Document and Entity Information Statement [Table] Statement [Line Items] Statement Entity Registrant Name Entity Central Index Key Document Type Document Period End Date Amendment Flag Current Fiscal Year End Date Entity Well-known Seasoned Issuer Entity Voluntary Filers Entity Current Reporting Status Entity Filer Category Entity Public Float Entity Common Stock, Shares Outstanding Document Fiscal Year Focus Document Fiscal Period Focus Consolidated Balance Sheets Assets [Abstract] Assets Assets, Current [Abstract] Current assets: Cash and Cash Equivalents, at Carrying Value Cash and cash equivalents at end of period Cash and cash equivalents at beginning of period Cash and cash equivalents Available-for-sale Securities, Current Marketable securities Prepaid Expense and Other Assets, Current Prepaid expenses and other current assets Assets, Current Total current assets Property, Plant and Equipment, Net Property and equipment, net Assets Total assets Liabilities and Equity [Abstract] Liabilities and Stockholders' Equity Liabilities, Current [Abstract] Current liabilities: Accounts Payable, Current Accounts payable Accrued Liabilities, Current Accrued expenses Liabilities, Current Total current liabilities Liabilities Total liabilities Stockholders' Equity Attributable to Parent [Abstract] Stockholders' equity: Preferred Stock, Value, Issued Preferred stock, par value $0.0001 per share authorized: 5,000,000 shares at December 31, 2017 and December 31, 2016; 1,969,797 and no shares issued and outstanding at December 31, 2017 and December 31, 2016, respectively Common Stock, Value, Issued Common stock, par value $0.0001 per share authorized: 200,000,000 at December 31, 2017 and December 31, 2016, respectively; 14,227,634 and 11,951,866 shares issued and outstanding at December 31, 2017 and December 31, 2016, respectively Additional Paid in Capital, Common Stock Additional paid-in-capital Accumulated Other Comprehensive Income (Loss), Net of Tax Accumulated other comprehensive income (loss) Retained Earnings (Accumulated Deficit) Accumulated deficit Stockholders' Equity Attributable to Parent Balance Balance Total stockholders' equity Liabilities and Equity Total liabilities and stockholders' equity Preferred Stock, Par or Stated Value Per Share Preferred stock, par value (in dollars per share) 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 (in dollars per share) Common Stock, Shares Authorized Common stock, shares authorized Common Stock, Shares, Issued Balance (in shares) Balance (in shares) Common stock, shares issued Common stock received Common Stock, Shares, Outstanding Common stock, shares outstanding Shares outstanding Consolidated Statements of Operations Costs and Expenses [Abstract] Operating expenses: Research and Development Expense (Excluding Acquired in Process Cost) Research and development General and Administrative Expense General and administrative Operating Expenses Total operating expenses Operating Income (Loss) Loss from operations Interest Expense Interest expense Interest Income, Operating Interest income Other Income Other income Net Income (Loss) Available to Common Stockholders, Basic Net loss Net loss Net loss Net Loss Earnings Per Share [Abstract] Net loss per common share: Earnings Per Share, Basic and Diluted Basic and diluted net loss per common share (in dollars per share) Weighted Average Number of Shares Outstanding, Basic and Diluted Basic and diluted weighted average number of common shares outstanding Consolidated Statements of Comprehensive Loss Other Comprehensive Income (Loss), Net of Tax, Portion Attributable to Parent [Abstract] Other comprehensive income (loss): Other Comprehensive Income (Loss), Available-for-sale Securities Adjustment, Net of Tax, Portion Attributable to Parent Unrealized loss on marketable securities Comprehensive Income (Loss), Net of Tax, Attributable to Parent Comprehensive loss Consolidated Statements of Stockholders' Equity Equity Components [Axis] Equity Component [Domain] Equity Component [Domain] Common Stock [Member] Common stock Additional Paid In Capital [Member] Additional paid-in Capital Accumulated Other Comprehensive Income [Member] Accumulated other comprehensive income (loss) Retained Earnings [Member] Accumulated deficit Increase (Decrease) in Stockholders' Equity [Roll Forward] Increase (Decrease) in Stockholders' Equity Amount of increase in additional paid in capital (APIC) resulting from a related party debt restructuring. Adjustments to Additional Paid in Capital, Related Party Debt Restructuring Related party debt restructuring Adjustments to Additional Paid in Capital, Convertible Debt with Conversion Feature Conversion of convertible notes and related accrued interest to common stock Number of shares adjusted regarding to conversion of convertible debt. Adjustment of Common Stock Shares Related to Conversion of Convertible Debt Conversion of convertible notes and related accrued interest to common stock (in shares) Stock Issued During Period, Value, Restricted Stock Award, Forfeitures Retirement of restricted stock Stock Issued During Period, Shares, Restricted Stock Award, Forfeited Retirement of restricted stock (in shares) Stock Issued During Period, Value, Acquisitions Acquisition of Synta Stock Issued During Period, Shares, Acquisitions Acquisition of Synta (in shares) Stock Issued During Period, Value, Issued for Services Issuance of shares to financial advisors in connection with Merger Stock Issued During Period, Shares, Issued for Services Issuance of shares to financial advisors in connection with Merger (in shares) Stock Issued During Period, Value, Restricted Stock Award, Gross Issuance of restricted common shares Stock Issued During Period, Shares, Restricted Stock Award, Gross Issuance of restricted common shares (in shares) Stock Issued During Period, Value, New Issues Value of shares sold by the entity Issuance of common and preferred shares in equity offering, net of transaction costs Stock Issued During Period, Shares, New Issues Number of shares sold by the entity Issuance of common and preferred shares in equity offering, net of transaction costs ( in shares) Adjustments to Additional Paid in Capital, Share-based Compensation, Stock Options, Requisite Service Period Recognition Compensation expense related to stock options for services Consolidated Statements of Cash Flows Net Cash Provided by (Used in) Operating Activities, Continuing Operations [Abstract] Cash flows from operating activities: Net Income (Loss), Including Portion Attributable to Noncontrolling Interest Net loss Adjustments 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: Interest on related party debt paid other than in cash for example by issuing additional debt securities. As a noncash item, it is added to net income when calculating cash provided by or used in operations using the indirect method. Paid-in-Kind Interest, Related Party Debt PIK interest expense on convertible promissory notes payable - related parties Share-based Compensation Stock-based compensation expense The aggregate amount of other noncash, equity-based employee remuneration. As noncash, this element is an add back when calculating net cash generated by operating activities using the indirect method. Other Share Based Compensation Other share based compensation Depreciation, Depletion and Amortization Depreciation and amortization expense Increase (Decrease) in Operating Capital [Abstract] Changes in operating assets and liabilities: Increase (Decrease) in Accounts Receivable, Related Parties Accounts receivable - related parties Increase (Decrease) in Prepaid Expense and Other Assets Prepaid expenses and other current assets Increase (Decrease) in Accounts Payable, Trade Accounts payable Increase (Decrease) in Accrued Liabilities Accrued expense The increase (decrease) during the reporting period in the accrued interest payable to related party disclosed in the statement of cash flows. Increase Decrease In Accrued Interest Related Party Accrued interest - related party Net Cash Provided by (Used in) Operating Activities, Continuing Operations Net cash used in operating activities Net Cash Provided by (Used in) Investing Activities, Continuing Operations [Abstract] Cash flows from investing activities: Proceeds from Divestiture of Businesses Cash received from merger transaction Payments to Acquire Available-for-sale Securities Purchases of marketable securities Proceeds from Maturities, Prepayments and Calls of Available-for-sale Securities Sales and maturities of marketable securities Payments to Acquire Property, Plant, and Equipment Purchases of property and equipment Amount of cash inflow for the sale of long-lived, physical assets used to produce goods and services and not intended for resale and other assets. Proceeds from Sale of Property, Plant, and Equipment And Other Assets Net proceeds from the sale of property, equipment and other assets Proceeds from Restricted Cash, Investing Activities Release of restricted cash Net Cash Provided by (Used in) Investing Activities, Continuing Operations Net cash provided (used) in investing activities Net Cash Provided by (Used in) Financing Activities, Continuing Operations [Abstract] Cash flows from financing activities: The cash inflow from the issuance of common stock, preferred stock, treasury stock, stock options, and other types of equity, net of transaction costs. Proceeds From Issuance Or Sale Of Equity, Net Proceeds from issuance of common and preferred stock, net of transaction costs Net proceeds after deducting commissions and other transactions costs Proceeds from Related Party Debt Cash received Proceeds from convertible notes - related parties Net Cash Provided by (Used in) Financing Activities, Continuing Operations Net cash provided by financing activities Net Cash Provided by (Used in) Continuing Operations Net increase (decrease) in cash and cash equivalents Cash Flow, Noncash Investing and Financing Activities Disclosure [Abstract] Supplemental disclosure of cash flow information: The value of financial instruments that the original debt payable to related party is being converted into in a non cash (or part noncash) transaction. "Part noncash" refers to that portion of the transaction not resulting in cash receipts or cash payments in the period. Related Party Transactions, Debt Conversion Converted Instrument Amount Exchange of related party advances payable for convertible notes Conversion amount The value of related party debt restructured in non-cash investing or financing transactions. Restructuring Of Related Party Debt Related party debt restructuring Capital Expenditures Incurred but Not yet Paid Purchases of property and equipment in accounts payable at period end Organization, Business and Basis of Presentation Organization, Consolidation and Presentation of Financial Statements Disclosure [Text Block] Organization, Business and Basis of Presentation Summary of Significant Accounting Policies Organization, Consolidation, Basis of Presentation, Business Description and Accounting Policies [Text Block] Summary of Significant Accounting Policies Reverse Merger Business Combination Disclosure [Text Block] Reverse Merger Liquidity And Uncertainties Disclosure Abstract Liquidity and Uncertainties Substantial Doubt about Going Concern [Text Block] Liquidity and Uncertainties Cash, Cash Equivalents and Marketable Securities Cash, Cash Equivalents, and Marketable Securities [Text Block] Cash, Cash Equivalents and Marketable Securities N/A Convertible Promissory Notes - Related Parties The entire disclosure of convertible promissory notes related parties. Convertible Promissory Notes Related Parties Disclosure [Text Block] Convertible Promissory Notes - Related Parties n/a Advances Payable-Related Party The entire disclosure for information about the advances payable - related party. Advances Payable To Related Parties Disclosure [Text Block] Advances Payable-Related Party Stockholders' Equity (Deficit) Stockholders' Equity Note Disclosure [Text Block] Stockholders' Equity (Deficit) Stock-based Compensation Disclosure of Compensation Related Costs, Share-based Payments [Text Block] Stock-based Compensation Related Party Transactions Related Party Transactions Disclosure [Text Block] Related Party Transactions Commitments and Contingencies Commitments and Contingencies Disclosure [Text Block] Commitments and Contingencies Income Taxes Income Taxes Income Tax Disclosure [Text Block] Income Taxes Represents information pertaining to recapitalization involving substantial change in a company's capital structure. Recapitalization Entire disclosure text block represents recapitalization involving substantial change in a company's capital structure. Recapitalization [Text Block] Recapitalization Consolidation, Policy [Policy Text Block] Principle of Consolidation Use of Estimates, Policy [Policy Text Block] Use of Estimates Cash and Cash Equivalents, Policy [Policy Text Block] Cash and Cash Equivalents Marketable Securities, Policy [Policy Text Block] Marketable Securities Fair Value of Financial Instruments, Policy [Policy Text Block] Fair Value of Financial Instruments Research and Development Expense, Policy [Policy Text Block] Research and Development Costs Disclosure of accounting policy for patents. Patents [Policy Text Block] Patents Share-based Compensation, Option and Incentive Plans Policy [Policy Text Block] Stock-Based Compensation Income Tax, Policy [Policy Text Block] Income Taxes Comprehensive Income, Policy [Policy Text Block] Comprehensive Loss Earnings Per Share, Policy [Policy Text Block] Basic and Diluted Loss Per Common Share New Accounting Pronouncements, Policy [Policy Text Block] Recent Accounting Pronouncements Schedule of Antidilutive Securities Excluded from Computation of Earnings Per Share [Table Text Block] Summary of the outstanding securities not included in the computation of diluted net loss per common share as their inclusion would be anti-dilutive Schedule of Business Acquisitions, by Acquisition [Table Text Block] Schedule of estimated purchase price Schedule of Recognized Identified Assets Acquired and Liabilities Assumed [Table Text Block] Schedule of allocation of total purchase price to acquired assets and liabilities assumed Cash, Cash Equivalents and Investments [Table Text Block] Summary of cash, cash equivalents and available-for-sale marketable securities Schedule of Share-based Compensation, Stock Options, Activity [Table Text Block] Summary of stock option activity Schedule of Nonvested Restricted Stock Units Activity [Table Text Block] Summary of unvested restricted share activity Tabular disclosure of the allocation of equity-based compensation costs to a given line item on the income statement for the period. This may include the amount of total share-based compensation cost, including the amounts attributable to each share-based compensation plan and any related tax benefits. It includes the reporting line for the costs expensed. Schedule of Share Based Compensation Expense Allocation of Compensation Costs and Recognized Period Costs [Table Text Block] Schedule of stock-based compensation expense Schedule of Unrecognized Compensation Cost, Nonvested Awards [Table Text Block] Schedule of unrecognized stock-based compensation expense Schedule of Deferred Tax Assets and Liabilities [Table Text Block] Schedule of temporary differences that give rise to deferred tax assets and liabilities Schedule of Effective Income Tax Rate Reconciliation [Table Text Block] Schedule of differences between the effective income tax rate and the US statutory rate The amount of costs to secure and defend patents expenses in the statements of operations. Patent Costs Patent expenses The percentage of valuation allowance on the deferred tax assets. Deferred Tax Assets, Percentage Of Valuation Allowance Valuation allowance on deferred tax assets (as a percent) Schedule of Antidilutive Securities Excluded from Computation of Earnings Per Share [Table] Antidilutive Securities [Axis] Antidilutive Securities Name [Domain] Antidilutive Securities, Name [Domain] An arrangement whereby an employee or member of the Board of Directors is entitled to receive in the future, subject to vesting and other restrictions, a number of shares in the entity at a specified price, as defined in the agreement. Employee And Directors Stock Options [Member] Stock options Restricted Stock [Member] Unvested restricted stock Antidilutive Securities Excluded from Computation of Earnings Per Share [Line Items] Anti-dilutive securities Antidilutive Securities Excluded from Computation of Earnings Per Share, Amount Outstanding securities not included in the computation of diluted net loss per common share as their inclusion would be anti-dilutive (in shares) Schedule of Business Acquisitions, by Acquisition [Table] Business Acquisition [Axis] Business Acquisition Acquiree [Domain] Business Acquisition, Acquiree [Domain] Represents information pertaining to merged company. Merger Combined Company [Member] Merged Company Represents Synta Pharmaceuticals Corp. Synta Pharmaceuticals Corp [Member] Synta Pharmaceuticals Corp Represents the information of acquiree company i.e. Madrigal Pharmaceuticals, Inc Madrigal Pharmaceuticals Inc [Member] Madrigal Pharmaceuticals, Inc Business Acquisition [Line Items] Reverse Merger Reverse Merger Agreement Abstract Reverse Merger Agreement [Abstract] Reverse Merger The number of shares issued by the entity for each share of the acquired entity. Number Of Shares Issued For Each Share Of The Acquired Entity Number of shares issued for each share of private Madrigal stock Conversion of Stock, Shares Converted Preferred stock conversion ratio Common stock converted Business Acquisition, Percentage of Voting Interests Acquired Voting interest acquired Stockholders' Equity, Reverse Stock Split Reverse stock split Share-based Compensation Arrangement by Share-based Payment Award, Equity Instruments Other than Options, Nonvested, Number Outstanding at the end of the period (in shares) Outstanding at the beginning of the period (in shares) Unvested restricted common stock Payments to Acquire Businesses, Gross Success fee settled in cash Business Acquisition, Equity Interest Issued or Issuable, Value Assigned Success fee settled for both parties in shares Business Acquisition, Equity Interest Issued or Issuable, Number of Shares Number of shares of the combined company to be owned by Synta stockholders Business Acquisition, Share Price Multiplied by the fair value of Synta common stock Business Combination, Consideration Transferred Purchase price Share Price Closing stock price (in dollars per share) Allocation of the total purchase price to the acquired assets and liabilities assumed Business Combination, Recognized Identifiable Assets Acquired and Liabilities Assumed, Cash and Equivalents Cash, cash equivalents and marketable securities Business Combination, Recognized Identifiable Assets Acquired and Liabilities Assumed, Current Assets, Prepaid Expense and Other Assets Prepaid expenses and other currents assets Business Combination, Recognized Identifiable Assets Acquired and Liabilities Assumed, Property, Plant, and Equipment Property and equipment, net Amount of liabilities incurred for goods and services received that are used in an entity's business and related party payables and other liabilities, assumed at the acquisition date. Business Combination, Recognized Identifiable Assets Acquired and Liabilities Assumed, Current Liabilities, Accounts Payable, Accrued Expenses And Other Liabilities Accounts payable, accrued expenses and other liabilities Business Combination, Recognized Identifiable Assets Acquired and Liabilities Assumed, Capital Lease Obligation Term loans and capital lease obligations Business Combination, Recognized Identifiable Assets Acquired and Liabilities Assumed, Intangible Assets, Other than Goodwill In-process research and development Goodwill Goodwill Business Combination, Recognized Identifiable Assets Acquired, Goodwill, and Liabilities Assumed, Net Net assets acquired Business Combination, Provisional Information, Initial Accounting Incomplete, Adjustment, Property, Plant, and Equipment Measurement period adjustments, Property and equipment, net Business Combination, Provisional Information, Initial Accounting Incomplete, Adjustment, Intangibles Measurement period adjustments, In-process research and development This element represents the amount of any measurement period adjustment (as defined) realized during the reporting period to goodwill acquired in connection with a business combination for which the initial accounting was incomplete. Business Combination, Provisional Information, Initial Accounting Incomplete, Adjustment, Goodwill Measurement period adjustments, Goodwill Gain (Loss) on Disposition of Property Plant Equipment, Excluding Oil and Gas Property and Timber Property Gain or losses on disposition of assets Notes Payable, Related Parties Convertible note issuances outstanding Debt Conversion, Converted Instrument, Shares Issued Debt converted into shares of common stock Represents shares received by plan participants of bonus Or share-based compensation plan in business combination. Business Combination, Change Control Shares Received by Plan Participants In Bonus Or Share Based Compensation Plan Shares received by plan participants in Change in Control Bonus Plan Percentage of awards received by plan participants to the total shares of the entity. Bonus Plan Awards, Percentage Of Awards Received To Entitys Shares Percentage of change in control bonus plan awards to total common shares outstanding Allocated Share-based Compensation Expense Stock-based compensation expense Share-based Compensation Arrangement by Share-based Payment Award, Equity Instruments Other than Options, Grants in Period Granted (in shares) Issued restricted shares (in shares) Share-based Compensation Arrangement by Share-based Payment Award, Options, Grants in Period, Gross Options granted (in shares) Issued options (in shares) Schedule of Investments [Table] Cash and Cash Equivalents [Axis] Restricted Cash And Cash Equivalents Cash And Cash Equivalents [Member] Cash and Cash Equivalents [Domain] Debt securities due within three months of date of purchase issued by domestic or foreign corporate business, banks and other entities with a promise of repayment. Corporate Debt Securities Due Within Three Months [Member] Corporate debt securities due within 3 months of date of purchase Major Types of Debt and Equity Securities [Axis] Major Types Of Debt And Equity Securities [Domain] Major Types of Debt and Equity Securities [Domain] Corporate Debt Securities [Member] Corporate debt securities due within 1 year of date of purchase Measurement Basis [Axis] Portion At Fair Value Fair Value Disclosure [Member] Portion at Fair Value Measurement [Member] Carrying Reported Amount Fair Value Disclosure [Member] Carrying value Estimate Of Fair Value Fair Value Disclosure [Member] Fair value Fair Value, Hierarchy [Axis] Fair Value Measurements Fair Value Hierarchy [Domain] Fair Value Hierarchy [Domain] Fair Value Inputs Level1 [Member] Level 1 Fair Value Inputs Level2 [Member] Level 2 Schedule of Investments [Line Items] Cash, Cash Equivalents and Marketable Securities Cash and Cash Equivalents, Fair Value Disclosure Cash and cash equivalents Represents the maturity period from date of purchase to classify an investment as marketable securities. Maturity Period from Date of Purchase to Classify Investment as Marketable Securities Maturity period from date of purchase to classify an investment as marketable securities Available-for-sale Securities, Amortized Cost Basis Marketable securities, cost Available-for-sale Securities, Accumulated Gross Unrealized Gain, before Tax Marketable securities, unrealized gains Available-for-sale Securities Marketable securities, fair value This item represents the cost of debt and equity securities, which are categorized neither as held-to-maturity nor trading, net of adjustments including accretion, amortization, collection of cash, previous other-than-temporary impairments recognized in earnings, and cash and cash equivalents. Cash, Cash Equivalents, and Short-term Investments, At Cost Total cash, cash equivalents and marketable securities, Cost This item represents the gross unrealized gains for cash and cash equivalents securities, at a point in time, which are categorized neither as held-to-maturity nor trading securities. Cash and Cash Equivalents and Available for Sale Securities, Gross Unrealized Gains Total cash, cash equivalents and marketable securities, Unrealized gains This item represents the gross unrealized losses for cash and cash equivalents securities, at a point in time, which are categorized neither as held-to-maturity nor trading securities. Cash and Cash Equivalents and Available for Sale Securities, Gross Unrealized Losses Cash, cash equivalents and marketable securities, Unrealized losses Cash, Cash Equivalents, and Short-term Investments Total cash, cash equivalents and marketable securities, Fair value Schedule of Related Party Transactions, by Related Party [Table] Related Party Transaction, Rate Interest rate Interest rate of advances from related party The amount of interest payable and waived interest due to related party. Interest Payable And Waived Interest Related Party Current Total accrued and waived interest The amount of interest payable due to related party. Interest Payable Related Party Current Accrued interest The amount of interest payable waived due to related party. Interest Payable Waived Related Party Current Net waived interest recorded as an increase to APIC Accrued interest payable on convertible notes to related party recorded as increase in additional paid-in capital upon conversion of notes Convertible Notes, Related Party, Interest Payable Recorded As Increase In Additional Paid In Capital Accrued interest recorded as increase in APIC upon conversion The number of lenders that exchange advances payable to convertible debt. Related Party Lender Exchanged Advances To Convertible Debt, Number Number of lender that exchanged advances payable to convertible debt Related Party Transaction [Line Items] Related Party Transactions Advances Payable-Related Party The cash outflow related to advances received from related parties. Proceeds From Advances From Related Parties Working capital requirements Schedule of Collaborative Arrangements and Non-collaborative Arrangement Transactions [Table] Collaborative Arrangements and Non-collaborative Arrangement Transactions [Line Items] Stockholders' Equity (Deficit) Represents the number of votes per share that common stockholders are entitled to receive. Common Stock Voting Rights Number Number of votes per share that common stockholders are entitled to receive Sale of Stock [Axis] Sale Of Stock Name Of Transaction [Domain] Sale of Stock [Domain] Over Allotment Option [Member] Additional Shares Represents registered offering. Registered Offering [Member] Registered Offering Counterparty Name [Axis] Repurchase Agreement Counterparty Name [Domain] Counterparty Name [Domain] Represents Goldman Sachs & Co. Goldman Sachs Co [Member] Goldman Sachs & Co. LLC Type of Arrangement and Non-arrangement Transactions [Axis] Arrangements And Nonarrangement Transactions [Member] Arrangements and Non-arrangement Transactions [Domain] Represents Underwriting agreement. Underwriting Agreement [Member] Underwriting Agreement Period granted to purchase additional shares. Sale of Stock, Period Granted to Purchase Additional Shares Number of days granted to purchase additional shares Shares Issued, Price Per Share Issue price of stock Proceeds from Issuance of Common Stock Net proceeds after deducting commissions and other transactions costs Represents information pertaining to private placement offering to sell its securities Securities Purchase Agreement [Member] Purchase Agreement Number of voting rights of preferred stock. Includes eligibility to vote and votes per share owned. Include also, if any, unusual voting rights. Preferred Stock, Number Of Voting Rights Preferred shares number voting rights Represent of Cowen & Co. LLC Member. Cowen Co. Llc [Member] Cowen & Co. LLC Range [Axis] Range [Member] Range [Domain] Maximum [Member] Maximum Represents information pertaining to at-the-market issuance sales agreement for the sale of the entity's common shares. At The Market Issuance Sales Agreement [Member] At-The-Market Issuance Sales Agreement Value of common stock and preferred stock, debt securities and/or warrants, rights or purchase contracts that remain reserved for future issuances under shelf registration with the Securities and Exchange Commission of the United States. Remaining Securities Under Shelf Registration, Value Remaining reserved amount under shelf registration Represents the maximum aggregate offering price the entity may issue and sell shares of its common stock from time to time, at the entity's option, according to at-the-market issuance sales agreement with third party. Common Stock Aggregate Offering Price Maximum aggregate offering price Represents the percentage of gross proceeds payable as commission during the period. Percentage of Gross Proceeds Payable as Commission Percentage of gross proceeds payable as commission Represents number of days of notice period for termination of sales agreement. Sales Agreement Termination Notice Period Days Notice period of termination of sales agreement Schedule of Share-based Compensation Arrangements by Share-based Payment Award [Table] Award Type [Axis] Share Based Compensation Arrangements By Share Based Payment Award Award Type And Plan Name [Domain] Equity Award [Domain] Share-based Compensation Arrangement by Share-based Payment Award [Line Items] Unrecognized stock-based compensation expense Stock-based compensation expense Share-based Compensation Arrangement by Share-based Payment Award, Expiration Period Expiration period Share-based Compensation Arrangement by Share-based Payment Award, Number of Shares Available for Grant Shares available for future issuance Share-based Compensation Arrangement by Share-based Payment Award, Options, Outstanding [Roll Forward] Shares Share-based Compensation Arrangement by Share-based Payment Award, Options, Outstanding, Number Outstanding at the end of the year (in shares) Outstanding at the beginning of the year (in shares) Share-based Compensation Arrangement by Share-based Payment Award, Options, Forfeitures in Period Options cancelled (in shares) Share-based Compensation Arrangement by Share-based Payment Award, Options, Exercisable, Number Exercisable at the end of the year (in shares) Share-based Compensation Arrangement by Share-based Payment Award, Options, Outstanding, Weighted Average Exercise Price [Abstract] Weighted average exercise price Share-based Compensation Arrangement by Share-based Payment Award, Options, Outstanding, Weighted Average Exercise Price Outstanding at the end of the year (in dollars per share) Outstanding at the beginning of the year (in dollars per share) Share-based Compensation Arrangements by Share-based Payment Award, Options, Grants in Period, Weighted Average Exercise Price Options granted (in dollars per share) Share-based Compensation Arrangements by Share-based Payment Award, Options, Forfeitures in Period, Weighted Average Exercise Price Options cancelled (in dollars per share) Share-based Compensation Arrangement by Share-based Payment Award, Options, Exercisable, Weighted Average Exercise Price Exercisable at the end of the year (in dollars per share) Share Based Compensation Arrangement by Share Based Payment Award, Options Outstanding Weighted Average Remaining Contractual Life [Abstract] Weighted average remaining contractual life (years) Share-based Compensation Arrangement by Share-based Payment Award, Options, Outstanding, Weighted Average Remaining Contractual Term Outstanding at the end of the year Share-based Compensation Arrangement by Share-based Payment Award, Options, Exercisable, Weighted Average Remaining Contractual Term Exercisable at the end of the year Share Based Compensation Arrangement by Share Based Payment Award, Options Outstanding Aggregate Intrinsic Value [Abstract] Aggregate intrinsic value Share-based Compensation Arrangement by Share-based Payment Award, Options, Outstanding, Intrinsic Value Outstanding at the end of the year Share-based Compensation Arrangement by Share-based Payment Award, Options, Exercisable, Intrinsic Value Exercisable at the end of the year Share-based Compensation Arrangement by Share-based Payment Award, Options, Additional Disclosures [Abstract] Additional disclosures Employee Service Share-based Compensation, Cash Received from Exercise of Stock Options Total cash received from stock option exercises Share-based Compensation Arrangement by Share-based Payment Award, Options, Grants in Period, Weighted Average Grant Date Fair Value Weighted-average grant date fair value of options (in dollars per share) Share-based Compensation Arrangement by Share-based Payment Award, Equity Instruments Other than Options, Nonvested, Number of Shares [Roll Forward] Shares Share-based Compensation Arrangement by Share-based Payment Award, Equity Instruments Other than Options, Vested in Period Vested (in shares) Share-based Compensation Arrangement by Share-based Payment Award, Equity Instruments Other than Options, Nonvested, Weighted Average Grant Date Fair Value [Abstract] 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 Outstanding at the end of the period (in dollars per share) Outstanding at the beginning of the period (in dollars per share) Share-based Compensation Arrangement by Share-based Payment Award, Equity Instruments Other than Options, Vested in Period, Weighted Average Grant Date Fair Value Vested (in dollars per share) Represents information pertaining to change in control bonus plan awards. Change In Control Bonus Plan [Member] Change in control bonus plan Income Statement Location [Axis] Income Statement Location [Domain] Income Statement Location [Domain] Research And Development Expense [Member] Research and development General And Administrative Expense [Member] General and administrative Employee Stock Option [Member] Stock options Employee Service Share-based Compensation, Nonvested Awards, Compensation Cost Not yet Recognized Unrecognized stock compensation expense Employee Service Share-based Compensation, Nonvested Awards, Compensation Cost Not yet Recognized, Period for Recognition Weighted average remaining period (in years) Interest Expense, Related Party Interest expense incurred on debt from related parties Represents the period of of notice to be provided by the reporting entity for terminating the consulting agreement. Related Party Transaction, Period Of Prior Notice For Termination Of Agreement Period of notice for termination of consulting agreement Related Party Transaction, Expenses from Transactions with Related Party Consulting fees paid Schedule of Long-term Debt Instruments [Table] Debt Instrument [Line Items] Commitments and Contingencies The amount of future milestone payments remaining to be paid under the agreement. Remaining Milestone Payments Remainder of future milestone payments Licenses Revenue Licensed product sales Operating Loss Carryforwards [Table] Income Tax Authority [Axis] Income Tax Authority [Domain] Income Tax Authority [Domain] Domestic Country [Member] Federal State And Local Jurisdiction [Member] State Operating Loss Carryforwards [Line Items] Income Taxes Operating Loss Carryforwards Net operating loss Tax Credit Carryforward [Table] Tax Credit Carryforward [Axis] Tax Credit Carryforward Name [Domain] Tax Credit Carryforward, Name [Domain] Research [Member] Research and development carryforward Tax Credit Carryforward [Line Items] Income Taxes Tax Credit Carryforward, Amount Research and development tax credit carryforwards Valuation Allowance [Table] Valuation Allowance, Deferred Tax Asset, Change in Amount Increase in valuation allowance Unrecognized Tax Benefits Liability for uncertain tax positions Income Tax Examination, Penalties and Interest Expense Income tax related interest and penalties Effective Income Tax Rate Reconciliation, at Federal Statutory Income Tax Rate, Percent Federal income tax rate (as a percent) Amount of income tax expense for remeasurement of deferred tax asset from change in tax rate pursuant to Tax Cuts and Jobs Act of 2017. Tax Cuts and Jobs Act of 2017, Change in Tax Rate, Deferred Tax Asset, Income Tax Expense Reduction in deferred tax assets Amount of reasonable estimate for income tax expense (benefit) from effect of Tax Cuts and Jobs Act of 2017 for which accounting for tax effect is incomplete. Tax Cuts and Jobs Act of 2017, Incomplete Accounting, Provisional Income Tax Expense (Benefit) Amount of provision recorded Components of Deferred Tax Assets and Liabilities [Abstract] Significant portions of deferred tax assets and deferred tax liabilities Deferred Tax Assets, Net Current [Abstract] Deferred Tax Liabilities Amount of deferred tax liability attributable to taxable temporary differences from share-based compensation. Deferred Tax Liabilities, Tax Deferred Expense, Compensation and Benefits, Share-based Compensation Cost Stock Compensation Deferred Tax Liabilities, Unrealized Gains on Trading Securities Unrealized Gains on Investments Deferred Tax Liabilities, Gross Total Deferred Tax Liabilities Deferred Tax Assets Net Non-Current [Abstract] Deferred Tax Assets Deferred Tax Assets, Charitable Contribution Carryforwards Charitable Contributions Deferred Tax Assets, Tax Deferred Expense, Reserves and Accruals, Accrued Liabilities Accrued Expenses Deferred Tax Assets, Tax Deferred Expense, Compensation and Benefits, Share-based Compensation Cost Stock Compensation Deferred Tax Assets, Goodwill and Intangible Assets Intangibles Deferred Tax Assets, Unrealized Losses on Trading Securities Unrealized Loss on Investment Deferred Tax Assets, Operating Loss Carryforwards Net Operating Losses Amount before allocation of valuation allowances of deferred tax asset attributable to deductible temporary differences from research and development costs. Deferred Tax Assets, Deferred Expense, Capitalized Research and Development Costs Capitalized R&D Deferred Tax Assets, Tax Credit Carryforwards, Research R&D Credit Deferred Tax Assets, Gross Total deferred tax assets before valuation allowance Deferred Tax Assets, Valuation Allowance Valuation Allowance Deferred Tax Assets, Net of Valuation Allowance Total deferred tax assets Deferred Tax Assets, Net Net deferred tax assets Effective income tax rate reconciliation Effective Income Tax Rate Reconciliation at Federal Statutory Income Tax Rate, Amount Tax benefit at U.S. federal statutory rate Amount of the difference between reported income tax expense (benefit) and expected income tax expense (benefit) computed by applying the domestic federal statutory income tax rates to pretax income (loss) from continuing operations attributable to nondeductible interest expenses. Effective Income Tax Rate Reconciliation, Nondeductible Expense, Interest Expenses, Amount Non-deductible interest expenses Effective Income Tax Rate Reconciliation, Nondeductible Expense, Share-based Compensation Cost, Amount Stock based compensation Amount of the difference between reported income tax expense (benefit) and expected income tax expense (benefit) computed by applying the domestic federal statutory income tax rates to pretax income (loss) from continuing operations attributable to transaction costs. Effective Income Tax Rate Reconciliation, Transaction Costs, Amount Transaction Costs Effective Income Tax Rate Reconciliation, Change in Enacted Tax Rate, Amount Effect of tax reform, change in federal tax rate Effective Income Tax Rate Reconciliation, Nondeductible Expense, Other, Amount Other Nondeductible Expenses Effective Income Tax Rate Reconciliation, State and Local Income Taxes, Amount State income taxes benefit before valuation allowance, net of federal benefit Effective Income Tax Rate Reconciliation, Change in Deferred Tax Assets Valuation Allowance, Amount Increase in domestic valuation allowance Effective Income Tax Rate Reconciliation, Tax Credit, Research, Amount Research and development credit Effective Income Tax Rate Reconciliation, Other Reconciling Items, Amount Other adjustments Income Tax Expense (Benefit) Income tax expense (benefit) Restructuring Cost and Reserve [Line Items] Recapitalization Preferred Stock [Member] Preferred stock Legal Entity [Axis] Entity [Domain] Entity [Domain] Title of Individual [Axis] Title Of Individual With Relationship To Entity [Domain] Relationship to Entity [Domain] Represents stockholders of the entity. Stockholders [Member] Stockholders Debt Instrument [Axis] Debt Instrument Name [Domain] Debt Instrument, Name [Domain] Convertible Notes Payable [Member] Convertible Promissory Notes Management [Member] Chief Executive Officer, Chief Medical Officer and Executive Vice President, and Chief Financial Officer and Senior Vice President Cash [Member] Cash Money Market Funds [Member] Money market funds Debt Conversion Description [Axis] Debt Conversion Name [Domain] Debt Conversion, Name [Domain] Represents information pertaining to amended and restated March 1, 2016 Convertible Promissory Notes Payable. Amended And Restated March12016 Convertible Promissory Notes Payable [Member] Amended And Restated March 1, 2016 Notes Related Party [Axis] Related Party [Domain] Related Party [Domain] Represents information pertaining to Lender D. Lender D [Member] Lender D Class of Stock [Axis] Class Of Stock [Domain] Class of Stock [Domain] Series A preferred stock that may be exchanged into common shares or other types of securities at the owner's option. Convertible Series Preferred Stock [Member] Series A Convertible Preferred Stock Private Placement [Member] Private Placement Offering Represents information pertaining to former Chief Executive Officer. Former Chief Executive Officer [Member] Former CEO Related Party Transaction [Axis] Related Party Transaction [Domain] Related Party Transaction [Domain] Represents information pertaining to the consulting agreement with the former CEO of the reporting entity. Consulting Agreement [Member] Consulting Agreement Represents information pertaining to Research, Development and Commercialization Agreement with Hoffmann-La Roche ("Roche") which grants a sole and exclusive license to develop, use, sell, offer for sale and import any Licensed Product as defined by the agreement. Research Development And Commercialization Agreement [Member] Research, Development and Commercialization Agreement Represents information pertaining to Hoffman-La Roche. Hoffman La Roche [Member] Hoffmann-La Roche ("Roche") Scenario [Axis] Scenario Unspecified [Domain] Scenario, Unspecified [Domain] Scenario Forecast [Member] Forecast