Quarterly report pursuant to Section 13 or 15(d)

Basis of Presentation and Summary of Significant Accounting Policies - Narrative (Details)

v3.19.1
Basis of Presentation and Summary of Significant Accounting Policies - Narrative (Details) - USD ($)
$ / shares in Units, $ in Thousands, shares in Millions
1 Months Ended 3 Months Ended
Dec. 31, 2018
Mar. 31, 2019
Jan. 01, 2019
Mar. 31, 2018
Dec. 31, 2017
Property, Plant and Equipment [Line Items]          
Right-of-use assets   $ 4,881      
Lease liabilities   5,507      
Total assets $ 656,665 1,396,316      
Level 1          
Property, Plant and Equipment [Line Items]          
Total assets 56,774 $ 80,181      
Viking Therapeutics, Inc.          
Property, Plant and Equipment [Line Items]          
Equity ownership interest (as a percent)       12.40%  
Outstanding warrants to purchase shares of Viking's common stock (shares)   1.5      
Warrant exercise price (USD per share)   $ 1.50      
Recurring | Level 1 | Investment in Warrants          
Property, Plant and Equipment [Line Items]          
Total assets   $ 12,700     $ 9,300
Accounting Standards Update 2016-02          
Property, Plant and Equipment [Line Items]          
Right-of-use assets     $ 5,200    
Lease liabilities     $ 5,900    
Royalty Agreements | Aziyo          
Property, Plant and Equipment [Line Items]          
Effective interest rate for forecasted cash flows (as a percent)   23.00%      
Commercial license rights          
Property, Plant and Equipment [Line Items]          
Definite lived intangible assets 36,298 $ 38,298      
Commercial license rights | Palvella          
Property, Plant and Equipment [Line Items]          
Contract asset 8,000        
Definite lived intangible assets $ 10,000 $ 10,000      
Minimum | Royalty Agreements | Palvella          
Property, Plant and Equipment [Line Items]          
Tiered royalty rate (as a percent) 5.00%        
Maximum | Royalty Agreements | Palvella          
Property, Plant and Equipment [Line Items]          
Tiered royalty rate (as a percent) 9.80%