3.8.0.1 html 216 373 1 false 74 0 false 6 false false R1.htm 100000 - Document - Document and Entity Information Sheet http://www.ultragenyx.com/20171231/taxonomy/role/DocumentDocumentAndEntityInformation Document and Entity Information Cover 1 false false R2.htm 100010 - Statement - CONSOLIDATED BALANCE SHEETS Sheet http://www.ultragenyx.com/20171231/taxonomy/role/StatementCONSOLIDATEDBALANCESHEETS CONSOLIDATED BALANCE SHEETS Statements 2 false false R3.htm 100020 - Statement - CONSOLIDATED BALANCE SHEETS (Parenthetical) Sheet http://www.ultragenyx.com/20171231/taxonomy/role/StatementCONSOLIDATEDBALANCESHEETSParenthetical CONSOLIDATED BALANCE SHEETS (Parenthetical) Statements 3 false false R4.htm 100030 - Statement - CONSOLIDATED STATEMENTS OF OPERATIONS Sheet http://www.ultragenyx.com/20171231/taxonomy/role/StatementCONSOLIDATEDSTATEMENTSOFOPERATIONS CONSOLIDATED STATEMENTS OF OPERATIONS Statements 4 false false R5.htm 100040 - Statement - CONSOLIDATED STATEMENTS OF COMPREHENSIVE LOSS Sheet http://www.ultragenyx.com/20171231/taxonomy/role/StatementCONSOLIDATEDSTATEMENTSOFCOMPREHENSIVELOSS CONSOLIDATED STATEMENTS OF COMPREHENSIVE LOSS Statements 5 false false R6.htm 100050 - Statement - CONSOLIDATED STATEMENTS OF SHAREHOLDERS' EQUITY Sheet http://www.ultragenyx.com/20171231/taxonomy/role/StatementCONSOLIDATEDSTATEMENTSOFSHAREHOLDERSEQUITY CONSOLIDATED STATEMENTS OF SHAREHOLDERS' EQUITY Statements 6 false false R7.htm 100060 - Statement - CONSOLIDATED STATEMENTS OF CASH FLOWS Sheet http://www.ultragenyx.com/20171231/taxonomy/role/StatementCONSOLIDATEDSTATEMENTSOFCASHFLOWS CONSOLIDATED STATEMENTS OF CASH FLOWS Statements 7 false false R8.htm 100070 - Disclosure - Organization and Basis of Presentation Sheet http://www.ultragenyx.com/20171231/taxonomy/role/DisclosureOrganizationAndBasisOfPresentation Organization and Basis of Presentation Notes 8 false false R9.htm 100080 - Disclosure - Summary of Significant Accounting Policies Sheet http://www.ultragenyx.com/20171231/taxonomy/role/DisclosureSummaryOfSignificantAccountingPolicies Summary of Significant Accounting Policies Notes 9 false false R10.htm 100090 - Disclosure - Acquisition Sheet http://www.ultragenyx.com/20171231/taxonomy/role/DisclosureAcquisition Acquisition Notes 10 false false R11.htm 100100 - Disclosure - Fair Value Measurements Sheet http://www.ultragenyx.com/20171231/taxonomy/role/DisclosureFairValueMeasurements Fair Value Measurements Notes 11 false false R12.htm 100110 - Disclosure - Balance Sheet Components Sheet http://www.ultragenyx.com/20171231/taxonomy/role/DisclosureBalanceSheetComponents Balance Sheet Components Notes 12 false false R13.htm 100120 - Disclosure - Intangible Assets, Net Sheet http://www.ultragenyx.com/20171231/taxonomy/role/DisclosureIntangibleAssetsNet Intangible Assets, Net Notes 13 false false R14.htm 100130 - Disclosure - License and Research Agreements Sheet http://www.ultragenyx.com/20171231/taxonomy/role/DisclosureLicenseAndResearchAgreements License and Research Agreements Notes 14 false false R15.htm 100140 - Disclosure - Equity Sheet http://www.ultragenyx.com/20171231/taxonomy/role/DisclosureEquity Equity Notes 15 false false R16.htm 100150 - Disclosure - Stock-Based Awards Sheet http://www.ultragenyx.com/20171231/taxonomy/role/DisclosureStockBasedAwards Stock-Based Awards Notes 16 false false R17.htm 100160 - Disclosure - Defined Contribution Plan Sheet http://www.ultragenyx.com/20171231/taxonomy/role/DisclosureDefinedContributionPlan Defined Contribution Plan Notes 17 false false R18.htm 100170 - Disclosure - Income Taxes Sheet http://www.ultragenyx.com/20171231/taxonomy/role/DisclosureIncomeTaxes Income Taxes Notes 18 false false R19.htm 100180 - Disclosure - Commitments and Contingencies Sheet http://www.ultragenyx.com/20171231/taxonomy/role/DisclosureCommitmentsAndContingencies Commitments and Contingencies Notes 19 false false R20.htm 100190 - Disclosure - Net Loss per Share Sheet http://www.ultragenyx.com/20171231/taxonomy/role/DisclosureNetLossPerShare Net Loss per Share Notes 20 false false R21.htm 100200 - Disclosure - Accumulated Other Comprehensive Income (Loss) Sheet http://www.ultragenyx.com/20171231/taxonomy/role/DisclosureAccumulatedOtherComprehensiveIncomeLoss Accumulated Other Comprehensive Income (Loss) Notes 21 false false R22.htm 100210 - Disclosure - Quarterly Financial Data (unaudited) Sheet http://www.ultragenyx.com/20171231/taxonomy/role/DisclosureQuarterlyFinancialDataUnaudited Quarterly Financial Data (unaudited) Notes 22 false false R23.htm 100220 - Disclosure - Subsequent Events Sheet http://www.ultragenyx.com/20171231/taxonomy/role/DisclosureSubsequentEvents Subsequent Events Notes 23 false false R24.htm 100230 - Disclosure - Summary of Significant Accounting Policies (Policies) Sheet http://www.ultragenyx.com/20171231/taxonomy/role/DisclosureSummaryOfSignificantAccountingPoliciesPolicies Summary of Significant Accounting Policies (Policies) Policies http://www.ultragenyx.com/20171231/taxonomy/role/DisclosureSummaryOfSignificantAccountingPolicies 24 false false R25.htm 100240 - Disclosure - Summary of Significant Accounting Policies (Tables) Sheet http://www.ultragenyx.com/20171231/taxonomy/role/DisclosureSummaryOfSignificantAccountingPoliciesTables Summary of Significant Accounting Policies (Tables) Tables http://www.ultragenyx.com/20171231/taxonomy/role/DisclosureSummaryOfSignificantAccountingPolicies 25 false false R26.htm 100250 - Disclosure - Acquisition (Tables) Sheet http://www.ultragenyx.com/20171231/taxonomy/role/DisclosureAcquisitionTables Acquisition (Tables) Tables http://www.ultragenyx.com/20171231/taxonomy/role/DisclosureAcquisition 26 false false R27.htm 100260 - Disclosure - Fair Value Measurements (Tables) Sheet http://www.ultragenyx.com/20171231/taxonomy/role/DisclosureFairValueMeasurementsTables Fair Value Measurements (Tables) Tables http://www.ultragenyx.com/20171231/taxonomy/role/DisclosureFairValueMeasurements 27 false false R28.htm 100270 - Disclosure - Balance Sheet Components (Tables) Sheet http://www.ultragenyx.com/20171231/taxonomy/role/DisclosureBalanceSheetComponentsTables Balance Sheet Components (Tables) Tables http://www.ultragenyx.com/20171231/taxonomy/role/DisclosureBalanceSheetComponents 28 false false R29.htm 100280 - Disclosure - Stock-Based Awards (Tables) Sheet http://www.ultragenyx.com/20171231/taxonomy/role/DisclosureStockBasedAwardsTables Stock-Based Awards (Tables) Tables http://www.ultragenyx.com/20171231/taxonomy/role/DisclosureStockBasedAwards 29 false false R30.htm 100290 - Disclosure - Income Taxes (Tables) Sheet http://www.ultragenyx.com/20171231/taxonomy/role/DisclosureIncomeTaxesTables Income Taxes (Tables) Tables http://www.ultragenyx.com/20171231/taxonomy/role/DisclosureIncomeTaxes 30 false false R31.htm 100300 - Disclosure - Commitments and Contingencies (Tables) Sheet http://www.ultragenyx.com/20171231/taxonomy/role/DisclosureCommitmentsAndContingenciesTables Commitments and Contingencies (Tables) Tables http://www.ultragenyx.com/20171231/taxonomy/role/DisclosureCommitmentsAndContingencies 31 false false R32.htm 100310 - Disclosure - Net Loss per Share (Tables) Sheet http://www.ultragenyx.com/20171231/taxonomy/role/DisclosureNetLossPerShareTables Net Loss per Share (Tables) Tables http://www.ultragenyx.com/20171231/taxonomy/role/DisclosureNetLossPerShare 32 false false R33.htm 100320 - Disclosure - Accumulated Other Comprehensive Income (Loss) (Tables) Sheet http://www.ultragenyx.com/20171231/taxonomy/role/DisclosureAccumulatedOtherComprehensiveIncomeLossTables Accumulated Other Comprehensive Income (Loss) (Tables) Tables http://www.ultragenyx.com/20171231/taxonomy/role/DisclosureAccumulatedOtherComprehensiveIncomeLoss 33 false false R34.htm 100330 - Disclosure - Quarterly Financial Data (unaudited) (Tables) Sheet http://www.ultragenyx.com/20171231/taxonomy/role/DisclosureQuarterlyFinancialDataUnauditedTables Quarterly Financial Data (unaudited) (Tables) Tables http://www.ultragenyx.com/20171231/taxonomy/role/DisclosureQuarterlyFinancialDataUnaudited 34 false false R35.htm 100340 - Disclosure - Organization and Basis of Presentation - Additional Information (Details) Sheet http://www.ultragenyx.com/20171231/taxonomy/role/DisclosureOrganizationAndBasisOfPresentationAdditionalInformationDetails Organization and Basis of Presentation - Additional Information (Details) Details 35 false false R36.htm 100350 - Disclosure - Summary of Significant Accounting Policies - Summary of Useful Lives of Property and Equipment (Details) Sheet http://www.ultragenyx.com/20171231/taxonomy/role/DisclosureSummaryOfSignificantAccountingPoliciesSummaryOfUsefulLivesOfPropertyAndEquipmentDetails Summary of Significant Accounting Policies - Summary of Useful Lives of Property and Equipment (Details) Details 36 false false R37.htm 100360 - Disclosure - Summary of Significant Accounting Policies - Additional Information (Details) Sheet http://www.ultragenyx.com/20171231/taxonomy/role/DisclosureSummaryOfSignificantAccountingPoliciesAdditionalInformationDetails Summary of Significant Accounting Policies - Additional Information (Details) Details 37 false false R38.htm 100370 - Disclosure - Acquisition - Additional Information (Details) Sheet http://www.ultragenyx.com/20171231/taxonomy/role/DisclosureAcquisitionAdditionalInformationDetails Acquisition - Additional Information (Details) Details 38 false false R39.htm 100380 - Disclosure - Acquisition - Summary of Fair Value of Consideration Transferred (Details) Sheet http://www.ultragenyx.com/20171231/taxonomy/role/DisclosureAcquisitionSummaryOfFairValueOfConsiderationTransferredDetails Acquisition - Summary of Fair Value of Consideration Transferred (Details) Details 39 false false R40.htm 100390 - Disclosure - Acquisition - Summary of Fair Values of Assets Acquired and Liabilities Assumed (Details) Sheet http://www.ultragenyx.com/20171231/taxonomy/role/DisclosureAcquisitionSummaryOfFairValuesOfAssetsAcquiredAndLiabilitiesAssumedDetails Acquisition - Summary of Fair Values of Assets Acquired and Liabilities Assumed (Details) Details 40 false false R41.htm 100400 - Disclosure - Acquisition - Summary of Supplemental Unaudited Pro Forma (Details) Sheet http://www.ultragenyx.com/20171231/taxonomy/role/DisclosureAcquisitionSummaryOfSupplementalUnauditedProFormaDetails Acquisition - Summary of Supplemental Unaudited Pro Forma (Details) Details 41 false false R42.htm 100410 - Disclosure - Fair Value Measurements - Summary of Financial Assets and Liabilities Measured on Recurring Basis (Details) Sheet http://www.ultragenyx.com/20171231/taxonomy/role/DisclosureFairValueMeasurementsSummaryOfFinancialAssetsAndLiabilitiesMeasuredOnRecurringBasisDetails Fair Value Measurements - Summary of Financial Assets and Liabilities Measured on Recurring Basis (Details) Details 42 false false R43.htm 100420 - Disclosure - Balance Sheet Components - Summary of Fair Values of Cash Equivalents, Short-Term Investments and Long-Term Investments Classified as Available-for-Sale Securities (Details) Sheet http://www.ultragenyx.com/20171231/taxonomy/role/DisclosureBalanceSheetComponentsSummaryOfFairValuesOfCashEquivalentsShortTermInvestmentsAndLongTermInvestmentsClassifiedAsAvailableForSaleSecuritiesDetails Balance Sheet Components - Summary of Fair Values of Cash Equivalents, Short-Term Investments and Long-Term Investments Classified as Available-for-Sale Securities (Details) Details 43 false false R44.htm 100430 - Disclosure - Balance Sheet Components - Additional Information (Details) Sheet http://www.ultragenyx.com/20171231/taxonomy/role/DisclosureBalanceSheetComponentsAdditionalInformationDetails Balance Sheet Components - Additional Information (Details) Details 44 false false R45.htm 100440 - Disclosure - Balance Sheet Components - Summary of Inventory (Details) Sheet http://www.ultragenyx.com/20171231/taxonomy/role/DisclosureBalanceSheetComponentsSummaryOfInventoryDetails Balance Sheet Components - Summary of Inventory (Details) Details 45 false false R46.htm 100450 - Disclosure - Balance Sheet Components - Summary of Property and Equipment (Details) Sheet http://www.ultragenyx.com/20171231/taxonomy/role/DisclosureBalanceSheetComponentsSummaryOfPropertyAndEquipmentDetails Balance Sheet Components - Summary of Property and Equipment (Details) Details 46 false false R47.htm 100460 - Disclosure - Balance Sheet Components - Accrued Liabilities (Details) Sheet http://www.ultragenyx.com/20171231/taxonomy/role/DisclosureBalanceSheetComponentsAccruedLiabilitiesDetails Balance Sheet Components - Accrued Liabilities (Details) Details 47 false false R48.htm 100470 - Disclosure - Intangible Assets, Net - Additional Information (Details) Sheet http://www.ultragenyx.com/20171231/taxonomy/role/DisclosureIntangibleAssetsNetAdditionalInformationDetails Intangible Assets, Net - Additional Information (Details) Details 48 false false R49.htm 100480 - Disclosure - License and Research Agreements - Additional Information (Details) Sheet http://www.ultragenyx.com/20171231/taxonomy/role/DisclosureLicenseAndResearchAgreementsAdditionalInformationDetails License and Research Agreements - Additional Information (Details) Details 49 false false R50.htm 100490 - Disclosure - Equity - Additional Information (Details) Sheet http://www.ultragenyx.com/20171231/taxonomy/role/DisclosureEquityAdditionalInformationDetails Equity - Additional Information (Details) Details 50 false false R51.htm 100500 - Disclosure - Stock-Based Awards - Additional Information (Details) Sheet http://www.ultragenyx.com/20171231/taxonomy/role/DisclosureStockBasedAwardsAdditionalInformationDetails Stock-Based Awards - Additional Information (Details) Details 51 false false R52.htm 100510 - Disclosure - Stock-Based Awards - Summary of Activity Under Stock Option Plans Including 2011 Plan and 2014 Plan (Details) Sheet http://www.ultragenyx.com/20171231/taxonomy/role/DisclosureStockBasedAwardsSummaryOfActivityUnderStockOptionPlansIncluding2011PlanAnd2014PlanDetails Stock-Based Awards - Summary of Activity Under Stock Option Plans Including 2011 Plan and 2014 Plan (Details) Details 52 false false R53.htm 100520 - Disclosure - Stock-Based Awards - Summary of Activity Under Restricted Stock Units (RSUs) from 2014 Plan (Details) Sheet http://www.ultragenyx.com/20171231/taxonomy/role/DisclosureStockBasedAwardsSummaryOfActivityUnderRestrictedStockUnitsRsusFrom2014PlanDetails Stock-Based Awards - Summary of Activity Under Restricted Stock Units (RSUs) from 2014 Plan (Details) Details 53 false false R54.htm 100530 - Disclosure - Stock-Based Awards - Summary of Stock-Based Compensation Recognized (Details) Sheet http://www.ultragenyx.com/20171231/taxonomy/role/DisclosureStockBasedAwardsSummaryOfStockBasedCompensationRecognizedDetails Stock-Based Awards - Summary of Stock-Based Compensation Recognized (Details) Details 54 false false R55.htm 100540 - Disclosure - Stock-Based Awards - Fair Value of Stock Option Awards Granted Estimated Using Black-Scholes Option-Pricing Model (Details) Sheet http://www.ultragenyx.com/20171231/taxonomy/role/DisclosureStockBasedAwardsFairValueOfStockOptionAwardsGrantedEstimatedUsingBlackScholesOptionPricingModelDetails Stock-Based Awards - Fair Value of Stock Option Awards Granted Estimated Using Black-Scholes Option-Pricing Model (Details) Details 55 false false R56.htm 100550 - Disclosure - Defined Contribution Plan - Additional Information (Details) Sheet http://www.ultragenyx.com/20171231/taxonomy/role/DisclosureDefinedContributionPlanAdditionalInformationDetails Defined Contribution Plan - Additional Information (Details) Details 56 false false R57.htm 100560 - Disclosure - Income Taxes - Components of Company's Loss Before Income Taxes (Details) Sheet http://www.ultragenyx.com/20171231/taxonomy/role/DisclosureIncomeTaxesComponentsOfCompanySLossBeforeIncomeTaxesDetails Income Taxes - Components of Company's Loss Before Income Taxes (Details) Details 57 false false R58.htm 100570 - Disclosure - Income Taxes - Components of Company's Income Tax Provision (Details) Sheet http://www.ultragenyx.com/20171231/taxonomy/role/DisclosureIncomeTaxesComponentsOfCompanySIncomeTaxProvisionDetails Income Taxes - Components of Company's Income Tax Provision (Details) Details 58 false false R59.htm 100580 - Disclosure - Income Taxes - Effective Tax Rate of Provision for Income Taxes from Federal Statutory Rate (Details) Sheet http://www.ultragenyx.com/20171231/taxonomy/role/DisclosureIncomeTaxesEffectiveTaxRateOfProvisionForIncomeTaxesFromFederalStatutoryRateDetails Income Taxes - Effective Tax Rate of Provision for Income Taxes from Federal Statutory Rate (Details) Details 59 false false R60.htm 100590 - Disclosure - Income Taxes - Schedule of Tax Effect of Temporary Differences to Significant Portions of Deferred Tax Assets (Details) Sheet http://www.ultragenyx.com/20171231/taxonomy/role/DisclosureIncomeTaxesScheduleOfTaxEffectOfTemporaryDifferencesToSignificantPortionsOfDeferredTaxAssetsDetails Income Taxes - Schedule of Tax Effect of Temporary Differences to Significant Portions of Deferred Tax Assets (Details) Details 60 false false R61.htm 100600 - Disclosure - Income Taxes - Additional Information (Details) Sheet http://www.ultragenyx.com/20171231/taxonomy/role/DisclosureIncomeTaxesAdditionalInformationDetails Income Taxes - Additional Information (Details) Details 61 false false R62.htm 100610 - Disclosure - Income Taxes - Unrecognized Tax Benefits (Details) Sheet http://www.ultragenyx.com/20171231/taxonomy/role/DisclosureIncomeTaxesUnrecognizedTaxBenefitsDetails Income Taxes - Unrecognized Tax Benefits (Details) Details 62 false false R63.htm 100620 - Disclosure - Commitments and Contingencies - Additional Information (Details) Sheet http://www.ultragenyx.com/20171231/taxonomy/role/DisclosureCommitmentsAndContingenciesAdditionalInformationDetails Commitments and Contingencies - Additional Information (Details) Details 63 false false R64.htm 100630 - Disclosure - Commitments and Contingencies - Summary of Future Minimum Lease Payments under Non-Cancellable Operating Leases Arrangements and Future Payments under Contractually Binding Manufacturing and Service Agreements (Details) Sheet http://www.ultragenyx.com/20171231/taxonomy/role/DisclosureCommitmentsAndContingenciesSummaryOfFutureMinimumLeasePaymentsUnderNonCancellableOperatingLeasesArrangementsAndFuturePaymentsUnderContractuallyBindingManufacturingAndServiceAgreementsDetails Commitments and Contingencies - Summary of Future Minimum Lease Payments under Non-Cancellable Operating Leases Arrangements and Future Payments under Contractually Binding Manufacturing and Service Agreements (Details) Details 64 false false R65.htm 100640 - Disclosure - Net Loss per Share - Computation of Basic and Diluted Net Loss per Share (Details) Sheet http://www.ultragenyx.com/20171231/taxonomy/role/DisclosureNetLossPerShareComputationOfBasicAndDilutedNetLossPerShareDetails Net Loss per Share - Computation of Basic and Diluted Net Loss per Share (Details) Details 65 false false R66.htm 100650 - Disclosure - Net Loss per Share - Outstanding Shares of Common Stock Equivalents Excluded from Computation of Diluted Net Loss per Share (Details) Sheet http://www.ultragenyx.com/20171231/taxonomy/role/DisclosureNetLossPerShareOutstandingSharesOfCommonStockEquivalentsExcludedFromComputationOfDilutedNetLossPerShareDetails Net Loss per Share - Outstanding Shares of Common Stock Equivalents Excluded from Computation of Diluted Net Loss per Share (Details) Details 66 false false R67.htm 100660 - Disclosure - Accumulated Other Comprehensive Income (Loss) - Schedule of Total Accumulated Other Comprehensive Income (Loss) (Details) Sheet http://www.ultragenyx.com/20171231/taxonomy/role/DisclosureAccumulatedOtherComprehensiveIncomeLossScheduleOfTotalAccumulatedOtherComprehensiveIncomeLossDetails Accumulated Other Comprehensive Income (Loss) - Schedule of Total Accumulated Other Comprehensive Income (Loss) (Details) Details http://www.ultragenyx.com/20171231/taxonomy/role/DisclosureAccumulatedOtherComprehensiveIncomeLossTables 67 false false R68.htm 100670 - Disclosure - Quarterly Financial Data (unaudited) - Summary of Unaudited Quarterly Financial Information (Details) Sheet http://www.ultragenyx.com/20171231/taxonomy/role/DisclosureQuarterlyFinancialDataUnauditedSummaryOfUnauditedQuarterlyFinancialInformationDetails Quarterly Financial Data (unaudited) - Summary of Unaudited Quarterly Financial Information (Details) Details http://www.ultragenyx.com/20171231/taxonomy/role/DisclosureQuarterlyFinancialDataUnauditedTables 68 false false R69.htm 100680 - Disclosure - Subsequent Events - Additional Information (Details) Sheet http://www.ultragenyx.com/20171231/taxonomy/role/DisclosureSubsequentEventsAdditionalInformationDetails Subsequent Events - Additional Information (Details) Details 69 false false All Reports Book All Reports rare-20171231.xml rare-20171231.xsd rare-20171231_cal.xml rare-20171231_def.xml rare-20171231_lab.xml rare-20171231_pre.xml http://xbrl.sec.gov/country/2017-01-31 http://fasb.org/us-gaap/2017-01-31 http://xbrl.sec.gov/dei/2014-01-31 true true