XML 55 R37.htm IDEA: XBRL DOCUMENT
v3.19.3.a.u2

Organization and Significant Accounting Policies, Noncontrolling Interest in Akcea Therapeutics, Inc. (Details) - shares shares in Millions | 3 Months Ended |
--- | --- | ---
Dec. 31, 2019 | Mar. 31, 2019 | Jun. 30, 2017
Noncontrolling Interest in Akcea Therapeutics, Inc. [Abstract] |  |  |
Additional shares of Akcea stock received for license of drug | 6.9 | 2.8 |
Akcea [Member] |  |  |
Noncontrolling Interest in Akcea Therapeutics, Inc. [Abstract] |  |  |
Percentage ownership | 76.00% |  | 100.00%
Akcea [Member] | Minimum [Member] |  |  |
Noncontrolling Interest in Akcea Therapeutics, Inc. [Abstract] |  |  |
Percentage ownership | 68.00% |  |
Akcea [Member] | Maximum [Member] |  |  |
Noncontrolling Interest in Akcea Therapeutics, Inc. [Abstract] |  |  |
Percentage ownership | 77.00% |  |

X
- Definition The number of additional shares of stock received from Akcea Therapeutics, Inc. as a sublicense fee in connection with Pfizer licensing AKCEA-ANGPTL3-L. + References No definition available. + Details
Name: | ions_SharesReceivedFromSubsidiaryForLicenseOfDrug
Namespace Prefix: | ions_
Data Type: | xbrli:sharesItemType
Balance Type: | na
Period Type: | duration

X
- Definition The parent entity's interest in net assets of the subsidiary, expressed as a percentage. + References No definition available. + Details
Name: | us-gaap_MinorityInterestOwnershipPercentageByParent
Namespace Prefix: | us-gaap_
Data Type: | num:percentItemType
Balance Type: | na
Period Type: | instant

X
- References No definition available. + Details
Name: | us-gaap_ProceedsFromIssuanceOrSaleOfEquityAbstract
Namespace Prefix: | us-gaap_
Data Type: | xbrli:stringItemType
Balance Type: | na
Period Type: | duration

X
- Details
Name: | srt_OwnershipAxis=ions_AkceaTherapeuticsIncMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

X
- Details
Name: | srt_RangeAxis=srt_MinimumMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

X
- Details
Name: | srt_RangeAxis=srt_MaximumMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |