<?xml version='1.0' encoding='utf-8'?>
<FilingSummary>
  <Version>3.24.1</Version>
  <ProcessingTime/>
  <ReportFormat>html</ReportFormat>
  <ContextCount>2448</ContextCount>
  <ElementCount>1234</ElementCount>
  <EntityCount>1</EntityCount>
  <FootnotesReported>true</FootnotesReported>
  <SegmentCount>481</SegmentCount>
  <ScenarioCount>0</ScenarioCount>
  <TuplesReported>false</TuplesReported>
  <UnitCount>16</UnitCount>
  <MyReports>
    <Report instance="cs-20231231.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R1.htm</HtmlFileName>
      <LongName>00000 - Document - Document and Entity Information</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.credit-suisse.com/role/DocumentAndEntityInformation</Role>
      <ShortName>Document and Entity Information</ShortName>
      <MenuCategory>Cover</MenuCategory>
      <Position>1</Position>
    </Report>
    <Report instance="cs-20231231.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R2.htm</HtmlFileName>
      <LongName>00100 - Statement - Consolidated statements of operations</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.credit-suisse.com/role/StatementOfIncome</Role>
      <ShortName>Consolidated statements of operations</ShortName>
      <MenuCategory>Statements</MenuCategory>
      <Position>2</Position>
    </Report>
    <Report instance="cs-20231231.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R3.htm</HtmlFileName>
      <LongName>00150 - Statement - Consolidated statements of comprehensive income</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.credit-suisse.com/role/StatementOfComprehensiveIncome</Role>
      <ShortName>Consolidated statements of comprehensive income</ShortName>
      <MenuCategory>Statements</MenuCategory>
      <Position>3</Position>
    </Report>
    <Report instance="cs-20231231.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R4.htm</HtmlFileName>
      <LongName>00200 - Statement - Consolidated balance sheets</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.credit-suisse.com/role/BalanceSheet</Role>
      <ShortName>Consolidated balance sheets</ShortName>
      <MenuCategory>Statements</MenuCategory>
      <Position>4</Position>
    </Report>
    <Report instance="cs-20231231.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R5.htm</HtmlFileName>
      <LongName>00250 - Statement - Consolidated balance sheets (Parenthetical)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.credit-suisse.com/role/BalanceSheetParenthetical</Role>
      <ShortName>Consolidated balance sheets (Parenthetical)</ShortName>
      <MenuCategory>Statements</MenuCategory>
      <Position>5</Position>
    </Report>
    <Report instance="cs-20231231.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R6.htm</HtmlFileName>
      <LongName>00300 - Statement - Consolidated statements of changes in equity</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.credit-suisse.com/role/StatementOfStockholdersEquity</Role>
      <ShortName>Consolidated statements of changes in equity</ShortName>
      <MenuCategory>Statements</MenuCategory>
      <Position>6</Position>
    </Report>
    <Report instance="cs-20231231.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R7.htm</HtmlFileName>
      <LongName>00500 - Statement - Consolidated statements of cash flows</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.credit-suisse.com/role/CashFlows</Role>
      <ShortName>Consolidated statements of cash flows</ShortName>
      <MenuCategory>Statements</MenuCategory>
      <Position>7</Position>
    </Report>
    <Report instance="cs-20231231.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R8.htm</HtmlFileName>
      <LongName>10100 - Disclosure - Summary of significant accounting policies</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.credit-suisse.com/role/DisclosureSummaryOfSignificantAccountingPolicies</Role>
      <ShortName>Summary of significant accounting policies</ShortName>
      <MenuCategory>Notes</MenuCategory>
      <Position>8</Position>
    </Report>
    <Report instance="cs-20231231.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R9.htm</HtmlFileName>
      <LongName>10200 - Disclosure - Recently issued accounting standards</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.credit-suisse.com/role/DisclosureRecentlyIssuedAccountingStandards</Role>
      <ShortName>Recently issued accounting standards</ShortName>
      <MenuCategory>Notes</MenuCategory>
      <Position>9</Position>
    </Report>
    <Report instance="cs-20231231.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R10.htm</HtmlFileName>
      <LongName>10300 - Disclosure - Business developments</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.credit-suisse.com/role/DisclosureBusinessDevelopments</Role>
      <ShortName>Business developments</ShortName>
      <MenuCategory>Notes</MenuCategory>
      <Position>10</Position>
    </Report>
    <Report instance="cs-20231231.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R11.htm</HtmlFileName>
      <LongName>10400 - Disclosure - Segment information</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.credit-suisse.com/role/DisclosureSegmentInformation</Role>
      <ShortName>Segment information</ShortName>
      <MenuCategory>Notes</MenuCategory>
      <Position>11</Position>
    </Report>
    <Report instance="cs-20231231.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R12.htm</HtmlFileName>
      <LongName>10500 - Disclosure - Net interest income</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.credit-suisse.com/role/DisclosureNetInterestIncome</Role>
      <ShortName>Net interest income</ShortName>
      <MenuCategory>Notes</MenuCategory>
      <Position>12</Position>
    </Report>
    <Report instance="cs-20231231.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R13.htm</HtmlFileName>
      <LongName>10600 - Disclosure - Commissions and fees</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.credit-suisse.com/role/DisclosureCommissionsAndFees</Role>
      <ShortName>Commissions and fees</ShortName>
      <MenuCategory>Notes</MenuCategory>
      <Position>13</Position>
    </Report>
    <Report instance="cs-20231231.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R14.htm</HtmlFileName>
      <LongName>10700 - Disclosure - Trading revenues</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.credit-suisse.com/role/DisclosureTradingRevenues</Role>
      <ShortName>Trading revenues</ShortName>
      <MenuCategory>Notes</MenuCategory>
      <Position>14</Position>
    </Report>
    <Report instance="cs-20231231.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R15.htm</HtmlFileName>
      <LongName>10800 - Disclosure - Other revenues</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.credit-suisse.com/role/DisclosureOtherRevenues</Role>
      <ShortName>Other revenues</ShortName>
      <MenuCategory>Notes</MenuCategory>
      <Position>15</Position>
    </Report>
    <Report instance="cs-20231231.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R16.htm</HtmlFileName>
      <LongName>10900 - Disclosure - Provision for credit losses</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.credit-suisse.com/role/DisclosureProvisionForCreditLosses</Role>
      <ShortName>Provision for credit losses</ShortName>
      <MenuCategory>Notes</MenuCategory>
      <Position>16</Position>
    </Report>
    <Report instance="cs-20231231.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R17.htm</HtmlFileName>
      <LongName>11000 - Disclosure - Compensation and benefits</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.credit-suisse.com/role/DisclosureCompensationAndBenefits</Role>
      <ShortName>Compensation and benefits</ShortName>
      <MenuCategory>Notes</MenuCategory>
      <Position>17</Position>
    </Report>
    <Report instance="cs-20231231.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R18.htm</HtmlFileName>
      <LongName>11100 - Disclosure - General and administrative expenses</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.credit-suisse.com/role/DisclosureGeneralAndAdministrativeExpenses</Role>
      <ShortName>General and administrative expenses</ShortName>
      <MenuCategory>Notes</MenuCategory>
      <Position>18</Position>
    </Report>
    <Report instance="cs-20231231.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R19.htm</HtmlFileName>
      <LongName>11200 - Disclosure - Restructuring expenses</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.credit-suisse.com/role/DisclosureRestructuringExpenses</Role>
      <ShortName>Restructuring expenses</ShortName>
      <MenuCategory>Notes</MenuCategory>
      <Position>19</Position>
    </Report>
    <Report instance="cs-20231231.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R20.htm</HtmlFileName>
      <LongName>11400 - Disclosure - Revenue from contracts with customers</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.credit-suisse.com/role/DisclosureRevenueFromContractsWithCustomers</Role>
      <ShortName>Revenue from contracts with customers</ShortName>
      <MenuCategory>Notes</MenuCategory>
      <Position>20</Position>
    </Report>
    <Report instance="cs-20231231.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R21.htm</HtmlFileName>
      <LongName>11500 - Disclosure - Securities borrowed, lent and subject to repurchase agreements</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.credit-suisse.com/role/DisclosureSecuritiesBorrowedLentAndSubjectToRepurchaseAgreements</Role>
      <ShortName>Securities borrowed, lent and subject to repurchase agreements</ShortName>
      <MenuCategory>Notes</MenuCategory>
      <Position>21</Position>
    </Report>
    <Report instance="cs-20231231.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R22.htm</HtmlFileName>
      <LongName>11700 - Disclosure - Investment securities</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.credit-suisse.com/role/DisclosureInvestmentSecurities</Role>
      <ShortName>Investment securities</ShortName>
      <MenuCategory>Notes</MenuCategory>
      <Position>22</Position>
    </Report>
    <Report instance="cs-20231231.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R23.htm</HtmlFileName>
      <LongName>11800 - Disclosure - Other investments</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.credit-suisse.com/role/DisclosureOtherInvestments</Role>
      <ShortName>Other investments</ShortName>
      <MenuCategory>Notes</MenuCategory>
      <Position>23</Position>
    </Report>
    <Report instance="cs-20231231.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R24.htm</HtmlFileName>
      <LongName>11900 - Disclosure - Loans, allowance for loan losses and credit quality</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.credit-suisse.com/role/DisclosureLoansAllowanceForLoanLossesAndCreditQuality</Role>
      <ShortName>Loans, allowance for loan losses and credit quality</ShortName>
      <MenuCategory>Notes</MenuCategory>
      <Position>24</Position>
    </Report>
    <Report instance="cs-20231231.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R25.htm</HtmlFileName>
      <LongName>12000 - Disclosure - CECL - Financial instruments measured at amortized cost and credit losses</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.credit-suisse.com/role/DisclosureCECL</Role>
      <ShortName>CECL - Financial instruments measured at amortized cost and credit losses</ShortName>
      <MenuCategory>Notes</MenuCategory>
      <Position>25</Position>
    </Report>
    <Report instance="cs-20231231.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R26.htm</HtmlFileName>
      <LongName>12100 - Disclosure - Goodwill</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.credit-suisse.com/role/DisclosureGoodwillAndOtherIntangibleAssets</Role>
      <ShortName>Goodwill</ShortName>
      <MenuCategory>Notes</MenuCategory>
      <Position>26</Position>
    </Report>
    <Report instance="cs-20231231.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R27.htm</HtmlFileName>
      <LongName>12200 - Disclosure - Other intangible assets</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.credit-suisse.com/role/DisclosureOtherIntangibleAssets</Role>
      <ShortName>Other intangible assets</ShortName>
      <MenuCategory>Notes</MenuCategory>
      <Position>27</Position>
    </Report>
    <Report instance="cs-20231231.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R28.htm</HtmlFileName>
      <LongName>12300 - Disclosure - Other assets and other liabilities</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.credit-suisse.com/role/DisclosureOtherAssetsAndOtherLiabilities</Role>
      <ShortName>Other assets and other liabilities</ShortName>
      <MenuCategory>Notes</MenuCategory>
      <Position>28</Position>
    </Report>
    <Report instance="cs-20231231.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R29.htm</HtmlFileName>
      <LongName>12400 - Disclosure - Leases</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.credit-suisse.com/role/DisclosureLeases</Role>
      <ShortName>Leases</ShortName>
      <MenuCategory>Notes</MenuCategory>
      <Position>29</Position>
    </Report>
    <Report instance="cs-20231231.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R30.htm</HtmlFileName>
      <LongName>12500 - Disclosure - Deposits</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.credit-suisse.com/role/DisclosureDeposits</Role>
      <ShortName>Deposits</ShortName>
      <MenuCategory>Notes</MenuCategory>
      <Position>30</Position>
    </Report>
    <Report instance="cs-20231231.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R31.htm</HtmlFileName>
      <LongName>12600 - Disclosure - Long-term debt</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.credit-suisse.com/role/DisclosureLongTermDebt</Role>
      <ShortName>Long-term debt</ShortName>
      <MenuCategory>Notes</MenuCategory>
      <Position>31</Position>
    </Report>
    <Report instance="cs-20231231.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R32.htm</HtmlFileName>
      <LongName>12700 - Disclosure - Accumulated other comprehensive income</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.credit-suisse.com/role/DisclosureAccumulatedOtherComprehensiveIncome</Role>
      <ShortName>Accumulated other comprehensive income</ShortName>
      <MenuCategory>Notes</MenuCategory>
      <Position>32</Position>
    </Report>
    <Report instance="cs-20231231.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R33.htm</HtmlFileName>
      <LongName>12800 - Disclosure - Offsetting of financial assets and financial liabilities</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.credit-suisse.com/role/DisclosureOffsettingOfFinancialAssetsAndFinancialLiabilities</Role>
      <ShortName>Offsetting of financial assets and financial liabilities</ShortName>
      <MenuCategory>Notes</MenuCategory>
      <Position>33</Position>
    </Report>
    <Report instance="cs-20231231.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R34.htm</HtmlFileName>
      <LongName>12900 - Disclosure - Tax</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.credit-suisse.com/role/DisclosureTax</Role>
      <ShortName>Tax</ShortName>
      <MenuCategory>Notes</MenuCategory>
      <Position>34</Position>
    </Report>
    <Report instance="cs-20231231.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R35.htm</HtmlFileName>
      <LongName>13000 - Disclosure - Employee deferred compensation</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.credit-suisse.com/role/DisclosureEmployeeDeferredCompensation</Role>
      <ShortName>Employee deferred compensation</ShortName>
      <MenuCategory>Notes</MenuCategory>
      <Position>35</Position>
    </Report>
    <Report instance="cs-20231231.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R36.htm</HtmlFileName>
      <LongName>13100 - Disclosure - Related parties</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.credit-suisse.com/role/DisclosureRelatedParties</Role>
      <ShortName>Related parties</ShortName>
      <MenuCategory>Notes</MenuCategory>
      <Position>36</Position>
    </Report>
    <Report instance="cs-20231231.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R37.htm</HtmlFileName>
      <LongName>13200 - Disclosure - Pension and other post-retirement benefits</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.credit-suisse.com/role/DisclosurePensionAndOtherPostRetirementBenefits</Role>
      <ShortName>Pension and other post-retirement benefits</ShortName>
      <MenuCategory>Notes</MenuCategory>
      <Position>37</Position>
    </Report>
    <Report instance="cs-20231231.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R38.htm</HtmlFileName>
      <LongName>13300 - Disclosure - Derivatives and hedging activities</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.credit-suisse.com/role/DisclosureDerivativesAndHedgingActivities</Role>
      <ShortName>Derivatives and hedging activities</ShortName>
      <MenuCategory>Notes</MenuCategory>
      <Position>38</Position>
    </Report>
    <Report instance="cs-20231231.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R39.htm</HtmlFileName>
      <LongName>13400 - Disclosure - Guarantees and commitments</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.credit-suisse.com/role/DisclosureGuaranteesAndCommitments</Role>
      <ShortName>Guarantees and commitments</ShortName>
      <MenuCategory>Notes</MenuCategory>
      <Position>39</Position>
    </Report>
    <Report instance="cs-20231231.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R40.htm</HtmlFileName>
      <LongName>13500 - Disclosure - Transfers of financial assets and variable interest entities</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.credit-suisse.com/role/DisclosureTransfersOfFinancialAssetsAndVariableInterestEntities</Role>
      <ShortName>Transfers of financial assets and variable interest entities</ShortName>
      <MenuCategory>Notes</MenuCategory>
      <Position>40</Position>
    </Report>
    <Report instance="cs-20231231.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R41.htm</HtmlFileName>
      <LongName>13600 - Disclosure - Financial instruments</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.credit-suisse.com/role/DisclosureFinancialInstruments</Role>
      <ShortName>Financial instruments</ShortName>
      <MenuCategory>Notes</MenuCategory>
      <Position>41</Position>
    </Report>
    <Report instance="cs-20231231.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R42.htm</HtmlFileName>
      <LongName>13700 - Disclosure - Assets pledged and collateral</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.credit-suisse.com/role/DisclosureAssetsPledgedOrAssigned</Role>
      <ShortName>Assets pledged and collateral</ShortName>
      <MenuCategory>Notes</MenuCategory>
      <Position>42</Position>
    </Report>
    <Report instance="cs-20231231.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R43.htm</HtmlFileName>
      <LongName>13800 - Disclosure - Capital adequacy</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.credit-suisse.com/role/DisclosureCapitalAdequacy</Role>
      <ShortName>Capital adequacy</ShortName>
      <MenuCategory>Notes</MenuCategory>
      <Position>43</Position>
    </Report>
    <Report instance="cs-20231231.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R44.htm</HtmlFileName>
      <LongName>13900 - Disclosure - Assets under management</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.credit-suisse.com/role/DisclosureAssetsUnderManagement</Role>
      <ShortName>Assets under management</ShortName>
      <MenuCategory>Notes</MenuCategory>
      <Position>44</Position>
    </Report>
    <Report instance="cs-20231231.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R45.htm</HtmlFileName>
      <LongName>14000 - Disclosure - Litigation</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.credit-suisse.com/role/DisclosureLitigation</Role>
      <ShortName>Litigation</ShortName>
      <MenuCategory>Notes</MenuCategory>
      <Position>45</Position>
    </Report>
    <Report instance="cs-20231231.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R46.htm</HtmlFileName>
      <LongName>14100 - Disclosure - Significant subsidiaries and equity method investments</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.credit-suisse.com/role/DisclosureSignificantSubsidiariesAndEquityMethodInvestments</Role>
      <ShortName>Significant subsidiaries and equity method investments</ShortName>
      <MenuCategory>Notes</MenuCategory>
      <Position>46</Position>
    </Report>
    <Report instance="cs-20231231.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R47.htm</HtmlFileName>
      <LongName>14400 - Disclosure - Significant valuation and income recognition differences between US GAAP and Swiss GAAP banking law (true and fair view)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.credit-suisse.com/role/DisclosureSignificantValuationAndIncomeRecognitionDifferencesBetweenUSGAAPAndSwissGAAPBankingLaw</Role>
      <ShortName>Significant valuation and income recognition differences between US GAAP and Swiss GAAP banking law (true and fair view)</ShortName>
      <MenuCategory>Notes</MenuCategory>
      <Position>47</Position>
    </Report>
    <Report instance="cs-20231231.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R48.htm</HtmlFileName>
      <LongName>20100 - Disclosure - Summary of significant accounting policies (Policies)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.credit-suisse.com/role/DisclosureSummaryOfSignificantAccountingPoliciesPolicies</Role>
      <ShortName>Summary of significant accounting policies (Policies)</ShortName>
      <MenuCategory>Policies</MenuCategory>
      <Position>48</Position>
    </Report>
    <Report instance="cs-20231231.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R49.htm</HtmlFileName>
      <LongName>30400 - Disclosure - Segment information (Tables)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.credit-suisse.com/role/DisclosureSegmentInformationTables</Role>
      <ShortName>Segment information (Tables)</ShortName>
      <MenuCategory>Tables</MenuCategory>
      <ParentRole>http://www.credit-suisse.com/role/DisclosureSegmentInformation</ParentRole>
      <Position>49</Position>
    </Report>
    <Report instance="cs-20231231.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R50.htm</HtmlFileName>
      <LongName>30500 - Disclosure - Net interest income (Tables)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.credit-suisse.com/role/DisclosureNetInterestIncomeTables</Role>
      <ShortName>Net interest income (Tables)</ShortName>
      <MenuCategory>Tables</MenuCategory>
      <ParentRole>http://www.credit-suisse.com/role/DisclosureNetInterestIncome</ParentRole>
      <Position>50</Position>
    </Report>
    <Report instance="cs-20231231.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R51.htm</HtmlFileName>
      <LongName>30600 - Disclosure - Commissions and fees (Tables)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.credit-suisse.com/role/DisclosureCommissionsAndFeesTables</Role>
      <ShortName>Commissions and fees (Tables)</ShortName>
      <MenuCategory>Tables</MenuCategory>
      <ParentRole>http://www.credit-suisse.com/role/DisclosureCommissionsAndFees</ParentRole>
      <Position>51</Position>
    </Report>
    <Report instance="cs-20231231.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R52.htm</HtmlFileName>
      <LongName>30700 - Disclosure - Trading revenues (Tables)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.credit-suisse.com/role/DisclosureTradingRevenuesTables</Role>
      <ShortName>Trading revenues (Tables)</ShortName>
      <MenuCategory>Tables</MenuCategory>
      <ParentRole>http://www.credit-suisse.com/role/DisclosureTradingRevenues</ParentRole>
      <Position>52</Position>
    </Report>
    <Report instance="cs-20231231.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R53.htm</HtmlFileName>
      <LongName>30800 - Disclosure - Other revenues (Tables)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.credit-suisse.com/role/DisclosureOtherRevenuesTables</Role>
      <ShortName>Other revenues (Tables)</ShortName>
      <MenuCategory>Tables</MenuCategory>
      <ParentRole>http://www.credit-suisse.com/role/DisclosureOtherRevenues</ParentRole>
      <Position>53</Position>
    </Report>
    <Report instance="cs-20231231.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R54.htm</HtmlFileName>
      <LongName>30900 - Disclosure - Provision for credit losses (Tables)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.credit-suisse.com/role/DisclosureProvisionForCreditLossesTables</Role>
      <ShortName>Provision for credit losses (Tables)</ShortName>
      <MenuCategory>Tables</MenuCategory>
      <ParentRole>http://www.credit-suisse.com/role/DisclosureProvisionForCreditLosses</ParentRole>
      <Position>54</Position>
    </Report>
    <Report instance="cs-20231231.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R55.htm</HtmlFileName>
      <LongName>31000 - Disclosure - Compensation and benefits (Tables)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.credit-suisse.com/role/DisclosureCompensationAndBenefitsTables</Role>
      <ShortName>Compensation and benefits (Tables)</ShortName>
      <MenuCategory>Tables</MenuCategory>
      <ParentRole>http://www.credit-suisse.com/role/DisclosureCompensationAndBenefits</ParentRole>
      <Position>55</Position>
    </Report>
    <Report instance="cs-20231231.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R56.htm</HtmlFileName>
      <LongName>31100 - Disclosure - General and administrative expenses (Tables)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.credit-suisse.com/role/DisclosureGeneralAndAdministrativeExpensesTables</Role>
      <ShortName>General and administrative expenses (Tables)</ShortName>
      <MenuCategory>Tables</MenuCategory>
      <ParentRole>http://www.credit-suisse.com/role/DisclosureGeneralAndAdministrativeExpenses</ParentRole>
      <Position>56</Position>
    </Report>
    <Report instance="cs-20231231.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R57.htm</HtmlFileName>
      <LongName>31200 - Disclosure - Restructuring expenses (Tables)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.credit-suisse.com/role/DisclosureRestructuringExpensesTables</Role>
      <ShortName>Restructuring expenses (Tables)</ShortName>
      <MenuCategory>Tables</MenuCategory>
      <ParentRole>http://www.credit-suisse.com/role/DisclosureRestructuringExpenses</ParentRole>
      <Position>57</Position>
    </Report>
    <Report instance="cs-20231231.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R58.htm</HtmlFileName>
      <LongName>31400 - Disclosure - Revenue from contracts with customers (Tables)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.credit-suisse.com/role/DisclosureRevenueFromContractsWithCustomersTables</Role>
      <ShortName>Revenue from contracts with customers (Tables)</ShortName>
      <MenuCategory>Tables</MenuCategory>
      <ParentRole>http://www.credit-suisse.com/role/DisclosureRevenueFromContractsWithCustomers</ParentRole>
      <Position>58</Position>
    </Report>
    <Report instance="cs-20231231.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R59.htm</HtmlFileName>
      <LongName>31500 - Disclosure - Securities borrowed, lent and subject to repurchase agreements (Tables)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.credit-suisse.com/role/DisclosureSecuritiesBorrowedLentAndSubjectToRepurchaseAgreementsTables</Role>
      <ShortName>Securities borrowed, lent and subject to repurchase agreements (Tables)</ShortName>
      <MenuCategory>Tables</MenuCategory>
      <ParentRole>http://www.credit-suisse.com/role/DisclosureSecuritiesBorrowedLentAndSubjectToRepurchaseAgreements</ParentRole>
      <Position>59</Position>
    </Report>
    <Report instance="cs-20231231.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R60.htm</HtmlFileName>
      <LongName>31700 - Disclosure - Investment securities (Tables)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.credit-suisse.com/role/DisclosureInvestmentSecuritiesTables</Role>
      <ShortName>Investment securities (Tables)</ShortName>
      <MenuCategory>Tables</MenuCategory>
      <ParentRole>http://www.credit-suisse.com/role/DisclosureInvestmentSecurities</ParentRole>
      <Position>60</Position>
    </Report>
    <Report instance="cs-20231231.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R61.htm</HtmlFileName>
      <LongName>31800 - Disclosure - Other investments (Tables)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.credit-suisse.com/role/DisclosureOtherInvestmentsTables</Role>
      <ShortName>Other investments (Tables)</ShortName>
      <MenuCategory>Tables</MenuCategory>
      <ParentRole>http://www.credit-suisse.com/role/DisclosureOtherInvestments</ParentRole>
      <Position>61</Position>
    </Report>
    <Report instance="cs-20231231.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R62.htm</HtmlFileName>
      <LongName>31900 - Disclosure - Loans, allowance for loan losses and credit quality (Tables)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.credit-suisse.com/role/DisclosureLoansAllowanceForLoanLossesAndCreditQualityTables</Role>
      <ShortName>Loans, allowance for loan losses and credit quality (Tables)</ShortName>
      <MenuCategory>Tables</MenuCategory>
      <ParentRole>http://www.credit-suisse.com/role/DisclosureLoansAllowanceForLoanLossesAndCreditQuality</ParentRole>
      <Position>62</Position>
    </Report>
    <Report instance="cs-20231231.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R63.htm</HtmlFileName>
      <LongName>32000 - Disclosure - CECL - Financial instruments measured at amortized cost and credit losses (Tables)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.credit-suisse.com/role/DisclosureCECLTables</Role>
      <ShortName>CECL - Financial instruments measured at amortized cost and credit losses (Tables)</ShortName>
      <MenuCategory>Tables</MenuCategory>
      <ParentRole>http://www.credit-suisse.com/role/DisclosureCECL</ParentRole>
      <Position>63</Position>
    </Report>
    <Report instance="cs-20231231.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R64.htm</HtmlFileName>
      <LongName>32100 - Disclosure - Goodwill (Tables)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.credit-suisse.com/role/DisclosureGoodwillAndOtherIntangibleAssetsTables</Role>
      <ShortName>Goodwill (Tables)</ShortName>
      <MenuCategory>Tables</MenuCategory>
      <ParentRole>http://www.credit-suisse.com/role/DisclosureGoodwillAndOtherIntangibleAssets</ParentRole>
      <Position>64</Position>
    </Report>
    <Report instance="cs-20231231.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R65.htm</HtmlFileName>
      <LongName>32200 - Disclosure - Other intangible assets (Tables)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.credit-suisse.com/role/DisclosureOtherIntangibleAssetsTables</Role>
      <ShortName>Other intangible assets (Tables)</ShortName>
      <MenuCategory>Tables</MenuCategory>
      <ParentRole>http://www.credit-suisse.com/role/DisclosureOtherIntangibleAssets</ParentRole>
      <Position>65</Position>
    </Report>
    <Report instance="cs-20231231.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R66.htm</HtmlFileName>
      <LongName>32300 - Disclosure - Other assets and other liabilities (Tables)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.credit-suisse.com/role/DisclosureOtherAssetsAndOtherLiabilitiesTables</Role>
      <ShortName>Other assets and other liabilities (Tables)</ShortName>
      <MenuCategory>Tables</MenuCategory>
      <ParentRole>http://www.credit-suisse.com/role/DisclosureOtherAssetsAndOtherLiabilities</ParentRole>
      <Position>66</Position>
    </Report>
    <Report instance="cs-20231231.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R67.htm</HtmlFileName>
      <LongName>32400 - Disclosure - Leases (Tables)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.credit-suisse.com/role/DisclosureLeasesTables</Role>
      <ShortName>Leases (Tables)</ShortName>
      <MenuCategory>Tables</MenuCategory>
      <ParentRole>http://www.credit-suisse.com/role/DisclosureLeases</ParentRole>
      <Position>67</Position>
    </Report>
    <Report instance="cs-20231231.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R68.htm</HtmlFileName>
      <LongName>32500 - Disclosure - Deposits (Tables)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.credit-suisse.com/role/DisclosureDepositsTables</Role>
      <ShortName>Deposits (Tables)</ShortName>
      <MenuCategory>Tables</MenuCategory>
      <ParentRole>http://www.credit-suisse.com/role/DisclosureDeposits</ParentRole>
      <Position>68</Position>
    </Report>
    <Report instance="cs-20231231.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R69.htm</HtmlFileName>
      <LongName>32600 - Disclosure - Long-term debt (Tables)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.credit-suisse.com/role/DisclosureLongTermDebtTables</Role>
      <ShortName>Long-term debt (Tables)</ShortName>
      <MenuCategory>Tables</MenuCategory>
      <ParentRole>http://www.credit-suisse.com/role/DisclosureLongTermDebt</ParentRole>
      <Position>69</Position>
    </Report>
    <Report instance="cs-20231231.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R70.htm</HtmlFileName>
      <LongName>32700 - Disclosure - Accumulated other comprehensive income (Tables)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.credit-suisse.com/role/DisclosureAccumulatedOtherComprehensiveIncomeTables</Role>
      <ShortName>Accumulated other comprehensive income (Tables)</ShortName>
      <MenuCategory>Tables</MenuCategory>
      <ParentRole>http://www.credit-suisse.com/role/DisclosureAccumulatedOtherComprehensiveIncome</ParentRole>
      <Position>70</Position>
    </Report>
    <Report instance="cs-20231231.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R71.htm</HtmlFileName>
      <LongName>32800 - Disclosure - Offsetting of financial assets and financial liabilities (Tables)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.credit-suisse.com/role/DisclosureOffsettingOfFinancialAssetsAndFinancialLiabilitiesTables</Role>
      <ShortName>Offsetting of financial assets and financial liabilities (Tables)</ShortName>
      <MenuCategory>Tables</MenuCategory>
      <ParentRole>http://www.credit-suisse.com/role/DisclosureOffsettingOfFinancialAssetsAndFinancialLiabilities</ParentRole>
      <Position>71</Position>
    </Report>
    <Report instance="cs-20231231.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R72.htm</HtmlFileName>
      <LongName>32900 - Disclosure - Tax (Tables)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.credit-suisse.com/role/DisclosureTaxTables</Role>
      <ShortName>Tax (Tables)</ShortName>
      <MenuCategory>Tables</MenuCategory>
      <ParentRole>http://www.credit-suisse.com/role/DisclosureTax</ParentRole>
      <Position>72</Position>
    </Report>
    <Report instance="cs-20231231.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R73.htm</HtmlFileName>
      <LongName>33000 - Disclosure - Employee deferred compensation (Tables)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.credit-suisse.com/role/DisclosureEmployeeDeferredCompensationTables</Role>
      <ShortName>Employee deferred compensation (Tables)</ShortName>
      <MenuCategory>Tables</MenuCategory>
      <ParentRole>http://www.credit-suisse.com/role/DisclosureEmployeeDeferredCompensation</ParentRole>
      <Position>73</Position>
    </Report>
    <Report instance="cs-20231231.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R74.htm</HtmlFileName>
      <LongName>33100 - Disclosure - Related parties (Tables)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.credit-suisse.com/role/DisclosureRelatedPartiesTables</Role>
      <ShortName>Related parties (Tables)</ShortName>
      <MenuCategory>Tables</MenuCategory>
      <ParentRole>http://www.credit-suisse.com/role/DisclosureRelatedParties</ParentRole>
      <Position>74</Position>
    </Report>
    <Report instance="cs-20231231.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R75.htm</HtmlFileName>
      <LongName>33200 - Disclosure - Pension and other post-retirement benefits (Tables)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.credit-suisse.com/role/DisclosurePensionAndOtherPostRetirementBenefitsTables</Role>
      <ShortName>Pension and other post-retirement benefits (Tables)</ShortName>
      <MenuCategory>Tables</MenuCategory>
      <ParentRole>http://www.credit-suisse.com/role/DisclosurePensionAndOtherPostRetirementBenefits</ParentRole>
      <Position>75</Position>
    </Report>
    <Report instance="cs-20231231.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R76.htm</HtmlFileName>
      <LongName>33300 - Disclosure - Derivatives and hedging activities (Tables)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.credit-suisse.com/role/DisclosureDerivativesAndHedgingActivitiesTables</Role>
      <ShortName>Derivatives and hedging activities (Tables)</ShortName>
      <MenuCategory>Tables</MenuCategory>
      <ParentRole>http://www.credit-suisse.com/role/DisclosureDerivativesAndHedgingActivities</ParentRole>
      <Position>76</Position>
    </Report>
    <Report instance="cs-20231231.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R77.htm</HtmlFileName>
      <LongName>33400 - Disclosure - Guarantees and commitments (Tables)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.credit-suisse.com/role/DisclosureGuaranteesAndCommitmentsTables</Role>
      <ShortName>Guarantees and commitments (Tables)</ShortName>
      <MenuCategory>Tables</MenuCategory>
      <ParentRole>http://www.credit-suisse.com/role/DisclosureGuaranteesAndCommitments</ParentRole>
      <Position>77</Position>
    </Report>
    <Report instance="cs-20231231.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R78.htm</HtmlFileName>
      <LongName>33500 - Disclosure - Transfers of financial assets and variable interest entities (Tables)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.credit-suisse.com/role/DisclosureTransfersOfFinancialAssetsAndVariableInterestEntitiesTables</Role>
      <ShortName>Transfers of financial assets and variable interest entities (Tables)</ShortName>
      <MenuCategory>Tables</MenuCategory>
      <ParentRole>http://www.credit-suisse.com/role/DisclosureTransfersOfFinancialAssetsAndVariableInterestEntities</ParentRole>
      <Position>78</Position>
    </Report>
    <Report instance="cs-20231231.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R79.htm</HtmlFileName>
      <LongName>33600 - Disclosure - Financial instruments (Tables)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.credit-suisse.com/role/DisclosureFinancialInstrumentsTables</Role>
      <ShortName>Financial instruments (Tables)</ShortName>
      <MenuCategory>Tables</MenuCategory>
      <ParentRole>http://www.credit-suisse.com/role/DisclosureFinancialInstruments</ParentRole>
      <Position>79</Position>
    </Report>
    <Report instance="cs-20231231.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R80.htm</HtmlFileName>
      <LongName>33700 - Disclosure - Assets pledged and collateral (Tables)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.credit-suisse.com/role/DisclosureAssetsPledgedOrAssignedTables</Role>
      <ShortName>Assets pledged and collateral (Tables)</ShortName>
      <MenuCategory>Tables</MenuCategory>
      <ParentRole>http://www.credit-suisse.com/role/DisclosureAssetsPledgedOrAssigned</ParentRole>
      <Position>80</Position>
    </Report>
    <Report instance="cs-20231231.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R81.htm</HtmlFileName>
      <LongName>33800 - Disclosure - Capital adequacy (Tables)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.credit-suisse.com/role/DisclosureCapitalAdequacyTables</Role>
      <ShortName>Capital adequacy (Tables)</ShortName>
      <MenuCategory>Tables</MenuCategory>
      <ParentRole>http://www.credit-suisse.com/role/DisclosureCapitalAdequacy</ParentRole>
      <Position>81</Position>
    </Report>
    <Report instance="cs-20231231.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R82.htm</HtmlFileName>
      <LongName>33900 - Disclosure - Assets under management (Tables)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.credit-suisse.com/role/DisclosureAssetsUnderManagementTables</Role>
      <ShortName>Assets under management (Tables)</ShortName>
      <MenuCategory>Tables</MenuCategory>
      <ParentRole>http://www.credit-suisse.com/role/DisclosureAssetsUnderManagement</ParentRole>
      <Position>82</Position>
    </Report>
    <Report instance="cs-20231231.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R83.htm</HtmlFileName>
      <LongName>34000 - Disclosure - Litigation (Tables)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.credit-suisse.com/role/DisclosureLitigationTables</Role>
      <ShortName>Litigation (Tables)</ShortName>
      <MenuCategory>Tables</MenuCategory>
      <ParentRole>http://www.credit-suisse.com/role/DisclosureLitigation</ParentRole>
      <Position>83</Position>
    </Report>
    <Report instance="cs-20231231.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R84.htm</HtmlFileName>
      <LongName>34100 - Disclosure - Significant subsidiaries and equity method investments (Tables)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.credit-suisse.com/role/DisclosureSignificantSubsidiariesAndEquityMethodInvestmentsTables</Role>
      <ShortName>Significant subsidiaries and equity method investments (Tables)</ShortName>
      <MenuCategory>Tables</MenuCategory>
      <ParentRole>http://www.credit-suisse.com/role/DisclosureSignificantSubsidiariesAndEquityMethodInvestments</ParentRole>
      <Position>84</Position>
    </Report>
    <Report instance="cs-20231231.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R85.htm</HtmlFileName>
      <LongName>40100 - Disclosure - Summary of significant accounting policies (Details)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.credit-suisse.com/role/DisclosureSummaryOfSignificantAccountingPoliciesDetails1</Role>
      <ShortName>Summary of significant accounting policies (Details)</ShortName>
      <MenuCategory>Details</MenuCategory>
      <ParentRole>http://www.credit-suisse.com/role/DisclosureSummaryOfSignificantAccountingPoliciesPolicies</ParentRole>
      <Position>85</Position>
    </Report>
    <Report instance="cs-20231231.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R86.htm</HtmlFileName>
      <LongName>40101 - Disclosure - Summary of significant accounting policies - Useful lives (Details 2)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.credit-suisse.com/role/DisclosureSummaryOfSignificantAccountingPoliciesDetails2</Role>
      <ShortName>Summary of significant accounting policies - Useful lives (Details 2)</ShortName>
      <MenuCategory>Details</MenuCategory>
      <Position>86</Position>
    </Report>
    <Report instance="cs-20231231.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R87.htm</HtmlFileName>
      <LongName>40300 - Disclosure - Business developments (Details)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.credit-suisse.com/role/DisclosureBusinessDevelopmentsDetails</Role>
      <ShortName>Business developments (Details)</ShortName>
      <MenuCategory>Details</MenuCategory>
      <ParentRole>http://www.credit-suisse.com/role/DisclosureBusinessDevelopments</ParentRole>
      <Position>87</Position>
    </Report>
    <Report instance="cs-20231231.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R88.htm</HtmlFileName>
      <LongName>40303 - Disclosure - Business developments - Subsequent events (Details 4)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.credit-suisse.com/role/DisclosureBusinessDevelopmentsDetails4</Role>
      <ShortName>Business developments - Subsequent events (Details 4)</ShortName>
      <MenuCategory>Details</MenuCategory>
      <Position>88</Position>
    </Report>
    <Report instance="cs-20231231.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R89.htm</HtmlFileName>
      <LongName>40304 - Disclosure - Business developments - Business developments (Details 5)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.credit-suisse.com/role/DisclosureBusinessDevelopmentsDetails5</Role>
      <ShortName>Business developments - Business developments (Details 5)</ShortName>
      <MenuCategory>Details</MenuCategory>
      <Position>89</Position>
    </Report>
    <Report instance="cs-20231231.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R90.htm</HtmlFileName>
      <LongName>40400 - Disclosure - Segment information - Income statement related (Details)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.credit-suisse.com/role/DisclosureSegmentInformationDetails</Role>
      <ShortName>Segment information - Income statement related (Details)</ShortName>
      <MenuCategory>Details</MenuCategory>
      <Position>90</Position>
    </Report>
    <Report instance="cs-20231231.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R91.htm</HtmlFileName>
      <LongName>40401 - Disclosure - Segment information - Balance sheet related (Details 2)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.credit-suisse.com/role/DisclosureSegmentInformationDetails2</Role>
      <ShortName>Segment information - Balance sheet related (Details 2)</ShortName>
      <MenuCategory>Details</MenuCategory>
      <Position>91</Position>
    </Report>
    <Report instance="cs-20231231.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R92.htm</HtmlFileName>
      <LongName>40500 - Disclosure - Net interest income (Details)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.credit-suisse.com/role/DisclosureNetInterestIncomeDetails</Role>
      <ShortName>Net interest income (Details)</ShortName>
      <MenuCategory>Details</MenuCategory>
      <ParentRole>http://www.credit-suisse.com/role/DisclosureNetInterestIncomeTables</ParentRole>
      <Position>92</Position>
    </Report>
    <Report instance="cs-20231231.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R93.htm</HtmlFileName>
      <LongName>40600 - Disclosure - Commissions and fees (Details)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.credit-suisse.com/role/DisclosureCommissionsAndFeesDetails</Role>
      <ShortName>Commissions and fees (Details)</ShortName>
      <MenuCategory>Details</MenuCategory>
      <ParentRole>http://www.credit-suisse.com/role/DisclosureCommissionsAndFeesTables</ParentRole>
      <Position>93</Position>
    </Report>
    <Report instance="cs-20231231.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R94.htm</HtmlFileName>
      <LongName>40700 - Disclosure - Trading revenues (Details)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.credit-suisse.com/role/DisclosureTradingRevenuesDetails</Role>
      <ShortName>Trading revenues (Details)</ShortName>
      <MenuCategory>Details</MenuCategory>
      <ParentRole>http://www.credit-suisse.com/role/DisclosureTradingRevenuesTables</ParentRole>
      <Position>94</Position>
    </Report>
    <Report instance="cs-20231231.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R95.htm</HtmlFileName>
      <LongName>40800 - Disclosure - Other revenues (Details)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.credit-suisse.com/role/DisclosureOtherRevenuesDetails</Role>
      <ShortName>Other revenues (Details)</ShortName>
      <MenuCategory>Details</MenuCategory>
      <ParentRole>http://www.credit-suisse.com/role/DisclosureOtherRevenuesTables</ParentRole>
      <Position>95</Position>
    </Report>
    <Report instance="cs-20231231.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R96.htm</HtmlFileName>
      <LongName>40900 - Disclosure - Provision for credit losses (Details)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.credit-suisse.com/role/DisclosureProvisionForCreditLossesDetails</Role>
      <ShortName>Provision for credit losses (Details)</ShortName>
      <MenuCategory>Details</MenuCategory>
      <ParentRole>http://www.credit-suisse.com/role/DisclosureProvisionForCreditLossesTables</ParentRole>
      <Position>96</Position>
    </Report>
    <Report instance="cs-20231231.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R97.htm</HtmlFileName>
      <LongName>41000 - Disclosure - Compensation and benefits (Details)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.credit-suisse.com/role/DisclosureCompensationAndBenefitsDetails</Role>
      <ShortName>Compensation and benefits (Details)</ShortName>
      <MenuCategory>Details</MenuCategory>
      <ParentRole>http://www.credit-suisse.com/role/DisclosureCompensationAndBenefitsTables</ParentRole>
      <Position>97</Position>
    </Report>
    <Report instance="cs-20231231.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R98.htm</HtmlFileName>
      <LongName>41100 - Disclosure - General and administrative expenses (Details)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.credit-suisse.com/role/DisclosureGeneralAndAdministrativeExpensesDetails</Role>
      <ShortName>General and administrative expenses (Details)</ShortName>
      <MenuCategory>Details</MenuCategory>
      <ParentRole>http://www.credit-suisse.com/role/DisclosureGeneralAndAdministrativeExpensesTables</ParentRole>
      <Position>98</Position>
    </Report>
    <Report instance="cs-20231231.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R99.htm</HtmlFileName>
      <LongName>41200 - Disclosure - Restructuring expenses (Details)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.credit-suisse.com/role/DisclosureRestructuringExpensesDetails</Role>
      <ShortName>Restructuring expenses (Details)</ShortName>
      <MenuCategory>Details</MenuCategory>
      <ParentRole>http://www.credit-suisse.com/role/DisclosureRestructuringExpensesTables</ParentRole>
      <Position>99</Position>
    </Report>
    <Report instance="cs-20231231.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R100.htm</HtmlFileName>
      <LongName>41201 - Disclosure - Restructuring provision - Rollforward (Details 2)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.credit-suisse.com/role/DisclosureRestructuringExpensesDetails2</Role>
      <ShortName>Restructuring provision - Rollforward (Details 2)</ShortName>
      <MenuCategory>Details</MenuCategory>
      <Position>100</Position>
    </Report>
    <Report instance="cs-20231231.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R101.htm</HtmlFileName>
      <LongName>41400 - Disclosure - Revenue from contracts with customers (Details)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.credit-suisse.com/role/DisclosureRevenueFromContractsWithCustomersDetails</Role>
      <ShortName>Revenue from contracts with customers (Details)</ShortName>
      <MenuCategory>Details</MenuCategory>
      <ParentRole>http://www.credit-suisse.com/role/DisclosureRevenueFromContractsWithCustomersTables</ParentRole>
      <Position>101</Position>
    </Report>
    <Report instance="cs-20231231.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R102.htm</HtmlFileName>
      <LongName>41401 - Disclosure - Revenue from contracts with customers (Details 2)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.credit-suisse.com/role/DisclosureRevenueFromContractsWithCustomersDetails2</Role>
      <ShortName>Revenue from contracts with customers (Details 2)</ShortName>
      <MenuCategory>Details</MenuCategory>
      <ParentRole>http://www.credit-suisse.com/role/DisclosureRevenueFromContractsWithCustomersTables</ParentRole>
      <Position>102</Position>
    </Report>
    <Report instance="cs-20231231.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R103.htm</HtmlFileName>
      <LongName>41500 - Disclosure - Securities borrowed, lent and subject to repurchase agreements (Details)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.credit-suisse.com/role/DisclosureSecuritiesBorrowedLentAndSubjectToRepurchaseAgreementsDetails</Role>
      <ShortName>Securities borrowed, lent and subject to repurchase agreements (Details)</ShortName>
      <MenuCategory>Details</MenuCategory>
      <ParentRole>http://www.credit-suisse.com/role/DisclosureSecuritiesBorrowedLentAndSubjectToRepurchaseAgreementsTables</ParentRole>
      <Position>103</Position>
    </Report>
    <Report instance="cs-20231231.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R104.htm</HtmlFileName>
      <LongName>41600 - Disclosure - Trading assets and liabilities (Details)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.credit-suisse.com/role/DisclosureTradingAssetsAndLiabilitiesDetails</Role>
      <ShortName>Trading assets and liabilities (Details)</ShortName>
      <MenuCategory>Details</MenuCategory>
      <Position>104</Position>
    </Report>
    <Report instance="cs-20231231.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R105.htm</HtmlFileName>
      <LongName>41601 - Disclosure - Trading assets and liabilities - Cash collateral - netted (Details 2)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.credit-suisse.com/role/DisclosureTradingAssetsAndLiabilitiesDetails2</Role>
      <ShortName>Trading assets and liabilities - Cash collateral - netted (Details 2)</ShortName>
      <MenuCategory>Details</MenuCategory>
      <Position>105</Position>
    </Report>
    <Report instance="cs-20231231.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R106.htm</HtmlFileName>
      <LongName>41700 - Disclosure - Investment securities (Details)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.credit-suisse.com/role/DisclosureInvestmentSecuritiesDetails</Role>
      <ShortName>Investment securities (Details)</ShortName>
      <MenuCategory>Details</MenuCategory>
      <ParentRole>http://www.credit-suisse.com/role/DisclosureInvestmentSecuritiesTables</ParentRole>
      <Position>106</Position>
    </Report>
    <Report instance="cs-20231231.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R107.htm</HtmlFileName>
      <LongName>41701 - Disclosure - Investment securities by type (Details 2)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.credit-suisse.com/role/DisclosureInvestmentSecuritiesDetails2</Role>
      <ShortName>Investment securities by type (Details 2)</ShortName>
      <MenuCategory>Details</MenuCategory>
      <Position>107</Position>
    </Report>
    <Report instance="cs-20231231.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R108.htm</HtmlFileName>
      <LongName>41702 - Disclosure - Investment securities - Unrealized losses/fair value (Details 3)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.credit-suisse.com/role/DisclosureInvestmentSecuritiesDetails3</Role>
      <ShortName>Investment securities - Unrealized losses/fair value (Details 3)</ShortName>
      <MenuCategory>Details</MenuCategory>
      <Position>108</Position>
    </Report>
    <Report instance="cs-20231231.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R109.htm</HtmlFileName>
      <LongName>41703 - Disclosure - Investment securities - Proceeds/realized gains/losses (Details 4)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.credit-suisse.com/role/DisclosureInvestmentSecuritiesDetails4</Role>
      <ShortName>Investment securities - Proceeds/realized gains/losses (Details 4)</ShortName>
      <MenuCategory>Details</MenuCategory>
      <Position>109</Position>
    </Report>
    <Report instance="cs-20231231.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R110.htm</HtmlFileName>
      <LongName>41704 - Disclosure - Investment securities - Maturities of amortized costs/FV/Avg yield (Details 5)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.credit-suisse.com/role/DisclosureInvestmentSecuritiesDetails5</Role>
      <ShortName>Investment securities - Maturities of amortized costs/FV/Avg yield (Details 5)</ShortName>
      <MenuCategory>Details</MenuCategory>
      <Position>110</Position>
    </Report>
    <Report instance="cs-20231231.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R111.htm</HtmlFileName>
      <LongName>41705 - Disclosure - Investment securities - Maturities of amortized costs/FV/Avg yield (Details 6)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.credit-suisse.com/role/DisclosureInvestmentSecuritiesDetails8</Role>
      <ShortName>Investment securities - Maturities of amortized costs/FV/Avg yield (Details 6)</ShortName>
      <MenuCategory>Details</MenuCategory>
      <Position>111</Position>
    </Report>
    <Report instance="cs-20231231.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R112.htm</HtmlFileName>
      <LongName>41706 - Disclosure - Investment securities - Allowance for credit loss (Details 7)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.credit-suisse.com/role/DisclosureInvestmentSecuritiesDetails6</Role>
      <ShortName>Investment securities - Allowance for credit loss (Details 7)</ShortName>
      <MenuCategory>Details</MenuCategory>
      <Position>112</Position>
    </Report>
    <Report instance="cs-20231231.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R113.htm</HtmlFileName>
      <LongName>41800 - Disclosure - Other investments (Details)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.credit-suisse.com/role/DisclosureOtherInvestmentsDetails</Role>
      <ShortName>Other investments (Details)</ShortName>
      <MenuCategory>Details</MenuCategory>
      <ParentRole>http://www.credit-suisse.com/role/DisclosureOtherInvestmentsTables</ParentRole>
      <Position>113</Position>
    </Report>
    <Report instance="cs-20231231.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R114.htm</HtmlFileName>
      <LongName>41801 - Disclosure - Other investments (Details 2)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.credit-suisse.com/role/DisclosureOtherInvestmentsDetails2</Role>
      <ShortName>Other investments (Details 2)</ShortName>
      <MenuCategory>Details</MenuCategory>
      <ParentRole>http://www.credit-suisse.com/role/DisclosureOtherInvestmentsTables</ParentRole>
      <Position>114</Position>
    </Report>
    <Report instance="cs-20231231.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R115.htm</HtmlFileName>
      <LongName>41900 - Disclosure - Loans, allowance for loan losses and credit quality (Details)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.credit-suisse.com/role/DisclosureLoansAllowanceForLoanLossesAndCreditQualityDetails</Role>
      <ShortName>Loans, allowance for loan losses and credit quality (Details)</ShortName>
      <MenuCategory>Details</MenuCategory>
      <ParentRole>http://www.credit-suisse.com/role/DisclosureLoansAllowanceForLoanLossesAndCreditQualityTables</ParentRole>
      <Position>115</Position>
    </Report>
    <Report instance="cs-20231231.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R116.htm</HtmlFileName>
      <LongName>42000 - Disclosure - CECL - Financial instruments measured at amortized cost and credit losses (Details)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.credit-suisse.com/role/DisclosureCECLDetails</Role>
      <ShortName>CECL - Financial instruments measured at amortized cost and credit losses (Details)</ShortName>
      <MenuCategory>Details</MenuCategory>
      <ParentRole>http://www.credit-suisse.com/role/DisclosureCECLTables</ParentRole>
      <Position>116</Position>
    </Report>
    <Report instance="cs-20231231.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R117.htm</HtmlFileName>
      <LongName>42001 - Disclosure - CECL - Financial instruments measured at amortized cost and credit losses (Details 1)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.credit-suisse.com/role/DisclosureCECLDetailsParenthetical</Role>
      <ShortName>CECL - Financial instruments measured at amortized cost and credit losses (Details 1)</ShortName>
      <MenuCategory>Details</MenuCategory>
      <ParentRole>http://www.credit-suisse.com/role/DisclosureCECLTables</ParentRole>
      <Position>117</Position>
    </Report>
    <Report instance="cs-20231231.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R118.htm</HtmlFileName>
      <LongName>42002 - Disclosure - CECL (Details 2)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.credit-suisse.com/role/DisclosureCECLDetails2</Role>
      <ShortName>CECL (Details 2)</ShortName>
      <MenuCategory>Details</MenuCategory>
      <ParentRole>http://www.credit-suisse.com/role/DisclosureCECLTables</ParentRole>
      <Position>118</Position>
    </Report>
    <Report instance="cs-20231231.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R119.htm</HtmlFileName>
      <LongName>42003 - Disclosure - CECL (Details 3)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.credit-suisse.com/role/DisclosureCECLDetails3</Role>
      <ShortName>CECL (Details 3)</ShortName>
      <MenuCategory>Details</MenuCategory>
      <ParentRole>http://www.credit-suisse.com/role/DisclosureCECLTables</ParentRole>
      <Position>119</Position>
    </Report>
    <Report instance="cs-20231231.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R120.htm</HtmlFileName>
      <LongName>42004 - Disclosure - CECL (Details 4)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.credit-suisse.com/role/DisclosureCECLDetails13</Role>
      <ShortName>CECL (Details 4)</ShortName>
      <MenuCategory>Details</MenuCategory>
      <ParentRole>http://www.credit-suisse.com/role/DisclosureCECLTables</ParentRole>
      <Position>120</Position>
    </Report>
    <Report instance="cs-20231231.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R121.htm</HtmlFileName>
      <LongName>42005 - Disclosure - CECL (Details 5)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.credit-suisse.com/role/DisclosureCECLDetails4</Role>
      <ShortName>CECL (Details 5)</ShortName>
      <MenuCategory>Details</MenuCategory>
      <ParentRole>http://www.credit-suisse.com/role/DisclosureCECLTables</ParentRole>
      <Position>121</Position>
    </Report>
    <Report instance="cs-20231231.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R122.htm</HtmlFileName>
      <LongName>42006 - Disclosure - CECL (Details 6)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.credit-suisse.com/role/DisclosureCECLDetails5</Role>
      <ShortName>CECL (Details 6)</ShortName>
      <MenuCategory>Details</MenuCategory>
      <ParentRole>http://www.credit-suisse.com/role/DisclosureCECLTables</ParentRole>
      <Position>122</Position>
    </Report>
    <Report instance="cs-20231231.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R123.htm</HtmlFileName>
      <LongName>42007 - Disclosure - CECL (Details 7)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.credit-suisse.com/role/DisclosureCECLDetails6</Role>
      <ShortName>CECL (Details 7)</ShortName>
      <MenuCategory>Details</MenuCategory>
      <ParentRole>http://www.credit-suisse.com/role/DisclosureCECLTables</ParentRole>
      <Position>123</Position>
    </Report>
    <Report instance="cs-20231231.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R124.htm</HtmlFileName>
      <LongName>42008 - Disclosure - CECL (Details 8)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.credit-suisse.com/role/DisclosureCECLDetails7</Role>
      <ShortName>CECL (Details 8)</ShortName>
      <MenuCategory>Details</MenuCategory>
      <ParentRole>http://www.credit-suisse.com/role/DisclosureCECLTables</ParentRole>
      <Position>124</Position>
    </Report>
    <Report instance="cs-20231231.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R125.htm</HtmlFileName>
      <LongName>42009 - Disclosure - CECL (Details 9)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.credit-suisse.com/role/DisclosureCECLDetails8</Role>
      <ShortName>CECL (Details 9)</ShortName>
      <MenuCategory>Details</MenuCategory>
      <ParentRole>http://www.credit-suisse.com/role/DisclosureCECLTables</ParentRole>
      <Position>125</Position>
    </Report>
    <Report instance="cs-20231231.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R126.htm</HtmlFileName>
      <LongName>42010 - Disclosure - CECL (Details 10)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.credit-suisse.com/role/DisclosureCECLDetails9</Role>
      <ShortName>CECL (Details 10)</ShortName>
      <MenuCategory>Details</MenuCategory>
      <ParentRole>http://www.credit-suisse.com/role/DisclosureCECLTables</ParentRole>
      <Position>126</Position>
    </Report>
    <Report instance="cs-20231231.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R127.htm</HtmlFileName>
      <LongName>42012 - Disclosure - CECL (Details 12)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.credit-suisse.com/role/DisclosureCECLDetails11</Role>
      <ShortName>CECL (Details 12)</ShortName>
      <MenuCategory>Details</MenuCategory>
      <ParentRole>http://www.credit-suisse.com/role/DisclosureCECLTables</ParentRole>
      <Position>127</Position>
    </Report>
    <Report instance="cs-20231231.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R128.htm</HtmlFileName>
      <LongName>42014 - Disclosure - CECL (Details 14)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.credit-suisse.com/role/DisclosureCECLDetails14</Role>
      <ShortName>CECL (Details 14)</ShortName>
      <MenuCategory>Details</MenuCategory>
      <ParentRole>http://www.credit-suisse.com/role/DisclosureCECLTables</ParentRole>
      <Position>128</Position>
    </Report>
    <Report instance="cs-20231231.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R129.htm</HtmlFileName>
      <LongName>42015 - Disclosure - CECL (Details 15)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.credit-suisse.com/role/DisclosureCECLDetails15</Role>
      <ShortName>CECL (Details 15)</ShortName>
      <MenuCategory>Details</MenuCategory>
      <ParentRole>http://www.credit-suisse.com/role/DisclosureCECLTables</ParentRole>
      <Position>129</Position>
    </Report>
    <Report instance="cs-20231231.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R130.htm</HtmlFileName>
      <LongName>42016 - Disclosure - CECL (Details 16)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.credit-suisse.com/role/DisclosureCECLDetails16</Role>
      <ShortName>CECL (Details 16)</ShortName>
      <MenuCategory>Details</MenuCategory>
      <ParentRole>http://www.credit-suisse.com/role/DisclosureCECLTables</ParentRole>
      <Position>130</Position>
    </Report>
    <Report instance="cs-20231231.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R131.htm</HtmlFileName>
      <LongName>42100 - Disclosure - Goodwill (Details)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.credit-suisse.com/role/DisclosureGoodwillAndOtherIntangibleAssetsDetails</Role>
      <ShortName>Goodwill (Details)</ShortName>
      <MenuCategory>Details</MenuCategory>
      <ParentRole>http://www.credit-suisse.com/role/DisclosureGoodwillAndOtherIntangibleAssetsTables</ParentRole>
      <Position>131</Position>
    </Report>
    <Report instance="cs-20231231.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R132.htm</HtmlFileName>
      <LongName>42200 - Disclosure - Other intangible assets (Details 1)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.credit-suisse.com/role/DisclosureGoodwillAndOtherIntangibleAssetsDetails2</Role>
      <ShortName>Other intangible assets (Details 1)</ShortName>
      <MenuCategory>Details</MenuCategory>
      <ParentRole>http://www.credit-suisse.com/role/DisclosureOtherIntangibleAssetsTables</ParentRole>
      <Position>132</Position>
    </Report>
    <Report instance="cs-20231231.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R133.htm</HtmlFileName>
      <LongName>42300 - Disclosure - Other assets and other liabilities (Details)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.credit-suisse.com/role/DisclosureOtherAssetsAndOtherLiabilitiesDetails</Role>
      <ShortName>Other assets and other liabilities (Details)</ShortName>
      <MenuCategory>Details</MenuCategory>
      <ParentRole>http://www.credit-suisse.com/role/DisclosureOtherAssetsAndOtherLiabilitiesTables</ParentRole>
      <Position>133</Position>
    </Report>
    <Report instance="cs-20231231.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R134.htm</HtmlFileName>
      <LongName>42301 - Disclosure - Other assets and other liabilities (Details 2)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.credit-suisse.com/role/DisclosureOtherAssetsAndOtherLiabilitiesDetails1</Role>
      <ShortName>Other assets and other liabilities (Details 2)</ShortName>
      <MenuCategory>Details</MenuCategory>
      <ParentRole>http://www.credit-suisse.com/role/DisclosureOtherAssetsAndOtherLiabilitiesTables</ParentRole>
      <Position>134</Position>
    </Report>
    <Report instance="cs-20231231.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R135.htm</HtmlFileName>
      <LongName>42400 - Disclosure - Leases (Details)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.credit-suisse.com/role/DisclosureLeasesDetails</Role>
      <ShortName>Leases (Details)</ShortName>
      <MenuCategory>Details</MenuCategory>
      <ParentRole>http://www.credit-suisse.com/role/DisclosureLeasesTables</ParentRole>
      <Position>135</Position>
    </Report>
    <Report instance="cs-20231231.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R136.htm</HtmlFileName>
      <LongName>42401 - Disclosure - Leases (Details 2)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.credit-suisse.com/role/DisclosureLeasesDetails1</Role>
      <ShortName>Leases (Details 2)</ShortName>
      <MenuCategory>Details</MenuCategory>
      <ParentRole>http://www.credit-suisse.com/role/DisclosureLeasesTables</ParentRole>
      <Position>136</Position>
    </Report>
    <Report instance="cs-20231231.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R137.htm</HtmlFileName>
      <LongName>42500 - Disclosure - Deposits (Details)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.credit-suisse.com/role/DisclosureDepositsDetails</Role>
      <ShortName>Deposits (Details)</ShortName>
      <MenuCategory>Details</MenuCategory>
      <ParentRole>http://www.credit-suisse.com/role/DisclosureDepositsTables</ParentRole>
      <Position>137</Position>
    </Report>
    <Report instance="cs-20231231.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R138.htm</HtmlFileName>
      <LongName>42600 - Disclosure - Long-term debt (Details)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.credit-suisse.com/role/DisclosureLongTermDebtDetails</Role>
      <ShortName>Long-term debt (Details)</ShortName>
      <MenuCategory>Details</MenuCategory>
      <ParentRole>http://www.credit-suisse.com/role/DisclosureLongTermDebtTables</ParentRole>
      <Position>138</Position>
    </Report>
    <Report instance="cs-20231231.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R139.htm</HtmlFileName>
      <LongName>42601 - Disclosure - Long-term debt - Maturities (Details 2)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.credit-suisse.com/role/DisclosureLongTermDebtDetails2</Role>
      <ShortName>Long-term debt - Maturities (Details 2)</ShortName>
      <MenuCategory>Details</MenuCategory>
      <Position>139</Position>
    </Report>
    <Report instance="cs-20231231.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R140.htm</HtmlFileName>
      <LongName>42700 - Disclosure - Accumulated other comprehensive income (Details)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.credit-suisse.com/role/DisclosureAccumulatedOtherComprehensiveIncomeDetails</Role>
      <ShortName>Accumulated other comprehensive income (Details)</ShortName>
      <MenuCategory>Details</MenuCategory>
      <ParentRole>http://www.credit-suisse.com/role/DisclosureAccumulatedOtherComprehensiveIncomeTables</ParentRole>
      <Position>140</Position>
    </Report>
    <Report instance="cs-20231231.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R141.htm</HtmlFileName>
      <LongName>42702 - Disclosure - AOCI - Significant reclassification adjustments (Details 3)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.credit-suisse.com/role/DisclosureAccumulatedOtherComprehensiveIncomeDetails3</Role>
      <ShortName>AOCI - Significant reclassification adjustments (Details 3)</ShortName>
      <MenuCategory>Details</MenuCategory>
      <Position>141</Position>
    </Report>
    <Report instance="cs-20231231.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R142.htm</HtmlFileName>
      <LongName>42800 - Disclosure - Offsetting of financial assets (Details)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.credit-suisse.com/role/DisclosureOffsettingOfFinancialAssetsAndFinancialLiabilitiesDetails</Role>
      <ShortName>Offsetting of financial assets (Details)</ShortName>
      <MenuCategory>Details</MenuCategory>
      <ParentRole>http://www.credit-suisse.com/role/DisclosureOffsettingOfFinancialAssetsAndFinancialLiabilitiesTables</ParentRole>
      <Position>142</Position>
    </Report>
    <Report instance="cs-20231231.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R143.htm</HtmlFileName>
      <LongName>42801 - Disclosure - Offsetting of financial liabilities (Details 2)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.credit-suisse.com/role/DisclosureOffsettingOfFinancialAssetsAndFinancialLiabilitiesDetails2</Role>
      <ShortName>Offsetting of financial liabilities (Details 2)</ShortName>
      <MenuCategory>Details</MenuCategory>
      <Position>143</Position>
    </Report>
    <Report instance="cs-20231231.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R144.htm</HtmlFileName>
      <LongName>42900 - Disclosure - Tax - Income statement related/reconciliation of tax rate (Details)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.credit-suisse.com/role/DisclosureTaxDetails</Role>
      <ShortName>Tax - Income statement related/reconciliation of tax rate (Details)</ShortName>
      <MenuCategory>Details</MenuCategory>
      <Position>144</Position>
    </Report>
    <Report instance="cs-20231231.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R145.htm</HtmlFileName>
      <LongName>42901 - Disclosure - Tax - Balance sheet related (Details 2)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.credit-suisse.com/role/DisclosureTaxDetails2</Role>
      <ShortName>Tax - Balance sheet related (Details 2)</ShortName>
      <MenuCategory>Details</MenuCategory>
      <Position>145</Position>
    </Report>
    <Report instance="cs-20231231.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R146.htm</HtmlFileName>
      <LongName>42903 - Disclosure - Tax - Net deferred tax assets/liabilities by type (Details 3)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.credit-suisse.com/role/DisclosureTaxDetails4</Role>
      <ShortName>Tax - Net deferred tax assets/liabilities by type (Details 3)</ShortName>
      <MenuCategory>Details</MenuCategory>
      <Position>146</Position>
    </Report>
    <Report instance="cs-20231231.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R147.htm</HtmlFileName>
      <LongName>43000 - Disclosure - Deferred compensation expense (Details)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.credit-suisse.com/role/DisclosureEmployeeDeferredCompensationDetails</Role>
      <ShortName>Deferred compensation expense (Details)</ShortName>
      <MenuCategory>Details</MenuCategory>
      <Position>147</Position>
    </Report>
    <Report instance="cs-20231231.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R148.htm</HtmlFileName>
      <LongName>43001 - Disclosure - Estimated unrecognized deferred compensation (Details 2)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.credit-suisse.com/role/DisclosureEmployeeDeferredCompensationDetails2</Role>
      <ShortName>Estimated unrecognized deferred compensation (Details 2)</ShortName>
      <MenuCategory>Details</MenuCategory>
      <Position>148</Position>
    </Report>
    <Report instance="cs-20231231.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R149.htm</HtmlFileName>
      <LongName>43002 - Disclosure - Share-based awards (Details 3)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.credit-suisse.com/role/DisclosureEmployeeDeferredCompensationDetails5</Role>
      <ShortName>Share-based awards (Details 3)</ShortName>
      <MenuCategory>Details</MenuCategory>
      <Position>149</Position>
    </Report>
    <Report instance="cs-20231231.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R150.htm</HtmlFileName>
      <LongName>43003 - Disclosure - ISU-type awards (Details 4)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.credit-suisse.com/role/DisclosureEmployeeDeferredCompensationDetails6</Role>
      <ShortName>ISU-type awards (Details 4)</ShortName>
      <MenuCategory>Details</MenuCategory>
      <Position>150</Position>
    </Report>
    <Report instance="cs-20231231.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R151.htm</HtmlFileName>
      <LongName>43004 - Disclosure - Cash-based awards (Details 5)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.credit-suisse.com/role/DisclosureEmployeeDeferredCompensationDetails7</Role>
      <ShortName>Cash-based awards (Details 5)</ShortName>
      <MenuCategory>Details</MenuCategory>
      <Position>151</Position>
    </Report>
    <Report instance="cs-20231231.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R152.htm</HtmlFileName>
      <LongName>43005 - Disclosure - Other variable compensation (Details 6)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.credit-suisse.com/role/DisclosureEmployeeDeferredCompensationDetails3</Role>
      <ShortName>Other variable compensation (Details 6)</ShortName>
      <MenuCategory>Details</MenuCategory>
      <Position>152</Position>
    </Report>
    <Report instance="cs-20231231.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R153.htm</HtmlFileName>
      <LongName>43100 - Disclosure - Related parties - Executive Board/Board of directors loans (Details)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.credit-suisse.com/role/DisclosureRelatedPartiesDetails</Role>
      <ShortName>Related parties - Executive Board/Board of directors loans (Details)</ShortName>
      <MenuCategory>Details</MenuCategory>
      <Position>153</Position>
    </Report>
    <Report instance="cs-20231231.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R154.htm</HtmlFileName>
      <LongName>43101 - Disclosure - Related parties - Liabilities to own pension funds (Details 2)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.credit-suisse.com/role/DisclosureRelatedPartiesDetails2</Role>
      <ShortName>Related parties - Liabilities to own pension funds (Details 2)</ShortName>
      <MenuCategory>Details</MenuCategory>
      <Position>154</Position>
    </Report>
    <Report instance="cs-20231231.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R155.htm</HtmlFileName>
      <LongName>43103 - Disclosure - Related parties - Bank (Details 4)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.credit-suisse.com/role/DisclosureRelatedPartiesDetails4</Role>
      <ShortName>Related parties - Bank (Details 4)</ShortName>
      <MenuCategory>Details</MenuCategory>
      <Position>155</Position>
    </Report>
    <Report instance="cs-20231231.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R156.htm</HtmlFileName>
      <LongName>43200 - Disclosure - Pension and other post-retirement benefits - Obligation and funded status (Details)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.credit-suisse.com/role/DisclosurePensionAndOtherPostRetirementBenefitsDetails</Role>
      <ShortName>Pension and other post-retirement benefits - Obligation and funded status (Details)</ShortName>
      <MenuCategory>Details</MenuCategory>
      <Position>156</Position>
    </Report>
    <Report instance="cs-20231231.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R157.htm</HtmlFileName>
      <LongName>43201 - Disclosure - Pension and other post-retirement benefits - PBO/ABO/Fair value (Details 2)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.credit-suisse.com/role/DisclosurePensionAndOtherPostRetirementBenefitsDetails2</Role>
      <ShortName>Pension and other post-retirement benefits - PBO/ABO/Fair value (Details 2)</ShortName>
      <MenuCategory>Details</MenuCategory>
      <Position>157</Position>
    </Report>
    <Report instance="cs-20231231.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R158.htm</HtmlFileName>
      <LongName>43202 - Disclosure - Pension and other post-retirement benefits - Plan assets measured at fair value (Details 3)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.credit-suisse.com/role/DisclosurePensionAndOtherPostRetirementBenefitsDetails3</Role>
      <ShortName>Pension and other post-retirement benefits - Plan assets measured at fair value (Details 3)</ShortName>
      <MenuCategory>Details</MenuCategory>
      <Position>158</Position>
    </Report>
    <Report instance="cs-20231231.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R159.htm</HtmlFileName>
      <LongName>43203 - Disclosure - Pension and other post-retirement benefits - Plan assets measured at fair value roll-forward (Details 4)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.credit-suisse.com/role/DisclosurePensionAndOtherPostRetirementBenefitsDetails4</Role>
      <ShortName>Pension and other post-retirement benefits - Plan assets measured at fair value roll-forward (Details 4)</ShortName>
      <MenuCategory>Details</MenuCategory>
      <Position>159</Position>
    </Report>
    <Report instance="cs-20231231.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R160.htm</HtmlFileName>
      <LongName>43204 - Disclosure - Pension and other post-retirement benefits - Weighted-average assumptions (Details 5)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.credit-suisse.com/role/DisclosurePensionAndOtherPostRetirementBenefitsDetails5</Role>
      <ShortName>Pension and other post-retirement benefits - Weighted-average assumptions (Details 5)</ShortName>
      <MenuCategory>Details</MenuCategory>
      <Position>160</Position>
    </Report>
    <Report instance="cs-20231231.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R161.htm</HtmlFileName>
      <LongName>43205 - Disclosure - Pension and other post-retirement benefits - Estimated future benefit payments (Details 6)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.credit-suisse.com/role/DisclosurePensionAndOtherPostRetirementBenefitsDetails6</Role>
      <ShortName>Pension and other post-retirement benefits - Estimated future benefit payments (Details 6)</ShortName>
      <MenuCategory>Details</MenuCategory>
      <Position>161</Position>
    </Report>
    <Report instance="cs-20231231.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R162.htm</HtmlFileName>
      <LongName>43206 - Disclosure - Pension and other post-retirement benefits - Contributions (Details 7)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.credit-suisse.com/role/DisclosurePensionAndOtherPostRetirementBenefitsDetails7</Role>
      <ShortName>Pension and other post-retirement benefits - Contributions (Details 7)</ShortName>
      <MenuCategory>Details</MenuCategory>
      <Position>162</Position>
    </Report>
    <Report instance="cs-20231231.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R163.htm</HtmlFileName>
      <LongName>43208 - Disclosure - Pension and other post-retirement benefits - Mortality tables and life expectancies (Details 9)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.credit-suisse.com/role/DisclosurePensionAndOtherPostRetirementBenefitsDetails9</Role>
      <ShortName>Pension and other post-retirement benefits - Mortality tables and life expectancies (Details 9)</ShortName>
      <MenuCategory>Details</MenuCategory>
      <Position>163</Position>
    </Report>
    <Report instance="cs-20231231.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R164.htm</HtmlFileName>
      <LongName>43210 - Disclosure - Pension and other post-retirement benefits (Details 11)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.credit-suisse.com/role/DisclosurePensionAndOtherPostRetirementBenefitsDetails11</Role>
      <ShortName>Pension and other post-retirement benefits (Details 11)</ShortName>
      <MenuCategory>Details</MenuCategory>
      <ParentRole>http://www.credit-suisse.com/role/DisclosurePensionAndOtherPostRetirementBenefitsTables</ParentRole>
      <Position>164</Position>
    </Report>
    <Report instance="cs-20231231.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R165.htm</HtmlFileName>
      <LongName>43300 - Disclosure - Derivatives and hedging activities - Fair value - balance sheet related (Details)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.credit-suisse.com/role/DisclosureDerivativesAndHedgingActivitiesDetails</Role>
      <ShortName>Derivatives and hedging activities - Fair value - balance sheet related (Details)</ShortName>
      <MenuCategory>Details</MenuCategory>
      <Position>165</Position>
    </Report>
    <Report instance="cs-20231231.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R166.htm</HtmlFileName>
      <LongName>43301 - Disclosure - Derivatives and hedging activities - Movements (Details 2)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.credit-suisse.com/role/DisclosureDerivativesAndHedgingActivitiesDetails2</Role>
      <ShortName>Derivatives and hedging activities - Movements (Details 2)</ShortName>
      <MenuCategory>Details</MenuCategory>
      <Position>166</Position>
    </Report>
    <Report instance="cs-20231231.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R167.htm</HtmlFileName>
      <LongName>43302 - Disclosure - Derivatives and hedging activities - Contingent credit risk (Details 3)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.credit-suisse.com/role/DisclosureDerivativesAndHedgingActivitiesDetails3</Role>
      <ShortName>Derivatives and hedging activities - Contingent credit risk (Details 3)</ShortName>
      <MenuCategory>Details</MenuCategory>
      <Position>167</Position>
    </Report>
    <Report instance="cs-20231231.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R168.htm</HtmlFileName>
      <LongName>43303 - Disclosure - Derivatives and hedging activities - Credit protection sold/purchased (Details 4)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.credit-suisse.com/role/DisclosureDerivativesAndHedgingActivitiesDetails4</Role>
      <ShortName>Derivatives and hedging activities - Credit protection sold/purchased (Details 4)</ShortName>
      <MenuCategory>Details</MenuCategory>
      <Position>168</Position>
    </Report>
    <Report instance="cs-20231231.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R169.htm</HtmlFileName>
      <LongName>43304 - Disclosure - Derivatives and hedging activities - Credit derivatives (Details 5)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.credit-suisse.com/role/DisclosureDerivativesAndHedgingActivitiesDetails5</Role>
      <ShortName>Derivatives and hedging activities - Credit derivatives (Details 5)</ShortName>
      <MenuCategory>Details</MenuCategory>
      <Position>169</Position>
    </Report>
    <Report instance="cs-20231231.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R170.htm</HtmlFileName>
      <LongName>43305 - Disclosure - Derivatives and hedging activities (Details 6)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.credit-suisse.com/role/DisclosureDerivativesAndHedgingActivitiesDetails6</Role>
      <ShortName>Derivatives and hedging activities (Details 6)</ShortName>
      <MenuCategory>Details</MenuCategory>
      <ParentRole>http://www.credit-suisse.com/role/DisclosureDerivativesAndHedgingActivitiesTables</ParentRole>
      <Position>170</Position>
    </Report>
    <Report instance="cs-20231231.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R171.htm</HtmlFileName>
      <LongName>43400 - Disclosure - Guarantees and commitments - Guarantees maturity (Details)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.credit-suisse.com/role/DisclosureGuaranteesAndCommitmentsDetails</Role>
      <ShortName>Guarantees and commitments - Guarantees maturity (Details)</ShortName>
      <MenuCategory>Details</MenuCategory>
      <Position>171</Position>
    </Report>
    <Report instance="cs-20231231.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R172.htm</HtmlFileName>
      <LongName>43401 - Disclosure - Guarantees and commitments - Other guarantees (Details 2)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.credit-suisse.com/role/DisclosureGuaranteesAndCommitmentsDetails2</Role>
      <ShortName>Guarantees and commitments - Other guarantees (Details 2)</ShortName>
      <MenuCategory>Details</MenuCategory>
      <Position>172</Position>
    </Report>
    <Report instance="cs-20231231.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R173.htm</HtmlFileName>
      <LongName>43406 - Disclosure - Guarantees and commitments - Other commitments maturity (Details 7)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.credit-suisse.com/role/DisclosureGuaranteesAndCommitmentsDetails7</Role>
      <ShortName>Guarantees and commitments - Other commitments maturity (Details 7)</ShortName>
      <MenuCategory>Details</MenuCategory>
      <Position>173</Position>
    </Report>
    <Report instance="cs-20231231.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R174.htm</HtmlFileName>
      <LongName>43500 - Disclosure - Transfers of financial assets (TFA) - Securitizations (Details)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.credit-suisse.com/role/DisclosureTransfersOfFinancialAssetsAndVariableInterestEntitiesDetails</Role>
      <ShortName>Transfers of financial assets (TFA) - Securitizations (Details)</ShortName>
      <MenuCategory>Details</MenuCategory>
      <ParentRole>http://www.credit-suisse.com/role/DisclosureTransfersOfFinancialAssetsAndVariableInterestEntitiesTables</ParentRole>
      <Position>174</Position>
    </Report>
    <Report instance="cs-20231231.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R175.htm</HtmlFileName>
      <LongName>43501 - Disclosure - TFA - Principal amounts outstanding / total assets - continuing involvement (Details 2)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.credit-suisse.com/role/DisclosureTransfersOfFinancialAssetsAndVariableInterestEntitiesDetails2</Role>
      <ShortName>TFA - Principal amounts outstanding / total assets - continuing involvement (Details 2)</ShortName>
      <MenuCategory>Details</MenuCategory>
      <Position>175</Position>
    </Report>
    <Report instance="cs-20231231.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R176.htm</HtmlFileName>
      <LongName>43502 - Disclosure - TFA - Key economic assumptions at time of transfer (Details 3)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.credit-suisse.com/role/DisclosureTransfersOfFinancialAssetsAndVariableInterestEntitiesDetails3</Role>
      <ShortName>TFA - Key economic assumptions at time of transfer (Details 3)</ShortName>
      <MenuCategory>Details</MenuCategory>
      <Position>176</Position>
    </Report>
    <Report instance="cs-20231231.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R177.htm</HtmlFileName>
      <LongName>43503 - Disclosure - TFA - Key economic assumptions at balance sheet date (Details 4)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.credit-suisse.com/role/DisclosureTransfersOfFinancialAssetsAndVariableInterestEntitiesDetails4</Role>
      <ShortName>TFA - Key economic assumptions at balance sheet date (Details 4)</ShortName>
      <MenuCategory>Details</MenuCategory>
      <Position>177</Position>
    </Report>
    <Report instance="cs-20231231.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R178.htm</HtmlFileName>
      <LongName>43504 - Disclosure - TFA - Carrying amounts for sale treatmen not achieved (Details 5)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.credit-suisse.com/role/DisclosureTransfersOfFinancialAssetsAndVariableInterestEntitiesDetails5</Role>
      <ShortName>TFA - Carrying amounts for sale treatmen not achieved (Details 5)</ShortName>
      <MenuCategory>Details</MenuCategory>
      <Position>178</Position>
    </Report>
    <Report instance="cs-20231231.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R179.htm</HtmlFileName>
      <LongName>43505 - Disclosure - TFA - Transfer of certain financial assets accounted for as secured borrowings (Details 6)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.credit-suisse.com/role/DisclosureTransfersOfFinancialAssetsAndVariableInterestEntitiesDetails7</Role>
      <ShortName>TFA - Transfer of certain financial assets accounted for as secured borrowings (Details 6)</ShortName>
      <MenuCategory>Details</MenuCategory>
      <Position>179</Position>
    </Report>
    <Report instance="cs-20231231.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R180.htm</HtmlFileName>
      <LongName>43506 - Disclosure - Variable interest entities (VIE) - Consolidated (Details 7)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.credit-suisse.com/role/DisclosureTransfersOfFinancialAssetsAndVariableInterestEntitiesDetails8</Role>
      <ShortName>Variable interest entities (VIE) - Consolidated (Details 7)</ShortName>
      <MenuCategory>Details</MenuCategory>
      <Position>180</Position>
    </Report>
    <Report instance="cs-20231231.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R181.htm</HtmlFileName>
      <LongName>43507 - Disclosure - VIE - Non-consolidated (Details 8)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.credit-suisse.com/role/DisclosureTransfersOfFinancialAssetsAndVariableInterestEntitiesDetails9</Role>
      <ShortName>VIE - Non-consolidated (Details 8)</ShortName>
      <MenuCategory>Details</MenuCategory>
      <Position>181</Position>
    </Report>
    <Report instance="cs-20231231.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R182.htm</HtmlFileName>
      <LongName>43601 - Disclosure - Financial instruments (FI) - Assets measured at fair value (Details 2)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.credit-suisse.com/role/DisclosureFinancialInstrumentsDetails2</Role>
      <ShortName>Financial instruments (FI) - Assets measured at fair value (Details 2)</ShortName>
      <MenuCategory>Details</MenuCategory>
      <ParentRole>http://www.credit-suisse.com/role/DisclosureFinancialInstrumentsTables</ParentRole>
      <Position>182</Position>
    </Report>
    <Report instance="cs-20231231.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R183.htm</HtmlFileName>
      <LongName>43603 - Disclosure - FI - Liabilities measured at fair value (Details 3)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.credit-suisse.com/role/DisclosureFinancialInstrumentsDetails3</Role>
      <ShortName>FI - Liabilities measured at fair value (Details 3)</ShortName>
      <MenuCategory>Details</MenuCategory>
      <Position>183</Position>
    </Report>
    <Report instance="cs-20231231.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R184.htm</HtmlFileName>
      <LongName>43604 - Disclosure - FI - Roll-forward of assets measured at fair value on recurring basis (Details 4)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.credit-suisse.com/role/DisclosureFinancialInstrumentsDetails4</Role>
      <ShortName>FI - Roll-forward of assets measured at fair value on recurring basis (Details 4)</ShortName>
      <MenuCategory>Details</MenuCategory>
      <Position>184</Position>
    </Report>
    <Report instance="cs-20231231.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R185.htm</HtmlFileName>
      <LongName>43605 - Disclosure - FI - Roll-forward of liabilities measured at fair value on recurring basis (Details 5)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.credit-suisse.com/role/DisclosureFinancialInstrumentsDetails5</Role>
      <ShortName>FI - Roll-forward of liabilities measured at fair value on recurring basis (Details 5)</ShortName>
      <MenuCategory>Details</MenuCategory>
      <Position>185</Position>
    </Report>
    <Report instance="cs-20231231.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R186.htm</HtmlFileName>
      <LongName>43607 - Disclosure - FI - Roll-forward of net assets measured at fair value on recurring basis (Details 7)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.credit-suisse.com/role/DisclosureFinancialInstrumentsDetails6</Role>
      <ShortName>FI - Roll-forward of net assets measured at fair value on recurring basis (Details 7)</ShortName>
      <MenuCategory>Details</MenuCategory>
      <Position>186</Position>
    </Report>
    <Report instance="cs-20231231.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R187.htm</HtmlFileName>
      <LongName>43610 - Disclosure - FI - Difference between fair value and unpaid principle balances (Details 10)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.credit-suisse.com/role/DisclosureFinancialInstrumentsDetails9</Role>
      <ShortName>FI - Difference between fair value and unpaid principle balances (Details 10)</ShortName>
      <MenuCategory>Details</MenuCategory>
      <Position>187</Position>
    </Report>
    <Report instance="cs-20231231.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R188.htm</HtmlFileName>
      <LongName>43611 - Disclosure - FI - Gains/losses on financial instruments (Details 11)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.credit-suisse.com/role/DisclosureFinancialInstrumentsDetails10</Role>
      <ShortName>FI - Gains/losses on financial instruments (Details 11)</ShortName>
      <MenuCategory>Details</MenuCategory>
      <Position>188</Position>
    </Report>
    <Report instance="cs-20231231.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R189.htm</HtmlFileName>
      <LongName>43612 - Disclosure - FI - Fair value, unfunded commitments, term of redemption conditions (Details 12)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.credit-suisse.com/role/DisclosureFinancialInstrumentsDetails11</Role>
      <ShortName>FI - Fair value, unfunded commitments, term of redemption conditions (Details 12)</ShortName>
      <MenuCategory>Details</MenuCategory>
      <Position>189</Position>
    </Report>
    <Report instance="cs-20231231.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R190.htm</HtmlFileName>
      <LongName>43614 - Disclosure - FI - Quantitative information about level 3 assets at fair value (Details 14)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.credit-suisse.com/role/DisclosureFinancialInstrumentsDetails15</Role>
      <ShortName>FI - Quantitative information about level 3 assets at fair value (Details 14)</ShortName>
      <MenuCategory>Details</MenuCategory>
      <Position>190</Position>
    </Report>
    <Report instance="cs-20231231.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R191.htm</HtmlFileName>
      <LongName>43615 - Disclosure - FI - Quantitative information about level 3 liabilities at fair value (Details 15)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.credit-suisse.com/role/DisclosureFinancialInstrumentsDetails16</Role>
      <ShortName>FI - Quantitative information about level 3 liabilities at fair value (Details 15)</ShortName>
      <MenuCategory>Details</MenuCategory>
      <Position>191</Position>
    </Report>
    <Report instance="cs-20231231.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R192.htm</HtmlFileName>
      <LongName>43616 - Disclosure - FI - Carrying value and fair value not held at fair value (Details 16)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.credit-suisse.com/role/DisclosureFinancialInstrumentsDetails17</Role>
      <ShortName>FI - Carrying value and fair value not held at fair value (Details 16)</ShortName>
      <MenuCategory>Details</MenuCategory>
      <Position>192</Position>
    </Report>
    <Report instance="cs-20231231.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R193.htm</HtmlFileName>
      <LongName>43617 - Disclosure - FI - Own credit gains/(losses) on fair value option elected instruments (Details 17)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.credit-suisse.com/role/DisclosureFinancialInstrumentsDetails18</Role>
      <ShortName>FI - Own credit gains/(losses) on fair value option elected instruments (Details 17)</ShortName>
      <MenuCategory>Details</MenuCategory>
      <Position>193</Position>
    </Report>
    <Report instance="cs-20231231.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R194.htm</HtmlFileName>
      <LongName>43700 - Disclosure - Assets pledged and collateral (Details)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.credit-suisse.com/role/DisclosureAssetsPledgedOrAssignedDetails</Role>
      <ShortName>Assets pledged and collateral (Details)</ShortName>
      <MenuCategory>Details</MenuCategory>
      <ParentRole>http://www.credit-suisse.com/role/DisclosureAssetsPledgedOrAssignedTables</ParentRole>
      <Position>194</Position>
    </Report>
    <Report instance="cs-20231231.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R195.htm</HtmlFileName>
      <LongName>43800 - Disclosure - Capital adequacy (Details)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.credit-suisse.com/role/DisclosureCapitalAdequacyDetails</Role>
      <ShortName>Capital adequacy (Details)</ShortName>
      <MenuCategory>Details</MenuCategory>
      <ParentRole>http://www.credit-suisse.com/role/DisclosureCapitalAdequacyTables</ParentRole>
      <Position>195</Position>
    </Report>
    <Report instance="cs-20231231.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R196.htm</HtmlFileName>
      <LongName>43900 - Disclosure - Assets under management (Details)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.credit-suisse.com/role/DisclosureAssetsUnderManagementDetails</Role>
      <ShortName>Assets under management (Details)</ShortName>
      <MenuCategory>Details</MenuCategory>
      <ParentRole>http://www.credit-suisse.com/role/DisclosureAssetsUnderManagementTables</ParentRole>
      <Position>196</Position>
    </Report>
    <Report instance="cs-20231231.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R197.htm</HtmlFileName>
      <LongName>43901 - Disclosure - Assets under management - Change (Details 2)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.credit-suisse.com/role/DisclosureAssetsUnderManagementDetails2</Role>
      <ShortName>Assets under management - Change (Details 2)</ShortName>
      <MenuCategory>Details</MenuCategory>
      <Position>197</Position>
    </Report>
    <Report instance="cs-20231231.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R198.htm</HtmlFileName>
      <LongName>44000 - Disclosure - Litigation (Details)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.credit-suisse.com/role/DisclosureLitigationDetails</Role>
      <ShortName>Litigation (Details)</ShortName>
      <MenuCategory>Details</MenuCategory>
      <ParentRole>http://www.credit-suisse.com/role/DisclosureLitigationTables</ParentRole>
      <Position>198</Position>
    </Report>
    <Report instance="cs-20231231.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R199.htm</HtmlFileName>
      <LongName>44001 - Disclosure - Litigation (Details 1)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.credit-suisse.com/role/DisclosureLitigationDetails1</Role>
      <ShortName>Litigation (Details 1)</ShortName>
      <MenuCategory>Details</MenuCategory>
      <ParentRole>http://www.credit-suisse.com/role/DisclosureLitigationTables</ParentRole>
      <Position>199</Position>
    </Report>
    <Report instance="cs-20231231.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R200.htm</HtmlFileName>
      <LongName>44100 - Disclosure - Significant subsidiaries and equity method investments (Details)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.credit-suisse.com/role/DisclosureSignificantSubsidiariesAndEquityMethodInvestmentsDetails</Role>
      <ShortName>Significant subsidiaries and equity method investments (Details)</ShortName>
      <MenuCategory>Details</MenuCategory>
      <ParentRole>http://www.credit-suisse.com/role/DisclosureSignificantSubsidiariesAndEquityMethodInvestmentsTables</ParentRole>
      <Position>200</Position>
    </Report>
    <Report instance="cs-20231231.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R201.htm</HtmlFileName>
      <LongName>44300 - Disclosure - Significant valuation and income recognition differences between US GAAP and - Swiss GAAP banking law (Details)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.credit-suisse.com/role/DisclosureSignificantValuationAndIncomeRecognitionDifferencesBetweenUSGAAPAndSwissGAAPBankingLawDetails</Role>
      <ShortName>Significant valuation and income recognition differences between US GAAP and - Swiss GAAP banking law (Details)</ShortName>
      <MenuCategory>Details</MenuCategory>
      <Position>201</Position>
    </Report>
    <Report>
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <LongName>All Reports</LongName>
      <ReportType>Book</ReportType>
      <ShortName>All Reports</ShortName>
    </Report>
  </MyReports>
  <Logs>
    <Log type="Warning">[ix-0514-Hidden-Fact-Eligible-For-Transform] WARN: 10 fact(s) appearing in ix:hidden were eligible for transformation: cs:MinimumTotalCompensationOfEmployeesToWhomShareAwardsAreGranted, cs:OtherFinancialAssetsAtAmortizedCostPastDue, us-gaap:FinancingReceivableRecordedInvestment90DaysPastDueAndStillAccruing, us-gaap:HeldToMaturitySecurities, us-gaap:PropertyPlantAndEquipmentUsefulLife -  cs-20231231.htm 1</Log>
    <Log type="Warning">[dqc-0008-Reversed-Calculation] The calculation in the extension taxonomy from us-gaap:DerivativeLiabilities to us-gaap:DerivativeFairValueOfDerivativeLiabilityAmountOffsetAgainstCollateral in 42801 - Disclosure - Offsetting of financial liabilities (Details 2) is the opposite of a calculation defined in the base US GAAP taxonomy. Check that the calculation is correct or that you have used the correct tag for the two elements identified in the calculation. It is possible that the calculation is correct in the case of a reconciliation calculation. Rule Element Id: 6819. cs-20231231_cal.xml 863</Log>
    <Log type="Warning">[dqc-0015-Negative-Values] Fact us-gaap:InterestExpenseShortTermBorrowingsExcludingFederalFundsAndSecuritiesSoldUnderAgreementsToRepurchase has a value of -3000000 which is less than zero. This element should not have a negative value. The preparer should consider if the value is input correctly for this assertion and, after considering the appropriateness of the input, if incorrect, input the amount as a positive (i.e., absolute) value and provide a negated label. The properties of this us-gaap:InterestExpenseShortTermBorrowingsExcludingFederalFundsAndSecuritiesSoldUnderAgreementsToRepurchase fact are: Context: AR_D-CurrentYear-2, Unit: CHF, Rule Element Id: 1393. cs-20231231.htm 1</Log>
    <Log type="Warning">[dqc-0015-Negative-Values] Fact us-gaap:DeferredTaxAssetsLiabilitiesNet has a value of -42000000 which is less than zero. This element should not have a negative value. The preparer should consider if the value is input correctly for this assertion and, after considering the appropriateness of the input, if incorrect, input the amount as a positive (i.e., absolute) value and provide a negated label. The properties of this us-gaap:DeferredTaxAssetsLiabilitiesNet fact are: Context: AR-Q_I-CurrentPeriodEnd, Unit: CHF, Rule Element Id: 623. cs-20231231.htm 1</Log>
    <Log type="Warning">[dqc-0015-Negative-Values] Fact us-gaap:DeferredTaxAssetsLiabilitiesNet has a value of -411000000 which is less than zero. This element should not have a negative value. The preparer should consider if the value is input correctly for this assertion and, after considering the appropriateness of the input, if incorrect, input the amount as a positive (i.e., absolute) value and provide a negated label. The properties of this us-gaap:DeferredTaxAssetsLiabilitiesNet fact are: Context: AR-Q_I-CurrentYearEnd-1, Unit: CHF, Rule Element Id: 623. cs-20231231.htm 1</Log>
    <Log type="Warning">[dqc-0015-Negative-Values] Fact us-gaap:FairValueMeasurementWithUnobservableInputsReconciliationLiabilityTransfersIntoLevel3 has a value of -1000000 which is less than zero. This element should not have a negative value. The preparer should consider if the value is input correctly for this assertion and, after considering the appropriateness of the input, if incorrect, input the amount as a positive (i.e., absolute) value and provide a negated label. The properties of this us-gaap:FairValueMeasurementWithUnobservableInputsReconciliationLiabilityTransfersIntoLevel3 fact are: Context: AR-Q_D-YTDCurrentYear_cs-4Q23FairValueAssetsAndLiabilitiesMeasuredOnRecurringBasisUnobservableInputReconciliationByTypeAxis_us-gaap-2023TradingLiabilitiesMember_us-gaap-2023FairValueByLiabilityClassAxis_us-gaap-2023OtherLiabilitiesMember_us-gaap-2023FairValueByMeasurementFrequencyAxis_us-gaap-2023FairValueMeasurementsRecurringMember, Unit: CHF, Rule Element Id: 1032. cs-20231231.htm 1</Log>
    <Log type="Warning">[DQC.US.0057.9728] One of the following elements CashCashEquivalentsRestrictedCashAndRestrictedCashEquivalents, CashCashEquivalentsRestrictedCashAndRestrictedCashEquivalentsIncludingDisposalGroupAndDiscontinuedOperations should appear as the opening and closing balance in the cash flow statement using the group http://www.credit-suisse.com/role/CashFlows. Instead the following balance items have been used in this statement CashAndCashEquivalentsAtCarryingValue. Due to the implementaion of ASU-2016-18 at least one of the opening and closing balance items listed must be used in the cash flow statement. - https://xbrl.fasb.org/us-gaap/2023/elts/us-gaap-2023.xsd 1778 - https://xbrl.fasb.org/us-gaap/2023/elts/us-gaap-2023.xsd 1778</Log>
    <Log type="Warning">[DQC.US.0070.7645] The concept DefinedBenefitPlanFairValueOfPlanAssets with a defaulted value of 1076000000.000000 is not equal to the aggregated value of the dimensionally qualified components on the axis DefinedBenefitPlanByPlanAssetCategoriesAxis which has an aggregate value of 2106000000.000000 based on the data in the filing.
The aggregated value is calculated by adding the members in the network http://www.credit-suisse.com/role/DisclosurePensionAndOtherPostRetirementBenefitsDetails3. The values of the calculation components are as follows:
0, 0, 1030000000, 46000000, 0, 0, 1030000000, 0.

The value of a concept broken down by its components along the DefinedBenefitPlanByPlanAssetCategoriesAxis axis should  be equal to its component pieces. An error could occur for one of the following reasons:

1. The values of the plan assets by category have been further disaggregated by additional dimensions such as geography. Plan Asset categories should not be dimensionally disaggregated and members should be defined for each security class reported. i.e. Equity Securities in the US should be represented as a single member.

2. The  default value of DefinedBenefitPlanFairValueOfPlanAssets is incorrectly totaled for DefinedBenefitPlanFairValueOfPlanAssets

 3. Not all dimension members or additional dimensions have been defined on the category axis DefinedBenefitPlanByPlanAssetCategoriesAxis.

4. The filer has reported a sub component of plan assets that does not represent a complete breakdown of the total. In these cases the element DefinedBenefitPlanPlanAssetsInvestmentWithinPlanAssetCategoryAmount should be used instead of the element DefinedBenefitPlanFairValueOfPlanAssets.

This rule aggregates the value of member components located on the axis at the highest level of aggregation to avoid double counting in the event that the company uses a hierarchy of members.

The properties of this DefinedBenefitPlanFairValueOfPlanAssets fact are:
Context: AR_I-CurrentYearEnd_us-gaap-2023FairValueByFairValueHierarchyLevelAxis_us-gaap-2023FairValueInputsLevel1Member_us-gaap-2023RetirementPlanSponsorLocationAxis_us-gaap-2023ForeignPlanMember_us-gaap-2023RetirementPlanTypeAxis_us-gaap-2023PensionPlansDefinedBenefitMember
Unit: CHF. - cs-20231231.htm 1 - cs-20231231.htm 1</Log>
    <Log type="Warning">[DQC.US.0070.7645] The concept DefinedBenefitPlanFairValueOfPlanAssets with a defaulted value of 2166000000.000000 is not equal to the aggregated value of the dimensionally qualified components on the axis DefinedBenefitPlanByPlanAssetCategoriesAxis which has an aggregate value of 3943000000.000000 based on the data in the filing.
The aggregated value is calculated by adding the members in the network http://www.credit-suisse.com/role/DisclosurePensionAndOtherPostRetirementBenefitsDetails3. The values of the calculation components are as follows:
70000000, 1030000000, 757000000, 74000000, 245000000, -10000000, -10000000, 1787000000.

The value of a concept broken down by its components along the DefinedBenefitPlanByPlanAssetCategoriesAxis axis should  be equal to its component pieces. An error could occur for one of the following reasons:

1. The values of the plan assets by category have been further disaggregated by additional dimensions such as geography. Plan Asset categories should not be dimensionally disaggregated and members should be defined for each security class reported. i.e. Equity Securities in the US should be represented as a single member.

2. The  default value of DefinedBenefitPlanFairValueOfPlanAssets is incorrectly totaled for DefinedBenefitPlanFairValueOfPlanAssets

 3. Not all dimension members or additional dimensions have been defined on the category axis DefinedBenefitPlanByPlanAssetCategoriesAxis.

4. The filer has reported a sub component of plan assets that does not represent a complete breakdown of the total. In these cases the element DefinedBenefitPlanPlanAssetsInvestmentWithinPlanAssetCategoryAmount should be used instead of the element DefinedBenefitPlanFairValueOfPlanAssets.

This rule aggregates the value of member components located on the axis at the highest level of aggregation to avoid double counting in the event that the company uses a hierarchy of members.

The properties of this DefinedBenefitPlanFairValueOfPlanAssets fact are:
Context: AR_I-CurrentYearEnd_us-gaap-2023RetirementPlanSponsorLocationAxis_us-gaap-2023ForeignPlanMember_us-gaap-2023RetirementPlanTypeAxis_us-gaap-2023PensionPlansDefinedBenefitMember
Unit: CHF. - cs-20231231.htm 1 - cs-20231231.htm 1</Log>
    <Log type="Warning">[DQC.US.0070.7645] The concept DefinedBenefitPlanFairValueOfPlanAssets with a defaulted value of 774000000.000000 is not equal to the aggregated value of the dimensionally qualified components on the axis DefinedBenefitPlanByPlanAssetCategoriesAxis which has an aggregate value of 1221000000.000000 based on the data in the filing.
The aggregated value is calculated by adding the members in the network http://www.credit-suisse.com/role/DisclosurePensionAndOtherPostRetirementBenefitsDetails3. The values of the calculation components are as follows:
457000000, 74000000, -10000000, 199000000, 457000000, 54000000, 0, -10000000.

The value of a concept broken down by its components along the DefinedBenefitPlanByPlanAssetCategoriesAxis axis should  be equal to its component pieces. An error could occur for one of the following reasons:

1. The values of the plan assets by category have been further disaggregated by additional dimensions such as geography. Plan Asset categories should not be dimensionally disaggregated and members should be defined for each security class reported. i.e. Equity Securities in the US should be represented as a single member.

2. The  default value of DefinedBenefitPlanFairValueOfPlanAssets is incorrectly totaled for DefinedBenefitPlanFairValueOfPlanAssets

 3. Not all dimension members or additional dimensions have been defined on the category axis DefinedBenefitPlanByPlanAssetCategoriesAxis.

4. The filer has reported a sub component of plan assets that does not represent a complete breakdown of the total. In these cases the element DefinedBenefitPlanPlanAssetsInvestmentWithinPlanAssetCategoryAmount should be used instead of the element DefinedBenefitPlanFairValueOfPlanAssets.

This rule aggregates the value of member components located on the axis at the highest level of aggregation to avoid double counting in the event that the company uses a hierarchy of members.

The properties of this DefinedBenefitPlanFairValueOfPlanAssets fact are:
Context: AR_I-CurrentYearEnd_us-gaap-2023FairValueByFairValueHierarchyLevelAxis_us-gaap-2023FairValueInputsLevel2Member_us-gaap-2023RetirementPlanSponsorLocationAxis_us-gaap-2023ForeignPlanMember_us-gaap-2023RetirementPlanTypeAxis_us-gaap-2023PensionPlansDefinedBenefitMember
Unit: CHF. - cs-20231231.htm 1 - cs-20231231.htm 1</Log>
    <Log type="Warning">[DQC.US.0070.7645] The concept DefinedBenefitPlanFairValueOfPlanAssets with a defaulted value of 1250000000.000000 is not equal to the aggregated value of the dimensionally qualified components on the axis DefinedBenefitPlanByPlanAssetCategoriesAxis which has an aggregate value of 2472000000.000000 based on the data in the filing.
The aggregated value is calculated by adding the members in the network http://www.credit-suisse.com/role/DisclosurePensionAndOtherPostRetirementBenefitsDetails3. The values of the calculation components are as follows:
1222000000, 0, 28000000, 0, 0, 0, 1222000000, 0.

The value of a concept broken down by its components along the DefinedBenefitPlanByPlanAssetCategoriesAxis axis should  be equal to its component pieces. An error could occur for one of the following reasons:

1. The values of the plan assets by category have been further disaggregated by additional dimensions such as geography. Plan Asset categories should not be dimensionally disaggregated and members should be defined for each security class reported. i.e. Equity Securities in the US should be represented as a single member.

2. The  default value of DefinedBenefitPlanFairValueOfPlanAssets is incorrectly totaled for DefinedBenefitPlanFairValueOfPlanAssets

 3. Not all dimension members or additional dimensions have been defined on the category axis DefinedBenefitPlanByPlanAssetCategoriesAxis.

4. The filer has reported a sub component of plan assets that does not represent a complete breakdown of the total. In these cases the element DefinedBenefitPlanPlanAssetsInvestmentWithinPlanAssetCategoryAmount should be used instead of the element DefinedBenefitPlanFairValueOfPlanAssets.

This rule aggregates the value of member components located on the axis at the highest level of aggregation to avoid double counting in the event that the company uses a hierarchy of members.

The properties of this DefinedBenefitPlanFairValueOfPlanAssets fact are:
Context: AR_I-CurrentYearEnd-1_us-gaap-2023FairValueByFairValueHierarchyLevelAxis_us-gaap-2023FairValueInputsLevel1Member_us-gaap-2023RetirementPlanSponsorLocationAxis_us-gaap-2023ForeignPlanMember_us-gaap-2023RetirementPlanTypeAxis_us-gaap-2023PensionPlansDefinedBenefitMember
Unit: CHF. - cs-20231231.htm 1 - cs-20231231.htm 1</Log>
    <Log type="Warning">[DQC.US.0070.7645] The concept DefinedBenefitPlanFairValueOfPlanAssets with a defaulted value of 695000000.000000 is not equal to the aggregated value of the dimensionally qualified components on the axis DefinedBenefitPlanByPlanAssetCategoriesAxis which has an aggregate value of 1158000000.000000 based on the data in the filing.
The aggregated value is calculated by adding the members in the network http://www.credit-suisse.com/role/DisclosurePensionAndOtherPostRetirementBenefitsDetails3. The values of the calculation components are as follows:
-59000000, 44000000, 81000000, 90000000, 478000000, 522000000, 61000000, -59000000.

The value of a concept broken down by its components along the DefinedBenefitPlanByPlanAssetCategoriesAxis axis should  be equal to its component pieces. An error could occur for one of the following reasons:

1. The values of the plan assets by category have been further disaggregated by additional dimensions such as geography. Plan Asset categories should not be dimensionally disaggregated and members should be defined for each security class reported. i.e. Equity Securities in the US should be represented as a single member.

2. The  default value of DefinedBenefitPlanFairValueOfPlanAssets is incorrectly totaled for DefinedBenefitPlanFairValueOfPlanAssets

 3. Not all dimension members or additional dimensions have been defined on the category axis DefinedBenefitPlanByPlanAssetCategoriesAxis.

4. The filer has reported a sub component of plan assets that does not represent a complete breakdown of the total. In these cases the element DefinedBenefitPlanPlanAssetsInvestmentWithinPlanAssetCategoryAmount should be used instead of the element DefinedBenefitPlanFairValueOfPlanAssets.

This rule aggregates the value of member components located on the axis at the highest level of aggregation to avoid double counting in the event that the company uses a hierarchy of members.

The properties of this DefinedBenefitPlanFairValueOfPlanAssets fact are:
Context: AR_I-CurrentYearEnd-1_us-gaap-2023FairValueByFairValueHierarchyLevelAxis_us-gaap-2023FairValueInputsLevel2Member_us-gaap-2023RetirementPlanSponsorLocationAxis_us-gaap-2023ForeignPlanMember_us-gaap-2023RetirementPlanTypeAxis_us-gaap-2023PensionPlansDefinedBenefitMember
Unit: CHF. - cs-20231231.htm 1 - cs-20231231.htm 1</Log>
    <Log type="Warning">[DQC.US.0070.7645] The concept DefinedBenefitPlanFairValueOfPlanAssets with a defaulted value of 2316000000.000000 is not equal to the aggregated value of the dimensionally qualified components on the axis DefinedBenefitPlanByPlanAssetCategoriesAxis which has an aggregate value of 4327000000.000000 based on the data in the filing.
The aggregated value is calculated by adding the members in the network http://www.credit-suisse.com/role/DisclosurePensionAndOtherPostRetirementBenefitsDetails3. The values of the calculation components are as follows:
-59000000, -59000000, 1266000000, 81000000, 118000000, 804000000, 2070000000, 106000000.

The value of a concept broken down by its components along the DefinedBenefitPlanByPlanAssetCategoriesAxis axis should  be equal to its component pieces. An error could occur for one of the following reasons:

1. The values of the plan assets by category have been further disaggregated by additional dimensions such as geography. Plan Asset categories should not be dimensionally disaggregated and members should be defined for each security class reported. i.e. Equity Securities in the US should be represented as a single member.

2. The  default value of DefinedBenefitPlanFairValueOfPlanAssets is incorrectly totaled for DefinedBenefitPlanFairValueOfPlanAssets

 3. Not all dimension members or additional dimensions have been defined on the category axis DefinedBenefitPlanByPlanAssetCategoriesAxis.

4. The filer has reported a sub component of plan assets that does not represent a complete breakdown of the total. In these cases the element DefinedBenefitPlanPlanAssetsInvestmentWithinPlanAssetCategoryAmount should be used instead of the element DefinedBenefitPlanFairValueOfPlanAssets.

This rule aggregates the value of member components located on the axis at the highest level of aggregation to avoid double counting in the event that the company uses a hierarchy of members.

The properties of this DefinedBenefitPlanFairValueOfPlanAssets fact are:
Context: AR_I-CurrentYearEnd-1_us-gaap-2023RetirementPlanSponsorLocationAxis_us-gaap-2023ForeignPlanMember_us-gaap-2023RetirementPlanTypeAxis_us-gaap-2023PensionPlansDefinedBenefitMember
Unit: CHF. - cs-20231231.htm 1 - cs-20231231.htm 1</Log>
    <Log type="Warning">[EXG.rendering.tooManyDimensions] Presentation group http://www.credit-suisse.com/role/DisclosureLitigationDetails1 with 7 axes could have more than 1 billion cells.  Split up this presentation group and see EXG, Rendering, to see how to reduce the number of combinations by selecting fewer members for each axis. - cs-20231231.htm  - cs-20231231.htm </Log>
  </Logs>
  <InputFiles>
    <File doctype="20-F" isDefinitelyFs="true" isUsgaap="true" original="cs-20231231.htm">cs-20231231.htm</File>
    <File>cs-20231231.xsd</File>
    <File>cs-20231231_cal.xml</File>
    <File>cs-20231231_def.xml</File>
    <File>cs-20231231_lab.xml</File>
    <File>cs-20231231_pre.xml</File>
  </InputFiles>
  <SupplementalFiles>
    <File>x03iii_0017.gif</File>
    <File>x03iii_0020.gif</File>
    <File>x03iii_0021.gif</File>
    <File>x04iv_0001.gif</File>
    <File>x06_0001.gif</File>
    <File>x06_0002.gif</File>
    <File>x06_0003.gif</File>
    <File>xman_cover-back.jpg</File>
    <File>xman_cover-front.jpg</File>
  </SupplementalFiles>
  <BaseTaxonomies>
    <BaseTaxonomy items="2">http://fasb.org/srt/2023</BaseTaxonomy>
    <BaseTaxonomy items="6270">http://fasb.org/us-gaap/2023</BaseTaxonomy>
    <BaseTaxonomy items="48">http://xbrl.sec.gov/dei/2023</BaseTaxonomy>
  </BaseTaxonomies>
  <HasPresentationLinkbase>true</HasPresentationLinkbase>
  <HasCalculationLinkbase>true</HasCalculationLinkbase>
</FilingSummary>
