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

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

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Percentage enrollment in the Lp(a) HORIZON Phase 3 cardiovascular outcome study of pelacarsen.

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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 cash inflow from the sale of common stock, including the premium paid for the purchase of common stock.

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No definition available.

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The number of separate performance obligations under the collaboration agreement.

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

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Royalty percentage received on the sales of a medicine 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, 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) $ in Thousands, shares in Millions	3 Months Ended			12 Months Ended
	Sep. 30, 2021 USD ($)	Mar. 31, 2019 USD ($)	Mar. 31, 2017 USD ($) PerformanceObligation shares	Dec. 31, 2021 USD ($)	Dec. 31, 2020 USD ($)	Dec. 31, 2019 USD ($)	Aug. 31, 2021
Collaborative Arrangement and Licensing Agreement [Abstract]
Revenue				$ 810,456	$ 729,264	$ 1,122,599
Licensing and Other Royalties [Member]
Collaborative Arrangement and Licensing Agreement [Abstract]
Revenue				19,119	8,117	17,205
R&D Revenue [Member]
Collaborative Arrangement and Licensing Agreement [Abstract]
Revenue				468,061	364,565	$ 770,149
Novartis [Member]
Collaborative Arrangement and Licensing Agreement [Abstract]
Upfront payment received			$ 75,000
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 sales milestones				360,000
Cumulative payments received				425,000
Next prospective payment				75,000
Shares issued (in shares) \| shares			1.6
Proceeds from sale of common stock			$ 100,000
Number of separate performance obligations \| PerformanceObligation			4
Transaction price			$ 108,400
Premium received on shares issued			28,400
Potential premium received if common stock is purchased in the future			5,000
Deferred revenue				$ 0	$ 0
Novartis [Member] \| Revenue [Member] \| Strategic Partner [Member]
Collaborative Arrangement and Licensing Agreement [Abstract]
Concentration percentage				3.00%	0.00%	17.00%
Novartis [Member] \| Licensing and Other Royalties [Member]
Collaborative Arrangement and Licensing Agreement [Abstract]
Revenue		$ 150,000
Novartis [Member] \| R&D Services for Pelacarsen [Member]
Collaborative Arrangement and Licensing Agreement [Abstract]
Transaction price			64,000
Novartis [Member] \| R&D Services for Olezarsen [Member]
Collaborative Arrangement and Licensing Agreement [Abstract]
Transaction price			40,100
Novartis [Member] \| Pelacarsen API [Member]
Collaborative Arrangement and Licensing Agreement [Abstract]
Royalty percentage received on sales of medicine				20.00%
Percentage enrollment in Lp(a) HORIZON Phase 3 cardiovascular outcome study							50.00%
Transaction price			1,500
Revenue	$ 25,000
Novartis [Member] \| Olezarsen API [Member]
Collaborative Arrangement and Licensing Agreement [Abstract]
Transaction price			$ 2,800
Novartis [Member] \| R&D Revenue [Member]
Collaborative Arrangement and Licensing Agreement [Abstract]
Revenue				$ 25,500	$ 1,000	$ 187,400