Annual report pursuant to Section 13 and 15(d)

Agenus Royalty Purchase Agreement (Details)

v3.10.0.1
Agenus Royalty Purchase Agreement (Details)
$ in Thousands
 12 Months Ended
Sep. 20, 2018
USD ($)
LicensedProduct
Dec. 31, 2018
USD ($)
Royalty Purchase Agreement [Line Items]    
Long-term royalty receivables   $ 15,000
Royalty Purchase Agreement [Member] | Agenus [Member]    
Royalty Purchase Agreement [Line Items]    
Payments to acquire milestones and royalties   15,000
Long-term royalty receivables   15,000
Royalty Purchase Agreement [Member] | Agenus [Member] | Silicon Valley Bank [Member]    
Royalty Purchase Agreement [Line Items]    
Loan borrowed   $ 7,500
Royalty Purchase Agreement [Member] | Agenus [Member] | Incyte [Member]    
Royalty Purchase Agreement [Line Items]    
Number of licensed products related to milestone and royalties | LicensedProduct 6  
Royalty Purchase Agreement [Member] | Agenus [Member] | Merck [Member]    
Royalty Purchase Agreement [Line Items]    
Number of licensed products related to milestone and royalties | LicensedProduct 1  
Royalty Purchase Agreement [Member] | Agenus [Member] | Incyte and Merck [Member]    
Royalty Purchase Agreement [Line Items]    
Purchased eligible milestone payments receivable upon achievement of potential development, regulatory and commercial milestones $ 59,500  
Royalty Purchase Agreement [Member] | Agenus [Member] | Right to Receive Low-Single Mid-Teen Royalties [Member] | Incyte [Member]    
Royalty Purchase Agreement [Line Items]    
Purchased percentage of royalties on net sales of products 33.00%  
Purchased percentage of milestones 10.00%  
Royalty Purchase Agreement [Member] | Agenus [Member] | Right to Receive Low Single Digit Royalties [Member] | Merck [Member]    
Royalty Purchase Agreement [Line Items]    
Purchased percentage of royalties on net sales of products 33.00%  
Purchased percentage of milestones 10.00%