Basis of Presentation and Summary of Significant Accounting Policies - Narrative (Details)		1 Months Ended		12 Months Ended
	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