3.26.1 html 200 275 1 true 69 0 false 7 false false R1.htm 75000 - Document - Document and Entity Information Sheet http://erasca.com/20260331/taxonomy/role/Role_DocumentDocumentAndEntityInformation Document and Entity Information Cover 1 false false R2.htm 75010 - Statement - Condensed Consolidated Balance Sheets (Unaudited) Sheet http://erasca.com/20260331/taxonomy/role/Role_StatementCondensedConsolidatedBalanceSheetsUnaudited Condensed Consolidated Balance Sheets (Unaudited) Statements 2 false false R3.htm 75020 - Statement - Condensed Consolidated Balance Sheets (Unaudited) (Parenthetical) Sheet http://erasca.com/20260331/taxonomy/role/Role_StatementCondensedConsolidatedBalanceSheetsUnauditedParenthetical Condensed Consolidated Balance Sheets (Unaudited) (Parenthetical) Statements 3 false false R4.htm 75030 - Statement - Condensed Consolidated Statements of Operations and Comprehensive Loss (Unaudited) Sheet http://erasca.com/20260331/taxonomy/role/StatementCondensedConsolidatedStatementsOfOperationsAndComprehensiveLossUnaudited Condensed Consolidated Statements of Operations and Comprehensive Loss (Unaudited) Statements 4 false false R5.htm 75040 - Statement - Condensed Consolidated Statements of Stockholders' Equity (Unaudited) Sheet http://erasca.com/20260331/taxonomy/role/StatementCondensedConsolidatedStatementsOfStockholdersEquityUnaudited Condensed Consolidated Statements of Stockholders' Equity (Unaudited) Statements 5 false false R6.htm 75060 - Statement - Condensed Consolidated Statements of Cash Flows (Unaudited) Sheet http://erasca.com/20260331/taxonomy/role/Role_StatementCondensedConsolidatedStatementsOfCashFlowsUnaudited Condensed Consolidated Statements of Cash Flows (Unaudited) Statements 6 false false R7.htm 995410 - Disclosure - Pay vs Performance Disclosure Sheet http://xbrl.sec.gov/ecd/role/PvpDisclosure Pay vs Performance Disclosure Notes 7 false false R8.htm 995445 - Disclosure - Insider Trading Arrangements Sheet http://xbrl.sec.gov/ecd/role/InsiderTradingArrangements Insider Trading Arrangements Notes 8 false false R9.htm 995455 - Disclosure - Organization and Basis of Presentation Sheet http://erasca.com/20260331/taxonomy/role/Role_DisclosureOrganizationAndBasisOfPresentation Organization and Basis of Presentation Notes 9 false false R10.htm 995465 - Disclosure - Summary of Significant Accounting Policies Sheet http://erasca.com/20260331/taxonomy/role/Role_DisclosureSummaryOfSignificantAccountingPolicies Summary of Significant Accounting Policies Notes 10 false false R11.htm 995475 - Disclosure - Fair Value Measurements Sheet http://erasca.com/20260331/taxonomy/role/Role_DisclosureFairValueMeasurements Fair Value Measurements Notes 11 false false R12.htm 995485 - Disclosure - Marketable Securities Sheet http://erasca.com/20260331/taxonomy/role/DisclosureMarketableSecurities1 Marketable Securities Notes 12 false false R13.htm 995495 - Disclosure - Property and Equipment, Net Sheet http://erasca.com/20260331/taxonomy/role/Role_DisclosurePropertyAndEquipmentNet Property and Equipment, Net Notes 13 false false R14.htm 995505 - Disclosure - Accrued Expenses and Other Current Liabilities Sheet http://erasca.com/20260331/taxonomy/role/DisclosureAccruedExpensesAndOtherCurrentLiabilities1 Accrued Expenses and Other Current Liabilities Notes 14 false false R15.htm 995525 - Disclosure - License Agreements Sheet http://erasca.com/20260331/taxonomy/role/Role_DisclosureLicenseAgreements License Agreements Notes 15 false false R16.htm 995535 - Disclosure - Stockholders' Equity Sheet http://erasca.com/20260331/taxonomy/role/DisclosureStockholdersEquity Stockholders' Equity Notes 16 false false R17.htm 995545 - Disclosure - Stock-based Compensation Sheet http://erasca.com/20260331/taxonomy/role/Role_DisclosureStockBasedCompensation Stock-based Compensation Notes 17 false false R18.htm 995555 - Disclosure - Leases Sheet http://erasca.com/20260331/taxonomy/role/Role_DisclosureLeases Leases Notes 18 false false R19.htm 995565 - Disclosure - Commitments and Contingencies Sheet http://erasca.com/20260331/taxonomy/role/Role_DisclosureCommitmentsAndContingencies Commitments and Contingencies Notes 19 false false R20.htm 995575 - Disclosure - Income Taxes Sheet http://erasca.com/20260331/taxonomy/role/Role_DisclosureIncomeTaxes Income Taxes Notes 20 false false R21.htm 995585 - Disclosure - Net Loss Per Share Sheet http://erasca.com/20260331/taxonomy/role/Role_DisclosureNetLossPerShare Net Loss Per Share Notes 21 false false R22.htm 995605 - Disclosure - Segment Information Sheet http://erasca.com/20260331/taxonomy/role/DisclosureSegmentInformation Segment Information Notes 22 false false R23.htm 995615 - Disclosure - Summary of Significant Accounting Policies (Policies) Sheet http://erasca.com/20260331/taxonomy/role/Role_DisclosureSummaryOfSignificantAccountingPoliciesPolicies Summary of Significant Accounting Policies (Policies) Policies http://erasca.com/20260331/taxonomy/role/Role_DisclosureSummaryOfSignificantAccountingPolicies 23 false false R24.htm 995625 - Disclosure - Summary of Significant Accounting Policies (Tables) Sheet http://erasca.com/20260331/taxonomy/role/Role_DisclosureSummaryOfSignificantAccountingPoliciesTables Summary of Significant Accounting Policies (Tables) Tables http://erasca.com/20260331/taxonomy/role/Role_DisclosureSummaryOfSignificantAccountingPolicies 24 false false R25.htm 995635 - Disclosure - Fair Value Measurements (Tables) Sheet http://erasca.com/20260331/taxonomy/role/Role_DisclosureFairValueMeasurementsTables Fair Value Measurements (Tables) Tables http://erasca.com/20260331/taxonomy/role/Role_DisclosureFairValueMeasurements 25 false false R26.htm 995645 - Disclosure - Marketable Securities (Tables) Sheet http://erasca.com/20260331/taxonomy/role/DisclosureMarketableSecuritiesTables Marketable Securities (Tables) Tables http://erasca.com/20260331/taxonomy/role/DisclosureMarketableSecurities1 26 false false R27.htm 995655 - Disclosure - Property and Equipment, Net (Tables) Sheet http://erasca.com/20260331/taxonomy/role/Role_DisclosurePropertyAndEquipmentNetTables Property and Equipment, Net (Tables) Tables http://erasca.com/20260331/taxonomy/role/Role_DisclosurePropertyAndEquipmentNet 27 false false R28.htm 995665 - Disclosure - Accrued Expenses and Other Current Liabilities (Tables) Sheet http://erasca.com/20260331/taxonomy/role/DisclosureAccruedExpensesAndOtherCurrentLiabilitiesTables Accrued Expenses and Other Current Liabilities (Tables) Tables http://erasca.com/20260331/taxonomy/role/DisclosureAccruedExpensesAndOtherCurrentLiabilities1 28 false false R29.htm 995675 - Disclosure - Stockholders' Equity (Tables) Sheet http://erasca.com/20260331/taxonomy/role/DisclosureStockholdersEquityTables Stockholders' Equity (Tables) Tables http://erasca.com/20260331/taxonomy/role/DisclosureStockholdersEquity 29 false false R30.htm 995685 - Disclosure - Stock-based Compensation (Tables) Sheet http://erasca.com/20260331/taxonomy/role/Role_DisclosureStockBasedCompensationTables Stock-based Compensation (Tables) Tables http://erasca.com/20260331/taxonomy/role/Role_DisclosureStockBasedCompensation 30 false false R31.htm 995695 - Disclosure - Leases (Tables) Sheet http://erasca.com/20260331/taxonomy/role/Role_DisclosureLeasesTables Leases (Tables) Tables http://erasca.com/20260331/taxonomy/role/Role_DisclosureLeases 31 false false R32.htm 995705 - Disclosure - Net Loss Per Share (Tables) Sheet http://erasca.com/20260331/taxonomy/role/Role_DisclosureNetLossPerShareTables Net Loss Per Share (Tables) Tables http://erasca.com/20260331/taxonomy/role/Role_DisclosureNetLossPerShare 32 false false R33.htm 995715 - Disclosure - Organization and Basis of Presentation - Additional Information (Details) Sheet http://erasca.com/20260331/taxonomy/role/Role_DisclosureOrganizationAndBasisOfPresentationAdditionalInformationDetails Organization and Basis of Presentation - Additional Information (Details) Details 33 false false R34.htm 995725 - Disclosure - Summary of Significant Accounting Policies - Additional Information (Details) Sheet http://erasca.com/20260331/taxonomy/role/Role_DisclosureSummaryOfSignificantAccountingPoliciesAdditionalInformationDetails Summary of Significant Accounting Policies - Additional Information (Details) Details 34 false false R35.htm 995735 - Disclosure - Summary of Significant Accounting Policies - Reconciliation of Cash, Cash Equivalents and Restricted Cash (Details) Sheet http://erasca.com/20260331/taxonomy/role/Role_DisclosureSummaryOfSignificantAccountingPoliciesReconciliationOfCashCashEquivalentsAndRestrictedCashDetails Summary of Significant Accounting Policies - Reconciliation of Cash, Cash Equivalents and Restricted Cash (Details) Details 35 false false R36.htm 995745 - Disclosure - Fair Value Measurements - Summary of Financial Assets Measured at Fair Value on Recurring Basis (Details) Sheet http://erasca.com/20260331/taxonomy/role/DisclosureFairValueMeasurementsSummaryOfFinancialAssetsMeasuredAtFairValueOnRecurringBasisDetails Fair Value Measurements - Summary of Financial Assets Measured at Fair Value on Recurring Basis (Details) Details 36 false false R37.htm 995755 - Disclosure - Fair Value Measurements - Additional Information (Details) Sheet http://erasca.com/20260331/taxonomy/role/Role_DisclosureFairValueMeasurementsAdditionalInformationDetails Fair Value Measurements - Additional Information (Details) Details 37 false false R38.htm 995765 - Disclosure - Marketable Securities - Summary of Marketable Securities Accounted for Available-for-Sale-Securities (Details) Sheet http://erasca.com/20260331/taxonomy/role/DisclosureMarketableSecuritiesSummaryOfMarketableSecuritiesAccountedForAvailableforsalesecuritiesDetails Marketable Securities - Summary of Marketable Securities Accounted for Available-for-Sale-Securities (Details) Details 38 false false R39.htm 995775 - Disclosure - Marketable Securities - Summary of Fair Values and Gross Unrealized Losses for Available-for-sale Securities (Details) Sheet http://erasca.com/20260331/taxonomy/role/DisclosureMarketableSecuritiesSummaryOfFairValuesAndGrossUnrealizedLossesForAvailableforsaleSecuritiesDetails Marketable Securities - Summary of Fair Values and Gross Unrealized Losses for Available-for-sale Securities (Details) Details 39 false false R40.htm 995785 - Disclosure - Marketable Securities - Additional Information (Details) Sheet http://erasca.com/20260331/taxonomy/role/DisclosureMarketableSecuritiesAdditionalInformationDetails Marketable Securities - Additional Information (Details) Details 40 false false R41.htm 995795 - Disclosure - Property and Equipment, Net - Schedule of Property and Equipment, Net (Details) Sheet http://erasca.com/20260331/taxonomy/role/Role_DisclosurePropertyAndEquipmentNetScheduleOfPropertyAndEquipmentNetDetails Property and Equipment, Net - Schedule of Property and Equipment, Net (Details) Details 41 false false R42.htm 995805 - Disclosure - Property and Equipment, Net - Additional Information (Details) Sheet http://erasca.com/20260331/taxonomy/role/Role_DisclosurePropertyAndEquipmentNetAdditionalInformationDetails Property and Equipment, Net - Additional Information (Details) Details 42 false false R43.htm 995815 - Disclosure - Accrued Expenses and Other Current Liabilities - Schedule of Accrued Expenses and Other Current Liabilities (Details) Sheet http://erasca.com/20260331/taxonomy/role/Role_DisclosureAccruedExpensesAndOtherCurrentLiabilitiesScheduleOfAccruedExpensesAndOtherCurrentLiabilitiesDetails Accrued Expenses and Other Current Liabilities - Schedule of Accrued Expenses and Other Current Liabilities (Details) Details 43 false false R44.htm 995825 - Disclosure - Asset Acquisitions - Additional Information (Details) Sheet http://erasca.com/20260331/taxonomy/role/Role_DisclosureAssetAcquisitionsAdditionalInformationDetails Asset Acquisitions - Additional Information (Details) Details 44 false false R45.htm 995835 - Disclosure - License Agreements - Additional Information (Details) Sheet http://erasca.com/20260331/taxonomy/role/Role_DisclosureLicenseAgreementsAdditionalInformationDetails License Agreements - Additional Information (Details) Details 45 false false R46.htm 995845 - Disclosure - Stockholders' Equity - Additional Information (Details) Sheet http://erasca.com/20260331/taxonomy/role/DisclosureStockholdersEquityAdditionalInformationDetails Stockholders' Equity - Additional Information (Details) Details 46 false false R47.htm 995855 - Disclosure - Stockholders' Equity - Summary of Common Stock Reserved for Future Issuance (Details) Sheet http://erasca.com/20260331/taxonomy/role/DisclosureStockholdersEquitySummaryOfCommonStockReservedForFutureIssuanceDetails Stockholders' Equity - Summary of Common Stock Reserved for Future Issuance (Details) Details 47 false false R48.htm 995865 - Disclosure - Stock-based Compensation - Additional Information (Details) Sheet http://erasca.com/20260331/taxonomy/role/Role_DisclosureStockBasedCompensationAdditionalInformationDetails Stock-based Compensation - Additional Information (Details) Details 48 false false R49.htm 995875 - Disclosure - Stock-based Compensation - Summary of Stock Option Activity (Details) Sheet http://erasca.com/20260331/taxonomy/role/Role_DisclosureStockBasedCompensationSummaryOfStockOptionActivityDetails Stock-based Compensation - Summary of Stock Option Activity (Details) Details 49 false false R50.htm 995885 - Disclosure - Stock-based Compensation - Assumptions used to Determine Fair Value of Stock Option Grants (Details) Sheet http://erasca.com/20260331/taxonomy/role/DisclosureStockbasedCompensationAssumptionsUsedToDetermineFairValueOfStockOptionGrantsDetails Stock-based Compensation - Assumptions used to Determine Fair Value of Stock Option Grants (Details) Details 50 false false R51.htm 995905 - Disclosure - Stock-based Compensation - Schedule of Stock-based Compensation Expense (Details) Sheet http://erasca.com/20260331/taxonomy/role/DisclosureStockbasedCompensationScheduleOfStockbasedCompensationExpenseDetails Stock-based Compensation - Schedule of Stock-based Compensation Expense (Details) Details 51 false false R52.htm 995915 - Disclosure - Leases - Additional Information (Details) Sheet http://erasca.com/20260331/taxonomy/role/Role_DisclosureLeasesAdditionalInformationDetails Leases - Additional Information (Details) Details 52 false false R53.htm 995925 - Disclosure - Leases - Schedule of Lease costs (Details) Sheet http://erasca.com/20260331/taxonomy/role/DisclosureLeasesScheduleOfLeaseCostsDetails Leases - Schedule of Lease costs (Details) Details 53 false false R54.htm 995935 - Disclosure - Leases - Schedule of Future Minimum Lease Payments under Operating Leases (Details) Sheet http://erasca.com/20260331/taxonomy/role/DisclosureLeasesScheduleOfFutureMinimumLeasePaymentsUnderOperatingLeasesDetails Leases - Schedule of Future Minimum Lease Payments under Operating Leases (Details) Details 54 false false R55.htm 995975 - Disclosure - Income Taxes - Additional Information (Details) Sheet http://erasca.com/20260331/taxonomy/role/Role_DisclosureIncomeTaxesAdditionalInformationDetails Income Taxes - Additional Information (Details) Details 55 false false R56.htm 995985 - Disclosure - Net Loss Per Share - Summary of Computation of Basic and Diluted Net Loss Per Share (Details) Sheet http://erasca.com/20260331/taxonomy/role/DisclosureNetLossPerShareSummaryOfComputationOfBasicAndDilutedNetLossPerShareDetails Net Loss Per Share - Summary of Computation of Basic and Diluted Net Loss Per Share (Details) Details 56 false false R57.htm 995995 - Disclosure - Net Loss Per Share - Anti-dilutive Securities Excluded from Calculation of Diluted Net Loss Per Share (Details) Sheet http://erasca.com/20260331/taxonomy/role/DisclosureNetLossPerShareAntidilutiveSecuritiesExcludedFromCalculationOfDilutedNetLossPerShareDetails Net Loss Per Share - Anti-dilutive Securities Excluded from Calculation of Diluted Net Loss Per Share (Details) Details 57 false false R58.htm 996005 - Disclosure - Segment Information - Additional Information (Details) Sheet http://erasca.com/20260331/taxonomy/role/DisclosureSegmentInformationAdditionalInformationDetails Segment Information - Additional Information (Details) Details 58 false false All Reports Book All Reports eras-20260331.htm eras-20260331.xsd img201854340_0.jpg img201854340_1.jpg img201854340_2.jpg img201854340_3.jpg http://fasb.org/us-gaap/2025 http://xbrl.sec.gov/dei/2025 http://xbrl.sec.gov/ecd/2025 false false