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Cumulative amount of payments received under the collaboration agreement as of the end of the reporting period.

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No definition available.

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The number of shares received from the subsidiary during the period.

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No definition available.

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The amount of the sublicense fee paid in common stock.

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No definition available.

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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, 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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Collaborative Arrangements and Licensing Agreements, Novartis (Details) - USD ($) $ in Thousands, shares in Millions	3 Months Ended			6 Months Ended
	Jun. 30, 2019	Mar. 31, 2019	Jun. 30, 2018	Jun. 30, 2019	Jun. 30, 2018	Dec. 31, 2018
Collaborative Arrangement and Licensing Agreement [Abstract]
Revenue	$ 163,813		$ 117,747	$ 461,026	$ 262,165
R&D Revenue [Member]
Collaborative Arrangement and Licensing Agreement [Abstract]
Revenue	75,514		$ 60,549	304,640	$ 162,944
Novartis [Member]
Collaborative Arrangement and Licensing Agreement [Abstract]
Deferred revenue	$ 15,800			$ 15,800		$ 28,800
Novartis [Member] \| Revenue [Member] \| Strategic Partner [Member]
Collaborative Arrangement and Licensing Agreement [Abstract]
Concentration percentage	7.00%		16.00%	36.00%	14.00%
Novartis [Member] \| Minimum [Member]
Collaborative Arrangement and Licensing Agreement [Abstract]
Cumulative payments received	$ 343,000			$ 343,000
Novartis [Member] \| AKCEA-APO(a)-L [Member]
Collaborative Arrangement and Licensing Agreement [Abstract]
Revenue		$ 150,000
Novartis [Member] \| R&D Revenue [Member]
Collaborative Arrangement and Licensing Agreement [Abstract]
Revenue	$ 10,700		$ 18,300	$ 167,800	$ 35,400
Akcea [Member]
Collaborative Arrangement and Licensing Agreement [Abstract]
Sublicense fee paid in stock		$ 75,000
Additional shares of Akcea stock received (in shares)		2.8