Commitments and Contingencies Disclosure [Abstract] Commitments and Contingencies Commitments and Contingencies Disclosure [Text Block] Statement of Stockholders' Equity [Abstract] Statement [Table] Statement [Table] Equity Components [Axis] Equity Components [Axis] Equity Component [Domain] Equity Component [Domain] Common Stock Common Stock [Member] Additional Paid-in Capital Additional Paid-in Capital [Member] Accumulated Other Comprehensive (Loss) Income AOCI Attributable to Parent [Member] Accumulated Deficit Retained Earnings [Member] Statement [Line Items] Statement [Line Items] Increase (Decrease) in Stockholders' Equity [Roll Forward] Increase (Decrease) in Stockholders' Equity [Roll Forward] Stockholders' Equity, Beginning Balance Stockholders' Equity Attributable to Parent Stockholders' Equity, Beginning Balance (in shares) Shares, Outstanding Shares issued under employee stock plans (in shares) Share-based Compensation Arrangement by Share-based Payment Award, Options, Exercises in Period Shares issued under employee stock plans Stock Issued During Period, Value, Stock Options Exercised Warrants exercised Stock Issued During Period, Value, Due To Warrants Exercised Stock Issued During Period, Value, Due To Warrants Exercised Warrants exercised (in shares) Stock Issued During Period, Shares, Due To Warrants Exercised Stock Issued During Period, Shares, Due To Warrants Exercised Stock-based compensation Adjustments to Additional Paid in Capital, Share-based Compensation, Stock Options, Requisite Service Period Recognition Comprehensive income, net Other Comprehensive Income (Loss), Net of Tax Net loss Net Income (Loss) Attributable to Parent Stockholders' Equity, Ending Balance Stockholders' Equity, Ending Balance (in shares) Schedule of Operating Leased Assets [Table] Schedule of Operating Leased Assets [Table] Lease Arrangement [Axis] Lease Arrangement [Axis] Lease Arrangement [Axis] Lease Arrangement [Domain] Lease Arrangement [Domain] [Domain] for Lease Arrangement [Axis] One office lease One Office Lease [Member] One Office Lease [Member] Operating Leased Assets [Line Items] Operating Leased Assets [Line Items] Non-cancellable office leases Lessee, Operating Lease, Number Lessee, Operating Lease, Number Operating lease, term of contract Lessee, Operating Lease, Term of Contract Number of one year renewal options Lessee, Operating Lease, One Year Renewal Options, Number Lessee, Operating Lease, One Year Renewal Options, Number Weighted-average discount rate Operating Lease, Weighted Average Discount Rate, Percent Statement of Financial Position [Abstract] Preferred stock, par value (in dollars per share) Preferred Stock, Par or Stated Value Per Share Preferred stock, shares authorized (in shares) Preferred Stock, Shares Authorized Preferred stock, shares issued (in shares) Preferred Stock, Shares Issued Preferred stock, shares outstanding (in shares) Preferred Stock, Shares Outstanding Common stock, par value (in dollars per share) Common Stock, Par or Stated Value Per Share Common stock, shares authorized (in shares) Common Stock, Shares Authorized Common stock, shares issued (in shares) Common Stock, Shares, Issued Common stock, shares outstanding (in shares) Common Stock, Shares, Outstanding Balance Sheet Related Disclosures [Abstract] Accrued compensation and related expenses Employee-related Liabilities, Current Accrued professional fees Accrued Professional Fees, Current Accrued research, development and manufacturing expenses Accrued Research And Contract Manufacturing Expenses, Current Accrued Research And Contract Manufacturing Expenses, Current Other Other Accrued Liabilities, Current Total accrued expenses Accrued Liabilities, Current Balance Sheet Accounts and Supplemental Disclosures Supplemental Balance Sheet Disclosures [Text Block] 2019 Operating Leases, Future Minimum Payments Due, Next Twelve Months 2020 Operating Leases, Future Minimum Payments, Due in Two Years 2021 Operating Leases, Future Minimum Payments, Due in Three Years 2022 Operating Leases, Future Minimum Payments, Due in Four Years 2023 Operating Leases, Future Minimum Payments, Due in Five Years Thereafter Operating Leases, Future Minimum Payments, Due Thereafter Total minimum payments required Operating Leases, Future Minimum Payments Due Equity [Abstract] Schedule of Common Stock Reserved for Future Issuance Schedule Of Common Stock Reserved For Future Issuance [Table Text Block] Schedule Of Common Stock Reserved For Future Issuance [Table Text Block] Fair Value Disclosures [Abstract] Fair Value Measurements, Recurring and Nonrecurring [Table] Fair Value Measurements, Recurring and Nonrecurring [Table] Measurement Frequency [Axis] Measurement Frequency [Axis] Fair Value, Measurement Frequency [Domain] Fair Value, Measurement Frequency [Domain] Fair Value, Measurements, Recurring Fair Value, Measurements, Recurring [Member] Fair Value Hierarchy and NAV [Axis] Fair Value Hierarchy and NAV [Axis] Fair Value Hierarchy and NAV [Domain] Fair Value Hierarchy and NAV [Domain] Quoted Market Prices for Identical Assets (Level 1) Fair Value, Inputs, Level 1 [Member] Significant Other Observable Inputs (Level 2) Fair Value, Inputs, Level 2 [Member] Significant Unobservable Inputs (Level 3) Fair Value, Inputs, Level 3 [Member] Cash and Cash Equivalents [Axis] Cash and Cash Equivalents [Axis] Cash and Cash Equivalents [Domain] Cash and Cash Equivalents [Domain] Money market funds Money Market Funds [Member] Mutual funds Mutual Fund [Member] Financial Instrument [Axis] Financial Instrument [Axis] Financial Instruments [Domain] Financial Instruments [Domain] U.S. treasury securities US Treasury Securities [Member] Certificates of deposit Certificates of Deposit [Member] Agency securities US Government Agencies Debt Securities [Member] Commercial and corporate obligations Commercial And Corporate Obligations [Member] Commercial And Corporate Obligations [Member] 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] Investments at fair value Cash And Cash Equivalents And Restricted Cash, Fair Value Disclosure Cash And Cash Equivalents And Restricted Cash, Fair Value Disclosure Available-for-sale securities, debt securities Debt Securities, Available-for-sale ASSETS Assets [Abstract] Current assets: Assets, Current [Abstract] Cash and cash equivalents Cash and Cash Equivalents, at Carrying Value Australian tax incentive receivable Research And Development Tax Incentive Credit Receivable, Current Research And Development Tax Incentive Credit Receivable, Current Short-term investments Debt Securities, Available-for-sale, Current Prepaid expenses and other current assets Prepaid Expense and Other Assets, Current Total current assets Assets, Current Property and equipment, net Property, Plant and Equipment, Net Long-term investments Debt Securities, Available-for-sale, Noncurrent Other long-term assets Other Assets, Noncurrent Restricted cash Restricted Cash and Cash Equivalents, Noncurrent Total assets Assets LIABILITIES AND STOCKHOLDERS’ EQUITY Liabilities and Equity [Abstract] Current liabilities: Liabilities, Current [Abstract] Accounts payable Accounts Payable, Current Accrued expenses Notes payable, current portion Notes Payable, Current Other current liabilities Other Liabilities, Current Total current liabilities Liabilities, Current Other long-term liabilities Other Liabilities, Noncurrent Stockholders’ equity: Stockholders' Equity Attributable to Parent [Abstract] Preferred stock, $0.001 par value, 10,000 shares authorized and no shares, issued or outstanding at March 31, 2019 and December 31, 2018, respectively Preferred Stock, Value, Issued Common stock, $0.001 par value, 500,000 shares authorized, 27,006 shares and 26,922 shares issued and outstanding at March 31, 2019 and December 31, 2018, respectively Common Stock, Value, Issued Additional paid in capital Additional Paid in Capital Accumulated other comprehensive income (loss) Accumulated Other Comprehensive Income (Loss), Net of Tax Accumulated deficit Retained Earnings (Accumulated Deficit) Total stockholders’ equity Total liabilities and stockholders’ equity Liabilities and Equity Document and Entity Information [Abstract] Document and Entity Information [Abstract] Entity Registrant Name Entity Registrant Name Entity Central Index Key Entity Central Index Key Current Fiscal Year End Date Current Fiscal Year End Date Entity Filer Category Entity Filer Category Document Type Document Type Document Period End Date Document Period End Date Document Fiscal Year Focus Document Fiscal Year Focus Document Fiscal Period Focus Document Fiscal Period Focus Amendment Flag Amendment Flag Entity Common Stock, Shares Outstanding Entity Common Stock, Shares Outstanding Entity Emerging Growth Company Entity Emerging Growth Company Entity Small Business Entity Small Business Revenue Recognition [Abstract] Schedule of Collaborative Arrangements and Non-collaborative Arrangement Transactions Schedule of Collaborative Arrangements and Non-collaborative Arrangement Transactions [Table Text Block] Operating ROU assets, Other long-term assets Operating Lease, Right-of-Use Asset Operating lease liabilities, Other current liabilities Operating Lease, Liability, Current Operating lease liabilities, Other long-term liabilities Operating Lease, Liability, Noncurrent Classification on the Balance Sheet Assets And Liabilities, Lessee [Table Text Block] Assets And Liabilities, Lessee [Table Text Block] Costs Included in Cash Flow Statement Lease, Cost [Table Text Block] Schedule of Future Minimum Annual Obligations Lessee, Operating Lease, Liability, Maturity [Table Text Block] Schedule of Future Minimum Annual Obligations Under Previous Lease Accounting Standard Schedule of Future Minimum Rental Payments for Operating Leases [Table Text Block] Debt Disclosure [Abstract] Schedule of Long-term Debt Instruments [Table] Schedule of Long-term Debt Instruments [Table] Long-term Debt, Type [Axis] Long-term Debt, Type [Axis] Long-term Debt, Type [Domain] Long-term Debt, Type [Domain] Notes Payable to Banks Notes Payable to Banks [Member] Debt Instrument [Axis] Debt Instrument [Axis] Debt Instrument, Name [Domain] Debt Instrument, Name [Domain] Loan and Security Agreement (LSA) Loan And Security Agreement [Member] Loan And Security Agreement [Member] Term Loans Term Loans [Member] Term Loans [Member] Term A Loans Term A Loans [Member] Term A Loans [Member] Term B and Term C Loans Term B Loans And Term C Loans [Member] Term B Loans And Term C Loans [Member] Variable Rate [Axis] Variable Rate [Axis] Variable Rate [Domain] Variable Rate [Domain] 3-Month LIBOR interest rate London Interbank Offered Rate (LIBOR) [Member] Debt Instrument [Line Items] Debt Instrument [Line Items] Debt instrument, maximum borrowing capacity Debt Instrument, Maximum Borrowing Capacity Debt Instrument, Maximum Borrowing Capacity Number of loan installments (in installments) Debt Instrument, Number Of Loan Installments Debt Instrument, Number Of Loan Installments Aggregate borrowing capacity Debt Instrument, Face Amount Aggregate draw on term loan Proceeds from Notes Payable Fixed interest rate (as a percent) Debt Instrument, Interest Rate, Stated Percentage Number of principal and interest payments (in payments) Debt Instrument, Periodic Payment, Number Of Principal And Interest Payments Debt Instrument, Periodic Payment, Number Of Principal And Interest Payments Basis spread on variable rate (as a percent) Debt Instrument, Basis Spread on Variable Rate Interest rate at period end (as a percent) Debt Instrument, Interest Rate At End Of Period Debt Instrument, Interest Rate At End Of Period Final payment fee Debt Instrument, Periodic Payment Terms, Balloon Payment to be Paid Notes payable Notes Payable Debt instrument discounts Debt Instrument, Unamortized Discount (Premium) and Debt Issuance Costs, Net Effective interest rate Debt Instrument, Interest Rate, Effective Percentage Long-term Debt, Fiscal Year Maturity [Abstract] Long-term Debt, Fiscal Year Maturity [Abstract] Debt maturities in remainder of year Long-term Debt, Maturities, Repayments of Principal, Remainder of Fiscal Year 2020 Long-term Debt, Maturities, Repayments of Principal in Year Two Income Statement [Abstract] Collaboration revenue Revenue from Contract with Customer, Including Assessed Tax Operating expenses: Operating Expenses [Abstract] Research and development Research and Development Expense General and administrative General and Administrative Expense Total operating expenses Operating Expenses Loss from operations Operating Income (Loss) Other income (expense), net: Nonoperating Income (Expense) [Abstract] Interest expense Interest Expense Interest income Interest Income (Expense), Nonoperating, Net Other income (expense), net Other Nonoperating Income (Expense) Total other income (expense), net Nonoperating Income (Expense) Loss before income taxes Income (Loss) from Continuing Operations before Equity Method Investments, Income Taxes, Noncontrolling Interest Provision for income taxes Income Tax Expense (Benefit) Net loss Unrealized income (loss) on available for sale securities, net of tax of $115 and $0, respectively Other Comprehensive Income (Loss), Securities, Available-for-Sale, Unrealized Holding Gain (Loss) Arising During Period, after Tax Comprehensive loss Comprehensive Income (Loss), Net of Tax, Attributable to Parent Net loss per common share: Earnings Per Share, Basic and Diluted [Abstract] Basic and diluted (in dollars per share) Earnings Per Share, Basic and Diluted Weighted-average number of shares outstanding: Earnings Per Share, Basic and Diluted, Other Disclosures [Abstract] Basic and diluted (in shares) Weighted Average Number of Shares Outstanding, Basic and Diluted Accounting Policies [Abstract] Schedule of Outstanding Potentially Dilutive Securities Excluded in the Calculation of Diluted Net Loss Per Share Schedule of Antidilutive Securities Excluded from Computation of Earnings Per Share [Table Text Block] Income Tax Disclosure [Abstract] Tax Credit Carryforward [Table] Tax Credit Carryforward [Table] Income Tax Authority, Name [Axis] Income Tax Authority, Name [Axis] Income Tax Authority, Name [Domain] Income Tax Authority, Name [Domain] Australian Taxation Office Australian Taxation Office [Member] Consolidated Entities [Axis] Consolidated Entities [Axis] Consolidated Entities [Domain] Consolidated Entities [Domain] Subsidiaries Subsidiaries [Member] Tax Credit Carryforward [Line Items] Tax Credit Carryforward [Line Items] Refundable tax incentive for qualified research and development activities (as a percent) Research And Development Tax Incentive Credit, Percentage Research And Development Tax Incentive Credit, Percentage Research and development Research And Development Tax Incentive Credit Research And Development Tax Incentive Credit Research and development tax incentive credit received during the period Research And Development Tax Incentive Credit Received During Period Research And Development Tax Incentive Credit Received During Period Basis of Presentation Basis of Accounting, Policy [Policy Text Block] Basis of Consolidation Consolidation, Policy [Policy Text Block] Use of Estimates Use of Estimates, Policy [Policy Text Block] Leases Lessee, Leases [Policy Text Block] Net Loss Per Common Share Earnings Per Share, Policy [Policy Text Block] Accounting Pronouncements Recently Adopted New Accounting Pronouncements, Policy [Policy Text Block] Fair Value Measurements and Available for Sale Investments Fair Value Disclosures [Text Block] Disclosure of Compensation Related Costs, Share-based Payments [Abstract] Shares Subject to Options Share-based Compensation Arrangement by Share-based Payment Award, Options, Outstanding [Roll Forward] Stock options outstanding, beginning balance (in shares) Share-based Compensation Arrangement by Share-based Payment Award, Options, Outstanding, Number Granted (in shares) Share-based Compensation Arrangement by Share-based Payment Award, Options, Grants in Period, Gross Exercises (in shares) Forfeitures and cancellations (in shares) Share-based Compensation Arrangement by Share-based Payment Award, Options, Forfeitures and Expirations in Period Stock options outstanding, ending balance (in shares) Stock options exercisable, ending balance (in shares) Share-based Compensation Arrangement by Share-based Payment Award, Options, Exercisable, Number Weighted-Average Exercise Price per Share Share-based Compensation Arrangement by Share-based Payment Award, Options, Outstanding, Weighted Average Exercise Price [Abstract] Stock options outstanding, beginning balance (in dollars per share) Share-based Compensation Arrangement by Share-based Payment Award, Options, Outstanding, Weighted Average Exercise Price Granted (in dollars per share) Share-based Compensation Arrangements by Share-based Payment Award, Options, Grants in Period, Weighted Average Exercise Price Exercises (in dollars per share) Share-based Compensation Arrangements by Share-based Payment Award, Options, Exercises in Period, Weighted Average Exercise Price Forfeitures and cancellations (in dollars per share) Share-based Compensation Arrangement by Share-based Payment Award, Options, Forfeitures and Expirations in Period, Weighted Average Exercise Price Stock options outstanding, ending balance (in dollars per share) Stock options exercisable, ending balance (in dollars per share) Share-based Compensation Arrangement by Share-based Payment Award, Options, Exercisable, Weighted Average Exercise Price Weighted-Average Remaining Contractual Term and Aggregate Intrinsic Value Share-based Compensation Arrangement by Share-based Payment Award, Options, Additional Disclosures [Abstract] Weighted average remaining contractual term, options outstanding (in years) Share-based Compensation Arrangement by Share-based Payment Award, Options, Outstanding, Weighted Average Remaining Contractual Term Weighted average remaining contractual term, options exercisable (in years) Share-based Compensation Arrangement by Share-based Payment Award, Options, Exercisable, Weighted Average Remaining Contractual Term Aggregate intrinsic value, options outstanding Share-based Compensation Arrangement by Share-based Payment Award, Options, Outstanding, Intrinsic Value Aggregate intrinsic value, options exercisable Share-based Compensation Arrangement by Share-based Payment Award, Options, Exercisable, Intrinsic Value Collaborative Research and Development Agreements Collaborative Arrangement Disclosure [Text Block] Equity Incentive Plans Disclosure of Compensation Related Costs, Share-based Payments [Text Block] Property, Plant and Equipment [Table] Property, Plant and Equipment [Table] Property, Plant and Equipment, Type [Axis] Property, Plant and Equipment, Type [Axis] Property, Plant and Equipment, Type [Domain] Property, Plant and Equipment, Type [Domain] Laboratory equipment Laboratory Equipment [Member] Laboratory Equipment [Member] Office furniture and equipment Office Equipment [Member] Leasehold improvements Leasehold Improvements [Member] Property, Plant and Equipment [Line Items] Property, Plant and Equipment [Line Items] Property and equipment, gross Property, Plant and Equipment, Gross Less: accumulated depreciation and amortization Accumulated Depreciation, Depletion and Amortization, Property, Plant, and Equipment Total property and equipment, net 2019 Lessee, Operating Lease, Liability, Payments, Remainder of Fiscal Year 2020 Lessee, Operating Lease, Liability, Payments, Due Year Two 2021 Lessee, Operating Lease, Liability, Payments, Due Year Three 2022 Lessee, Operating Lease, Liability, Payments, Due Year Four 2023 Lessee, Operating Lease, Liability, Payments, Due Year Five Thereafter Lessee, Operating Lease, Liability, Payments, Due after Year Five Total minimum payments required Lessee, Operating Lease, Liability, Payments, Due Less imputed interest Lessee, Operating Lease, Liability, Undiscounted Excess Amount Total Operating Lease, Liability Stockholders' Equity Stockholders' Equity Note Disclosure [Text Block] Property and Equipment Property, Plant and Equipment [Table Text Block] Schedule of Accrued Expenses Schedule of Accrued Liabilities [Table Text Block] Debt Securities, Available-for-sale [Table] Debt Securities, Available-for-sale [Table] Range [Axis] Range [Axis] Range [Domain] Range [Domain] Minimum Minimum [Member] Maximum Maximum [Member] Debt Securities, Available-for-sale [Line Items] Debt Securities, Available-for-sale [Line Items] Amortized Cost Debt Securities, Available-for-sale, Amortized Cost Gross Unrealized Gains Debt Securities, Available-for-sale, Accumulated Gross Unrealized Gain, before Tax Gross Unrealized Losses Debt Securities, Available-for-sale, Accumulated Gross Unrealized Loss, before Tax Total Fair Value Investments outstanding, maturity date range (in years) Available-for-sale Debt Securities, Remaining Maturity Available-for-sale Debt Securities, Remaining Maturity Deferred Revenue Arrangement, by Type [Table] Deferred Revenue Arrangement, by Type [Table] Counterparty Name [Axis] Counterparty Name [Axis] Counterparty Name [Domain] Counterparty Name [Domain] TESARO TESARO, Inc. And TESARO Development, Inc. [Member] TESARO, Inc. And TESARO Development, Inc. [Member] Celgene Corporation Celgene Corporation [Member] Celgene Corporation [Member] Type of Arrangement and Non-arrangement Transactions [Axis] Type of Arrangement and Non-arrangement Transactions [Axis] Arrangements and Non-arrangement Transactions [Domain] Arrangements and Non-arrangement Transactions [Domain] Collaborative Research And Development Agreement Collaborative Arrangement [Member] Initiated in vivo toxicology studies using good laboratory practices (GLPs) In Vivo Toxicology Studies [Member] In Vivo Toxicology Studies [Member] IND clearance from the FDA Clearance Of Investigational New Drug From FDA [Member] Clearance Of Investigational New Drug From FDA [Member] Phase 2 clinical trial initiation Phase 2 Clinical Trial Initiation [Member] Phase 2 Clinical Trial Initiation [Member] Phase 3 clinical trial initiation Phase 3 Clinical Trial Initiation [Member] Phase 3 Clinical Trial Initiation [Member] Phase 1 clinical trial initiation Phase 1 Clinical Trial Initiation [Member] Phase 1 Clinical Trial Initiation [Member] Product and Service [Axis] Product and Service [Axis] Product and Service [Domain] Product and Service [Domain] AnaptysBio-generated Anti-PD-1 Antagonist Antibody (TSR-042) AnaptysBio-generated Anti-PD-1 Antagonist Antibody (TSR-042) [Member] AnaptysBio-generated Anti-PD-1 Antagonist Antibody (TSR-042) [Member] AnaptysBio Generated Anti-TIM3 Antagonist Antibody (TSR-022) AnaptysBio Generated Anti-TIM3 Antagonist Antibody (TSR-022) [Member] AnaptysBio Generated Anti-TIM3 Antagonist Antibody (TSR-022) [Member] AnaptysBio Generated Anti-LAG3 Antagonist Antibody (TSR-033) AnaptysBio Generated Anti-LAG3 Antagonist Antibody (TSR-033) [Member] AnaptysBio Generated Anti-LAG3 Antagonist Antibody (TSR-033) [Member] AnaptysBio-Generated Anti-PD-1 Antagonist Antibody (CC-90006) AnaptysBio-Generated Anti-PD-1 Antagonist Antibody (CC-90006) [Member] AnaptysBio-Generated Anti-PD-1 Antagonist Antibody (CC-90006) [Member] Deferred Revenue Arrangement [Line Items] Deferred Revenue Arrangement [Line Items] Upfront license fee received Revenue Recognition, Multiple-deliverable Arrangements, Upfront Fee Received Revenue Recognition, Multiple-deliverable Arrangements, Upfront Fee Received Number of outstanding research and development targets Revenue Recognition, Milestone Method, Number Of Outstanding Research And Development Targets Revenue Recognition, Milestone Method, Number Of Outstanding Research And Development Targets Milestone payments, contingent upon preclinical and clinical trial events (up to) Revenue Recognition, Milestone Method, Contingent Upon Preclinical And Clinical Trial Events Revenue Recognition, Milestone Method, Contingent Upon Preclinical And Clinical Trial Events Milestone payments, contingent upon certain U.S. and European regulatory submissions and approvals (up to) Revenue Recognition, Milestone Method, Contingent Upon Certain United States And European Regulatory Submissions And Approvals Revenue Recognition, Milestone Method, Contingent Upon Certain United States And European Regulatory Submissions And Approvals Milestone payments, contingent upon achievement of specified levels of worldwide sales (up to) Revenue Recognition, Milestone Method, Contingent Upon Achievement Of Specified Levels Of Worldwide Sales Revenue Recognition, Milestone Method, Contingent Upon Achievement Of Specified Levels Of Worldwide Sales Agreement term following first commercial sale or expiration of the last to expire patent (in years) Revenue Recognition, Milestone Method, Agreement Term Following First Commercial Sale Or Expiration Of The Last To Expire Patent Revenue Recognition, Milestone Method, Agreement Term Following First Commercial Sale Or Expiration Of The Last To Expire Patent Milestones achieved, amount Revenue Recognition, Milestone Method, Milestones Achieved During The Period, Amount Revenue Recognition, Milestone Method, Milestones Achieved During The Period, Amount Maximum milestone payments per target Revenue Recognition, Milestone Method, Maximum Revenue Per Milestone Revenue Recognition, Milestone Method, Maximum Revenue Per Milestone Milestone payment earned Revenue Recognized, Milestone Method, Milestone Payment Earned Revenue Recognized, Milestone Method, Milestone Payment Earned Fair Value, by Balance Sheet Grouping [Table] Fair Value, by Balance Sheet Grouping [Table] Measurement Basis [Axis] Measurement Basis [Axis] Fair Value Measurement [Domain] Fair Value Measurement [Domain] Portion at Fair Value Measurement Portion at Fair Value Measurement [Member] Carrying Amount Reported Value Measurement [Member] Fair Value Estimate of Fair Value Measurement [Member] Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items] Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items] Notes payable Notes Payable, Fair Value Disclosure Unrealized income (loss) on available for sale securities, tax Other Comprehensive Income (Loss), Securities, Available-for-Sale, Unrealized Holding Gain (Loss) Arising During Period, Tax Schedule of Antidilutive Securities Excluded from Computation of Earnings Per Share [Table] Schedule of Antidilutive Securities Excluded from Computation of Earnings Per Share [Table] Antidilutive Securities [Axis] Antidilutive Securities [Axis] Antidilutive Securities, Name [Domain] Antidilutive Securities, Name [Domain] Options to purchase common stock Employee Stock Option [Member] Warrants to purchase common stock Warrant [Member] Class of Stock [Axis] Class of Stock [Axis] Class of Stock [Domain] Class of Stock [Domain] Antidilutive Securities Excluded from Computation of Earnings Per Share [Line Items] Antidilutive Securities Excluded from Computation of Earnings Per Share [Line Items] Dilutive securities excluded from computation of net loss per share (in shares) Antidilutive Securities Excluded from Computation of Earnings Per Share, Amount Australia Research and Development Tax Incentive Income Tax Disclosure [Text Block] Schedule of Share-based Compensation Arrangements by Share-based Payment Award [Table] Schedule of Share-based Compensation Arrangements by Share-based Payment Award [Table] Income Statement Location [Axis] Income Statement Location [Axis] Income Statement Location [Domain] Income Statement Location [Domain] Research and development Research and Development Expense [Member] General and administrative General and Administrative Expense [Member] Share-based Compensation Arrangement by Share-based Payment Award [Line Items] Share-based Compensation Arrangement by Share-based Payment Award [Line Items] Stock-based compensation Share-based Compensation And Issuance Of Stock And Warrants For Services Or Claims Share-based Compensation And Issuance Of Stock And Warrants For Services Or Claims Award Type [Axis] Award Type [Axis] Equity Award [Domain] Equity Award [Domain] Risk-free interest rate Share-based Compensation Arrangement by Share-based Payment Award, Fair Value Assumptions, Risk Free Interest Rate Expected volatility Share-based Compensation Arrangement by Share-based Payment Award, Fair Value Assumptions, Expected Volatility Rate Expected dividend yield Share-based Compensation Arrangement by Share-based Payment Award, Fair Value Assumptions, Expected Dividend Rate Expected term (in years) Share-based Compensation Arrangement by Share-based Payment Award, Fair Value Assumptions, Expected Term Weighted average grant date fair value per share (in dollars per share) Share-based Compensation Arrangement by Share-based Payment Award, Options, Grants in Period, Weighted Average Grant Date Fair Value Notes Payable Debt Disclosure [Text Block] Schedule of Stock by Class [Table] Schedule of Stock by Class [Table] Plan Name [Axis] Plan Name [Axis] Plan Name [Domain] Plan Name [Domain] 2017 Equity Incentive Plan Equity Incentive Plan, 2017 [Member] Equity Incentive Plan, 2017 [Member] 2017 Employee Stock Purchase Plan Employee Stock Purchase Plan, 2017 [Member] Employee Stock Purchase Plan, 2017 [Member] Class of Stock [Line Items] Class of Stock [Line Items] Issued and Outstanding: Common Stock, Number of Shares, Par Value and Other Disclosures [Abstract] Stock options issued and outstanding (in shares) Shares reserved for future award grants (in shares) Share-based Compensation Arrangement by Share-based Payment Award, Number of Shares Available for Grant Common stock, shares reserved for issuance (in shares) Common Stock, Capital Shares Reserved for Future Issuance Employee Stock Employee Stock [Member] Employee and Nonemployee Stock Options vesting period (in years) Employee And Nonemployee Stock Options [Member] Employee And Nonemployee Stock Options [Member] Title of Individual [Axis] Title of Individual [Axis] Relationship to Entity [Domain] Relationship to Entity [Domain] Director Stock options vesting period Director [Member] Annual increase in number of shares available for issuance Common Stock, Capital Shares Reserved For Future Issuance, Annual Increase, Percent Of Aggregate Shares Outstanding Common Stock, Capital Shares Reserved For Future Issuance, Annual Increase, Percent Of Aggregate Shares Outstanding Capital shares reserved for future issuance, increase (in shares) Common Stock, Capital Shares Reserved For Future Issuance, Increase Common Stock, Capital Shares Reserved For Future Issuance, Increase Award vesting period (in years) Share-based Compensation Arrangement by Share-based Payment Award, Award Vesting Period Award expiration period (in years) Share-based Compensation Arrangement by Share-based Payment Award, Expiration Period Unrecognized compensation cost Employee And Nonemployee Service Share-based Compensation, Nonvested Awards, Compensation Not Yet Recognized, Stock Options Employee And Nonemployee Service Share-based Compensation, Nonvested Awards, Compensation Not Yet Recognized, Stock Options Weighted average period remaining for amortization of unrecognized compensation cost (in years) Employee And Nonemployee Service Share-based Compensation, Nonvested Awards, Compensation Cost Not Yet Recognized, Period For Recognition Employee And Nonemployee Service Share-based Compensation, Nonvested Awards, Compensation Cost Not Yet Recognized, Period For Recognition Statement of Cash Flows [Abstract] CASH FLOWS FROM OPERATING ACTIVITIES: Net Cash Provided by (Used in) Operating Activities [Abstract] 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] Depreciation and amortization Depreciation, Depletion and Amortization Accretion of discount on investments Unrealized Gain (Loss) on Investments Non-cash interest expense Other Noncash Income (Expense) Changes in operating assets and liabilities: Increase (Decrease) in Operating Capital [Abstract] Australian tax incentive receivable Increase (Decrease) in Income Taxes Receivable Prepaid expenses and other assets Increase (Decrease) in Prepaid Expense and Other Assets Accounts payable and other liabilities Increase (Decrease) in Accounts Payable and Accrued Liabilities Net cash used in operating activities Net Cash Provided by (Used in) Operating Activities CASH FLOWS FROM INVESTING ACTIVITIES: Net Cash Provided by (Used in) Investing Activities [Abstract] Acquisition of investments Payments to Acquire Debt Securities, Available-for-sale Sales and maturities of investments Proceeds from Sale and Maturity of Debt Securities, Available-for-sale Purchases of property and equipment Payments to Acquire Property, Plant, and Equipment Net provided by investing activities Net Cash Provided by (Used in) Investing Activities CASH FLOWS FROM FINANCING ACTIVITIES: Net Cash Provided by (Used in) Financing Activities [Abstract] Proceeds from issuance of common stock, upon the exercise of stock options Proceeds from Stock Options Exercised Proceeds from issuance of common stock, upon the exercise of warrants Proceeds from Warrant Exercises Payments on notes payable Repayments of Notes Payable Payments for offering costs, net Payments of Stock Issuance Costs Net cash used in financing activities Net Cash Provided by (Used in) Financing Activities Net decrease in cash, cash equivalents, and restricted cash Cash, Cash Equivalents, Restricted Cash and Restricted Cash Equivalents, Period Increase (Decrease), Excluding Exchange Rate Effect Cash, cash equivalents and restricted cash, beginning of period Cash, Cash Equivalents, Restricted Cash and Restricted Cash Equivalents Cash, cash equivalents and restricted cash, end of period SUPPLEMENTAL DISCLOSURE OF CASH FLOW INFORMATION Supplemental Cash Flow Information [Abstract] Interest paid Interest Paid, Excluding Capitalized Interest, Operating Activities Non-cash investing and financing activities: Cash Flow, Noncash Investing and Financing Activities Disclosure [Abstract] Amounts accrued for property and equipment Capital Expenditures Incurred but Not yet Paid Summary of Significant Accounting Policies Significant Accounting Policies [Text Block] Organization, Consolidation and Presentation of Financial Statements [Abstract] Description of the Business Nature of Operations [Text Block] Schedule of Assets and Liabilities that Require Fair Value Measurements on a Recurring Basis Schedule of Fair Value, Assets and Liabilities Measured on Recurring Basis [Table Text Block] Fair Value of Other Financial Instruments Fair Value, by Balance Sheet Grouping [Table Text Block] Available-for-sale Investments Schedule of Available-for-sale Securities Reconciliation [Table Text Block] Number of reportable segments Number of Reportable Segments New Accounting Pronouncements or Change in Accounting Principle [Table] New Accounting Pronouncements or Change in Accounting Principle [Table] Adjustments for New Accounting Pronouncements [Axis] Adjustments for New Accounting Pronouncements [Axis] Type of Adoption [Domain] Type of Adoption [Domain] ASU 2016-02 Accounting Standards Update 2016-02 [Member] New Accounting Pronouncements or Change in Accounting Principle [Line Items] New Accounting Pronouncements or Change in Accounting Principle [Line Items] ROU assets Lease liabilities Operating lease cost Operating Lease, Cost Cash paid for amounts included in the measurement of lease liabilities Operating Lease, Payments Summary of Activity Related to Stock Option Awards Share-based Compensation, Stock Options, Activity [Table Text Block] Summary of Weighted Average Assumptions in Stock Option Valuations Schedule of Share-based Payment Award, Stock Options, Valuation Assumptions [Table Text Block] Summary of Non-cash Stock-based Compensation Expense Schedule of Compensation Cost for Share-based Payment Arrangements, Allocation of Share-based Compensation Costs by Plan [Table Text Block]