No definition available.

Name:	ions_CollaborativeArrangementAndLicensingAgreementAbstract
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- Definition

The ownership percentage represented by the entity's equity investments in companies with which it conducts business and which are not accounted for under the equity method of accounting.

+ References

No definition available.

+ Details

Name:	ions_EquityInvestmentsOtherThanEquityMethodOwnershipPercentage
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Data Type:	num:percentItemType
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Period Type:	instant

- Definition

The maximum amount of payments receivable under the collaboration agreement.

+ References

No definition available.

+ Details

Name:	ions_MaximumAmountOfPaymentsReceivable
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Data Type:	xbrli:monetaryItemType
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Period Type:	instant

- Definition

The maximum amount of payments receivable for commercialization milestones under the collaboration agreement.

+ References

No definition available.

+ Details

Name:	ions_MaximumAmountOfPaymentsReceivableForCommercializationMilestones
Namespace Prefix:	ions_
Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	instant

- Definition

The next potential payment to be earned under the collaboration agreement.

+ References

No definition available.

+ Details

Name:	ions_NextPotentialPayment
Namespace Prefix:	ions_
Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	instant

- Definition

Percentage of non-royalty cash payments received from agreement with collaboration partner to be paid to another collaboration partner.

+ References

No definition available.

+ Details

Name:	ions_PercentageOfNonRoyaltyCashPaymentsReceivedUnderCollaborationAgreementToBePaidToCollaborationPartner
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Period Type:	duration

- Definition

Percentage of sales paid as a royalty to a collaboration partner under the collaboration agreement.

+ References

No definition available.

+ Details

Name:	ions_RoyaltyPercentage
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Data Type:	num:percentItemType
Balance Type:	na
Period Type:	duration

- Definition

The total amount of upfront payments received or expected to be received in the near-term under the collaboration agreement.

+ References

No definition available.

+ Details

Name:	ions_UpfrontPayment
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Data Type:	xbrli:monetaryItemType
Balance Type:	credit
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- Definition

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.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 275
-SubTopic 10
-Section 50
-Paragraph 18
-URI http://asc.fasb.org/extlink&oid=51801978&loc=d3e6351-108592

Reference 2: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 825
-SubTopic 10
-Section 50
-Paragraph 20
-URI http://asc.fasb.org/extlink&oid=49121117&loc=d3e13531-108611

Reference 3: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 275
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-Section 50
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-URI http://asc.fasb.org/extlink&oid=51801978&loc=d3e6404-108592

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-Name Accounting Standards Codification
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-SubTopic 10
-Section 50
-Paragraph 21
-Subparagraph (a)
-URI http://asc.fasb.org/extlink&oid=49121117&loc=d3e13537-108611

+ Details

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Balance Type:	na
Period Type:	duration

- Definition

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).

+ References

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=26872669&loc=d3e20235-122688

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Balance Type:	credit
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Collaborative Arrangements and Licensing Agreements, Research, Development and Commercialization Partners - Kastle Therapeutics (Details) - USD ($) $ in Thousands	3 Months Ended		6 Months Ended
	Jun. 30, 2016	Jun. 30, 2015	Jun. 30, 2016	Jun. 30, 2015	May 31, 2016
Collaborative Arrangement and Licensing Agreement [Abstract]
Revenue earned	$ 38,470	$ 120,428	$ 75,345	$ 183,012
Kynamro [Member]
Collaborative Arrangement and Licensing Agreement [Abstract]
Maximum amount of payments receivable	95,000		95,000
Upfront payment					$ 15,000
Next potential payment	10,000		10,000
Maximum amount of payments receivable for commercialization milestones	$ 70,000		$ 70,000
Ownership interest percentage	10.00%		10.00%
Royalty percentage on sales earned by Sanofi Genzyme			3.00%
Percentage of non-royalty cash payments received from Kastle earned by Sanofi Genzyme			3.00%
Revenue earned	$ 15,000		$ 15,000
Kynamro [Member] \| Revenue [Member] \| Strategic Partner [Member]
Collaborative Arrangement and Licensing Agreement [Abstract]
Concentration percentage	39.00%		20.00%