Document and Entity Information [Abstract] Document Information [Table] Document Information [Line Items] Document Type Document Period End Date Entity Registrant Name Entity Current Reporting Status Entity Filer Category Entity Interactive Data Current Entity Small Business Entity Emerging Growth Company Entity Ex Transition Period Entity Shell Company Entity Common Stock, Shares Outstanding Current Fiscal Year End Date Document Fiscal Year Focus Document Fiscal Period Focus Entity Central Index Key Amendment Flag Statement of Financial Position [Abstract] Statement [Table] Statement [Line Items] Assets [Abstract] Assets Assets, Current [Abstract] Current assets: Cash Cash at end of period Cash at beginning of period Prepaid Expense and Other Assets, Current Prepaid and other current assets Assets, Current Total current assets Property, Plant and Equipment, Net Equipment, net Other Assets, Noncurrent Other assets Assets Total assets Liabilities and Equity [Abstract] Liabilities and stockholders? equity Liabilities, Current [Abstract] Current liabilities: Accounts Payable, Current Accounts payable Accounts Payable and Other Accrued Liabilities, Current Accrued expenses and other current liabilities Total Long-term Debt, Current Maturities Loan payable, current portion Loan payable, current portion Liabilities, Current Total current liabilities Long-term Debt, Excluding Current Maturities Loan payable, long-term Loan payable, long-term Liabilities Total liabilities Stockholders' Equity Attributable to Parent [Abstract] Stockholders' equity: Preferred Stock, Value, Issued Preferred stock, $0.0001 par value per share (10,000,000 shares authorized, none issued and outstanding at March 31, 2020 and December 31, 2019, respectively) Common Stock, Value, Issued Common stock, $0.0001 par value per share (150,000,000 shares authorized, 37,075,422 and 36,933,217 shares issued and outstanding at March 31, 2020 and December 31, 2019, respectively) Value of common stock Additional Paid in Capital Additional paid-in capital Retained Earnings (Accumulated Deficit) Accumulated deficit Accumulated deficit Stockholders' Equity Attributable to Parent Ending balance Beginning balance Total stockholders' equity Liabilities and Equity Total liabilities and stockholders' equity Preferred Stock, Par or Stated Value Per Share Preferred stock, par value Preferred Stock, Shares Authorized Preferred stock, shares authorized Preferred Stock, Shares Issued Preferred stock, shares issued Preferred Stock, Shares Outstanding Preferred stock, shares outstanding Common Stock, Par or Stated Value Per Share Common stock, par value Common Stock, Shares Authorized Common stock, shares authorized Common Stock, Shares, Issued Balance (in shares) Balance (in shares) Common stock, shares issued Number of common shares Common Stock, Shares, Outstanding Common stock, shares outstanding Income Statement [Abstract] Operating Expenses [Abstract] Operating expenses: Research and Development Expense Research and development Research and development expense recognized General and Administrative Expense General and administrative Operating Expenses Total operating expenses Operating Income (Loss) Loss from operations Investment Income, Net Interest and amortization of debt discount (expense) Net Income (Loss) Attributable to Parent Net loss Net loss Earnings Per Share, Basic and Diluted Net loss per common share, basic and diluted Weighted Average Number of Shares Outstanding, Basic and Diluted Weighted average common shares outstanding, basic and diluted Statement of Stockholders' Equity [Abstract] Equity Components [Axis] Equity Component [Domain] Equity Component [Domain] Common Stock [Member] Common Stock Additional Paid In Capital [Member] Additional paid-in capital Retained Earnings [Member] Accumulated deficit Adjustments to Additional Paid in Capital, Share-based Compensation, Requisite Service Period Recognition Stock-based compensation Stock Issued During Period, Value, Stock Options Exercised Issuance of common stock upon exercise of options Share-based Compensation Arrangement by Share-based Payment Award, Options, Exercises in Period Exercised (in shares) Issuance of common stock upon exercise of options (in shares) Value of warrants issued during period with debt financing. Warrants Issued During Period, Debt Financing Issuance of warrants upon debt financing Value of stock issued pursuant to a financing arrangement during the period. Stock Issued During Period, Value, Financing Issuance of common stock upon financing Number of shares of stock issued during the period pursuant to a financing arrangement. Stock Issued During Period Shares Financing Issuance of common stock upon financing (in shares) Statement of Cash Flows [Abstract] Net Cash Provided by (Used in) Operating Activities [Abstract] Cash flows from operating activities Net Income (Loss), Including Portion Attributable to Noncontrolling Interest Net loss Adjustments, Noncash Items, to Reconcile Net Income (Loss) to Cash Provided by (Used in) Operating Activities [Abstract] Adjustments to reconcile net loss to net cash used in operating activities: Share-based Compensation Stock-based compensation expense The aggregate noncash costs incurred (1) in a planned search or critical investigation aimed at discovery of new knowledge with the hope that such knowledge will be useful in developing a new product or service, a new process or technique, or in bringing about a significant improvement to an existing product or process; or (2) to translate research findings or other knowledge into a plan or design for a new product or process or for a significant improvement to an existing product or process whether intended for sale or the entity's use, during the reporting period charged to research and development projects, including the costs of developing computer software up to the point in time of achieving technological feasibility, and costs allocated in accounting for a business combination to in-process projects deemed to have no alternative future use. Noncash Research and Development Expense Non-cash research and development license expense Amortization of Debt Discount (Premium) Amortization of debt discount Depreciation Increase (Decrease) in Operating Capital [Abstract] Changes in operating assets and liabilities: The increase (decrease) during the reporting period in the value of prepaid expenses and other current assets not separately disclosed in the statement of cash flows, for example, deferred expenses, intangible assets, or income taxes. Increase (Decrease) in Prepaid Expense and Other Assets, Current Prepaid expenses and other current assets Increase (Decrease) in Other Noncurrent Assets Other assets Increase (Decrease) in Accounts Payable Accounts payable Increase (Decrease) in Other Accounts Payable and Accrued Liabilities Accrued expenses and other current liabilities Net Cash Provided by (Used in) Operating Activities Net cash used in operating activities Net Cash Provided by (Used in) Investing Activities [Abstract] Cash flows from investing activities Payments to Acquire Property, Plant, and Equipment Purchases of equipment Net Cash Provided by (Used in) Investing Activities Net cash used in investing activities Net Cash Provided by (Used in) Financing Activities [Abstract] Cash flows from financing activities Proceeds from Issuance of Common Stock Procceds from issuance of common stock upon financing, net Proceeds from Stock Options Exercised Proceeds from issuance of common stock upon exercise of options Proceeds from Issuance of Long-term Debt Proceeds from issuance of term loan Proceeds from (Repayments of) Notes Payable Repayment of principal on term loan Repayment of principal on term loan Net Cash Provided by (Used in) Financing Activities Net cash (used in) provided by financing activities Cash and Cash Equivalents, Period Increase (Decrease) Net (decrease) increase in cash Supplemental Cash Flow Information [Abstract] Supplemental disclosures of cash flow information: Interest Paid, Excluding Capitalized Interest, Operating Activities Interest paid Cash Flow, Noncash Investing and Financing Activities Disclosure [Abstract] Supplemental disclosures of non-cash financing activity: Warrants issued with debt financing. Warrants Issued With Debt Financing Issuance of warrants in connection with debt financing Nature of Business and Basis of Presentation Organization, Consolidation and Presentation of Financial Statements Disclosure [Text Block] Nature of Business and Basis of Presentation Summary of Significant Accounting Policies Significant Accounting Policies [Text Block] Summary of Significant Accounting Policies Accrued Expenses and Other Current Liabilities Accounts Payable and Accrued Liabilities Disclosure [Text Block] Accrued Expenses and Other Current Liabilities Debt Disclosure [Abstract] Long-term Debt [Text Block] Loan and Security Agreement Net Loss per Common Share Earnings Per Share [Text Block] Net Loss per Common Share Stockholders' Equity Stockholders' Equity Note Disclosure [Text Block] Stockholders' Equity License Agreements. The entire disclosure for license agreements. License Agreements Disclosure [Text Block] License Agreements Disclosure of accounting policy for significant risks and uncertainties. Significant Risks and Uncertainties, Policy, [Policy Text Block] Significant Risks and Uncertainties Use of Estimates, Policy [Policy Text Block] Use of Estimates Foreign Currency Transactions and Translations Policy [Policy Text Block] Foreign Currency Translation Segment Reporting, Policy [Policy Text Block] Segment and Geographic Information Cash and Cash Equivalents, Policy [Policy Text Block] Cash Equivalents Concentration Risk, Credit Risk, Policy [Policy Text Block] Concentration of Credit Risk Fair Value of Financial Instruments, Policy [Policy Text Block] Fair Value of Financial Instruments Debt, Policy [Policy Text Block] Debt Issuance Costs Property, Plant and Equipment, Policy [Policy Text Block] Equipment Research and Development Expense, Policy [Policy Text Block] Research and Development Costs Income Tax, Policy [Policy Text Block] Income Taxes Share-based Compensation, Option and Incentive Plans Policy [Policy Text Block] Stock Based Compensation Earnings Per Share, Policy [Policy Text Block] Basic and Diluted Net Loss per Common Share New Accounting Pronouncements, Policy [Policy Text Block] Recent Accounting Pronouncements Accrued Expenses Schedule of Accrued Liabilities [Table Text Block] Schedule of accrued expenses Schedule of Long-term Debt Instruments [Table Text Block] Schedule of outstanding debt and unamortized debt discount balances Schedule of Maturities of Long-term Debt [Table Text Block] Schedule of principal payments Schedule of Earnings Per Share, Basic and Diluted [Table Text Block] Computation of basic and diluted net loss per common share Schedule of Antidilutive Securities Excluded from Computation of Earnings Per Share [Table Text Block] Schedule of potentially dilutive securities Schedule of Share-based Compensation, Stock Options, Activity [Table Text Block] Schedule of stock option activity Share-based Payment Arrangement, Restricted Stock and Restricted Stock Unit, Activity [Table Text Block] Schedule of RSU activity Schedule of Employee Service Share-based Compensation, Allocation of Recognized Period Costs [Table Text Block] Schedule of stock-based compensation expense Schedule of Stockholders' Equity Note, Warrants or Rights [Table Text Block] Schedule of warrant activity Represents the number of late-stage candidates included in the Company's product candidate portfolio. Number of Late-stage Product Candidates Number of late-stage candidates in Company's product candidate portfolio Segment Reporting, Disclosure of Entity's Reportable Segments [Abstract] Segment and Geographic Information Number of Operating Segments Number of operating segments Cash Equivalents, at Carrying Value [Abstract] Cash Equivalents Cash Equivalents, at Carrying Value Cash Equivalents Risks and Uncertainties [Abstract] Concentration of Credit Risk Represents the number of financial institutions holding the Company's cash. Number of Financial Institutions Holding Deposits Number of financial institutions that hold the Company's cash Property, Plant and Equipment [Abstract] Equipment Property, Plant and Equipment, Useful Life Estimated useful life Effective Income Tax Rate Reconciliation, Percent [Abstract] Income Taxes Effective Income Tax Rate Reconciliation, Percent Effective tax rate Carrying value as of the balance sheet date of obligations incurred through that date and payable for research and development. Used to reflect the current portion of the liabilities (due within one year or within the normal operating cycle if longer). Accrued Research and Development, Current Research and development Employee-related Liabilities, Current Accrued compensation Other Accrued Liabilities, Current Other Range [Axis] Range [Member] Range [Domain] Minimum [Member] Minimum Maximum [Member] Maximum Debt Instrument [Axis] Debt Instrument Name [Domain] Debt Instrument, Name [Domain] Line Of Credit [Member] Term Loan Line of Credit Facility, Maximum Borrowing Capacity Maximum loan amount Represents the number of loan tranches pertaining to the debt instrument. Debt Instrument, Number of Loan Tranches Number of loan tranches Debt Instrument, Face Amount Loan amount Line of Credit Facility, Remaining Borrowing Capacity Remaining credit facility to be drawn Period of time during which interest-only payments are required for the debt instrument, in PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days. Debt Instrument, Interest Only Payments, Term Interest-only payment period The number of monthly installment to be paid Number Of Monthly Installments Number of monthly installments Debt Instrument, Interest Rate, Basis for Effective Rate Annual interest rate Debt Instrument, Basis Spread on Variable Rate Interest rate spread Interest rate basis The percent of principal due, as a final payment fee, at extinguishment of debt. Extinguishment of Debt, Fee, Percent of Principal Final payment fee, percent of principal The final payment fee at extinguishment of debt. Extinguishment Of Debt, Fee Amount Final payment fee Represents the prepayment premium due, as a percent of the outstanding principal, if prepayment occurs under condition one. Debt Instrument, Prepayment Premium, Percent of Outstanding Principal, Condition One Prepayment premium, percent of principal, if prepaid within two years Represents the prepayment premium due, as a percent of the outstanding principal, if prepayment occurs under condition one. Debt Instrument Prepayment Premium Percent Of Outstanding Principal Condition One Prepayment premium, percent of principal, if prepaid within one year The period of time during which prepayment premium condition one is in effect, in PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days. Debt Instrument, Prepayment Premium Condition One, Term Prepayment premium, condition one, term Represents the prepayment premium due, as a percent of the outstanding principal, if prepayment occurs under condition two. Debt Instrument, Prepayment Premium, Percent of Outstanding Principal, Condition Two Prepayment premium, percent of principal, if prepaid during the third year Represents the prepayment premium due, as a percent of the outstanding principal, if prepayment occurs under condition two. Debt Instrument Prepayment Premium Percent Of Outstanding Principal Condition Two Prepayment premium, percent of principal, if prepaid during the second year Represents the prepayment premium due, as a percent of the outstanding principal, if prepayment occurs under condition three. Debt Instrument, Prepayment Premium, Percent of Outstanding Principal, Condition Three Prepayment premium, percent of principal, if prepaid after third year Represents the prepayment premium due, as a percent of the outstanding principal, if prepayment occurs under condition three. Debt Instrument Prepayment Premium Percent Of Outstanding Principal Condition Three Prepayment premium, percent of principal, if prepaid after second year The amount of loan that has been expired due to non satisfaction of conditions. Amount of Borrowing Facility Expired Amount of borrowing facility expired Debt Instrument, Interest Rate, Stated Percentage Base interest rate Interest Expense, Debt, Excluding Amortization Interest expense Amortization of Financing Costs Amortization of debt issuance costs Long-term Debt, Gross Total principal payments outstanding Total Outstanding Debt Amount of accreted liability of final payment fee. DebtInstrument, Accreted Liability of Final Payment Fee Add: accreted liability of final payment fee Debt Instrument, Unamortized Discount, Noncurrent Less: unamortized debt discount, long-term Amount, after noncurrent portion of unamortized (discount) premium and debt issuance costs, of long-term debt. Includes, but not limited to, notes payable, bonds payable, debentures, mortgage loans and commercial paper. Excludes capital lease obligations. Long-term Debt Current, Net of Noncurrent Debt Discount Less: current portion of long-term debt Current portion of long-term debt Debt Instrument, Unamortized Discount, Current Current portion of unamortized debt discount Long-term Debt, Maturities, Repayments of Principal, Remainder of Fiscal Year 2020 Long-term Debt, Maturities, Repayments of Principal in Year Two 2021 Long-term Debt, Maturities, Repayments of Principal in Year Three 2022 Long-term Debt, Maturities, Repayments of Principal in Year Four 2023 Earnings Per Share, Basic and Diluted [Abstract] Basic and diluted net loss per common share: Schedule of Antidilutive Securities Excluded from Computation of Earnings Per Share [Table] Antidilutive Securities [Axis] Antidilutive Securities Name [Domain] Antidilutive Securities, Name [Domain] Employee Stock Option [Member] Stock Options Warrant [Member] Warrants