License and Asset Purchase Agreements (Details) $ in Thousands		3 Months Ended			9 Months Ended		12 Months Ended
	Jul. 27, 2020 USD ($) installment	Sep. 30, 2021 USD ($)	Dec. 31, 2020 USD ($)	Sep. 30, 2020 USD ($)	Sep. 30, 2021 USD ($)	Sep. 30, 2020 USD ($)	Dec. 31, 2018 USD ($)	Jan. 11, 2021 USD ($)	Mar. 18, 2020	Nov. 30, 2014
Deferred Revenue Arrangement [Line Items]
Gain on sale of priority review voucher					$ 0	$ 6,300
Merck | License and collaboration revenue
Deferred Revenue Arrangement [Line Items]
Grant revenue		$ 0		$ 74	10	$ 128
License and Collaborative Arrangement | Merck
Deferred Revenue Arrangement [Line Items]
Collaborative arrangement development milestone payments		14,000			14,000
Collaborative arrangement second indication development milestone payments		8,500			8,500
Collaborative arrangement tiered sales milestone payments		80,000			80,000
Net product sales milestone		$ 1,000,000			$ 1,000,000
Value of PRV company is entitled to										60.00%
Value of PRV liability									40.00%
Value of PRV	$ 35,700
License and Collaborative Arrangement | Merck | Held-for-sale or Disposed of by Sale | PRV Transfer Agreement
Deferred Revenue Arrangement [Line Items]
Value of PRV	100,000
Gross proceeds from sale	$ 60,000
Number of installments | installment	2
Cash from sale	$ 34,000
Consideration receivable								$ 26,000
Gain on sale of priority review voucher				$ 6,300
Costs incurred from sale			$ 1,500
License and Collaborative Arrangement | Merck | Minimum
Deferred Revenue Arrangement [Line Items]
Royalty obligation percent of annual product net sales					10.00%
License and Collaborative Arrangement | Merck | Maximum
Deferred Revenue Arrangement [Line Items]
Royalty obligation percent of annual product net sales					12.00%
Ammonett
Deferred Revenue Arrangement [Line Items]
Upfront payments							$ 3,500
Acquisition development milestone payments							17,000
Acquisition specific milestone payments							14,000
Acquisition sales milestone payments							$ 55,000