| | | | | | | | | | | | | | | | | | | | | |
<?xml version="1.0" encoding="windows-1252"?> |
<FilingSummary> |
| <Version> 3.20.2 </Version> |
| <ProcessingTime/> |
| <ReportFormat> html </ReportFormat> |
| <ContextCount> 150 </ContextCount> |
| <ElementCount> 321 </ElementCount> |
| <EntityCount> 1 </EntityCount> |
| <FootnotesReported> false </FootnotesReported> |
| <SegmentCount> 45 </SegmentCount> |
| <ScenarioCount> 0 </ScenarioCount> |
| <TuplesReported> false </TuplesReported> |
| <UnitCount> 5 </UnitCount> |
| <MyReports> |
| | <Report instance="obln-20200930.xml"> |
| | | <IsDefault> false </IsDefault> |
| | | <HasEmbeddedReports> false </HasEmbeddedReports> |
| | | <HtmlFileName> R1.htm </HtmlFileName> |
| | | <LongName> 0002000 - Document - Document and Entity Information </LongName> |
| | | <ReportType> Sheet </ReportType> |
| | | <Role> http://www.obalon.com/role/DocumentAndEntityInformation </Role> |
| | | <ShortName> Document and Entity Information </ShortName> |
| | | <MenuCategory> Cover </MenuCategory> |
| | | <Position> 1 </Position> |
| | | </Report> |
| | <Report instance="obln-20200930.xml"> |
| | | <IsDefault> false </IsDefault> |
| | | <HasEmbeddedReports> false </HasEmbeddedReports> |
| | | <HtmlFileName> R2.htm </HtmlFileName> |
| | | <LongName> 1001000 - Statement - CONDENSED CONSOLIDATED BALANCE SHEETS </LongName> |
| | | <ReportType> Sheet </ReportType> |
| | | <Role> http://www.obalon.com/role/CondensedConsolidatedBalanceSheets </Role> |
| | | <ShortName> CONDENSED CONSOLIDATED BALANCE SHEETS </ShortName> |
| | | <MenuCategory> Statements </MenuCategory> |
| | | <Position> 2 </Position> |
| | | </Report> |
| | <Report instance="obln-20200930.xml"> |
| | | <IsDefault> false </IsDefault> |
| | | <HasEmbeddedReports> false </HasEmbeddedReports> |
| | | <HtmlFileName> R3.htm </HtmlFileName> |
| | | <LongName> 1001501 - Statement - CONDENSED CONSOLIDATED BALANCE SHEETS (Parenthetical) </LongName> |
| | | <ReportType> Sheet </ReportType> |
| | | <Role> http://www.obalon.com/role/CondensedConsolidatedBalanceSheetsParenthetical </Role> |
| | | <ShortName> CONDENSED CONSOLIDATED BALANCE SHEETS (Parenthetical) </ShortName> |
| | | <MenuCategory> Statements </MenuCategory> |
| | | <Position> 3 </Position> |
| | | </Report> |
| | <Report instance="obln-20200930.xml"> |
| | | <IsDefault> false </IsDefault> |
| | | <HasEmbeddedReports> false </HasEmbeddedReports> |
| | | <HtmlFileName> R4.htm </HtmlFileName> |
| | | <LongName> 1002000 - Statement - CONDENSED CONSOLIDATED STATEMENTS OF OPERATIONS AND COMPREHENSIVE LOSS </LongName> |
| | | <ReportType> Sheet </ReportType> |
| | | <Role> http://www.obalon.com/role/CondensedConsolidatedStatementsOfOperationsAndComprehensiveLoss </Role> |
| | | <ShortName> CONDENSED CONSOLIDATED STATEMENTS OF OPERATIONS AND COMPREHENSIVE LOSS </ShortName> |
| | | <MenuCategory> Statements </MenuCategory> |
| | | <Position> 4 </Position> |
| | | </Report> |
| | <Report instance="obln-20200930.xml"> |
| | | <IsDefault> false </IsDefault> |
| | | <HasEmbeddedReports> false </HasEmbeddedReports> |
| | | <HtmlFileName> R5.htm </HtmlFileName> |
| | | <LongName> 1003000 - Statement - CONDENSED CONSOLIDATED STATEMENTS OF STOCKHOLDERS' EQUITY </LongName> |
| | | <ReportType> Sheet </ReportType> |
| | | <Role> http://www.obalon.com/role/CondensedConsolidatedStatementsOfStockholdersEquity </Role> |
| | | <ShortName> CONDENSED CONSOLIDATED STATEMENTS OF STOCKHOLDERS' EQUITY </ShortName> |
| | | <MenuCategory> Statements </MenuCategory> |
| | | <Position> 5 </Position> |
| | | </Report> |
| | <Report instance="obln-20200930.xml"> |
| | | <IsDefault> false </IsDefault> |
| | | <HasEmbeddedReports> false </HasEmbeddedReports> |
| | | <HtmlFileName> R6.htm </HtmlFileName> |
| | | <LongName> 1004000 - Statement - CONDENSED CONSOLIDATED STATEMENTS OF CASH FLOWS </LongName> |
| | | <ReportType> Sheet </ReportType> |
| | | <Role> http://www.obalon.com/role/CondensedConsolidatedStatementsOfCashFlows </Role> |
| | | <ShortName> CONDENSED CONSOLIDATED STATEMENTS OF CASH FLOWS </ShortName> |
| | | <MenuCategory> Statements </MenuCategory> |
| | | <Position> 6 </Position> |
| | | </Report> |
| | <Report instance="obln-20200930.xml"> |
| | | <IsDefault> false </IsDefault> |
| | | <HasEmbeddedReports> false </HasEmbeddedReports> |
| | | <HtmlFileName> R7.htm </HtmlFileName> |
| | | <LongName> 2101100 - Disclosure - Organization and Basis of Presentation </LongName> |
| | | <ReportType> Sheet </ReportType> |
| | | <Role> http://www.obalon.com/role/OrganizationAndBasisOfPresentation </Role> |
| | | <ShortName> Organization and Basis of Presentation </ShortName> |
| | | <MenuCategory> Notes </MenuCategory> |
| | | <Position> 7 </Position> |
| | | </Report> |
| | <Report instance="obln-20200930.xml"> |
| | | <IsDefault> false </IsDefault> |
| | | <HasEmbeddedReports> false </HasEmbeddedReports> |
| | | <HtmlFileName> R8.htm </HtmlFileName> |
| | | <LongName> 2102100 - Disclosure - Summary of Significant Accounting Policies </LongName> |
| | | <ReportType> Sheet </ReportType> |
| | | <Role> http://www.obalon.com/role/SummaryOfSignificantAccountingPolicies </Role> |
| | | <ShortName> Summary of Significant Accounting Policies </ShortName> |
| | | <MenuCategory> Notes </MenuCategory> |
| | | <Position> 8 </Position> |
| | | </Report> |
| | <Report instance="obln-20200930.xml"> |
| | | <IsDefault> false </IsDefault> |
| | | <HasEmbeddedReports> false </HasEmbeddedReports> |
| | | <HtmlFileName> R9.htm </HtmlFileName> |
| | | <LongName> 2103100 - Disclosure - Fair Value Measurements </LongName> |
| | | <ReportType> Sheet </ReportType> |
| | | <Role> http://www.obalon.com/role/FairValueMeasurements </Role> |
| | | <ShortName> Fair Value Measurements </ShortName> |
| | | <MenuCategory> Notes </MenuCategory> |
| | | <Position> 9 </Position> |
| | | </Report> |
| | <Report instance="obln-20200930.xml"> |
| | | <IsDefault> false </IsDefault> |
| | | <HasEmbeddedReports> false </HasEmbeddedReports> |
| | | <HtmlFileName> R10.htm </HtmlFileName> |
| | | <LongName> 2104100 - Disclosure - Net Loss per Share </LongName> |
| | | <ReportType> Sheet </ReportType> |
| | | <Role> http://www.obalon.com/role/NetLossPerShare </Role> |
| | | <ShortName> Net Loss per Share </ShortName> |
| | | <MenuCategory> Notes </MenuCategory> |
| | | <Position> 10 </Position> |
| | | </Report> |
| | <Report instance="obln-20200930.xml"> |
| | | <IsDefault> false </IsDefault> |
| | | <HasEmbeddedReports> false </HasEmbeddedReports> |
| | | <HtmlFileName> R11.htm </HtmlFileName> |
| | | <LongName> 2105100 - Disclosure - Balance Sheet Details </LongName> |
| | | <ReportType> Sheet </ReportType> |
| | | <Role> http://www.obalon.com/role/BalanceSheetDetails </Role> |
| | | <ShortName> Balance Sheet Details </ShortName> |
| | | <MenuCategory> Notes </MenuCategory> |
| | | <Position> 11 </Position> |
| | | </Report> |
| | <Report instance="obln-20200930.xml"> |
| | | <IsDefault> false </IsDefault> |
| | | <HasEmbeddedReports> false </HasEmbeddedReports> |
| | | <HtmlFileName> R12.htm </HtmlFileName> |
| | | <LongName> 2106100 - Disclosure - Loan </LongName> |
| | | <ReportType> Sheet </ReportType> |
| | | <Role> http://www.obalon.com/role/Loan </Role> |
| | | <ShortName> Loan </ShortName> |
| | | <MenuCategory> Notes </MenuCategory> |
| | | <Position> 12 </Position> |
| | | </Report> |
| | <Report instance="obln-20200930.xml"> |
| | | <IsDefault> false </IsDefault> |
| | | <HasEmbeddedReports> false </HasEmbeddedReports> |
| | | <HtmlFileName> R13.htm </HtmlFileName> |
| | | <LongName> 2107100 - Disclosure - Stock-Based Compensation </LongName> |
| | | <ReportType> Sheet </ReportType> |
| | | <Role> http://www.obalon.com/role/StockBasedCompensation </Role> |
| | | <ShortName> Stock-Based Compensation </ShortName> |
| | | <MenuCategory> Notes </MenuCategory> |
| | | <Position> 13 </Position> |
| | | </Report> |
| | <Report instance="obln-20200930.xml"> |
| | | <IsDefault> false </IsDefault> |
| | | <HasEmbeddedReports> false </HasEmbeddedReports> |
| | | <HtmlFileName> R14.htm </HtmlFileName> |
| | | <LongName> 2108100 - Disclosure - Stockholders' Equity </LongName> |
| | | <ReportType> Sheet </ReportType> |
| | | <Role> http://www.obalon.com/role/StockholdersEquity </Role> |
| | | <ShortName> Stockholders' Equity </ShortName> |
| | | <MenuCategory> Notes </MenuCategory> |
| | | <Position> 14 </Position> |
| | | </Report> |
| | <Report instance="obln-20200930.xml"> |
| | | <IsDefault> false </IsDefault> |
| | | <HasEmbeddedReports> false </HasEmbeddedReports> |
| | | <HtmlFileName> R15.htm </HtmlFileName> |
| | | <LongName> 2109100 - Disclosure - Income Taxes </LongName> |
| | | <ReportType> Sheet </ReportType> |
| | | <Role> http://www.obalon.com/role/IncomeTaxes </Role> |
| | | <ShortName> Income Taxes </ShortName> |
| | | <MenuCategory> Notes </MenuCategory> |
| | | <Position> 15 </Position> |
| | | </Report> |
| | <Report instance="obln-20200930.xml"> |
| | | <IsDefault> false </IsDefault> |
| | | <HasEmbeddedReports> false </HasEmbeddedReports> |
| | | <HtmlFileName> R16.htm </HtmlFileName> |
| | | <LongName> 2110100 - Disclosure - Commitments and Contingencies </LongName> |
| | | <ReportType> Sheet </ReportType> |
| | | <Role> http://www.obalon.com/role/CommitmentsAndContingencies </Role> |
| | | <ShortName> Commitments and Contingencies </ShortName> |
| | | <MenuCategory> Notes </MenuCategory> |
| | | <Position> 16 </Position> |
| | | </Report> |
| | <Report instance="obln-20200930.xml"> |
| | | <IsDefault> false </IsDefault> |
| | | <HasEmbeddedReports> false </HasEmbeddedReports> |
| | | <HtmlFileName> R17.htm </HtmlFileName> |
| | | <LongName> 2111100 - Disclosure - Variable Interest Entity </LongName> |
| | | <ReportType> Sheet </ReportType> |
| | | <Role> http://www.obalon.com/role/VariableInterestEntity </Role> |
| | | <ShortName> Variable Interest Entity </ShortName> |
| | | <MenuCategory> Notes </MenuCategory> |
| | | <Position> 17 </Position> |
| | | </Report> |
| | <Report instance="obln-20200930.xml"> |
| | | <IsDefault> false </IsDefault> |
| | | <HasEmbeddedReports> false </HasEmbeddedReports> |
| | | <HtmlFileName> R18.htm </HtmlFileName> |
| | | <LongName> 2202201 - Disclosure - Summary of Significant Accounting Policies (Policies) </LongName> |
| | | <ReportType> Sheet </ReportType> |
| | | <Role> http://www.obalon.com/role/SummaryOfSignificantAccountingPoliciesPolicies </Role> |
| | | <ShortName> Summary of Significant Accounting Policies (Policies) </ShortName> |
| | | <MenuCategory> Policies </MenuCategory> |
| | | <ParentRole> http://www.obalon.com/role/SummaryOfSignificantAccountingPolicies </ParentRole> |
| | | <Position> 18 </Position> |
| | | </Report> |
| | <Report instance="obln-20200930.xml"> |
| | | <IsDefault> false </IsDefault> |
| | | <HasEmbeddedReports> false </HasEmbeddedReports> |
| | | <HtmlFileName> R19.htm </HtmlFileName> |
| | | <LongName> 2303301 - Disclosure - Fair Value Measurements (Tables) </LongName> |
| | | <ReportType> Sheet </ReportType> |
| | | <Role> http://www.obalon.com/role/FairValueMeasurementsTables </Role> |
| | | <ShortName> Fair Value Measurements (Tables) </ShortName> |
| | | <MenuCategory> Tables </MenuCategory> |
| | | <ParentRole> http://www.obalon.com/role/FairValueMeasurements </ParentRole> |
| | | <Position> 19 </Position> |
| | | </Report> |
| | <Report instance="obln-20200930.xml"> |
| | | <IsDefault> false </IsDefault> |
| | | <HasEmbeddedReports> false </HasEmbeddedReports> |
| | | <HtmlFileName> R20.htm </HtmlFileName> |
| | | <LongName> 2304301 - Disclosure - Net Loss per Share (Tables) </LongName> |
| | | <ReportType> Sheet </ReportType> |
| | | <Role> http://www.obalon.com/role/NetLossPerShareTables </Role> |
| | | <ShortName> Net Loss per Share (Tables) </ShortName> |
| | | <MenuCategory> Tables </MenuCategory> |
| | | <ParentRole> http://www.obalon.com/role/NetLossPerShare </ParentRole> |
| | | <Position> 20 </Position> |
| | | </Report> |
| | <Report instance="obln-20200930.xml"> |
| | | <IsDefault> false </IsDefault> |
| | | <HasEmbeddedReports> false </HasEmbeddedReports> |
| | | <HtmlFileName> R21.htm </HtmlFileName> |
| | | <LongName> 2305301 - Disclosure - Balance Sheet Details (Tables) </LongName> |
| | | <ReportType> Sheet </ReportType> |
| | | <Role> http://www.obalon.com/role/BalanceSheetDetailsTables </Role> |
| | | <ShortName> Balance Sheet Details (Tables) </ShortName> |
| | | <MenuCategory> Tables </MenuCategory> |
| | | <ParentRole> http://www.obalon.com/role/BalanceSheetDetails </ParentRole> |
| | | <Position> 21 </Position> |
| | | </Report> |
| | <Report instance="obln-20200930.xml"> |
| | | <IsDefault> false </IsDefault> |
| | | <HasEmbeddedReports> false </HasEmbeddedReports> |
| | | <HtmlFileName> R22.htm </HtmlFileName> |
| | | <LongName> 2307301 - Disclosure - Stock-Based Compensation (Tables) </LongName> |
| | | <ReportType> Sheet </ReportType> |
| | | <Role> http://www.obalon.com/role/StockBasedCompensationTables </Role> |
| | | <ShortName> Stock-Based Compensation (Tables) </ShortName> |
| | | <MenuCategory> Tables </MenuCategory> |
| | | <ParentRole> http://www.obalon.com/role/StockBasedCompensation </ParentRole> |
| | | <Position> 22 </Position> |
| | | </Report> |
| | <Report instance="obln-20200930.xml"> |
| | | <IsDefault> false </IsDefault> |
| | | <HasEmbeddedReports> false </HasEmbeddedReports> |
| | | <HtmlFileName> R23.htm </HtmlFileName> |
| | | <LongName> 2308301 - Disclosure - Stockholders' Equity (Tables) </LongName> |
| | | <ReportType> Sheet </ReportType> |
| | | <Role> http://www.obalon.com/role/StockholdersEquityTables </Role> |
| | | <ShortName> Stockholders' Equity (Tables) </ShortName> |
| | | <MenuCategory> Tables </MenuCategory> |
| | | <ParentRole> http://www.obalon.com/role/StockholdersEquity </ParentRole> |
| | | <Position> 23 </Position> |
| | | </Report> |
| | <Report instance="obln-20200930.xml"> |
| | | <IsDefault> false </IsDefault> |
| | | <HasEmbeddedReports> false </HasEmbeddedReports> |
| | | <HtmlFileName> R24.htm </HtmlFileName> |
| | | <LongName> 2310301 - Disclosure - Commitments and Contingencies (Tables) </LongName> |
| | | <ReportType> Sheet </ReportType> |
| | | <Role> http://www.obalon.com/role/CommitmentsAndContingenciesTables </Role> |
| | | <ShortName> Commitments and Contingencies (Tables) </ShortName> |
| | | <MenuCategory> Tables </MenuCategory> |
| | | <ParentRole> http://www.obalon.com/role/CommitmentsAndContingencies </ParentRole> |
| | | <Position> 24 </Position> |
| | | </Report> |
| | <Report instance="obln-20200930.xml"> |
| | | <IsDefault> false </IsDefault> |
| | | <HasEmbeddedReports> false </HasEmbeddedReports> |
| | | <HtmlFileName> R25.htm </HtmlFileName> |
| | | <LongName> 2401401 - Disclosure - Organization and Basis of Presentation - Additional Information (Detail) </LongName> |
| | | <ReportType> Sheet </ReportType> |
| | | <Role> http://www.obalon.com/role/OrganizationAndBasisOfPresentationAdditionalInformationDetail </Role> |
| | | <ShortName> Organization and Basis of Presentation - Additional Information (Detail) </ShortName> |
| | | <MenuCategory> Details </MenuCategory> |
| | | <Position> 25 </Position> |
| | | </Report> |
| | <Report instance="obln-20200930.xml"> |
| | | <IsDefault> false </IsDefault> |
| | | <HasEmbeddedReports> false </HasEmbeddedReports> |
| | | <HtmlFileName> R26.htm </HtmlFileName> |
| | | <LongName> 2402402 - Disclosure - Summary of Significant Accounting Policies - Narrative (Details) </LongName> |
| | | <ReportType> Sheet </ReportType> |
| | | <Role> http://www.obalon.com/role/SummaryOfSignificantAccountingPoliciesNarrativeDetails </Role> |
| | | <ShortName> Summary of Significant Accounting Policies - Narrative (Details) </ShortName> |
| | | <MenuCategory> Details </MenuCategory> |
| | | <Position> 26 </Position> |
| | | </Report> |
| | <Report instance="obln-20200930.xml"> |
| | | <IsDefault> false </IsDefault> |
| | | <HasEmbeddedReports> false </HasEmbeddedReports> |
| | | <HtmlFileName> R27.htm </HtmlFileName> |
| | | <LongName> 2403402 - Disclosure - Fair Value Measurements - Schedule of Assets and Liabilities Measured at Fair Value on Recurring Basis (Details) </LongName> |
| | | <ReportType> Sheet </ReportType> |
| | | <Role> http://www.obalon.com/role/FairValueMeasurementsScheduleOfAssetsAndLiabilitiesMeasuredAtFairValueOnRecurringBasisDetails </Role> |
| | | <ShortName> Fair Value Measurements - Schedule of Assets and Liabilities Measured at Fair Value on Recurring Basis (Details) </ShortName> |
| | | <MenuCategory> Details </MenuCategory> |
| | | <Position> 27 </Position> |
| | | </Report> |
| | <Report instance="obln-20200930.xml"> |
| | | <IsDefault> false </IsDefault> |
| | | <HasEmbeddedReports> false </HasEmbeddedReports> |
| | | <HtmlFileName> R28.htm </HtmlFileName> |
| | | <LongName> 2403403 - Disclosure - Fair Value Measurements - Schedule of Fair Value Assumptions (Details) </LongName> |
| | | <ReportType> Sheet </ReportType> |
| | | <Role> http://www.obalon.com/role/FairValueMeasurementsScheduleOfFairValueAssumptionsDetails </Role> |
| | | <ShortName> Fair Value Measurements - Schedule of Fair Value Assumptions (Details) </ShortName> |
| | | <MenuCategory> Details </MenuCategory> |
| | | <Position> 28 </Position> |
| | | </Report> |
| | <Report instance="obln-20200930.xml"> |
| | | <IsDefault> false </IsDefault> |
| | | <HasEmbeddedReports> false </HasEmbeddedReports> |
| | | <HtmlFileName> R29.htm </HtmlFileName> |
| | | <LongName> 2403404 - Disclosure - Fair Value Measurements - Schedule of Liabilities Measured at Fair Value (Details) </LongName> |
| | | <ReportType> Sheet </ReportType> |
| | | <Role> http://www.obalon.com/role/FairValueMeasurementsScheduleOfLiabilitiesMeasuredAtFairValueDetails </Role> |
| | | <ShortName> Fair Value Measurements - Schedule of Liabilities Measured at Fair Value (Details) </ShortName> |
| | | <MenuCategory> Details </MenuCategory> |
| | | <Position> 29 </Position> |
| | | </Report> |
| | <Report instance="obln-20200930.xml"> |
| | | <IsDefault> false </IsDefault> |
| | | <HasEmbeddedReports> false </HasEmbeddedReports> |
| | | <HtmlFileName> R30.htm </HtmlFileName> |
| | | <LongName> 2404402 - Disclosure - Net Loss per Share - Schedule of Computation of Basic and Diluted Net Loss Per Share of Common Stock (Details) </LongName> |
| | | <ReportType> Sheet </ReportType> |
| | | <Role> http://www.obalon.com/role/NetLossPerShareScheduleOfComputationOfBasicAndDilutedNetLossPerShareOfCommonStockDetails </Role> |
| | | <ShortName> Net Loss per Share - Schedule of Computation of Basic and Diluted Net Loss Per Share of Common Stock (Details) </ShortName> |
| | | <MenuCategory> Details </MenuCategory> |
| | | <Position> 30 </Position> |
| | | </Report> |
| | <Report instance="obln-20200930.xml"> |
| | | <IsDefault> false </IsDefault> |
| | | <HasEmbeddedReports> false </HasEmbeddedReports> |
| | | <HtmlFileName> R31.htm </HtmlFileName> |
| | | <LongName> 2404403 - Disclosure - Net Loss per Share - Schedule of Anti-Dilutive Common Stock Equivalents Excluded from the Calculation of Diluted Net Loss Per Share (Details) </LongName> |
| | | <ReportType> Sheet </ReportType> |
| | | <Role> http://www.obalon.com/role/NetLossPerShareScheduleOfAntiDilutiveCommonStockEquivalentsExcludedFromCalculationOfDilutedNetLossPerShareDetails </Role> |
| | | <ShortName> Net Loss per Share - Schedule of Anti-Dilutive Common Stock Equivalents Excluded from the Calculation of Diluted Net Loss Per Share (Details) </ShortName> |
| | | <MenuCategory> Details </MenuCategory> |
| | | <Position> 31 </Position> |
| | | </Report> |
| | <Report instance="obln-20200930.xml"> |
| | | <IsDefault> false </IsDefault> |
| | | <HasEmbeddedReports> false </HasEmbeddedReports> |
| | | <HtmlFileName> R32.htm </HtmlFileName> |
| | | <LongName> 2405402 - Disclosure - Balance Sheet Details - Schedule of Inventory (Details) </LongName> |
| | | <ReportType> Sheet </ReportType> |
| | | <Role> http://www.obalon.com/role/BalanceSheetDetailsScheduleOfInventoryDetails </Role> |
| | | <ShortName> Balance Sheet Details - Schedule of Inventory (Details) </ShortName> |
| | | <MenuCategory> Details </MenuCategory> |
| | | <Position> 32 </Position> |
| | | </Report> |
| | <Report instance="obln-20200930.xml"> |
| | | <IsDefault> false </IsDefault> |
| | | <HasEmbeddedReports> false </HasEmbeddedReports> |
| | | <HtmlFileName> R33.htm </HtmlFileName> |
| | | <LongName> 2405403 - Disclosure - Balance Sheet Details - Narrative (Details) </LongName> |
| | | <ReportType> Sheet </ReportType> |
| | | <Role> http://www.obalon.com/role/BalanceSheetDetailsNarrativeDetails </Role> |
| | | <ShortName> Balance Sheet Details - Narrative (Details) </ShortName> |
| | | <MenuCategory> Details </MenuCategory> |
| | | <Position> 33 </Position> |
| | | </Report> |
| | <Report instance="obln-20200930.xml"> |
| | | <IsDefault> false </IsDefault> |
| | | <HasEmbeddedReports> false </HasEmbeddedReports> |
| | | <HtmlFileName> R34.htm </HtmlFileName> |
| | | <LongName> 2405404 - Disclosure - Balance Sheet Details - Schedule of Other Current Assets (Details) </LongName> |
| | | <ReportType> Sheet </ReportType> |
| | | <Role> http://www.obalon.com/role/BalanceSheetDetailsScheduleOfOtherCurrentAssetsDetails </Role> |
| | | <ShortName> Balance Sheet Details - Schedule of Other Current Assets (Details) </ShortName> |
| | | <MenuCategory> Details </MenuCategory> |
| | | <Position> 34 </Position> |
| | | </Report> |
| | <Report instance="obln-20200930.xml"> |
| | | <IsDefault> false </IsDefault> |
| | | <HasEmbeddedReports> false </HasEmbeddedReports> |
| | | <HtmlFileName> R35.htm </HtmlFileName> |
| | | <LongName> 2405405 - Disclosure - Balance Sheet Details - Schedule of Property and Equipment, Net (Details) </LongName> |
| | | <ReportType> Sheet </ReportType> |
| | | <Role> http://www.obalon.com/role/BalanceSheetDetailsScheduleOfPropertyAndEquipmentNetDetails </Role> |
| | | <ShortName> Balance Sheet Details - Schedule of Property and Equipment, Net (Details) </ShortName> |
| | | <MenuCategory> Details </MenuCategory> |
| | | <Position> 35 </Position> |
| | | </Report> |
| | <Report instance="obln-20200930.xml"> |
| | | <IsDefault> false </IsDefault> |
| | | <HasEmbeddedReports> false </HasEmbeddedReports> |
| | | <HtmlFileName> R36.htm </HtmlFileName> |
| | | <LongName> 2405406 - Disclosure - Balance Sheet Details - Schedule of Other Current Liabilities (Details) </LongName> |
| | | <ReportType> Sheet </ReportType> |
| | | <Role> http://www.obalon.com/role/BalanceSheetDetailsScheduleOfOtherCurrentLiabilitiesDetails </Role> |
| | | <ShortName> Balance Sheet Details - Schedule of Other Current Liabilities (Details) </ShortName> |
| | | <MenuCategory> Details </MenuCategory> |
| | | <Position> 36 </Position> |
| | | </Report> |
| | <Report instance="obln-20200930.xml"> |
| | | <IsDefault> false </IsDefault> |
| | | <HasEmbeddedReports> false </HasEmbeddedReports> |
| | | <HtmlFileName> R37.htm </HtmlFileName> |
| | | <LongName> 2406401 - Disclosure - Loan - Additional Information (Details) </LongName> |
| | | <ReportType> Sheet </ReportType> |
| | | <Role> http://www.obalon.com/role/LoanAdditionalInformationDetails </Role> |
| | | <ShortName> Loan - Additional Information (Details) </ShortName> |
| | | <MenuCategory> Details </MenuCategory> |
| | | <Position> 37 </Position> |
| | | </Report> |
| | <Report instance="obln-20200930.xml"> |
| | | <IsDefault> false </IsDefault> |
| | | <HasEmbeddedReports> false </HasEmbeddedReports> |
| | | <HtmlFileName> R38.htm </HtmlFileName> |
| | | <LongName> 2407402 - Disclosure - Stock-Based Compensation - Additional Information (Details) </LongName> |
| | | <ReportType> Sheet </ReportType> |
| | | <Role> http://www.obalon.com/role/StockBasedCompensationAdditionalInformationDetails </Role> |
| | | <ShortName> Stock-Based Compensation - Additional Information (Details) </ShortName> |
| | | <MenuCategory> Details </MenuCategory> |
| | | <Position> 38 </Position> |
| | | </Report> |
| | <Report instance="obln-20200930.xml"> |
| | | <IsDefault> false </IsDefault> |
| | | <HasEmbeddedReports> false </HasEmbeddedReports> |
| | | <HtmlFileName> R39.htm </HtmlFileName> |
| | | <LongName> 2407403 - Disclosure - Stock-Based Compensation - Summary of Stock-Based Compensation (Details) </LongName> |
| | | <ReportType> Sheet </ReportType> |
| | | <Role> http://www.obalon.com/role/StockBasedCompensationSummaryOfStockBasedCompensationDetails </Role> |
| | | <ShortName> Stock-Based Compensation - Summary of Stock-Based Compensation (Details) </ShortName> |
| | | <MenuCategory> Details </MenuCategory> |
| | | <Position> 39 </Position> |
| | | </Report> |
| | <Report instance="obln-20200930.xml"> |
| | | <IsDefault> false </IsDefault> |
| | | <HasEmbeddedReports> false </HasEmbeddedReports> |
| | | <HtmlFileName> R40.htm </HtmlFileName> |
| | | <LongName> 2407404 - Disclosure - Stock-Based Compensation - Summary of Stock Option Transactions (Details) </LongName> |
| | | <ReportType> Sheet </ReportType> |
| | | <Role> http://www.obalon.com/role/StockBasedCompensationSummaryOfStockOptionTransactionsDetails </Role> |
| | | <ShortName> Stock-Based Compensation - Summary of Stock Option Transactions (Details) </ShortName> |
| | | <MenuCategory> Details </MenuCategory> |
| | | <Position> 40 </Position> |
| | | </Report> |
| | <Report instance="obln-20200930.xml"> |
| | | <IsDefault> false </IsDefault> |
| | | <HasEmbeddedReports> false </HasEmbeddedReports> |
| | | <HtmlFileName> R41.htm </HtmlFileName> |
| | | <LongName> 2407405 - Disclosure - Stock-Based Compensation - Summary of Restricted Stock Awards (Details) </LongName> |
| | | <ReportType> Sheet </ReportType> |
| | | <Role> http://www.obalon.com/role/StockBasedCompensationSummaryOfRestrictedStockAwardsDetails </Role> |
| | | <ShortName> Stock-Based Compensation - Summary of Restricted Stock Awards (Details) </ShortName> |
| | | <MenuCategory> Details </MenuCategory> |
| | | <Position> 41 </Position> |
| | | </Report> |
| | <Report instance="obln-20200930.xml"> |
| | | <IsDefault> false </IsDefault> |
| | | <HasEmbeddedReports> false </HasEmbeddedReports> |
| | | <HtmlFileName> R42.htm </HtmlFileName> |
| | | <LongName> 2408402 - Disclosure - Stockholders' Equity - Additional Information (Details) </LongName> |
| | | <ReportType> Sheet </ReportType> |
| | | <Role> http://www.obalon.com/role/StockholdersEquityAdditionalInformationDetails </Role> |
| | | <ShortName> Stockholders' Equity - Additional Information (Details) </ShortName> |
| | | <MenuCategory> Details </MenuCategory> |
| | | <Position> 42 </Position> |
| | | </Report> |
| | <Report instance="obln-20200930.xml"> |
| | | <IsDefault> false </IsDefault> |
| | | <HasEmbeddedReports> false </HasEmbeddedReports> |
| | | <HtmlFileName> R43.htm </HtmlFileName> |
| | | <LongName> 2408403 - Disclosure - Stockholders' Equity - Schedule of Common Stock Reserved for Future Issuance (Details) </LongName> |
| | | <ReportType> Sheet </ReportType> |
| | | <Role> http://www.obalon.com/role/StockholdersEquityScheduleOfCommonStockReservedForFutureIssuanceDetails </Role> |
| | | <ShortName> Stockholders' Equity - Schedule of Common Stock Reserved for Future Issuance (Details) </ShortName> |
| | | <MenuCategory> Details </MenuCategory> |
| | | <Position> 43 </Position> |
| | | </Report> |
| | <Report instance="obln-20200930.xml"> |
| | | <IsDefault> false </IsDefault> |
| | | <HasEmbeddedReports> false </HasEmbeddedReports> |
| | | <HtmlFileName> R44.htm </HtmlFileName> |
| | | <LongName> 2410402 - Disclosure - Commitments and Contingencies - Additional Information (Details) </LongName> |
| | | <ReportType> Sheet </ReportType> |
| | | <Role> http://www.obalon.com/role/CommitmentsAndContingenciesAdditionalInformationDetails </Role> |
| | | <ShortName> Commitments and Contingencies - Additional Information (Details) </ShortName> |
| | | <MenuCategory> Details </MenuCategory> |
| | | <Position> 44 </Position> |
| | | </Report> |
| | <Report instance="obln-20200930.xml"> |
| | | <IsDefault> false </IsDefault> |
| | | <HasEmbeddedReports> false </HasEmbeddedReports> |
| | | <HtmlFileName> R45.htm </HtmlFileName> |
| | | <LongName> 2410403 - Disclosure - Commitments and Contingencies - Schedule of Future Noncancelable Minimum Payment Obligations Under Operating Lease (Details) </LongName> |
| | | <ReportType> Sheet </ReportType> |
| | | <Role> http://www.obalon.com/role/CommitmentsAndContingenciesScheduleOfFutureNoncancelableMinimumPaymentObligationsUnderOperatingLeaseDetails </Role> |
| | | <ShortName> Commitments and Contingencies - Schedule of Future Noncancelable Minimum Payment Obligations Under Operating Lease (Details) </ShortName> |
| | | <MenuCategory> Details </MenuCategory> |
| | | <Position> 45 </Position> |
| | | </Report> |
| | <Report instance="obln-20200930.xml"> |
| | | <IsDefault> false </IsDefault> |
| | | <HasEmbeddedReports> false </HasEmbeddedReports> |
| | | <HtmlFileName> R46.htm </HtmlFileName> |
| | | <LongName> 2411401 - Disclosure - Variable Interest Entity (Details) </LongName> |
| | | <ReportType> Sheet </ReportType> |
| | | <Role> http://www.obalon.com/role/VariableInterestEntityDetails </Role> |
| | | <ShortName> Variable Interest Entity (Details) </ShortName> |
| | | <MenuCategory> Details </MenuCategory> |
| | | <ParentRole> http://www.obalon.com/role/VariableInterestEntity </ParentRole> |
| | | <Position> 46 </Position> |
| | | </Report> |
| | <Report> |
| | | <IsDefault> false </IsDefault> |
| | | <HasEmbeddedReports> false </HasEmbeddedReports> |
| | | <LongName> All Reports </LongName> |
| | | <ReportType> Book </ReportType> |
| | | <ShortName> All Reports </ShortName> |
| | | </Report> |
| | </MyReports> |
| <InputFiles> |
| | <File> obln-20200930.xml </File> |
| | <File> obln-20200930.xsd </File> |
| | <File> obln-20200930_cal.xml </File> |
| | <File> obln-20200930_def.xml </File> |
| | <File> obln-20200930_lab.xml </File> |
| | <File> obln-20200930_pre.xml </File> |
| | </InputFiles> |
| <SupplementalFiles/> |
| <BaseTaxonomies> |
| | <BaseTaxonomy> http://xbrl.sec.gov/dei/2020-01-31 </BaseTaxonomy> |
| | <BaseTaxonomy> http://fasb.org/srt/2020-01-31 </BaseTaxonomy> |
| | <BaseTaxonomy> http://fasb.org/us-gaap/2020-01-31 </BaseTaxonomy> |
| | </BaseTaxonomies> |
| <HasPresentationLinkbase> true </HasPresentationLinkbase> |
| <HasCalculationLinkbase> true </HasCalculationLinkbase> |
| </FilingSummary> |