Intercept Pharmaceuticals (ICPT) 10-Q 8 May 19 2019 Q1 Quarterly report Financial data

Document And Entity Information

Document And Entity Information	3 Months Ended
	Mar. 31, 2019shares
Document and Entity Information [Abstract]
Entity Registrant Name	INTERCEPT PHARMACEUTICALS, INC.
Entity Central Index Key	0001270073
Current Fiscal Year End Date	--12-31
Entity Filer Category	Large Accelerated Filer
Trading Symbol	icpt
Entity Common Stock, Shares Outstanding	29,777,078
Document Type	10-Q
Amendment Flag	false
Document Period End Date	Mar. 31, 2019
Document Fiscal Period Focus	Q1
Document Fiscal Year Focus	2019
Entity Current Reporting Status	Yes

Condensed Consolidated Balance

Condensed Consolidated Balance Sheets - USD ($) $ in Thousands	Mar. 31, 2019	Dec. 31, 2018
Current assets:
Cash and cash equivalents	$ 54,724	$ 43,248
Investment debt securities, available-for-sale	298,818	392,912
Accounts receivable, net	29,440	25,694
Prepaid expenses and other current assets	19,819	20,571
Total current assets	402,801	482,425
Fixed assets, net	7,464	10,411
Inventory, net	7,370	7,108
Security deposits	8,340	9,223
Other assets	12,283
Total assets	438,258	509,167
Current liabilities:
Accounts payable, accrued expenses and other liabilities	101,886	105,109
Short-term interest payable	3,738	7,475
Short-term portion of deferred revenue	2,717	1,621
Total current liabilities	108,341	114,205
Long-term liabilities:
Long-term debt	375,351	371,250
Long-term other liabilities	9,162	3,771
Long-term portion of deferred revenue	405	811
Total liabilities	493,259	490,037
Commitments and contingencies (Note 15)
Stockholders’ (deficit) equity:
Common stock par value $0.001 per share; 45,000,000 shares authorized; 29,780,321 and 29,693,876 shares issued and outstanding as of March 31, 2019 and December 31, 2018, respectively	30	30
Additional paid-in capital	1,815,193	1,800,144
Accumulated other comprehensive loss, net	(1,169)	(2,259)
Accumulated deficit	(1,869,055)	(1,778,785)
Total stockholders’ (deficit) equity	(55,001)	19,130
Total liabilities and stockholders’ (deficit) equity	$ 438,258	$ 509,167

Condensed Consolidated Balanc_2

Condensed Consolidated Balance Sheets (Parenthetical) - $ / shares	Mar. 31, 2019	Dec. 31, 2018
Condensed Consolidated Balance Sheets
Common stock, par value (in dollars per share)	$ 0.001	$ 0.001
Common stock, authorized	45,000,000	45,000,000
Common stock, shares, issued	29,777,078	29,693,876
Common stock, shares, outstanding	29,777,078	29,693,876

Condensed Consolidated Statemen

Condensed Consolidated Statements of Operations - USD ($) shares in Thousands, $ in Thousands	3 Months Ended
	Mar. 31, 2019	Mar. 31, 2018
Revenue	$ 52,252	$ 35,963
Operating expenses:
Cost of sales	574	280
Selling, general and administrative	77,227	62,467
Research and development	58,396	48,672
Total operating expenses	136,197	111,419
Operating loss	(83,945)	(75,456)
Other income (expense):
Interest expense	(7,839)	(7,509)
Other income, net	1,514	1,375
Total other income (expense)	(6,325)	(6,134)
Net loss	$ (90,270)	$ (81,590)
Net loss per common and potential common share:
Basic and diluted	$ (3.03)	$ (3.22)
Weighted average common and potential common shares outstanding:
Basic and diluted	29,760	25,309
Product [Member]
Revenue	$ 51,847	$ 35,158
License [Member]
Revenue	$ 405	$ 805

Condensed Consolidated Statem_2

Condensed Consolidated Statements of Comprehensive Loss - USD ($) $ in Thousands	3 Months Ended
	Mar. 31, 2019	Mar. 31, 2018
Condensed Consolidated Statements of Comprehensive Loss
Net loss	$ (90,270)	$ (81,590)
Net changes related to available-for-sale investment debt securities:
Unrealized gains (losses) on investment debt securities	803	(374)
Reclassification adjustment for realized gains on investment debt securities included in other income, net	4
Net unrealized gains (losses) on investment debt securities	807	(374)
Foreign currency translation gains	283	517
Comprehensive loss	$ (89,180)	$ (81,447)

Condensed Consolidated Statem_3

Condensed Consolidated Statements of Changes in Stockholders’ (Deficit) Equity - USD ($) shares in Thousands, $ in Thousands	Common Stock [Member]	Additional Paid-in Capital [Member]	Accumulated Other Comprehensive Income (Loss) [Member]	Retained Earnings [Member]	Total
Balance at Dec. 31, 2017	$ 25	$ 1,486,690	$ (786)	$ (1,469,543)	$ 16,386
Balance (in shares) at Dec. 31, 2017	25,173
Stock-based compensation		12,305			12,305
Net proceeds from exercise of stock options		481			481
Net proceeds from exercise of stock options (in shares)	159
Other comprehensive income			143		143
Net loss				(81,590)	(81,590)
Balance at Mar. 31, 2018	$ 25	1,499,476	(643)	(1,551,133)	(52,275)
Balance (in shares) at Mar. 31, 2018	25,332
Balance at Dec. 31, 2018	$ 30	1,800,144	(2,259)	(1,778,785)	19,130
Balance (in shares) at Dec. 31, 2018	29,694
Stock-based compensation		14,897			14,897
Net proceeds from exercise of stock options		943			$ 943
Net proceeds from exercise of stock options (in shares)	83				17
Employee withholding taxes related to stock-based awards		(791)			$ (791)
Other comprehensive income			1,090		1,090
Net loss				(90,270)	(90,270)
Balance at Mar. 31, 2019	$ 30	$ 1,815,193	$ (1,169)	$ (1,869,055)	$ (55,001)
Balance (in shares) at Mar. 31, 2019	29,777

Condensed Consolidated Statem_4

Condensed Consolidated Statements of Cash Flows - USD ($) $ in Thousands	3 Months Ended
	Mar. 31, 2019	Mar. 31, 2018
Cash flows from operating activities:
Net loss	$ (90,270)	$ (81,590)
Adjustments to reconcile net loss to net cash used in operating activities:
Stock-based compensation	14,897	12,305
(Accretion) amortization of (discount) premium on investment debt securities	(299)	502
Amortization of deferred financing costs	406	373
Depreciation and amortization	2,400	1,290
Gain on lease termination	(1,995)
Loss on the disposal of fixed assets	2,683	901
Accretion of debt discount	3,695	3,399
Changes in operating assets:
Prepaid expenses and other current assets	752	(3,920)
Accounts receivable	(3,746)	(443)
Inventory	(262)	(4,458)
Security deposits	883	8,415
Other assets	(19,716)
Changes in operating liabilities:
Accounts payable, accrued expenses and other current liabilities	(800)	(20,690)
Operating lease liabilities	(1,638)
Long-term other liabilities	12,632	(407)
Interest payable	(3,737)	(3,738)
Deferred revenue	690	(805)
Net cash used in operating activities	(83,425)	(88,866)
Cash flows from investing activities:
Purchases of investment debt securities	(5,212)	(28,466)
Sales and maturities of investment debt securities	100,412	95,273
Purchases of equipment, leasehold improvements, and furniture and fixtures	(733)	(89)
Net cash provided by investing activities	94,467	66,718
Cash flows from financing activities:
Proceeds from exercise of options, net	943	481
Payments of employee withholding taxes related to stock-based awards	(791)
Net cash provided by financing activities	152	481
Effect of exchange rate changes	282	525
Net increase (decrease) in cash and cash equivalents	11,476	(21,142)
Cash and cash equivalents - beginning of period	43,248	70,013
Cash and cash equivalents - end of period	$ 54,724	$ 48,871

Overview of Business

Overview of Business	3 Months Ended
	Mar. 31, 2019
Overview of Business [Abstract]
Overview of Business	1. Overview of Business Intercept Pharmaceuticals, Inc. (the “Company”) is a biopharmaceutical company focused on the development and commercialization of novel therapeutics to treat progressive non-viral liver diseases, including primary biliary cholangitis (“PBC”) and nonalcoholic steatohepatitis (“NASH”). The Company currently has one marketed product, Ocaliva (obeticholic acid or “OCA”). Founded in 2002 in New York, the Company has operations in the United States, Europe and Canada.

Basis of Presentation

Basis of Presentation	3 Months Ended
	Mar. 31, 2019
Overview of Business [Abstract]
Basis of Presentation	2. Basis of Presentation The Company’s financial statements have been prepared in conformity with accounting principles generally accepted in the United States of America (“U.S. GAAP”). All intercompany balances and transactions have been eliminated in consolidation. Certain information that is normally required by U.S. GAAP has been condensed or omitted in accordance with rules and regulations of the Securities and Exchange Commission (“SEC”). Operating results for the three months ended March 31, 2019 are not necessarily indicative of the results that may be expected for any future period or for the year ending December 31, 2019. In the opinion of management, these unaudited condensed consolidated financial statements include all normal and recurring adjustments considered necessary for a fair presentation of these interim unaudited condensed consolidated financial statements. These unaudited condensed consolidated financial statements should be read in conjunction with the Company’s audited consolidated financial statements and the notes thereto for the year ended December 31, 2018, included in the Company’s Annual Report on Form 10‑K for the year ended December 31, 2018 filed with the SEC. Use of Estimates The preparation of these unaudited condensed consolidated financial statements in conformity with U.S. GAAP requires management to make estimates and judgments that affect the reported amounts of assets and liabilities, the disclosure of assets and liabilities at the date of the financial statements and the reported amounts of revenues and expenses during the reporting period. Actual results may differ from these estimates.

Summary of Significant Accounti

Summary of Significant Accounting Policies	3 Months Ended
	Mar. 31, 2019
Summary of Significant Accounting Policies [Abstract]
Summary of Significant Accounting Policies	3. Summary of Significant Accounting Policies The Company’s significant accounting policies are described in Note 2 of Notes to Consolidated Financial Statements included in its Annual Report on Form 10‑K for the year ended December 31, 2018. Leases The Company determines if an arrangement is a lease at inception and records right-of-use (“ROU”) assets and lease liabilities on the condensed consolidated balance sheets at lease commencement based on the present value of remaining lease payments over the lease term. The Company only considers payments that are fixed and determinable at the time of commencement. Operating leases are included in other assets, accounts payable, accrued expenses and other liabilities and long-term other liabilities on the condensed consolidated balance sheets. Operating lease liabilities are recognized based on the present value of the future minimum lease payments discounted by the Company’s incremental borrowing rate. The Company measures ROU assets based on the corresponding lease liability adjusted for (i) payments made to the lessor at or before the commencement date, (ii) initial direct costs incurred and (iii) tenant incentives under the lease. The Company’s lease terms may include options to extend or terminate the lease when it is reasonably certain that it will exercise that option. Lease expense for minimum lease payments is recognized on a straight-line basis over the lease term. For short-term leases, the Company records rent expense in its consolidated statements of operations on a straight-line basis over the lease term and records variable lease payments as incurred. Additional information and disclosures are contained in Note 8 — Operating Leases below. Recent Accounting Pronouncements Recently Adopted Accounting Pronouncements In February 2016, the Financial Accounting Standards Board (“FASB”) established Accounting Standards Codification (“ASC”) Topic 842, Leases (“ASC 842”), by issuing Accounting Standards Update (“ASU”) No. 2016-02, which requires lessees to recognize leases on-balance sheet and disclose key information about leasing arrangements. ASC 842 was subsequently amended by ASU No. 2018-01, “Land Easement Practical Expedient for Transition to Topic 842”; ASU No. 2018-10, “Codification Improvements to Topic 842, Leases”; and ASU No. 2018-11, “Targeted Improvements”. The new standard establishes a ROU model that requires a lessee to recognize a ROU asset and lease liability on the balance sheet for all leases with a term longer than 12 months. Leases will be classified as finance or operating, with classification affecting the pattern and classification of expense recognition in the income statement. A modified retrospective transition approach is required, applying the new standard to all leases existing at the date of initial application. An entity may choose to use either (i) its effective date or (ii) the beginning of the earliest comparative period presented in the financial statements as its date of initial application. The Company adopted the new standard on January 1, 2019 using the effective date as the date of initial application. The new standard provides a number of optional practical expedients in transition. The Company elected the “package of practical expedients”, which permits the Company to not reassess under the new standard the Company’s prior conclusions about lease identification, lease classification and initial direct costs. The new standard also provides practical expedients for an entity’s ongoing accounting. The Company elected the short-term lease recognition exemption for all leases that qualify. This means, for those leases that qualify, the Company will not recognize ROU assets or lease liabilities, and this includes not recognizing ROU assets or lease liabilities for existing short-term leases of those assets in transition. The Company also elected the practical expedient to not separate lease and non-lease components for all of the Company’s leases. Upon adoption, the Company recognized additional operating liabilities of $25.4 million, with corresponding ROU assets of $19.6 million based on the present value of the remaining minimum rental payments under current leasing standards for existing operating leases. In July 2017, the FASB issued ASU No. 2017-11, “Earnings Per Share (Topic 260), Distinguishing Liabilities from Equity (Topic 480) and Derivatives and Hedging (Topic 815): I. Accounting for Certain Financial Instruments with Down Round Features; II. Replacement of the Indefinite Deferral for Mandatorily Redeemable Financial Instruments of Certain Nonpublic Entities and Certain Mandatorily Redeemable Noncontrolling Interests with a Scope Exception” (“ASU 2017-11”). Part I of this update addresses the complexity of accounting for certain financial instruments with down round features. Down round features are features of certain equity-linked instruments (or embedded features) that result in the strike price being reduced on the basis of the pricing of future equity offerings. Current accounting guidance creates cost and complexity for entities that issue financial instruments (such as warrants and convertible instruments) with down round features that require fair value measurement of the entire instrument or conversion option. Part II of this update addresses the difficulty of navigating ASC Topic 480, Distinguishing Liabilities from Equity , because of the existence of extensive pending content in the FASB Accounting Standards Codification. This pending content is the result of the indefinite deferral of accounting requirements about mandatorily redeemable financial instruments of certain nonpublic entities and certain mandatorily redeemable noncontrolling interests. The amendments in Part II of this update do not have an accounting effect. This ASU is effective for fiscal years, and interim periods within those years, beginning after December 15, 2018. The Company adopted ASU 2017-11 on January 1, 2019 and its adoption did not have any impact on the Company’s consolidated financial statements and related disclosures. In June 2018, the FASB issued ASU No. 2018-07, “Improvements to Nonemployee Share-Based Payment Accounting” (“ASU 2018-07”), which simplifies the accounting for share-based payments granted to nonemployees for goods and services. Under this ASU, most of the guidance on such payments to nonemployees would be aligned with the requirements for share-based payments granted to employees. The changes take effect for public companies for fiscal years starting after December 15, 2018, including interim periods within that fiscal year. For all other entities, the amendments are effective for fiscal years beginning after December 15, 2019, and interim periods within fiscal years beginning after December 15, 2020. Early adoption is permitted, but no earlier than an entity’s adoption date of ASC Topic 606, Revenue from Contracts with Customers (“ASC 606”). The Company adopted ASU 2018-07 on January 1, 2019 on a modified retrospective basis through a cumulative-effect adjustment to equity by remeasuring, on that date, the fair value of all outstanding unvested stock options that had been granted to nonemployees. The adoption did not have a material impact on the Company’s consolidated financial statements and related disclosures. Recent Accounting Pronouncements to be Adopted In June 2016 , the FASB issued ASU No. 2016-13, “Financial Instruments-Credit Losses: Measurement of Credit Losses on Financial Instruments” (“ASU 2016-13”), which replaces the incurred loss impairment methodology under current U.S. GAAP with a methodology that reflects expected credit losses and requires consideration of a broader range of reasonable and supportable information to inform credit loss estimates. The Company will be required to use a forward-looking expected credit loss model for accounts receivables, loans, and other financial instruments. Credit losses relating to available-for-sale debt securities will also be recorded through an allowance for credit losses rather than as a reduction in the amortized cost basis of the securities. This guidance is effective for fiscal years, and interim periods within those fiscal years, beginning after December 15, 2019 and must be adopted using a modified retrospective approach, with certain exceptions . The Company is currently evaluating the impact of this standard on its consolidated financial statements and related disclosures. In August 2018, the FASB issued ASU No. 2018-13, “Fair Value Measurement (Topic 820): Disclosure Framework — Changes to the Disclosure Requirements for Fair Value Measurement” (“ASU 2018-13”), which makes a number of changes meant to add, modify or remove certain disclosure requirements associated with the movement amongst or hierarchy associated with Level 1, Level 2 and Level 3 fair value measurements. This guidance is effective for fiscal years, and interim periods within those fiscal years, beginning after December 15, 2019. Early adoption is permitted upon issuance of the update. The Company plans to adopt ASU 2018-13 effective January 1, 2020 and does not expect the adoption of this guidance to have a material impact on the Company’s consolidated financial statements and related disclosures.

Significant Agreements

Significant Agreements	3 Months Ended
	Mar. 31, 2019
Significant Agreements [Abstract]
Significant Agreements	4. Significant Agreements Sumitomo Dainippon Pharma Co., Ltd. In March 2011, the Company entered into an exclusive license agreement (the “Original Sumitomo Agreement”) with Sumitomo Dainippon Pharma Co., Ltd. (“Sumitomo Dainippon”), pursuant to which the Company granted to Sumitomo Dainippon an exclusive license to research, develop and commercialize OCA for the treatment of PBC and NASH in Japan and China (excluding Taiwan) and an option to research, develop and commercialize OCA in certain countries outside of such territories (the “Country Option”). The Company received an upfront payment from Sumitomo Dainippon of $15.0 million under the terms of the Original Sumitomo Agreement. In May 2014, Sumitomo Dainippon exercised the Country Option in part to add Korea as part of its licensed territories and paid the Company a $1.0 million upfront fee in connection therewith. In February 2018, the Company and Sumitomo Dainippon entered into Amendment No. 3 (the “Sumitomo Amendment”) to the Original Sumitomo Agreement (as amended, the “Sumitomo Agreement”). Pursuant to the Sumitomo Amendment, (i) Sumitomo Dainippon agreed to return the rights to develop and commercialize OCA in Japan and Korea and waived its rights to the Country Option, (ii) the Company agreed to forego any further milestone or royalty payments relating to the development and commercialization of OCA in Japan and Korea and (iii) certain milestone payment obligations with respect to the development and commercialization of OCA were adjusted. In addition, the Company and Sumitomo Dainippon agreed that if certain clinical development milestones in China are not met by December 31, 2020, Sumitomo Dainippon may choose either to make a milestone payment to the Company or terminate the Sumitomo Agreement. Sumitomo Dainippon may also terminate the Sumitomo Agreement in its entirety or on an indication-by-indication basis at any time upon 90 days’ written notice. As of March 31, 2019, the Company had achieved $6.0 million of development milestones under the Sumitomo Agreement. The Company may be eligible to receive additional milestone payments under the Sumitomo Agreement in an aggregate amount of up to approximately $23.0 million based on the occurrence of certain clinical trial and regulatory-related events and tiered royalty payments up to the mid-twenties in percentage terms based on net sales of OCA products in China (excluding Taiwan). Sumitomo Dainippon is responsible for the costs of developing and commercializing OCA in its territory. The Company has concluded that Sumitomo Dainippon does not represent a customer of the Company, and therefore the Sumitomo Agreement is outside of the scope of ASC 606. The Company has accounted, and continues to account, for this agreement under the legacy accounting guidance. Under ASC Topic 605, Revenue Recognition , the Company evaluated this agreement and determined that it is a revenue arrangement with multiple deliverables, or performance obligations. The Company’s substantive performance obligations under this agreement include an exclusive license to its technology, technical and scientific support to the development plan and participation on a joint steering committee. The Company determined that these performance obligations represent a single unit of accounting, since, initially, the license does not have stand-alone value to Sumitomo Dainippon without the Company’s technical expertise and steering committee participation during the development of OCA. The development period is currently estimated as continuing through June 2020 and, as such, the $15.0 million upfront payment is being recognized ratably over this period. During the three months ended March 31, 2019 and 2018, the Company recorded licensing revenue of approximately $0.4 million and $0.8 million, respectively, under this agreement. Included in licensing revenue for the three months ended March 31, 2018 is $0.4 million related to the accelerated recognition, as a result of the Sumitomo Amendment, of the remaining portion of deferred revenue associated with the $1.0 million upfront payment that the Company received under the Original Sumitomo Agreement in connection with Sumitomo Dainippon’s exercise of the Country Option with respect to Korea. The Company recognizes milestone payments when the associated milestones are achieved. As of March 31, 2019 and December 31, 2018, the Company had recorded deferred revenues of $2.0 million and $2.4 million, respectively, under this agreement.

Cash, Cash Equivalents and Inve

Cash, Cash Equivalents and Investment Debt Securities	3 Months Ended
	Mar. 31, 2019
Cash, Cash Equivalents, and Investment Debt Securities [Abstract]
Cash, Cash Equivalents, and Investment Debt Securities	5. Cash, Cash Equivalents and Investment Debt Securities The following table summarizes the Company’s cash, cash equivalents and investment debt securities as of March 31, 2019 and December 31, 2018: As of March 31, 2019 Gross Gross Unrealized Unrealized Amortized Cost Gains Losses Fair Value (in thousands) Cash and cash equivalents: Cash and money market funds $ 54,724 $ — $ — $ 54,724 Investment debt securities: Commercial paper 8,987 — (2) 8,985 Corporate debt securities 280,291 221 (127) 280,385 U.S. government and agency securities 9,438 12 (2) 9,448 Total investment debt securities 298,716 233 (131) 298,818 Total cash, cash equivalents and investment debt securities $ 353,440 $ 233 $ (131) $ 353,542 As of December 31, 2018 Gross Gross Unrealized Unrealized Amortized Cost Gains Losses Fair Value (in thousands) Cash and cash equivalents: Cash and money market funds $ 43,248 $ — $ — $ 43,248 Investment debt securities: Commercial paper 34,353 — (26) 34,327 Corporate debt securities 349,854 27 (704) 349,177 U.S. government and agency securities 9,410 5 (7) 9,408 Total investment debt securities 393,617 32 (737) 392,912 Total cash, cash equivalents and investment debt securities $ 436,865 $ 32 $ (737) $ 436,160 As of March 31, 2019, the Company held a total of twenty positions that were in a continuous unrealized loss position for twelve months or longer. The Company has determined that the unrealized losses are deemed to be temporary impairments as of March 31, 2019. The Company believes that the unrealized losses generally are caused by increases in the risk premiums required by market participants rather than an adverse change in cash flows or a fundamental weakness in the credit quality of the issuer or underlying assets. Because the Company has the ability and intent to hold these investments until a recovery of fair value, which may be maturity, it does not consider the investments to be other-than-temporarily impaired at March 31, 2019.

Fixed Assets, Net

Fixed Assets, Net	3 Months Ended
	Mar. 31, 2019
Fixed Assets, Net [Abstract]
Fixed Assets, Net	6. Fixed Assets, Net Fixed assets are stated at cost and depreciated or amortized using the straight-line method based on useful lives as follows: Useful lives (Years) March 31, 2019 December 31, 2018 (in thousands) Office equipment and software 3 $ 4,051 $ 3,986 Leasehold improvements Over life of lease 10,406 14,464 Furniture and fixtures 7 4,017 3,907 Subtotal 18,474 22,357 Less: accumulated depreciation (11,010) (11,946) Fixed assets, net $ 7,464 $ 10,411

Inventory, Net

Inventory, Net	3 Months Ended
	Mar. 31, 2019
Inventory, Net [Abstract]
Inventory, Net	7. Inventory, Net Inventories are stated at the lower of cost or market. Inventories consisted of the following: March 31, 2019 December 31, 2018 (in thousands) Work-in-process $ 7,224 $ 7,019 Finished goods 146 89 Inventory, net $ 7,370 $ 7,108

Operating Leases

Operating Leases	3 Months Ended
	Mar. 31, 2019
Operating Leases
Operating Leases	8. Operating Leases The Company leases various office spaces under non-cancelable operating leases with original lease periods expiring between 2019 and 2024. T he Company subleases one of its office spaces to a third party. The Company also enters into leases for equipment. A number of the Company’s leases include one or more options to renew, with renewal terms that can extend the lease term. The exercise of lease renewal options is typically at the sole discretion of the Company; therefore, all renewals to extend the lease terms are not included in the ROU assets and lease liabilities as they are not reasonably certain of exercise. The Company regularly evaluates the renewal options and when they are reasonably certain of exercise, includes the renewal period in the lease term. These operating leases do not contain material variable rent payments, residual value guarantees, covenants, or other restrictions. The Company has elected the practical expedient to exclude short-term leases from its ROU assets and lease liabilities; therefore leases with an initial term of 12 months or less are not recorded on the balance sheet. The Company recognizes lease expense for these leases on a straight-line basis over the lease term. The Company elected the practical expedient not to separate non-lease components from all leases. As the Company’s leases do not provide an implicit rate, the Company uses an incremental borrowing rate based on the information available at the lease commencement date in determining the present value of the lease payments. The Company’s incremental borrowing rate is the estimated rate that would be required to pay for a collateralized borrowing equal to the total lease payment over the lease term. The Company estimates its incremental borrowing rate based on an analysis of publicly traded debt securities of companies with credit and financial profiles similar to its own. Operating lease assets and liabilities are classified on the condensed consolidated balance sheets as follows: Leases Classification March 31, 2019 Assets (in thousands) Operating lease assets Other assets $ 12,283 Total leased assets $ 12,283 Liabilities Current Operating lease liabilities Accounts payable, accrued expenses and other liabilities $ 6,701 Noncurrent Operating lease liabilities Long-term other liabilities 9,158 Total lease liabilities $ 15,859 Operating lease costs for the three months ended March 31, 2019 are as follows: Three Months Ended Lease Cost Classification March 31, 2019 (in thousands) Operating lease cost Selling, general and administrative expenses $ 1,678 Short-term lease cost Selling, general and administrative expenses 826 Variable lease cost Selling, general and administrative expenses 224 Sublease income Other income, net (180) Net lease cost $ 2,548 The weighted-average remaining term of the Company’s operating leases was 2.9 years and the weighted-average discount rate used to measure the present value of the Company’s operating lease liabilities was 5.0% as of March 31, 2019. Maturities of the Company’s operating lease liabilities, which do not include short-term leases, as of March 31, 2019 are as follows: Maturity of Lease Liabilities Operating leases (in thousands) 2019 $ 5,658 2020 6,194 2021 2,879 2022 948 2023 948 Thereafter 395 Total lease payments 17,022 Less: Present value discount (1,163) Total operating lease liabilities $ 15,859 Cash payments included in the measurement of the Company’s lease liabilities were $1.9 million for the three months ended March 31, 2019.

Accounts Payable, Accrued Expen

Accounts Payable, Accrued Expenses and Other Liabilities	3 Months Ended
	Mar. 31, 2019
Accounts Payable, Accrued Expenses and Other Liabilities [Abstract]
Accounts Payable, Accrued Expenses and Other Liabilities	9. Accounts Payable, Accrued Expenses and Other Liabilities Accounts payable, accrued expenses and other liabilities consisted of the following: March 31, 2019 December 31, 2018 (in thousands) Accounts payable $ 18,580 $ 11,765 Accrued employee compensation 11,521 20,335 Accrued contracted services 46,624 54,681 Other liabilities 18,460 18,328 Operating lease liabilities 6,701 — Accounts payable, accrued expenses and other liabilities $ 101,886 $ 105,109

Fair Value Measurements

Fair Value Measurements	3 Months Ended
	Mar. 31, 2019
Fair Value Measurements [Abstract]
Fair Value Measurements	10. Fair Value Measurements The carrying amounts of the Company’s receivables and payables approximate their fair value due to their short maturities. Accounting principles provide guidance for using fair value to measure assets and liabilities. The guidance includes a three-level hierarchy of valuation techniques used to measure fair value, defined as follows: · Unadjusted Quoted Prices — The fair value of an asset or liability is based on unadjusted quoted prices in active markets for identical assets or liabilities (Level 1). · Pricing Models with Significant Observable Inputs — The fair value of an asset or liability is based on information derived from either an active market quoted price, which may require further adjustment based on the attributes of the financial asset or liability being measured, or an inactive market transaction (Level 2). · Pricing Models with Significant Unobservable Inputs — The fair value of an asset or liability is primarily based on internally derived assumptions surrounding the timing and amount of expected cash flows for the financial instrument. Therefore, these assumptions are unobservable in either an active or inactive market (Level 3). The Company considers an active market as one in which transactions for the asset or liability occur with sufficient frequency and volume to provide pricing information on an ongoing basis. Conversely, the Company views an inactive market as one in which there are few transactions for the asset or liability, the prices are not current, or price quotations vary substantially either over time or among market makers. Where appropriate, non-performance risk, or that of a counterparty, is considered in determining the fair values of liabilities and assets, respectively. The Company’s cash deposits and money market funds are classified within Level 1 of the fair value hierarchy because they are valued using bank balances or quoted market prices. Investments are classified as Level 2 instruments based on market pricing and other observable inputs. Financial assets carried at fair value are classified in the tables below in one of the three categories described above: Fair Value Measurements Using Total Level 1 Level 2 Level 3 (in thousands) March 31, 2019 Assets: Money market funds (included in cash and cash equivalents) $ 40,607 $ 40,607 $ — $ — Available-for-sale debt securities: Commercial paper 8,985 — 8,985 — Corporate debt securities 280,385 — 280,385 — U.S. government and agency securities 9,448 — 9,448 — Total financial assets $ 339,425 $ 40,607 $ 298,818 $ — December 31, 2018 Assets: Money market funds (included in cash and cash equivalents) $ 11,647 $ 11,647 $ — $ — Available-for-sale debt securities: Commercial paper 34,327 — 34,327 — Corporate debt securities 349,177 — 349,177 — U.S. government and agency securities 9,408 — 9,408 — Total financial assets $ 404,559 $ 11,647 $ 392,912 $ — The estimated fair value of marketable debt securities (commercial paper, corporate debt securities and U.S. government and agency securities), by contractual maturity, are as follows: Fair Value as of March 31, 2019 December 31, 2018 (in thousands) Due in one year or less $ 269,399 $ 319,717 Due after one year through two years 29,419 73,195 Total investments in debt securities $ 298,818 $ 392,912 Actual maturities may differ from contractual maturities because issuers may have the right to call or prepay obligations without call or prepayment penalties.

Long-Term Debt

Long-Term Debt	3 Months Ended
	Mar. 31, 2019
Long-Term Debt [Abstract]
Long-Term Debt	11. Long-Term Debt Debt, net of discounts and deferred financing costs, consisted of the following: March 31, 2019 December 31, 2018 (in thousands) Long-term debt $ 375,351 $ 371,250 Less current portion — — Long-term debt outstanding $ 375,351 $ 371,250 On July 6, 2016, the Company issued and sold $460.0 million aggregate principal amount of 3.25% Convertible Senior Notes due 2023 (the “Convertible Notes”). The Company received net proceeds from the sale of the Convertible Notes of $447.6 million, after deducting underwriting discounts and estimated offering expenses of approximately $12.4 million. The Company used approximately $38.4 million of such net proceeds to fund the cost of the Capped Call Transactions (as defined below) that were entered into in connection with the issuance of the Convertible Notes. The Convertible Notes were issued pursuant to an indenture, as supplemented by a first supplemental indenture, each dated as of July 6, 2016 (collectively, the “Indenture”), by and between the Company and U.S. Bank National Association, as trustee. The Convertible Notes are senior unsecured obligations of the Company, bear interest at a fixed rate of 3.25% per year (payable semi-annually on January 1 and July 1 of each year, beginning on January 1, 2017) and will mature on July 1, 2023, unless earlier repurchased, redeemed or converted. Holders may convert their Convertible Notes at their option at any time prior to the close of business on the business day immediately preceding January 1, 2023 only under the following circumstances: (i) during any calendar quarter commencing after September 30, 2016, if the last reported sale price of the Company’s common stock for at least 20 trading days (whether or not consecutive) during the period of 30 consecutive trading days ending on the last trading day of the immediately preceding calendar quarter is greater than or equal to 130% of the conversion price on each applicable trading day; (ii) during the five business day period after any five consecutive trading day period in which the trading price (as defined in the Indenture) per $1,000 principal amount of Convertible Notes for each trading day of such five consecutive trading day period was less than 98% of the product of the last reported sale price of the Company’s common stock and the conversion rate on each such trading day; (iii) if the Company calls any or all of the Convertible Notes for redemption, at any time prior to the close of business on the scheduled trading day immediately preceding the redemption date; or (iv) upon the occurrence of specified corporate events. On or after January 1, 2023 until the close of business on the second scheduled trading day immediately preceding the maturity date, holders may convert their Convertible Notes at any time, regardless of the foregoing circumstances. Upon conversion of the Convertible Notes, the Company will pay or deliver, as the case may be, cash, shares of the Company’s common stock (and cash in lieu of any fractional shares) or a combination of cash and shares of the Company’s common stock, at the Company’s election. The initial conversion rate of the Convertible Notes is 5.0358 shares of the Company’s common stock per $1,000 principal amount of Convertible Notes, which is equivalent to an initial conversion price of approximately $198.58 per share of the Company’s common stock. The conversion rate is subject to adjustment upon the occurrence of certain events but will not be adjusted for any accrued and unpaid interest. If the Company undergoes a fundamental change (as defined in the Indenture), holders may require the Company to repurchase for cash all or any portion of their Convertible Notes at a fundamental change repurchase price equal to 100% of the principal amount of the Convertible Notes to be repurchased, plus accrued and unpaid interest to, but excluding, the fundamental change repurchase date. In addition, if certain make-whole fundamental changes occur, the Company will, in certain circumstances, increase the conversion rate for any Convertible Notes converted in connection with such make-whole fundamental change. The Company may not redeem the Convertible Notes prior to July 6, 2021. The Company may redeem for cash all or part of the Convertible Notes, at its option, on or after July 6, 2021, if the last reported sale price of the Company’s 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 (including the last trading day of such period) ending on, and including, the trading day immediately preceding the date on which the Company provides notice of redemption at a redemption price equal to 100% of the principal amount of the Convertible Notes to be redeemed, plus accrued and unpaid interest to, but excluding, the redemption date. The Indenture provides for customary events of default. On June 30, 2016, in connection with the pricing of the Convertible Notes, the Company entered into privately-negotiated capped call transactions (the “Base Capped Call Transactions”) with each of Royal Bank of Canada, UBS AG, London Branch, and Credit Suisse Capital LLC (the “Option Counterparties”). On July 1, 2016, in connection with the underwriters’ exercise of their over-allotment option in full, the Company entered into additional capped call transactions (the “Additional Capped Call Transactions” and, together with the Base Capped Call Transactions, the “Capped Call Transactions”) with the Option Counterparties. The Capped Call Transactions are expected generally to reduce the potential dilution with respect to the Company’s common stock and/or offset the cash payments the Company would be required to make in excess of the principal amount of converted Convertible Notes, as the case may be, upon conversion of the Convertible Notes in the event that the market price per share of the Company’s common stock, as measured under the terms of the Capped Call Transactions, is greater than the strike price of the Capped Call Transactions, which initially corresponds to the conversion price of the Convertible Notes and is subject to anti-dilution adjustments substantially similar to those applicable to the conversion rate of the Convertible Notes. The cap price of the Capped Call Transactions is initially $262.2725 per share, and is subject to certain adjustments under the terms of the Capped Call Transactions. If, however, the market price per share of the Company’s common stock, as measured under the terms of the Capped Call Transactions, exceeds the cap price of the Capped Call Transactions, there would nevertheless be dilution and/or there would not be an offset of such potential cash payments, in each case, upon conversion of the Convertible Notes to the extent that such market price exceeds the cap price of the Capped Call Transactions. In accordance with ASC Subtopic 470‑20, “Debt with Conversion and Other Options,” the Company used an effective interest rate of 8.4% to determine the liability component of the Convertible Notes. This resulted in the recognition of $334.4 million as the liability component of the Convertible Notes and the recognition of the residual $113.1 million as the debt discount with a corresponding increase to additional paid-in capital for the equity component of the Convertible Notes. Interest expense was $7.8 million and $7.5 million for the three months ended March 31, 2019 and 2018, respectively, related to the Convertible Notes. Accrued interest on the Convertible Notes was approximately $3.7 million and $7.5 million as of March 31, 2019 and December 31, 2018, respectively. The Company recorded debt issuance costs of $12.4 million, which are being amortized using the effective interest method. As of March 31, 2019, $8.4 million of debt issuance costs are recorded on the unaudited condensed consolidated balance sheet in Long-term debt, in accordance with ASU No. 2015‑03, “Interest – Imputation of Interest (Subtopic 835‑30): Simplifying the Presentation of Debt Issuance Costs.” As of March 31, 2019, $460.0 million aggregate principal amount of the Convertible Notes was outstanding.

Product Revenue, Net

Product Revenue, Net	3 Months Ended
	Mar. 31, 2019
Product Revenue, Net [Abstract]
Product Revenue, Net	12. Product Revenue, Net The Company recognized net sales of Ocaliva of $51.8 million and $35.2 million for the three months ended March 31, 2019 and 2018, respectively. The table below summarizes consolidated product revenue, net by region: Three Months Ended March 31, 2019 2018 (in thousands) Product revenue, net: U.S. $ 37,991 $ 28,513 ex-U.S. 13,856 6,645 Total product revenue, net $ 51,847 $ 35,158

Stockholders' (Deficit) Equity

Stockholders' (Deficit) Equity	3 Months Ended
	Mar. 31, 2019
Stockholders' Equity [Abstract]
Stockholders' Equity	13. Stockholders’ (Deficit) Equity On April 9, 2018, the Company issued and sold (i) 2,695,313 shares of common stock in a registered public offering (including 351,563 shares issued and sold upon the exercise in full of the underwriters’ option to purchase additional shares), at a price to the public of $64.00 per share (the “Public Offering”) and (ii) 1,562,500 shares of common stock (the “Private Placement Shares”) in a concurrent private placement (the “Concurrent Private Placement”) exempt from the registration requirements of the Securities Act of 1933, as amended, at a purchase price per share equivalent to the price to the public set in the Public Offering and pursuant to a securities purchase agreement (the “Securities Purchase Agreement”) that the Company entered into with the purchasers in the Concurrent Private Placement (the “Private Placement Purchasers”). Pursuant to the Securities Purchase Agreement, the Company granted to the Private Placement Purchasers certain registration rights requiring the Company, upon request of the Private Placement Purchasers (and/or certain affiliate transferees thereof) on or after June 5, 2018 and subject to certain terms and conditions, to register the resale by such Private Placement Purchasers (and/or such affiliates) of the Private Placement Shares held by them. Pursuant to the Securities Purchase Agreement, such registration rights expired on April 4, 2019.

Stock Compensation

Stock Compensation	3 Months Ended
	Mar. 31, 2019
Stock Compensation [Abstract]
Stock Compensation	14. Stock Compensation The Company’s 2012 Equity Incentive Plan (“2012 Plan”) became effective upon the pricing of its initial public offering in October 2012. At the same time, the Company’s 2003 Stock Incentive Plan (“2003 Plan”) was terminated and 555,843 shares available under the 2003 Plan were added to the 2012 Plan. On January 1, 2019, the number of shares available for issuance under the 2012 Plan increased by 1,187,599 shares, as a result of the automatic increase provisions thereof. The estimated fair value of the stock options granted in the three months ended March 31, 2019 was determined utilizing a Black-Scholes option-pricing model at the date of grant. The fair value of the restricted stock units (“RSUs”) granted in the three months ended March 31, 2019 was determined utilizing the closing price of the Company’s common stock on the date of grant. The fair value of the performance restricted stock units (“PRSUs”) granted in the three months ended March 31, 2019 was determined utilizing the Monte Carlo simulation method. The following table summarizes stock option activity during the three months ended March 31, 2019: Weighted Average Number Weighted Remaining Aggregate of Options Average Contractual Intrinsic Value (in thousands) Exercise Price Term (years) (in thousands) Outstanding at December 31, 2018 1,873 $ 97.63 7.5 $ 45,381 Granted 392 $ 110.82 — $ — Exercised (17) $ 54.60 — $ — Cancelled/forfeited (14) $ 86.41 — $ — Expired (10) $ 142.49 — $ — Outstanding at March 31, 2019 2,224 $ 100.15 7.7 $ 57,032 Expected to vest 1,180 $ 93.78 8.9 $ 26,111 Exercisable 1,044 $ 107.35 6.4 $ 30,921 The aggregate intrinsic value of options is calculated as the difference between the exercise price of the underlying options and the deemed fair value of the Company’s common stock for those options that had exercise prices lower than the deemed fair value of the Company’s common stock. As of March 31, 2019, the total compensation cost related to non-vested option awards not yet recognized is approximately $63.1 million with a weighted average remaining vesting period of 1.5 years. The Company estimated the fair value of stock options granted in the periods presented utilizing a Black-Scholes option-pricing model utilizing the following assumptions: Three Months Ended March 31, 2019 2018 Volatility 87.0 - 87.2 % 60.9 % Expected term (in years) 6.0 6.0 Risk-free rate 2.5 - 2.9 % 2.4 - 2.7 % Expected dividend yield — % — % Effective January 1, 2019, the Company changed its expected volatility assumption to be estimated based on the historical stock price volatility of the Company over the expected term. In prior years, the expected volatility was estimated based on historical volatility information of publicly-traded peer companies. The following table summarizes the aggregate RSU, restricted stock award (“RSA”), PRSU and performance restricted share award (“PRSA”) activity during the three months ended March 31, 2019: Weighted Number of Average Grant Date Awards Fair Value (in thousands) Non-vested awards at December 31, 2018 773 $ 76.10 Granted 296 $ 116.48 Vested (162) $ 71.62 Forfeited (12) $ 76.68 Non-vested awards at March 31, 2019 895 $ 90.25 As of March 31, 2019, there was approximately $69.8 million of total unrecognized compensation expense related to unvested RSUs, RSAs, PRSUs and PRSAs, which is expected to be recognized over a weighted average period of 1.6 years. During the three months ended March 31, 2019, the Company granted a total of 57,800 PRSUs to certain of the Company’s executive officers. The performance criterion for such PRSUs is based on the Total Shareholder Return (“TSR”) of the Company’s common stock relative to the TSR of the companies comprising the S&P Biotechnology Select Industry Index (the “TSR Peer Group”) over a 3‑year performance period and is accounted for as a market condition under ASC Topic 718, Compensation – Stock Compensation . The TSR for the Company or a member of the TSR Peer Group is calculated by dividing (a) the difference of the ending average stock price minus the beginning average stock price by (b) the beginning average stock price. The beginning average stock price equals the average closing stock price over the one calendar month period prior to the beginning of the performance period, after adjusting for dividends, as applicable. The ending average stock price equals the average closing price over the one calendar month period ending on the last day of the performance period, after adjusting for dividends, as applicable. The Company’s relative TSR is then used to calculate the payout percentage, which may range from zero percent (0%) to one hundred and fifty percent (150%) of the target award. The Company utilized a Monte Carlo Simulation to determine the grant date fair value of such PRSUs. The Company recorded approximately $0.7 million of stock-based compensation related to such PRSUs during the three months ended March 31, 2019. The Company accounts for all forfeitures when they occur. Ultimately, the actual expense recognized over the vesting period will be for only those shares that vest and are not forfeited. The Company has in the past, and may in the future, grant performance-based awards with vesting terms based on the achievement of specified goals. To the extent such awards do not contain a market condition, the Company recognizes no expense until achievement of the performance requirement is deemed probable. Stock-based compensation expense has been reported in the Company’s condensed consolidated statements of operations as follows: Three Months Ended March 31, 2019 2018 (in thousands) Selling, general and administrative $ 11,331 $ 8,676 Research and development 3,566 3,629 Total stock-based compensation $ 14,897 $ 12,305

Commitments and Contingencies

Commitments and Contingencies	3 Months Ended
	Mar. 31, 2019
Commitments and Contingencies Disclosure [Abstract]
Commitments and Contingencies	15. Commitments and Contingencies Legal Proceedings The Company is involved in various disputes, governmental inquiries and investigations, legal proceedings and litigation in the course of its business, including the matters described below and, from time to time, intellectual property, employment and other litigation. These matters, which could result in damages, fines or other administrative, civil or criminal remedies, liabilities or penalties, are often complex and the outcome of such matters is often uncertain. The Company may from time to time enter into settlements to resolve such matters. On September 27, 2017, a purported shareholder class action, initially styled DeSmet v. Intercept Pharmaceuticals, Inc., et al, was filed in the United States District Court for the Southern District of New York, naming the Company and certain of its officers as defendants. The Court appointed lead plaintiffs in the lawsuit on June 1, 2018, and the lead plaintiffs filed an amended complaint on July 31, 2018, captioned Hou Liu and Amy Fu v. Intercept Pharmaceuticals, Inc., et al., naming the Company and certain of its current and former officers as defendants. The lead plaintiffs claim to be suing on behalf of anyone who purchased or otherwise acquired the Company’s common stock between June 9, 2016 and September 20, 2017. This lawsuit alleges that material misrepresentations and/or omissions of material fact were made in the Company’s public disclosures during the period from June 9, 2016 to September 20, 2017, in violation of Sections 10(b) and 20(a) of the Securities Exchange Act of 1934, as amended (the “Exchange Act”), and Rule 10b-5 promulgated thereunder. The alleged improper disclosures relate to statements regarding Ocaliva dosing, use and pharmacovigilance-related matters, as well as the Company’s operations, financial performance and prospects. The plaintiffs seek unspecified monetary damages on behalf of the putative class, an award of costs and expenses, including attorney’s fees, and rescissory damages. On September 14, 2018, the Company filed a motion to dismiss the amended complaint. Separately, on January 5, 2018, a follow-on derivative suit, styled Davis v. Pruzanski et al., was filed in New York state court by shareholder Gregg Davis based on substantially the same allegations as those set forth in the securities case. On December 1, 2017, a purported shareholder demand was made on the Company based on substantially the same allegations as those set forth in the securities case. While the Company believes that it has a number of valid defenses to the claims described above and intends to vigorously defend itself, the matters are in the early stages of litigation and no assessment can be made as to the likely outcome of the matters or whether they will be material to the Company. Accordingly, an estimate of the potential loss, or range of loss, if any, to the Company relating to the matters is not possible at this time. In May 2018, the Company received a subpoena from the SEC requesting information in connection with the Company’s patient assistance program and certain of the Company’s commercial activities. The SEC’s letter enclosing the subpoena states that the investigation and the subpoena do not mean that the Company or anyone else has broken the law, or that the SEC has a negative opinion of any person, entity or security. The Company is cooperating fully with the SEC in this matter. At this time, the Company is unable to predict whether any proceeding may be instituted in connection with the subpoena, or the outcome of any such proceeding, if instituted.

Net Loss Per Share

Net Loss Per Share	3 Months Ended
	Mar. 31, 2019
Net loss per common and potential common share:
Net Loss Per Share	16. Net Loss Per Share Basic loss per share is computed by dividing net loss attributable to common stockholders (numerator) by the weighted average number of common shares outstanding (denominator) during the period. For the three months ended March 31, 2019 and 2018, as the Company was in a net loss position, the diluted loss per share computations for such periods did not assume the conversion of the Convertible Notes, exercise of stock options or vesting of RSUs or PRSUs as they would have had an anti-dilutive effect on loss per share. The following potentially dilutive securities have been excluded from the computations of diluted weighted average shares outstanding as of March 31, 2019 and 2018, as the inclusion thereof would have been anti-dilutive: Three Months Ended March 31, 2019 2018 (In thousands) Convertible Notes 2,316 2,316 Options 2,224 2,230 Restricted stock units 645 847 Total 5,185 5,393

Basis of Presentation (Policy)

Basis of Presentation (Policy)	3 Months Ended
	Mar. 31, 2019
Overview of Business [Abstract]
Use of Estimates	Use of Estimates The preparation of these unaudited condensed consolidated financial statements in conformity with U.S. GAAP requires management to make estimates and judgments that affect the reported amounts of assets and liabilities, the disclosure of assets and liabilities at the date of the financial statements and the reported amounts of revenues and expenses during the reporting period. Actual results may differ from these estimates

Summary of Significant Accoun_2

Summary of Significant Accounting Policies (Policy)	3 Months Ended
	Mar. 31, 2019
Summary of Significant Accounting Policies [Abstract]
Leases	Leases The Company determines if an arrangement is a lease at inception and records right-of-use (“ROU”) assets and lease liabilities on the condensed consolidated balance sheets at lease commencement based on the present value of remaining lease payments over the lease term. The Company only considers payments that are fixed and determinable at the time of commencement. Operating leases are included in other assets, accounts payable, accrued expenses and other liabilities and long-term other liabilities on the condensed consolidated balance sheets. Operating lease liabilities are recognized based on the present value of the future minimum lease payments discounted by the Company’s incremental borrowing rate. The Company measures ROU assets based on the corresponding lease liability adjusted for (i) payments made to the lessor at or before the commencement date, (ii) initial direct costs incurred and (iii) tenant incentives under the lease. The Company’s lease terms may include options to extend or terminate the lease when it is reasonably certain that it will exercise that option. Lease expense for minimum lease payments is recognized on a straight-line basis over the lease term. For short-term leases, the Company records rent expense in its consolidated statements of operations on a straight-line basis over the lease term and records variable lease payments as incurred. Additional information and disclosures are contained in Note 8 — Operating Leases below.
Recent Accounting Pronouncements	Recent Accounting Pronouncements Recently Adopted Accounting Pronouncements In February 2016, the Financial Accounting Standards Board (“FASB”) established Accounting Standards Codification (“ASC”) Topic 842, Leases (“ASC 842”), by issuing Accounting Standards Update (“ASU”) No. 2016-02, which requires lessees to recognize leases on-balance sheet and disclose key information about leasing arrangements. ASC 842 was subsequently amended by ASU No. 2018-01, “Land Easement Practical Expedient for Transition to Topic 842”; ASU No. 2018-10, “Codification Improvements to Topic 842, Leases”; and ASU No. 2018-11, “Targeted Improvements”. The new standard establishes a ROU model that requires a lessee to recognize a ROU asset and lease liability on the balance sheet for all leases with a term longer than 12 months. Leases will be classified as finance or operating, with classification affecting the pattern and classification of expense recognition in the income statement. A modified retrospective transition approach is required, applying the new standard to all leases existing at the date of initial application. An entity may choose to use either (i) its effective date or (ii) the beginning of the earliest comparative period presented in the financial statements as its date of initial application. The Company adopted the new standard on January 1, 2019 using the effective date as the date of initial application. The new standard provides a number of optional practical expedients in transition. The Company elected the “package of practical expedients”, which permits the Company to not reassess under the new standard the Company’s prior conclusions about lease identification, lease classification and initial direct costs. The new standard also provides practical expedients for an entity’s ongoing accounting. The Company elected the short-term lease recognition exemption for all leases that qualify. This means, for those leases that qualify, the Company will not recognize ROU assets or lease liabilities, and this includes not recognizing ROU assets or lease liabilities for existing short-term leases of those assets in transition. The Company also elected the practical expedient to not separate lease and non-lease components for all of the Company’s leases. Upon adoption, the Company recognized additional operating liabilities of $25.4 million, with corresponding ROU assets of $19.6 million based on the present value of the remaining minimum rental payments under current leasing standards for existing operating leases. In July 2017, the FASB issued ASU No. 2017-11, “Earnings Per Share (Topic 260), Distinguishing Liabilities from Equity (Topic 480) and Derivatives and Hedging (Topic 815): I. Accounting for Certain Financial Instruments with Down Round Features; II. Replacement of the Indefinite Deferral for Mandatorily Redeemable Financial Instruments of Certain Nonpublic Entities and Certain Mandatorily Redeemable Noncontrolling Interests with a Scope Exception” (“ASU 2017-11”). Part I of this update addresses the complexity of accounting for certain financial instruments with down round features. Down round features are features of certain equity-linked instruments (or embedded features) that result in the strike price being reduced on the basis of the pricing of future equity offerings. Current accounting guidance creates cost and complexity for entities that issue financial instruments (such as warrants and convertible instruments) with down round features that require fair value measurement of the entire instrument or conversion option. Part II of this update addresses the difficulty of navigating ASC Topic 480, Distinguishing Liabilities from Equity , because of the existence of extensive pending content in the FASB Accounting Standards Codification. This pending content is the result of the indefinite deferral of accounting requirements about mandatorily redeemable financial instruments of certain nonpublic entities and certain mandatorily redeemable noncontrolling interests. The amendments in Part II of this update do not have an accounting effect. This ASU is effective for fiscal years, and interim periods within those years, beginning after December 15, 2018. The Company adopted ASU 2017-11 on January 1, 2019 and its adoption did not have any impact on the Company’s consolidated financial statements and related disclosures. In June 2018, the FASB issued ASU No. 2018-07, “Improvements to Nonemployee Share-Based Payment Accounting” (“ASU 2018-07”), which simplifies the accounting for share-based payments granted to nonemployees for goods and services. Under this ASU, most of the guidance on such payments to nonemployees would be aligned with the requirements for share-based payments granted to employees. The changes take effect for public companies for fiscal years starting after December 15, 2018, including interim periods within that fiscal year. For all other entities, the amendments are effective for fiscal years beginning after December 15, 2019, and interim periods within fiscal years beginning after December 15, 2020. Early adoption is permitted, but no earlier than an entity’s adoption date of ASC Topic 606, Revenue from Contracts with Customers (“ASC 606”). The Company adopted ASU 2018-07 on January 1, 2019 on a modified retrospective basis through a cumulative-effect adjustment to equity by remeasuring, on that date, the fair value of all outstanding unvested stock options that had been granted to nonemployees. The adoption did not have a material impact on the Company’s consolidated financial statements and related disclosures. Recent Accounting Pronouncements to be Adopted In June 2016 , the FASB issued ASU No. 2016-13, “Financial Instruments-Credit Losses: Measurement of Credit Losses on Financial Instruments” (“ASU 2016-13”), which replaces the incurred loss impairment methodology under current U.S. GAAP with a methodology that reflects expected credit losses and requires consideration of a broader range of reasonable and supportable information to inform credit loss estimates. The Company will be required to use a forward-looking expected credit loss model for accounts receivables, loans, and other financial instruments. Credit losses relating to available-for-sale debt securities will also be recorded through an allowance for credit losses rather than as a reduction in the amortized cost basis of the securities. This guidance is effective for fiscal years, and interim periods within those fiscal years, beginning after December 15, 2019 and must be adopted using a modified retrospective approach, with certain exceptions . The Company is currently evaluating the impact of this standard on its consolidated financial statements and related disclosures. In August 2018, the FASB issued ASU No. 2018-13, “Fair Value Measurement (Topic 820): Disclosure Framework — Changes to the Disclosure Requirements for Fair Value Measurement” (“ASU 2018-13”), which makes a number of changes meant to add, modify or remove certain disclosure requirements associated with the movement amongst or hierarchy associated with Level 1, Level 2 and Level 3 fair value measurements. This guidance is effective for fiscal years, and interim periods within those fiscal years, beginning after December 15, 2019. Early adoption is permitted upon issuance of the update. The Company plans to adopt ASU 2018-13 effective January 1, 2020 and does not expect the adoption of this guidance to have a material impact on the Company’s consolidated financial statements and related disclosures.

Fair Value Measurements (Policy

Fair Value Measurements (Policy)	3 Months Ended
	Mar. 31, 2019
Fair Value Measurements [Abstract]
Fair Value of Financial Instruments	The carrying amounts of the Company’s receivables and payables approximate their fair value due to their short maturities. Accounting principles provide guidance for using fair value to measure assets and liabilities. The guidance includes a three-level hierarchy of valuation techniques used to measure fair value, defined as follows: · Unadjusted Quoted Prices — The fair value of an asset or liability is based on unadjusted quoted prices in active markets for identical assets or liabilities (Level 1). · Pricing Models with Significant Observable Inputs — The fair value of an asset or liability is based on information derived from either an active market quoted price, which may require further adjustment based on the attributes of the financial asset or liability being measured, or an inactive market transaction (Level 2). · Pricing Models with Significant Unobservable Inputs — The fair value of an asset or liability is primarily based on internally derived assumptions surrounding the timing and amount of expected cash flows for the financial instrument. Therefore, these assumptions are unobservable in either an active or inactive market (Level 3). The Company considers an active market as one in which transactions for the asset or liability occur with sufficient frequency and volume to provide pricing information on an ongoing basis. Conversely, the Company views an inactive market as one in which there are few transactions for the asset or liability, the prices are not current, or price quotations vary substantially either over time or among market makers. Where appropriate, non-performance risk, or that of a counterparty, is considered in determining the fair values of liabilities and assets, respectively. The Company’s cash deposits and money market funds are classified within Level 1 of the fair value hierarchy because they are valued using bank balances or quoted market prices. Investments are classified as Level 2 instruments based on market pricing and other observable inputs.

Cash, Cash Equivalents and In_2

Cash, Cash Equivalents and Investment Debt Securities (Tables)	3 Months Ended
	Mar. 31, 2019
Cash, Cash Equivalents, and Investment Debt Securities [Abstract]
Cash, Cash Equivalents and Investment Debt Securities	The following table summarizes the Company’s cash, cash equivalents and investment debt securities as of March 31, 2019 and December 31, 2018: As of March 31, 2019 Gross Gross Unrealized Unrealized Amortized Cost Gains Losses Fair Value (in thousands) Cash and cash equivalents: Cash and money market funds $ 54,724 $ — $ — $ 54,724 Investment debt securities: Commercial paper 8,987 — (2) 8,985 Corporate debt securities 280,291 221 (127) 280,385 U.S. government and agency securities 9,438 12 (2) 9,448 Total investment debt securities 298,716 233 (131) 298,818 Total cash, cash equivalents and investment debt securities $ 353,440 $ 233 $ (131) $ 353,542 As of December 31, 2018 Gross Gross Unrealized Unrealized Amortized Cost Gains Losses Fair Value (in thousands) Cash and cash equivalents: Cash and money market funds $ 43,248 $ — $ — $ 43,248 Investment debt securities: Commercial paper 34,353 — (26) 34,327 Corporate debt securities 349,854 27 (704) 349,177 U.S. government and agency securities 9,410 5 (7) 9,408 Total investment debt securities 393,617 32 (737) 392,912 Total cash, cash equivalents and investment debt securities $ 436,865 $ 32 $ (737) $ 436,160

Fixed Assets, Net (Tables)

Fixed Assets, Net (Tables)	3 Months Ended
	Mar. 31, 2019
Fixed Assets, Net [Abstract]
Fixed Assets, Net	Fixed assets are stated at cost and depreciated or amortized using the straight-line method based on useful lives as follows: Useful lives (Years) March 31, 2019 December 31, 2018 (in thousands) Office equipment and software 3 $ 4,051 $ 3,986 Leasehold improvements Over life of lease 10,406 14,464 Furniture and fixtures 7 4,017 3,907 Subtotal 18,474 22,357 Less: accumulated depreciation (11,010) (11,946) Fixed assets, net $ 7,464 $ 10,411

Inventory, Net (Tables)

Inventory, Net (Tables)	3 Months Ended
	Mar. 31, 2019
Inventory, Net [Abstract]
Schedule of Inventory	Inventories are stated at the lower of cost or market. Inventories consisted of the following: March 31, 2019 December 31, 2018 (in thousands) Work-in-process $ 7,224 $ 7,019 Finished goods 146 89 Inventory, net $ 7,370 $ 7,108

Operating Leases (Tables)

Operating Leases (Tables)	3 Months Ended
	Mar. 31, 2019
Operating Leases
Schedule of operating lease assets and liabilities	Operating lease assets and liabilities are classified on the condensed consolidated balance sheets as follows: Leases Classification March 31, 2019 Assets (in thousands) Operating lease assets Other assets $ 12,283 Total leased assets $ 12,283 Liabilities Current Operating lease liabilities Accounts payable, accrued expenses and other liabilities $ 6,701 Noncurrent Operating lease liabilities Long-term other liabilities 9,158 Total lease liabilities $ 15,859
Schedule of operating lease costs	Operating lease costs for the three months ended March 31, 2019 are as follows: Three Months Ended Lease Cost Classification March 31, 2019 (in thousands) Operating lease cost Selling, general and administrative expenses $ 1,678 Short-term lease cost Selling, general and administrative expenses 826 Variable lease cost Selling, general and administrative expenses 224 Sublease income Other income, net (180) Net lease cost $ 2,548
Schedule of maturities of the company’s operating lease liabilities	Maturities of the Company’s operating lease liabilities, which do not include short-term leases, as of March 31, 2019 are as follows: Maturity of Lease Liabilities Operating leases (in thousands) 2019 $ 5,658 2020 6,194 2021 2,879 2022 948 2023 948 Thereafter 395 Total lease payments 17,022 Less: Present value discount (1,163) Total operating lease liabilities $ 15,859

Accounts Payable, Accrued Exp_2

Accounts Payable, Accrued Expenses and Other Liabilities (Tables)	3 Months Ended
	Mar. 31, 2019
Accounts Payable, Accrued Expenses and Other Liabilities [Abstract]
Schedule of Accounts Payable and Accrued Liabilities	Accounts payable, accrued expenses and other liabilities consisted of the following: March 31, 2019 December 31, 2018 (in thousands) Accounts payable $ 18,580 $ 11,765 Accrued employee compensation 11,521 20,335 Accrued contracted services 46,624 54,681 Other liabilities 18,460 18,328 Operating lease liabilities 6,701 — Accounts payable, accrued expenses and other liabilities $ 101,886 $ 105,109

Fair Value Measurements (Tables

Fair Value Measurements (Tables)	3 Months Ended
	Mar. 31, 2019
Fair Value Measurements [Abstract]
Fair Value, Marketable Securities Measured on Recurring and Nonrecurring Basis	Financial assets carried at fair value are classified in the tables below in one of the three categories described above: Fair Value Measurements Using Total Level 1 Level 2 Level 3 (in thousands) March 31, 2019 Assets: Money market funds (included in cash and cash equivalents) $ 40,607 $ 40,607 $ — $ — Available-for-sale debt securities: Commercial paper 8,985 — 8,985 — Corporate debt securities 280,385 — 280,385 — U.S. government and agency securities 9,448 — 9,448 — Total financial assets $ 339,425 $ 40,607 $ 298,818 $ — December 31, 2018 Assets: Money market funds (included in cash and cash equivalents) $ 11,647 $ 11,647 $ — $ — Available-for-sale debt securities: Commercial paper 34,327 — 34,327 — Corporate debt securities 349,177 — 349,177 — U.S. government and agency securities 9,408 — 9,408 — Total financial assets $ 404,559 $ 11,647 $ 392,912 $ —
Schedule of Available for Sale Securities Debt Maturities	The estimated fair value of marketable debt securities (commercial paper, corporate debt securities and U.S. government and agency securities), by contractual maturity, are as follows: Fair Value as of March 31, 2019 December 31, 2018 (in thousands) Due in one year or less $ 269,399 $ 319,717 Due after one year through two years 29,419 73,195 Total investments in debt securities $ 298,818 $ 392,912

Long-Term Debt (Tables)

Long-Term Debt (Tables)	3 Months Ended
	Mar. 31, 2019
Long-Term Debt [Abstract]
Schedule of Long-term Debt Instruments	Debt, net of discounts and deferred financing costs, consisted of the following: March 31, 2019 December 31, 2018 (in thousands) Long-term debt $ 375,351 $ 371,250 Less current portion — — Long-term debt outstanding $ 375,351 $ 371,250

Product Revenue, Net (Tables)

Product Revenue, Net (Tables)	3 Months Ended
	Mar. 31, 2019
Product Revenue, Net [Abstract]
Product Revenues	The table below summarizes consolidated product revenue, net by region: Three Months Ended March 31, 2019 2018 (in thousands) Product revenue, net: U.S. $ 37,991 $ 28,513 ex-U.S. 13,856 6,645 Total product revenue, net $ 51,847 $ 35,158

Stock Compensation (Tables)

Stock Compensation (Tables)	3 Months Ended
	Mar. 31, 2019
Stock Compensation [Abstract]
Schedule of Share Based Compensation Stock Options Activities	The following table summarizes stock option activity during the three months ended March 31, 2019: Weighted Average Number Weighted Remaining Aggregate of Options Average Contractual Intrinsic Value (in thousands) Exercise Price Term (years) (in thousands) Outstanding at December 31, 2018 1,873 $ 97.63 7.5 $ 45,381 Granted 392 $ 110.82 — $ — Exercised (17) $ 54.60 — $ — Cancelled/forfeited (14) $ 86.41 — $ — Expired (10) $ 142.49 — $ — Outstanding at March 31, 2019 2,224 $ 100.15 7.7 $ 57,032 Expected to vest 1,180 $ 93.78 8.9 $ 26,111 Exercisable 1,044 $ 107.35 6.4 $ 30,921
Schedule of Share Based Compensation Arrangement By Share Based Payment Award Grants in Period Fair Value Assumptions	The Company estimated the fair value of stock options granted in the periods presented utilizing a Black-Scholes option-pricing model utilizing the following assumptions: Three Months Ended March 31, 2019 2018 Volatility 87.0 - 87.2 % 60.9 % Expected term (in years) 6.0 6.0 Risk-free rate 2.5 - 2.9 % 2.4 - 2.7 % Expected dividend yield — % — %
Schedule of Share-based Compensation, Restricted Stock Units Award Activity	The following table summarizes the aggregate RSU, restricted stock award (“RSA”), PRSU and performance restricted share award (“PRSA”) activity during the three months ended March 31, 2019: Weighted Number of Average Grant Date Awards Fair Value (in thousands) Non-vested awards at December 31, 2018 773 $ 76.10 Granted 296 $ 116.48 Vested (162) $ 71.62 Forfeited (12) $ 76.68 Non-vested awards at March 31, 2019 895 $ 90.25
Schedule of Stock Based Compensation Expense	Stock-based compensation expense has been reported in the Company’s condensed consolidated statements of operations as follows: Three Months Ended March 31, 2019 2018 (in thousands) Selling, general and administrative $ 11,331 $ 8,676 Research and development 3,566 3,629 Total stock-based compensation $ 14,897 $ 12,305

Net Loss Per Share (Tables)

Net Loss Per Share (Tables)	3 Months Ended
	Mar. 31, 2019
Net loss per common and potential common share:
Schedule of Antidilutive Securities Excluded from Computation of Earnings Per Share	The following potentially dilutive securities have been excluded from the computations of diluted weighted average shares outstanding as of March 31, 2019 and 2018, as the inclusion thereof would have been anti-dilutive: Three Months Ended March 31, 2019 2018 (In thousands) Convertible Notes 2,316 2,316 Options 2,224 2,230 Restricted stock units 645 847 Total 5,185 5,393

Summary of Significant Accoun_3

Summary of Significant Accounting Policies (Narrative) (Details) - USD ($) $ in Thousands	Mar. 31, 2019	Jan. 01, 2019
Operating lease liabilities	$ 15,859
Right of use asset	$ 12,283
Accounting Standards Update 2016-02 [Member] | Restatement Adjustment [Member]
Operating lease liabilities		$ 25,400
Right of use asset		$ 19,600

Significant Agreements (Narrati

Significant Agreements (Narrative) (Details) - USD ($) $ in Thousands	1 Months Ended		3 Months Ended		12 Months Ended
	May 31, 2014	Mar. 31, 2011	Mar. 31, 2019	Mar. 31, 2018	Dec. 31, 2018
Significant Agreements [Line Items]
Revenue			$ 52,252	$ 35,963
License [Member]
Significant Agreements [Line Items]
Revenue			405	805
Product [Member]
Significant Agreements [Line Items]
Revenue			51,847	35,158
Milestone Payment [Member] | Dainippon Sumitomo Pharma Co Ltd [Member]
Significant Agreements [Line Items]
License arrangement, deferred revenue, recognized			2,000		$ 2,400
Nonsoftware License Arrangement [Member] | Dainippon Sumitomo Pharma Co Ltd [Member]
Significant Agreements [Line Items]
Development milestone reached			6,000
Nonsoftware License Arrangement [Member] | Intellectual Property [Member] | License [Member]
Significant Agreements [Line Items]
Revenue			400	800
Nonsoftware License Arrangement [Member] | Up-front Payment [Member] | Dainippon Sumitomo Pharma Co Ltd [Member]
Significant Agreements [Line Items]
License agreement payment		$ 15,000
Nonsoftware License Arrangement [Member] | Additional Development Receivable [Member] | Dainippon Sumitomo Pharma Co Ltd [Member]
Significant Agreements [Line Items]
Contingent arrangement receivable amount			$ 23,000
Sumitomo Amendment [Member]
Significant Agreements [Line Items]
License arrangement, deferred revenue, recognized				$ 400
Korea [Member] | Nonsoftware License Arrangement [Member] | Up-front Payment [Member] | Dainippon Sumitomo Pharma Co Ltd [Member]
Significant Agreements [Line Items]
License agreement payment	$ 1,000

Cash, Cash Equivalents and In_3

Cash, Cash Equivalents and Investment Debt Securities (Cash, Cash Equivalents and Investment Debt Securities) (Details) - USD ($) $ in Thousands	Mar. 31, 2019	Dec. 31, 2018
Investment Debt Securities Abstract
Total investments, Amortized Cost	$ 298,716	$ 393,617
Total cash and cash equivalents and investment debt securities, Amortized Cost	353,440	436,865
Total investments, Gross Unrealized Gains	233	32
Total cash and cash equivalents and investment debt securities, Gross Unrealized Gains	233	32
Total investments, Gross Unrealized Losses	(131)	(737)
Total cash and cash equivalents and investment debt securities, Gross Unrealized Losses	(131)	(737)
Total investments, Fair Value	298,818	392,912
Total cash and cash equivalents and investment debt securities, Fair Value	353,542	436,160
Commercial Paper [Member]
Investment Debt Securities Abstract
Total investments, Amortized Cost	8,987	34,353
Total investments, Gross Unrealized Losses	(2)	(26)
Total investments, Fair Value	8,985	34,327
Corporate Debt Securities [Member]
Investment Debt Securities Abstract
Total investments, Amortized Cost	280,291	349,854
Total investments, Gross Unrealized Gains	221	27
Total investments, Gross Unrealized Losses	(127)	(704)
Total investments, Fair Value	280,385	349,177
US Government Agencies Debt Securities [Member]
Investment Debt Securities Abstract
Total investments, Amortized Cost	9,438	9,410
Total investments, Gross Unrealized Gains	12	5
Total investments, Gross Unrealized Losses	(2)	(7)
Total investments, Fair Value	9,448	9,408
Cash and Money Market Funds [Member]
Cash and cash equivalents:
Cash and Cash Equivalents, Amortized Cost	54,724	43,248
Cash and cash equivalents, Fair Value	$ 54,724	$ 43,248

Cash, Cash Equivalents, and Inv

Cash, Cash Equivalents, and Investment Debt Securities (Narrative) (Details)	Mar. 31, 2019security
Cash, Cash Equivalents, and Investment Debt Securities [Abstract]
Number of positions that were in a continuous unrealized loss position for more than twelve months	20

Fixed Assets, Net (Fixed Assets

Fixed Assets, Net (Fixed Assets Stated at Cost) (Details) - USD ($) $ in Thousands	3 Months Ended
	Mar. 31, 2019	Dec. 31, 2018
Fixed assets	$ 18,474	$ 22,357
Less: accumulated depreciation	(11,010)	(11,946)
Fixed assets, net	7,464	10,411
Office Equipment [Member]
Fixed assets	$ 4,051	3,986
Property, Plant and Equipment, Useful Life	3 years
Leasehold Improvements [Member]
Fixed assets	$ 10,406	14,464
Property, Plant and Equipment, Estimated Useful Lives	Over life of lease
Furniture and Fixtures [Member]
Fixed assets	$ 4,017	$ 3,907
Property, Plant and Equipment, Useful Life	7 years

Inventory (Schedule of Inventor

Inventory (Schedule of Inventory) (Details) - USD ($) $ in Thousands	Mar. 31, 2019	Dec. 31, 2018
Inventory, Net [Abstract]
Work-in-process	$ 7,224	$ 7,019
Finished goods	146	89
Inventory, net	$ 7,370	$ 7,108

Operating Leases (Details)

Operating Leases (Details)	3 Months Ended
	Mar. 31, 2019
Operating Leases
Operating lease, existence of option to extend	true

Operating Leases (Assets and Li

Operating Leases (Assets and Liabilities) (Details) $ in Thousands	Mar. 31, 2019USD ($)
Operating Leases
Operating lease assets	$ 12,283
Other assets	us-gaap:OtherAssetsNoncurrent
Total leased assets	$ 12,283
Operating lease liabilities, current	$ 6,701
Accounts payable, accrued expenses and other liabilities	us-gaap:AccountsPayableAndOtherAccruedLiabilities
Operating lease liabilities, Noncurrent	$ 9,158
Long-term other liabilities	us-gaap:LongTermDebtNoncurrent
Total lease liabilities	$ 15,859

Operating Leases (Lease Cost, T

Operating Leases (Lease Cost, Term and Discount Rate) (Details) $ in Thousands	3 Months Ended
	Mar. 31, 2019USD ($)
Lease Cost
Net lease cost	$ 2,548
Operating leases, weighted-average remaining term	2 years 10 months 24 days
Operating leases, weighted-average discount rate	5.00%
Selling, general and administrative expenses
Lease Cost
Operating lease cost	$ 1,678
Short-term lease cost	826
Variable lease cost	224
Other income, net
Lease Cost
Sublease income	$ (180)

Operating Leases (Maturities of

Operating Leases (Maturities of Operating Lease Liabilities and lease payments) (Details) $ in Thousands	3 Months Ended
	Mar. 31, 2019USD ($)
Maturity of Lease Liabilities
2019	$ 5,658
2020	6,194
2021	2,879
2022	948
2023	948
Thereafter	395
Total lease payments	17,022
Less: Present value discount	(1,163)
Operating lease liabilities	15,859
Cash payments included in the measurement of the Company’s lease liabilities	$ 1,900

Accounts Payable, Accrued Exp_3

Accounts Payable, Accrued Expenses and Other Liabilities (Schedule of Accounts Payable and Accrued Liabilities) (Details) - USD ($) $ in Thousands	Mar. 31, 2019	Dec. 31, 2018
Accounts Payable, Accrued Expenses and Other Liabilities [Abstract]
Accounts payable	$ 18,580	$ 11,765
Accrued employee compensation	11,521	20,335
Accrued contracted services	46,624	54,681
Other liabilities	18,460	18,328
Operating lease liabilities	6,701
Accounts payable, accrued expenses and other liabilities	$ 101,886	$ 105,109

Fair Value Measurements (Fair V

Fair Value Measurements (Fair Value, Marketable Securities Measured on Recurring and Nonrecurring Basis) (Details) - USD ($) $ in Thousands	Mar. 31, 2019	Dec. 31, 2018
Available-For-Sale Securities, Fair Value Disclosure	$ 298,818	$ 392,912
Total financial assets	339,425	404,559
Fair Value, Inputs, Level 1 [Member]
Total financial assets	40,607	11,647
Fair Value, Inputs, Level 2 [Member]
Total financial assets	298,818	392,912
Money Market Funds [Member]
Cash and cash equivalents, fair value disclosure	40,607	11,647
Money Market Funds [Member] | Fair Value, Inputs, Level 1 [Member]
Cash and cash equivalents, fair value disclosure	40,607	11,647
Commercial Paper [Member]
Available-For-Sale Securities, Fair Value Disclosure	8,985	34,327
Commercial Paper [Member] | Fair Value, Inputs, Level 2 [Member]
Available-For-Sale Securities, Fair Value Disclosure	8,985	34,327
Corporate Debt Securities [Member]
Available-For-Sale Securities, Fair Value Disclosure	280,385	349,177
Corporate Debt Securities [Member] | Fair Value, Inputs, Level 2 [Member]
Available-For-Sale Securities, Fair Value Disclosure	280,385	349,177
US Government Agencies Debt Securities [Member]
Available-For-Sale Securities, Fair Value Disclosure	9,448	9,408
US Government Agencies Debt Securities [Member] | Fair Value, Inputs, Level 2 [Member]
Available-For-Sale Securities, Fair Value Disclosure	$ 9,448	$ 9,408

Fair Value Measurements (Schedu

Fair Value Measurements (Schedule of Available for Sale Securities Debt Maturities) (Details) - USD ($) $ in Thousands	Mar. 31, 2019	Dec. 31, 2018
Fair Value Measurements [Abstract]
Due in one year or less	$ 269,399	$ 319,717
Due after one year through two years	29,419	73,195
Total investments in debt securities	$ 298,818	$ 392,912

Long-Term Debt (Narrative) (Det

Long-Term Debt (Narrative) (Details) $ / shares in Units, $ in Thousands	Jul. 06, 2016USD ($)$ / shares	Mar. 31, 2019USD ($)item	Mar. 31, 2018USD ($)	Dec. 31, 2018USD ($)	Jun. 30, 2016$ / shares
Payments for capped call transactions and associated costs	$ 38,400
Cap price of capped call transaction | $ / shares					$ 262.2725
Long-term debt		$ 375,351		$ 371,250
Interest expense		$ 7,839	$ 7,509
Convertible Senior Notes 3.25% [Member] | Convertible Debt [Member]
Debt instrument, face amount	460,000
Debt instrument, interest rate, stated percentage		3.25%
Proceeds from convertible debt	447,600
Debt issuance costs	$ 12,400	$ 8,400
Debt instrument convertible, percentage of conversion price		130.00%
Average percentage of closing sale price of common stock		98.00%
Debt instrument, convertible, conversion ratio	5.0358
Debt instrument, convertible, conversion price | $ / shares	$ 198.58
Percentage of repurchase price is equal to principal amount of convertible notes		100.00%
Debt instrument liability component effective interest rate		8.40%
Long-term debt		$ 334,400
Debt instrument, unamortized discount, noncurrent		113,100
Interest expense		7,800	$ 7,500
Interest payable, current		3,700		$ 7,500
Convertible debt, outstanding		$ 460,000
Convertible Senior Notes 3.25% [Member] | Convertible Debt [Member] | One Hundred Thirty Percent Applicable Conversion Price [Member] | Maximum [Member]
Debt instrument convertible consecutive trading days		30
Convertible Senior Notes 3.25% [Member] | Convertible Debt [Member] | One Hundred Thirty Percent Applicable Conversion Price [Member] | Minimum [Member]
Debt instrument convertible consecutive trading days		20
Convertible Senior Notes 3.25% [Member] | Convertible Debt [Member] | Ninety Eight Percent Applicable Conversion Price [Member]
Debt instrument convertible consecutive trading days | item		5

Long-Term Debt (Schedule of Lon

Long-Term Debt (Schedule of Long-term Debt Instruments) (Details) - USD ($) $ in Thousands	Mar. 31, 2019	Dec. 31, 2018
Long-Term Debt [Abstract]
Long-term Debt, Total	$ 375,351	$ 371,250
Less current portion
Long-term debt outstanding	$ 375,351	$ 371,250

Product Revenue, Net (Narrative

Product Revenue, Net (Narrative) (Details) - USD ($) $ in Thousands	3 Months Ended
	Mar. 31, 2019	Mar. 31, 2018
Product revenue, net	$ 52,252	$ 35,963
Product [Member]
Product revenue, net	$ 51,847	$ 35,158

Product Revenue, Net (Schedule

Product Revenue, Net (Schedule of Product Revenue, Net) (Details) - USD ($) $ in Thousands	3 Months Ended
	Mar. 31, 2019	Mar. 31, 2018
Revenue Recognition, Multiple-deliverable Arrangements [Line Items]
Product revenue, net	$ 52,252	$ 35,963
United States [Member]
Revenue Recognition, Multiple-deliverable Arrangements [Line Items]
Product revenue, net	37,991	28,513
Non-US [Member]
Revenue Recognition, Multiple-deliverable Arrangements [Line Items]
Product revenue, net	13,856	6,645
Product [Member]
Revenue Recognition, Multiple-deliverable Arrangements [Line Items]
Product revenue, net	$ 51,847	$ 35,158

Stockholders' (Deficit) Equity

Stockholders' (Deficit) Equity (Narrative) (Details)	Apr. 09, 2018$ / sharesshares
Stock issued during period, shares, new issues	2,695,313
Shares issued, price per share | $ / shares	$ 64
Private Placement [Member]
Stock issued during period, shares, new issues	1,562,500
Underwriters [Member]
Stock issued during period, shares, new issues	351,563

Stock Compensation (Narrative)

Stock Compensation (Narrative) (Details) - USD ($) $ in Thousands	Jan. 01, 2019	Oct. 31, 2012	Mar. 31, 2019	Mar. 31, 2018
Value of stock options exercised			$ 943	$ 481
2012 Stock Plan [Member]
Additional shares available	1,187,599	555,843
Stock Options [Member]
Share-based compensation not yet recognized, options			$ 63,100
Share-based compensation not yet recognized, period			1 year 6 months
Performance Stock Units (PSUs) [Member]
Shares granted during period for stock based compensation			57,800
Performance Stock Units and Awards [Member]
Performance period			3 years
Share based compensation expenses			$ 700
Performance Stock Units and Awards [Member] | Minimum [Member]
Payout percentage, as percent of target award			0.00%
Performance Stock Units and Awards [Member] | Maximum [Member]
Payout percentage, as percent of target award			150.00%
Restricted and Performance Stock Units and Awards [Member]
Share-based compensation not yet recognized, other than options			$ 69,800
Share-based compensation not yet recognized, period			1 year 7 months 6 days

Stock Compensation (Schedule of

Stock Compensation (Schedule of Share Based Compensation Stock Options Activities) (Details) - USD ($) $ / shares in Units, shares in Thousands, $ in Thousands	3 Months Ended	12 Months Ended
	Mar. 31, 2019	Dec. 31, 2018
Stock Compensation [Abstract]
Beginning Outstanding, Number of Shares	1,873
Granted - Number of Shares	392
Exercised - Number of Shares	(17)
Forfeited - Number of Shares	(14)
Expired - Number of Shares	(10)
Ending Outstanding, Number of Shares	2,224	1,873
Expected to vest - Number of shares	1,180
Exercisable - Number of Shares	1,044
Beginning Outstanding, Weighted Average Exercise Price	$ 97.63
Granted - Weighted Average Exercise Price	110.82
Exercised - Weighted Average Exercise Price	54.60
Forfeited - Weighted Average Exercise Price	86.41
Expired - Weighted Average Exercise Price	142.49
Ending Outstanding, Weighted Average Exercise Price	100.15	$ 97.63
Expected to vest - Weighted Average Exercise Price	93.78
Exercisable - Weighted Average Exercise Price	$ 107.35
Options Outstanding - Weighted Average Remaining Life	7 years 8 months 12 days	7 years 6 months
Expected to vest - Weighted Average Remaining Term	8 years 10 months 24 days
Exercisable - Weighted Average Remaining Term	6 years 4 months 24 days
Options Outstanding - Aggregate Intrinsic Value	$ 57,032	$ 45,381
Expected to vest - Aggregate Intrinsic Value	26,111
Exercisable - Aggregate Intrinsic Value	$ 30,921

Stock Compensation (Schedule _2

Stock Compensation (Schedule of Share Based Compensation Arrangement By Share Based Payment Award Grants in Period Fair Value Assumptions) (Details) - Stock Options [Member]	3 Months Ended
	Mar. 31, 2019	Mar. 31, 2018
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Volatility		60.90%
Volatility, minimum	87.00%
Volatility, maximum	87.20%
Expected term (in years)	6 years	6 years
Risk-free interest rate, minimum	2.50%	2.40%
Risk-free interest rate, maximum	2.90%	2.70%

Stock Compensation (Schedule _3

Stock Compensation (Schedule of Share-based Compensation, Restricted Stock Units and Award Activity) (Details) shares in Thousands	3 Months Ended
	Mar. 31, 2019$ / sharesshares
Stock Compensation [Abstract]
Outstanding, December 31, 2018 | shares	773
Granted - Shares | shares	296
Vested - Shares | shares	(162)
Forfeited - Shares | shares	(12)
Outstanding, March 31, 2019 | shares	895
Outstanding - Weighted Average Fair Value, December 31, 2018 | $ / shares	$ 76.10
Granted - Weighted Average Fair Value | $ / shares	116.48
Vested - Weighted Average Fair Value | $ / shares	71.62
Forfeited - Weighted Average Fair Value | $ / shares	76.68
Outstanding - Weighted Average Fair Value, March 31, 2019 | $ / shares	$ 90.25

Stock Compensation (Schedule _4

Stock Compensation (Schedule of Stock Based Compensation Expense) (Details) - USD ($) $ in Thousands	3 Months Ended
	Mar. 31, 2019	Mar. 31, 2018
Employee Service Share-based Compensation, Allocation of Recognized Period Costs [Line Items]
Allocated stock-based compensation	$ 14,897	$ 12,305
Selling, general and administrative expenses
Employee Service Share-based Compensation, Allocation of Recognized Period Costs [Line Items]
Allocated stock-based compensation	11,331	8,676
Research and Development Expense
Employee Service Share-based Compensation, Allocation of Recognized Period Costs [Line Items]
Allocated stock-based compensation	$ 3,566	$ 3,629

Net Loss Per Share (Schedule of

Net Loss Per Share (Schedule of Antidilutive Securities Excluded from Computation of Earnings Per Share) (Details) - shares shares in Thousands	3 Months Ended
	Mar. 31, 2019	Mar. 31, 2018
Antidilutive securities excluded from computation of earnings per share, amount	5,185	5,393
Convertible Notes [Member]
Antidilutive securities excluded from computation of earnings per share, amount	2,316	2,316
Stock Options [Member]
Antidilutive securities excluded from computation of earnings per share, amount	2,224	2,230
Restricted Stock Units (RSUs) [Member]
Antidilutive securities excluded from computation of earnings per share, amount	645	847