No definition available.

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- Definition

Represents the maximum amount of payments receivable under the agreement.

+ References

No definition available.

+ Details

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- Definition

Represents the next potential milestone payment to be earned.

+ References

No definition available.

+ Details

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

- Definition

Represents the number of Phase 3 studies in which the drug is being evaluated.

+ References

No definition available.

+ Details

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- Definition

Represents the amount of upfront fees received during the period in the form of equity securities.

+ References

No definition available.

+ Details

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Data Type:	xbrli:monetaryItemType
Balance Type:	credit
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- 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

+ Details

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Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	duration

- Details

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- Details

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- Details

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- Details

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- Details

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- Details

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- Details

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- Details

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Collaborative Arrangements and Licensing Agreements, Satellite Company Collaborations - OncoGenex Technologies Inc. (Details)	1 Months Ended	3 Months Ended								12 Months Ended
	Aug. 31, 2003 USD ($)	Dec. 31, 2015 USD ($)	Sep. 30, 2015 USD ($)	Jun. 30, 2015 USD ($)	Mar. 31, 2015 USD ($)	Dec. 31, 2014 USD ($)	Sep. 30, 2014 USD ($)	Jun. 30, 2014 USD ($)	Mar. 31, 2014 USD ($)	Dec. 31, 2015 USD ($) Study	Dec. 31, 2014 USD ($)	Dec. 31, 2013 USD ($)
Collaborative Arrangement and Licensing Agreement [Abstract]
Revenue earned		$ 51,571,000	$ 49,121,000	$ 120,428,000	$ 62,583,000	$ 84,861,000	$ 44,063,000	$ 57,076,000	$ 28,161,000	$ 283,703,000	$ 214,161,000	$ 147,285,000
OncoGenex Technologies Inc. [Member] \| Satellite Company Collaborative Arrangement and Licensing Agreement [Member]
Collaborative Arrangement and Licensing Agreement [Abstract]
Revenue earned										$ 0	$ 0	$ 0
OncoGenex Technologies Inc. [Member] \| Satellite Company Collaborative Arrangement and Licensing Agreement [Member] \| Custirsen [Member]
Collaborative Arrangement and Licensing Agreement [Abstract]
Number of Phase 3 studies in which drug is being evaluated \| Study										2
OncoGenex Technologies Inc. [Member] \| Satellite Company Collaborative Arrangement and Licensing Agreement [Member] \| OGX-225 [Member]
Collaborative Arrangement and Licensing Agreement [Abstract]
Upfront fee in the form of equity securities	$ 800,000
OncoGenex Technologies Inc. [Member] \| Satellite Company Collaborative Arrangement and Licensing Agreement [Member] \| OGX-225 [Member] \| Phase 2 Study [Member]
Collaborative Arrangement and Licensing Agreement [Abstract]
Next potential milestone		500,000								$ 500,000
OncoGenex Technologies Inc. [Member] \| Satellite Company Collaborative Arrangement and Licensing Agreement [Member] \| OGX-225 [Member] \| Development and Regulatory Milestones [Member]
Collaborative Arrangement and Licensing Agreement [Abstract]
Maximum amount of payments receivable		3,500,000								3,500,000
OncoGenex Technologies Inc. [Member] \| Satellite Company Collaborative Arrangement and Licensing Agreement [Member] \| OGX-225 [Member] \| Development Milestones [Member]
Collaborative Arrangement and Licensing Agreement [Abstract]
Maximum amount of payments receivable		1,500,000								1,500,000
OncoGenex Technologies Inc. [Member] \| Satellite Company Collaborative Arrangement and Licensing Agreement [Member] \| OGX-225 [Member] \| Regulatory Milestones [Member]
Collaborative Arrangement and Licensing Agreement [Abstract]
Maximum amount of payments receivable		2,000,000								2,000,000
OncoGenex Technologies Inc. [Member] \| Satellite Company Collaborative Arrangement and Licensing Agreement [Member] \| Apatorsen [Member]
Collaborative Arrangement and Licensing Agreement [Abstract]
Maximum amount of payments receivable		5,800,000								5,800,000
OncoGenex Technologies Inc. [Member] \| Satellite Company Collaborative Arrangement and Licensing Agreement [Member] \| Apatorsen [Member] \| Phase 3 Study [Member]
Collaborative Arrangement and Licensing Agreement [Abstract]
Next potential milestone		1,300,000								1,300,000
OncoGenex Technologies Inc. [Member] \| Satellite Company Collaborative Arrangement and Licensing Agreement [Member] \| Apatorsen [Member] \| Development Milestones [Member]
Collaborative Arrangement and Licensing Agreement [Abstract]
Maximum amount of payments receivable		1,300,000								1,300,000
OncoGenex Technologies Inc. [Member] \| Satellite Company Collaborative Arrangement and Licensing Agreement [Member] \| Apatorsen [Member] \| Regulatory Milestones [Member]
Collaborative Arrangement and Licensing Agreement [Abstract]
Maximum amount of payments receivable		$ 4,500,000								$ 4,500,000