No definition available.

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- Definition

Cumulative payments received since inception of the collaboration agreement included in the transaction price for the performance obligation.

+ References

No definition available.

+ Details

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- Definition

Cumulative amount of payments received under the collaboration agreement as of the end of the reporting period.

+ References

No definition available.

+ Details

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Data Type:	xbrli:monetaryItemType
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- Definition

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

+ References

No definition available.

+ Details

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Data Type:	xbrli:monetaryItemType
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- Definition

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

+ References

No definition available.

+ Details

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Data Type:	xbrli:monetaryItemType
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- Definition

The minimum amount of payments receivable for license fees and substantive milestones under the collaboration agreement.

+ References

No definition available.

+ Details

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- Definition

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

+ References

No definition available.

+ Details

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Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	instant

- Definition

The number of license fees earned during the period under the collaboration agreement.

+ References

No definition available.

+ Details

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Data Type:	xbrli:integerItemType
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- Definition

The number of drugs that have been licensed under the collaboration agreement.

+ References

No definition available.

+ Details

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Data Type:	xbrli:integerItemType
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- Definition

The number of performance obligations completed under the collaboration agreement.

+ References

No definition available.

+ Details

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Namespace Prefix:	ions_
Data Type:	xbrli:integerItemType
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- Definition

The number of programs advanced under the collaboration agreement.

+ References

No definition available.

+ Details

Name:	ions_NumberOfProgramsAdvanced
Namespace Prefix:	ions_
Data Type:	xbrli:integerItemType
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Period Type:	duration

- Definition

The number of separate performance obligations under the collaboration agreement.

+ References

No definition available.

+ Details

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Data Type:	xbrli:integerItemType
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- Definition

The amount of consideration the Company earned or is eligible to earn under the collaboration agreement, including any variable consideration.

+ References

No definition available.

+ Details

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Namespace Prefix:	ions_
Data Type:	xbrli:monetaryItemType
Balance Type:	credit
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- Definition

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

+ References

No definition available.

+ Details

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Namespace Prefix:	ions_
Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	duration

- 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

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- Definition

Amount of obligation to transfer good or service to customer for which consideration has been received or is receivable.

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
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- Definition

Amount, excluding tax collected from customer, of revenue from satisfaction of performance obligation by transferring promised good or service to customer. Tax collected from customer is tax assessed by governmental authority that is both imposed on and concurrent with specific revenue-producing transaction, including, but not limited to, sales, use, value added and excise.

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
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Collaborative Arrangements and Licensing Agreements, AstraZeneca (Details) $ in Thousands	1 Months Ended		3 Months Ended				12 Months Ended
	Jul. 31, 2015 USD ($) PerformanceObligation	Dec. 31, 2012 USD ($) PerformanceObligation	Dec. 31, 2019 USD ($) Drug	Dec. 31, 2018 USD ($) Program	Sep. 30, 2018 USD ($)	Mar. 31, 2018 USD ($) LicenseFee	Dec. 31, 2019 USD ($) Drug	Dec. 31, 2018 USD ($)	Dec. 31, 2017 USD ($)	Mar. 31, 2014 PerformanceObligation
Collaborative Arrangement and Licensing Agreement [Abstract]
Revenue							$ 1,122,599	$ 599,674	$ 514,179
R&D Revenue [Member]
Collaborative Arrangement and Licensing Agreement [Abstract]
Revenue							770,149	344,752	$ 394,165
AstraZeneca [Member]
Collaborative Arrangement and Licensing Agreement [Abstract]
Deferred revenue			$ 25,000	$ 40,100			$ 25,000	$ 40,100
AstraZeneca [Member] \| Revenue [Member] \| Strategic Partner [Member]
Collaborative Arrangement and Licensing Agreement [Abstract]
Concentration percentage							3.00%	20.00%	4.00%
AstraZeneca [Member] \| R&D Revenue [Member]
Collaborative Arrangement and Licensing Agreement [Abstract]
Revenue							$ 28,100	$ 120,700	$ 21,600
Cardiovascular, Renal and Metabolic Diseases [Member]
Collaborative Arrangement and Licensing Agreement [Abstract]
Number of licensed drugs \| Drug			3				3
Upfront payment received	$ 65,000
Minimum amount of payments receivable for license fees and milestones			$ 4,000,000				$ 4,000,000
Maximum amount of payments receivable for development milestones			1,100,000				1,100,000
Maximum amount of payments receivable for regulatory milestones			2,900,000				2,900,000
Next prospective payment			10,000				10,000
Cumulative payments received			175,000				175,000
Number of separate performance obligations \| PerformanceObligation	1
Transaction price	$ 65,000
Number of license fees earned \| LicenseFee						2
Revenue				$ 10,000	$ 10,000
Cardiovascular, Renal and Metabolic Diseases [Member] \| ION532 [Member]
Collaborative Arrangement and Licensing Agreement [Abstract]
Revenue						$ 30,000
Cardiovascular, Renal and Metabolic Diseases [Member] \| IOIN839 [Member]
Collaborative Arrangement and Licensing Agreement [Abstract]
Revenue						$ 30,000
Cardiovascular, Renal and Metabolic Diseases [Member] \| R&D Revenue [Member]
Collaborative Arrangement and Licensing Agreement [Abstract]
Cumulative payments included in transaction price for performance obligation			90,000				90,000
Oncology [Member]
Collaborative Arrangement and Licensing Agreement [Abstract]
Upfront payment received		$ 31,000	10,000
Minimum amount of payments receivable for license fees and milestones			450,000				450,000
Maximum amount of payments receivable for development milestones			152,000				152,000
Maximum amount of payments receivable for regulatory milestones			275,000				275,000
Cumulative payments received			125,000				125,000
Number of separate performance obligations \| PerformanceObligation		4
Number of performance obligations completed \| PerformanceObligation										3
Number of programs advanced \| Program				2
Revenue				$ 30,000
Oncology [Member] \| Maximum [Member]
Collaborative Arrangement and Licensing Agreement [Abstract]
Next prospective payment			$ 25,000				$ 25,000
Oncology [Member] \| Danvatirsen [Member]
Collaborative Arrangement and Licensing Agreement [Abstract]
Revenue				17,500
Oncology [Member] \| ION736 [Member]
Collaborative Arrangement and Licensing Agreement [Abstract]
Revenue				$ 10,000