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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 development milestone payments to be received over the term of the collaboration.

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The maximum amount of license fees to be received over the term of the collaboration.

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The maximum amount of payments the Company is eligible to receive over the term of the collaboration.

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The maximum amount of regulatory milestone payments to be received over the term of the collaboration.

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The maximum amount of sales milestone payments to be received over the term of the collaboration.

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The next payment to be achieved under the collaboration agreement.

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The percentage of royalty payments paid on annual sales of medicine.

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The potential premium received if common stock was 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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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 net 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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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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Collaborative Arrangements and Licensing Agreements, Novartis (Details) $ in Thousands, shares in Millions	3 Months Ended	12 Months Ended
	Dec. 31, 2023 USD ($)	Dec. 31, 2023 USD ($)	Dec. 31, 2022 USD ($)	Dec. 31, 2021 USD ($)	Dec. 31, 2017 USD ($) shares	Aug. 31, 2023 PerformanceObligation	Mar. 31, 2017 PerformanceObligation
Collaborative Arrangement and Licensing Agreement [Abstract]
Revenue		$ 787,647	$ 587,367	$ 810,456
Pelacarsen API [Member]
Collaborative Arrangement and Licensing Agreement [Abstract]
Percentage of royalty payments paid to Royalty Pharma on annual sales of medicine	25.00%	25.00%
Pelacarsen [Member]
Collaborative Arrangement and Licensing Agreement [Abstract]
Maximum amount of payments receivable over term of collaboration	$ 900,000	$ 900,000
Upfront payment received					$ 75,000
Maximum amount of license fees over term of collaboration	150,000	150,000
Maximum amount of development milestone payments over term of collaboration	25,000	25,000
Maximum amount of regulatory milestone payments over term of collaboration	290,000	290,000
Maximum amount of sales milestone payments over term of collaboration	360,000	360,000
Cumulative payments received	275,000	275,000
Next payment to be achieved	50,000	50,000
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 was purchased in the future					5,000
Revenue		30,194	237	$ 25,526
Deferred revenue	30,000	$ 30,000	$ 0
Pelacarsen [Member] \| Revenue [Member] \| Strategic Partner [Member]
Collaborative Arrangement and Licensing Agreement [Abstract]
Concentration percentage		4.00%		3.00%
Pelacarsen [Member] \| Maximum [Member] \| Revenue [Member] \| Strategic Partner [Member]
Collaborative Arrangement and Licensing Agreement [Abstract]
Concentration percentage			1.00%
Pelacarsen [Member] \| R&D Services for Pelacarsen [Member]
Collaborative Arrangement and Licensing Agreement [Abstract]
Transaction price					64,000
Pelacarsen [Member] \| R&D Services for Olezarsen [Member]
Collaborative Arrangement and Licensing Agreement [Abstract]
Transaction price					40,100
Pelacarsen [Member] \| Pelacarsen API [Member]
Collaborative Arrangement and Licensing Agreement [Abstract]
Royalty percentage received on net sales of medicine		20.00%
Transaction price					1,500
Pelacarsen [Member] \| Olezarsen API [Member]
Collaborative Arrangement and Licensing Agreement [Abstract]
Transaction price					$ 2,800
Lp(a)-Driven Cardiovascular Disease [Member]
Collaborative Arrangement and Licensing Agreement [Abstract]
Maximum amount of payments receivable over term of collaboration	730,000	$ 730,000
Upfront payment received	60,000
Maximum amount of development milestone payments over term of collaboration	155,000	155,000
Maximum amount of regulatory milestone payments over term of collaboration	105,000	105,000
Maximum amount of sales milestone payments over term of collaboration	410,000	410,000
Cumulative payments received	60,000	60,000
Next payment to be achieved	5,000	5,000
Number of separate performance obligations \| PerformanceObligation						1
Transaction price	$ 60,000	$ 60,000
Lp(a)-Driven Cardiovascular Disease [Member] \| Minimum [Member]
Collaborative Arrangement and Licensing Agreement [Abstract]
Royalty percentage received on net sales of medicine		10.00%
Lp(a)-Driven Cardiovascular Disease [Member] \| Maximum [Member]
Collaborative Arrangement and Licensing Agreement [Abstract]
Royalty percentage received on net sales of medicine		20.00%