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Represents the average period for completion of an animal study or clinical trial.

No definition available.

Name:	ions_AverageDurationToCompletion
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The amount of change to the allocation of the consideration to a specific unit of accounting that would result from a specified change in the selling price factor applied to a multiple-deliverable arrangement.

No definition available.

Name:	ions_ChangeInAmountOfRevenueFromProductForAssumedChangeInSellingPrice
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Data Type:	xbrli:monetaryItemType
Balance Type:	debit
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Revenue from arrangements that include licensing and royalty revenues, profit sharing and/or earn out 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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Represents the number of categories of milestone events.

No definition available.

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Represents the number of stages in the life-cycle of drugs, reflected in the categories of contractual milestones.

No definition available.

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Represents the number of active collaborations with the collaborative partner.

No definition available.

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Represents the number of targets for the research and development of drugs under a collaborative agreement.

No definition available.

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The percentage change to the allocation of the consideration to a specific unit of accounting that would result from a specified change in the selling price factor applied to a multiple-deliverable arrangement.

No definition available.

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Represents the typical period within which approval is obtained once regulatory filings have been prepared and submitted.

No definition available.

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Represents the typical period within which regulatory filings are prepared and submitted.

No definition available.

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Represents a pre-specified sales threshold that could be used as a pre-specified event to trigger a milestone payment.

No definition available.

Name:	ions_PreSpecifiedSalesThreshold
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Represents the number of separate units of accounting requiring the allocation of consideration for revenue recognition purposes under the multi-deliverable arrangement.

No definition available.

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Data Type:	xbrli:integerItemType
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Term of the collaboration agreement, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days.

No definition available.

Name:	ions_TermOfCollaborationAgreement
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Represents the amount of upfront fees received during the period under the agreement.

No definition available.

Name:	ions_UpfrontFeeReceived
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Data Type:	xbrli:monetaryItemType
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The portion of upfront fees received during the period under the terms of the agreement that are recognized as revenue during the period.

No definition available.

Name:	ions_UpfrontFeeRecognized
Namespace Prefix:	ions_
Data Type:	xbrli:monetaryItemType
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Amount of deferred revenue recognized for transactions arising during the current reporting period. Deferred revenue is a liability as of the balance sheet date related to a revenue producing activity for which revenue has not yet been recognized. Generally, an Entity records deferred revenue when it receives consideration from a customer before achieving certain criteria that must be met for revenue to be recognized in conformity with GAAP.

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 605
-SubTopic 10
-Section S99
-Paragraph 1
-Subparagraph (SAB TOPIC 13.A.4(a).Q1)
-URI http://asc.fasb.org/extlink&oid=27012821&loc=d3e214044-122780

Reference 2: http://www.xbrl.org/2003/role/presentationRef
-Publisher SEC
-Name Staff Accounting Bulletin (SAB)
-Number Topic 13
-Section A

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- References

No definition available.

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Name:	us-gaap_RangeAxis=us-gaap_MinimumMember
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Name:	us-gaap_RangeAxis=us-gaap_MaximumMember
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Data Type:	na
Balance Type:
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Name:	ions_AchievementOfMilestoneAxis=ions_DevelopmentMilestonesPhaseOneMember
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Name:	ions_AchievementOfMilestoneAxis=ions_DevelopmentMilestonesPhaseTwoMember
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Name:	ions_AchievementOfMilestoneAxis=ions_DevelopmentMilestonesPhaseThreeMember
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Data Type:	na
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Name:	ions_AchievementOfMilestoneAxis=ions_RegulatoryMilestonesMember
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Name:	ions_AchievementOfMilestoneAxis=ions_CommercializationMilestonesMember
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Name:	us-gaap_CounterpartyNameAxis=ions_BayerHealthCareMember
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Data Type:	na
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Name:	us-gaap_TypeOfArrangementAxis=ions_AgreementEnteredIntoInMay2015Member
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Name:	us-gaap_CounterpartyNameAxis=ions_BiogenMember
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Name:	us-gaap_ProductOrServiceAxis=ions_NusinersenMember
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Name:	us-gaap_ProductOrServiceAxis=ions_IONISDMPK25Member
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