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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No definition available.

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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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No definition available.

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

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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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Amount of revenue recognized that was previously included in balance of obligation to transfer good or service to customer for which consideration from customer has been received or is due.

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The cash inflow associated with the amount received from entity's raising of capital via private rather than public placement.

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Amount, excluding tax collected from customer, of revenue from satisfaction of performance obligation by transferring promised good or service to customer. Tax collected from customer is tax assessed by governmental authority that is both imposed on and concurrent with specific revenue-producing transaction, including, but not limited to, sales, use, value added and excise.

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Strategic Collaboration with Novartis (Details) $ in Thousands		1 Months Ended		3 Months Ended			6 Months Ended
	Jul. 19, 2017 USD ($)	Jul. 31, 2017 USD ($)	Jan. 31, 2017 Drug PerformanceObligation	Jun. 30, 2018 USD ($)	Jun. 30, 2017 USD ($)	Mar. 31, 2017 USD ($)	Jun. 30, 2018 USD ($)	Jun. 30, 2017 USD ($)	Dec. 31, 2017 USD ($)
Strategic Collaboration with Novartis [Abstract]
Proceeds from sale of common stock to Novartis in a private placement	$ 50,000
Revenue earned				$ 18,321	$ 5,713		$ 35,429	$ 11,807
Revenue recognized from deferred revenue				12,600			32,900
AKCEA-APO(a)-L [Member]
Strategic Collaboration with Novartis [Abstract]
Maximum amount of payments receivable for milestones				600,000			600,000
Maximum amount of payments receivable for development milestones				25,000			25,000
Maximum amount of payments receivable for regulatory milestones				290,000			290,000
Maximum amount of payments receivable for commercialization milestones				285,000			$ 285,000
Royalty percentage received on sales of drug							20.00%
Development Services for AKCEA-APO(a)-L [Member]
Strategic Collaboration with Novartis [Abstract]
Transaction price						$ 64,000
Delivery of AKCEA-APO(a)-L [Member]
Strategic Collaboration with Novartis [Abstract]
Transaction price						1,500
AKCEA-APOCIII-L [Member]
Strategic Collaboration with Novartis [Abstract]
Maximum amount of payments receivable for milestones				530,000			$ 530,000
Maximum amount of payments receivable for development milestones				25,000			25,000
Maximum amount of payments receivable for regulatory milestones				240,000			240,000
Maximum amount of payments receivable for commercialization milestones				265,000			$ 265,000
Royalty percentage received on sales of drug							20.00%
Development Services for AKCEA-APOCIII-L [Member]
Strategic Collaboration with Novartis [Abstract]
Transaction price						40,100
Delivery of AKCEA-APOCIII-L [Member]
Strategic Collaboration with Novartis [Abstract]
Transaction price						2,800
R&D Under Collaborative Agreement [Member]
Strategic Collaboration with Novartis [Abstract]
Revenue earned				18,321	5,713		$ 35,429	11,807
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
License fee receivable per drug				150,000			150,000
Next prospective milestone				25,000			$ 25,000
Percentage of license fees, milestone payments and royalties paid as sublicense fee to Ionis							50.00%
Number of separate performance obligations \| PerformanceObligation			4
Transaction price						108,400
Premium received on shares issued by Ionis						28,400
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
Deferred revenue				$ 41,600			$ 41,600		$ 70,700
Novartis [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
Novartis [Member] \| R&D Under Collaborative Agreement [Member]
Strategic Collaboration with Novartis [Abstract]
Revenue earned				$ 18,300	$ 5,700		$ 35,400	$ 11,800