Collaborative Arrangements and Licensing Agreements, PTC Therapeutics (Details) - Akcea [Member] - PTC Therapeutics [Member] - Subsequent Event [Member] $ in Millions	Aug. 07, 2018 USD ($)
Collaborative Arrangement and Licensing Agreement [Abstract]
Upfront payment to be received	$ 18
Upfront payment due in third quarter of 2018	12
Upfront payment to be paid on earlier of FDA or EMA approval of WAYLIVRA	6
Maximum amount of payments receivable per drug for regulatory milestones	$ 8
Royalty percentage received on net sales of each drug in Latin America from PTC	20.00%
Period before PTC pays royalties on net sales of product after first commercial sale in Brazil	12 months
Minimum revenue recognized in Latin America by PTC before paying royalties	$ 10

No definition available.

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- Definition

The maximum amount of payments receivable per drug or program for regulatory milestone payments under the collaboration agreement.

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No definition available.

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Period of time before collaboration partner pays royalties on net sales of product after first commercial sale in Brazil, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days.

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The minimum amount of revenue recognized in Latin America by the collaboration partner before paying royalties.

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Royalty percentage received on the net sales of each drug in Latin America from the collaboration partner under the collaboration agreement.

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No definition available.

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- Definition

The amount of the upfront payment expected to be received in the near term under the collaboration agreement.

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No definition available.

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- Definition

The amount of the upfront payment to be paid on the earlier of approval by the U.S. Food and Drug Administration (FDA) or the European Medicines Agency (EMA) under the collaboration agreement.

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No definition available.

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- Definition

The total amount of upfront payments expected to be received under the collaboration agreement.

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No definition available.

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