposures by industry (GICS) (Details) Details 159 false false R160.htm 9955630 - Disclosure - Risk information - Market risk (Details) Sheet http://www.sek.se/role/RiskinformationMarketriskDetails Risk information - Market risk (Details) Details 160 false false R161.htm 9955631 - Disclosure - Risk information - Impact of one percentage point change in market interest rate (Details) Sheet http://www.sek.se/role/RiskinformationImpactofonepercentagepointchangeinmarketinterestrateDetails Risk information - Impact of one percentage point change in market interest rate (Details) Details 161 false false R162.htm 9955632 - Disclosure - Risk information - Foreign currency position (Details) Sheet http://www.sek.se/role/RiskinformationForeigncurrencypositionDetails Risk information - Foreign currency position (Details) Details 162 false false R163.htm 9955633 - Disclosure - Risk information - Assets and liabilities in foreign currencies (Details) Sheet http://www.sek.se/role/RiskinformationAssetsandliabilitiesinforeigncurrenciesDetails Risk information - Assets and liabilities in foreign currencies (Details) Details 163 false false R164.htm 9955634 - Disclosure - Risk information - Liquidity reserve (Details) Sheet http://www.sek.se/role/RiskinformationLiquidityreserveDetails Risk information - Liquidity reserve (Details) Details 164 false false R165.htm 9955635 - Disclosure - Risk information - Liquidity investments - Remaining maturity (Details) Sheet http://www.sek.se/role/RiskinformationLiquidityinvestmentsRemainingmaturityDetails Risk information - Liquidity investments - Remaining maturity (Details) Details 165 false false R166.htm 9955636 - Disclosure - Risk information - Key figures for liquidity risk (Details) Sheet http://www.sek.se/role/RiskinformationKeyfiguresforliquidityriskDetails Risk information - Key figures for liquidity risk (Details) Details 166 false false R167.htm 9955637 - Disclosure - Risk Information - Liquidity investments - By exposure type (Details) Sheet http://www.sek.se/role/RiskInformationLiquidityinvestmentsByexposuretypeDetails Risk Information - Liquidity investments - By exposure type (Details) Details 167 false false R168.htm 9955638 - Disclosure - Risk information - Contractual flows (Details) Sheet http://www.sek.se/role/RiskinformationContractualflowsDetails Risk information - Contractual flows (Details) Details 168 false false R169.htm 9955639 - Disclosure - Transactions with related parties - Narrative (Details) Sheet http://www.sek.se/role/TransactionswithrelatedpartiesNarrativeDetails Transactions with related parties - Narrative (Details) Details 169 false false R170.htm 9955640 - Disclosure - Transactions with related parties - Summarizes Consolidated Group's transactions with related parties (Details) Sheet http://www.sek.se/role/TransactionswithrelatedpartiesSummarizesConsolidatedGroupstransactionswithrelatedpartiesDetails Transactions with related parties - Summarizes Consolidated Group's transactions with related parties (Details) Details 170 false false R171.htm 9955641 - Disclosure - Risk and capital management (Details) Sheet http://www.sek.se/role/RiskandcapitalmanagementDetails Risk and capital management (Details) Details http://www.sek.se/role/RiskandcapitalmanagementTables 171 false false All Reports Book All Reports sek-20251231.htm sek-20251231.xsd sek-20251231_cal.xml sek-20251231_def.xml sek-20251231_lab.xml sek-20251231_pre.xml sek-20251231_g1.jpg http://xbrl.sec.gov/cyd/2025 http://xbrl.sec.gov/dei/2025 http://xbrl.sec.gov/ecd/2025 https://xbrl.ifrs.org/taxonomy/2025-03-27/ifrs-full true true