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Summary of Significant Accounting Policies (Details Textual) | 1 Months Ended | 12 Months Ended |
--- | --- | --- | ---
Jan. 31, 2016 shares | Jan. 31, 2010 USD ($) right | Dec. 31, 2015 USD ($) segment shares | Dec. 31, 2014 USD ($) segment shares | Dec. 31, 2013 USD ($) shares | Aug. 31, 2014 USD ($)
Basis of Presentation [Line Items] |  |  |  |  |  |
Common shares excluded from computation | shares |  |  | 3,300,000 | 5,100,000 | 800,000 |
Maturity period of cash and cash equivalents, maximum |  |  | 3 months |  |  |
Reserve for obsolete inventory |  |  | $ 0 | $ 0 |  |
Accounts receivable outstanding considered past due after period, minimum |  |  | 30 days |  |  |
Accounts receivable outstanding considered past due after period, maximum |  |  | 90 days |  |  |
Allowance for doubtful accounts |  |  | $ 0 | 0 |  |
Definite lived intangibles, useful life |  |  | 20 years |  |  |
Amortization expense |  |  | $ 2,400,000 | 2,400,000 | $ 2,400,000 |
Estimated amortization expense [Abstract] |  |  |  |  |  |
Amortization expense, 2016 |  |  | 2,400,000 |  |  |
Amortization expense, 2017 |  |  | 2,400,000 |  |  |
Amortization expense, 2018 |  |  | 2,400,000 |  |  |
Amortization expense, 2019 |  |  | 2,400,000 |  |  |
Amortization expense, 2020 |  |  | 2,400,000 |  |  |
Amortization expense, 2021 |  |  | 2,400,000 |  |  |
Depreciation expense |  |  | $ 200,000 | $ 300,000 | 300,000 |
Restocking fee (percent) |  |  | 20.00% |  |  |
Milestone payment received |  |  | $ 0 |  |  |
Share-based Compensation [Abstract] |  |  |  |  |  |
Number of reportable segments | segment |  |  | 1 | 2 |  |
Payments to CVR holders |  |  | $ 6,740,000 | $ 3,493,000 | 989,000 |
Other current liabilities |  |  | 8,000 | 1,063,000 |  |
Long-term deferred income taxes |  |  |  | 2,792,000 |  |
Impairment of Intangible Assets, Finite-lived |  |  | $ 0 | 0 | 0 |
Stock Options | 2002 Stock Incentive Plan |  |  |  |  |  |
Share-based Compensation [Abstract] |  |  |  |  |  |
Award expiration period |  |  | 10 years |  |  |
Stock Options | Vest 1/8 on the six month anniversary of the date of grant | 2002 Stock Incentive Plan |  |  |  |  |  |
Share-based Compensation [Abstract] |  |  |  |  |  |
Award vesting period |  |  | 6 months |  |  |
Award vesting right percentage |  |  | 12.50% |  |  |
Stock Options | Vest 1/48 each month for forty-two months | 2002 Stock Incentive Plan |  |  |  |  |  |
Share-based Compensation [Abstract] |  |  |  |  |  |
Award vesting period |  |  | 42 months |  |  |
Award vesting right percentage |  |  | 2.08% |  |  |
Director | 2002 Stock Incentive Plan |  |  |  |  |  |
Share-based Compensation [Abstract] |  |  |  |  |  |
Award vesting period |  |  | 1 year |  |  |
Minimum |  |  |  |  |  |
Estimated amortization expense [Abstract] |  |  |  |  |  |
Sales/revenues from partners reporting period |  |  | 30 days |  |  |
Maximum |  |  |  |  |  |
Estimated amortization expense [Abstract] |  |  |  |  |  |
Sales/revenues from partners reporting period |  |  | 60 days |  |  |
CyDex |  |  |  |  |  |
Estimated amortization expense [Abstract] |  |  |  |  |  |
Fair value of contingent liability |  |  | $ 9,500,000 | 11,500,000 |  |
Contingent liability change in amount |  |  | 3,800,000 | 5,700,000 | (600,000) |
Contingent liability, cash payment |  |  | 5,800,000 | 3,500,000 | 1,000,000 |
Metabasis Therapeutics |  |  |  |  |  |
Estimated amortization expense [Abstract] |  |  |  |  |  |
Fair value of contingent liability |  | $ 9,100,000 | 4,000,000 | 3,700,000 |  |
Contingent liability change in amount |  |  | 1,200,000 | (500,000) | 4,200,000 |
Number of contingent value rights | right |  | 4 |  |  |  |
Number of contingent value rights per series of contingent value rights | right |  | 1 |  |  |  |
Number of series of contingent value rights issued per share | right |  | 4 |  |  |  |
Entitlement to cash payments (duration) |  | 6 months |  |  |  |
Share-based Compensation [Abstract] |  |  |  |  |  |
Payments to CVR holders |  |  | 900,000 | 0 | 0 |
2019 Convertible Senior Notes |  |  |  |  |  |
Share-based Compensation [Abstract] |  |  |  |  |  |
Principal amount outstanding |  |  | 245,000,000 | 245,000,000 |  |
2019 Convertible Senior Notes | Senior Notes |  |  |  |  |  |
Share-based Compensation [Abstract] |  |  |  |  |  |
Principal amount outstanding |  |  |  |  |  | $ 245,000,000.0
Interest on debt instrument (percent) |  |  |  |  |  | 0.75%
Omthera Pharmaceuticals |  |  |  |  |  |
Estimated amortization expense [Abstract] |  |  |  |  |  |
Revenue recognition, milestone method |  |  | 1,000,000 |  |  |
Proceeds from collaborators |  |  |  | 500,000 |  |
Omthera Pharmaceuticals | Collaborative Arrangement, Product |  |  |  |  |  |
Estimated amortization expense [Abstract] |  |  |  |  |  |
Revenue recognition, milestone method |  |  | 100,000 | 400,000 |  |
Inventories |  |  |  |  |  |
Basis of Presentation [Line Items] |  |  |  |  |  |
Purchase commitment |  |  | 12,300,000 |  |  |
IPR&D |  |  |  |  |  |
Estimated amortization expense [Abstract] |  |  |  |  |  |
Impairment charge |  |  | $ 0 | 0 | $ 480,000.00 |
New Accounting Pronouncement, Early Adoption, Effect |  |  |  |  |  |
Share-based Compensation [Abstract] |  |  |  |  |  |
Other current liabilities |  |  |  | (300,000) |  |
Long-term deferred income taxes |  |  |  | $ 300,000 |  |
Subsequent Event | OMT, Inc. |  |  |  |  |  |
Share-based Compensation [Abstract] |  |  |  |  |  |
Shares issued for acquisition (shares) | shares | 793,594 |  |  |  |  |

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