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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 Liabilities and stockholders’ equity Liabilities and Equity [Abstract] Non-cash interest expense Amortization of Debt Discount (Premium) Cash and Cash Equivalents [Domain] Cash and Cash Equivalents [Domain] Remaining funding based on milestone achievement Remaining Funding Based On Conditional Milestone Achievement Remaining Funding Based On Conditional Milestone Achievement Debt Instrument, Redemption, Period [Axis] Debt Instrument, Redemption, Period [Axis] Stockholders’ equity: Equity, Attributable to Parent [Abstract] Potential commercialization milestones Collaborative Arrangement, Potential Commercialization Milestones Collaborative Arrangement, Potential Commercialization Milestones Concentration Risk Benchmark [Domain] Concentration Risk Benchmark [Domain] Gross Unrealized Losses Debt Securities, Available-for-Sale, Accumulated Gross Unrealized Loss, before Tax Non-cash royalty revenue Revenue to be received Contract with Customer, Liability Issuance of common stock upon exercise of options (in shares) Options exercised (in shares) Share-Based Compensation Arrangement by Share-Based Payment Award, Options, Exercises in Period Inventory Inventory Inventory, Gross Schedule of Computation of Net Loss Per Common Share Schedule of Earnings Per Share, Basic and Diluted [Table Text Block] Total cost of goods sold Cost of Goods and Services Sold Schedule of Noncurrent Inventory Schedule of Inventory, Noncurrent [Table Text Block] Executive Category: Executive Category [Axis] Number of RSUs Share-Based Compensation Arrangement by Share-Based Payment Award, Equity Instruments Other than Options, Nonvested, Number of Shares [Roll Forward] Options exercised (in dollars per share) Share-Based Compensation Arrangements by Share-Based Payment Award, Options, Exercises in Period, Weighted Average Exercise Price Level 1 Fair Value, Inputs, Level 1 [Member] Name Measure Name Name Forgone Recovery, Individual Name Loan agreement, covenant, cash and cash equivalents as percentage of outstanding loan balance, calculation period (in months) Loan Agreement, Covenant, Cash And Cash Equivalents As Percentage Of Outstanding Loan Balance, Calculation Period Loan Agreement, Covenant, Cash And Cash Equivalents As Percentage Of Outstanding Loan Balance, Calculation Period Purchases of investments Payments to Acquire Short-Term Investments Equity Components [Axis] Equity Components [Axis] Financial Instruments [Domain] Financial Instruments [Domain] Additional 402(v) Disclosure Additional 402(v) Disclosure [Text Block] Accrued and other liabilities Increase (Decrease) in Accrued Liabilities Options granted (in shares) Share-Based Compensation Arrangement by Share-Based Payment Award, Options, Grants in Period, Gross Underlying Securities Award Underlying Securities Amount Entity Small Business Entity Small Business Closing fee Debt Instrument, Closing Fee Amount Debt Instrument, Closing Fee Amount Local Phone Number Local Phone Number Total cash equivalents and investments, Gross Unrealized Losses Cash Cash Equivalents And Investments Gross Unrealized Losses Cash, cash equivalents and investments gross unrealized losses. Accounts receivable Increase (Decrease) in Accounts Receivable Recovery of Erroneously Awarded Compensation Disclosure [Line Items] Selling, general and administrative Selling, General and Administrative Expenses [Member] Percentage of royalty revenue Percentage of Royalty Revenue Represents percentage of royalty revenue. 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Interest expense Interest Expense AmerisourceBergen Drug Corporation AmerisourceBergen Drug Corporation [Member] AmerisourceBergen Drug Corporation Potential development and commercialization milestones Collaborative Arrangement, Potential Development And Commercialization Milestones Represents the amount of future development and commercialization milestone under collaborative arrangements. Fair Value Hierarchy and NAV [Domain] Fair Value Hierarchy and NAV [Domain] Stockholders' Equity Note [Abstract] Stockholders' Equity Note [Abstract] Trading Arrangement: Trading Arrangement [Axis] Imputed interest expenses Lessee, Operating Lease, Liability, Undiscounted Excess Amount Use of Estimates Use of Estimates, Policy [Policy Text Block] PEO Actually Paid Compensation Amount PEO Actually Paid Compensation Amount Long-term Debt, Type [Domain] Long-Term Debt, Type [Domain] Entity File Number Entity File Number Loss Contingencies [Table] Loss Contingencies [Table] Schedule of Antidilutive Securities Excluded from Computation of Earnings Per Share [Table] Schedule of Antidilutive Securities Excluded from Computation of Earnings Per Share [Table] Current portion of operating lease liability Current portion of lease liabilities Less: Current portion of operating lease liability Operating Lease, Liability, Current Licensing revenue License License [Member] Allowance for credit loss on available for-sale debt securities Debt Securities, Available-for-Sale, Allowance for Credit Loss Issuance of common stock under employee stock purchase plan (in shares) Stock Issued During Period, Shares, Employee Stock Purchase Plans Fair Value, Liabilities Measured on Recurring Basis, Unobservable Input Reconciliation [Line Items] Fair Value, Liabilities Measured on Recurring Basis, Unobservable Input Reconciliation [Line Items] Gross To Net Sales Accrual And Reserve Classification [Domain] Gross To Net Sales Accrual And Reserve Classification [Domain] Gross To Net Sales Accrual And Reserve Classification [Domain] Proceeds from maturities and redemptions of investments Proceeds from Sale and Maturity of Debt Securities, Available-for-Sale Entity Shell Company Entity Shell Company Recent Accounting Pronouncements New Accounting Pronouncements, Policy [Policy Text Block] Restatement Determination Date Restatement Determination Date Secured Overnight Financing Rate (SOFR) Secured 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[Member] Derivative Liabilities Derivative Instruments and Hedging Activities Disclosure [Text Block] Common stock Common Class A [Member] Average Remaining Vesting Period (Years) Share-Based Payment Arrangement, Nonvested Award, Cost Not yet Recognized, Period for Recognition Total operating expenses Costs and Expenses Comprehensive loss Comprehensive Income (Loss), Net of Tax, Attributable to Parent Unrecognized Compensation Expense Share-Based Payment Arrangement, Nonvested Award, Cost Not yet Recognized, Amount Document Type Document Type Long-term debt, net of current portion Loans Payable, Noncurrent Tabular List, Table Tabular List [Table Text Block] Entity Address, Address Line One Entity Address, Address Line One Prepaid commercial manufacturing Prepaid Commercial Manufacturing, Current Prepaid Commercial Manufacturing, Current Entity Address, Address Line Two Entity Address, Address Line Two Accrued expenses and other current liabilities Accrued Liabilities and Other Liabilities Equity Incentive Plans Share-Based Payment Arrangement [Text Block] Basis of Presentation Basis of Accounting, Policy [Policy Text Block] Other, net Other Noncash Income (Expense) Weighted-Average Exercise Price per Share Share-Based Compensation Arrangement by Share-Based Payment Award, Options, Outstanding, Weighted Average Exercise Price [Abstract] Fair Value, Liabilities Measured on Recurring Basis, Unobservable Input Reconciliation [Table] Fair Value, Liabilities Measured on Recurring Basis, Unobservable Input Reconciliation [Table] Derivative [Table] Derivative [Table] Customer Customer Concentration Risk [Member] Variable Rate [Axis] Variable Rate [Axis] Cash Cash [Member] Income Statement [Abstract] Income Statement [Abstract] Prepayment premium (as percent) Debt Instrument, Prepayment Fee, Percentage The percentage of fee payable on prepayment of debt. Issuance of common stock in at the market offering (in shares) Stock Issued During Period, Shares, New Issues Options forfeited or canceled (in shares) Share-Based Compensation Arrangement by Share-Based Payment Award, Options, Forfeitures in Period Title of 12(b) Security Title of 12(b) Security Short-term securities, contractual maturities maximum (in years) Available-For-Sale Securities, Debt Securities, Current, Contractual Maturities, Maximum Available-For-Sale Securities, Debt Securities, Current, Contractual Maturities, Maximum Amounts invoiced as prepayments for product supply Contract With Customer, Liability, Revenue Invoiced As Prepayments For Product Supply, Noncurrent Contract With Customer, Liability, Revenue Invoiced As Prepayments For Product Supply, Noncurrent U.S. treasury securities US Treasury Notes Securities [Member] Insider Trading Policies and Procedures Adopted Insider Trading Policies and Procedures Adopted [Flag] Short-term investments: Debt Securities, Available-for-Sale, Fair Value to Amortized Cost, after Allowance for Credit Loss [Abstract] 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. Aggregate Erroneous Compensation Not Yet Determined Aggregate Erroneous Compensation Not Yet Determined [Text Block] Numerator: Net Income (Loss) Attributable to Parent [Abstract] Outstanding balance, beginning (in dollars per share) Outstanding 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 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] Forgone Recovery due to Expense of Enforcement, Amount Forgone Recovery due to Expense of Enforcement, Amount Share-based Payment Arrangement [Abstract] Share-Based Payment Arrangement [Abstract] Entity Tax Identification Number Entity Tax Identification Number 2023 Open Market Sales Agreement Open Market Sales Agreement 2023, At The Market Offering [Member] Open Market Sales Agreement 2023, At The Market Offering Exit fee, term (in years) Loan Agreement, Exit Fee, Term Loan Agreement, Exit Fee, Term Additional details Lessee, Operating Lease, Description [Abstract] Total Inventory, Net Inventory, non-current Inventory, non-current Inventory, Noncurrent Financial Instrument [Axis] Financial Instrument [Axis] Entity Interactive Data Current Entity Interactive Data Current Disaggregation of Revenue [Table] Disaggregation of Revenue [Table] Fosun Pharma Shanghai Fosun Pharmaceutical Industrial Development [Member] Represents Shanghai Fosun Pharmaceutical Industrial Development. Debt Securities, Available-for-sale [Table] Debt Securities, Available-for-Sale [Table] Reclassify amounts to be recognized in the next twelve months Contract With Customer, Liability, Revenue To Be Recognized In Next Twelve Months Contract With Customer, Liability, Revenue To Be Recognized In Next Twelve Months Total Shareholder Return Amount Total Shareholder Return Amount Product sales, net Product [Member] Entity Common Stock, Shares Outstanding Entity Common Stock, Shares Outstanding Adjustment To PEO Compensation, Footnote Adjustment To PEO Compensation, Footnote [Text Block] Knight Agreement License Agreement Development Commercialization Distribution In Canada [Member] Agreement for the development, commercialization and distribution fo tenapanor in Canada. The Knight Agreement. Inventory Disclosure [Abstract] Share-based Compensation Arrangement by Share-based Payment Award [Line Items] Share-Based Compensation Arrangement by Share-Based Payment Award [Line Items] Fair Value Hierarchy and NAV [Axis] Fair Value Hierarchy and NAV [Axis] Additional uncommitted capital Line Of Credit Facility, Accordion Feature, Additional Uncommitted Capital Line Of Credit Facility, Accordion Feature, Additional Uncommitted Capital Accumulated deficit Accumulated deficit Retained Earnings (Accumulated Deficit) Measure: Measure [Axis] Commitments and Contingencies Disclosure [Abstract] Commitments and Contingencies Disclosure [Abstract] Name Outstanding Recovery, Individual Name Term loan face amount Debt Instrument, Face Amount Entity Incorporation, State or Country Code Entity Incorporation, State or Country Code Current assets: Assets, Current [Abstract] Leases [Abstract] Leases [Abstract] Entity Address, State or Province Entity Address, State or Province Compensation Actually Paid vs. Total Shareholder Return Compensation Actually Paid vs. Total Shareholder Return [Text Block] Counterparty Name [Axis] Counterparty Name [Axis] ESPP ESPP shares issuable Employee Stock Purchase Plan [Member] Employee Stock Purchase Plan [Member] Operating activities Net Cash Provided by (Used in) Operating Activities [Abstract] Antidilutive Securities Excluded from Computation of Earnings Per Share [Line Items] Antidilutive Securities Excluded from Computation of Earnings Per Share [Line Items] Cash paid for operating lease Operating Lease, Payments Common stock, shares outstanding (in shares) Common Stock, Shares, Outstanding Weighted-average sales price per share (in dollars per share) Sale Of Stock, Weighted-Average Price Per Share Sale Of Stock, Weighted-Average Price Per Share PEO PEO [Member] Aggregate cost of revenue recognized Cost Of Revenue, Aggregate Amount Recognized Cost of revenue, aggregate amount recognized. AZ Termination Agreement AstraZeneca Termination Agreement [Member] AstraZeneca Termination Agreement Beginning balance (in shares) Ending balance (in shares) Shares, Outstanding Upfront payment received Proceeds from License Fees Received Asset Class [Domain] Asset Class [Domain] Common stock, par value (in dollars per share) Common Stock, Par or Stated Value Per Share Sale of Stock [Axis] Sale of Stock [Axis] Class of Stock [Domain] Class of Stock [Domain] Net cash used in investing activities Net Cash Provided by (Used in) Investing Activities Customer [Domain] Customer [Domain] Schedule of Current Inventory Schedule of Inventory, Current [Table Text Block] Number of Shares Share-Based Compensation Arrangement by Share-Based Payment Award, Options, Outstanding [Roll Forward] Debt Instrument [Axis] Debt Instrument [Axis] Outstanding Aggregate Erroneous Compensation Amount Outstanding Aggregate Erroneous Compensation Amount Total operating lease liabilities Operating Lease, Liability Schedule of Future Debt Payment Obligations Schedule of Maturities of Long-Term Debt [Table Text Block] Total liabilities Liabilities Percentage of non-royalty revenue Percentage Of Non-Royalty Revenue Represents percentage of non-royalty revenue. Total Shareholder Return Vs Peer Group Total Shareholder Return Vs Peer Group [Text Block] Stock-based Compensation [Line Items] Share-Based Payment Arrangement, Expensed and Capitalized, Amount [Line Items] Prepaid expenses and other assets Increase (Decrease) in Prepaid Expense and Other Assets Accumulated Other Comprehensive Income AOCI Attributable to Parent [Member] Aggregate Erroneous Compensation Amount Aggregate Erroneous Compensation Amount Measurement Frequency [Domain] Measurement Frequency [Domain] All Executive Categories All Executive Categories [Member] Deferred revenue, non-current Beginning balance Ending balance Contract with Customer, Liability, Noncurrent Title of Individual [Axis] Title of Individual [Axis] Non-Rule 10b5-1 Arrangement Adopted Non-Rule 10b5-1 Arrangement Adopted [Flag] Plan Name [Axis] Plan Name [Axis] Debt Disclosure [Abstract] Debt Disclosure [Abstract] Right-of-use assets and lease liabilities Assets and Liabilities, Lessee [Abstract] Product supply revenue Product Supply Revenue [Member] Product Supply Revenue Earnings Per Share [Abstract] Earnings Per Share [Abstract] Exit fee (as percent) Exit Fee, Percentage Exit Fee, Percentage Common stock, $0.0001 par value; 500,000,000 shares authorized; 233,959,744 and 232,453,190 shares issued and outstanding as of March 31, 2024 and December 31, 2023, respectively. Common Stock, Value, Issued Total of gross proceeds Equity Sales Agreement, Proceeds From Shares Issued Since Inception Equity Sales Agreement, Proceeds From Shares Issued Since Inception Organization, Consolidation and Presentation of Financial Statements [Abstract] Organization, Consolidation and Presentation of Financial Statements [Abstract] Non-cash lease expense Operating Lease, Right-of-Use Asset, Periodic Reduction Commission on sale of stock per agreement (as percent) Stock Issuance Cost, Commission, Percent Stock Issuance Cost, Commission, Percent Awards Close in Time to MNPI Disclosures, Table Awards Close in Time to MNPI Disclosures [Table Text Block] Total current assets Assets, Current Schedule of Revenue from Customers as a Percentage of Total Product Revenue, Net Schedules of Concentration of Risk, by Risk Factor [Table Text Block] Revenue from Contract with Customer [Abstract] All Individuals All Individuals [Member] Supplementary disclosure of cash flow information: Supplemental Cash Flow Information [Abstract] Litigation Case [Domain] Litigation Case [Domain] Entity Filer Category Entity Filer Category Proceeds from 2022 Loan, net of issuance costs Proceeds from Issuance of Secured Debt Non-PEO NEO Average Total Compensation Amount Non-PEO NEO Average Total Compensation Amount Final fee due upon maturity, acceleration, prepayment, or termination (as percent) Debt Instrument, Fee Due Upon Maturity, Acceleration, Prepayment, Termination, Percentage Debt Instrument, Fee Due Upon Maturity, Acceleration, Prepayment, Termination, Percentage Statement [Table] Statement [Table] AstraZeneca Astrazeneca [Member] Represents information pertaining to AstraZeneca. Current Fiscal Year End Date Current Fiscal Year End Date 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 Proceeds from milestone payments Revenue, Remaining Performance Obligation, Variable Consideration Amount Revenue, Remaining Performance Obligation, Variable Consideration Amount Number of payment tranches for fee receivable for reduction in royalty rate Collaborative Arrangement, Fee Receivable For Reduction In Royalty Rate, Number Of Payment Tranches Collaborative Arrangement, Fee Receivable For Reduction In Royalty Rate, Number Of Payment Tranches PEO Name PEO Name Concentration risk (as percent) Concentration Risk, Percentage Estimated fair value Beginning balance Ending balance Fair Value, Measurement with Unobservable Inputs Reconciliation, Recurring Basis, Liability Value Preferred stock, shares authorized (in shares) Preferred Stock, Shares Authorized Granted (in dollars per share) Share-Based Compensation Arrangement by Share-Based Payment Award, Equity Instruments Other than Options, Grants in Period, Weighted Average Grant Date Fair Value Preferred stock, shares outstanding (in shares) Preferred Stock, Shares Outstanding Asset-backed securities Asset-backed securities Asset-Backed Securities [Member] Net cash used in operating activities Net Cash Provided by (Used in) Operating Activities Additional committed capital Line Of Credit Facility, Accordion Feature, Additional Committed Capital Line Of Credit Facility, Accordion Feature, Additional Committed Capital Class of Stock [Axis] Class of Stock [Axis] 2018 Term Loan Term Loan 2018 [Member] Term Loan 2018 Erroneously Awarded Compensation Recovery Erroneously Awarded Compensation Recovery [Table] Short-term investments Debt Securities, Available-for-Sale, Current Less: Unaccreted value of final fee Debt Instrument, Fee Amount After second anniversary to maturity date Debt Instrument, Redemption, Period Three [Member] Fosun Agreement License Agreement Development Commercialization Distribution In China [Member] Agreement for the development, commercialization and distribution of tenapanor in China. The Fosun Agreement. 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The 2017 KKC Agreement. 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