Agreements - Biotest (Details) - USD ($)	1 Months Ended	3 Months Ended												12 Months Ended
	Sep. 30, 2008	Dec. 31, 2019	Sep. 30, 2019	Jun. 30, 2019	Mar. 31, 2019	Dec. 31, 2018	Sep. 30, 2018	Jun. 30, 2018	Mar. 31, 2018	Dec. 31, 2017	Sep. 30, 2017	Jun. 30, 2017	Mar. 31, 2017	Dec. 31, 2019	Dec. 31, 2018	Dec. 31, 2017	Dec. 31, 2006
Collaborative Agreements disclosures
Revenue from contract with customer		$ 44,864,000	$ 13,281,000	$ 15,542,000	$ 8,584,000	$ 13,416,000	$ 10,928,000	$ 9,287,000	$ 19,815,000	$ 39,448,000	$ 8,480,000	$ 39,020,000	$ 28,499,000	$ 82,271,000	$ 53,446,000	$ 115,447,000
Biotest | Development milestones
Collaborative Agreements disclosures
Potential milestone payment																	$ 4,500,000
Biotest | Phase IIb Clinical Trial
Collaborative Agreements disclosures
Potential milestone payment		2,000,000												2,000,000
Biotest | Regulatory milestones
Collaborative Agreements disclosures
Potential milestone payment																	31,000,000
Biotest | Milestone payments
Collaborative Agreements disclosures
Revenue from contract with customer	$ 500,000
License and milestone fees
Collaborative Agreements disclosures
Revenue from contract with customer		$ 29,551,000	$ 79,000	5,079,000	79,000	1,747,000	672,000	1,321,000	11,540,000	29,580,000	79,000	31,080,000	18,730,000	34,788,000	15,280,000	79,469,000
License and milestone fees | Biotest
Collaborative Agreements disclosures
Potential milestone payment																	35,500,000
Upfront payment | Biotest
Collaborative Agreements disclosures
Revenue from contract with customer																	$ 1,000,000
Research and development support
Collaborative Agreements disclosures
Revenue from contract with customer				$ 51,000	$ 17,000	$ 218,000	$ 388,000	$ 388,000	$ 383,000	$ 452,000	$ 650,000	$ 902,000	$ 1,478,000	$ 68,000	$ 1,377,000	$ 3,482,000