For contingent consideration arrangements recognized in connection with a business combination, this element represents an estimate of the high-end of the potential range (undiscounted) of the consideration which may be paid.

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- Definition

Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table.

+ References

No definition available.

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- Definition

The aggregate costs related to goods produced and sold and services rendered by an entity during the reporting period. This excludes costs incurred during the reporting period related to financial services rendered and other revenue generating activities.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
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-Topic 220
-SubTopic 10
-Section S99
-Paragraph 2
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- Definition

Indicates type of cost of good or service sold.

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-Publisher FASB
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-Topic 606
-SubTopic 10
-Section 55
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Collaboration Agreements (Details) - USD ($) $ in Millions	12 Months Ended
Collaboration Agreements (Details) - USD ($) $ in Millions	Dec. 31, 2018	Dec. 31, 2017	Dec. 31, 2016
Collaborative Agreements
License fee expense	$ 0.7	$ 0.7	$ 1.6
Type of cost of goods sold line item	us-gaap:LicenseMember	us-gaap:LicenseMember	us-gaap:LicenseMember
Southampton
Collaborative Agreements
Potential milestone payment	$ 1.0
Amgen
Collaborative Agreements
Potential milestone payment	0.9
Yale
Collaborative Agreements
Potential milestone payment	3.0
MedImmune \| Obtaining specified regulatory and development
Collaborative Agreements
Potential milestone payment	45.0
MedImmune \| Specified annual net sales thresholds are met
Collaborative Agreements
Potential milestone payment	$ 125.0