Trading Arrangements, by Individual Trading Arrangements, by Individual [Table] Trading Arrangement: Trading Arrangement [Axis] Maximum Maximum [Member] Statistical Measurement [Domain] Statistical Measurement [Domain] Title of 12(b) Security Title of 12(b) Security Subsequent event Subsequent Event [Member] Document Fiscal Year Focus Document Fiscal Year Focus Adjustment to Compensation, Amount Adjustment to Compensation Amount Financial Instrument [Axis] Financial Instrument [Axis] Number of Shares Share-Based Compensation Arrangement by Share-Based Payment Award, Equity Instruments Other than Options, Nonvested, Number of Shares [Roll Forward] Common stock, $0.0001 par value; 100,000,000 shares authorized; 44,697,215 and 43,647,131 shares issued and outstanding, respectively Common Stock, Value, Issued 2027 Lessee, Operating Lease, Liability, to be Paid, Year One Accrued compensation and related expenses Employee-related Liabilities, Current Schedule of Outstanding Borrowings Schedule of Long-Term Debt Instruments [Table Text Block] Unrealized Gains Cash Equivalents, Accumulated Gross Unrealized Gain, Before Tax Cash Equivalents, Accumulated Gross Unrealized Gain, Before Tax Cash equivalents Cash Equivalents, at Carrying Value [Abstract] Line of credit Line of Credit [Member] Restatement Determination Date Restatement Determination Date Short-term investments Debt Securities, Available-for-Sale, Fair Value to Amortized Cost, after Allowance for Credit Loss [Abstract] Laura A. Francis [Member] Laura A. Francis Class of Warrant or Right [Domain] Class of Warrant or Right [Domain] Inventory reserve Inventory Write-down Future principal and final fee payments Maturities of Long-Term Debt [Abstract] Balance at beginning of period Balance at end of period Accounts Receivable, Allowance for Credit Loss Options vested and expected to vest (in dollars per share) Share-Based Compensation Arrangement by Share-Based Payment Award, Options, Vested and Expected to Vest, Outstanding, Weighted Average Exercise Price Amendment Flag Amendment Flag Current liabilities: Liabilities, Current [Abstract] Accounts receivable credit losses Provision Accounts Receivable, Credit Loss Expense (Reversal) Entity Common Stock, Shares Outstanding Entity Common Stock, Shares Outstanding Class of Warrant or Right [Table] Class of Warrant or Right [Table] Marketable Securities [Line Items] Marketable Securities [Line Items] Unrealized Losses Debt Securities, Available-for-Sale, Accumulated Gross Unrealized Loss, before Tax Adjustment to Non-PEO NEO Compensation Footnote Adjustment to Non-PEO NEO Compensation Footnote [Text Block] Entity Address, State or Province Entity Address, State or Province ESPP purchase rights Employee Stock Purchase Plan Shares [Member] Employee Stock Purchase Plan Shares [Member] Stock options granted (in shares) Share-Based Compensation Arrangement by Share-Based Payment Award, Options, Grants in Period, Gross Changes in foreign currency translation Foreign currency translation Other Comprehensive Income (Loss), Foreign Currency Transaction and Translation Adjustment, Net of Tax, Portion Attributable to Parent PEO Total Compensation Amount PEO Total Compensation Amount Common stock, par value (in dollars per share) Common Stock, Par or Stated Value Per Share Marketable securities Assets, Fair Value Disclosure [Abstract] Construction in progress, surgical placement instrument set Construction in Progress, Surgical Placement Instrument Set [Member] Construction in Progress, Surgical Placement Instrument Set Cash and cash equivalents at Cash and Cash Equivalents [Abstract] Outstanding, beginning of period (in shares) Outstanding, end of period (in shares) Share-Based Compensation Arrangement by Share-Based Payment Award, Equity Instruments Other than Options, Nonvested, Number Weighted-average number of common shares used to compute basic net loss per share (in shares) Weighted-average shares used to compute basic net loss per share (in shares) Weighted Average Number of Shares Outstanding, Basic Amortization of discount and premium on marketable securities Accretion (Amortization) of Discounts and Premiums, Investments Schedule of Stock-Based Compensation Share-Based Payment Arrangement, Activity [Table Text Block] Outstanding Aggregate Erroneous Compensation Amount Outstanding Aggregate Erroneous Compensation Amount Number of reportable segments Number of Reportable Segments Total current liabilities Liabilities, Current 2030 Lessee, Operating Lease, Liability, to be Paid, Year Four Amortized Cost Debt Securities, Available-for-Sale, Amortized Cost, Excluding Accrued Interest, before Allowance for Credit Loss Entity Address, City or Town Entity Address, City or Town Granted (in shares) Share-Based Compensation Arrangement by Share-Based Payment Award, Equity Instruments Other than Options, Grants in Period Share-based Compensation Arrangement by Share-based Payment Award [Line Items] Share-Based Compensation Arrangement by Share-Based Payment Award [Line Items] Statement of Financial Position [Abstract] Statement of Financial Position [Abstract] Award Timing MNPI Disclosure Award Timing MNPI Disclosure [Text Block] Vested (in shares) Share-Based Compensation Arrangement by Share-Based Payment Award, Equity Instruments Other than Options, Vested in Period Basis of Presentation Basis of Accounting, Policy [Policy Text Block] Peer Group Total Shareholder Return Amount Peer Group Total Shareholder Return Amount Proceeds from issuance of common stock under employee stock purchase plan Proceeds from Stock Plans Level 2 Fair Value, Inputs, Level 2 [Member] Total Shareholder Return Vs Peer Group Total Shareholder Return Vs Peer Group [Text Block] Revolving credit facility, aggregate principal amount Line of Credit Facility, Maximum Borrowing Capacity Non-Rule 10b5-1 Arrangement Terminated Non-Rule 10b5-1 Arrangement Terminated [Flag] Warrants Issued 12/22/2016 Warrants Issued December Twenty-Second Twenty Sixteen [Member] Warrants Issued December Twenty-Second Twenty Sixteen [Member] United States UNITED STATES Subsequent Event Type [Axis] Subsequent Event Type [Axis] Schedule of Long-term Debt Instruments [Table] Schedule of Long-Term Debt Instruments [Table] Recent Accounting Pronouncements New Accounting Pronouncements, Policy [Policy Text Block] Unpaid purchases of property and equipment Capital Expenditures Incurred but Not yet Paid Loss on disposal of property and equipment Gain (Loss) on Disposition of Property Plant Equipment Use of Estimates Use of Estimates, Policy [Policy Text Block] Amortization of debt issuance costs Amortization of Debt Issuance Costs Schedule of Accrued Liabilities and Other Schedule of Accrued Liabilities [Table Text Block] Price per Share (in dollars per share) Class of Warrant or Right, Exercise Price of Warrants or Rights Outstanding debt, net of debt issuance costs and unaccreted value of final payment fee Long-Term Debt Schedule of Future Minimum Lease Payments Under Non-Cancelable Operating Leases Lessee, Operating Lease, Liability, to be Paid, Maturity [Table Text Block] Document Period End Date Document Period End Date Changes in operating assets and liabilities: Adjustment to Reconcile Net Income to Cash Provided by (Used in) Operating Activity, Increase (Decrease) in Operating Capital [Abstract] Canceled and forfeited (in shares) Share-Based Compensation Arrangement by Share-Based Payment Award, Options, Forfeitures and Expirations in Period Net cash (used in) provided by investing activities Cash Provided by (Used in) Investing Activity, Including Discontinued Operation Equity Awards Adjustments, Excluding Value Reported in Compensation Table Equity Awards Adjustments, Excluding Value Reported in the Compensation Table [Member] Preferred stock outstanding (in shares) Preferred Stock, Shares Outstanding Aggregate principal amount Debt Instrument, Face Amount 2028 Lessee, Operating Lease, Liability, to be Paid, Year Two Security Exchange Name Security Exchange Name Expected volatility of peer companies, minimum Share-Based Compensation Arrangement by Share-Based Payment Award, Fair Value Assumptions, Expected Volatility Rate Peer Companies, Minimum Share-Based Compensation Arrangement by Share-Based Payment Award, Fair Value Assumptions, Expected Volatility Rate Peer Companies, Minimum Third Amendment Term Loan Third Amendment Term Loan [Member] Third Amendment Term Loan Purchases of marketable securities Payments to Acquire Marketable Securities Accumulated other comprehensive income Accumulated Other Comprehensive Income (Loss), Net of Tax Entity Shell Company Entity Shell Company Operating lease liabilities, current portion Operating Lease, Liability, Current Schedule of Accounts Receivable and Allowance for Credit Losses Accounts Receivable, Allowance for Credit Loss [Table Text Block] Segments Segment Reporting, Policy [Policy Text Block] Schedule of Property and Equipment, Net Property, Plant, and Equipment [Table Text Block] Marketable Securities [Table] Marketable Securities [Table] Net Loss Per Share of Common Stock Earnings Per Share [Text Block] Name Outstanding Recovery, Individual Name Earnings Per Share [Abstract] Earnings Per Share [Abstract] Award Timing, How MNPI Considered Award Timing, How MNPI Considered [Text Block] Document Fiscal Period Focus Document Fiscal Period Focus Peer Group Issuers, Footnote Peer Group Issuers, Footnote [Text Block] TOTAL LIABILITIES Liabilities Trading Symbol Trading Symbol Aggregate Fair Value Debt Securities, Available-for-Sale, Excluding Accrued Interest Geographical [Domain] Geographical [Domain] Purchases of property and equipment Payments to Acquire Property, Plant, and Equipment Prior Year End Fair Value of Equity Awards Granted in Any Prior Year that Fail to Meet Applicable Vesting Conditions During Covered Year Prior Year End Fair Value of Equity Awards Granted in Any Prior Year that Fail to Meet Applicable Vesting Conditions During Covered Year [Member] Pension Adjustments Prior Service Cost Pension Adjustments Prior Service Cost [Member] Unrecognized compensation cost, stock options Share-Based Payment Arrangement, Nonvested Award, Option, Cost Not yet Recognized, Amount Company Selected Measure Name Company Selected Measure Name Income Tax Disclosure [Abstract] Income Tax Disclosure [Abstract] Warrants Issued 3/1/2017 Warrants Issued March First Twenty Seventeen [Member] Warrants Issued March First Twenty Seventeen [Member] Supplemental disclosure of non-cash information Noncash Investing and Financing Items [Abstract] Prepayment fee as percentage of aggregate principal amount Debt Instrument, Fee Amount As Percentage Of Aggregate Principal Debt Instrument, Fee Amount As Percentage Of Aggregate Principal Principal outstanding Total principal payments Long-Term Debt, Gross Final payment fee, percentage Line of Credit Facility, Commitment Fee Percentage Credit Facility [Domain] Credit Facility [Domain] Instrument trays Instrument Trays [Member] Instrument Trays Cash flows from operating activities Cash Provided by (Used in) Operating Activity, Including Discontinued Operation [Abstract] Compensation Amount Outstanding Recovery Compensation Amount Individual: Individual [Axis] Weighted-average number of common shares used to compute diluted net loss per share (in shares) Weighted-average shares used to compute diluted net loss per share (in shares) Weighted Average Number of Shares Outstanding, Diluted Disaggregation of Revenue [Line Items] Disaggregation of Revenue [Line Items] Entity Emerging Growth Company Entity Emerging Growth Company Equity Valuation Assumption Difference, Footnote Equity Valuation Assumption Difference, Footnote [Text Block] Underlying Security Market Price Change Underlying Security Market Price Change, Percent Commercial paper Commercial Paper [Member] U.S. treasury securities U.S. treasury securities US Treasury Securities [Member] Less: imputed interest and tenant improvement allowance Lessee, Operating Lease, Liability, Undiscounted Excess Amount Schedule of Share-based Compensation Arrangements by Share-based Payment Award [Table] Schedule of Share-Based Compensation Arrangements by Share-Based Payment Award [Table] Gross profit Gross Profit Cash paid for amounts included in the measurement of operating lease liabilities Operating Lease, Payments Award Timing Predetermined Award Timing Predetermined [Flag] Adjustment To PEO Compensation, Footnote Adjustment To PEO Compensation, Footnote [Text Block] Stock-based compensation APIC, Share-Based Payment Arrangement, Increase for Cost Recognition Level 1 Fair Value, Inputs, Level 1 [Member] Organization, Consolidation and Presentation of Financial Statements [Abstract] Organization, Consolidation and Presentation of Financial Statements [Abstract] Total operating lease payments Lessee, Operating Lease, Liability, to be Paid Outstanding, beginning of period (in dollars per share) Outstanding, end of period (in dollars per share) Share-Based Compensation Arrangement by Share-Based Payment Award, Equity Instruments Other than Options, Nonvested, Weighted Average Grant Date Fair Value All Executive Categories All Executive Categories [Member] Pension Adjustments Service Cost Pension Adjustments Service Cost [Member] Other comprehensive income (loss): Other Comprehensive Income (Loss), Net of Tax, Portion Attributable to Parent [Abstract] Preferred stock, par value (in dollars per share) Preferred Stock, Par or Stated Value Per Share Class of Warrant or Right [Line Items] Class of Warrant or Right [Line Items] Depreciation expense Depreciation Plan Name [Domain] Plan Name [Domain] Antidilutive Securities [Axis] Antidilutive Securities [Axis] Share-Based Compensation Arrangement by Share-Based Payment Award, Non-Option Equity Instruments, Outstanding [Roll Forward] Share-Based Compensation Arrangement by Share-Based Payment Award, Non-Option Equity Instruments, Outstanding [Roll Forward] Outstanding, beginning of period (in dollars per share) Outstanding, end of period (in dollars per share) Share-Based Compensation Arrangement by Share-Based Payment Award, Options, Outstanding, Weighted Average Exercise Price Sales and marketing Selling and Marketing Expense Operating lease right-of-use assets Operating Lease, Right-of-Use Asset Extended term Lessee, Operating Lease, Renewal Term Schedule of Computation of Basic and Diluted Net Loss per Share Schedule of Earnings Per Share, Basic and Diluted [Table Text Block] Fair Value Disclosures [Abstract] Fair Value Disclosures [Abstract] Risk-free interest rate, maximum Share-Based Compensation Arrangement by Share-Based Payment Award, Fair Value Assumptions, Risk Free Interest Rate, Maximum Debt Disclosure [Abstract] Debt Disclosure [Abstract] Debt Instrument, Name [Domain] Debt Instrument, Name [Domain] Marketable Securities Investment in Debt and Equity Securities and Other Trading Assets [Text Block] Minimum Minimum [Member] Expiration Date Trading Arrangement Expiration Date 2030 Long-Term Debt, Maturity, Year Four Total marketable securities Investments, Fair Value Disclosure Class of Warrant or Right [Axis] Class of Warrant or Right [Axis] Effect of exchange rate changes on cash and cash equivalents Effect of Exchange Rate on Cash, Cash Equivalent, Restricted Cash, and Restricted Cash Equivalent, Continuing Operation Income Statement Location [Axis] Location, Statement of Income, Balance [Axis] Non-Rule 10b5-1 Arrangement Adopted Non-Rule 10b5-1 Arrangement Adopted [Flag] Money market funds Cash and Cash Equivalents, Fair Value Disclosure Weighted-average remaining contractual life, options outstanding Share-Based Compensation Arrangement by Share-Based Payment Award, Options, Outstanding, Weighted-Average Remaining Contractual Term Aggregate Grant Date Fair Value of Equity Award Amounts Reported in Summary Compensation Table Aggregate Grant Date Fair Value of Equity Award Amounts Reported in Summary Compensation Table [Member] Aggregate Pension Adjustments Service Cost Aggregate Pension Adjustments Service Cost [Member] Interest and other income (expense), net: Other Income and Expenses [Abstract] Common stock authorized (in shares) Common Stock, Shares Authorized Schedule of Antidilutive Securities Excluded from Computation of Earnings Per Share [Table] Antidilutive Security, Excluded EPS Calculation [Table] Aggregate intrinsic value, options vested and exercisable Share-Based Compensation Arrangement by Share-Based Payment Award, Options, Vested and Expected to Vest, Exercisable, Aggregate Intrinsic Value Schedule of Restricted Stock Unit Activity Share-Based Payment Arrangement, Restricted Stock Unit, Activity [Table Text Block] Exercise Price Award Exercise Price Cash flows from investing activities Cash Provided by (Used in) Investing Activity, Including Discontinued Operation [Abstract] Document Quarterly Report Document Quarterly Report Year-over-Year Change in Fair Value of Equity Awards Granted in Prior Years That are Outstanding and Unvested Year-over-Year Change in Fair Value of Equity Awards Granted in Prior Years That are Outstanding and Unvested [Member] Accrued Liabilities and Other Accrued Liabilities, Current [Abstract] Prepayment fee, threshold period following closing Debt Instrument, Fee, Threshold Period Following Closing Debt Instrument, Fee, Threshold Period Following Closing Borrowings Debt Disclosure [Text Block] Schedule of Marketable Securities Marketable Securities [Table Text Block] Less: Unamortized debt issuance costs and lender fees Debt Issuance Costs, Net Awards Close in Time to MNPI Disclosures, Table Awards Close in Time to MNPI Disclosures [Table Text Block] First Amendment Term Loan First Amendment Term Loan [Member] First Amendment Term Loan Lease Contractual Term [Axis] Lease Contractual Term [Axis] Equity Component [Domain] Equity Component [Domain] PEO Actually Paid Compensation Amount PEO Actually Paid Compensation Amount Term loan Secured Debt [Member] Adoption Date Trading Arrangement Adoption Date TOTAL STOCKHOLDERS’ EQUITY Stockholders' equity, beginning of period Stockholders' equity, end of period Equity, Attributable to Parent San Jose 102-Month Lease San Jose 102-Month Lease [Member] San Jose 102-Month Lease ASSETS Assets [Abstract] Title Trading Arrangement, Individual Title Forgone Recovery due to Disqualification of Tax Benefits, Amount Forgone Recovery due to Disqualification of Tax Benefits, Amount Accounting Policies [Abstract] Accounting Policies [Abstract] Restatement does not require Recovery Restatement Does Not Require Recovery [Text Block] Total operating lease liabilities Operating Lease, Liability Insider Trading Policies and Procedures [Line Items] Outstanding, beginning of period (in shares) Outstanding, end of period (in shares) Share-Based Compensation Arrangement by Share-Based Payment Award, Options, Outstanding, Number Allowance for doubtful accounts Accounts Receivable, Allowance for Credit Loss, Current Insider Trading Policies and Procedures Adopted Insider Trading Policies and Procedures Adopted [Flag] Laura A. Francis, Trading Arrangement, Performance Based Restricted Stock Units [Member] Laura A. Francis, Trading Arrangement, Performance Based Restricted Stock Units PSUs Performance Shares [Member] Prepaid expenses and other current assets Prepaid Expense and Other Assets, Current Balance Sheet Components Supplemental Balance Sheet Disclosures [Text Block] Canceled and forfeited (in dollars per share) Share-Based Compensation Arrangement by Share-Based Payment Award, Options, Forfeitures and Expirations in Period, Weighted Average Exercise Price Commitments and Contingencies Commitments and Contingencies Disclosure [Text Block] Compensation Actually Paid vs. Net Income Compensation Actually Paid vs. Net Income [Text Block] Common stock equivalents excluded from computation of diluted net loss per share (in shares) Antidilutive Securities Excluded from Computation of Earnings Per Share, Amount Liability associated with indemnifications Estimated Litigation Liability Number of operating segments Number of Operating Segments RSUs Restricted stock units Restricted Stock Units (RSUs) [Member] Schedule of Anti-dilutive Common Stock Equivalents Excluded from Computation of Diluted Net Loss per Share Schedule of Antidilutive Securities Excluded from Computation of Earnings Per Share [Table Text Block] Entity Central Index Key Entity Central Index Key Less: Accumulated depreciation and amortization Property, Plant, and Equipment, Accumulated Depreciation, Depletion, and Amortization Area leased Lease, Operating Lease, Area Leased Lease, Operating Lease, Area Leased All Adjustments to Compensation All Adjustments to Compensation [Member] Dividends or Other Earnings Paid on Equity Awards not Otherwise Reflected in Total Compensation for Covered Year Dividends or Other Earnings Paid on Equity Awards not Otherwise Reflected in Total Compensation for Covered Year [Member] Net cash used in operating activities Cash Provided by (Used in) Operating Activity, Including Discontinued Operation Remainder of 2026 Long-Term Debt, Maturity, Remainder of Fiscal Year Indemnification Agreement Indemnification Agreement [Member] Income Statement [Abstract] Income Statement [Abstract] STOCKHOLDERS’ EQUITY Equity, Attributable to Parent [Abstract] Issuance of common stock related to employee stock purchase plan (in shares) Stock Issued During Period, Shares, Employee Stock Purchase Plans Document Transition Report Document Transition Report Fair Value Hierarchy and NAV [Axis] Fair Value Hierarchy and NAV [Axis] Accrued compensation and related expenses for employee payroll deductions Other Employee-related Liabilities, Current Operating expenses: Operating Expenses [Abstract] Stock Appreciation Rights (SARs) Stock Appreciation Rights (SARs) [Member] Number of Shares Share-Based Compensation Arrangement by Share-Based Payment Award, Options, Outstanding [Roll Forward] Basis spread on variable rate Debt Instrument, Basis Spread on Variable Rate City Area Code City Area Code Accumulated Other Comprehensive Income AOCI Attributable to Parent [Member] All Individuals All Individuals [Member] Schedule of Revenue by Geography Segment Reporting, Entity-Wide Information Not Provided as Part of Reportable Segment, Geographical Area, Revenue [Table Text Block] Name Forgone Recovery, Individual Name Non-GAAP Measure Description Non-GAAP Measure Description [Text Block] Weighted Average Grant Date Fair Value Share-Based Compensation Arrangement by Share-Based Payment Award, Equity Instruments Other than Options, Nonvested, Weighted Average Grant Date Fair Value [Abstract] Total marketable securities, unrealized gains Cash, Cash Equivalents, and Short-Term Investments, Accumulated Gross Unrealized Gain, Before Tax Cash, Cash Equivalents, and Short-Term Investments, Accumulated Gross Unrealized Gain, Before Tax Statement [Line Items] Statement [Line Items] TOTAL ASSETS Assets Preferred stock issued (in shares) Preferred Stock, Shares Issued Net unrealized loss on marketable securities OCI, Debt Securities, Available-for-Sale, Gain (Loss), before Adjustment, after Tax Interest expense Interest Expense, Nonoperating Unrealized Gains Debt Securities, Available-for-Sale, Accumulated Gross Unrealized Gain, before Tax Stock-Based Incentive Compensation Plans Share-Based Payment Arrangement [Text Block] Issuance of common stock related to employee stock purchase plan Stock Issued During Period, Value, Employee Stock Purchase Plan The Company and Nature of Business Nature of Operations [Text Block] PEO PEO [Member] 2028 Long-Term Debt, Maturity, Year Two Cash and Cash Equivalents [Domain] Cash and Cash Equivalents [Domain] Expected reimbursement, tenant improvements Operating Lease, Expected Reimbursement, Tenant Improvements Operating Lease, Expected Reimbursement, Tenant Improvements Stock-based compensation expense Share-Based Payment Arrangement, Expense Correlation coefficient of peer companies, minimum Share-Based Compensation Arrangement by Share-Based Payment Award, Fair Value Assumptions, Correlation Coefficient Of Peer Companies, Minimum Share-Based Compensation Arrangement by Share-Based Payment Award, Fair Value Assumptions, Correlation Coefficient Of Peer Companies, Minimum Forgone Recovery due to Violation of Home Country Law, Amount Forgone Recovery due to Violation of Home Country Law, Amount Issuance of common stock upon exercise of stock options, net of shares withheld (in shares) Exercised (in shares) Share-Based Compensation Arrangement by Share-Based Payment Award, Options, Exercises in Period Granted (in dollars per share) Share-Based Compensation Arrangement by Share-Based Payment Award, Equity Instruments Other than Options, Grants in Period, Weighted Average Grant Date Fair Value Amortized Cost Cash Equivalents, at Carrying Value Subsequent Event Type [Domain] Subsequent Event Type [Domain] Accumulated Deficit Retained Earnings [Member] Operating lease liabilities, net of current portion Operating Lease, Liability, Noncurrent Debt Securities, Available-for-Sale, Accrued Interest, after Allowance for Credit Loss, Statement of Financial Position [Extensible Enumeration] Debt Securities, Available-for-Sale, Accrued Interest, after Allowance for Credit Loss, Statement of Financial Position [Extensible Enumeration] Total operating expenses Operating Expenses Revolving credit facility Revolving Credit Facility [Member] Money market funds Money Market Funds [Member] Canceled and forfeited (in dollars per share) Share-Based Compensation Arrangement by Share-Based Payment Award, Equity Instruments Other than Options, Forfeitures, Weighted Average Grant Date Fair Value Erroneously Awarded Compensation Recovery Erroneously Awarded Compensation Recovery [Table] Increase (Decrease) in Stockholders' Equity [Roll Forward] Increase (Decrease) in Stockholders' Equity [Roll Forward] Common stock outstanding (in shares) Stockholders' equity, beginning of period (in shares) Stockholders' equity, end of period (in shares) Common Stock, Shares, Outstanding Award Timing Disclosures [Line Items] Net loss per share, diluted (in dollars per share) Earnings Per Share, Diluted Entity Current Reporting Status Entity Current Reporting Status Net cash provided by financing activities Cash Provided by (Used in) Financing Activity, Including Discontinued Operation Expected volatility of common stock, maximum Share-Based Compensation Arrangement by Share-Based Payment Award, Fair Value Assumptions, Expected Volatility Rate, Maximum Total Shareholder Return Amount Total Shareholder Return Amount Prepaid expenses and other assets Increase (Decrease) in Prepaid Expense and Other Assets Research and development Research and Development Expense Lease Contractual Term [Domain] Lease Contractual Term [Domain] 2029 Long-Term Debt, Maturity, Year Three Write-offs Accounts Receivable, Allowance for Credit Loss, Writeoff Loss Contingency Nature [Axis] Loss Contingency Nature [Axis] Disclosure of Compensation Related Costs, Share-based Payments [Abstract] Share-Based Payment Arrangement [Abstract] Cash flows from financing activities Cash Provided by (Used in) Financing Activity, Including Discontinued Operation [Abstract] Revenue Revenue from Contract with Customer, Excluding Assessed Tax Property and equipment, net Property and equipment, net Property, Plant, and Equipment, after Accumulated Depreciation, Depletion, and Amortization Thereafter Lessee, Operating Lease, Liability, to be Paid, After Year Four Lessee, Operating Lease, Liability, to be Paid, After Year Four Financial Instruments [Domain] Financial Instruments [Domain] Options vested and exercisable (in shares) Share-Based Compensation Arrangement by Share-Based Payment Award, Options, Vested and Expected to Vest, Exercisable, Number Issuance of common stock upon exercise of stock options, net of shares withheld Stock Issued During Period, Value, Stock Options Exercised Equity Awards Adjustments, Footnote Equity Awards Adjustments, Footnote [Text Block] Underlying Securities Award Underlying Securities Amount Maturities of marketable securities Proceeds From Maturity Of Marketable Securities Proceeds From Maturity Of Marketable Securities Options vested and exercisable (in dollars per share) Share-Based Compensation Arrangement by Share-Based Payment Award, Options, Vested and Expected to Vest, Exercisable, Weighted Average Exercise Price Construction in progress Construction in Progress [Member] Inventory Increase (Decrease) in Inventories Laura A. Francis, Trading Arrangement, Common Stock [Member] Michael Pisetsky, Trading Arrangement, Common Stock Weighted average discount rate Operating Lease, Weighted Average Discount Rate, Percent Risk-free interest rate, minimum Share-Based Compensation Arrangement by Share-Based Payment Award, Fair Value Assumptions, Risk Free Interest Rate, Minimum Schedule of Future Principal and Final Fee Payments Schedule of Maturities of Long-Term Debt [Table Text Block] Weighted-Average Remaining Contractual Life and Aggregate Intrinsic Value Share-Based Compensation Arrangement by Share-Based Payment Award, Options, Additional Disclosures [Abstract] Summary of Information Related to Lease Expense and Valuation of Lease Assets and Lease Liabilities Lease, Cost [Table Text Block] Commitments and Contingencies Disclosure [Abstract] Commitments and Contingencies Disclosure [Abstract] All Trading Arrangements All Trading Arrangements [Member] Other Performance Measure, Amount Other Performance Measure, Amount Award Timing MNPI Considered Award Timing MNPI Considered [Flag] Owen Lease Owen Lease [Member] Owen Lease Loss from operations Operating Income (Loss) Current Fiscal Year End Date Current Fiscal Year End Date Non-PEO NEO Average Total Compensation Amount Non-PEO NEO Average Total Compensation Amount Operating lease liabilities not commenced Unrecorded Unconditional Purchase Obligation Change in Fair Value as of Vesting Date of Prior Year Equity Awards Vested in Covered Year Change in Fair Value as of Vesting Date of Prior Year Equity Awards Vested in Covered Year [Member] Entity File Number Entity File Number Rule 10b5-1 Arrangement Adopted Rule 10b5-1 Arrangement Adopted [Flag] Schedule of Warrants Issued and Outstanding Schedule of Stockholders' Equity Note, Warrants or Rights [Table Text Block] SVB Term Loan SVB Term Loan [Member] SVB Term Loan Schedule of Stock Option Activity Share-Based Payment Arrangement, Option, Activity [Table Text Block] Weighted- Average Exercise Price Share-Based Compensation Arrangement by Share-Based Payment Award, Options, Outstanding, Weighted Average Exercise Price [Abstract] Recovery of Erroneously Awarded Compensation Disclosure [Line Items] Antidilutive Securities Excluded from Computation of Earnings Per Share [Line Items] Antidilutive Securities Excluded from Computation of Earnings Per Share [Line Items] Common stock issued (in shares) Common Stock, Shares, Issued Measure: Measure [Axis] Inventory, finished goods, gross Inventory, Finished Goods, Gross Employee stock purchase program offering period interval (in months) Share-Based Compensation Arrangement By Share-Based Payment Award, Offering Period Interval Share-Based Compensation Arrangement By Share-Based Payment Award, Offering Period Interval Accrued royalty Accrued Royalties, Current Equity Components [Axis] Equity Components [Axis] Accounts receivable Increase (Decrease) in Accounts Receivable 2018 ESPP 2018 Employee Stock Purchase Plan [Member] A2018 Employee Stock Purchase Plan [Member] Computer and office equipment Computer And Office Equipment [Member] Computer And Office Equipment [Member] Disaggregation of Revenue [Table] Disaggregation of Revenue [Table] Entity Interactive Data Current Entity Interactive Data Current Compensation Actually Paid vs. Other Measure Compensation Actually Paid vs. Other Measure [Text Block] Entity Small Business Entity Small Business Comprehensive loss Comprehensive Income (Loss), Net of Tax, Attributable to Parent 2029 Lessee, Operating Lease, Liability, to be Paid, Year Three Termination Date Trading Arrangement Termination Date First-Citizens Term Loan First-Citizens Term Loan [Member] First-Citizens Term Loan Property, Plant, and Equipment [Line Items] Property and Equipment, Net Property, Plant, and Equipment [Line Items] Fair Value Measurements, Recurring and Nonrecurring [Table] Fair Value, Recurring and Nonrecurring [Table] Compensation Actually Paid vs. Total Shareholder Return Compensation Actually Paid vs. Total Shareholder Return [Text Block] MNPI Disclosure Timed for Compensation Value MNPI Disclosure Timed for Compensation Value [Flag] Other non-current assets Other Assets, Noncurrent Document Type Document Type Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] Accrued liabilities and other Accrued liabilities and other Accrued Liabilities, Current El Camino Lease El Camino Lease [Member] El Camino Lease Fair Value as of Grant Date Award Grant Date Fair Value Credit losses on investments Debt Securities, Available-for-Sale, Allowance for Credit Loss, Excluding Accrued Interest Summary of Significant Accounting Policies Significant Accounting Policies [Text Block] Pay vs Performance Disclosure, Table Pay vs Performance [Table Text Block] Arrangement Duration Trading Arrangement Duration Statement of Stockholders' Equity [Abstract] Statement of Stockholders' Equity [Abstract] Local Phone Number Local Phone Number Inventory, work in process, gross Inventory, Work in Process, Gross Entity Address, Postal Zip Code Entity Address, Postal Zip Code Entity Registrant Name Entity Registrant Name Black-Scholes option-pricing model assumptions Share-Based Compensation Arrangement by Share-Based Payment Award, Fair Value Assumptions and Methodology [Abstract] Monthly base rent Lessee, Operating Lease, Monthly Base Rent Lessee, Operating Lease, Monthly Base Rent Schedule of Performance-based Restricted Stock Unit Activity Arrangement Share-Based Payment Arrangement, Performance Shares, Activity [Table Text Block] Insider Trading Policies and Procedures Not Adopted Insider Trading Policies and Procedures Not Adopted [Text Block] Aggregate intrinsic value, options vested and expected to vest Share-Based Compensation Arrangement by Share-Based Payment Award, Options, Vested and Expected to Vest, Outstanding, Aggregate Intrinsic Value Commitments and contingencies (Note 6) Commitments and Contingencies Antidilutive Securities, Name [Domain] Antidilutive Securities, Name [Domain] Property and equipment, gross Property, Plant, and Equipment, before Accumulated Depreciation, Depletion, and Amortization Changed Peer Group, Footnote Changed Peer Group, Footnote [Text Block] Machinery and equipment Machinery and Equipment [Member] Forgone Recovery due to Expense of Enforcement, Amount Forgone Recovery due to Expense of Enforcement, Amount Executive Category: Executive Category [Axis] Accrued interest writeoff Debt Securities, Available-for-Sale, Accrued Interest Writeoff Performance period Share-Based Compensation Arrangement by Share-Based Payment Award, Award Vesting Period Furniture and fixtures Furniture and Fixtures [Member] LIABILITIES AND STOCKHOLDERS’ EQUITY Liabilities and Equity [Abstract] Correlation coefficient of peer companies, maximum Share-Based Compensation Arrangement by 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Schedule of Marketable Securities Measured at Fair Value on Recurring Basis Schedule of Fair Value, Assets and Liabilities Measured on Recurring Basis [Table Text Block] Inventory Inventory, Net Equity Award [Domain] Award Type [Domain] Non-PEO NEO Average Compensation Actually Paid Amount Non-PEO NEO Average Compensation Actually Paid Amount Warrants outstanding, beginning balance (in shares) Warrants outstanding, ending balance (in shares) Class of Warrant or Right, Outstanding Remainder of 2026 Lessee, Operating Lease, Liability, to be Paid, Remainder of Fiscal Year Fair Value Measurement Fair Value Disclosures [Text Block] Level 3 Fair Value, Inputs, Level 3 [Member] U.S. agency bonds US Government Agencies Debt Securities [Member] Weighted-average remaining contractual life, options vested and exercisable Share-Based Compensation Arrangement by Share-Based Payment Award, Options, Vested and Expected to Vest, Exercisable, Weighted-Average Remaining Contractual Term Operating lease 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