Amount of interest expense using the effective interest rate method related to the sale of future royalties.

No definition available.

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- Definition

Amount, before accumulated amortization, of the liability related to the sale of future royalties, pursuant to a royalty purchase agreement, that the Company is entitled to receive under collaboration agreements with Biogen and Novartis. The balance will be amortized over the estimated life of the arrangement using the effective interest rate method.

+ References

No definition available.

+ Details

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- Definition

Amount, after accumulated amortization, of the unamortized liability related to the sale of future royalties, pursuant to a royalty purchase agreement, that the Company is entitled to receive under collaboration agreements with Biogen and Novartis. The balance will be amortized over the estimated life of the arrangement using the effective interest rate method.

+ References

No definition available.

+ Details

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- Definition

The maximum amount of annual sales on which royalty payments are paid under the royalty purchase agreement.

+ References

No definition available.

+ Details

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- Definition

The maximum amount of payments receivable for additional milestones under the royalty purchase agreement.

+ References

No definition available.

+ Details

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Data Type:	xbrli:monetaryItemType
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- Definition

Maximum royalty payments under the royalty purchase agreement made before royalty interest reverts back to the Company.

+ References

No definition available.

+ Details

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- Definition

The cash outflow paid to third parties for transaction costs in connection with a monetization transaction of future SPINRAZA and pelacarsen royalties the Company is entitled to under collaboration and licensing agreements.

+ References

No definition available.

+ Details

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- Definition

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

+ References

No definition available.

+ Details

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- Definition

The cash inflow from the sale of future royalties under a royalty purchase agreement.

+ References

No definition available.

+ Details

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Data Type:	xbrli:monetaryItemType
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- References

No definition available.

+ Details

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- Definition

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

+ References

No definition available.

+ Details

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Data Type:	xbrli:monetaryItemType
Balance Type:	debit
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- Definition

Effective interest rate for the funds borrowed under the debt agreement considering interest compounding and original issue discount or premium.

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 470
-SubTopic 20
-Section 50
-Paragraph 6
-Subparagraph (a)
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Reference 2: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 835
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-Section 45
-Paragraph 2
-URI https://asc.fasb.org/extlink&oid=124435984&loc=d3e28551-108399

Reference 3: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 835
-SubTopic 30
-Section 50
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-URI https://asc.fasb.org/extlink&oid=124429444&loc=SL124452920-239629

Reference 4: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 210
-SubTopic 10
-Section S99
-Paragraph 1
-Subparagraph (SX 210.5-02.22(a)(1))
-URI https://asc.fasb.org/extlink&oid=120391452&loc=d3e13212-122682

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- Definition

Amount, after accumulated amortization, of debt issuance costs. Includes, but is not limited to, legal, accounting, underwriting, printing, and registration costs.

+ References

Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 470
-SubTopic 20
-Section 50
-Paragraph 1D
-Subparagraph (a)
-URI https://asc.fasb.org/extlink&oid=123466505&loc=SL123495340-112611

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-Publisher FASB
-Name Accounting Standards Codification
-Topic 835
-SubTopic 30
-Section 45
-Paragraph 3
-URI https://asc.fasb.org/extlink&oid=124435984&loc=d3e28555-108399

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Liability Related to Sale of Future Royalties (Details) - USD ($) $ in Thousands	1 Months Ended	3 Months Ended
	Jan. 31, 2023	Mar. 31, 2023	Mar. 31, 2022
Royalty Revenue Monetization [Abstract]
Transaction costs		$ 10,434	$ 0
Proceeds from sale of future royalties		500,000	0
Interest expense related to sale of future royalties		15,363	$ 0
Net liability related to sale of future royalties		505,081
Royalty Purchase Agreement [Member]
Royalty Revenue Monetization [Abstract]
Upfront payment received	$ 500,000
Maximum amount of payments receivable for additional milestones		$ 625,000
Effective interest rate		13.50%
Transaction costs		$ 10,400
Proceeds from sale of future royalties		500,000
Interest expense related to sale of future royalties		15,363
Liability related to sale of future royalties as of		515,363
Net issuance costs related to sale of future royalties		(10,282)
Net liability related to sale of future royalties		505,081
Royalty Purchase Agreement [Member] \| SPINRAZA [Member]
Royalty Revenue Monetization [Abstract]
Maximum amount of annual sales on which royalty payments are paid		$ 1,500,000
Royalty Purchase Agreement [Member] \| SPINRAZA [Member] \| Minimum [Member]
Royalty Revenue Monetization [Abstract]
Percentage of royalty payments paid on annual sales of medicine		25.00%
Maximum royalty payments made before royalty interest reverts back		$ 475,000
Royalty Purchase Agreement [Member] \| SPINRAZA [Member] \| Maximum [Member]
Royalty Revenue Monetization [Abstract]
Percentage of royalty payments paid on annual sales of medicine		45.00%
Maximum royalty payments made before royalty interest reverts back		$ 550,000
Royalty Purchase Agreement [Member] \| Pelacarsen [Member]
Royalty Revenue Monetization [Abstract]
Percentage of royalty payments paid on annual sales of medicine		25.00%