Business Overview and Summary of Significant Accounting Policies - Narrative (Details)	12 Months Ended
Dec. 31, 2021 USD ($) product segment	Dec. 31, 2020 USD ($)
New Accounting Pronouncements or Change in Accounting Principle [Line Items]
Number of products approved by the U.S. FDA \| product	9
Number of business segments \| segment	1
Provision for doubtful accounts	$ 0	$ 0
Allowance for doubtful accounts receivable, current	0	0
Up-front and development milestone revenue recognized	42,500,000	$ 276,700,000
Deferred revenue	$ 322,500,000
Three individual customers \| Customer concentration risk \| Accounts receivable
New Accounting Pronouncements or Change in Accounting Principle [Line Items]
Concentration risk, percentage	91.00%	93.00%
United States Government \| Customer concentration risk \| Accounts receivable
New Accounting Pronouncements or Change in Accounting Principle [Line Items]
Concentration risk, percentage	29.00%

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