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sales Cost of Product and Service Sold Sagard Healthcare Partners Sagard Healthcare Partners [Member] Sagard Healthcare Partners Basic and Diluted Loss Per Common Share Computation Schedule of Earnings Per Share, Basic and Diluted [Table Text Block] Shares, Exercisable (in shares) Share-Based Compensation Arrangement by Share-Based Payment Award, Options, Exercisable, Number Subsequent Events [Abstract] Segment Reporting [Abstract] Pay vs Performance Disclosure, Table Pay vs Performance [Table Text Block] MGC028 MGC028 [Member] MGC028 Forgone Recovery due to Violation of Home Country Law, Amount Forgone Recovery due to Violation of Home Country Law, Amount Risk-free interest rate Share-Based Compensation Arrangement by Share-Based Payment Award, Fair Value Assumptions, Risk Free Interest Rate Entity Tax Identification Number Entity Tax Identification Number Costs and expenses: Costs and Expenses [Abstract] Milestone Type [Domain] Milestone Type [Domain] Milestone Type [Domain] Weighted-average exercise price of stock options outstanding (in dollars per share) Weighted- Average Exercise Price, Outstanding, Beginning Balance (in dollars per share) Weighted- Average Exercise Price, Outstanding, Ending Balance (in dollars per share) Share-Based Compensation Arrangement by Share-Based Payment Award, Options, Outstanding, Weighted Average Exercise Price Forgone Recovery due to Expense of Enforcement, Amount Forgone Recovery due to Expense of Enforcement, Amount Revenues From License Agreements RevenuesFromLicenseAgreementsMember Share-based Compensation Arrangement by Share-based Payment Award [Line Items] Share-Based Compensation Arrangement by Share-Based Payment Award [Line Items] Common stock, par value (in dollars per share) Common Stock, Par or Stated Value Per Share MGC030 MGC030 [Member] MGC030 Number of performance obligations Number Of Performance Obligations Potential option fees Opt-In Fee Opt-In Fee Variable consideration recognized Revenue, Multiple-Deliverable Arrangements, Determination Of Selling Price, Amount Revenue, Multiple-Deliverable Arrangements, Determination Of Selling Price, Amount Number of proprietary product candidates advancing in clinical development Number Of Proprietary Product Candidates Advancing In Clinical Development Number Of Proprietary Product Candidates Advancing In Clinical Development Non-cash interest expense recognized Interest Expense, Nonoperating Trading Arrangement: Trading Arrangement [Axis] Total Shareholder Return Amount Total Shareholder Return Amount Financial Assets Measured at Fair Value on a Recurring Basis Fair Value Measurements, Recurring and Nonrecurring [Table Text Block] Subsequent Event Subsequent Events [Text Block] Insider Trading Arrangements [Line Items] Security Exchange Name Security Exchange Name Weighted- Average Exercise Price, Forfeited (in dollars per share) Share-Based Compensation Arrangements by Share-Based Payment Award, Options, Forfeitures in Period, Weighted Average Exercise Price Total liabilities Liabilities Property and equipment included in accounts payable or accruals Capital Expenditures Incurred but Not yet Paid Pension Adjustments Prior Service Cost Pension Adjustments Prior Service Cost [Member] MGC026 MGC026 [Member] MGC026 Proceeds from sale and maturities of marketable securities Proceeds from Sale and Maturity of Debt Securities, Available-for-Sale Non-cash royalty revenue payable to Sagard Noncash Royalty Revenue Payable Noncash Royalty Revenue Payable Material Terms of Trading Arrangement Material Terms of Trading Arrangement [Text Block] Asset Class [Domain] Asset Class [Domain] Stock plan related activity Shares Granted, Value, Share-Based Payment Arrangement, after Forfeiture Statement [Line Items] Statement [Line Items] Rule 10b5-1 Arrangement Adopted Rule 10b5-1 Arrangement Adopted [Flag] Cash and cash equivalents Cash and Cash Equivalent Counterparty Name [Axis] Counterparty Name [Axis] Subsequent Event [Line Items] Subsequent Event [Line Items] Common Stock Common Stock [Member] Share-Based Compensation Arrangement by Share-Based Payment Award, Non-Option Equity Instruments, Exercised Share-Based Compensation Arrangement by Share-Based Payment Award, Equity Instruments Other than Options, Vested in Period Securities Fair Value Debt Securities, Available-for-Sale Entity Incorporation, State or Country Code Entity Incorporation, State or Country Code Non-NEOs Non-NEOs [Member] Corporate debt securities Corporate Debt Securities [Member] Effective interest rate Royalty Monetization Arrangement, Interest Rate, Effective Percentage Royalty Monetization Arrangement, Interest Rate, Effective Percentage Net change in cash and cash equivalents Cash, Cash Equivalent, Restricted Cash, and Restricted Cash Equivalent, Period Increase (Decrease), Including Exchange Rate Effect and Discontinued Operation Potential target nomination, option fees and milestone payments Potential target nomination, option fees and milestone payments Potential target, nomination, option fees and milestone payments Research and Development Arrangement, Contract to Perform for Others, Type [Domain] Research and Development Arrangement, Contract to Perform for Others, Type [Domain]