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Debt instrument conversion obligation number of consecutive business days after consecutive trading day period.

No definition available.

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Debt instrument conversion obligation period of consecutive trading days.

No definition available.

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Debt instrument conversion share amount description.

No definition available.

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Debt instrument conversion value description.

No definition available.

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The percentage of excess of the price paid for the convertible note over the closing stock price on the closing date of the convertible note.

No definition available.

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The carrying amount of the liability component of a convertible note.

No definition available.

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Debt instrument convertible trading days during observation period.

No definition available.

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Debt instrument events of default percentage of principal and accrued and unpaid interest due and payable upon default.

No definition available.

Name:	nbix_DebtInstrumentEventsOfDefaultPercentageOfPrincipalAndAccruedAndUnpaidInterestDueAndPayableUponDefault
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Debt instrument fair value percentage of principal.

No definition available.

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The minimum percentage of the product of the common stock trading price multiplied by the conversion rate during the measurement period as compared to the principal note amount that triggers a conversion option on the notes, if it falls below this percentage.

No definition available.

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Principal amount on conversion rate.

No definition available.

Name:	nbix_PrincipalAmountOnConversionRate
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The number of shares issued in exchange for the original debt being converted in a noncash (or part noncash) transaction. "Part noncash" refers to that portion of the transaction not resulting in cash receipts or payments in the period.

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The rate of interest that was being paid on the original debt issue that is being converted in the noncash (or part noncash) transaction. "Part noncash" refers to that portion of the transaction not resulting in cash receipts or cash payments in the period.

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The carrying amount of the equity component of convertible debt which may be settled in cash upon conversion.

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The price per share of the conversion feature embedded in the debt instrument.

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Ratio applied to the conversion of debt instrument into equity with equity shares divided by debt principal amount.

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Latest date when the debt instrument can be converted into equity, in CCYY-MM-DD format.

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Threshold period of specified consecutive trading days within which common stock price to conversion price of convertible debt instrument must exceed threshold percentage for specified number of trading days to trigger conversion feature.

No definition available.

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Minimum percentage of common stock price to conversion price of convertible debt instruments to determine eligibility of conversion.

No definition available.

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Threshold number of specified trading days that common stock price to conversion price of convertible debt instruments must exceed threshold percentage within a specified consecutive trading period to trigger conversion feature.

No definition available.

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Face (par) amount of debt instrument at time of issuance.

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The average effective interest rate during the reporting period.

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Contractual interest rate for funds borrowed, under the debt agreement.

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Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table.

No definition available.

Name:	us-gaap_DebtInstrumentLineItems
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Percentage of principal amount of debt redeemed.

No definition available.

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Data Type:	num:percentItemType
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Period Type:	duration

Period of time between issuance and maturity of debt instrument, in PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days.

No definition available.

Name:	us-gaap_DebtInstrumentTerm
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Amount, before accumulated amortization, of debt issuance costs. Includes, but is not limited to, legal, accounting, underwriting, printing, and registration costs.

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The cash inflow from the issuance of a long-term debt instrument which can be exchanged for a specified amount of another security, typically the entity's common stock, at the option of the issuer or the holder.

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Price of a single share of a number of saleable stocks of a company.

No definition available.