Discontinued Operations - Key Financial Results (Details) - Infectious Disease Business - Disposal Group, Disposed of by Sale, Not Discontinued Operations - USD ($) $ in Thousands	3 Months Ended	9 Months Ended
Sep. 30, 2018	Sep. 30, 2017	Sep. 30, 2018	Sep. 30, 2017
Disposal Group, Including Discontinued Operation, Income Statement Disclosures [Abstract]
Net product revenues	$ 0	$ 9,003	$ (107)	$ 23,635
Operating expenses:
Cost of product revenue	0	5,314	197	12,681
Research and development	24	12,761	534	34,566
Selling, general and administrative	(80)	13,433	2,997	57,400
Total operating expenses	(56)	31,508	3,728	104,647
Loss from operations	56	(22,505)	(3,835)	(81,012)
Gain from sale of business	0	0	168,955	0
Other income (expense), net	(52)	(452)	358	(820)
Income (loss) from discontinued operations before income taxes	4	(22,957)	165,478	(81,832)
Benefit for income taxes	4,003	0	55,236	2
Income (loss) from discontinued operations, net of tax	$ (3,999)	$ (22,957)	$ 110,242	$ (81,834)

Disposal Group, Including Discontinued Operation, Other Income (Expense), Net

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Amount before tax of gain (loss) not previously recognized resulting from the disposal of a discontinued operation.

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