Share-based Compensation Arrangement by Share-based Payment Award, Equity Instruments Other than Options, Nonvested, Number of Shares [Roll Forward] Granted Share-based Compensation Arrangement by Share-based Payment Award, Equity Instruments Other than Options, Grants in Period, Weighted Average Grant Date Fair Value Unvested, beginning balance Unvested, ending balance Share-based Compensation Arrangement by Share-based Payment Award, Equity Instruments Other than Options, Nonvested, Weighted Average Grant Date Fair Value 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] Accrued Leasehold Improvements Accrued Leasehold Improvements Common stock, $0.0001 par value Preferred stock, $0.0001 par value Other Assets [Member] Balance Sheet Location [Domain] Balance Sheet Location [Axis] Manufacturing Agreement Expense Manufacturing Agreement Expense Plan description Long-Term Performance Incentive Plan Description Long-Term Performance Incentive Plan Description Sales Sales Forecasting Sales Forecasting Stock Price Sale of Stock, Price Per Share Consecutive Trading days Consecutive Trading Days Consecutive Trading Days Performance Periods Share Based Compensation Arrangement By Share Based Payment Award Options performance period Share Based Compensation Arrangement By Share Based Payment Award Options performance period 2021 LTPIP Two Thousand Twenty One Long-Term Performance Incentive Plan [Member] Two Thousand Twenty One Long-Term Performance Incentive Plan [Member] Increase (Decrease) in Accounts Payable, Total Cash, Cash Equivalents, Restricted Cash and Restricted Cash Equivalents, Including Disposal Group and Discontinued Operations, Total Other Liabilities, Noncurrent, Total Interest Expense, Total Operating Lease, Liability, Total Cash and Cash Equivalents, at Carrying Value, Ending Balance Cash and Cash Equivalents, at Carrying Value, Beginning Balance Cash and Cash Equivalents, at Carrying Value, Total Payments to Acquire Property, Plant, and Equipment, Total Debt Securities, Available-for-sale, Current, Total APIC, Share-based Payment Arrangement, Increase for Cost Recognition, Total Earnings Per Share, Basic and Diluted, Total Payments to Acquire Marketable Securities, Total Employee-related Liabilities, Current, Total Share-based Compensation Arrangement by Share-based Payment Award, Options, Forfeitures and Expirations in Period, Total Debt Securities, Available-for-sale, Allowance for Credit Loss, Ending Balance Debt Securities, Available-for-sale, Allowance for Credit Loss, Beginning Balance Debt Securities, Available-for-sale, Allowance for Credit Loss, Total Income Statement Location [Axis] Schedule Of Employee Service Share Based Compensation Allocation Of Recognized Period Costs [Table] Schedule Of Employee Service Share Based Compensation Allocation Of Recognized Period Costs [Table] Stock based compensation expense related to ESPP Stock Issued During Period Value Employee Stock Purchase Plan Common stock purchase price percentage Sharebased Compensation Arrangement By Sharebased Payment Award Purchase Price Of Common Stock Percent Common stock, shares reserved for issuance Common Stock Capital Shares Reserved For Future Issuance Number of purchase periods Number Of Purchase Periods Number of purchase periods. Term of offering period Term Of Offering Period Term of offering period. Total stock-based compensation Stock-based compensation expense recognized Allocated Share Based Compensation Expense Awards vested Share Based Compensation Arrangement By Share Based Payment Award Equity Instruments Other Than Options Vested In Period Vesting period for achievement of specific milestone Share Based Compensation Arrangement By Share Based Payment Award Vesting Period For Achievement Of Specific Milestone Share based compensation arrangement by share based payment award vesting period for achievement of specific milestone. Unvested Restricted Shares Restricted Shares Performance expiration date Share Based Compensation Arrangement By Share Based Payment Award Options Performance Period Expiration Share based compensation arrangement by share based payment award options performance period expiration. Canceled Granted Unvested, beginning balance Unvested, ending balance Share-based Compensation Arrangement by Share-based Payment Award, Equity Instruments Other than Options, Forfeited in Period 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, Equity Instruments Other than Options, Nonvested, Number Canceled Share-based Compensation Arrangement by Share-based Payment Award, Equity Instruments Other than Options, Forfeitures, Weighted Average Grant Date Fair Value Vested Share-based Compensation Arrangement by Share-based Payment Award, Equity Instruments Other than Options, Vested in Period, Weighted Average Grant Date Fair Value Restricted Stock [Member] Balance Share Based Compensation Arrangement By Share Based Payment Award Options Outstanding Intrinsic Value Aggregate Intrinsic Value Share Based Compensation Arrangement By Share Based Payment Award Options Aggregate Intrinsic Value [Abstract] Earnings Per Share [Abstract] Stock-Based Compensation Disclosure Of Compensation Related Costs Share Based Payments [Text Block] Disclosure Of Compensation Related Costs Sharebased Payments [Abstract] Commitments and Contingencies Commitments And Contingencies Disclosure [Text Block] Commitments And Contingencies Disclosure [Abstract] Marketable Securities Investments In Debt And Marketable Equity Securities And Certain Trading Assets Disclosure [Text Block] Investments Debt And Equity Securities [Abstract] Fair Value Measurements Fair Value Disclosures [Text Block] Fair Value Disclosures [Abstract] Accrued and Other Current Liabilities Accounts Payable Accrued Liabilities And Other Liabilities Disclosure Current [Text Block] Accounts Payable And Accrued Liabilities Current [Abstract] Summary of Significant Accounting Policies Significant Accounting Policies [Text Block] Accounting Policies [Abstract] Organization Consolidation And Presentation Of Financial Statements [Abstract] The Company The Company [Text Block] The entire disclosure for the company. Purchase of property and equipment under accounts payable and accruals Noncash Or Part Noncash Acquisition Fixed Assets Acquired1 Operating lease right-of-use asset obtained in exchange for operating lease liability Right Of Use Asset Obtained In Exchange For Operating Lease Liability Supplemental disclosures of non-cash investing and financing information: Cash Flow Noncash Investing And Financing Activities Disclosure [Abstract] Reconciliation of cash, cash equivalents and restricted cash to consolidated balance sheets Cash Cash Equivalents Restricted Cash And Restricted Cash Equivalents [Abstract] Cash, cash equivalents and restricted cash, at beginning of period Cash, cash equivalents and restricted cash, at end of period Cash Cash Equivalents Restricted Cash And Restricted Cash Equivalents Including Disposal Group And Discontinued Operations Net increase (decrease) in cash, cash equivalents and restricted cash Cash Cash Equivalents Restricted Cash And Restricted Cash Equivalents Period Increase Decrease Excluding Exchange Rate Effect Net cash provided by financing activities Net Cash Provided By Used In Financing Activities Principal payments of capital lease Repayments Of Debt And Capital Lease Obligations Proceeds from issuance of common stock upon options exercise Proceeds From Stock Options Exercised Cash flows from financing activities Net Cash Provided By Used In Financing Activities [Abstract] Net cash provided by (used in) investing activities Net Cash Provided By Used In Investing Activities Maturities of marketable securities Proceeds From Sale And Maturity Of Marketable Securities Purchase of marketable securities Payments To Acquire Marketable Securities Purchase of property and equipment Payments To Acquire Property Plant And Equipment Cash flows from investing activities Net Cash Provided By Used In Investing Activities [Abstract] Net cash used in operating activities Accounts Payable, Current, Total General and Administrative Expense, Total Preferred Stock, Shares Issued, Total Other Comprehensive Income (Loss), Available-for-sale Securities Adjustment, Net of Tax, Portion Attributable to Parent, Total Other Nonoperating Income (Expense), Total Preferred Stock, Value, Issued, Beginning Balance Preferred Stock, Value, Issued, Total Common Stock, Shares, Issued, Total Research and Development Expense, Total Other-than-temporary Impairment Loss, Debt Securities, Available-for-sale, Total Common Stock, Value, Issued, Ending Balance Common Stock, Value, Issued, Beginning Balance Common Stock, Value, Issued, Total Increase (Decrease) in Prepaid Expense and Other Assets, Total Depreciation, Total Property, Plant and Equipment, Net, Ending Balance Preferred Stock, Shares Outstanding, Ending Balance Preferred Stock, Shares Outstanding, Beginning Balance Increase (Decrease) in Other Operating Assets, Total Proceeds from Sale and Maturity of Marketable Securities, Total Subsequent Event [Line Items] Subsequent Event [Line Items] Subsequent Event Subsequent Event [Member] Subsequent Event Type Subsequent Event Type [Domain] Subsequent Event Type Subsequent Event Type [Axis] Subsequent Event [Table] Subsequent Event [Table] Anti-dilutive securities excluded from the computation of diluted net loss per common share Antidilutive Securities Excluded From Computation Of Earnings Per Share Amount Antidilutive Securities Excluded From Computation Of Earnings Per Share [Line Items] Antidilutive Securities Excluded From Computation Of Earnings Per Share [Line Items] Outstanding Stock Options Employee Stock Option [Member] Antidilutive Securities, Name Antidilutive Securities Name [Domain] Antidilutive Securities Antidilutive Securities Excluded From Computation Of Earnings Per Share By Antidilutive Securities [Axis] Schedule Of Antidilutive Securities Excluded From Computation Of Earnings Per Share [Table] Schedule Of Antidilutive Securities Excluded From Computation Of Earnings Per Share [Table] Unrecognized compensation weighted-average period expected for recognition Employee Service Share Based Compensation Nonvested Awards Total Compensation Cost Not Yet Recognized Period For Recognition1 Unrecognized compensation cost related to unvested share based awards Employee Service Share Based Compensation Nonvested Awards Total Compensation Cost Not Yet Recognized Stock Options Employee Service Share Based Compensation Allocation Of Recognized Period Costs [Line Items] Employee Service Share Based Compensation Allocation Of Recognized Period Costs [Line Items] General and Administrative General And Administrative Expense [Member] Research and Development Research And Development Expense [Member] Income Statement Location Income Statement Location [Domain] Income Statement Location Property, Plant and Equipment, Net, Beginning Balance Property, Plant and Equipment, Net, Total Loss from operations Debt Securities, Available-for-sale, Total Additional Paid in Capital, Common Stock, Ending Balance Additional Paid in Capital, Common Stock, Beginning Balance Operating lease liability, net of current portion Operating Lease Liability Noncurrent Share-based compensation arrangement by share-based payment award, options, aggregate intrinsic value. Weighted Average Remaining Contractual Term (in years) Sharebased Compensation Arrangement By Sharebased Payment Award Options Outstanding Weighted Average Remaining Contractual Term2 Weighted Average Remaining Contractual Term (in years) Share Based Compensation Arrangement By Share Based Payment Award Options Weighted Average Remaining Contractual Term [Abstract] Share-based compensation arrangement by share-based payment award, options, weighted average remaining contractual term. Forfeited or canceled Share Based Compensation Arrangement By Share Based Payment Award Options Forfeitures And Expirations In Period Weighted Average Exercise Price Exercised Share Based Compensation Arrangements By Share Based Payment Award Options Exercises In Period Weighted Average Exercise Price Granted Share Based Compensation Arrangements By Share Based Payment Award Options Grants In Period Weighted Average Exercise Price Beginning balance Ending balance Share Based Compensation Arrangement By Share Based Payment Award Options Outstanding Weighted Average Exercise Price Weighted Average Exercise Price Share Based Compensation Arrangement By Share Based Payment Award Options Outstanding Weighted Average Exercise Price Rollforward Forfeited or canceled Share Based Compensation Arrangement By Share Based Payment Award Options Forfeitures And Expirations In Period Stock options, granted Granted Share Based Compensation Arrangement By Share Based Payment Award Options Grants In Period Gross Beginning balance Ending balance Share Based Compensation Arrangement By Share Based Payment Award Options Outstanding Number Number of Options Share Based Compensation Arrangement By Share Based Payment Award Options Outstanding Roll Forward 2018 Plan and 2015 Equity Incentive Plan Two Thousand Eighteen And Two Thousand Fifteen Equity Incentive Plan [Member] Two thousand eighteen and two thousand fifteen equity incentive plan. Number of common stock available for issuance increased Share Based Compensation Arrangement By Share Based Payment Award Number Of Additional Shares Authorized Share Based Compensation Arrangement By Share Based Payment Award [Line Items] Share Based Compensation Arrangement By Share Based Payment Award [Line Items] 2018 Employee Share Purchase Plan Two Thousand Eighteen Employee Share Purchase Plan [Member] Two thousand eighteen employee share purchase plan. Performance Based Equity Awards Performance Based Equity Awards [Member] Performance based equity awards. Performance-based Stock Options Performance Based Stock Options [Member] Performance-based stock options. Award Type Share Based Compensation Arrangements By Share Based Payment Award Award Type And Plan Name [Domain] Award Type Award Type [Axis] 2018 Equity Incentive Plan Two Thousand Eighteen Equity Incentive Plan [Member] Two thousand eighteen equity incentive plan. Plan Name Plan Name [Domain] Plan Name Plan Name [Axis] Schedule Of Share Based Compensation Arrangements By Share Based Payment Award [Table] Schedule Of Share Based Compensation Arrangements By Share Based Payment Award [Table] Lease liabilities Operating Lease Liability Annual suite fees payment for 2021 Contractual Obligation Due In Next Twelve Months Lease Agreement Lease Agreements [Member] Finite-Lived Intangible Assets, Major Class Name Finite Lived Intangible Assets Major Class Name [Domain] Finite-Lived Intangible Assets by Major Class Finite Lived Intangible Assets By Major Class [Axis] Lonza Lonza [Member] Lonza. Counterparty Name Repurchase Agreement Counterparty Name [Domain] Counterparty Name Counterparty Name [Axis] Manufacturing Agreement Manufacturing Agreement [Member] Manufacturing agreement. Collaborative Arrangement and Arrangement Other than Collaborative Entity Current Reporting Status Entity Current Reporting Status Entity Registrant Name Entity Registrant Name Trading Symbol Trading Symbol Document Fiscal Period Focus Document Fiscal Period Focus Document Fiscal Year Focus Document Fiscal Year Focus Document Period End Date Document Period End Date Amendment Flag Amendment Flag Document Type Document Type Cover [Abstract] Entity Central Index Key Entity Central Index Key Entity Central Index Key Other liabilities Other Liabilities Noncurrent Fair Value, current Available For Sale Securities Debt Securities Current Marketable Securities [Line Items] Marketable Securities [Line Items] Investments Investment Type Categorization [Member] Investment Type Investment Type [Axis] Marketable Securities [Table] Marketable Securities [Table] Unrealized Losses, current Available For Sale Debt Securities Accumulated Gross Unrealized Loss Before Tax Current Available for sale debt securities accumulated gross unrealized loss before tax current. Unrealized Gains, current Available For Sale Debt Securities Accumulated Gross Unrealized Gain Before Tax Current Available for sale debt securities accumulated gross unrealized gain before tax, current. Amortized Cost, current Available For Sale Debt Securities Amortized Cost Basis Current Available for sale debt securities amortized cost basis current. Total Assets Fair Value Disclosure Retained Earnings (Accumulated Deficit), Ending Balance Retained Earnings (Accumulated Deficit), Beginning Balance Retained Earnings (Accumulated Deficit), Total Debt Securities, Available-for-sale, Realized Gain (Loss), Total Marketable Securities, Current, Total Common Stock, Shares, Outstanding, Ending Balance Common Stock, Shares, Outstanding, Beginning Balance Share-based Payment Arrangement, Noncash Expense, Total Other Assets, Noncurrent, Total Cash, Cash Equivalents, and Short-term Investments, Total Accumulated Other Comprehensive Income (Loss), Net of Tax, Total Preferred Stock, Value, Issued, Ending Balance Marketable securities Available For Sale Securities Debt Securities Cash equivalents Cash And Cash Equivalents Fair Value Disclosure 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] U.S. Treasury Securities U S Treasury Securities [Member] Corporate Notes Corporate Note Securities [Member] Money Market Funds Money Market Funds [Member] Asset Class Fair Value Assets Measured On Recurring Basis Unobservable Input Reconciliation By Asset Class [Domain] Asset Class Fair Value By Asset Class [Axis] Fair Value, Measurements, Recurring Fair Value Measurements Recurring [Member] Measurement Frequency Fair Value Measurement Frequency [Domain] Measurement Frequency Fair Value By Measurement Frequency [Axis] Significant Unobservable Inputs (Level 3) Fair Value Inputs Level3 [Member] Significant Observable Inputs (Level 2) Fair Value Inputs Level2 [Member] Quoted Price in Active Markets (Level 1) Fair Value Inputs Level1 [Member] Fair Value Hierarchy and NAV Fair Value Measurements Fair Value Hierarchy [Domain] Significant Observable Inputs (Level 2) Fair Value By Fair Value Hierarchy Level [Axis] Fair Value Assets And Liabilities Measured On Recurring And Nonrecurring Basis [Table] Fair Value Assets And Liabilities Measured On Recurring And Nonrecurring Basis [Table] Accrued other liabilities Other Accrued Liabilities Current Accrued professional fees Accrued Professional Fees Current Accrued salaries and benefits Employee Related Liabilities Current Accrued legal fees Accrued Legal Fees Current Accrued legal fees current. Accrued research and development Accrued Research And Development Current Accrued research and development current. Accrued clinical trial and related costs Accrued Clinical Trial And Related Costs Current Accrued clinical trial and related costs current. Cash and cash equivalents and marketable securities Cash Cash Equivalents And Short Term Investments Summary of Anti-dilutive Securities Excluded from Computation of Diluted Net Loss per Common Share Schedule Of Antidilutive Securities Excluded From Computation Of Earnings Per Share [Text Block] Summary of Stock-based Compensation for Options and Restricted Shares Classified in Condensed Consolidated Statements of Operations and Comprehensive Loss Schedule Of Compensation Cost For Share Based Payment Arrangements Allocation Of Share Based Compensation Costs By Plan Table [Text Block] Summary of Restricted Shares Schedule Of Sharebased Compensation Restricted Stock And Restricted Stock Units Activity Table [Text Block] Summary of Stock Options Activity under 2018 Plan and 2015 Equity Incentive Plan Schedule Of Share Based Compensation Stock Options Activity Table [Text Block] Summary of Marketable Securities Marketable Securities [Text Block] Summary of Fair Value Hierarchy for Assets Measured at Fair Value on Recurring Basis Fair Value Assets Measured On Recurring Basis [Text Block] Schedule of Accrued and Other Current Liabilities Schedule Of Accrued And Other Current Liabilities Table [Text Block] Schedule of accrued and other current liabilities. Recent Accounting Pronouncements New Accounting Pronouncements Policy Policy [Text Block] Risk and Uncertainties Risk And Uncertainties Policy [Text Block] Risk and uncertainties. Use of Estimates Use Of Estimates Reclassification Prior Period Reclassification Adjustment Description Basis of Presentation and Principles of Consolidation Basis Of Accounting Policy Policy [Text Block] Subsequent Events [Text Block] Subsequent Events [Abstract] Net Loss per Common Share Earnings Per Share [Text Block] Total current liabilities Liabilities Current Operating lease liability Operating Lease Liability Current Total accrued and other current liabilities Accrued and other current liabilities Accrued Liabilities Current Accounts payable Accounts Payable Current Current liabilities: Liabilities Current [Abstract] Liabilities and stockholders’ equity Liabilities And Stockholders Equity [Abstract] Total assets Assets Other assets Other Assets Noncurrent Operating lease right-of-use asset Operating Lease Right Of Use Asset Property and equipment, net Property Plant And Equipment Net Restricted cash Restricted Cash Noncurrent Total current assets Assets Current Prepaid expenses and other current assets Prepaid Expense And Other Assets Current Marketable securities Marketable Securities Current Cash and cash equivalents Cash And Cash Equivalents At Carrying Value Current assets: Assets Current [Abstract] Assets Assets [Abstract] Statement Of Financial Position [Abstract] Liability related to sale of future royalties Liability Related To Sale Of Future Royalties Liability related to sale of future royalties. Document Transition Report Document Transition Report Document Quarterly Report Document Quarterly Report Entity Incorporation, State or Country Code Entity Incorporation State Country Code Security Exchange Name Security Exchange Name Title of 12(b) Security Security12b Title Vested Issuance of common stock pursuant to employee stock purchase plans Stock Issued During Period, Shares, Employee Stock Purchase Plans Issuance of common stock pursuant to employee stock purchase plans, shares Payment, Tax Withholding, Share-based Payment Arrangement Payments for restricted stock units, net of taxes withheld Proceeds, Issuance of Shares, Share-based Payment Arrangement, Excluding Option Exercised Proceeds from issuance of common stock pursuant to employee stock purchase plans Arrangements And Nonarrangement Transactions [Member] Collaborative Arrangement and Arrangement Other than Collaborative Type Of Arrangement [Axis] Clinical and Commercial Supply of Drug Substance Clinical And Commercial Supply [Member] Clinical and commercial supply. Long-Lived Tangible Asset Property Plant And Equipment Type [Domain] Long-Lived Tangible Asset Property Plant And Equipment By Type [Axis] Commitments And Contingencies Disclosure [Table] Commitments And Contingencies Disclosure [Table] Commitments and contingencies disclosure. Commitments And Contingencies Disclosure [Line Items] Commitments And Contingencies Disclosure [Line Items] Commitments and contingencies disclosure. Manufacturing agreement term that can be extended Manufacturing Agreement Term That Can Be Extended Manufacturing agreement term that can be extended. Manufacturing agreement initial term Manufacturing Agreement Initial Term Manufacturing agreement initial term. Annual suite fees payment each year after 2021 Contractual Obligation Due In Second Year And After Contractual obligation due in second year and after. Estimated Capital Contributions Estimated capital contributions. Impairment charges or recoveries related to marketable securities Other Than Temporary Impairment Loss Debt Securities Available For Sale Allowance for credit losses for available-for-sale debt securities Debt Securities Available For Sale Allowance For Credit Loss Realized gains or losses recognized on sale or maturity of available-for-sale debt securities Debt Securities Available For Sale Realized Gain Loss Marketable securities, effective maturities Debt Securities Available For Sale Term Minimum Minimum [Member] Maximum Maximum Maximum [Member] Statistical Measurement Range [Member] Statistical Measurement Range [Axis] Net Cash Provided By Used In Operating Activities Accrued and other current liabilities Increase Decrease In Accrued Liabilities And Other Operating Liabilities Accounts payable Increase Decrease In Accounts Payable Other assets Increase Decrease In Other Operating Assets Prepaid expenses and other current assets Increase Decrease In Prepaid Deferred Expense And Other Assets Changes in assets and liabilities: Increase Decrease In Operating Capital [Abstract] Amortization (accretion) of premium (discount) on marketable securities Accretion Amortization Of Discounts And Premiums Investments Stock-based compensation Share Based Compensation Depreciation Depreciation Adjustments to reconcile net loss to net cash used in operating activities: Adjustments To Reconcile Net Income Loss To Cash Provided By Used In Operating Activities [Abstract] Cash flows from operating activities Net Cash Provided By Used In Operating Activities [Abstract] Statement Of Cash Flows [Abstract] Principal payments of tenant improvement allowance payable Principal Payments Of Tenant Improvement Allowance Payable Principal payments of tenant improvement allowance payable. Proceeds from sale of future royalties, net of issuance costs Proceeds From Sale Of Future Royalties Net Of Issuance Costs Proceeds from sale of future royalties, net of issuance costs. Deposits on property and equipment Deposits On Property And Equipment Deposits on property and equipment. Operating lease liability Increase Decrease In Operating Lease Liability Increase decrease in operating lease liability. Amortization of issuance costs Amortization Of Issuance Costs Amortization of issuance costs. Amortization of operating lease right-of-use asset Operating Lease Right Of Use Asset Amortization Operating lease right of use asset amortization. Stock-based compensation expense Adjustments To Additional Paid In Capital Sharebased Compensation Requisite Service Period Recognition Value Issuance of common stock upon exercise of common stock warrant, shares Issuance Of Common Stock Upon Exercise Of Common Stock Warrants Shares Issuance of common stock upon exercise of common stock warrants, shares. Issuance of common stock upon vesting of restricted stock units, net of taxes withheld, shares Issuance Of Common Stock Upon Vesting Of Restricted Stock Units Net Of Taxes Withheld Shares Issuance of common stock upon vesting of restricted stock units,net of taxes withheld, shares. Exercised Issuance of common stock upon exercise of stock options, shares Stock Issued During Period Shares Stock Options Exercised Issuance of common stock upon exercise of stock options Stock Issued During Period Value Stock Options Exercised Beginning balance, shares Ending balance, shares Shares Outstanding Statement [Line Items] Statement [Line Items] Accumulated Deficit Retained Earnings [Member] Accumulated Other Comprehensive Income (Loss) Accumulated Other Comprehensive Income [Member] Additional Paid-In Capital Additional Paid In Capital [Member] Common Stock Common Stock [Member] Equity Component Equity Component [Domain] Equity Components Statement Equity Components [Axis] Statement [Table] Statement [Table] Statement Of Stockholders Equity [Abstract] Issuance of common stock upon exercise of common stock warrant Issuance Of Common Stock Upon Exercise Of Common Stock Warrants Issuance of common stock upon exercise of common stock warrants. Issuance of common stock upon vesting of restricted stock units, net of taxes withheld Issuance Of Common Stock Upon Vesting Of Restricted Stock Units Net Of Taxes Withheld Issuance of common stock upon vesting of restricted stock units,net of taxes withheld. Comprehensive loss Comprehensive Income Net Of Tax Total other comprehensive income (loss) Other Comprehensive Income Loss Net Of Tax Portion Attributable To Parent Change in unrealized gains related to available-for-sale debt securities, net of tax Other Comprehensive Income Availableforsale Securities Adjustment Net Of Tax Portion Attributable To Parent Other comprehensive income (loss) Other Comprehensive Income Loss Net Of Tax Portion Attributable To Parent [Abstract] Weighted-average common shares outstanding used in computing net loss per common share, basic and diluted Weighted Average Number Of Share Outstanding Basic And Diluted Net loss per common share, basic and diluted Earnings Per Share Basic And Diluted Net loss Net loss Net Income Loss Other income (expense), net Other Nonoperating Income Expense Interest expense Interest Expense Interest income Investment Income Interest Loss from operations Operating Income Loss Total operating expenses Operating Expenses General and administrative General And Administrative Expense Research and development Research And Development Expense Operating expenses Operating Expenses [Abstract] Income Statement [Abstract] Common stock, shares outstanding Common Stock Shares Outstanding Common stock, shares issued Common Stock Shares Issued Common stock, shares authorized Common Stock Shares Authorized Common stock, par value Common Stock Par Or Stated Value Per Share Preferred Stock, shares outstanding Preferred Stock Shares Outstanding Preferred Stock, shares issued Preferred Stock Shares Issued Preferred stock, shares authorized Preferred Stock Shares Authorized Preferred stock, par value Preferred Stock Par Or Stated Value Per Share Total liabilities and stockholders’ equity Liabilities And Stockholders Equity Total stockholders’ equity Beginning Balance Ending Balance Stockholders Equity Accumulated deficit Retained Earnings Accumulated Deficit Accumulated other comprehensive income Accumulated Other Comprehensive Income Loss Net Of Tax Additional paid-in capital Additional Paid In Capital Common Stock Common Stock Value Preferred Stock Value Stockholders’ equity: Stockholders Equity [Abstract] Commitments and contingencies (Note 6) Commitments And Contingencies Total liabilities Liabilities Local Phone Number Local Phone Number City Area Code City Area Code Entity Address, Postal Zip Code Entity Address Postal Zip Code Entity Address, State or Province Entity Address State Or Province Entity Address, City or Town Entity Address City Or Town Entity Address, Address Line One Entity Address Address Line1 Entity Tax Identification Number Entity Tax Identification Number Entity File Number Entity File Number Entity Common Stock, Shares Outstanding Entity Common Stock Shares Outstanding Entity Emerging Growth Company Entity Emerging Growth Company Entity Small Business Entity Small Business Entity Shell Company Entity Shell Company Entity Filer Category Entity Filer Category Current Fiscal Year End Date Current Fiscal Year End Date Revised estimated capital contribution Contractual Obligation Contractual Obligation, Total Annual suite fees payment Performance Based Restricted Stock Units [Member] Performance Based Restricted Stock Units [Member] Performance Based Restricted Stock Units Share-based Compensation Arrangement by Share-based Payment Award, Options, Vested, Number of Shares Stock options, vested Contractual obligation under funding agreement Share-based Compensation Arrangement by Share-based Payment Award, Number of Shares Authorized Issuance of common stock pursuant to employee stock purchase plans Marketable Securities Marketable Securities, Total Availability of Marketable Securities Other comprehensive income (loss) Subsequent Events Entity Interactive Data Current Entity Interactive Data Current