XML 73 R53.htm IDEA: XBRL DOCUMENT
v3.8.0.1

BIAL Agreement - Additional Information (Detail) - USD ($) $ in Millions | 3 Months Ended | 12 Months Ended
--- | --- | ---
Mar. 31, 2017 | Dec. 31, 2017
License Agreement [Line Items] |  |
Milestone payables |  | $ 132
B I A L |  |
License Agreement [Line Items] |  |
License agreement date |  | Feb. 09, 2017
Up-front license fees | $ (30) |
B I A L | Regulatory Approval and Net Sales Milestones |  |
License Agreement [Line Items] |  |
Milestone payables | 115 |
B I A L | Regulatory and Clinical Results and FDA Acceptance Milestones |  |
License Agreement [Line Items] |  |
Milestone payables | $ 20 |

X
- Definition Up front payments received (paid) under collaborative agreements for sponsored research and development, and licensing fees + References No definition available. + Details
Name: | nbix_CollaborativeArrangementUpfrontPaymentReceivedPaid
Namespace Prefix: | nbix_
Data Type: | xbrli:monetaryItemType
Balance Type: | credit
Period Type: | duration

X
- Definition Date of the license agreement, in CCYY-MM-DD format. + References No definition available. + Details
Name: | nbix_LicenseAgreementDate
Namespace Prefix: | nbix_
Data Type: | xbrli:dateItemType
Balance Type: | na
Period Type: | duration

X
- Definition Line items represent financial concepts included in a table. These concepts are used to disclose the terms and amounts of a license agreement. + References No definition available. + Details
Name: | nbix_LicenseAgreementLineItems
Namespace Prefix: | nbix_
Data Type: | xbrli:stringItemType
Balance Type: | na
Period Type: | duration

X
- Definition The amount of potential milestone payments to be paid under a license agreement. + References No definition available. + Details
Name: | nbix_PotentialMilestonePayments
Namespace Prefix: | nbix_
Data Type: | xbrli:monetaryItemType
Balance Type: | credit
Period Type: | instant

X
- Details
Name: | us-gaap_RelatedPartyTransactionsByRelatedPartyAxis=nbix_BIALMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

X
- Details
Name: | us-gaap_ResearchAndDevelopmentArrangementContractToPerformForOthersByTypeAxis=nbix_RegulatoryApprovalAndNetSalesMilestonesMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

X
- Details
Name: | us-gaap_ResearchAndDevelopmentArrangementContractToPerformForOthersByTypeAxis=nbix_RegulatoryApprovalClinicalResultsAndFdaAcceptanceMilestonesMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |