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Ltd [Member] Represents the information pertaining to Kyowa Kirin Co., Ltd. Number of shares granted Granted (shares) Share-based Compensation Arrangement by Share-based Payment Award, Equity Instruments Other than Options, Grants in Period Loan agreement covenant, net product revenue as percentage of outstanding loan balance, minimum Loan Agreement, Covenant, Net Product Revenue As Percentage Of Outstanding Loan Balance, Minimum Loan Agreement, Covenant, Net Product Revenue As Percentage Of Outstanding Loan Balance, Minimum Summary of significant accounting policies New Accounting Pronouncements or Change in Accounting Principle [Line Items] Concentration risk (percent) Concentration Risk, Percentage Preferred stock, $0.0001 par value; 5,000,000 shares authorized; no shares issued and outstanding as of December 31, 2021 and December 31, 2020, respectively. Preferred Stock, Value, Issued Property and Equipment Property, Plant and Equipment, Policy [Policy Text Block] Proceeds from issuance of common stock under equity incentive and stock purchase plans Proceeds, Issuance of Shares, Share-based Payment Arrangement, Including Option Exercised Amortization and depreciation Deferred Tax Assets, Amortization and Depreciation Amount before allocation of valuation allowances of deferred tax asset attributable to deductible temporary differences from amortization and depreciation. 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Additions based on tax positions related to current year Unrecognized Tax Benefits, Increase Resulting from Current Period Tax Positions Components of the provision for income taxes Income Tax Expense (Benefit), Continuing Operations [Abstract] Total liabilities and stockholders’ equity Liabilities and Equity Other Effective Income Tax Rate Reconciliation, Other Adjustments, Percent Deferred revenue Beginning balance Ending balance Contract with Customer, Liability, Current 2026 Lessee, Operating Lease, Liability, to be Paid, Year Five Scenario [Axis] Scenario [Axis] Proceeds from maturities and redemptions of investments Proceeds from Sale and Maturity of Debt Securities, Available-for-sale Options exercised (in dollars per share) Share-based Compensation Arrangements by Share-based Payment Award, Options, Exercises in Period, Weighted Average Exercise Price Potential increase to shares reserved for inclusion of forfeited or unexercised options from prior plan Increase In Shares Reserved For Issuance, Maximum Shares To Be Issued Upon Inclusion Of Forfeited Or Unexercised Options Increase In Shares Reserved For Issuance, Maximum Shares To Be Issued Upon Inclusion Of Forfeited Or Unexercised Options Lease Arrangements [Axis] Lease Arrangements [Axis] Lease Arrangements Lessee, Lease, Description [Table] Lessee, Lease, Description [Table] Concentration Risk [Line Items] Concentration Risk [Line Items] Liabilities and stockholders’ equity Liabilities and Equity [Abstract] Derivative liability for exit fee Exit fee derivative liability Derivative Financial Instruments, Liabilities [Member] Fosun Pharma Fosun [Member] Represents information pertaining to Fosun. 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Net Loss Per Share Earnings Per Share [Text Block] Operating expenses: Operating Expenses [Abstract] Entity Interactive Data Current Entity Interactive Data Current Short-term investments: Debt Securities, Available-for-Sale, Fair Value to Amortized Cost, after Allowance for Credit Loss [Abstract] Cash and Cash Equivalents [Domain] Cash and Cash Equivalents [Domain] Waltham facility Facility Two, Waltham Massachusetts [Member] Facility Two, Waltham Massachusetts Issuance of common stock upon exercise of options Stock Issued During Period, Value, Stock Options Exercised Minimum Minimum [Member] Error Correction, Type [Axis] Error Correction, Type [Axis] 2022 Term Loan Term Loan 2022 [Member] Term Loan 2022 2023 Lessee, Operating Lease, Liability, to be Paid, Year Two Hong Kong HONG KONG Schedule of Revenues from External Customers and Long-Lived Assets [Table] Schedule of Revenues from External Customers and Long-Lived Assets [Table] Liabilities, fair value Financial and Nonfinancial Liabilities, Fair Value Disclosure Long-term investments: Long-term Investments [Abstract] Preferred stock, shares authorized Preferred Stock, Shares Authorized Balance at beginning of year Balance at end of year Unrecognized Tax Benefits Income Tax Authority [Domain] Income Tax Authority [Domain] Gross deferred tax assets Deferred Tax Assets, Gross Entity Common Stock, Shares Outstanding Entity Common Stock, Shares Outstanding Short-term investments, Gross Unrealized Gains Debt Securities, Available-for-sale, Accumulated Gross Unrealized Gain, before Tax Shares available for grant, effect of authorized (shares) Share-Based Compensation Arrangement By Share Based Payment Award, Number Of Shares Available For Grant, Increase Due To Authorized In Period Share based compensation arrangement by share based payment award number of shares available for grant options authorized. Entity Address, State or Province Entity Address, State or Province U.S. treasury notes US Treasury Notes Securities [Member] Current liabilities: Liabilities, Current [Abstract] U.S. government-sponsored agency bonds US Government Corporations and Agencies Securities [Member] Issuance of common stock Stock Issued During Period, Value, New Issues Shares available for grant, effect of shares issued for services (shares) Share-Based Compensation Arrangement By Share Based Payment Award, Number Of Shares Available For Grant, Decrease Due To Stock Issued For Services In Period Share-Based Compensation Arrangement By Share Based Payment Award, Number Of Shares Available For Grant, Decrease Due To Stock Issued For Services In Period Potential increase in shares reserved as a percentage of shares outstanding Increase In Shares Reserved For Issuance, Option For Annual Increase As Percentage Of Shares Outstanding Increase In Shares Reserved For Issuance, Option For Annual Increase As Percentage Of Shares Outstanding Operating Lease liabilities Increase (Decrease) in Operating Lease Liability General and administrative General and Administrative Expense Revision of Prior Period [Axis] Revision of Prior Period [Axis] Restructuring Plan [Domain] Restructuring Plan [Domain] Borrowings Debt Disclosure [Text Block] Balance (in shares) Balance (in shares) Shares, Outstanding Schedule of Components of Provision for Income Taxes Schedule of Components of Income Tax Expense (Benefit) [Table Text Block] Options exercisable (in dollars per share) Share-based Compensation Arrangement by Share-based Payment Award, Options, Exercisable, Weighted Average Exercise Price Equity Incentive Plans Share-based Payment Arrangement [Text Block] Level 3 Fair Value, Inputs, Level 3 [Member] Leases Lessee, Leases [Policy Text Block] Uncharged license fee reclassified to accounts payable Uncharged License Fee Reclassified To Accounts Payable Uncharged License Fee Reclassified To Accounts Payable Accounting Policies [Abstract] Accounting Policies [Abstract] Options issued and outstanding (in years) Share-based Compensation Arrangement by Share-based Payment Award, Options, Outstanding, Weighted Average Remaining Contractual Term Derivative Instrument [Axis] Derivative Instrument [Axis] Minimum tax credit carryforwards Minimum Tax Credit Carryforward [Member] Minimum Tax Credit Carryforward [Member] Issuance of common stock (in shares) Common stock sold and issued (in shares) Stock Issued During Period, Shares, New Issues Term of agreement Term Of Agreement Term of agreement. Total operating lease liabilities Operating Lease, Liability Document Transition Report Document Transition Report Schedule of Error Corrections and Prior Period Adjustment Restatement [Table] Schedule of Error Corrections and Prior Period Adjustment Restatement [Table] Common stock, $0.0001 par value; 300,000,000 shares authorized; 130,182,535 and 93,599,975 shares issued and outstanding as of December 31, 2021 and December 31, 2020, respectively. Common Stock, Value, Issued Other income, net Nonoperating Income (Expense) Average Remaining Vesting Period (years) Share-based Payment Arrangement, Nonvested Award, Cost Not yet Recognized, Period for Recognition Nonvested balance, beginning (in dollars per share) Nonvested balance, ending (in dollars per share) Share-based Compensation Arrangement by Share-based Payment Award, Equity Instruments Other than Options, Nonvested, Weighted Average Grant Date Fair Value Number of options to extend Lessee, Operating Lease, Number Of Renewal Options Lessee, Operating Lease, Number Of Renewal Options Basis of Presentation Basis of Accounting, Policy [Policy Text Block] Commitments and contingencies Commitments and Contingencies Future payment obligations Long-term Debt, Fiscal Year Maturity [Abstract] Subsequent Event [Table] Subsequent Event [Table] Leases Lessee, Operating Leases [Text Block] XuanZhu Xuanzhu [Member] Represents the information pertaining to XuanZhu. Accumulated other comprehensive income (loss) Accumulated Other Comprehensive Income (Loss), Net of Tax Entity Emerging Growth Company Entity Emerging Growth Company Prepayment premium (as a percent) Debt Instrument, Prepayment Fee, Percentage The percentage of fee payable on prepayment of debt. Net proceeds from loan Proceeds from loan payable, net of issuance costs Proceeds from Debt, Net of Issuance Costs Short-term available-for-sale securities contractual maturities, maximum Available-For-Sale Securities, Debt Securities, Current, Contractual Maturities, Maximum Available-For-Sale Securities, Debt Securities, Current, Contractual Maturities, Maximum Cost of revenue, amount paid Payments of Uncharged License Fees Represents the cash outflow from payments of uncharged license fees. ICFR Auditor Attestation Flag ICFR Auditor Attestation Flag Schedule of Valuation Assumptions for Stock Options Schedule of Share-based Payment Award, Stock Options, Valuation Assumptions [Table Text Block] Threshold percentage of net sales for tiered royalties Threshold Percentage of Sales For Tiered Royalties Represents the threshold percentage of net sales for tiered royalties. Cash and cash equivalents: Cash and Cash Equivalents, at Carrying Value [Abstract] Antidilutive Securities, Name [Domain] Antidilutive Securities, Name [Domain] 2020 Open Market Sales Agreement Open Market Sales Agreement 2020, At The Market Offering [Member] Open Market Sales Agreement 2020, At The Market Offering PRSUs Performance-based restricted stock units Performance Based Restricted Stock Units [Member] This member stands for performance-based restricted stock units. Auditor Name Auditor Name Cover [Abstract] Cover [Abstract] Revenues from External Customers and Long-Lived Assets [Line Items] Revenues from External Customers and Long-Lived Assets [Line Items] Total operating expenses Costs and Expenses Schedule of Revenue by Geographic Areas Revenue from External Customers by Geographic Areas [Table Text Block] Class of Stock [Axis] Class of Stock [Axis] Cash and Cash Equivalents Cash and Cash Equivalents, Policy [Policy Text Block] Collaborative Arrangement and Arrangement Other than Collaborative [Axis] Collaborative Arrangement and Arrangement Other than Collaborative [Axis] Uncharged license fee Uncharged License Fee, Current The amount of uncharged license fee classified as current. Imputed interest expenses Lessee, Operating Lease, Liability, Undiscounted Excess Amount Exit fee, term (in years) Loan Agreement, Exit Fee, Term Loan Agreement, Exit Fee, Term Subsidiary or Equity Method Investee, Sale of Stock by Subsidiary or Equity Investee [Table] Subsidiary or Equity Method Investee, Sale of Stock by Subsidiary or Equity Investee [Table] Accrued sales and marketing expenses Accrued Sales And Marketing Expenses Amount of accrued sales and marketing expenses. Income Tax Authority [Axis] Income Tax Authority [Axis] Proceeds from underwritten public offering, net of issuance costs Sale of Stock, Consideration Received on Transaction Prepaid expenses and other current assets Prepaid Expense and Other Assets, Current Comprehensive loss: Comprehensive Income (Loss), Net of Tax, Attributable to Parent [Abstract] Financial Instrument [Axis] Financial Instrument [Axis] Total revenues Revenue Revenue from Contract with Customer, Excluding Assessed Tax Fosun Pharma Shanghai Fosun Pharmaceutical Industrial Development [Member] Represents Shanghai Fosun Pharmaceutical Industrial Development. Stock-based compensation Deferred Tax Assets, Tax Deferred Expense, Compensation and Benefits, Share-based Compensation Cost Proceeds from issuance of common stock upon private placement, net of issuance costs Proceeds from Issuance of Private Placement Current: Current Income Tax Expense (Benefit), Continuing Operations [Abstract] Knight Agreement License Agreement Development Commercialization Distribution In Canada [Member] Agreement for the development, commercialization and distribution fo tenapanor in Canada. The Knight Agreement. Stock options Options to purchase common stock Share-based Payment Arrangement, Option [Member] Fair Value Hierarchy and NAV [Axis] Fair Value Hierarchy and NAV [Axis] Issuance of common stock for services Stock Issued During Period, Value, Issued for Services Tax credits Effective Income Tax Rate Reconciliation, Tax Credit, Percent Number of Shares Purchased Employee Stock Purchase Plan, Shares Purchased [Roll Forward] Employee Stock Purchase Plan, Shares Purchased Common Stock Common Stock [Member] Variable Rate [Axis] Variable Rate [Axis] Loss from operations Operating Income (Loss) Property, Plant and Equipment [Table] Property, Plant and Equipment [Table] Debt Securities, Available-for-sale [Line Items] Debt Securities, Available-for-sale [Line Items] Current portion of operating lease liability Current portion of lease liabilities Current portion of operating lease liability Operating Lease, Liability, Current Short-term investments, Gross Unrealized Losses Debt Securities, Available-for-sale, Accumulated Gross Unrealized Loss, before Tax Organization and Basis of Presentation Organization, Consolidation, Basis of Presentation, Business Description and Accounting Policies [Text Block] Collaboration and Licensing Agreements Collaborative Arrangement Disclosure [Text Block] ESPP ESPP shares issuable Employee Stock Purchase Plan [Member] Employee Stock Purchase Plan [Member] Document Fiscal Year Focus Document Fiscal Year Focus Property, Plant and Equipment [Abstract] Property, Plant and Equipment [Abstract] Stock-based compensation Share-based Payment Arrangement, Noncash Expense Restructuring Restructuring and Related Activities Disclosure [Text Block] Variable Rate [Domain] Variable Rate [Domain] Additional Paid-In Capital Additional Paid-in Capital [Member] Cash and cash equivalents Cash and cash equivalents Cash and Cash Equivalents, at Carrying Value Depreciation expense Depreciation Weighted-average share price (in dollars per share) Sale Of Stock, Weighted-Average Price Per Share Sale Of Stock, Weighted-Average Price Per Share Long-term Debt, Type [Domain] Long-term Debt, Type [Domain] Cash and Cash Equivalents [Abstract] Cash and Cash Equivalents [Abstract] Notice period for impacted employees cash payments and benefits Restructuring And Related Cost, Impacted Employees Term For Cash Payments And Benefits Restructuring And Related Cost, Impacted Employees Term For Cash Payments And Benefits Cost of revenue, aggregate amount recognized Cost Of Revenue, Aggregate Amount Recognized Cost of revenue, aggregate amount recognized. AstraZeneca Termination Agreement AstraZeneca Termination Agreement [Member] AstraZeneca Termination Agreement Accrued and other liabilities Increase (Decrease) in Accrued Liabilities Arrangements and Non-arrangement Transactions [Domain] Collaborative Arrangement and Arrangement Other than Collaborative [Domain] Schedule of Restricted Stock Units Activity Share-based Payment Arrangement, Restricted Stock Unit, Activity [Table Text Block] Fremont facility Facility, Fremont California [Member] Facility, Fremont California Issuance of common stock for services Stock Issued Purchases of property and equipment Payments to Acquire Property, Plant, and Equipment Other Other Liabilities, Current Maximum Maximum [Member] Share-based Payment Arrangement [Abstract] Share-based Payment Arrangement [Abstract] Total liabilities Liabilities Unbilled revenue Increase (Decrease) In Unbilled Revenue Amount of increase or decrease in unbilled revenue. 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Summary of Undiscounted Cash Payment Obligations for Operating Lease Liabilities Lessee, Operating Lease, Liability, Maturity [Table Text Block] Total stockholders’ equity Balance Balance Stockholders' Equity Attributable to Parent Geographic Information and Concentrations Geographic Information And Concentrations [Text Block] The entire disclosure on geographic information and concentrations. Issuance of common stock for services (in shares) Issuance of common stock for services (in shares) Stock Issued During Period, Shares, Issued for Services Existence of option to extend Lessee, Operating Lease, Existence of Option to Extend [true false] Net operating loss carryforwards Operating Loss Carryforwards Common stock, shares issued Common Stock, Shares, Issued Preferred stock, shares issued Preferred Stock, Shares Issued City Area Code City Area Code Options exercisable Share-based Compensation Arrangement by Share-based Payment Award, Options, Exercisable, Intrinsic Value Additional planned reduction in workforce Restructuring And Related Cost, Planned Number Of Positions Eliminated Restructuring And Related Cost, Planned Number Of Positions Eliminated Entity Address, City or Town Entity Address, City or Town Product supply revenue Product Supply Revenue [Member] Product Supply Revenue Office space area added (sq ft) Area of Real Estate Property Added During Period Area of Real Estate Property Added During Period Exit fee (percent) Exit Fee, Percentage Exit Fee, Percentage Estimated useful lives Property, Plant and Equipment, Useful Life Stockholders’ equity: Stockholders' Equity Attributable to Parent [Abstract] Schedule of Reconciliation of Unrecognized Tax Benefits Schedule of Unrecognized Tax Benefits Roll Forward [Table Text Block] Income Tax Authority, Name [Domain] Income Tax Authority, Name [Domain] Concentration of Credit Risk Concentration Risk, Credit Risk, Policy [Policy Text Block] Offering sales commission (percent) Stock Issuance Cost, Commission, Percent Percentage of commission given on gross proceeds from sale of securities. 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Audit Information [Abstract] Audit Information Collaborative development revenue Collaborative Development [Member] Collaborative Development [Member] Other states Tax Authority, States Other Than California [Member] Tax Authority, States Other Than California Common stock closing price (in dollars per share) Share Price Accumulated deficit Retained Earnings (Accumulated Deficit) RSUs Restricted stock units Restricted Stock Units (RSUs) [Member] Statement of Stockholders' Equity [Abstract] Statement of Stockholders' Equity [Abstract] Final fee due upon maturity, acceleration, prepayment, or termination (percent) Debt Instrument, Fee Due Upon Maturity, Acceleration, Prepayment, Termination, Percentage Debt Instrument, Fee Due Upon Maturity, Acceleration, Prepayment, Termination, Percentage Revision of Prior Period [Domain] Revision of Prior Period [Domain] Issuance of common stock under employee stock purchase plan (in shares) Stock Issued During Period, Shares, Employee Stock Purchase Plans Entity Filer Category Entity Filer Category AstraZeneca Astrazeneca [Member] Represents information pertaining to AstraZeneca. Term of payment of license fee, first installment Term Of Payment Of License Fee, First Installment Term of payment of first installment fee. Other-than-temporary impairment Other-than-temporary Impairment Loss, Debt Securities, Available-for-sale Risk-free interest rate Share-based Compensation Arrangement by Share-based Payment Award, Fair Value Assumptions, Risk Free Interest Rate Fair value analysis, percentage change in probability of occurrence Fair Value Sensitivity Analysis, Change In Probability Of Occurrence, Percentage Fair Value Sensitivity Analysis, Change In Probability Of Occurrence, Percentage 2014 Plan Two Thousand Fourteen Equity Incentive Award Plan [Member] 2014 Equity Incentive Award Plan [Member] Income Statement [Abstract] Income Statement [Abstract] Concentration Risk [Table] Concentration Risk [Table] Entity Registrant Name Entity Registrant Name Number of separate collaborative agreements Number Of Separate Collaborative Agreements Number of separate collaborative agreements. Asset Class [Domain] Asset Class [Domain] Schedule of Employee Stock Purchase Plan Activity Schedule of Share-based Compensation, Employee Stock Purchase Plan, Activity [Table Text Block] Schedule of Changes in Fair Value of Derivative Liability Fair Value, Liabilities Measured on Recurring Basis, Unobservable Input Reconciliation [Table Text Block] XuanZhu Agreement XuanZhu Agreement [Member] XuanZhu Agreement Shares Available for Grant Shares Available For Grant [Roll Forward] Shares Available For Grant Second installment of upfront license fees Collaboration And Licensing Agreements, Upfront License Fees, Second Installment Collaboration And Licensing Agreements, Upfront License Fees, Second Installment Options canceled (in dollars per share) Share-based Compensation Arrangements by Share-based Payment Award, Options, Forfeitures in Period, Weighted Average Exercise Price Provision for income taxes Provision for income taxes Income Tax Expense (Benefit) 2018 Term Loan Term Loan 2018 [Member] Term Loan 2018 Accounts receivable Accounts Receivable, after Allowance for Credit Loss, Current Amendment Flag Amendment Flag Asia Pacific Asia Pacific [Member] Equity Components [Axis] Equity Components [Axis] Schedule of Securities Classified as Cash and Investments Cash, Cash Equivalents and Investments [Table Text Block] Entity Tax Identification Number Entity Tax Identification Number Fair Value Disclosures [Abstract] Fair Value Disclosures [Abstract] Antidilutive Securities [Axis] Antidilutive Securities [Axis] Gross Proceeds Share-Based Compensation Arrangement By Share-Based Payment Award, Employee Stock Purchase Plan, Gross Proceeds The amount of gross proceeds received from shares issued to employees under the plan. Document Fiscal Period Focus Document Fiscal Period Focus Total current assets Assets, Current Concentration Risk Type [Domain] Concentration Risk Type [Domain] Total undiscounted operating lease payments Lessee, Operating Lease, Liability, to be Paid Sale of Stock [Domain] Sale of Stock [Domain] Denominator: Weighted Average Number of Shares Outstanding Reconciliation [Abstract] Forfeited (shares) Share-based Compensation Arrangement by Share-based Payment Award, Equity Instruments Other than Options, Forfeited in Period Fosun Agreement License Agreement Development Commercialization Distribution In China [Member] Agreement for the development, commercialization and distribution of tenapanor in China. The Fosun Agreement. Initial transaction price Collaboration And Licensing Agreements, Initial Transaction Price The amount of initial transaction price. Deferred revenue - non-current Change In Contract With Customer Liability, Noncurrent, Rollforward [Roll Forward] Change In Contract With Customer Liability, Noncurrent, Rollforward Federal Deferred Federal Income Tax Expense (Benefit) 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] Fair Value Debt Securities, Available-for-sale, Fair Value, Fiscal Year Maturity [Abstract] Statement of Financial Position [Abstract] Statement of Financial Position [Abstract] Term Loan A Term Loan 2022 A [Member] Term Loan 2022 A Exit fee, net product revenue threshold Loan Agreement, Exit Fee, Net Product Revenue Threshold Metric, Trailing Six Month Basis, Minimum Loan Agreement, Exit Fee, Net Product Revenue Threshold Metric, Trailing Six Month Basis, Minimum Thereafter Lessee, Operating Lease, Liability, to be Paid, after Year Five Increase due to unbilled prepayments recorded during the period Contract With Customer, Liability, Increase Due To Unbilled Prepayments Recorded Contract With Customer, Liability, Increase Due To Unbilled Prepayments Recorded Prior Period Errors Prior Period Errors [Policy Text Block] Disclosure of accounting policy related to prior period errors. 2017 KKC Agreement License Agreement Development Commercialization Distribution In Japan [Member] Agreement for the development, commercialization and distribution of tenapanor in Japan. The 2017 KKC Agreement. Product and Service [Axis] Product and Service [Axis] Long-Lived Tangible Asset [Domain] Long-Lived Tangible Asset [Domain] Workforce realignment Workforce Realignment [Member] Workforce Realignment Restructuring Plan [Axis] Restructuring Plan [Axis] Preferred stock, par value (in dollars per share) Preferred Stock, Par or Stated Value Per Share Entity Public Float Entity Public Float Documents Incorporated by Reference Documents Incorporated by Reference [Text Block] Amortization of deferred compensation for services Amortization of Deferred Charges Error Correction, Type [Domain] Error Correction, Type [Domain] Weighted-average grant-date estimated fair value of options granted (in dollars per share) Share-based Compensation Arrangement by Share-based Payment Award, Options, Grants in Period, Weighted Average Grant Date Fair Value Long-term investments, Gross Unrealized Gains Long Term Investments, Accumulated Gross Unrealized Gain Long Term Investments, Accumulated Gross Unrealized Gain Equity Component [Domain] Equity Component [Domain] Cost of revenue, aggregate amount paid Payments Of Uncharged License Fees, Aggregate Amount Paid Payments of uncharged license fees, aggregate amount paid. After second anniversary to maturity date Debt Instrument, Redemption, Period Three [Member] 2022 Lessee, Operating Lease, Liability, to be Paid, Year One Shares purchased (shares) Share-based Compensation Arrangement by Share-based Payment Award, Shares Issued in Period 2021 Open Market Sales Agreement Open Market Sales Agreement 2021, At The Market Offering [Member] Open Market Sales Agreement 2021, At The Market Offering Non-cash interest associated with debt discount accretion Amortization of Debt Discount (Premium) Statement [Line Items] Statement [Line Items] Maximum shares to be issued upon exercise of incentive stock options Increase In Shares Reserved For Issuance, Maximum Shares To Be Issued Upon Exercise Of Stock Options Increase In Shares Reserved For Issuance, Maximum Shares To Be Issued Upon Exercise Of Stock Options Shares available for grant, effect of canceled (shares) Share-Based Compensation Arrangement By Share Based Payment Award, Number Of Shares Available For Grant, Increase Due To Canceled In Period Share-Based Compensation Arrangement By Share Based Payment Award, Number Of Shares Available For Grant, Increase Due To Canceled In Period Income Tax Disclosure [Table] Income Tax Disclosure [Table] Income Tax Disclosure [Table] Facilities - right-of-use assets and lease liabilities Assets and Liabilities, Lessee [Abstract] Weighted-Average Exercise Price  per Share Share-based Compensation Arrangement by Share-based Payment Award, Options, Outstanding, Weighted Average Exercise Price [Abstract] Federal Domestic Tax Authority [Member] Short-term investments, Fair Value Debt Securities, Available-for-sale 2019 KKC Agreement Research Collaboration And Option Agreement [Member] Pertaining to the research collaboration and option agreement for research associated with identifying two pre-clinical compounds. The 2019 KKC AGreement. Change in valuation allowance Effective Income Tax Rate Reconciliation, Change in Deferred Tax Assets Valuation Allowance, Percent Counterparty Name [Domain] Counterparty Name [Domain] 2025 Lessee, Operating Lease, Liability, to be Paid, Year Four Office equipment and furniture Office Equipment And Furniture [Member] Office Equipment And Furniture [Member] Debt Disclosure [Abstract] Debt Disclosure [Abstract] Underwritten public offering, including underwriter option Underwritten Public Offering, Including Overallotment, December 2019 [Member] Underwritten Public Offering, Including Overallotment, December 2019 Potential development milestones Collaborative Arrangement, Potential Development Milestones Collaborative Arrangement, Potential Development Milestones Loss before provision for income taxes Income (Loss) from Continuing Operations before Income Taxes, Noncontrolling Interest Level 2 Fair Value, Inputs, Level 2 [Member] Cash and Investments Cash, Cash Equivalents, and Short-term Investments [Text Block] Type of Adoption [Domain] Accounting Standards Update [Domain] Long-Lived Tangible Asset [Axis] Long-Lived Tangible Asset [Axis] Valuation allowance Deferred Tax Assets, Valuation Allowance Subsidiary, Sale of Stock [Line Items] Subsidiary, Sale of Stock [Line Items] Deferred revenue, non-current Beginning balance Ending balance Contract with Customer, Liability, Noncurrent Auditor Location Auditor Location Short-term investments, Cost Debt Securities, Available-for-sale, Amortized Cost Lease Arrangements [Domain] Lease Arrangements [Domain] Lease Arrangements [Domain] Loan payable, net of current portion Loans Payable, Noncurrent Restructuring Cost and Reserve [Line Items] Restructuring Cost and Reserve [Line Items] Purchases of investments Payments to Acquire Short-term Investments Use of Estimates Use of Estimates, Policy [Policy Text Block] Schedule of Computation of Net Loss Per Common Share Schedule of Earnings Per Share, Basic and Diluted [Table Text Block] Options granted (shares) Share-based Compensation Arrangement by Share-based Payment Award, Options, Grants in Period, Gross Asset Class [Axis] Asset Class [Axis] Document Annual Report Document Annual Report Schedule of Stock-Based Compensation Recognized Share-based Payment Arrangement, Expensed and Capitalized, Amount [Table Text Block] Forecast Forecast [Member] Title of 12(b) Security Title of 12(b) Security License fee recognized Collaboration And Licensing Agreements, License Fee The amount of licenses fee recognized during the period. Proceeds from issuance of common stock in At-the-market offering, net of issuance costs Proceeds from issuance of common stock Proceeds from Issuance of Common Stock Total assets Assets Plan Name [Domain] Plan Name [Domain] Board of directors Director [Member] Common stock, shares authorized Common Stock, Shares Authorized Underwritten public offering Underwritten Public Offering [Member] Underwritten Public Offering Cash paid for interest Interest Paid, Excluding Capitalized Interest, Operating Activities Numerator: Net Income (Loss) Attributable to Parent [Abstract] Collaboration partnership concentration risk Collaboration Partnership Concentration Risk [Member] Collaboration Partnership Concentration Risk Geographical [Domain] Geographical [Domain] Weighted Average Remaining Contractual Term Stock Options, Weighted Average Remaining Contractual Term [Abstract] Stock Options, Weighted Average Remaining Contractual Term Principal repayments for loan payable Principal repayment Repayments of Secured Debt Title of Individual [Axis] Title of Individual [Axis] Document Type Document Type Second milestone payment Collaboration And Licensing Agreements, Second Milestone Payment The amount of second milestone payment recognized during the period. Accrued Expenses and Other Current Liabilities Accounts Payable, Accrued Liabilities, and Other Liabilities Disclosure, Current [Text Block] Research and development Research and development Research and Development Expense Products and Services [Domain] Product and Service [Domain] Accrued professional and consulting services Accrued Professional And Consultant Fees Current Accrued professional and consultant fees current. Derivative Contract [Domain] Derivative Contract [Domain] Term of lease extension Lessee, Operating Lease, Renewal Term Short-Term Investments Short Term Investments [Policy Text Block] Short term investments. 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Agreed amount for exit fee upon change of control or regulatory approval Derivative Liability, Notional Amount Fair Value, Recurring and Nonrecurring [Table] Fair Value, Recurring and Nonrecurring [Table] Additional planned reduction in workforce (percent) Restructuring And Related Cost, Planned Number Of Positions Eliminated, Period Percent Restructuring And Related Cost, Planned Number Of Positions Eliminated, Period Percent Summary of Lease Costs Lease, Cost [Table Text Block] Schedule of Long-term Debt Instruments [Table] Schedule of Long-term Debt Instruments [Table] Subsequent Event [Line Items] Subsequent Event [Line Items] Amortized Cost Debt Securities, Available-for-sale, Amortized Cost, Fiscal Year Maturity [Abstract] Geographical [Axis] Geographical [Axis] Tax Credit Carryforward [Axis] Tax Credit Carryforward [Axis] Commercial paper Commercial Paper, Not Included with Cash and Cash Equivalents [Member] Accrued expenses and other current liabilities Accrued expenses and other current liabilities Accrued liabilities and other liabilities Accrued Liabilities and Other Liabilities Less: Unaccreted value of final fee Debt Instrument, Fee Amount Shares used in computing net loss per share - basic Weighted average common shares outstanding - basic Weighted Average Number of Shares Outstanding, Basic Net loss per common share - diluted (in dollars per share) Net loss per share - diluted (in dollars per share) Earnings Per Share, Diluted State State and Local Jurisdiction [Member] Share price (in dollars per share) Sale of Stock, Price Per Share Non-cash lease expense Operating Lease, Right-of-Use Asset, Amortization Expense Knight Knight Therapeutics Inc [Member] Represents information pertaining to Knight Therapeutics Inc. Final fee payment Debt Instrument, Final Fee Payment Debt Instrument, Final Fee Payment Cash paid for income taxes Income Taxes Paid, Net Gross proceeds from sale of stock Proceeds From Issuance Of Common Stock, Gross The gross cash inflow from the additional capital contribution to the entity. 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Collaboration and Licensing Agreements Collaboration and Licensing Agreements [Abstract] Corporate bonds Corporate Debt Securities [Member] Schedule of Reconciliation of Effective Tax Rate Schedule of Effective Income Tax Rate Reconciliation [Table Text Block] Fair Value Measurements Fair Value Disclosures [Text Block] Restructuring charges Restructuring Charges Accounts payable Accounts Payable, Current Concentration Risk Type [Axis] Concentration Risk Type [Axis] Impairment loss of long-lived assets Impairment, Long-Lived Asset, Held-for-Use Equity Incentive Plans Share-based Payment Arrangement, Disclosure [Abstract] Schedule of Fair Value of Financial Assets and Liabilities Measured on a Recurring Basis Schedule of Fair Value, Assets and Liabilities Measured on Recurring Basis [Table Text Block] Foreign Foreign Tax Authority [Member] Accumulated Other Comprehensive (Loss) Income AOCI Attributable to Parent [Member] Deferred revenue - current Change In Contract With Customer Liability, Current, Rollforward [Roll Forward] Change In Contract With Customer Liability, Current, Rollforward Common stock, shares outstanding Common Stock, Shares, Outstanding Long-term investments Long-term Investments 2008 Plan Two Thousand Eight Stock Incentive Plan [Member] Two Thousand Eight Stock Incentive Plan [Member] Financial Instruments [Domain] Financial Instruments [Domain] Initial Application Period Cumulative Effect Transition [Axis] Initial Application Period Cumulative Effect Transition [Axis] Derivative [Table] Derivative [Table] Revenues: Revenues [Abstract] Deferred tax liabilities: Deferred Tax Liabilities, Net [Abstract] Maximum shares to be issued under ESPP Share-Based Compensation Arrangement By Share-Based Payment Award, Maximum Number Of Shares Under Employee Stock Purchase Plan Share-Based Compensation Arrangement By Share-Based Payment Award, Maximum Number Of Shares Under Employee Stock Purchase Plan Restructuring and Related Activities [Abstract] ASU 2014-09 Accounting Standards Update 2014-09 [Member] Document Period End Date Document Period End Date Issuance of common stock upon vesting of restricted stock units (in shares) Stock Issued During Period, Shares, Restricted Stock Award, Net of Forfeitures Initial Application Period Cumulative Effect Transition [Domain] Initial Application Period Cumulative Effect Transition [Domain] Entity Central Index Key Entity Central Index Key Concentration Risk Benchmark [Domain] Concentration Risk Benchmark [Domain] Fair value analysis, effect on fair value based on 10% change in probability of occurrence Fair Value Sensitivity Analysis, Ten Percent Change In Probability Of Occurrence, Effect On Valuation Fair Value Sensitivity Analysis, Ten Percent Change In Probability Of Occurrence, Effect On Valuation Antidilutive Securities Excluded from Computation of Earnings Per Share [Line Items] Antidilutive Securities Excluded from Computation of Earnings Per Share [Line Items] Number of Shares Share-based Compensation Arrangement by Share-based Payment Award, Options, Outstanding [Roll Forward] State taxes, net of federal benefit Effective Income Tax Rate Reconciliation, State and Local Income Taxes, Percent Schedule of Property and Equipment Property, Plant and Equipment [Table Text Block] Tax credits Deferred Tax Assets, Tax Credit Carryforwards, Research Income Statement Location [Domain] Income Statement Location [Domain] Additions (subtractions) based on tax positions related to prior year Unrecognized Tax Benefits, Decrease Resulting from Prior Period Tax Positions Debt Securities, Available-for-sale [Table] Debt Securities, Available-for-sale [Table] Supplementary disclosure of non-cash activities: Cash Flow, Noncash Investing and Financing Activities Disclosure [Abstract] Number of shares added to initial reserve Share-based Compensation Arrangement by Share-based Payment Award, Number of Additional Shares Authorized Due in one year or less Debt Securities, Available-for-Sale, Amortized Cost, Maturity, Allocated and Single Maturity Date, Year One Income Tax Disclosure [Line Items] Income Tax Disclosure [Line Items] Income Tax Disclosure [Line Items] Maximum potential payment per agreement Maximum payment per termination agreement Collaborative Arrangement, Potential Payment Per Termination Agreement, Maximum Collaborative Arrangement, Potential Payment Per Termination Agreement, Maximum Upfront license fees Collaboration And Licensing Agreements, Upfront License Fees Collaboration And Licensing Agreements, Upfront License Fees Property and equipment, net Total property and equipment, net Property, Plant and Equipment, Net Property and Equipment, Net Property, Plant and Equipment Disclosure [Text Block] Underwritten public offering Underwritten Public Offering December 2019 [Member] Underwritten Public Offering December 2019 Cash and investments Total cash equivalents and investments, Fair Value Investments and Cash Long-term investments, Cost Long-term investments, Amortized Cost Long-term investments Amortized cost of investment in debt security measured at fair value with change in fair value recognized in other comprehensive income (available-for-sale). Share-based Payment Arrangement, Expensed and Capitalized, Amount [Table] Share-based Payment Arrangement, Expensed and Capitalized, Amount [Table] Term Loans Debt Instrument [Line Items] Trading Symbol Trading Symbol Earnings Per Share [Abstract] Earnings Per Share [Abstract] Payments for loan payable, net of issuance costs Repayments of Other Long-term Debt Future obligation upon loan funding or other events Loan Agreement, Future Obligation Upon Funding Or Other Events Loan Agreement, Future Obligation Upon Funding Or Other Events Property and equipment, gross Property, Plant and Equipment, Gross Revenue Revenue from Contract with Customer Benchmark [Member] Other Deferred Tax Liabilities, Other Options vested and expected to vest (shares) Share-based Compensation Arrangement by Share-based Payment Award, Options, Vested and Expected to Vest, Outstanding, Number Inducement Plan Two Thousand Sixteen Employment Commencement Incentive Plan [Member] 2016 Employment commencement incentive plan. Contingent liabilities Loss Contingency Accrual Warrants to purchase common stock Warrant [Member] Options issued and outstanding balance, beginning (in dollars per share) Options issued and outstanding balance, ending (in dollars per share) Share-based Compensation Arrangement by Share-based Payment Award, Options, Outstanding, Weighted Average Exercise Price Accrued clinical expenses Accrued Clinical Expenses Accrued clinical expenses. Liabilities: Liabilities, Fair Value Disclosure [Abstract] Stock-based compensation Share-based Payment Arrangement, Expense Options exercisable (in years) Share-based Compensation Arrangement by Share-based Payment Award, Options, Exercisable, Weighted Average Remaining Contractual Term Research and development tax credit Research Tax Credit Carryforward [Member] Entity Current Reporting Status Entity Current Reporting Status Weighted-Average Grant Date Fair Value Per Share Share-based Compensation Arrangement by Share-based Payment Award, Equity Instruments Other than Options, Nonvested, Weighted Average Grant Date Fair Value [Abstract] Total cash equivalents and investments, Gross Unrealized Gains Cash Cash Equivalents And Investments Gross Unrealized Gains Cash, cash equivalents and investments gross unrealized gains. Shares available for grant, effect of granted (shares) Share-Based Compensation Arrangement By Share Based Payment Award, Number Of Shares Available For Grant, Decrease Due To Granted In Period Share-Based Compensation Arrangement By Share Based Payment Award, Number Of Shares Available For Grant, Decrease Due To Granted In Period Income tax provision Effective Income Tax Rate Reconciliation, Percent Loan agreement covenant, cash and cash equivalents as percentage of outstanding loan balance, minimum Loan Agreement, Covenant, Cash And Cash Equivalents As Percentage Of Outstanding Loan Balance, Minimum Loan Agreement, Covenant, Cash And Cash Equivalents As Percentage Of Outstanding Loan Balance, Minimum Amortization of (discount) premium on investment securities Accretion (Amortization) of Discounts and Premiums, Investments Amortization of deferred financing costs Amortization of Debt Issuance Costs Counterparty Name [Axis] Counterparty Name [Axis] Payables and Accruals [Abstract] Payables and Accruals [Abstract] Common stock Common Class A [Member] Long-term securities contractual maturities, minimum Available-For-Sale Securities, Debt Securities, Noncurrent, Contractual Maturities, Minimum Available-For-Sale Securities, Debt Securities, Noncurrent, Contractual Maturities, Minimum Unbilled revenue Contract with Customer, Asset, after Allowance for Credit Loss, Current Cash and cash equivalents at beginning of period Cash and cash equivalents at end of period Cash, Cash Equivalents, Restricted Cash and Restricted Cash Equivalents Term Loan B Term Loan 2022 B [Member] Term Loan 2022 B Tax Credit Carryforward, Name [Domain] Tax Credit Carryforward, Name [Domain] United States UNITED STATES Common stock, par value (in dollars per share) Common Stock, Par or Stated Value Per Share Allowance for credit loss on available-for-sale debt securities Debt Securities, Available-for-sale, Allowance for Credit Loss Schedule of Collaboration Partnerships Schedules of Concentration of Risk, by Risk Factor [Table Text Block] Current assets: Assets, Current [Abstract] Prior to first anniversary of closing date Debt Instrument, Redemption, Period One [Member] Common stock reserved for future issuance (in shares) Common Stock, Capital Shares Reserved for Future Issuance Leases [Abstract] Leases [Abstract] Income Taxes Income Tax, Policy [Policy Text Block] LIBOR London Interbank Offered Rate (LIBOR) [Member] Impairment of Long-Lived Assets Impairment or Disposal of Long-Lived Assets, Policy [Policy Text Block] Entity Address, Postal Zip Code Entity Address, Postal Zip Code Revenue Recognition Revenue from Contract with Customer [Policy Text Block] Issuance of common stock upon exercise of options (in shares) Options exercised (shares) Share-based Compensation Arrangement by Share-based Payment Award, Options, Exercises in Period Schedule of Cost of Revenue Recognized and Paid Cost of Revenue [Table Text Block] The tabular disclosure of cost of revenue recognized and amount of cost paid. 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