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Sunovion Pharmaceuticals, Inc. 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milestone payments received License Agreement, Regulatory Milestones, Payments Received License Agreement, Regulatory Milestones, Payments Received Revenue from Contract with Customer [Abstract] Net change in cash, cash equivalents and restricted cash Cash, Cash Equivalents, Restricted Cash, and Restricted Cash Equivalents, Period Increase (Decrease), Including Exchange Rate Effect Commercial paper Commercial Paper [Member] Entity Central Index Key Entity Central Index Key Antidilutive Securities, Name [Domain] Antidilutive Securities, Name [Domain] Interest income Investment Income, Interest Measurement Frequency [Axis] Measurement Frequency [Axis] Schedule of Share-based Compensation Arrangements by Share-based Payment Award [Table] Schedule of Share-Based Compensation Arrangements by Share-Based Payment Award [Table] Accrued other expenses Other Accrued Liabilities, Current Majority Shareholder Majority Shareholder [Member] Entity [Domain] Entity [Domain] City Area Code City Area Code Accrued professional fees Accrued Professional Fees, Current Assets Assets [Abstract] MSG MSG [Member] MSG Long-term Debt, Type [Domain] Long-Term Debt, Type [Domain] Amortization of regulatory milestones Amortization of Regulatory Milestone [Member] Amortization of Regulatory Milestone Schedule of Share-based Compensation Schedule of Share-based Compensation Arrangement, Allocation of Recognized Period Costs [Table Text Block] Schedule of Share-based Compensation Arrangement, Allocation of Recognized Period Costs [Table Text Block] Statement of Stockholders' Equity [Abstract] Statement of Stockholders' Equity [Abstract] Additions Deferred Revenue, Additions1 Deferred Revenue, Additions1 Termination notice period Related Party Transaction, Termination Notice Period Related Party Transaction, Termination Notice Period Cash flows from financing activities: Net Cash Provided by (Used in) Financing Activities [Abstract] Amounts due to related parties Due to Related Parties, Current Number of independent directors required for audit committee Related Party Transaction, Number of Independent Directors Required for Audit Committee Related Party Transaction, Number of Independent Directors Required for Audit Committee Asset Class [Axis] Asset Class [Axis] Net Loss per Common Share Earnings Per Share, Policy [Policy Text Block] Supplemental Disclosures of Non-Cash Financing and Investing Information: Cash Flow, Noncash Investing and Financing Activities Disclosure [Abstract] Share-based compensation Share-Based Payment Arrangement, Noncash Expense Variable Rate [Axis] Variable Rate [Axis] Other liabilities Other Liabilities, Noncurrent Other liabilities Increase (Decrease) in Other Operating Liabilities Purchases of property and equipment Payments to Acquire Property, Plant, and Equipment R&D expense Research and Development Expense [Member] Disaggregation of Revenue [Line Items] Disaggregation of Revenue [Line Items] Proceeds received from license agreement milestone Additions Proceeds from Collaborators Right-of-use asset obtained in exchange for operating lease obligation Right-of-Use Asset Obtained in Exchange for Operating Lease Liability Cost of product revenue Cost of Sales [Member]