License and Acquisition Agreements - Novo Nordisk License Agreement (Details) - USD ($) $ in Thousands	1 Months Ended	12 Months Ended
Aug. 31, 2017	Dec. 31, 2019	Dec. 31, 2018
License and Acquisition Agreements
Milestone payments due		$ 0	$ 0
Research and development expense		135,001	86,597
License Agreement \| Novo Nordisk
License and Acquisition Agreements
Upfront payment for exchange of rights	$ 1,500
Consideration payable upon completion of technology transfer	150
Milestone payment payable after achievement of specified milestones	$ 1,000
Research and development expense		$ 0	$ 154

The amount of consideration payable upon completion of the technology transfer.

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- Definition

The amount of milestone payment to be paid by the company upon the achievement of specified clinical, regulatory and sales milestones.

+ References

No definition available.

+ Details

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- Definition

The amount of contractual milestone payments deemed achieved and due.

+ References

No definition available.

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- Definition

The cash outflows associated with upfront payment.

+ References

No definition available.

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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 incurred (1) in a planned search or critical investigation aimed at discovery of new knowledge with the hope that such knowledge will be useful in developing a new product or service, a new process or technique, or in bringing about a significant improvement to an existing product or process; or (2) to translate research findings or other knowledge into a plan or design for a new product or process or for a significant improvement to an existing product or process whether intended for sale or the entity's use, during the reporting period charged to research and development projects, including the costs of developing computer software up to the point in time of achieving technological feasibility, and costs allocated in accounting for a business combination to in-process projects deemed to have no alternative future use.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 985
-SubTopic 20
-Section 50
-Paragraph 1
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-Publisher FASB
-Name Accounting Standards Codification
-Topic 730
-SubTopic 10
-Section 50
-Paragraph 1
-URI http://asc.fasb.org/extlink&oid=6420194&loc=d3e21568-108373

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