<?xml version='1.0' encoding='utf-8'?>
<FilingSummary>
  <Version>3.23.1</Version>
  <ProcessingTime/>
  <ReportFormat>html</ReportFormat>
  <ContextCount>157</ContextCount>
  <ElementCount>271</ElementCount>
  <EntityCount>1</EntityCount>
  <FootnotesReported>false</FootnotesReported>
  <SegmentCount>45</SegmentCount>
  <ScenarioCount>0</ScenarioCount>
  <TuplesReported>false</TuplesReported>
  <UnitCount>5</UnitCount>
  <MyReports>
    <Report instance="crnx-20230331.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R1.htm</HtmlFileName>
      <LongName>100000 - Document - Document and Entity Information</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.crinetics.com/20230331/taxonomy/role/Role_DocumentDocumentAndEntityInformation</Role>
      <ShortName>Document and Entity Information</ShortName>
      <MenuCategory>Cover</MenuCategory>
      <Position>1</Position>
    </Report>
    <Report instance="crnx-20230331.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R2.htm</HtmlFileName>
      <LongName>100010 - Statement - Condensed Consolidated Balance Sheets</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.crinetics.com/20230331/taxonomy/role/Role_StatementCondensedConsolidatedBalanceSheets</Role>
      <ShortName>Condensed Consolidated Balance Sheets</ShortName>
      <MenuCategory>Statements</MenuCategory>
      <Position>2</Position>
    </Report>
    <Report instance="crnx-20230331.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R3.htm</HtmlFileName>
      <LongName>100020 - Statement - Condensed Consolidated Balance Sheets (Parenthetical)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.crinetics.com/20230331/taxonomy/role/Role_StatementCondensedConsolidatedBalanceSheetsParenthetical</Role>
      <ShortName>Condensed Consolidated Balance Sheets (Parenthetical)</ShortName>
      <MenuCategory>Statements</MenuCategory>
      <Position>3</Position>
    </Report>
    <Report instance="crnx-20230331.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R4.htm</HtmlFileName>
      <LongName>100030 - Statement - Condensed Consolidated Statements of Operations and Comprehensive Loss (Unaudited)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.crinetics.com/20230331/taxonomy/role/Role_StatementCondensedConsolidatedStatementsOfOperationsAndComprehensiveLossUnaudited</Role>
      <ShortName>Condensed Consolidated Statements of Operations and Comprehensive Loss (Unaudited)</ShortName>
      <MenuCategory>Statements</MenuCategory>
      <Position>4</Position>
    </Report>
    <Report instance="crnx-20230331.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R5.htm</HtmlFileName>
      <LongName>100040 - Statement - Condensed Consolidated Statements of Stockholders' Equity (Unaudited)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.crinetics.com/20230331/taxonomy/role/Role_StatementCondensedConsolidatedStatementsOfStockholdersEquityUnaudited</Role>
      <ShortName>Condensed Consolidated Statements of Stockholders' Equity (Unaudited)</ShortName>
      <MenuCategory>Statements</MenuCategory>
      <Position>5</Position>
    </Report>
    <Report instance="crnx-20230331.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R6.htm</HtmlFileName>
      <LongName>100060 - Statement - Condensed Consolidated Statements of Cash Flows (Unaudited)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.crinetics.com/20230331/taxonomy/role/Role_StatementCondensedConsolidatedStatementsOfCashFlowsUnaudited</Role>
      <ShortName>Condensed Consolidated Statements of Cash Flows (Unaudited)</ShortName>
      <MenuCategory>Statements</MenuCategory>
      <Position>6</Position>
    </Report>
    <Report instance="crnx-20230331.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R7.htm</HtmlFileName>
      <LongName>100080 - Disclosure - Organization and Basis of Presentation</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.crinetics.com/20230331/taxonomy/role/Role_DisclosureOrganizationAndBasisOfPresentation</Role>
      <ShortName>Organization and Basis of Presentation</ShortName>
      <MenuCategory>Notes</MenuCategory>
      <Position>7</Position>
    </Report>
    <Report instance="crnx-20230331.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R8.htm</HtmlFileName>
      <LongName>100090 - Disclosure - Summary of Significant Accounting Policies</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.crinetics.com/20230331/taxonomy/role/Role_DisclosureSummaryOfSignificantAccountingPolicies</Role>
      <ShortName>Summary of Significant Accounting Policies</ShortName>
      <MenuCategory>Notes</MenuCategory>
      <Position>8</Position>
    </Report>
    <Report instance="crnx-20230331.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R9.htm</HtmlFileName>
      <LongName>100100 - Disclosure - Investment Securities</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.crinetics.com/20230331/taxonomy/role/Role_DisclosureInvestmentSecurities</Role>
      <ShortName>Investment Securities</ShortName>
      <MenuCategory>Notes</MenuCategory>
      <Position>9</Position>
    </Report>
    <Report instance="crnx-20230331.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R10.htm</HtmlFileName>
      <LongName>100110 - Disclosure - Fair Value Measurements</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.crinetics.com/20230331/taxonomy/role/Role_DisclosureFairValueMeasurements</Role>
      <ShortName>Fair Value Measurements</ShortName>
      <MenuCategory>Notes</MenuCategory>
      <Position>10</Position>
    </Report>
    <Report instance="crnx-20230331.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R11.htm</HtmlFileName>
      <LongName>100120 - Disclosure - Balance Sheet Details</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.crinetics.com/20230331/taxonomy/role/Role_DisclosureBalanceSheetDetails</Role>
      <ShortName>Balance Sheet Details</ShortName>
      <MenuCategory>Notes</MenuCategory>
      <Position>11</Position>
    </Report>
    <Report instance="crnx-20230331.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R12.htm</HtmlFileName>
      <LongName>100130 - Disclosure - Operating Lease</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.crinetics.com/20230331/taxonomy/role/Role_DisclosureOperatingLease</Role>
      <ShortName>Operating Lease</ShortName>
      <MenuCategory>Notes</MenuCategory>
      <Position>12</Position>
    </Report>
    <Report instance="crnx-20230331.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R13.htm</HtmlFileName>
      <LongName>100140 - Disclosure - Commitments and Contingencies</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.crinetics.com/20230331/taxonomy/role/Role_DisclosureCommitmentsAndContingencies</Role>
      <ShortName>Commitments and Contingencies</ShortName>
      <MenuCategory>Notes</MenuCategory>
      <Position>13</Position>
    </Report>
    <Report instance="crnx-20230331.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R14.htm</HtmlFileName>
      <LongName>100150 - Disclosure - Stockholder's Equity</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.crinetics.com/20230331/taxonomy/role/Role_DisclosureStockholderSEquity</Role>
      <ShortName>Stockholder's Equity</ShortName>
      <MenuCategory>Notes</MenuCategory>
      <Position>14</Position>
    </Report>
    <Report instance="crnx-20230331.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R15.htm</HtmlFileName>
      <LongName>100160 - Disclosure - Revenue Recognition</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.crinetics.com/20230331/taxonomy/role/DisclosureRevenueRecognition</Role>
      <ShortName>Revenue Recognition</ShortName>
      <MenuCategory>Notes</MenuCategory>
      <Position>15</Position>
    </Report>
    <Report instance="crnx-20230331.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R16.htm</HtmlFileName>
      <LongName>100170 - Disclosure - Equity Incentive Plans</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.crinetics.com/20230331/taxonomy/role/Role_DisclosureEquityIncentivePlans</Role>
      <ShortName>Equity Incentive Plans</ShortName>
      <MenuCategory>Notes</MenuCategory>
      <Position>16</Position>
    </Report>
    <Report instance="crnx-20230331.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R17.htm</HtmlFileName>
      <LongName>100180 - Disclosure - Summary of Significant Accounting Policies (Policies)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.crinetics.com/20230331/taxonomy/role/Role_DisclosureSummaryOfSignificantAccountingPoliciesPolicies</Role>
      <ShortName>Summary of Significant Accounting Policies (Policies)</ShortName>
      <MenuCategory>Policies</MenuCategory>
      <ParentRole>http://www.crinetics.com/20230331/taxonomy/role/Role_DisclosureSummaryOfSignificantAccountingPolicies</ParentRole>
      <Position>17</Position>
    </Report>
    <Report instance="crnx-20230331.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R18.htm</HtmlFileName>
      <LongName>100190 - Disclosure - Summary of Significant Accounting Policies (Table)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.crinetics.com/20230331/taxonomy/role/Role_DisclosureSummaryOfSignificantAccountingPoliciesTable</Role>
      <ShortName>Summary of Significant Accounting Policies (Table)</ShortName>
      <MenuCategory>Tables</MenuCategory>
      <ParentRole>http://www.crinetics.com/20230331/taxonomy/role/Role_DisclosureSummaryOfSignificantAccountingPolicies</ParentRole>
      <Position>18</Position>
    </Report>
    <Report instance="crnx-20230331.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R19.htm</HtmlFileName>
      <LongName>100200 - Disclosure - Investment Securities (Tables)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.crinetics.com/20230331/taxonomy/role/Role_DisclosureInvestmentSecuritiesTables</Role>
      <ShortName>Investment Securities (Tables)</ShortName>
      <MenuCategory>Tables</MenuCategory>
      <ParentRole>http://www.crinetics.com/20230331/taxonomy/role/Role_DisclosureInvestmentSecurities</ParentRole>
      <Position>19</Position>
    </Report>
    <Report instance="crnx-20230331.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R20.htm</HtmlFileName>
      <LongName>100210 - Disclosure - Fair Value Measurements (Tables)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.crinetics.com/20230331/taxonomy/role/Role_DisclosureFairValueMeasurementsTables</Role>
      <ShortName>Fair Value Measurements (Tables)</ShortName>
      <MenuCategory>Tables</MenuCategory>
      <ParentRole>http://www.crinetics.com/20230331/taxonomy/role/Role_DisclosureFairValueMeasurements</ParentRole>
      <Position>20</Position>
    </Report>
    <Report instance="crnx-20230331.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R21.htm</HtmlFileName>
      <LongName>100220 - Disclosure - Balance Sheet Details (Tables)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.crinetics.com/20230331/taxonomy/role/Role_DisclosureBalanceSheetDetailsTables</Role>
      <ShortName>Balance Sheet Details (Tables)</ShortName>
      <MenuCategory>Tables</MenuCategory>
      <ParentRole>http://www.crinetics.com/20230331/taxonomy/role/Role_DisclosureBalanceSheetDetails</ParentRole>
      <Position>21</Position>
    </Report>
    <Report instance="crnx-20230331.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R22.htm</HtmlFileName>
      <LongName>100230 - Disclosure - Operating Lease (Tables)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.crinetics.com/20230331/taxonomy/role/Role_DisclosureOperatingLeaseTables</Role>
      <ShortName>Operating Lease (Tables)</ShortName>
      <MenuCategory>Tables</MenuCategory>
      <ParentRole>http://www.crinetics.com/20230331/taxonomy/role/Role_DisclosureOperatingLease</ParentRole>
      <Position>22</Position>
    </Report>
    <Report instance="crnx-20230331.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R23.htm</HtmlFileName>
      <LongName>100240 - Disclosure - Revenue Recognition (Tables)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.crinetics.com/20230331/taxonomy/role/DisclosureRevenueRecognitionTables</Role>
      <ShortName>Revenue Recognition (Tables)</ShortName>
      <MenuCategory>Tables</MenuCategory>
      <ParentRole>http://www.crinetics.com/20230331/taxonomy/role/DisclosureRevenueRecognition</ParentRole>
      <Position>23</Position>
    </Report>
    <Report instance="crnx-20230331.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R24.htm</HtmlFileName>
      <LongName>100250 - Disclosure - Equity Incentive Plans (Tables)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.crinetics.com/20230331/taxonomy/role/Role_DisclosureEquityIncentivePlansTables</Role>
      <ShortName>Equity Incentive Plans (Tables)</ShortName>
      <MenuCategory>Tables</MenuCategory>
      <ParentRole>http://www.crinetics.com/20230331/taxonomy/role/Role_DisclosureEquityIncentivePlans</ParentRole>
      <Position>24</Position>
    </Report>
    <Report instance="crnx-20230331.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R25.htm</HtmlFileName>
      <LongName>100260 - Disclosure - Organization and Basis of Presentation - Additional Information (Details)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.crinetics.com/20230331/taxonomy/role/Role_DisclosureOrganizationAndBasisOfPresentationAdditionalInformationDetails</Role>
      <ShortName>Organization and Basis of Presentation - Additional Information (Details)</ShortName>
      <MenuCategory>Details</MenuCategory>
      <Position>25</Position>
    </Report>
    <Report instance="crnx-20230331.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R26.htm</HtmlFileName>
      <LongName>100270 - Disclosure - Summary of Significant Accounting Policies - Additional Information (Details)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.crinetics.com/20230331/taxonomy/role/Role_DisclosureSummaryOfSignificantAccountingPoliciesAdditionalInformationDetails</Role>
      <ShortName>Summary of Significant Accounting Policies - Additional Information (Details)</ShortName>
      <MenuCategory>Details</MenuCategory>
      <Position>26</Position>
    </Report>
    <Report instance="crnx-20230331.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R27.htm</HtmlFileName>
      <LongName>100280 - Disclosure - Summary of Significant Accounting Policies - Schedule of Potentially Dilutive Securities not Included in Calculation of Diluted Net Loss Per Share (Details)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.crinetics.com/20230331/taxonomy/role/Role_DisclosureSummaryOfSignificantAccountingPoliciesScheduleOfPotentiallyDilutiveSecuritiesNotIncludedInCalculationOfDilutedNetLossPerShareDetails</Role>
      <ShortName>Summary of Significant Accounting Policies - Schedule of Potentially Dilutive Securities not Included in Calculation of Diluted Net Loss Per Share (Details)</ShortName>
      <MenuCategory>Details</MenuCategory>
      <Position>27</Position>
    </Report>
    <Report instance="crnx-20230331.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R28.htm</HtmlFileName>
      <LongName>100290 - Disclosure - Investment Securities - Summary of Available-For-Sale Investment Securities Held by the Company (Details)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.crinetics.com/20230331/taxonomy/role/Role_DisclosureInvestmentSecuritiesSummaryOfAvailableForSaleInvestmentSecuritiesHeldByCompanyDetails</Role>
      <ShortName>Investment Securities - Summary of Available-For-Sale Investment Securities Held by the Company (Details)</ShortName>
      <MenuCategory>Details</MenuCategory>
      <Position>28</Position>
    </Report>
    <Report instance="crnx-20230331.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R29.htm</HtmlFileName>
      <LongName>100300 - Disclosure - Investment Securities - Summary of Available-For-Sale Investment Securities by Contractual Maturity (Details)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.crinetics.com/20230331/taxonomy/role/DisclosureInvestmentSecuritiesSummaryOfAvailableforsaleInvestmentSecuritiesByContractualMaturityDetails</Role>
      <ShortName>Investment Securities - Summary of Available-For-Sale Investment Securities by Contractual Maturity (Details)</ShortName>
      <MenuCategory>Details</MenuCategory>
      <Position>29</Position>
    </Report>
    <Report instance="crnx-20230331.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R30.htm</HtmlFileName>
      <LongName>100310 - Disclosure - Investment Securities - Summary of Available-For-Sale Securities Investment (Details)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.crinetics.com/20230331/taxonomy/role/DisclosureInvestmentSecuritiesSummaryOfAvailableforsaleSecuritiesInvestmentDetails</Role>
      <ShortName>Investment Securities - Summary of Available-For-Sale Securities Investment (Details)</ShortName>
      <MenuCategory>Details</MenuCategory>
      <Position>30</Position>
    </Report>
    <Report instance="crnx-20230331.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R31.htm</HtmlFileName>
      <LongName>100330 - Disclosure - Fair Value Measurements - Schedule of Financial Assets Measured at Fair Value on Recurring Basis (Details)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.crinetics.com/20230331/taxonomy/role/Role_DisclosureFairValueMeasurementsScheduleOfFinancialAssetsMeasuredAtFairValueOnRecurringBasisDetails</Role>
      <ShortName>Fair Value Measurements - Schedule of Financial Assets Measured at Fair Value on Recurring Basis (Details)</ShortName>
      <MenuCategory>Details</MenuCategory>
      <Position>31</Position>
    </Report>
    <Report instance="crnx-20230331.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R32.htm</HtmlFileName>
      <LongName>100340 - Disclosure - Fair Value Measurements - Additional Information (Details)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.crinetics.com/20230331/taxonomy/role/Role_DisclosureFairValueMeasurementsAdditionalInformationDetails</Role>
      <ShortName>Fair Value Measurements - Additional Information (Details)</ShortName>
      <MenuCategory>Details</MenuCategory>
      <Position>32</Position>
    </Report>
    <Report instance="crnx-20230331.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R33.htm</HtmlFileName>
      <LongName>100350 - Disclosure - Balance Sheet Details - Components of Prepaid Expenses and Other Current Assets (Details)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.crinetics.com/20230331/taxonomy/role/Role_DisclosureBalanceSheetDetailsComponentsOfPrepaidExpensesAndOtherCurrentAssetsDetails</Role>
      <ShortName>Balance Sheet Details - Components of Prepaid Expenses and Other Current Assets (Details)</ShortName>
      <MenuCategory>Details</MenuCategory>
      <Position>33</Position>
    </Report>
    <Report instance="crnx-20230331.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R34.htm</HtmlFileName>
      <LongName>100360 - Disclosure - Balance Sheet Details - Components of Property and Equipment, Net (Details)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.crinetics.com/20230331/taxonomy/role/Role_DisclosureBalanceSheetDetailsComponentsOfPropertyAndEquipmentNetDetails</Role>
      <ShortName>Balance Sheet Details - Components of Property and Equipment, Net (Details)</ShortName>
      <MenuCategory>Details</MenuCategory>
      <Position>34</Position>
    </Report>
    <Report instance="crnx-20230331.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R35.htm</HtmlFileName>
      <LongName>100370 - Disclosure - Balance Sheet Details - Schedule of Accounts Payable and Accrued Expenses (Details)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.crinetics.com/20230331/taxonomy/role/DisclosureBalanceSheetDetailsScheduleOfAccountsPayableAndAccruedExpensesDetails</Role>
      <ShortName>Balance Sheet Details - Schedule of Accounts Payable and Accrued Expenses (Details)</ShortName>
      <MenuCategory>Details</MenuCategory>
      <Position>35</Position>
    </Report>
    <Report instance="crnx-20230331.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R36.htm</HtmlFileName>
      <LongName>100380 - Disclosure - Operating Lease - Additional Information (Details)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.crinetics.com/20230331/taxonomy/role/Role_DisclosureOperatingLeaseAdditionalInformationDetails</Role>
      <ShortName>Operating Lease - Additional Information (Details)</ShortName>
      <MenuCategory>Details</MenuCategory>
      <Position>36</Position>
    </Report>
    <Report instance="crnx-20230331.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R37.htm</HtmlFileName>
      <LongName>100390 - Disclosure - Operating Lease - Schedule of Future Minimum Payments Under Non-cancellable Operating Leases (Details)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.crinetics.com/20230331/taxonomy/role/Role_DisclosureOperatingLeaseScheduleOfFutureMinimumPaymentsUnderNonCancellableOperatingLeasesDetails</Role>
      <ShortName>Operating Lease - Schedule of Future Minimum Payments Under Non-cancellable Operating Leases (Details)</ShortName>
      <MenuCategory>Details</MenuCategory>
      <Position>37</Position>
    </Report>
    <Report instance="crnx-20230331.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R38.htm</HtmlFileName>
      <LongName>100400 - Disclosure - Revenue Recognition - Schedule of Deferred Revenue Components (Details)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.crinetics.com/20230331/taxonomy/role/DisclosureRevenueRecognitionScheduleOfDeferredRevenueComponentsDetails</Role>
      <ShortName>Revenue Recognition - Schedule of Deferred Revenue Components (Details)</ShortName>
      <MenuCategory>Details</MenuCategory>
      <Position>38</Position>
    </Report>
    <Report instance="crnx-20230331.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R39.htm</HtmlFileName>
      <LongName>100410 - Disclosure - Revenue Recognition (Additional Information) (Details)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.crinetics.com/20230331/taxonomy/role/DisclosureRevenueRecognitionAdditionalInformationDetails</Role>
      <ShortName>Revenue Recognition (Additional Information) (Details)</ShortName>
      <MenuCategory>Details</MenuCategory>
      <ParentRole>http://www.crinetics.com/20230331/taxonomy/role/DisclosureRevenueRecognitionTables</ParentRole>
      <Position>39</Position>
    </Report>
    <Report instance="crnx-20230331.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R40.htm</HtmlFileName>
      <LongName>100420 - Disclosure - Stockholder's Equity - Additional Information (Details)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.crinetics.com/20230331/taxonomy/role/Role_DisclosureStockholderSEquityAdditionalInformationDetails</Role>
      <ShortName>Stockholder's Equity - Additional Information (Details)</ShortName>
      <MenuCategory>Details</MenuCategory>
      <Position>40</Position>
    </Report>
    <Report instance="crnx-20230331.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R41.htm</HtmlFileName>
      <LongName>100430 - Disclosure - Equity Incentive Plans - Additional Information (Details)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.crinetics.com/20230331/taxonomy/role/Role_DisclosureEquityIncentivePlansAdditionalInformationDetails</Role>
      <ShortName>Equity Incentive Plans - Additional Information (Details)</ShortName>
      <MenuCategory>Details</MenuCategory>
      <Position>41</Position>
    </Report>
    <Report instance="crnx-20230331.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R42.htm</HtmlFileName>
      <LongName>100440 - Disclosure - Equity Incentive Plans - Summary of Activity Under Stock Option activity (Details)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.crinetics.com/20230331/taxonomy/role/DisclosureEquityIncentivePlansSummaryOfActivityUnderStockOptionActivityDetails</Role>
      <ShortName>Equity Incentive Plans - Summary of Activity Under Stock Option activity (Details)</ShortName>
      <MenuCategory>Details</MenuCategory>
      <Position>42</Position>
    </Report>
    <Report instance="crnx-20230331.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R43.htm</HtmlFileName>
      <LongName>100450 - Disclosure - Equity Incentive Plans - Weighted Average Assumptions Used to Estimate Fair Value of Stock Options Granted to Employees (Details)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.crinetics.com/20230331/taxonomy/role/Role_DisclosureEquityIncentivePlansWeightedAverageAssumptionsUsedToEstimateFairValueOfStockOptionsGrantedToEmployeesDetails</Role>
      <ShortName>Equity Incentive Plans - Weighted Average Assumptions Used to Estimate Fair Value of Stock Options Granted to Employees (Details)</ShortName>
      <MenuCategory>Details</MenuCategory>
      <Position>43</Position>
    </Report>
    <Report instance="crnx-20230331.htm">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R44.htm</HtmlFileName>
      <LongName>100460 - Disclosure - Equity Incentive Plans - Stock-based Compensation Expense Recognized (Details)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.crinetics.com/20230331/taxonomy/role/Role_DisclosureEquityIncentivePlansStockBasedCompensationExpenseRecognizedDetails</Role>
      <ShortName>Equity Incentive Plans - Stock-based Compensation Expense Recognized (Details)</ShortName>
      <MenuCategory>Details</MenuCategory>
      <Position>44</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">[dq-0542-Deprecated-Concept] Concept DueFromAffiliateCurrent in us-gaap/2022 used in 4 facts was deprecated in us-gaap/2023 as of 2023 and should not be used. crnx-20230331.htm 1784, 3153, 3157</Log>
  </Logs>
  <InputFiles>
    <File doctype="10-Q" original="crnx-20230331.htm">crnx-20230331.htm</File>
    <File>crnx-20230331.xsd</File>
    <File>crnx-20230331_cal.xml</File>
    <File>crnx-20230331_def.xml</File>
    <File>crnx-20230331_lab.xml</File>
    <File>crnx-20230331_pre.xml</File>
    <File>crnx-ex10_2.htm</File>
    <File>crnx-ex31_1.htm</File>
    <File>crnx-ex31_2.htm</File>
    <File>crnx-ex32_1.htm</File>
  </InputFiles>
  <SupplementalFiles/>
  <BaseTaxonomies>
    <BaseTaxonomy items="499">http://fasb.org/us-gaap/2022</BaseTaxonomy>
    <BaseTaxonomy items="31">http://xbrl.sec.gov/dei/2022</BaseTaxonomy>
  </BaseTaxonomies>
  <HasPresentationLinkbase>true</HasPresentationLinkbase>
  <HasCalculationLinkbase>true</HasCalculationLinkbase>
</FilingSummary>
