The license fee payment receivable per drug under the collaboration agreement.

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The maximum amount of payments receivable for commercialization milestones under the collaboration agreement.

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The maximum amount of payments receivable for development milestones under the collaboration agreement.

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The maximum amount of payments receivable for milestones under the collaboration agreement.

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The maximum amount of payments receivable for regulatory milestones under the collaboration agreement.

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The next potential milestone payment to be earned under the collaboration agreement.

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The number of drugs with an exclusive option that could be exercised to develop and commercialize the drug and a license fee is paid under the collaboration agreement. The collaboration partner will assume all further global development, regulatory and commercialization activities for the licensed drug.

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The percentage of license fees, milestone payments and royalties paid as a sublicense fee to Ionis Pharmaceuticals, Inc. under the development, commercialization and license agreement and services agreement .

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The period of time after inception of the collaboration agreement for an initial public offering (IPO) to be completed, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days.

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The amount of the upfront payment received during the period under the collaboration agreement that was paid as a sublicense fee to Ionis Pharmaceuticals, Inc.

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The amount of the upfront payment received during the period under the collaboration agreement that was retained by the entity.

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The potential premium received if common stock is purchased in the future under a Stock Purchase Agreement (SPA) in conjunction with the collaboration agreement.

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The total amount of the premium received over the trading price of common stock at the time of purchase.

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The number of separate performance obligations under the collaboration agreement.

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The amount of consideration the Company is eligible to earn under the collaboration agreement, including any variable consideration.

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Royalty percentage received on the sales of a drug by a collaboration partner under the collaboration agreement.

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Strategic collaboration agreement.

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Sublicense fee payable.

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The amount of upfront payments received during the period under the collaboration agreement.

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Aggregate number of common shares reserved for future issuance.

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For an entity that discloses a concentration risk in relation to quantitative amount, which serves as the "benchmark" (or denominator) in the equation, this concept represents the concentration percentage derived from the division.

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Amount of obligation to transfer good or service to customer for which consideration has been received or is receivable.

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Strategic Collaboration with Novartis (Details) $ in Thousands		1 Months Ended		3 Months Ended
	Feb. 22, 2019 USD ($)	Jul. 31, 2017 USD ($)	Jan. 31, 2017 Drug PerformanceObligation	Mar. 31, 2019 USD ($) shares	Mar. 31, 2018 USD ($)	Mar. 31, 2017 USD ($)	Dec. 31, 2018 USD ($)
Strategic Collaboration with Novartis [Abstract]
Revenue				$ 163,816	$ 17,108
Revenue recognized from deferred revenue				$ 5,500	17,100
Ionis [Member] \| Akcea [Member]
Strategic Collaboration with Novartis [Abstract]
Common stock shares to be issued \| shares				2,837,373
Sublicense fee payable				$ 75,000
Development Services for AKCEA-APO(a)-L [Member]
Strategic Collaboration with Novartis [Abstract]
Transaction price						$ 64,000
Development Services for AKCEA-APOCIII-L [Member]
Strategic Collaboration with Novartis [Abstract]
Transaction price						40,100
Delivery of AKCEA-APO(a)-L [Member]
Strategic Collaboration with Novartis [Abstract]
Transaction price						1,500
Delivery of AKCEA-APOCIII-L [Member]
Strategic Collaboration with Novartis [Abstract]
Transaction price						2,800
Licensing [Member] \| Akcea [Member]
Strategic Collaboration with Novartis [Abstract]
Revenue	$ 150,000
AKCEA-APO(a)-L [Member]
Strategic Collaboration with Novartis [Abstract]
Maximum amount of payments receivable for milestones				675,000
Maximum amount of payments receivable for development milestones				25,000
Maximum amount of payments receivable for regulatory milestones				290,000
Maximum amount of payments receivable for commercialization milestones				$ 360,000
Royalty percentage received on sales of drug				20.00%
AKCEA-APOCIII-L [Member]
Strategic Collaboration with Novartis [Abstract]
Sublicense fee payable				$ 75,000
Maximum amount of payments receivable for milestones				530,000
Maximum amount of payments receivable for development milestones				25,000
Maximum amount of payments receivable for regulatory milestones				240,000
Maximum amount of payments receivable for commercialization milestones				$ 265,000
Royalty percentage received on sales of drug				20.00%
Research and Development and License Revenue Under Collaborative Agreement [Member]
Strategic Collaboration with Novartis [Abstract]
Revenue				$ 157,062	$ 17,108
Novartis [Member]
Strategic Collaboration with Novartis [Abstract]
Upfront payment received						75,000
Portion of upfront payment retained						60,000
Portion of upfront payment paid as sublicense fee to Ionis						15,000
Number of separate performance obligations \| PerformanceObligation			4
Transaction price						108,400
Premium received on shares issued by lonis						28,400
Next prospective milestone				$ 25,000
Percentage of license fees, milestone payments and royalties paid as sublicense fee to lonis				50.00%
Deferred revenue				$ 23,300			$ 28,800
Potential premium received if Ionis common stock is purchased in the future						$ 5,000
Number of months from inception of agreement for IPO to be completed					15 months
Proceeds from sale of common stock to Novartis in a private placement		$ 50,000
Novartis [Member] \| AKCEA-APOCIII-L [Member]
Strategic Collaboration with Novartis [Abstract]
License fee receivable per drug				150,000
Novartis [Member] \| Research and Development and License Revenue Under Collaborative Agreement [Member]
Strategic Collaboration with Novartis [Abstract]
Revenue				$ 157,100	$ 17,100
Novartis [Member] \| Research and Development and License Revenue Under Collaborative Agreement [Member] \| Revenue [Member] \| Strategic Partner [Member]
Strategic Collaboration with Novartis [Abstract]
Concentration percentage				100.00%	100.00%
Novartis [Member] \| Minimum [Member]
Strategic Collaboration with Novartis [Abstract]
Number of drugs with exclusive option that could be exercised \| Drug			1