Organization and Summary of Significant Accounting Policies (Details) $ in Thousands	12 Months Ended
	Dec. 31, 2020 USD ($) item segment	Dec. 31, 2019 USD ($)	Dec. 31, 2018 USD ($)
Concentrations of Credit Risk
Number of Operating Segments | segment	1
Accounts Receivable
Allowance for doubtful accounts	$ 0	$ 0
Variable Interest Entities
Number of entities in which variable interest held | item	0
Percentage of MediCare Part D Insurance Coverage Gap Required to be Funded by Manufacturers	70.00%
Medicare Part D Insurance Coverage Gap, Increase in Eligible Patient Spending, Percentage	30.00%
Advertising Expenses
Advertising expenses	$ 28,900	$ 15,300	$ 10,600
MorphoSys AG
Variable Interest Entities
Collaboration Agreement Profit Loss Sharing Ratio	50.00%
JAKAFI
Inventory
Shelf life for finished goods inventory, maximum	36 months
ICLUSIG
Inventory
Shelf life for finished goods inventory, maximum	36 months
Variable Interest Entities
Amortization period	12 years 6 months
PEMAZYRE
Inventory
Period of lower average per unit cost of materials	48 months
Shelf life for finished goods inventory, maximum	36 months