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Basis of Presentation and Summary of Significant Accounting Policies - Narrative (Details) |  | 1 Months Ended | 12 Months Ended |  |  |  |  |
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May 31, 2017 USD ($) | May 31, 2019 USD ($) | Dec. 31, 2018 USD ($) | Dec. 31, 2019 USD ($) | Dec. 31, 2018 USD ($) | Dec. 31, 2017 USD ($) | Dec. 31, 2007 $ / shares | Aug. 15, 2019 USD ($) | Jan. 01, 2019 USD ($) | May 31, 2018 USD ($) | Oct. 06, 2017 USD ($) | Jan. 31, 2010 right
Basis of Presentation [Line Items] |  |  |  |  |  |  |  |  |  |  |  |
Maturity period of cash and cash equivalents, maximum |  |  |  | 3 months |  |  |  |  |  |  |  |
Write-downs related to obsolete inventory |  |  |  | $ 0 | $ 0 | $ 0 |  |  |  |  |  |
Other income (expense), net |  |  |  | (6,010,000) | (6,307,000) | $ 2,603,000 |  |  |  |  |  |
Revenue recognized |  |  |  | 3,300,000 | 2,300,000 |  |  |  |  |  |  |
Milestone payment received |  |  |  | 4,600,000 |  |  |  |  |  |  |  |
Third-party portion of milestone payment received |  |  |  | 4,000,000.0 |  |  |  |  |  |  |  |
Share-based Compensation |  |  |  |  |  |  |  |  |  |  |  |
Dividend declared (USD per share) | $ / shares |  |  |  |  |  |  | $ 2.50 |  |  |  |  |
Operating lease right-of-use assets |  |  | $ 0 | 10,353,000 | 0 |  |  |  |  |  |  |
Operating lease liability |  |  |  | $ 11,212,000 |  |  |  |  |  |  |  |
Stock Options | 2002 Stock Incentive Plan |  |  |  |  |  |  |  |  |  |  |  |
Share-based Compensation |  |  |  |  |  |  |  |  |  |  |  |
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 |  |  |  |  |  |  |  |  |  |  |  |
Award vesting period |  |  |  | 6 months |  |  |  |  |  |  |  |
Award vesting right (as a percent) |  |  |  | 12.50% |  |  |  |  |  |  |  |
Stock Options | Vest 1/48 each month for forty-two months | 2002 Stock Incentive Plan |  |  |  |  |  |  |  |  |  |  |  |
Share-based Compensation |  |  |  |  |  |  |  |  |  |  |  |
Award vesting period |  |  |  | 42 months |  |  |  |  |  |  |  |
Award vesting right (as a percent) |  |  |  | 2.08% |  |  |  |  |  |  |  |
Minimum |  |  |  |  |  |  |  |  |  |  |  |
Basis of Presentation [Line Items] |  |  |  |  |  |  |  |  |  |  |  |
Property and equipment, useful life |  |  |  | 3 years |  |  |  |  |  |  |  |
Maximum |  |  |  |  |  |  |  |  |  |  |  |
Basis of Presentation [Line Items] |  |  |  |  |  |  |  |  |  |  |  |
Property and equipment, useful life |  |  |  | 10 years |  |  |  |  |  |  |  |
Crystal |  |  |  |  |  |  |  |  |  |  |  |
Basis of Presentation [Line Items] |  |  |  |  |  |  |  |  |  |  |  |
Value of share consideration |  |  |  |  |  |  |  |  |  |  | $ 10,500,000 |
Metabasis Therapeutics |  |  |  |  |  |  |  |  |  |  |  |
Basis of Presentation [Line Items] |  |  |  |  |  |  |  |  |  |  |  |
Number of contingent value rights | right |  |  |  |  |  |  |  |  |  |  |  | 4
Royalty Agreements |  |  |  |  |  |  |  |  |  |  |  |
Basis of Presentation [Line Items] |  |  |  |  |  |  |  |  |  |  |  |
Product royalty (as a percent) | 20.00% |  |  |  |  |  |  |  |  |  |  |
Revenue recognized |  |  |  | $ 600,000 |  |  |  |  |  |  |  |
Novan | Royalty Agreements |  |  |  |  |  |  |  |  |  |  |  |
Basis of Presentation [Line Items] |  |  |  |  |  |  |  |  |  |  |  |
Additional royalties receivable under sales-based milestones |  | $ 20,000,000.0 |  |  |  |  |  |  |  |  |  |
Novan | Royalty Agreements | Minimum |  |  |  |  |  |  |  |  |  |  |  |
Basis of Presentation [Line Items] |  |  |  |  |  |  |  |  |  |  |  |
Product royalty (as a percent) |  | 7.00% |  |  |  |  |  |  |  |  |  |
Novan | Royalty Agreements | Maximum |  |  |  |  |  |  |  |  |  |  |  |
Basis of Presentation [Line Items] |  |  |  |  |  |  |  |  |  |  |  |
Product royalty (as a percent) |  | 10.00% |  |  |  |  |  |  |  |  |  |
Novan | Licensing Agreements |  |  |  |  |  |  |  |  |  |  |  |
Basis of Presentation [Line Items] |  |  |  |  |  |  |  |  |  |  |  |
Upfront payment for license |  | $ 12,000,000.0 |  |  |  |  |  |  |  |  |  |
Palvella | Royalty Agreements |  |  |  |  |  |  |  |  |  |  |  |
Basis of Presentation [Line Items] |  |  |  |  |  |  |  |  |  |  |  |
Additional royalties receivable under sales-based milestones |  |  | $ 8,000,000.0 |  | $ 8,000,000.0 |  |  |  |  |  |  |
Palvella | Royalty Agreements | Minimum |  |  |  |  |  |  |  |  |  |  |  |
Basis of Presentation [Line Items] |  |  |  |  |  |  |  |  |  |  |  |
Product royalty (as a percent) |  |  | 5.00% |  | 5.00% |  |  |  |  |  |  |
Palvella | Royalty Agreements | Maximum |  |  |  |  |  |  |  |  |  |  |  |
Basis of Presentation [Line Items] |  |  |  |  |  |  |  |  |  |  |  |
Product royalty (as a percent) |  |  | 9.80% |  | 9.80% |  |  |  |  |  |  |
Palvella | Licensing Agreements |  |  |  |  |  |  |  |  |  |  |  |
Basis of Presentation [Line Items] |  |  |  |  |  |  |  |  |  |  |  |
Upfront payment for license |  |  | $ 10,000,000.0 |  |  |  |  |  |  |  |  |
Aziyo | Royalty Agreements |  |  |  |  |  |  |  |  |  |  |  |
Basis of Presentation [Line Items] |  |  |  |  |  |  |  |  |  |  |  |
Product royalty (as a percent) | 5.00% |  |  |  |  |  |  |  |  |  |  |
Proceeds from royalties received | $ 10,000,000.0 |  |  |  |  |  |  |  |  |  |  |
Effective interest rate of forecasted cash flows (as a percent) |  |  |  | 23.00% |  |  |  |  |  |  |  |
Aziyo | Royalty Agreements | Maximum |  |  |  |  |  |  |  |  |  |  |  |
Basis of Presentation [Line Items] |  |  |  |  |  |  |  |  |  |  |  |
Additional royalties receivable under sales-based milestones | $ 10,000,000.0 |  |  |  |  |  |  |  |  |  |  |
CorMatrix | Royalty Agreements |  |  |  |  |  |  |  |  |  |  |  |
Basis of Presentation [Line Items] |  |  |  |  |  |  |  |  |  |  |  |
Product royalty (as a percent) | 5.00% |  |  |  |  |  |  |  |  |  |  |
Expiration period of royalty agreement | 10 years |  |  |  |  |  |  |  |  |  |  |
Selexis |  |  |  |  |  |  |  |  |  |  |  |
Basis of Presentation [Line Items] |  |  |  |  |  |  |  |  |  |  |  |
Other income (expense), net |  |  |  | $ (5,100,000) |  |  |  |  |  |  |  |
2023 Convertible Senior Notes | Senior Notes |  |  |  |  |  |  |  |  |  |  |  |
Share-based Compensation |  |  |  |  |  |  |  |  |  |  |  |
Principal amount outstanding |  |  |  |  |  |  |  |  |  | $ 750,000,000.0 |  |
Interest on debt instrument (as a percent) |  |  |  |  |  |  |  |  |  | 0.75% |  |
2019 Convertible Senior Notes |  |  |  |  |  |  |  |  |  |  |  |
Share-based Compensation |  |  |  |  |  |  |  |  |  |  |  |
Derivative asset |  |  |  |  |  |  |  | $ 0 |  |  |  |
Derivative liability |  |  |  |  |  |  |  | $ 0 |  |  |  |
Accounting Standards Update 2016-02 |  |  |  |  |  |  |  |  |  |  |  |
Share-based Compensation |  |  |  |  |  |  |  |  |  |  |  |
Operating lease right-of-use assets |  |  |  |  |  |  |  |  | $ 5,200,000 |  |  |
Operating lease liability |  |  |  |  |  |  |  |  | $ 5,900,000 |  |  |
Dividend yield |  |  |  |  |  |  |  |  |  |  |  |
Share-based Compensation |  |  |  |  |  |  |  |  |  |  |  |
Measurement input |  |  |  | 0 |  |  |  |  |  |  |  |

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