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

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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 is purchased in the future under a Stock Purchase Agreement (SPA) in conjunction with the collaboration agreement.

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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 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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Collaborative Arrangements and Licensing Agreements, Novartis (Details) $ in Thousands, shares in Millions	1 Months Ended	3 Months Ended	12 Months Ended
	Aug. 31, 2021 USD ($)	Mar. 31, 2017 USD ($) PerformanceObligation shares	Dec. 31, 2022 USD ($)	Dec. 31, 2021 USD ($)	Dec. 31, 2020 USD ($)	Jan. 31, 2023
Collaborative Arrangement and Licensing Agreement [Abstract]
Revenue			$ 587,367	$ 810,456	$ 729,264
Pelacarsen API [Member] \| Subsequent Event [Member]
Collaborative Arrangement and Licensing Agreement [Abstract]
Percentage of royalty payments paid to Royalty Pharma on annual sales of medicine						25.00%
R&D Revenue [Member]
Collaborative Arrangement and Licensing Agreement [Abstract]
Revenue			284,009	468,061	$ 364,565
Novartis [Member]
Collaborative Arrangement and Licensing Agreement [Abstract]
Maximum amount of payments receivable over term of collaboration			900,000
Upfront payment received		$ 75,000
Maximum amount of license fees over term of collaboration			150,000
Maximum amount of development milestone payments over term of collaboration			25,000
Maximum amount of regulatory milestone payments over term of collaboration			290,000
Maximum amount of sales milestone payments over term of collaboration			360,000
Cumulative payments received			275,000
Next payment to be achieved			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			0.00%	3.00%	0.00%
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			$ 200	$ 25,500	$ 1,000