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Schedule Of Share Based Compensation Arrangements By Share Based Payment Award [Table] Schedule of Share-Based Compensation Arrangements by Share-Based Payment Award [Table] Stock Options, Beginning Balance Stock Options, Ending Balance Share-Based Compensation Arrangement by Share-Based Payment Award, Options, Outstanding, Number Document Fiscal Year Focus Document Fiscal Year Focus Unrecognized Tax Benefits, Income Tax Penalties and Interest Accrued, Total Unrecognized tax benefits, tax penalties and interest accrued Unrecognized Tax Benefits, Income Tax Penalties and Interest Accrued Schedule of Carrying Amount and Approximate Fair Value of Financial Instruments Fair Value Measurements, Recurring and Nonrecurring [Table Text Block] 2024 Lessee, Operating Lease, Liability, to be Paid, Year Two Basic net loss per common share Earnings Per Share, Basic Earnings Per Share, Basic, Total Assets: Assets [Abstract] Prepaid expenses and other current assets Prepaid Expense and Other Assets, Current Development Milestone Development Milestone [Member] Development milestone. 2004 Plan and 2013 Plan Share-Based Payment Arrangement [Member] Lease commenced date Lease Commenced Date Lease commenced date. Financial Instrument Financial Instrument [Axis] Long-Lived Tangible Asset Long-Lived Tangible Asset [Axis] Number of Option Shares Share-Based Compensation Arrangement by Share-Based Payment Award, Options, Outstanding [Roll Forward] Liabilities and Stockholders’ Equity Liabilities and Equity [Abstract] Income Tax Authority Income Tax Authority [Axis] Net Income (Loss), Including Portion Attributable to Noncontrolling Interest, Total Net loss Net Income (Loss), Including Portion Attributable to Noncontrolling Interest Permanent differences Effective Income Tax Rate Reconciliation Permanent Differences Effective Income Tax Rate Reconciliation, Permanent Differences Current assets: Assets, Current [Abstract] Prepaid expenses Prepaid Expense Components of Deferred Income Taxes Schedule of Deferred Tax Assets and Liabilities [Table Text Block] Fair Value Hierarchy and NAV Fair Value Hierarchy and NAV [Domain] Additions for tax positions taken in the prior year Unrecognized Tax Benefits, Increase Resulting from Prior Period Tax Positions Discretionary contributions to employee savings plan Defined Contribution Plan, Employer Discretionary Contribution Amount Payables and Accruals [Abstract] Measurement Frequency [Domain] Changes in assets and liabilities: Increase (Decrease) in Operating Capital [Abstract] United States Income (Loss) from Continuing Operations before Income Taxes, Domestic Cover [Abstract] 2027 Lessee, Operating Lease, Liability, to be Paid, Year Five Number of vested shares Share-Based Compensation Arrangement by Share-Based Payment Award, Equity Instruments Other than Options, Vested in Period Research and experimentation capitalization Deferred Tax Assets Research and Experimentation Capitalization Deferred tax assets research and experimentation capitalization. Current liabilities: Liabilities, Current [Abstract] Maximum Maximum [Member] Summary of Stock-based Compensation Expense Share-Based Payment Arrangement, Expensed and Capitalized, Amount [Table Text Block] Net cash used in investing activities Net Cash Provided by (Used in) Investing Activities Stock Options, Exercised Issuance of common stock for option exercises, shares Share-Based Compensation Arrangement by Share-Based Payment Award, Options, Exercises in Period Use of Estimates Use of Estimates, Policy [Policy Text Block] ATM Agreement At-the-market issuance sales agreement At Market Issuance Sales Agreement [Member] At market issuance sales agreement. Deferred Tax Liabilities, Gross, Total Total deferred tax liabilities Deferred Tax Liabilities, Gross Issuance of common stock for option exercises Stock Issued During Period, Value, Stock Options Exercised Segment Reporting Segment Reporting, Policy [Policy Text Block] Property and equipment, useful lives Property, Plant and Equipment, Useful Life Effective Income Tax Rate Reconciliation, Tax Credit, Percent, Total Tax credits Effective Income Tax Rate Reconciliation, Tax Credit, Percent Deferred tax assets: Deferred Tax Assets, Net [Abstract] Common stock, shares authorized Common Stock, Shares Authorized Trading Symbol Trading Symbol Common Stock Reserved for Future Issuance Schedule of Stockholders Equity [Table Text Block] Subsequent Event Type Subsequent Event Type [Axis] Other, net Deferred Tax Assets, Other Genzyme Corporation Genzyme Corporation [Member] Genzyme corporation. Performance Options Performance Shares [Member] Expiration of attributes Effective Income Tax Rate Reconciliation Expiration Of Attribute Effective income tax rate reconciliation expiration of attribute. Comprehensive loss Comprehensive Income (Loss), Net of Tax, Attributable to Parent Risk-free interest rate Share-Based Compensation Arrangement by Share-Based Payment Award, Fair Value Assumptions, Risk Free Interest Rate Accounts Payable, Current, Total Accounts payable Accounts Payable, Current Plan Name Plan Name [Axis] Long-Lived Tangible Asset Long-Lived Tangible Asset [Domain] Common stock, par value Common Stock, Par or Stated Value Per Share Entity Well-known Seasoned Issuer Entity Well-known Seasoned Issuer Kissei Pharmaceutical Co., Ltd Kissei Pharmaceutical Co Ltd [Member] Kissei Pharmaceutical Co., Ltd. Weighted Average Exercise Price, Granted Share-Based Compensation Arrangements by Share-Based Payment Award, Options, Grants in Period, Weighted Average Exercise Price Increase in number of shares of common stock reserved for issuance Share-Based Compensation Arrangement by Share-Based Payment Award, Number of Additional Shares Authorized Unusual Risk or Uncertainty, Nature Unusual Risk or Uncertainty, Nature [Domain] Potentially dilutive outstanding securities excluded from diluted net loss per common share Antidilutive Securities Excluded from Computation of Earnings Per Share, Amount Fair Value Cash equivalents, fair value Cash and Cash Equivalents, Fair Value Disclosure Net operating loss carried forward indefinitely, percentage of taxable income Net Operating Loss Carryforwards Indefinitely Percentage Of Taxable Income Net operating loss carryforwards indefinitely percentage of taxable income.