Retirement Benefits [Abstract] Employee Benefit Plan Pension and Other Postretirement Benefits Disclosure [Text Block] Share-based Payment Arrangement [Abstract] Equity Incentive Plans Share-based Payment Arrangement [Text Block] Balance Sheet Related Disclosures [Abstract] Accrued compensation and related expenses Employee-related Liabilities, Current Accrued professional fees Accrued Professional Fees, Current Accrued research and development expenses Accrued Research And Development Expenses, Current Accrued Research And Development Expenses, Current Other Other Accrued Liabilities, Current Total accrued expenses Accrued Liabilities, Current Statement of Financial Position [Abstract] Preferred Stock, Par or Stated Value 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 Income Tax Disclosure [Abstract] Australia Research and Development Tax Incentive Income Tax Disclosure [Text Block] Revenue Recognition [Abstract] Collaborative Arrangement and Arrangement Other than Collaborative [Table] Collaborative Arrangement and Arrangement Other than Collaborative [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] Collaborative Arrangement and Arrangement Other than Collaborative [Axis] Collaborative Arrangement and Arrangement Other than Collaborative [Axis] Collaborative Arrangement and Arrangement Other than Collaborative [Domain] Collaborative Arrangement and Arrangement Other than Collaborative [Domain] Collaborative Research and Development Agreement Collaborative Arrangement [Member] In Vivo Toxicology Studies Using 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 - first indication Phase 3 Clinical Trial Initiation [Member] Phase 3 Clinical Trial Initiation [Member] Phase 3 clinical 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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 Number of milestones achieved during period Revenue 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[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] Award Type [Axis] Award Type [Axis] Award Type [Domain] Award Type [Domain] Employee Stock Employee Stock [Member] Employee and Nonemployee Stock Options Employee And Nonemployee Stock Options [Member] Employee And Nonemployee Stock Options [Member] Options Share-based Payment Arrangement, Option [Member] Title of Individual [Axis] Title of Individual [Axis] Title of Individual [Domain] Title of Individual [Domain] Director Director [Member] Share-based Compensation Arrangement by Share-based Payment Award [Line Items] Share-based Compensation Arrangement by Share-based Payment Award [Line Items] 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 Proceeds from issuance of common stock, upon the exercise of stock options Proceeds from Stock Options Exercised 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 Commitments and Contingencies Disclosure [Abstract] Lessee, Operating Lease, Liability, Payment, Due [Abstract] Lessee, Operating Lease, Liability, Payment, Due [Abstract] 2020 Lessee, Operating Lease, Liability, Payments, Due Next Twelve Months 2021 Lessee, Operating Lease, Liability, Payments, Due Year Two 2022 Lessee, Operating Lease, Liability, Payments, Due Year Three 2023 Lessee, Operating Lease, Liability, Payments, Due Year Four 2024 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 Present value of lease liabilities Operating Lease, Liability Operating Leases, Future Minimum Payments Due, Fiscal Year Maturity [Abstract] Operating Leases, Future Minimum Payments Due, Fiscal Year Maturity [Abstract] 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 Components of Income/(Loss) before Income Tax Provision (Benefit) Schedule of Income before Income Tax, Domestic and Foreign [Table Text Block] Schedule of Components of Deferred Tax Assets and Liabilities Schedule of Deferred Tax Assets and Liabilities [Table Text Block] Reconciliation of Expected Statutory Federal Income Tax Provision and Actual Income Tax Provision Schedule of Components of Income Tax Expense (Benefit) [Table Text Block] Schedule of Activity Related to Unrecognized Tax Benefits Schedule of Unrecognized Tax Benefits Roll Forward [Table Text Block] Accounting Policies [Abstract] 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] Warrants Warrant [Member] Class of Stock [Axis] Class of Stock [Axis] Class of Stock [Domain] Class of Stock [Domain] Common Stock Common Stock [Member] 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 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 December 31, 2019 and December 31, 2018, respectively Preferred Stock, Value, Issued Common stock, $0.001 par value, 500,000 shares authorized, 27,255 shares and 26,922 shares issued and outstanding at December 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 Stockholders' Equity Attributable to Parent Total liabilities, preferred stock and stockholders’ equity Liabilities and Equity Quarterly Financial Information Disclosure [Abstract] Selected Quarterly Financial Data (Unaudited) Quarterly Financial Information [Text Block] Operating lease cost Operating Lease, Cost Cash paid for amounts included in the measurement of lease liabilities Operating Lease, Payments Schedule of Milestones Achieved Collaborative Arrangement and Arrangement Other than Collaborative [Table Text Block] Summary of Activity Related to Stock Option Awards Share-based Payment Arrangement, Option, 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 Share-based Payment Arrangement, Cost by Plan [Table Text Block] 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 Debt Disclosure [Abstract] Notes Payable Debt Disclosure [Text Block] Subsequent Events [Abstract] Subsequent Events Subsequent Events [Text Block] Operating income (loss) Operating Income (Loss) Net income (loss) Net Income (Loss) Available to Common Stockholders, Basic Per common share: Earnings Per Share, Basic and Diluted [Abstract] Loss per share, basic (in dollars per share) Earnings Per Share, Basic Loss per share, diluted (in dollars per share) Earnings Per Share, Diluted Balance Sheet Accounts and Supplemental Disclosures Supplemental Balance Sheet Disclosures [Text Block] Schedule of ROU Assets and Lease Liabilities Assets And Liabilities, Lessee [Table Text Block] Assets And Liabilities, Lessee [Table Text Block] Costs in Cash Flow Statement Lease, Cost [Table Text Block] Schedule of Future Minimum Annual Obligations under Operating Leases Lessee, Operating Lease, Liability, Maturity [Table Text Block] Schedule of Future Minimum Annual Obligations under Operating Leases Schedule of Future Minimum Rental Payments for Operating Leases [Table Text Block] Cover page. Document Type Document Type Document Annual Report Document Annual Report Document Period End Date Document Period End Date Document Transition Report Document Transition Report Entity File Number Entity File Number Entity Registrant Name Entity Registrant Name Entity Incorporation, State or Country Code Entity Incorporation, State or Country Code Entity Tax Identification Number Entity Tax Identification Number Entity Address, Address Line One Entity Address, Address Line One Entity Address, Address Line Two Entity Address, Address Line Two Entity Address, City or Town Entity Address, City or Town Entity Address, State or Province Entity Address, State or Province Entity Address, Postal Zip Code Entity Address, Postal Zip Code City Area Code City Area Code Local Phone Number Local Phone Number Title of 12(b) Security Title of 12(b) Security Trading Symbol Trading Symbol Security Exchange Name Security Exchange Name Entity Well-known Seasoned Issuer Entity Well-known Seasoned Issuer 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Consolidation Consolidation, Policy [Policy Text Block] Use of Estimates Use of Estimates, Policy [Policy Text Block] Cash and Cash Equivalents Cash and Cash Equivalents, Policy [Policy Text Block] Short Term and Long Term Investments Marketable Securities, Policy [Policy Text Block] Concentration of Credit Risk Concentration Risk, Credit Risk, Policy [Policy Text Block] Property and Equipment Property, Plant and Equipment, Policy [Policy Text Block] Long Lived Assets Property, Plant and Equipment, Impairment [Policy Text Block] Leases Lessee, Leases [Policy Text Block] Debt Issuance Costs Debt, Policy [Policy Text Block] Revenue Recognition Revenue from Contract with Customer [Policy Text Block] Research and Development Expenses Research and Development Expense, Policy [Policy Text Block] Share-Based Compensation Share-based Payment Arrangement [Policy Text Block] Warrants for Shares of Preferred Stock Derivatives, Policy [Policy Text Block] Income Taxes Income Tax, Policy [Policy 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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 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Upfront, Milestone And Royalty Expense Collaboration License Agreement, Upfront, Milestone And Royalty Expense Cash payments under licensing agreements Payments For Upfront, Milestone, And Royalty Payments Payments For Upfront, Milestone, And Royalty Payments Future minimum annual cash obligations, next 12 months Other Commitment, Due in Next Twelve Months Future minimum annual cash obligations, thereafter Other Commitments, Due After Year One Other Commitments, Due After Year One License agreement, obligation payable period Collaboration License Agreement, Obligation Payable Period Collaboration License Agreement, Obligation Payable Period Letters of credit outstanding Letters of Credit Outstanding, Amount 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] Fair Value, by Balance Sheet Grouping [Table] Fair Value, by 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Common Stock, Capital Shares Reserved for Future Issuance Commitments and Contingencies Commitments and Contingencies Disclosure [Text Block] Income Statement [Abstract] 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 Other income (expense), net: Nonoperating Income (Expense) [Abstract] Interest expense Interest Expense Change in fair value of liability for preferred stock warrants Fair Value Adjustment of Warrants Interest income Interest Income, Other Other (expense) income, net Other Nonoperating Income (Expense) Total other income (expense), net Nonoperating Income (Expense) Loss before income taxes Income (Loss) from Continuing Operations before Income Taxes, Noncontrolling Interest Provision for income taxes Income Tax Expense (Benefit) Net loss Other comprehensive income (loss): Comprehensive Income (Loss), Net of Tax, Attributable to Parent [Abstract] Unrealized income (loss) on available for sale securities, net of tax of $153, $55, and $0, respectively Other Comprehensive Income (Loss), Securities, Available-for-Sale, Unrealized Holding Gain (Loss) Arising During Period, before Tax Comprehensive loss Comprehensive Income (Loss), Net of Tax, Attributable to Parent Net loss per common share: 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 Operating lease liabilities Operating Lease, Liability, Current Operating lease liabilities Operating Lease, Liability, Noncurrent 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] Fair Value, Recurring and Nonrecurring [Table] Fair Value, Recurring and Nonrecurring [Table] Measurement Frequency [Axis] Measurement Frequency [Axis] Measurement Frequency [Domain] Measurement Frequency [Domain] Fair Value, Measurements, Recurring Fair Value, 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] 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 Property and Equipment Property, Plant and Equipment [Table Text Block] Schedule of Accrued Expenses Schedule of Accrued Liabilities [Table Text Block] 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] Expected income tax benefit at federal statutory tax rate Effective Income Tax Rate Reconciliation at Federal Statutory Income Tax Rate, Amount State income taxes, net of federal benefit Effective Income Tax Rate Reconciliation, State and Local Income Taxes, Amount Permanent items Effective Income Tax Rate Reconciliation, Tax Exempt Income, Amount Equity compensation Effective Income Tax Rate Reconciliation, Nondeductible Expense, Share-based Payment Arrangement, Amount Change in fair value of preferred stock warrant liabilities Effective Income Tax Rate Reconciliation, Change In Fair Value Of Preferred Stock Warrant Liabilities Effective Income Tax Rate Reconciliation, Change In Fair Value Of Preferred Stock Warrant Liabilities Research and development expenditure Effective Income Tax Rate Reconciliation, Nondeductible Expense, Research and Development, Amount Refundable AMT credit Effective Income Tax Rate Reconciliation, Alternative Minimum Tax Effective Income Tax Rate Reconciliation, Alternative Minimum Tax Return to provision adjustment Effective Income Tax Rate Reconciliation, Tax Settlement, Amount Rate differential Effective Income Tax Rate Reconciliation, Foreign Income Tax Rate Differential, Amount Federal rate adjustment - tax reform Effective Income Tax Rate Reconciliation, Change in Enacted Tax Rate, Amount Research credits Effective Income Tax Rate Reconciliation, Tax Credit, Research, Amount Change in the valuation allowance Effective Income Tax Rate Reconciliation, Change in Deferred Tax Assets Valuation Allowance, Amount Income tax benefit Excess tax benefits associated with the exercise of non-qualified stock options Effective Income Tax Rate Reconciliation, Tax Expense (Benefit), Share-based Payment Arrangement, Amount Disqualifying dispositions of incentive stock options Effective Income Tax Rate Reconciliation, Nondeductible Expense, Share-based Compensation Cost, Disqualifying Dispositions Of Incentive Stock Options Effective Income Tax Rate Reconciliation, Nondeductible Expense, Share-based Compensation Cost, Disqualifying Dispositions Of Incentive Stock Options Summary of quarterly results Quarterly Financial Information [Table Text Block] Income Taxes Reconciliation of Unrecognized Tax Benefits, Excluding Amounts Pertaining to Examined Tax Returns [Roll Forward] Reconciliation of Unrecognized Tax Benefits, Excluding Amounts Pertaining to Examined Tax Returns [Roll Forward] Balance at the beginning of the year Unrecognized Tax Benefits Increase related to prior year tax positions Unrecognized Tax Benefits, Increase Resulting from Prior Period Tax Positions Increase related to current year tax positions Unrecognized Tax Benefits, Increase Resulting from Current Period Tax Positions Balance at the end of the year 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 Change in fair value of liability for preferred stock warrants Accretion/amortization of investments, net Accretion (Amortization) of Discounts and Premiums, Investments Non-cash interest expense Other Noncash Income (Expense) Income taxes Increase (Decrease) in Income Taxes Payable Changes in operating assets and liabilities: Increase (Decrease) in Operating Capital [Abstract] Receivable from collaborative partners Increase (Decrease) in Contract with Customer, Asset 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 cash provided by (used in) 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 public offerings, net of underwriters' fees 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) provided by financing activities Net Cash Provided by (Used in) Financing Activities Net increase 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 Amounts accrued for offering costs Stock Issuance Costs Incurred During Noncash Transaction Stock Issuance Costs Incurred During Noncash Transaction Reclassification of warrants to equity Transfer Of Warrants To Equity Transfer Of Warrants To Equity Operating Loss Carryforwards [Table] Operating Loss Carryforwards [Table] Income Tax Authority [Axis] Income Tax Authority [Axis] Income Tax Authority [Domain] Income Tax Authority [Domain] Federal tax authority Domestic Tax Authority [Member] State tax authority State and Local Jurisdiction [Member] Foreign tax authority Foreign Tax Authority [Member] Tax Period [Axis] Tax Period [Axis] Tax Period [Domain] Tax Period [Domain] 2018 Tax Year 2018 [Member] Tax Credit Carryforward [Axis] Tax Credit Carryforward [Axis] Tax Credit Carryforward, Name [Domain] Tax Credit Carryforward, Name [Domain] Research Tax Credit Carryforward Research Tax Credit Carryforward [Member] Operating Loss Carryforwards [Line Items] Operating Loss Carryforwards [Line Items] Net operating loss carryforwards Operating Loss Carryforwards Research tax credit carryforwards Tax Credit Carryforward, Amount Net operating loss carryforward, utilization limitation Operating Loss Carryforwards, Limitations On Use, Amount Operating Loss Carryforwards, Limitations On Use, Amount Tax credit carryforward, utilization limitation Tax Credit Carryforward, Limitations On Use, Amount Tax Credit Carryforward, Limitations On Use, Amount Tax act, change in tax rate, decrease in deferred tax asset Tax Cuts and Jobs Act, Change in Tax Rate, Deferred Tax Asset, Income Tax Expense Unrecognized tax benefits that if recognized and realized would affect the effective tax rate Unrecognized Tax Benefits that Would Impact Effective Tax Rate Interest or penalties on uncertain tax benefits Unrecognized Tax Benefits, Income Tax Penalties and Interest Expense Description of the Business Nature of Operations [Text Block] Summary of Significant Accounting Policies Significant Accounting Policies [Text Block] Fair Value Measurements and Available for Sale Investments Fair Value Disclosures [Text Block] 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] Class of Warrant or Right [Axis] Class of Warrant or Right [Axis] Class of Warrant or Right [Domain] Class of Warrant or Right [Domain] Term A Loan Warrants Term A Loan Warrants [Member] Term A Loan Warrants [Member] Term B and C Loans Warrants Term B And C Loans Warrants [Member] Term B And C Loans Warrants [Member] Series C Preferred Stock Derivative Instrument [Axis] Derivative Instrument [Axis] Derivative Contract [Domain] Derivative Contract [Domain] Measurement Input Type [Axis] Measurement Input Type [Axis] Measurement Input Type [Domain] Measurement Input Type [Domain] Price volatility percent Measurement Input, Price Volatility [Member] Contractual term Measurement Input, Expected Term [Member] Risk-free interest rate Measurement Input, Risk Free Interest Rate [Member] Variable Rate [Axis] Variable Rate [Axis] Variable Rate [Domain] Variable Rate [Domain] 3-Month LIBOR 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 Debt Instrument, Interest Rate, Stated Percentage Warrant exercise price (in dollars per share) Class of Warrant or Right, Exercise Price of Warrants or Rights U.S. treasury securities Derivative Liability Measurement Input (as a percent) Debt Instrument, Measurement Input Contractual term (in years) Warrants and Rights Outstanding, Term 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 Debt Instrument, Basis Spread on Variable Rate Interest rate at period end 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 Debt instrument discounts Debt Instrument, Unamortized Discount (Premium) and Debt Issuance Costs, Net Remaining principal payments Long-term Debt, Maturities, Repayments of Principal in Next Twelve Months Effective interest rate Debt Instrument, Interest Rate, Effective Percentage U.S. Income (Loss) from Continuing Operations before Income Taxes, Domestic Foreign Income (Loss) from Continuing Operations before Income Taxes, Foreign Employer match, percent of contributions Defined Contribution Plan, Employer Matching Contribution, Percent of Match Employer match, percent of employees' gross pay Defined Contribution Plan, Employer Matching Contribution, Percent of Employees' Gross Pay Employer match, maximum contributions Defined Contribution Plan, Maximum Annual Contributions Per Employee, Amount Employer contributions to the plan Defined Contribution Plan, Employer Discretionary Contribution Amount Income tax expense related to other comprehensive income Other Comprehensive Income (Loss), Securities, Available-for-Sale, Unrealized Holding Gain (Loss) Arising During Period, Tax