0001564590-20-021952 | 10-Q | XBRL Viewer | Neurocrine Biosciences INC

Restricted Cash - Summary of Reconciliation of Cash, Cash Equivalents, and Restricted Cash (Detail) - USD ($) $ in Millions	Mar. 31, 2020	Dec. 31, 2019
Restricted Cash And Cash Equivalents [Abstract]
Cash and cash equivalents	$ 187.0	$ 112.3
Restricted cash	3.2	3.2
Total cash, cash equivalents and restricted cash	$ 190.2	$ 115.5

Condensed Consolidated Balance Sheets - USD ($) $ in Millions	Mar. 31, 2020	Dec. 31, 2019
Current assets:
Cash and cash equivalents	$ 187.0	$ 112.3
Debt securities available-for-sale, at fair value (amortized cost $584.1 million at March 31, 2020 and $557.3 million at December 31, 2019)	584.7	558.2
Accounts receivable	148.6	126.6
Inventories	21.2	17.3
Other current assets	26.7	16.6
Total current assets	968.2	831.0
Debt securities available-for-sale, at fair value (amortized cost $237.8 million at March 31, 2020 and $299.3 million at December 31, 2019)	235.9	299.7
Right-of-use assets	73.3	74.3
Equity securities	39.4	55.9
Property and equipment, net	41.9	41.9
Restricted cash	3.2	3.2
Total assets	1,361.9	1,306.0
Current liabilities:
Accounts payable and accrued liabilities	125.9	141.3
Convertible senior notes		408.8
Other current liabilities	14.4	15.2
Total current liabilities	140.3	565.3
Convertible senior notes	414.1	408.8
Operating lease liabilities	85.6	86.7
Other long-term liabilities	21.6	17.1
Total liabilities	661.6	669.1
Stockholders’ equity:
Preferred stock, $0.001 par value; 5.0 shares authorized; no shares issued and outstanding at March 31, 2020 and December 31, 2019
Common stock, $0.001 par value; 220.0 shares authorized; issued and outstanding shares were 92.8 at March 31, 2020 and 92.3 at December 31, 2019	0.1	0.1
Additional paid-in capital	1,796.9	1,768.1
Accumulated other comprehensive (loss) income	(1.4)	1.4
Accumulated deficit	(1,095.3)	(1,132.7)
Total stockholders’ equity	700.3	636.9
Total liabilities and stockholders’ equity	$ 1,361.9	$ 1,306.0

Condensed Consolidated Statements of Cash Flows - USD ($) $ in Millions	3 Months Ended
	Mar. 31, 2020	Mar. 31, 2019
Cash Flows from Operating Activities:
Net income (loss)	$ 37.4	$ (102.1)
Reconciliation of net income (loss) to net cash provided by (used in) operating activities:
Share-based compensation expense	22.8	15.8
Depreciation	2.1	1.6
Amortization of debt discount	5.0	4.6
Amortization of debt issuance costs	0.3	0.3
Change in fair value of equity security investments	16.5	(1.7)
Other	0.4	(0.2)
Change in operating assets and liabilities:
Accounts receivable	(22.1)	(15.7)
Inventory	(3.9)	(1.8)
Accounts payable and accrued liabilities	(16.2)	(16.6)
Other current assets and liabilities, net	(4.1)	3.3
Net cash provided by (used in) operating activities	38.2	(112.5)
Cash Flows from Investing Activities:
Purchases of debt securities available-for-sale	(172.0)	(116.3)
Sales and maturities of debt securities available-for-sale	206.5	215.9
Purchases of equity securities		(54.7)
Purchases of property and equipment	(1.3)	(3.9)
Net cash provided by investing activities	33.2	41.0
Cash Flows from Financing Activities:
Issuance of common stock	3.3	2.6
Net cash provided by financing activities	3.3	2.6
Change in cash and cash equivalents and restricted cash	74.7	(68.9)
Cash and cash equivalents and restricted cash at beginning of period	115.5	147.2
Cash and cash equivalents and restricted cash at end of period	190.2	78.3
Supplemental Disclosure:
Non-cash capital expenditures	$ 0.8	$ 0.6

Significant Collaboration and Licensing Agreements

3 Months Ended

Mar. 31, 2020

Text Block [Abstract]

Significant Collaboration and Licensing Agreements

2. Significant Collaboration and Licensing Agreements

AbbVie. In June 2010, we entered into an exclusive worldwide collaboration with AbbVie to develop and commercialize elagolix and all next-generation gonadotropin-releasing factor antagonists for women’s and men’s health. In connection with the agreement, AbbVie made an upfront payment of $75.0 million and agreed to make additional development and regulatory event-based milestone payments of up to $480.0 million, of which $135.0 million has been earned, and up to an additional $50.0 million in commercial event-based milestone payments.

Under the terms of the agreement, AbbVie is responsible for all third-party development, marketing, and commercialization costs. We will be entitled to a percentage of worldwide sales of GnRH Compounds for the longer of ten years or the life of the related patent rights. AbbVie may terminate the collaboration at its discretion upon 180 days’ written notice to us.

We evaluated the terms of this agreement under Topic 606, Revenue from Contracts with Customers, and determined that there is one performance obligation, the exclusive worldwide license with rights to develop, manufacture, and commercialize elagolix. At execution, the transaction price included only the $75.0 million up-front consideration received. None of the development or regulatory milestones were included in the transaction price, as all milestone amounts were fully constrained. As part of our evaluation of the constraint, we considered numerous factors, including that achievement of the milestones is outside of our control and contingent upon success in future clinical trials and the licensee’s efforts. Any consideration related to sales-based milestones (including royalties) will be recognized when the related sales occur as they were determined to relate predominantly to the license granted to AbbVie and therefore have also been excluded from the transaction price. We will re-evaluate the transaction price in each reporting period and as uncertain events are resolved or other changes in circumstances occur.

BIAL – Portela & Ca, S.A. In the first quarter of 2017, we entered into an exclusive license agreement with BIAL – Portela & Ca, S.A., or BIAL, for the development and commercialization of ONGENTYS for the treatment of human diseases and conditions, including Parkinson’s disease, in the US and Canada. In connection with the agreement, we paid BIAL an upfront license fee of $30.0 million and agreed to make additional regulatory event-based milestone payments of up to $40.0 million, of which $20.0 million has been paid, and up to an additional $75.0 million in commercial event-based milestone payments.

In April 2020, we received FDA approval for ONGENTYS as an adjunctive therapy to levodopa/DOPA decarboxylase inhibitors in adult Parkinson's disease patients. FDA approval of ONGENTYS for Parkinson’s disease triggered a milestone payment of $20.0 million.

Under the terms of the agreement, we are responsible for the commercialization of ONGENTYS in the US and Canada. Further, we will rely on BIAL for the commercial supply of ONGENTYS. Upon our written request prior to the estimated expiration of the term of a licensed product, the parties shall negotiate a good faith continuation of BIAL’s supply of such licensed product after the term. After the term, and if BIAL is not supplying a certain licensed product, we shall pay BIAL a trademark royalty based on the net sales of such licensed product.

Upon commercialization of ONGENTYS, we will determine certain annual sales forecasts. In the event we fail to meet the minimum sales requirements for a particular year, we would be obligated to pay BIAL an amount equal to the difference between the actual net sales and minimum sales requirements for such year.

Unless earlier terminated, the agreement will continue on a licensed product-by-product and country-by-country basis until a generic product in respect of such licensed product under the agreement is sold in a country and sales of such generic product are greater than a specified percentage of total sales of such licensed product in such country.

Either party may terminate the agreement if the other party materially breaches the agreement and does not cure the breach within a specified notice period, or upon the other party’s insolvency. BIAL may terminate the agreement if we fail to use commercially reasonable efforts to submit an NDA for a licensed product by a specified date, in the event we fail to meet the minimum sales requirements for any two years, or under certain circumstances involving a change of control of Neurocrine Biosciences. Under certain circumstances where BIAL elects to terminate the agreement in connection with a change of control of Neurocrine Biosciences, BIAL would be obligated to pay us a termination fee. We may terminate the agreement at any time for any reason upon nine months’ written notice to BIAL.

Voyager. In the first quarter of 2019, we entered into a collaboration and license agreement with Voyager, a clinical-stage gene therapy company. The agreement is focused on the development and commercialization of four programs using Voyager’s proprietary gene therapy platform. The four programs consist of the NBIb-1817 program for Parkinson’s disease, the Friedreich’s ataxia program and the rights to two undisclosed programs.

In connection with the agreement, we paid Voyager $115.0 million upfront and purchased $50.0 million of Voyager’s common stock at $11.9625 per share, representing approximately 4.2 million shares. Pursuant to the terms of the agreement, Voyager may also be entitled to an additional $1.7 billion in development, regulatory, and commercial milestone payments, as well as royalties on net sales of any collaboration product. We accounted for the transaction as an asset acquisition as the set of acquired assets did not constitute a business. Our equity investment in Voyager was recorded at a fair value of $54.7 million after considering Voyager’s stock price on the date of closing and certain lock-up and voting provisions applicable to the acquired shares. The remaining $113.1 million of the purchase price, which includes the applicable transaction costs, was expensed as in-process research and development, or IPR&D, in the first quarter of 2019.

In June 2019, we entered into an amendment to the collaboration and license agreement with Voyager. Under the terms of the amendment, we paid Voyager $5.0 million upfront to obtain rights outside the US to the Friedreich’s ataxia program in connection with the early return of those rights to Voyager pursuant to a restructuring of Voyager’s gene therapy relationship with Sanofi Genzyme. The upfront payment was expensed as IPR&D in the second quarter of 2019.

Pursuant to development plans agreed to by us and Voyager, unless Voyager exercises its co-development and co-commercialization rights as provided for in the agreement, we will be responsible for all development costs. Further, upon the occurrence of a specified event for each program, we will assume responsibility for the development, manufacturing, and commercialization activities of such program.

We may terminate the collaboration and license agreement with Voyager upon 180 days’ written notice to Voyager prior to the first commercial sale of any collaboration product or upon one year after the date of notice if such notice is provided after the first commercial sale of any collaboration product. Unless terminated earlier, the agreement will continue in effect until the expiration of the last to expire royalty term with respect to any collaboration product or the last expiration or termination of any exercised co-development and co-commercialization rights by Voyager as provided for in the agreement.

Xenon. In December 2019, we entered into a license and collaboration agreement with Xenon Pharmaceuticals Inc., or Xenon, to identify, research, and develop sodium channel inhibitors, including clinical candidate NBI-921352 and three preclinical candidates, which compounds we will have the exclusive right to further develop and commercialize under the terms and conditions set forth in the agreement.

We will be solely responsible, at our sole cost and expense, for all development and manufacturing of the compounds and any pharmaceutical product that contains a compound, subject to Xenon’s right to elect to co-fund the development of one product in a major indication and thus receive a mid-single digit percentage increase in royalties owed on the net sales of such product in the US. If Xenon exercises such option, the parties will share equally all reasonable and documented costs and expenses incurred in connection with the development of such product in the applicable indication, except costs and expenses that are solely related to the development of such product for regulatory approval outside the US.

In connection with the agreement, we paid Xenon $30.0 million upfront and purchased $20.0 million of Xenon’s common stock at $14.196 per share, representing approximately 1.4 million shares. Pursuant to the terms of the agreement, Xenon may also be entitled to an additional $1.7 billion in development, regulatory and commercial milestone payments, as well as royalties on net sales of any collaboration product.

Unless earlier terminated, the term of the license and collaboration agreement will continue on a product-by-product and country-by-country basis until the expiration of the royalty term for such product in such country. Upon the expiration of the royalty term for a particular product and country, the exclusive license granted by Xenon to us with respect to such product and country will become fully paid, royalty free, perpetual, and irrevocable. We may terminate the license and collaboration agreement by providing at least 90 days’ written notice, provided that such unilateral termination will not be effective for certain products until we have used commercially reasonable efforts to complete certain specified clinical studies. Either party may terminate the agreement in the event of a material breach in whole or in part, subject to specified conditions.

Mitsubishi Tanabe Pharma Corporation. In March 2015, we entered into a collaboration and license agreement with Mitsubishi Tanabe Pharma Corporation, or MTPC, for the development and commercialization of INGREZZA for movement disorders in Japan and other select Asian markets. In connection with the agreement, MTPC made an upfront payment of $30.0 million and agreed to make an additional $85.0 million in development and regulatory event-based milestone payments, payments for the manufacture of pharmaceutical products and royalties on product sales in select territories in Asia.

Under the terms of the agreement, MTPC is responsible for all third-party development, marketing, and commercialization costs in Japan and other select Asian markets and we would be entitled to a percentage of sales of INGREZZA in Japan and other select Asian markets for the longer of ten years or the life of the related patent rights. Further, the collaboration effort between the parties to advance INGREZZA towards commercialization in Japan and other select Asian markets is governed by joint steering and development committees with representatives from both parties. There are no performance, cancellation, termination, or refund provisions in the agreement that would have a material financial consequence to us. We do not directly control when event-based payments will be achieved or when royalty payments will begin. MTPC may terminate the agreement at its discretion upon 180 days’ written notice to us. In such event, all INGREZZA product rights for Japan and other select Asian markets would revert to us.

We assessed this arrangement in accordance with Topic 606 and identified the following performance obligations: (i) INGREZZA technology license and existing know-how; and (ii) development activities to initiate a clinical study of INGREZZA for Huntington’s chorea. We have the option to participate on the joint steering committee, but since participation is at our option it was deemed to not be a performance obligation. The option for MTPC to engage us to manufacture and supply pharmaceutical products, not at a discount, was not considered a material right and therefore not a performance obligation. Based on these assessments, we identified the license and the development activities as the only performance obligations at the inception of the agreement, which were both deemed to be distinct.

To evaluate the appropriate transaction price, we determined that the up-front payment received constituted the entirety of the consideration to be included in the transaction price and to be allocated to the performance obligations based on our best estimate of their relative stand-alone selling prices. For the license, the stand-alone selling price was calculated using an income approach model and included the following key assumptions: the development timeline, revenue forecast, discount rate and probabilities of technical and regulatory success. The relative selling price of our development activities to initiate a clinical study of INGREZZA for Huntington’s chorea was based on an assessment of costs to perform the study, based upon a peer company analysis for similar studies. We believe a change in the assumptions used to determine our stand-alone selling price for the license most likely would not have a significant effect on the allocation of consideration received (or receivable) to the performance obligations.

At execution, the transaction price included only the $30.0 million up-front consideration received. None of the development or regulatory milestones have been included in the transaction price, as all milestone amounts were fully constrained. As part of our evaluation of the constraint, we considered numerous factors, including that achievement of the milestones is outside of our control

and contingent upon success in future clinical studies and the licensee’s efforts. Any consideration related to sales-based milestones (including royalties) will be recognized when the related sales occur as they were determined to relate predominantly to the license granted to MTPC and therefore have also been excluded from the transaction price. We will re-evaluate the transaction price in each reporting period and as uncertain events are resolved or other changes in circumstances occur. Under the terms of the agreement, any payment we receive is generally non-refundable.

Since inception of the agreement, we have recognized revenue of $21.9 million associated with the delivery of a technology license and existing know-how and $15.0 million in development event-based payments resulting from MTPC’s initiation of Phase II/III development of INGREZZA in TD in Asia. In the first quarter of 2020, we recognized revenue of $1.3 million in connection with the ongoing KINECT-HD study, a placebo-controlled Phase III study of valbenazine in adult Huntington’s disease patients with chorea. In accordance with our continuing performance obligations, $8.1 million of the $30.0 million upfront payment received is being deferred and will be recognized as revenue over the KINECT-HD study period using an input method according to research and development, or R&D, costs incurred to date relative to estimated total R&D costs.

Convertible Senior Notes

3 Months Ended

Mar. 31, 2020

Debt Disclosure [Abstract]

Convertible Senior Notes

8. Convertible Senior Notes

On May 2, 2017, we completed a private placement of $517.5 million in aggregate principal amount of 2.25% convertible senior notes due 2024 and entered into an indenture agreement, or the 2024 Indenture, with respect to the 2024 Notes. The 2024 Notes accrue interest at a fixed rate of 2.25% per year, payable semiannually in arrears on May 15 and November 15 of each year, beginning on November 15, 2017. The 2024 Notes mature on May 15, 2024. The net proceeds from the issuance of the 2024 Notes were approximately $502.8 million, after deducting commissions and the offering expenses payable by us.

Holders of the 2024 Notes may convert the 2024 Notes at any time prior to the close of business on the business day immediately preceding May 15, 2024, only under the following circumstances:

(i)

during any calendar quarter (and only during such calendar quarter), if the last reported sale price of our common stock for at least 20 trading days (whether or not consecutive) during a period of 30 consecutive trading days ending on the last trading day of the immediately preceding calendar quarter is greater than 130% of the conversion price on each applicable trading day;

(ii)

during the five business-day period immediately after any five consecutive trading-day period (the measurement period) in which the trading price (as defined in the 2024 Indenture) per $1,000 principal amount of the 2024 Notes for each trading day of the measurement period was less than 98% of the product of the last reported sale price of our common stock and the conversion rate on each such trading day;

(iii)

upon the occurrence of specified corporate events, including a merger or a sale of all or substantially all of our assets; or

(iv)

if we call the 2024 Notes for redemption, until the close of business on the business day immediately preceding the redemption date.

On or after January 15, 2024, until the close of business on the scheduled trading day immediately preceding May 15, 2024, holders may convert their 2024 Notes at any time.

Upon conversion, holders will receive the principal amount of their 2024 Notes and any excess conversion value, calculated based on the per share volume-weighted average price for each of the 30 consecutive trading days during the observation period (as more fully described in the 2024 Indenture). For both the principal and excess conversion value, holders may receive cash, shares of our common stock or a combination of cash and shares of our common stock, at our option.

It is our intent and policy to settle conversions through combination settlement, which essentially involves repayment of an amount of cash equal to the “principal portion” and delivery of the “share amount” in excess of the principal portion in shares of common stock or cash. In general, for each $1,000 in principal, the “principal portion” of cash upon settlement is defined as the lesser of $1,000, and the conversion value during the 25-day observation period as described in the 2024 Indenture. The conversion value is the sum of the daily conversion value which is the product of the effective conversion rate divided by 25 days and the daily volume weighted average price, or VWAP, of our common stock. The “share amount” is the cumulative “daily share amount” during the observation period, which is calculated by dividing the daily VWAP into the difference between the daily conversion value (i.e., conversion rate x daily VWAP) and $1,000.

The initial conversion rate for the 2024 Notes is 13.1711 shares of common stock per $1,000 principal amount, which is equivalent to an initial conversion price of approximately $75.92 per share of our common stock. At the initial conversion rate, settlement of the 2024 Notes for shares of our common stock would approximate 6.8 million shares. The conversion rate will be subject to adjustment in some events but will not be adjusted for any accrued and unpaid interest. The initial conversion price of the 2024 Notes represented a premium of approximately 42.5% to the closing sale price of $53.28 per share of our common stock on the Nasdaq Global Select Market on April 26, 2017, the date that we priced the private offering of the 2024 Notes.

In the event of conversion, holders would forgo all future interest payments, any unpaid accrued interest and the possibility of further stock price appreciation. Upon the receipt of conversion requests, the settlement of the 2024 Notes will be paid pursuant to the terms of the 2024 Indenture. In the event that all of the 2024 Notes are converted, we would be required to repay the $517.5 million in principal value and any conversion premium in any combination of cash and shares of our common stock, at our option.

We may not redeem the 2024 Notes prior to May 15, 2021. On or after May 15, 2021, we may redeem for cash all or part of the 2024 Notes if the last reported sale price (as defined in the 2024 Indenture) of our common stock has been at least 130% of the conversion price then in effect for at least 20 trading days (whether or not consecutive) during any 30 consecutive trading-day period ending on, and including, the trading day immediately before the date which we provide notice of redemption. The redemption price will equal the sum of (i) 100% of the principal amount of the 2024 Notes being redeemed, plus (ii) accrued and unpaid interest, including additional interest, if any, to, but excluding, the redemption date. No sinking fund is provided for the 2024 Notes.

If we undergo a fundamental change, as defined in the 2024 Indenture, subject to certain conditions, holders of the 2024 Notes may require us to repurchase for cash all or part of their 2024 Notes at a repurchase price equal to 100% of the principal amount of the 2024 Notes to be repurchased, plus accrued and unpaid interest to, but excluding, the fundamental change repurchase date. In addition, if a ‘‘make-whole fundamental change’’ (as defined in the 2024 Indenture) occurs prior to January 15, 2024, we will, in certain circumstances, increase the conversion rate for a holder who elects to convert its notes in connection with the make-whole fundamental change.

The 2024 Notes are our general unsecured obligations that rank senior in right of payment to all of our indebtedness that is expressly subordinated in right of payment to the 2024 Notes, and equal in right of payment to our unsecured indebtedness.

While the 2024 Notes are currently classified as a long-term liability, the future convertibility and associated balance sheet classification will be monitored at each quarterly reporting date and analyzed dependent upon market prices of our common stock during the prescribed measurement periods. In the event that the holders of the 2024 Notes have the election to convert the 2024 Notes at any time during the prescribed measurement period, the 2024 Notes would then be considered a current obligation and classified as such. We are not aware of any current events or market conditions that would allow holders of the 2024 Notes to convert the 2024 Notes.

We are required to separately account for the liability and equity components of the 2024 Notes as they may be settled entirely or partially in cash upon conversion in a manner that reflects our economic interest cost. The liability component of the instrument was valued in a manner that reflects the market interest rate for a similar nonconvertible instrument at the date of issuance. The initial carrying value of the liability component of $368.3 million was calculated using a 7.5% assumed borrowing rate. The equity component of $149.2 million, representing the conversion option, was determined by deducting the fair value of the liability component from the par value of the 2024 Notes and was recorded in additional paid-in capital on the consolidated balance sheet at the issuance date. That equity component is treated as a discount on the liability component of the 2024 Notes, which is amortized over the seven-year term of the 2024 Notes using the effective interest rate method. The equity component is not re-measured as long as it continues to meet the conditions for equity classification. At March 31, 2020, the remaining period over which the discount on the liability component will be amortized was approximately 4.1 years.

We allocated the total transaction costs of approximately $14.7 million related to the issuance of the 2024 Notes to the liability and equity components of the 2024 Notes based on their relative values. Transaction costs attributable to the liability component are amortized to interest expense over the seven-year term of the 2024 Notes, and transaction costs attributable to the equity component are netted with the equity component in stockholders’ equity.

The 2024 Notes do not contain any financial or operating covenants or any restrictions on the payment of dividends, the issuance of other indebtedness or the issuance or repurchase of securities by us. The 2024 Indenture contains customary events of default with respect to the 2024 Notes, including that upon certain events of default, 100% of the principal and accrued and unpaid interest on the 2024 Notes will automatically become due and payable.

The 2024 Notes, net of discounts and deferred financing costs, consisted of the following:

(in millions)	March 31, 2020			December 31, 2019
Principal	$	517.5		$	517.5
Deferred financing costs		(6.6	)		(6.9	)
Debt discount, net		(96.8	)		(101.8	)
Net carrying amount	$	414.1		$	408.8

The 2024 Notes were recorded at the estimated value of a similar non-convertible instrument on the date of issuance and accretes to the face value of the 2024 Notes over their seven-year term. The fair value of the 2024 Notes, which was estimated utilizing market quotations from an over-the-counter trading market (Level 2), was $677.2 million at March 31, 2020 and $596.8 million at December 31, 2019.

Net Income (Loss) Per Share (Tables)

3 Months Ended

Mar. 31, 2020

Earnings Per Share [Abstract]

Schedule of Net Income Per Share

Net income per share was calculated as follows:

	Three Months Ended March 31,
(in millions, except per share data)	2020		2019
Net income (loss) - basic and diluted	$	37.4	$	(102.1	)
Weighted-average common shares outstanding:
Basic		92.6		91.1
Effect of dilutive securities:
Stock options		2.4		—
Restricted stock		0.5		—
2024 Notes		1.5		—
Diluted		97.0		91.1
Net income per share:
Basic	$	0.40	$	(1.12	)
Diluted	$	0.39	$	(1.12	)

Schedule of Anti-Dilutive Shares Excluded from Diluted Per Share Amounts

Shares which have been excluded from diluted per share amounts because their effect would have been anti-dilutive include the following:

Three Months Ended

March 31,

(in millions)

2020

2019

Stock options, restricted stock units and convertible senior notes

3.3

8.2

Debt Securities (Tables)

3 Months Ended

Mar. 31, 2020

Investments Debt And Equity Securities [Abstract]

Amortized Cost, Gross Unrealized Gains and Losses, Allowance for Credit Losses and Fair Value of Debt Securities Available-For-Sale

The following table summarizes the amortized cost, unrealized gain and loss recognized in accumulated other comprehensive loss, allowance for credit losses, and fair value of debt securities available-for-sale at March 31, 2020, aggregated by major security type and contractual maturity:

(in millions)	Contractual Maturity	Amortized Cost		Unrealized Gain		Unrealized Loss			Allowance for Credit Losses		Fair Value
Commercial paper	Within 1 year	$	129.7	$	0.1	$	(0.1	)	$	—	$	129.7
Corporate debt securities	Within 1 year		323.3		0.3		(0.9	)		—		322.7
Securities of government-sponsored entities	Within 1 year		131.1		1.2		—			—		132.3
blank		$	584.1	$	1.6	$	(1.0	)	$	—	$	584.7
blank
Corporate debt securities	1 to 2 years	$	213.3	$	0.2	$	(2.2	)	$	—	$	211.3
Securities of government-sponsored entities	1 to 2 years		24.5		0.1		—			—		24.6
		$	237.8	$	0.3	$	(2.2	)	$	—	$	235.9

The following table summarizes the amortized cost, unrealized gain and loss recognized in accumulated other comprehensive income, and fair value of debt securities available-for-sale at December 31, 2019, aggregated by major security type and contractual maturity:

(in millions)	Contractual Maturity	Amortized Cost		Unrealized Gain		Unrealized Loss			Fair Value
Commercial paper	Within 1 year	$	144.5	$	—	$	—		$	144.5
Corporate debt securities	Within 1 year		270.5		0.5		—			271.0
Securities of government-sponsored entities	Within 1 year		142.3		0.4		—			142.7
blank		$	557.3	$	0.9	$	—		$	558.2
blank
Corporate debt securities	1 to 2 years	$	250.5	$	0.5	$	(0.1	)	$	250.9
Securities of government-sponsored entities	1 to 2 years		48.8		—		—			48.8
		$	299.3	$	0.5	$	(0.1	)	$	299.7

Gross Unrealized Losses and Fair Value Available-For-Sale Investments in Unrealized Loss Position

The following table summarizes debt securities available-for-sale in an unrealized loss position for which an allowance for credit losses has not been recorded at March 31, 2020, aggregated by major security type and length of time in a continuous unrealized loss position:

	Less Than 12 Months					12 Months or Longer				Total
(in millions)	Fair Value		Unrealized Loss			Fair Value		Unrealized Loss		Fair Value		Unrealized Loss
Commercial paper	$	19.9	$	(0.1	)	$	—	$	—	$	19.9	$	(0.1	)
Corporate debt securities		409.8		(3.1	)		—		—		409.8		(3.1	)
blank	$	429.7	$	(3.2	)	$	—	$	—	$	429.7	$	(3.2	)

The following table summarizes debt securities available-for-sale in an unrealized loss position at December 31, 2019, aggregated by major security type and length of time in a continuous unrealized loss position:

Less Than 12 Months

12 Months or Longer

Total

(in millions)

Fair

Value

Unrealized

Loss

Fair

Value

Unrealized

Loss

Fair

Value

Unrealized

Loss

Corporate debt securities

186.1

(0.1

)

—

186.1

(0.1

)

Leases

3 Months Ended

Mar. 31, 2020

Leases [Abstract]

Leases

7. Leases

At March 31, 2020, our operating leases consisted of the following:

Address	Type	Square Feet		Commencement Date	Expiration Date
12780 El Camino Real ⁽¹⁾	Office/Laboratory		141,000	August 7, 2019	July 31, 2031
12790 El Camino Real, Suite 130 ⁽¹⁾	Office		2,000	December 1, 2019	July 31, 2031
12790 El Camino Real, Suite 150 ⁽¹⁾	Office		8,000	August 7, 2019	July 31, 2031
12790 El Camino Real, Suite 300 ⁽¹⁾	Office		28,000	December 1, 2019	July 31, 2031
12777 High Bluff Drive ⁽²⁾	Office		45,000	July 1, 2018	July 31, 2029
12790 El Camino Real, Suite 200 ⁽¹⁾	Office		28,000	February 1, 2021	July 31, 2031
12790 El Camino Real, Suite 100 ⁽¹⁾	Office		17,000	February 1, 2021	July 31, 2031

_____________________________________

⁽¹⁾ Under the terms of the lease, we have two options to extend the term of the lease for a period of ten years each. We were not reasonably certain to exercise either of these options at lease commencement. As such, neither option was recognized as part of the associated operating lease right-of-use asset or liability. In connection with the lease, in lieu of a cash security deposit, Wells Fargo Bank, N.A., or Well Fargo, issued a $3.0 million letter of credit on our behalf, which is secured by a deposit of equal amount.

⁽²⁾ Under the terms of the lease, we do not have the option to extend the lease. In lieu of a cash security deposit, Wells Fargo issued a $1.0 million letter of credit on our behalf, which is secured by a deposit of $0.2 million.

Our operating lease cost was $2.5 million and $1.9 million for the three months ended March 31, 2020 and 2019, respectively. Cash paid for amounts in the measurement of lease liabilities for operating cash flows from operating leases was $2.1 million and $1.6 million for the three months ended March 31, 2020 and 2019, respectively.

Our operating leases had a weighted average remaining lease term of 11.0 years and 11.4 years at March 31, 2020 and December 31, 2019, respectively, and a weighted average discount rate of 5.8% at March 31, 2020 and December 31, 2019, respectively.

At March 31, 2020, the approximate future minimum lease payments under operating leases were as follows:

(in millions)	Operating Leases
Year Ending December 31,
2020 (9 months remaining)	$	6.5
2021		10.6
2022		10.9
2023		11.2
2024		11.6
Thereafter		79.7
Total operating lease payments		130.5
Less accreted interest		36.1
Total operating lease liabilities		94.4
Less current operating lease liabilities		8.8
Noncurrent operating lease liabilities	$	85.6

_____________________________________

Note: Amounts presented in the table above exclude $28.3 million of non-cancelable future minimum lease payments for operating leases that have not yet commenced.

Leases - Summary of Minimum Lease Payments for Operating Lease Liabilities (Detail) - USD ($) $ in Millions	Mar. 31, 2020	Dec. 31, 2019
Leases [Abstract]
2020 (9 months remaining)	$ 6.5
2021	10.6
2022	10.9
2023	11.2
2024	11.6
Thereafter	79.7
Total operating lease payments	130.5
Less accreted interest	36.1
Operating Lease, Liability	94.4
Less current operating lease liabilities	8.8
Noncurrent operating lease liabilities	$ 85.6	$ 86.7

Convertible Senior Notes - Additional Information (Detail) $ / shares in Units, shares in Millions		3 Months Ended
	May 02, 2017 USD ($) d $ / shares shares	Mar. 31, 2020 USD ($)	Dec. 31, 2019 USD ($)
Debt Instrument [Line Items]
Convertible senior notes principal amount		$ 517,500,000	$ 517,500,000
2.25% Convertible Senior Notes due 2024
Debt Instrument [Line Items]
Convertible senior notes principal amount	$ 517,500,000
Convertible senior notes interest percentage	2.25%
Convertible senior notes convertible latest date	May 15, 2024
Proceeds from Senior Convertible Notes	$ 502,800,000
Threshold common stock trading days \| d	20
Threshold consecutive common stock trading days \| d	30
Threshold percentage of common stock price trigger	130.00%
Debt instrument conversion obligation number of consecutive business days after consecutive trading day period	5 days
Principal amount on conversion rate	$ 1,000
Minimum percentage of common stock price trigger	98.00%
Debt instrument convertible trading days during observation period	30 days
Conversion Observation Period	25 days
Debt instrument conversion value description	The conversion value is the sum of the daily conversion value which is the product of the effective conversion rate divided by 25 days and the daily volume weighted average price, or VWAP, of our common stock.
Debt instrument conversion share amount description	The “share amount” is the cumulative “daily share amount” during the observation period, which is calculated by dividing the daily VWAP into the difference between the daily conversion value (i.e., conversion rate x daily VWAP) and $1,000.
Convertible senior notes convertible in to shares	0.00131711
Convertible senior notes conversion price \| $ / shares	$ 75.92
Market Price of Common stock \| $ / shares	$ 53.28
Convertible senior note premium	42.50%
Shares issued to settle notes at initial conversion rate \| shares	6.8
Convertible senior notes redemption rate	100.00%
Convertible senior note carrying value of the liability component	$ 368,300,000
Convertible senior note assumed borrowing rate	7.50%
Convertible senior note carrying value of the equity component	$ 149,200,000
Convertible senior notes term	7 years
Discount on liability component, remaining amortization period		4 years 1 month 6 days
Transaction cost related to issuance of convertible senior note	$ 14,700,000
Debt instrument events of default percentage of principal and accrued and unpaid interest due and payable upon default	100.00%
Convertible senior notes fair value		$ 677,200,000	$ 596,800,000

Document and Entity Information - shares	3 Months Ended
Document and Entity Information - shares	Mar. 31, 2020	Apr. 30, 2020
Cover [Abstract]
Document Type	10-Q
Amendment Flag	false
Document Period End Date	Mar. 31, 2020
Document Fiscal Year Focus	2020
Document Fiscal Period Focus	Q1
Trading Symbol	NBIX
Entity Registrant Name	NEUROCRINE BIOSCIENCES, INC.
Entity Central Index Key	0000914475
Current Fiscal Year End Date	--12-31
Entity Filer Category	Large Accelerated Filer
Entity Small Business	false
Entity Emerging Growth Company	false
Entity Common Stock, Shares Outstanding		92,865,121
Entity Current Reporting Status	Yes
Title of 12(b) Security	Common Stock, $0.001 par value
Security Exchange Name	NASDAQ
Entity Shell Company	false
Entity File Number	0-22705
Entity Tax Identification Number	33-0525145
Entity Address, Address Line One	12780 El Camino Real
Entity Address, City or Town	San Diego
Entity Address, State or Province	CA
Entity Address, Postal Zip Code	92130
City Area Code	858
Local Phone Number	617-7600
Document Quarterly Report	true
Entity Interactive Data Current	Yes
Document Transition Report	false
Entity Incorporation, State or Country Code	DE

Investments Measured at Fair Value on Recurring Basis (Detail) - USD ($) $ in Millions	Mar. 31, 2020	Dec. 31, 2019
Fair Value Assets And Liabilities Measured On Recurring And Nonrecurring Basis [Line Items]
Fair Value	$ 1,050.2	$ 1,029.3
Level 1 \| Fair Value Measurements Recurring
Fair Value Assets And Liabilities Measured On Recurring And Nonrecurring Basis [Line Items]
Fair value of assets on recurring basis	190.2	115.5
Level 2 \| Fair Value Measurements Recurring
Fair Value Assets And Liabilities Measured On Recurring And Nonrecurring Basis [Line Items]
Fair value of assets on recurring basis	820.6	857.9
Level 3 \| Fair Value Measurements Recurring
Fair Value Assets And Liabilities Measured On Recurring And Nonrecurring Basis [Line Items]
Fair value of assets on recurring basis	39.4	55.9
Cash and money market fund
Fair Value Assets And Liabilities Measured On Recurring And Nonrecurring Basis [Line Items]
Fair Value	187.0	112.3
Cash and money market fund \| Level 1 \| Fair Value Measurements Recurring
Fair Value Assets And Liabilities Measured On Recurring And Nonrecurring Basis [Line Items]
Fair value of assets on recurring basis	187.0	112.3
Total cash and cash equivalents
Fair Value Assets And Liabilities Measured On Recurring And Nonrecurring Basis [Line Items]
Fair Value	187.0	112.3
Total cash and cash equivalents \| Level 1 \| Fair Value Measurements Recurring
Fair Value Assets And Liabilities Measured On Recurring And Nonrecurring Basis [Line Items]
Fair value of assets on recurring basis	187.0	112.3
Certificates of Deposit
Fair Value Assets And Liabilities Measured On Recurring And Nonrecurring Basis [Line Items]
Fair Value	3.2	3.2
Certificates of Deposit \| Level 1 \| Fair Value Measurements Recurring
Fair Value Assets And Liabilities Measured On Recurring And Nonrecurring Basis [Line Items]
Fair value of assets on recurring basis	3.2	3.2
Total restricted cash
Fair Value Assets And Liabilities Measured On Recurring And Nonrecurring Basis [Line Items]
Fair Value	3.2	3.2
Total restricted cash \| Level 1 \| Fair Value Measurements Recurring
Fair Value Assets And Liabilities Measured On Recurring And Nonrecurring Basis [Line Items]
Fair value of assets on recurring basis	3.2	3.2
Commercial paper
Fair Value Assets And Liabilities Measured On Recurring And Nonrecurring Basis [Line Items]
Fair Value	129.7	144.5
Commercial paper \| Level 2 \| Fair Value Measurements Recurring
Fair Value Assets And Liabilities Measured On Recurring And Nonrecurring Basis [Line Items]
Fair value of assets on recurring basis	129.7	144.5
Corporate debt securities
Fair Value Assets And Liabilities Measured On Recurring And Nonrecurring Basis [Line Items]
Fair Value	534.0	521.9
Corporate debt securities \| Level 2 \| Fair Value Measurements Recurring
Fair Value Assets And Liabilities Measured On Recurring And Nonrecurring Basis [Line Items]
Fair value of assets on recurring basis	534.0	521.9
Securities of government-sponsored entities
Fair Value Assets And Liabilities Measured On Recurring And Nonrecurring Basis [Line Items]
Fair Value	156.9	191.5
Securities of government-sponsored entities \| Level 2 \| Fair Value Measurements Recurring
Fair Value Assets And Liabilities Measured On Recurring And Nonrecurring Basis [Line Items]
Fair value of assets on recurring basis	156.9	191.5
Total debt securities available-for-sale
Fair Value Assets And Liabilities Measured On Recurring And Nonrecurring Basis [Line Items]
Fair Value	820.6	857.9
Total debt securities available-for-sale \| Level 2 \| Fair Value Measurements Recurring
Fair Value Assets And Liabilities Measured On Recurring And Nonrecurring Basis [Line Items]
Fair value of assets on recurring basis	820.6	857.9
Equity securities–biotechnology industry
Fair Value Assets And Liabilities Measured On Recurring And Nonrecurring Basis [Line Items]
Fair Value	39.4	55.9
Equity securities–biotechnology industry \| Level 3 \| Fair Value Measurements Recurring
Fair Value Assets And Liabilities Measured On Recurring And Nonrecurring Basis [Line Items]
Fair value of assets on recurring basis	39.4	55.9
Total equity securities
Fair Value Assets And Liabilities Measured On Recurring And Nonrecurring Basis [Line Items]
Fair Value	39.4	55.9
Total equity securities \| Level 3 \| Fair Value Measurements Recurring
Fair Value Assets And Liabilities Measured On Recurring And Nonrecurring Basis [Line Items]
Fair value of assets on recurring basis	$ 39.4	$ 55.9

Condensed Consolidated Balance Sheets (Parenthetical) - USD ($) $ in Millions	Mar. 31, 2020	Dec. 31, 2019
Statement Of Financial Position [Abstract]
Amortized cost, current	$ 584.1	$ 557.3
Amortized cost, noncurrent	$ 237.8	$ 299.3
Preferred stock, par value	$ 0.001	$ 0.001
Preferred stock, shares authorized	5,000,000.0	5,000,000.0
Preferred stock, shares issued	0	0
Preferred stock, shares outstanding	0	0
Common stock, par value	$ 0.001	$ 0.001
Common stock, shares authorized	220,000,000.0	220,000,000.0
Common stock, shares issued	92,800,000	92,300,000
Common stock, shares outstanding	92,800,000	92,300,000

Organization and Significant Accounting Policies

3 Months Ended

Mar. 31, 2020

Accounting Policies [Abstract]

Organization and Significant Accounting Policies

1. Organization and Significant Accounting Policies

Description of Business. Neurocrine Biosciences, Inc., or Neurocrine Biosciences, the Company, we, our or us, was incorporated in California in 1992 and reincorporated in Delaware in 1996. Neurocrine Continental, Inc., is a Delaware corporation and a wholly owned subsidiary of Neurocrine Biosciences. We also have two wholly owned Irish subsidiaries, Neurocrine Therapeutics, Ltd. and Neurocrine Europe, Ltd. both of which were formed in December 2014 and are inactive.

We are a commercial-stage biopharmaceutical company focused on discovering and developing innovative and life-changing treatments for patients with serious, challenging and under-addressed neurological, endocrine and psychiatric disorders. We specialize in targeting and interrupting disease-causing mechanisms involving the interconnected pathways of the nervous and endocrine systems. Currently, we are primarily focused on the commercialization of INGREZZA^® (valbenazine) in the United States, or US, our first US Food and Drug Administration, or FDA, approved product.

In April 2017, we received FDA approval of our first marketed product, INGREZZA, for the treatment of adults with tardive dyskinesia, or TD. Shortly after receiving FDA approval, we began commercializing INGREZZA in the US using a specialty sales force primarily focused on educating physicians who treat patients with TD, including psychiatrists and neurologists.

In addition to our first marketed product, our collaboration partner, AbbVie Inc., or AbbVie, received approval of ORILISSA^® (elagolix) for the management of moderate to severe endometriosis pain in women from the FDA in July 2018 and Health Canada in October 2018. We receive royalties at tiered percentage rates on any net sales of ORILISSA.

In April 2020, we received FDA approval for ONGENTYS^® (opicapone) as an adjunctive therapy to levodopa/DOPA decarboxylase inhibitors in adult Parkinson's disease patients.

Our late-stage pipeline includes crinecerfont (NBI-74788) for the treatment of congenital adrenal hyperplasia, or CAH, in adult patients, elagolix for the treatment of heavy menstrual bleeding, or HMB, associated with uterine fibroids in women, valbenazine for the treatment of chorea in adult patients with Huntington’s disease, or HD, and NBIb-1817 (VY-AADC) for the treatment of advanced Parkinson’s disease patients with motor fluctuations that are refractory to medical management. Our product candidates for uterine fibroids and advanced Parkinson’s disease are partnered with AbbVie and Voyager Therapeutics, Inc., or Voyager, respectively.

Our early-stage clinical pipeline includes crinecerfont for the treatment of CAH in pediatric patients, elagolix for the treatment of polycystic ovary syndrome, or PCOS, in women, a vesicular monoamine transporter 2, or VMAT2, inhibitor with potential use in the treatment of neurologic and psychiatric disorders and NBI-921352 (XEN901), a clinical-stage candidate with potential in epilepsy. Our product candidate for PCOS is partnered with AbbVie.

In January 2020, we announced a collaboration and optional licensing agreement with Idorsia Pharmaceuticals Ltd, granting us an option to license ACT-709478, a potent, selective, orally active and brain penetrating T-type calcium channel blocker, in clinical development for the treatment of a rare pediatric epilepsy. The option also includes a research collaboration to discover, identify and develop additional novel T-type calcium channel blockers.

Basis of Presentation. The accompanying unaudited condensed consolidated financial statements have been prepared in accordance with accounting principles generally accepted in the United States, or GAAP, for interim financial information and with the instructions of the Securities and Exchange Commission, or SEC, on Form 10-Q and Rule 10-01 of Regulation S-X. Accordingly, they do not include all of the information and disclosures required by GAAP for complete financial statements. In the opinion of management, the condensed consolidated financial statements include all adjustments necessary, which are of a normal and recurring nature, for the fair presentation of our financial position and of the results of operations and cash flows for the periods presented. The accompanying unaudited condensed consolidated financial statements include the accounts of Neurocrine Biosciences and our wholly owned subsidiaries. All significant intercompany balances and transactions have been eliminated in consolidation.

These financial statements should be read in conjunction with the audited consolidated financial statements and notes thereto for the year ended December 31, 2019, included in our Annual Report on Form 10-K, or the 2019 Form 10-K, filed with the SEC. The results of operations for the interim period shown in this report are not necessarily indicative of the results that may be expected for any other interim period or the full year. The condensed consolidated balance sheet at December 31, 2019, has been derived from the audited financial statements as of that date, but does not include all of the information and footnotes required by GAAP for complete financial statements.

There were no significant changes to our significant accounting policies as disclosed in the 2019 Form 10-K, except as set forth below.

Debt Securities. Debt securities consist of investments in certificates of deposit, corporate debt securities, and securities of government-sponsored entities. We classify debt securities as available-for-sale. Debt securities available-for-sale are recorded at fair value, with unrealized gains and losses included in other comprehensive income or loss, net of tax. We exclude accrued interest from both the fair value and amortized cost basis of debt securities. A debt security is placed on nonaccrual status at the time any principal or interest payments become 90 days delinquent. Interest accrued but not received for a debt security placed on nonaccrual status is reversed against interest income.

Interest income includes amortization of purchase premium or discount. Premiums and discounts on debt securities are amortized using the effective interest rate method. Gains and losses on sales of debt securities are recorded on the trade date in investment income and other, net, and determined using the specific identification method.

Allowance for Credit Losses. For debt securities available-for-sale in an unrealized loss position, we first assess whether we intend to sell, or it is more likely than not that we will be required to sell the security before recovery of its amortized cost basis. If either of the criteria regarding intent or requirement to sell is met, the security’s amortized cost basis is written down to fair value through earnings. For debt securities available-for-sale that do not meet the aforementioned criteria, we evaluate whether the decline in fair value has resulted from credit losses or other factors. In making this assessment, we consider the extent to which fair value is less than amortized cost, any changes in interest rates, and any changes to the rating of the security by a rating agency, among other factors. If this assessment indicates that a credit loss exists, the present value of cash flows expected to be collected from the security is compared to the amortized cost basis of the security. If the present value of cash flows expected to be collected is less than the amortized cost basis, a credit loss exists and an allowance for credit losses is recorded, limited by the amount that the fair value is less than the amortized cost basis. Any impairment that has not been recorded through an allowance for credit losses is recognized in other comprehensive income or loss, as applicable.

Accrued interest receivables on debt securities available-for-sale totaled $4.7 million at March 31, 2020. We do not measure an allowance for credit losses for accrued interest receivables. For the purposes of identifying and measuring an impairment, accrued interest is excluded from both the fair value and amortized cost basis of the debt security. Uncollectible accrued interest receivables associated with an impaired debt security are reversed against interest income upon identification of the impairment. No accrued interest receivables were written off during the three months ended March 31, 2020.

Fair Value of Financial Instruments. We record cash equivalents, debt securities available-for-sale and equity securities at fair value based on a fair value hierarchy that distinguishes between assumptions based on market data (observable inputs) and our own assumptions (unobservable inputs). The fair value hierarchy consists of the following three levels:

Level 1 – Quoted prices (unadjusted) in active markets for identical assets or liabilities.

Level 2 – Quoted prices for similar assets or liabilities in active markets, quoted prices for identical or similar assets or liabilities in markets that are not active or inputs that are observable, either directly or indirectly, for substantially the full term of the asset or liability.

Level 3 – Unobservable inputs that reflect our own assumptions about the assumptions that market participants would use in pricing the asset or liability when there is little, if any, market activity for the asset or liability at the measurement date.

Investments in debt securities available-for-sale are classified as Level 2 and carried at fair value. We estimate the fair value of debt securities available-for-sale by utilizing third-party pricing services. These pricing services utilize industry standard valuation models, including both income and market-based approaches, for which all significant inputs are observable, either directly or indirectly, to estimate fair value. Such inputs include market pricing based on real-time trade data for similar instruments, issuer credit spreads, benchmark yields, broker/dealer quotes and other observable inputs. We validate valuations obtained from third-party pricing services by understanding the models used, obtaining market values from other pricing sources, and analyzing data in certain instances.

Investments in equity securities of certain companies that are subject to holding period restrictions longer than one year are classified as Level 3 and carried at fair value using an option pricing valuation model. The most significant assumptions within the option pricing valuation model are the stock price volatility, which is based on the historical volatility of similar companies, and the discount for lack of marketability related to the term of the restrictions.

The carrying amounts of accounts receivable and accounts payable and accrued liabilities approximate their fair values due to their short-term maturities.

Recently Adopted Accounting Pronouncements.

ASU 2016-13. On January 1, 2020, we adopted Accounting Standards Update, or ASU, 2016-13, Financial Instruments – Credit Losses (Topic 326): Measurement of Credit Losses on Financial Instruments, using the modified retrospective transition method. For debt securities available-for-sale, the standard requires an investor to determine whether a decline in the fair value below the amortized cost basis of the investment is due to credit-related factors. Credit-related impairment is recognized as an allowance for credit loss on the balance sheet with a corresponding adjustment to earnings. Credit losses are limited to the amount by which the investment’s amortized cost basis exceeds its fair value and may be subsequently reversed if conditions change. Any impairment that is not credit related is recognized in other comprehensive income or loss, as applicable, net of applicable taxes.

The adoption of ASU 2016-13 did not result in a cumulative-effect adjustment to retained earnings. The comparative prior period information continues to be reported under the accounting standards in effect during those periods.

Recently Issued Accounting Pronouncements.

ASU 2019-12. In December 2019, the FASB issued ASU 2019-12, Income Taxes (Topic 740): Simplifying the Accounting for Income Taxes, which simplifies the accounting for income taxes by removing certain exceptions to the general principles in Topic 740 and amends existing guidance to improve consistent application of Topic 740. ASU 2019-12 is effective for fiscal years beginning after December 15, 2021, and interim periods within those fiscal years, with early adoption permitted in any interim period for which financial statements have not yet been made available for issuance. We are currently evaluating the effect that ASU 2017-12 will have on our condensed consolidated financial statements and related disclosures.

Organization and Significant Accounting Policies (Policies)	3 Months Ended
	Mar. 31, 2020
Accounting Policies [Abstract]
Recently Issued Accounting Pronouncements	Recently Issued Accounting Pronouncements. ASU 2019-12. In December 2019, the FASB issued ASU 2019-12, Income Taxes (Topic 740): Simplifying the Accounting for Income Taxes, which simplifies the accounting for income taxes by removing certain exceptions to the general principles in Topic 740 and amends existing guidance to improve consistent application of Topic 740. ASU 2019-12 is effective for fiscal years beginning after December 15, 2021, and interim periods within those fiscal years, with early adoption permitted in any interim period for which financial statements have not yet been made available for issuance. We are currently evaluating the effect that ASU 2017-12 will have on our condensed consolidated financial statements and related disclosures.
Description of Business	Description of Business. Neurocrine Biosciences, Inc., or Neurocrine Biosciences, the Company, we, our or us, was incorporated in California in 1992 and reincorporated in Delaware in 1996. Neurocrine Continental, Inc., is a Delaware corporation and a wholly owned subsidiary of Neurocrine Biosciences. We also have two wholly owned Irish subsidiaries, Neurocrine Therapeutics, Ltd. and Neurocrine Europe, Ltd. both of which were formed in December 2014 and are inactive. We are a commercial-stage biopharmaceutical company focused on discovering and developing innovative and life-changing treatments for patients with serious, challenging and under-addressed neurological, endocrine and psychiatric disorders. We specialize in targeting and interrupting disease-causing mechanisms involving the interconnected pathways of the nervous and endocrine systems. Currently, we are primarily focused on the commercialization of INGREZZA^® (valbenazine) in the United States, or US, our first US Food and Drug Administration, or FDA, approved product. In April 2017, we received FDA approval of our first marketed product, INGREZZA, for the treatment of adults with tardive dyskinesia, or TD. Shortly after receiving FDA approval, we began commercializing INGREZZA in the US using a specialty sales force primarily focused on educating physicians who treat patients with TD, including psychiatrists and neurologists. In addition to our first marketed product, our collaboration partner, AbbVie Inc., or AbbVie, received approval of ORILISSA^® (elagolix) for the management of moderate to severe endometriosis pain in women from the FDA in July 2018 and Health Canada in October 2018. We receive royalties at tiered percentage rates on any net sales of ORILISSA. In April 2020, we received FDA approval for ONGENTYS^® (opicapone) as an adjunctive therapy to levodopa/DOPA decarboxylase inhibitors in adult Parkinson's disease patients. Our late-stage pipeline includes crinecerfont (NBI-74788) for the treatment of congenital adrenal hyperplasia, or CAH, in adult patients, elagolix for the treatment of heavy menstrual bleeding, or HMB, associated with uterine fibroids in women, valbenazine for the treatment of chorea in adult patients with Huntington’s disease, or HD, and NBIb-1817 (VY-AADC) for the treatment of advanced Parkinson’s disease patients with motor fluctuations that are refractory to medical management. Our product candidates for uterine fibroids and advanced Parkinson’s disease are partnered with AbbVie and Voyager Therapeutics, Inc., or Voyager, respectively. Our early-stage clinical pipeline includes crinecerfont for the treatment of CAH in pediatric patients, elagolix for the treatment of polycystic ovary syndrome, or PCOS, in women, a vesicular monoamine transporter 2, or VMAT2, inhibitor with potential use in the treatment of neurologic and psychiatric disorders and NBI-921352 (XEN901), a clinical-stage candidate with potential in epilepsy. Our product candidate for PCOS is partnered with AbbVie. In January 2020, we announced a collaboration and optional licensing agreement with Idorsia Pharmaceuticals Ltd, granting us an option to license ACT-709478, a potent, selective, orally active and brain penetrating T-type calcium channel blocker, in clinical development for the treatment of a rare pediatric epilepsy. The option also includes a research collaboration to discover, identify and develop additional novel T-type calcium channel blockers.
Basis of Presentation	Basis of Presentation. The accompanying unaudited condensed consolidated financial statements have been prepared in accordance with accounting principles generally accepted in the United States, or GAAP, for interim financial information and with the instructions of the Securities and Exchange Commission, or SEC, on Form 10-Q and Rule 10-01 of Regulation S-X. Accordingly, they do not include all of the information and disclosures required by GAAP for complete financial statements. In the opinion of management, the condensed consolidated financial statements include all adjustments necessary, which are of a normal and recurring nature, for the fair presentation of our financial position and of the results of operations and cash flows for the periods presented. The accompanying unaudited condensed consolidated financial statements include the accounts of Neurocrine Biosciences and our wholly owned subsidiaries. All significant intercompany balances and transactions have been eliminated in consolidation. These financial statements should be read in conjunction with the audited consolidated financial statements and notes thereto for the year ended December 31, 2019, included in our Annual Report on Form 10-K, or the 2019 Form 10-K, filed with the SEC. The results of operations for the interim period shown in this report are not necessarily indicative of the results that may be expected for any other interim period or the full year. The condensed consolidated balance sheet at December 31, 2019, has been derived from the audited financial statements as of that date, but does not include all of the information and footnotes required by GAAP for complete financial statements. There were no significant changes to our significant accounting policies as disclosed in the 2019 Form 10-K, except as set forth below.
Debt Securities	Debt Securities. Debt securities consist of investments in certificates of deposit, corporate debt securities, and securities of government-sponsored entities. We classify debt securities as available-for-sale. Debt securities available-for-sale are recorded at fair value, with unrealized gains and losses included in other comprehensive income or loss, net of tax. We exclude accrued interest from both the fair value and amortized cost basis of debt securities. A debt security is placed on nonaccrual status at the time any principal or interest payments become 90 days delinquent. Interest accrued but not received for a debt security placed on nonaccrual status is reversed against interest income. Interest income includes amortization of purchase premium or discount. Premiums and discounts on debt securities are amortized using the effective interest rate method. Gains and losses on sales of debt securities are recorded on the trade date in investment income and other, net, and determined using the specific identification method.
Allowance for Credit Losses	Allowance for Credit Losses. For debt securities available-for-sale in an unrealized loss position, we first assess whether we intend to sell, or it is more likely than not that we will be required to sell the security before recovery of its amortized cost basis. If either of the criteria regarding intent or requirement to sell is met, the security’s amortized cost basis is written down to fair value through earnings. For debt securities available-for-sale that do not meet the aforementioned criteria, we evaluate whether the decline in fair value has resulted from credit losses or other factors. In making this assessment, we consider the extent to which fair value is less than amortized cost, any changes in interest rates, and any changes to the rating of the security by a rating agency, among other factors. If this assessment indicates that a credit loss exists, the present value of cash flows expected to be collected from the security is compared to the amortized cost basis of the security. If the present value of cash flows expected to be collected is less than the amortized cost basis, a credit loss exists and an allowance for credit losses is recorded, limited by the amount that the fair value is less than the amortized cost basis. Any impairment that has not been recorded through an allowance for credit losses is recognized in other comprehensive income or loss, as applicable. Accrued interest receivables on debt securities available-for-sale totaled $4.7 million at March 31, 2020. We do not measure an allowance for credit losses for accrued interest receivables. For the purposes of identifying and measuring an impairment, accrued interest is excluded from both the fair value and amortized cost basis of the debt security. Uncollectible accrued interest receivables associated with an impaired debt security are reversed against interest income upon identification of the impairment. No accrued interest receivables were written off during the three months ended March 31, 2020.
Fair Value of Financial Instruments	Fair Value of Financial Instruments. We record cash equivalents, debt securities available-for-sale and equity securities at fair value based on a fair value hierarchy that distinguishes between assumptions based on market data (observable inputs) and our own assumptions (unobservable inputs). The fair value hierarchy consists of the following three levels: Level 1 – Quoted prices (unadjusted) in active markets for identical assets or liabilities. Level 2 – Quoted prices for similar assets or liabilities in active markets, quoted prices for identical or similar assets or liabilities in markets that are not active or inputs that are observable, either directly or indirectly, for substantially the full term of the asset or liability. Level 3 – Unobservable inputs that reflect our own assumptions about the assumptions that market participants would use in pricing the asset or liability when there is little, if any, market activity for the asset or liability at the measurement date. Investments in debt securities available-for-sale are classified as Level 2 and carried at fair value. We estimate the fair value of debt securities available-for-sale by utilizing third-party pricing services. These pricing services utilize industry standard valuation models, including both income and market-based approaches, for which all significant inputs are observable, either directly or indirectly, to estimate fair value. Such inputs include market pricing based on real-time trade data for similar instruments, issuer credit spreads, benchmark yields, broker/dealer quotes and other observable inputs. We validate valuations obtained from third-party pricing services by understanding the models used, obtaining market values from other pricing sources, and analyzing data in certain instances. Investments in equity securities of certain companies that are subject to holding period restrictions longer than one year are classified as Level 3 and carried at fair value using an option pricing valuation model. The most significant assumptions within the option pricing valuation model are the stock price volatility, which is based on the historical volatility of similar companies, and the discount for lack of marketability related to the term of the restrictions. The carrying amounts of accounts receivable and accounts payable and accrued liabilities approximate their fair values due to their short-term maturities.
Recently Adopted Accounting Pronouncements	Recently Adopted Accounting Pronouncements. ASU 2016-13. On January 1, 2020, we adopted Accounting Standards Update, or ASU, 2016-13, Financial Instruments – Credit Losses (Topic 326): Measurement of Credit Losses on Financial Instruments, using the modified retrospective transition method. For debt securities available-for-sale, the standard requires an investor to determine whether a decline in the fair value below the amortized cost basis of the investment is due to credit-related factors. Credit-related impairment is recognized as an allowance for credit loss on the balance sheet with a corresponding adjustment to earnings. Credit losses are limited to the amount by which the investment’s amortized cost basis exceeds its fair value and may be subsequently reversed if conditions change. Any impairment that is not credit related is recognized in other comprehensive income or loss, as applicable, net of applicable taxes. The adoption of ASU 2016-13 did not result in a cumulative-effect adjustment to retained earnings. The comparative prior period information continues to be reported under the accounting standards in effect during those periods.

Significant Collaboration and Licensing Agreements - Additional Information (Detail) - USD ($) $ / shares in Units, shares in Millions, $ in Millions	1 Months Ended				3 Months Ended			12 Months Ended	61 Months Ended
	Jan. 31, 2019	Feb. 28, 2017	Mar. 31, 2015	Jun. 30, 2010	Mar. 31, 2020	Jun. 30, 2019	Mar. 31, 2019	Dec. 31, 2017	Mar. 31, 2020	Dec. 31, 2019
Collaborative Arrangements And Noncollaborative Arrangement Transactions [Line Items]
Revenues					$ 237.1		$ 138.4
Acquired in-process research and development							113.1
Equity securities fair value					39.4				$ 39.4	$ 55.9
Collaboration revenue
Collaborative Arrangements And Noncollaborative Arrangement Transactions [Line Items]
Revenues					6.0		2.0
AbbVie
Collaborative Arrangements And Noncollaborative Arrangement Transactions [Line Items]
Upfront payments received				$ 75.0
Collaborative arrangement right				We will be entitled to a percentage of worldwide sales of GnRH Compounds for the longer of ten years or the life of the related patent rights.
Collaboration termination notice period				180 days
AbbVie \| Development and Regulatory Milestone Payments
Collaborative Arrangements And Noncollaborative Arrangement Transactions [Line Items]
Potential development and regulatory milestone payment receipts					480.0
Revenues					135.0
AbbVie \| Commercial Milestone Payments
Collaborative Arrangements And Noncollaborative Arrangement Transactions [Line Items]
Potential commercial milestone payment receipts				$ 50.0
B I A L
Collaborative Arrangements And Noncollaborative Arrangement Transactions [Line Items]
Acquired in-process research and development		$ 30.0
Potential payments for regulatory milestones		40.0
Payments made for regulatory milestones					20.0				20.0
Potential payments for commercial milestones		$ 75.0
Voyager Therapeutics \| Collaboration and License Agreement
Collaborative Arrangements And Noncollaborative Arrangement Transactions [Line Items]
Collaboration termination notice period	180 days
Upfront payments made	$ 115.0
Equity securities cost	$ 50.0
Share price	$ 11.9625
Equity securities fair value	$ 54.7
Voyager Therapeutics \| Collaboration and License Agreement \| IPR&D
Collaborative Arrangements And Noncollaborative Arrangement Transactions [Line Items]
Acquired in-process research and development						$ 5.0	$ 113.1
Voyager Therapeutics \| Collaboration and License Agreement \| Common Stock
Collaborative Arrangements And Noncollaborative Arrangement Transactions [Line Items]
Number of shares owned	4.2
Voyager Therapeutics \| Collaboration and License Agreement \| Development, Regulatory and Commercial Milestone Payment
Collaborative Arrangements And Noncollaborative Arrangement Transactions [Line Items]
Potential milestone payments	$ 1,700.0
Xenon \| Collaboration and License Agreement
Collaborative Arrangements And Noncollaborative Arrangement Transactions [Line Items]
Upfront payments made										30.0
Equity securities cost										$ 20.0
Share price										$ 14.196
Xenon \| Collaboration and License Agreement \| Common Stock
Collaborative Arrangements And Noncollaborative Arrangement Transactions [Line Items]
Number of shares owned										1.4
Xenon \| Collaboration and License Agreement \| Development, Regulatory and Commercial Milestone Payment
Collaborative Arrangements And Noncollaborative Arrangement Transactions [Line Items]
Potential milestone payments										$ 1,700.0
Mitsubishi Tanabe
Collaborative Arrangements And Noncollaborative Arrangement Transactions [Line Items]
Upfront payments received			$ 30.0
Patent rights period			the longer of ten years or the life of the related patent rights.
Collaboration termination notice period			180 days
Potential milestone payment receipts			$ 85.0
Deferred revenue					8.1				8.1
Deferred revenue recognized					$ 1.3
Mitsubishi Tanabe \| Collaboration revenue
Collaborative Arrangements And Noncollaborative Arrangement Transactions [Line Items]
Revenues									$ 21.9
Mitsubishi Tanabe \| Development and Regulatory Milestone Payments \| Collaboration revenue
Collaborative Arrangements And Noncollaborative Arrangement Transactions [Line Items]
Revenues								$ 15.0

Net Income (Loss) Per Share

3 Months Ended

Mar. 31, 2020

Earnings Per Share [Abstract]

Net Income (Loss) Per Share

9. Net Income (Loss) Per Share

Net income per share was calculated as follows:

	Three Months Ended March 31,
(in millions, except per share data)	2020		2019
Net income (loss) - basic and diluted	$	37.4	$	(102.1	)
Weighted-average common shares outstanding:
Basic		92.6		91.1
Effect of dilutive securities:
Stock options		2.4		—
Restricted stock		0.5		—
2024 Notes		1.5		—
Diluted		97.0		91.1
Net income per share:
Basic	$	0.40	$	(1.12	)
Diluted	$	0.39	$	(1.12	)

Convertible debt instruments that may be settled entirely or partly in cash (such as the 2024 Notes) may, in certain circumstances where the borrower has the ability and intent to settle in cash, be accounted for under the treasury stock method. We issued the 2024 Notes with a combination settlement feature, which we have the ability and intent to use upon conversion of the 2024 Notes, to settle the principal amount of debt for cash and the excess of the principal portion in shares of our common stock. As a result, of the approximately 6.8 million shares underlying the 2024 Notes, only the shares required to settle the excess of the principal portion are considered under the treasury stock method.

Shares which have been excluded from diluted per share amounts because their effect would have been anti-dilutive include the following:

Three Months Ended

March 31,

(in millions)

2020

2019

Stock options, restricted stock units and convertible senior notes

3.3

8.2

Leases (Tables)

3 Months Ended

Mar. 31, 2020

Leases [Abstract]

Schedule of Description of Operating Lease

At March 31, 2020, our operating leases consisted of the following:

Address	Type	Square Feet		Commencement Date	Expiration Date
12780 El Camino Real ⁽¹⁾	Office/Laboratory		141,000	August 7, 2019	July 31, 2031
12790 El Camino Real, Suite 130 ⁽¹⁾	Office		2,000	December 1, 2019	July 31, 2031
12790 El Camino Real, Suite 150 ⁽¹⁾	Office		8,000	August 7, 2019	July 31, 2031
12790 El Camino Real, Suite 300 ⁽¹⁾	Office		28,000	December 1, 2019	July 31, 2031
12777 High Bluff Drive ⁽²⁾	Office		45,000	July 1, 2018	July 31, 2029
12790 El Camino Real, Suite 200 ⁽¹⁾	Office		28,000	February 1, 2021	July 31, 2031
12790 El Camino Real, Suite 100 ⁽¹⁾	Office		17,000	February 1, 2021	July 31, 2031

_____________________________________

Summary of Minimum Lease Payments for Operating Lease Liabilities

At March 31, 2020, the approximate future minimum lease payments under operating leases were as follows:

(in millions)	Operating Leases
Year Ending December 31,
2020 (9 months remaining)	$	6.5
2021		10.6
2022		10.9
2023		11.2
2024		11.6
Thereafter		79.7
Total operating lease payments		130.5
Less accreted interest		36.1
Total operating lease liabilities		94.4
Less current operating lease liabilities		8.8
Noncurrent operating lease liabilities	$	85.6

Condensed Consolidated Statements of Operations And Comprehensive Income (Loss) - USD ($) shares in Millions, $ in Millions	3 Months Ended
	Mar. 31, 2020	Mar. 31, 2019
Revenues:
Revenues	$ 237.1	$ 138.4
Operating expenses:
Cost of sales	2.1	1.1
Research and development	58.3	37.7
Acquired in-process research and development		113.1
Selling, general and administrative	117.8	87.5
Total operating expenses	178.2	239.4
Operating income (loss)	58.9	(101.0)
Other (expense) income:
Interest expense	(8.2)	(7.9)
Unrealized losses (gains) on equity securities	(16.5)	1.7
Investment income and other, net	4.7	4.6
Total other expense, net	(20.0)	(1.6)
Income (loss) before provision for (benefit from) income taxes	38.9	(102.6)
Provision for (benefit from) income taxes	1.5	(0.5)
Net income (loss)	37.4	(102.1)
Unrealized (loss) gain on debt securities available-for-sale, net of tax	(2.8)	1.7
Comprehensive income (loss)	$ 34.6	$ (100.4)
Net income (loss) per share, basic	$ 0.40	$ (1.12)
Net income (loss) per share, diluted	$ 0.39	$ (1.12)
Weighted average common shares outstanding, basic	92.6	91.1
Weighted average common shares outstanding, diluted	97.0	91.1
Product sales, net
Revenues:
Revenues	$ 231.1	$ 136.4
Collaboration revenue
Revenues:
Revenues	$ 6.0	$ 2.0

Fair Value Measurements (Tables)

3 Months Ended

Mar. 31, 2020

Fair Value Disclosures [Abstract]

Reconciliation of Our Investment in Restricted Equity Securities Measured at Fair Value on Recurring Basis Using Significant Unobservable Inputs (Level 3)

The following table presents a reconciliation of equity securities for the three months ended March 31, 2020, which were measured at fair value on a recurring basis using significant unobservable inputs (Level 3):

(in millions)	Equity Securities
Fair value at December 31, 2019	$	55.9
Purchases		—
Unrealized losses included in earnings		(16.5	)
Fair value at March 31, 2020	$	39.4

Investments Measured at Fair Value on Recurring Basis

Investments at March 31, 2020, which were measured at fair value on a recurring basis, consisted of the following:

			Fair Value Measurements Using
(in millions)	Fair Value		Level 1		Level 2		Level 3
Cash and cash equivalents:
Cash and money market funds	$	187.0	$	187.0	$	—	$	—
Total cash and cash equivalents		187.0		187.0		—		—
Restricted cash:
Certificates of deposit		3.2		3.2		—		—
Total restricted cash		3.2		3.2		—		—
Debt securities available-for-sale:
Commercial paper		129.7		—		129.7		—
Corporate debt securities		534.0		—		534.0		—
Securities of government-sponsored entities		156.9		—		156.9		—
Total debt securities available-for-sale		820.6		—		820.6		—
Equity securities:
Equity securities–biotechnology industry		39.4		—		—		39.4
Total equity securities		39.4		—		—		39.4
Total recurring fair value measurements	$	1,050.2	$	190.2	$	820.6	$	39.4

Investments at December 31, 2019, which were measured at fair value on a recurring basis, consisted of the following:

			Fair Value Measurements Using
(in millions)	Fair Value		Level 1		Level 2		Level 3
Cash and cash equivalents:
Cash and money market funds	$	112.3	$	112.3	$	—	$	—
Total cash and cash equivalents		112.3		112.3		—		—
Restricted cash:
Certificates of deposit		3.2		3.2		—		—
Total restricted cash		3.2		3.2		—		—
Debt securities available-for-sale:
Commercial paper		144.5		—		144.5		—
Corporate debt securities		521.9		—		521.9		—
Securities of government-sponsored entities		191.5		—		191.5		—
Total debt securities available-for-sale		857.9		—		857.9		—
Equity securities:
Equity securities–biotechnology industry		55.9		—		—		55.9
Total equity securities		55.9		—		—		55.9
Total recurring fair value measurements	$	1,029.3	$	115.5	$	857.9	$	55.9

Debt Securities - Amortized Cost, Gross Unrealized Gains and Losses, Allowance for Credit Losses and Fair Value of Debt Securities Available-For-Sale (Detail) - USD ($) $ in Millions	3 Months Ended	12 Months Ended
	Mar. 31, 2020	Dec. 31, 2019
Short-term investments
Schedule Of Available For Sale Securities [Line Items]
Amortized Cost	$ 584.1	$ 557.3
Unrealized Gain	1.6	0.9
Unrealized Loss	(1.0)
Fair Value	584.7	558.2
Short-term investments \| Commercial paper
Schedule Of Available For Sale Securities [Line Items]
Amortized Cost	129.7	144.5
Unrealized Gain	0.1
Unrealized Loss	(0.1)
Fair Value	$ 129.7	$ 144.5
Short-term investments \| Commercial paper \| Maximum
Schedule Of Available For Sale Securities [Line Items]
Available for sale securities contractual maturity	1 year	1 year
Short-term investments \| Corporate debt securities
Schedule Of Available For Sale Securities [Line Items]
Amortized Cost	$ 323.3	$ 270.5
Unrealized Gain	0.3	0.5
Unrealized Loss	(0.9)
Fair Value	$ 322.7	$ 271.0
Short-term investments \| Corporate debt securities \| Maximum
Schedule Of Available For Sale Securities [Line Items]
Available for sale securities contractual maturity	1 year	1 year
Short-term investments \| Securities of government-sponsored entities
Schedule Of Available For Sale Securities [Line Items]
Amortized Cost	$ 131.1	$ 142.3
Unrealized Gain	1.2	0.4
Fair Value	$ 132.3	$ 142.7
Short-term investments \| Securities of government-sponsored entities \| Maximum
Schedule Of Available For Sale Securities [Line Items]
Available for sale securities contractual maturity	1 year	1 year
Long-term investments
Schedule Of Available For Sale Securities [Line Items]
Amortized Cost	$ 237.8	$ 299.3
Unrealized Gain	0.3	0.5
Unrealized Loss	(2.2)	(0.1)
Fair Value	235.9	299.7
Long-term investments \| Corporate debt securities
Schedule Of Available For Sale Securities [Line Items]
Amortized Cost	213.3	250.5
Unrealized Gain	0.2	0.5
Unrealized Loss	(2.2)	(0.1)
Fair Value	$ 211.3	$ 250.9
Long-term investments \| Corporate debt securities \| Minimum
Schedule Of Available For Sale Securities [Line Items]
Available for sale securities contractual maturity	1 year	1 year
Long-term investments \| Corporate debt securities \| Maximum
Schedule Of Available For Sale Securities [Line Items]
Available for sale securities contractual maturity	2 years	2 years
Long-term investments \| Securities of government-sponsored entities
Schedule Of Available For Sale Securities [Line Items]
Amortized Cost	$ 24.5	$ 48.8
Unrealized Gain	0.1
Fair Value	$ 24.6	$ 48.8
Long-term investments \| Securities of government-sponsored entities \| Minimum
Schedule Of Available For Sale Securities [Line Items]
Available for sale securities contractual maturity	1 year	1 year
Long-term investments \| Securities of government-sponsored entities \| Maximum
Schedule Of Available For Sale Securities [Line Items]
Available for sale securities contractual maturity	2 years	2 years

Fair Value Measurements

3 Months Ended

Mar. 31, 2020

Fair Value Disclosures [Abstract]

Fair Value Measurements

4. Fair Value Measurements

Investments at March 31, 2020, which were measured at fair value on a recurring basis, consisted of the following:

			Fair Value Measurements Using
(in millions)	Fair Value		Level 1		Level 2		Level 3
Cash and cash equivalents:
Cash and money market funds	$	187.0	$	187.0	$	—	$	—
Total cash and cash equivalents		187.0		187.0		—		—
Restricted cash:
Certificates of deposit		3.2		3.2		—		—
Total restricted cash		3.2		3.2		—		—
Debt securities available-for-sale:
Commercial paper		129.7		—		129.7		—
Corporate debt securities		534.0		—		534.0		—
Securities of government-sponsored entities		156.9		—		156.9		—
Total debt securities available-for-sale		820.6		—		820.6		—
Equity securities:
Equity securities–biotechnology industry		39.4		—		—		39.4
Total equity securities		39.4		—		—		39.4
Total recurring fair value measurements	$	1,050.2	$	190.2	$	820.6	$	39.4

Investments at December 31, 2019, which were measured at fair value on a recurring basis, consisted of the following:

			Fair Value Measurements Using
(in millions)	Fair Value		Level 1		Level 2		Level 3
Cash and cash equivalents:
Cash and money market funds	$	112.3	$	112.3	$	—	$	—
Total cash and cash equivalents		112.3		112.3		—		—
Restricted cash:
Certificates of deposit		3.2		3.2		—		—
Total restricted cash		3.2		3.2		—		—
Debt securities available-for-sale:
Commercial paper		144.5		—		144.5		—
Corporate debt securities		521.9		—		521.9		—
Securities of government-sponsored entities		191.5		—		191.5		—
Total debt securities available-for-sale		857.9		—		857.9		—
Equity securities:
Equity securities–biotechnology industry		55.9		—		—		55.9
Total equity securities		55.9		—		—		55.9
Total recurring fair value measurements	$	1,029.3	$	115.5	$	857.9	$	55.9

(in millions)	Equity Securities
Fair value at December 31, 2019	$	55.9
Purchases		—
Unrealized losses included in earnings		(16.5	)
Fair value at March 31, 2020	$	39.4

At March 31, 2020, the discount for lack of marketability used in the valuation analysis of equity securities ranged from 18.5% to 30.0% (weighted average of 26.2%). The discount for lack of marketability was weighted by the relative fair value of the instruments. A significant increase (decrease) in the discount for lack of marketability in isolation would result in a significantly lower (higher) fair value measurement. Unrealized gains and losses on equity securities are included in other expense, net.

The following table presents a reconciliation of equity securities for the three months ended March 31, 2019, which were measured at fair value on a recurring basis using significant unobservable inputs (Level 3):

(in millions)	Equity Securities
Fair value at December 31, 2018	$	—
Purchases		54.7
Unrealized gains included in earnings		1.7
Fair value at March 31, 2019	$	56.4

- Definition

The entire disclosure for the fair value of financial instruments (as defined), including financial assets and financial liabilities (collectively, as defined), and the measurements of those instruments as well as disclosures related to the fair value of non-financial assets and liabilities. Such disclosures about the financial instruments, assets, and liabilities would include: (1) the fair value of the required items together with their carrying amounts (as appropriate); (2) for items for which it is not practicable to estimate fair value, disclosure would include: (a) information pertinent to estimating fair value (including, carrying amount, effective interest rate, and maturity, and (b) the reasons why it is not practicable to estimate fair value; (3) significant concentrations of credit risk including: (a) information about the activity, region, or economic characteristics identifying a concentration, (b) the maximum amount of loss the entity is exposed to based on the gross fair value of the related item, (c) policy for requiring collateral or other security and information as to accessing such collateral or security, and (d) the nature and brief description of such collateral or security; (4) quantitative information about market risks and how such risks are managed; (5) for items measured on both a recurring and nonrecurring basis information regarding the inputs used to develop the fair value measurement; and (6) for items presented in the financial statement for which fair value measurement is elected: (a) information necessary to understand the reasons for the election, (b) discussion of the effect of fair value changes on earnings, (c) a description of [similar groups] items for which the election is made and the relation thereof to the balance sheet, the aggregate carrying value of items included in the balance sheet that are not eligible for the election; (7) all other required (as defined) and desired information.

+ References + Details

Debt Securities - Gross Unrealized Losses and Fair Value Available-For-Sale Investments in Unrealized Loss Position (Detail) - USD ($) $ in Millions	Mar. 31, 2020	Dec. 31, 2019
Schedule Of Available For Sale Securities [Line Items]
Less Than 12 Months, Fair Value	$ 429.7
Less Than 12 Months, Unrealized Loss	(3.2)
Total Fair Value	429.7
Total Unrealized Loss	(3.2)
Commercial paper
Schedule Of Available For Sale Securities [Line Items]
Less Than 12 Months, Fair Value	19.9
Less Than 12 Months, Unrealized Loss	(0.1)
Total Fair Value	19.9
Total Unrealized Loss	(0.1)
Corporate debt securities
Schedule Of Available For Sale Securities [Line Items]
Less Than 12 Months, Fair Value	409.8	$ 186.1
Less Than 12 Months, Unrealized Loss	(3.1)	(0.1)
12 Months or Longer, Fair Value		0.0
12 Months or Longer, Unrealized Loss		0.0
Total Fair Value	409.8	186.1
Total Unrealized Loss	$ (3.1)	$ (0.1)

Condensed Consolidated Statements of Stockholders' Equity - USD ($) shares in Millions, $ in Millions	Total	Common Stock	Additional Paid in Capital	Accumulated Other Comprehensive Income (Loss)	Accumulated Deficit
Begining balance at Dec. 31, 2018	$ 480.8	$ 0.1	$ 1,660.4	$ (1.9)	$ (1,177.8)
Begining balance (in shares) at Dec. 31, 2018		90.8
Net income (loss)	(102.1)				(102.1)
Unrealized gain (loss) on debt securities available-for-sale, net of tax	1.7			1.7
Share-based compensation expense	15.8		15.8
Cumulative-effect adjustment to equity due to adoptionof ASU 2016-02 \| ASU 2016-02	8.0				8.0
Issuance of common stock for vested restricted stock units (in shares)		0.4
Issuance of common stock for stock option exercises	2.6		2.6
Issuance of common stock for stock option exercises (in shares)		0.1
Issuance of common stock for employee stock purchase plan	2.5		2.5
Ending balance at Mar. 31, 2019	409.3	$ 0.1	1,681.3	(0.2)	(1,271.9)
Ending balance (in shares) at Mar. 31, 2019		91.3
Begining balance at Dec. 31, 2019	636.9	$ 0.1	1,768.1	1.4	(1,132.7)
Begining balance (in shares) at Dec. 31, 2019		92.3
Net income (loss)	37.4				37.4
Unrealized gain (loss) on debt securities available-for-sale, net of tax	(2.8)			(2.8)
Share-based compensation expense	22.8		22.8
Issuance of common stock for vested restricted stock units (in shares)		0.4
Issuance of common stock for stock option exercises	3.3		3.3
Issuance of common stock for stock option exercises (in shares)		0.1
Issuance of common stock for employee stock purchase plan	2.7		2.7
Ending balance at Mar. 31, 2020	$ 700.3	$ 0.1	$ 1,796.9	$ (1.4)	$ (1,095.3)
Ending balance (in shares) at Mar. 31, 2020		92.8

Debt Securities

3 Months Ended

Mar. 31, 2020

Investments Debt And Equity Securities [Abstract]

Debt Securities

3. Debt Securities

(in millions)	Contractual Maturity	Amortized Cost		Unrealized Gain		Unrealized Loss			Allowance for Credit Losses		Fair Value
Commercial paper	Within 1 year	$	129.7	$	0.1	$	(0.1	)	$	—	$	129.7
Corporate debt securities	Within 1 year		323.3		0.3		(0.9	)		—		322.7
Securities of government-sponsored entities	Within 1 year		131.1		1.2		—			—		132.3
blank		$	584.1	$	1.6	$	(1.0	)	$	—	$	584.7
blank
Corporate debt securities	1 to 2 years	$	213.3	$	0.2	$	(2.2	)	$	—	$	211.3
Securities of government-sponsored entities	1 to 2 years		24.5		0.1		—			—		24.6
		$	237.8	$	0.3	$	(2.2	)	$	—	$	235.9

(in millions)	Contractual Maturity	Amortized Cost		Unrealized Gain		Unrealized Loss			Fair Value
Commercial paper	Within 1 year	$	144.5	$	—	$	—		$	144.5
Corporate debt securities	Within 1 year		270.5		0.5		—			271.0
Securities of government-sponsored entities	Within 1 year		142.3		0.4		—			142.7
blank		$	557.3	$	0.9	$	—		$	558.2
blank
Corporate debt securities	1 to 2 years	$	250.5	$	0.5	$	(0.1	)	$	250.9
Securities of government-sponsored entities	1 to 2 years		48.8		—		—			48.8
		$	299.3	$	0.5	$	(0.1	)	$	299.7

	Less Than 12 Months					12 Months or Longer				Total
(in millions)	Fair Value		Unrealized Loss			Fair Value		Unrealized Loss		Fair Value		Unrealized Loss
Commercial paper	$	19.9	$	(0.1	)	$	—	$	—	$	19.9	$	(0.1	)
Corporate debt securities		409.8		(3.1	)		—		—		409.8		(3.1	)
blank	$	429.7	$	(3.2	)	$	—	$	—	$	429.7	$	(3.2	)

At March 31, 2020, our security portfolio consisted of 187 securities, of which 107 were in an unrealized loss position, related to investments in debt securities available-for-sale, as discussed below:

Commercial paper. Our investments in commercial paper are of high credit quality (rated A1 or higher). Unrealized losses on these investments were primarily due to changes in interest rates. We do not intend to sell these investments and it is not more likely than not that we will be required to sell these investments before recovery of their amortized costs basis.

Corporate debt securities. Our investments in corporate debt securities are of high credit quality (rated AA- or higher). Unrealized losses on these investments were primarily due to changes in interest rates. We do not intend to sell these investments and it is not more likely than not that we will be required to sell these investments before recovery of their amortized cost basis.

Less Than 12 Months

12 Months or Longer

Total

(in millions)

Fair

Value

Unrealized

Loss

Fair

Value

Unrealized

Loss

Fair

Value

Unrealized

Loss

Corporate debt securities

186.1

(0.1

)

—

186.1

(0.1

)

Net Income (Loss) Per Share - Schedule of Net Income Per Share (Detail) - USD ($) $ / shares in Units, shares in Millions, $ in Millions	3 Months Ended
	Mar. 31, 2020	Mar. 31, 2019
Subsidiary Sale Of Stock [Line Items]
Net income (loss) - basic and diluted	$ 37.4	$ (102.1)
Weighted-average common shares outstanding:
Weighted average common shares outstanding, basic	92.6	91.1
Effect of dilutive securities:
Diluted	97.0	91.1
Net income per share:
Basic	$ 0.40	$ (1.12)
Diluted	$ 0.39	$ (1.12)
2.25% Convertible Senior Notes due 2024
Effect of dilutive securities:
2024 Notes	1.5
Stocks Options
Effect of dilutive securities:
Effect of dilutive securities	2.4
Restricted Stock
Effect of dilutive securities:
Effect of dilutive securities	0.5

Inventories - Summary of Inventories (Detail) - USD ($) $ in Millions	Mar. 31, 2020	Dec. 31, 2019
Inventory Disclosure [Abstract]
Raw materials	$ 17.8	$ 14.1
Work in process	1.1	1.5
Finished goods	2.3	1.7
Total inventories	$ 21.2	$ 17.3

Leases - Additional Information (Detail) - USD ($) $ in Millions	3 Months Ended
	Mar. 31, 2020	Mar. 31, 2019	Dec. 31, 2019
Leases [Abstract]
Operating lease cost	$ 2.5	$ 1.9
Cash paid for cashflows from operating lease	$ 2.1	$ 1.6
Operating lease, weighted average remaining lease term	11 years		11 years 4 months 24 days
Operating lease, weighted average discount rate, percent	5.80%		5.80%

Subsequent Events	3 Months Ended
Subsequent Events	Mar. 31, 2020
Subsequent Events [Abstract]
Subsequent Events	In April 2020, we received FDA approval for ONGENTYS as an adjunctive therapy to levodopa/DOPA decarboxylase inhibitors in adult Parkinson's disease patients. FDA approval of ONGENTYS for Parkinson’s disease triggered a milestone payment of $20.0 million.

Subsequent Events - Additional Information (Detail) - B I A L - USD ($) $ in Millions	Apr. 24, 2020	Feb. 28, 2017
Subsequent Event [Line Items]
Potential payments for regulatory milestones		$ 40.0
Subsequent Event
Subsequent Event [Line Items]
Potential payments for regulatory milestones	$ 20.0

Leases - Summary of Minimum Lease Payments for Operating Lease Liabilities (Parenthetical) (Detail) $ in Millions	Mar. 31, 2020 USD ($)
Leases [Abstract]
Non-cancelable future minimum lease payments for operating leases that have not yet commenced	$ 28.3

Net Income (Loss) Per Share - Additional Information (Detail) shares in Millions	3 Months Ended
	Mar. 31, 2020 shares
2.25% Convertible Senior Notes due 2024
Short Term Debt [Line Items]
Shares issued to settle notes at initial conversion rate	6.8

Organization and Significant Accounting Policies - Additional Information (Detail)	3 Months Ended
	Mar. 31, 2020 USD ($)
Accounting Policies [Abstract]
Accrued interest receivables write-off threshold period	90 days
Accrued interest receivables write-off	$ 0
Accrued interest receivables	$ 4,700,000

Fair Value Measurements - Additional Information (Detail) - Discount for Lack of Marketability	Mar. 31, 2020
Minimum
Fair Value Assets And Liabilities Measured On Recurring And Nonrecurring Basis [Line Items]
Valuation analysis of equity securities	18.50%
Maximum
Fair Value Assets And Liabilities Measured On Recurring And Nonrecurring Basis [Line Items]
Valuation analysis of equity securities	30.00%
Weighted Average
Fair Value Assets And Liabilities Measured On Recurring And Nonrecurring Basis [Line Items]
Valuation analysis of equity securities	26.20%

Net Income (Loss) Per Share - Schedule of Anti-Dilutive Shares Excluded from Diluted Per Share Amounts (Detail) - shares shares in Millions	3 Months Ended
	Mar. 31, 2020	Mar. 31, 2019
Stock Options Restricted Stock Units And Convertible Senior Notes
Antidilutive Securities Excluded From Computation Of Earnings Per Share [Line Items]
Anti-dilutive shares excluded from diluted per share amounts	3.3	8.2

Convertible Senior Notes - Debt Net of Discounts and Deferred Financing Costs (Detail) - USD ($) $ in Millions	Mar. 31, 2020	Dec. 31, 2019
Debt Disclosure [Abstract]
Principal	$ 517.5	$ 517.5
Deferred financing costs	(6.6)	(6.9)
Debt discount, net	(96.8)	(101.8)
Net carrying amount	$ 414.1	$ 408.8

Leases - Schedule of Description of Operating Lease (Parenthetical) (Detail) $ in Millions	Mar. 31, 2020 USD ($)	Dec. 31, 2019 USD ($)	Aug. 31, 2019 USD ($) RenewalOption	May 31, 2018 USD ($)
Leases [Line Items]
Restricted cash	$ 3.2	$ 3.2
12780/90 El Camino Real Lease Agreement
Leases [Line Items]
Number of times to renew the lease contract \| RenewalOption			2
Lease extension period			10 years
12780/90 El Camino Real Lease Agreement \| Letter of Credit
Leases [Line Items]
Restricted cash			$ 3.0
12777 High Bluff Drive Lease Agreement \| Letter of Credit
Leases [Line Items]
Restricted cash		$ 0.2		$ 1.0

Debt Securities - Additional Information (Detail)	Mar. 31, 2020 Security
Investments Debt And Equity Securities [Abstract]
Number of debt securities available for sale in unrealized loss position	107
Number of debt securities available for sale	187