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Revenue from arrangements that include licensing and royalty revenues and profit sharing payments. Licensing revenue represents revenue earned during the period relating to consideration received from another party for the right to use, but not own, certain of the entity's intangible assets. Licensing arrangements typically include, but are not limited to, rights to use intellectual property on an exclusive or non-exclusive basis. Royalty, profit sharing and/or earn out payments are derived from a percentage or stated amount of sales proceeds or revenue generated by the third party using the entity's intellectual property.

No definition available.

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Revenue recognized during the period from collaborations where the entity receives payments for expenditures relating to research and development activities, contractual milestone payments, and the manufacture and sale of drug inventory to collaboration partners.

No definition available.

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Sum of the carrying amounts as of the balance sheet date of all assets that are recognized. Assets are probable future economic benefits obtained or controlled by an entity as a result of past transactions or events.

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 944
-SubTopic 210
-Section S99
-Paragraph 1
-Subparagraph (SX 210.7-03(a)(12))
-URI http://asc.fasb.org/extlink&oid=6879938&loc=d3e572229-122910

Reference 2: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 942
-SubTopic 210
-Section S99
-Paragraph 1
-Subparagraph (SX 210.9-03(11))
-URI http://asc.fasb.org/extlink&oid=6876686&loc=d3e534808-122878

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Number of segments reported by the entity. A reportable segment is a component of an entity for which there is an accounting requirement to report separate financial information on that component in the entity's financial statements.

No definition available.

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Generally recurring costs associated with normal operations except for the portion of these expenses which can be clearly related to production and included in cost of sales or services. Includes selling, general and administrative expense.

No definition available.

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The net result for the period of deducting operating expenses from operating revenues.

No definition available.

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Amount of revenue recognized from goods sold, services rendered, insurance premiums, or other activities that constitute an earning process. Includes, but is not limited to, investment and interest income before deduction of interest expense when recognized as a component of revenue, and sales and trading gain (loss).

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 225
-SubTopic 10
-Section S99
-Paragraph 2
-Subparagraph (SX 210.5-03.1)
-URI http://asc.fasb.org/extlink&oid=63488584&loc=d3e20235-122688

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Revenue earned during the period from the leasing or otherwise lending to a third party the entity's rights or title to certain property. Royalty revenue is derived from a percentage or stated amount of sales proceeds or revenue generated by the third party using the entity's property. Examples of property from which royalties may be derived include patents and oil and mineral rights.

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 225
-SubTopic 10
-Section S99
-Paragraph 2
-Subparagraph (SX 210.5-03.1(e))
-URI http://asc.fasb.org/extlink&oid=63488584&loc=d3e20235-122688

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- References

No definition available.

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Percentage of subsidiary's or equity investee's stock owned by parent company after stock transaction.

No definition available.

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Percentage of subsidiary's or equity investee's stock owned by parent company before stock transaction.

No definition available.

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- References

No definition available.

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Name:	us-gaap_StatementBusinessSegmentsAxis=ions_IonisCoreMember
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Name:	us-gaap_StatementBusinessSegmentsAxis=ions_AkceaTherapeuticsMember
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Name:	us-gaap_ConsolidationItemsAxis=us-gaap_IntersegmentEliminationMember
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