Intercept Pharmaceuticals (ICPT) 10-Q 6 May 21 2021 Q1 Quarterly report Financial data

Document And Entity Information

Document And Entity Information	3 Months Ended
	Mar. 31, 2021shares
Document and Entity Information [Abstract]
Document Type	10-Q
Document Quarterly Report	true
Document Transition Report	false
Document Period End Date	Mar. 31, 2021
Entity File Number	001-35668
Entity Registrant Name	INTERCEPT PHARMACEUTICALS, INC.
Entity Incorporation, State or Country Code	DE
Entity Tax Identification Number	22-3868459
Entity Address, Address Line One	10 Hudson Yards, 37th Floor
Entity Address, City or Town	New York
Entity Address, State or Province	NY
Entity Address, Postal Zip Code	10001
City Area Code	646
Local Phone Number	747-1000
Title of 12(b) Security	Common Stock
Trading Symbol	ICPT
Security Exchange Name	NASDAQ
Entity Current Reporting Status	Yes
Entity Interactive Data Current	Yes
Entity Filer Category	Large Accelerated Filer
Entity Small Business	false
Entity Emerging Growth Company	false
Entity Shell Company	false
Entity Common Stock, Shares Outstanding	33,154,107
Entity Central Index Key	0001270073
Current Fiscal Year End Date	--12-31
Document Fiscal Period Focus	Q1
Document Fiscal Year Focus	2021
Amendment Flag	false

Condensed Consolidated Balance

Condensed Consolidated Balance Sheets - USD ($) $ in Thousands	Mar. 31, 2021	Dec. 31, 2020
Current assets:
Cash and cash equivalents	$ 92,946	$ 58,151
Restricted cash	7,433	7,503
Investment debt securities, available-for-sale	318,237	411,516
Accounts receivable, net of allowance for credit losses of $198 and $235, respectively	42,594	41,549
Prepaid expenses and other current assets	26,353	27,022
Total current assets	487,563	545,741
Fixed assets, net	5,487	6,326
Inventory	8,992	9,027
Security deposits	6,908	7,068
Other assets	11,161	12,327
Total assets	520,111	580,489
Current liabilities:
Accounts payable, accrued expenses and other liabilities	140,783	171,039
Short-term interest payable	5,450	8,037
Total current liabilities	146,233	179,076
Long-term liabilities:
Long-term debt	568,114	560,582
Long-term other liabilities	5,762	7,684
Total liabilities	720,109	747,342
Commitments and contingencies (Note 15)
Stockholders' deficit:
Common stock par value $0.001 per share; 90,000,000 shares authorized; 33,154,107 and 33,015,614 shares issued and outstanding as of March 31, 2021 and December 31, 2020, respectively	33	33
Additional paid-in capital	2,241,273	2,233,937
Accumulated other comprehensive loss, net	(2,538)	(2,477)
Accumulated deficit	(2,438,766)	(2,398,346)
Total stockholders' deficit	(199,998)	(166,853)
Total liabilities and stockholders' deficit	$ 520,111	$ 580,489

Condensed Consolidated Balanc_2

Condensed Consolidated Balance Sheets (Parenthetical) - USD ($) $ in Thousands	Mar. 31, 2021	Dec. 31, 2020
Condensed Consolidated Balance Sheets
Allowance for credit losses	$ 198	$ 235
Common stock, par value (in dollars per share)	$ 0.001	$ 0.001
Common stock, authorized	90,000,000	90,000,000
Common stock, shares, issued	33,154,107	33,015,614
Common stock, shares, outstanding	33,154,107	33,015,614

Condensed Consolidated Statemen

Condensed Consolidated Statements of Operations - USD ($) shares in Thousands, $ in Thousands	3 Months Ended
	Mar. 31, 2021	Mar. 31, 2020
Revenue	$ 81,661	$ 72,652
Operating expenses:
Cost of sales	810	852
Selling, general and administrative	59,271	98,558
Research and development	50,766	56,687
Restructuring	161	0
Total operating expenses	111,008	156,097
Operating loss	(29,347)	(83,445)
Other income (expense):
Interest expense	(12,419)	(11,777)
Other income, net	1,346	2,239
Total other (expense), net	(11,073)	(9,538)
Net loss	$ (40,420)	$ (92,983)
Net loss per common and potential common share:
Basic and diluted	$ (1.22)	$ (2.86)
Weighted average common and potential common shares outstanding:
Basic and diluted	33,139	32,561
Product [Member]
Revenue	$ 81,661	$ 72,652

Condensed Consolidated Statem_2

Condensed Consolidated Statements of Comprehensive Loss - USD ($) $ in Thousands	3 Months Ended
	Mar. 31, 2021	Mar. 31, 2020
Condensed Consolidated Statements of Comprehensive Loss
Net loss	$ (40,420)	$ (92,983)
Net changes related to available-for-sale investment debt securities:
Unrealized losses on investment debt securities	(344)	(2,163)
Reclassification adjustment for realized gains on investment debt securities included in other income, net	2	9
Net unrealized losses on investment debt securities	(342)	(2,154)
Foreign currency translation gains (losses)	281	(512)
Other comprehensive loss	(61)	(2,666)
Comprehensive loss	$ (40,481)	$ (95,649)

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]	Accumulated (Deficit) Equity [Member]	Total
Balance at Dec. 31, 2019	$ 33	$ 2,176,133	$ (1,144)	$ (2,123,466)	$ 51,556
Balance (in shares) at Dec. 31, 2019	32,853
Stock-based compensation	$ 0	12,473	0	0	12,473
Net proceeds from exercise of stock options	$ 0	(1,783)	0	0	(1,783)
Net proceeds from exercise of stock options (in shares)	88
Employee withholding taxes related to stock-based awards	$ 0	(1,322)	0	0	(1,322)
Employee withholding taxes related to stock-based awards, (in shares)	(4)
Other comprehensive income (loss)	$ 0	0	(2,660)	0	(2,660)
Net loss	0	0	0	(92,983)	(92,983)
Balance at Mar. 31, 2020	$ 33	2,185,501	(3,804)	(2,216,449)	(34,719)
Balance (in shares) at Mar. 31, 2020	32,937
Balance at Dec. 31, 2020	$ 33	2,233,937	(2,477)	(2,398,346)	(166,853)
Balance (in shares) at Dec. 31, 2020	33,016
Stock-based compensation	$ 0	8,419	0	0	8,419
Net proceeds from exercise of stock options	$ 0	0	0	0	$ 0
Net proceeds from exercise of stock options (in shares)	141				0
Employee withholding taxes related to stock-based awards	$ 0	(1,083)	0	0	$ (1,083)
Employee withholding taxes related to stock-based awards, (in shares)	(3)
Other comprehensive income (loss)	$ 0	0	(61)	0	(61)
Net loss	0	0	0	(40,420)	(40,420)
Balance at Mar. 31, 2021	$ 33	$ 2,241,273	$ (2,538)	$ (2,438,766)	$ (199,998)
Balance (in shares) at Mar. 31, 2021	33,154

Condensed Consolidated Statem_4

Condensed Consolidated Statements of Cash Flows - USD ($) $ in Thousands	3 Months Ended
	Mar. 31, 2021	Mar. 31, 2020
Cash flows from operating activities:
Net loss	$ (40,420)	$ (92,983)
Adjustments to reconcile net loss to net cash used in operating activities:
Stock-based compensation	8,419	12,473
Amortization of premium on investment debt securities	1,220	536
Amortization of deferred financing costs	671	614
Depreciation	870	764
Non-cash operating lease cost	1,509	1,584
Accretion of debt discount	6,861	6,276
Provision for allowance of credit losses, net of write-offs	198	179
Changes in operating assets:
Accounts receivable	(1,408)	(6,549)
Prepaid expenses and other current assets	547	(7,122)
Inventory	86	(2,377)
Security deposits	95	50
Changes in operating liabilities:
Accounts payable, accrued expenses and other current liabilities	(29,286)	(7,899)
Operating lease liabilities	(1,425)	(1,690)
Interest payable	(2,587)	(2,587)
Net cash used in operating activities	(54,650)	(98,731)
Cash flows from investing activities:
Purchases of investment debt securities	(50,533)	(34,444)
Sales and maturities of investment debt securities	142,250	106,693
Purchases of equipment, leasehold improvements, and furniture and fixtures	(377)	(432)
Net cash provided by investing activities	91,340	71,817
Cash flows from financing activities:
Proceeds from exercise of options, net	0	569
Payments of employee withholding taxes related to stock-based awards	(1,083)	(1,322)
Net cash used in financing activities	(1,083)	(753)
Effect of exchange rate changes on cash, cash equivalents and restricted cash	(882)	(694)
Net increase (decrease) in cash, cash equivalents and restricted cash	34,725	(28,361)
Cash, cash equivalents and restricted cash at beginning of period	65,654	74,780
Cash, cash equivalents and restricted cash at end of period	$ 100,379	$ 46,419

Condensed Consolidated Statem_5

Condensed Consolidated Statements of Cash Flows (Parenthetical) - USD ($) $ in Thousands	3 Months Ended
	Mar. 31, 2021	Mar. 31, 2020
Supplemental disclosure of non-cash transactions:
Right-of-use asset obtained in exchange for new operating lease obligations	$ 0	$ 1,006
Non-cash investing and financing activities
Net decrease in accrued fixed assets	(348)	0
Reconciliation of cash, cash equivalents and restricted cash included in the consolidated balance sheets:
Cash and cash equivalents	92,946	41,408
Restricted cash	7,433	5,011
Total cash, cash equivalents and restricted cash	$ 100,379	$ 46,419

Overview of Business

Overview of Business	3 Months Ended
	Mar. 31, 2021
Basis of Presentation [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, 2021
Basis of Presentation [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 U.S. Securities and Exchange Commission (“SEC”). Operating results for the three months ended March 31, 2021 are not necessarily indicative of the results that may be expected for any future period or for the year ending December 31, 2021. 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, 2020, included in the Company’s Annual Report on Form 10-K for the year ended December 31, 2020 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. ​ We are not presently aware of any events or circumstances arising from the coronavirus (“COVID-19”) pandemic that would require us to update our estimates or judgments or revise the carrying value of our assets or liabilities. ​

Summary of Significant Accounti

Summary of Significant Accounting Policies	3 Months Ended
	Mar. 31, 2021
Summary of Significant Accounting Policiies
Summary of Significant Accounting Policies	3. Summary of Significant Accounting Policies ​ Recent Accounting Pronouncements Recently Adopted Accounting Pronouncements In December 2019, the Financial Accounting Standards Board (“FASB”) issued Accounting Standards Update (“ASU”) No. 2019-12, “Income Taxes (Topic 740): Simplifying the Accounting for Income Taxes (“ASU 2019-12”), which is intended to simplify various aspects related to accounting for income taxes. ASU 2019-12 removes certain exceptions to the general principles in Topic 740 and also clarifies and amends existing guidance to improve consistent application. This guidance is effective for fiscal years, and interim periods within those fiscal years, beginning after December 15, 2020, with early adoption permitted. The Company adopted ASU 2019-12 on January 1, 2021 and its adoption did not have any material impact on the Company’s condensed consolidated financial statements and related disclosures. ​ Recent Accounting Pronouncements to be Adopted In August 2020, the FASB issued ASU No. 2020-06, “Debt—Debt with Conversion and Other Options (Subtopic 470-20) and Derivatives and Hedging—Contracts in Entity’s Own Equity (Subtopic 815-40): Accounting for Convertible Instruments and Contracts in an Entity’s Own Equity (“ASU 2020-06”), which simplifies accounting for convertible instruments by removing major separation models required under current U.S. GAAP. The ASU removes certain settlement conditions that are required for equity contracts to qualify for the derivative scope exception and it also simplifies the diluted earnings per share calculation in certain areas. Either a modified retrospective method of transition or a fully retrospective method of transition is permissible for the adoption of this standard. This guidance is effective for fiscal years, and interim periods within those fiscal years, beginning after December 15, 2021, with early adoption permitted. The Company expects the impact of this standard to be material on its consolidated financial statements and related disclosures .

Cash, Cash Equivalents and Inve

Cash, Cash Equivalents and Investment Debt Securities	3 Months Ended
	Mar. 31, 2021
Cash, Cash Equivalents, and Investment Debt Securities [Abstract]
Cash, Cash Equivalents, and Investment Debt Securities	4. 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, 2021 and December 31, 2020: ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ As of March 31, 2021 ​ ​ ​ ​ ​ Allowance ​ Gross ​ Gross ​ ​ ​ ​ ​ ​ ​ ​ for Credit ​ Unrealized ​ Unrealized ​ ​ ​ ​ Amortized Cost ​ Losses Gains Losses Fair Value ​ ​ (in thousands) Cash and cash equivalents: ​ ​ ​ ​ ​ ​ ​ Cash and money market funds ​ $ 85,946 ​ $ — ​ $ — ​ $ — ​ $ 85,946 Commercial paper ​ ​ 2,000 ​ ​ — ​ ​ — ​ ​ — ​ ​ 2,000 U.S. treasuries ​ ​ 5,000 ​ ​ — ​ ​ — ​ ​ — ​ ​ 5,000 Total cash and cash equivalents ​ ​ 92,946 ​ ​ — ​ ​ — ​ ​ — ​ ​ 92,946 Investment debt securities: ​ ​ ​ ​ ​ Commercial paper ​ 57,676 ​ — ​ 5 ​ (6) ​ 57,675 Corporate debt securities ​ 260,444 ​ — ​ 195 ​ (77) ​ 260,562 Total investment debt securities ​ 318,120 ​ — ​ 200 ​ (83) ​ 318,237 Total cash, cash equivalents and investment debt securities ​ $ 411,066 ​ $ — ​ $ 200 ​ $ (83) ​ $ 411,183 ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ As of December 31, 2020 ​ ​ ​ ​ ​ Allowance ​ Gross ​ Gross ​ ​ ​ ​ ​ ​ ​ ​ for Credit ​ Unrealized ​ Unrealized ​ ​ ​ ​ Amortized Cost ​ Losses Gains Losses ​ Fair Value ​ ​ (in thousands) ​ ​ ​ Cash and cash equivalents: ​ ​ ​ ​ ​ ​ ​ ​ Cash and money market funds ​ $ 58,151 ​ $ — ​ $ — ​ $ — ​ $ 58,151 Total cash and cash equivalents ​ ​ 58,151 ​ ​ — ​ ​ — ​ ​ — ​ ​ 58,151 Investment debt securities: ​ ​ ​ ​ ​ Commercial paper ​ 55,460 ​ — ​ 6 ​ (9) ​ 55,457 Corporate debt securities ​ 355,597 ​ — ​ 529 ​ (67) ​ 356,059 Total investment debt securities ​ 411,057 ​ — ​ 535 ​ (76) ​ 411,516 Total cash, cash equivalents and investment debt securities ​ $ 469,208 ​ $ — ​ $ 535 ​ $ (76) ​ $ 469,667 ​ The aggregate fair value of the Company’s available-for-sale investment debt securities that have been in a continuous unrealized loss position for less than twelve months or twelve months or longer is as follows: ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ As of March 31, 2021 ​ ​ Less than 12 months ​ 12 months or longer ​ Total ​ ​ (in thousands) ​ ​ ​ ​ ​ Gross ​ ​ ​ ​ Gross ​ ​ ​ ​ Gross ​ ​ ​ ​ ​ Unrealized ​ ​ ​ Unrealized ​ ​ ​ ​ Unrealized ​ Fair Value Losses Fair Value Losses Fair Value Losses Commercial paper ​ $ 23,184 ​ $ (6) ​ $ — ​ $ — ​ $ 23,184 ​ $ (6) Corporate debt securities ​ ​ 131,758 ​ ​ (77) ​ ​ — ​ ​ — ​ ​ 131,758 ​ ​ (77) Total ​ $ 154,942 ​ $ (83) ​ $ — ​ $ — ​ $ 154,942 ​ $ (83) ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ As of December 31, 2020 ​ ​ Less than 12 months ​ 12 months or longer ​ Total ​ ​ (in thousands) ​ ​ ​ ​ Gross ​ ​ Gross ​ ​ Gross ​ ​ ​ ​ ​ Unrealized ​ ​ ​ ​ Unrealized ​ ​ ​ ​ Unrealized ​ Fair Value Losses Fair Value Losses Fair Value Losses Commercial paper ​ $ 32,970 ​ $ (9) ​ $ — ​ $ — ​ $ 32,970 ​ $ (9) Corporate debt securities ​ 143,076 ​ (67) ​ — ​ — ​ 143,076 ​ (67) Total ​ $ 176,046 ​ $ (76) ​ $ — ​ $ — ​ $ 176,046 ​ $ (76) ​ ​

Fair Value Measurements

Fair Value Measurements	3 Months Ended
	Mar. 31, 2021
Fair Value Measurements [Abstract]
Fair Value Measurements	5. 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 money market funds are classified within Level 1 of the fair value hierarchy because they are valued using quoted prices in active markets. Investment debt securities 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, 2021 ​ ​ ​ ​ Assets ​ ​ ​ ​ Cash and cash equivalents: ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Money market funds ​ $ 64,204 ​ $ 64,204 ​ $ — ​ $ — Commercial paper ​ ​ 2,000 ​ ​ — ​ ​ 2,000 ​ ​ — U.S. treasuries ​ ​ 5,000 ​ ​ 5,000 ​ ​ — ​ ​ — Available-for-sale investment debt securities: ​ ​ ​ ​ ​ Commercial paper ​ 57,675 ​ — ​ 57,675 ​ — Corporate debt securities ​ 260,562 ​ — ​ 260,562 ​ — Total financial assets ​ $ 389,441 ​ $ 69,204 ​ $ 320,237 ​ $ — ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ December 31, 2020 ​ ​ ​ ​ Assets ​ ​ ​ ​ Cash and cash equivalents: ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Money market funds ​ $ 15,492 ​ $ 15,492 ​ $ — ​ $ — Available-for-sale investment debt securities: ​ ​ ​ ​ Commercial paper ​ 55,457 ​ — ​ 55,457 ​ — Corporate debt securities ​ 356,059 ​ — ​ 356,059 ​ — Total financial assets ​ $ 427,008 ​ $ 15,492 ​ $ 411,516 ​ $ — ​ See Note 10 for the carrying amount and estimated fair value of our and The aggregate fair value of all available-for-sale investment debt securities (commercial paper and corporate debt securities), by contractual maturity, are as follows: ​ ​ ​ ​ ​ ​ ​ ​ ​ Fair Value as of ​ March 31, 2021 December 31, 2020 ​ ​ (in thousands) Due in one year or less ​ $ 285,229 ​ $ 328,077 Due after one year through two years ​ 33,008 ​ 83,439 Total investment debt securities ​ $ 318,237 ​ $ 411,516 ​ Actual maturities may differ from contractual maturities because issuers may have the right to call or prepay obligations without call or prepayment penalties.

Fixed Assets, Net

Fixed Assets, Net	3 Months Ended
	Mar. 31, 2021
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, 2021 December 31, 2020 ​ ​ ​ ​ (in thousands) Office equipment and software 3 ​ $ 5,369 ​ $ 5,364 Leasehold improvements Shorter of remaining lease term or useful life ​ 13,269 ​ 13,237 Furniture and fixtures 7 ​ 4,608 ​ 4,602 Subtotal ​ ​ ​ 23,246 ​ 23,203 Less: accumulated depreciation ​ ​ ​ (17,759) ​ (16,877) Fixed assets, net ​ ​ ​ $ 5,487 ​ $ 6,326 ​

Inventory

Inventory	3 Months Ended
	Mar. 31, 2021
Inventory [Abstract]
Inventory	7. Inventory Inventories are stated at the lower of cost or market. Inventories consisted of the following: ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ March 31, 2021 December 31, 2020 ​ ​ (in thousands) Work-in-process ​ $ 8,463 ​ $ 8,394 Finished goods ​ 529 ​ 633 Inventory ​ $ 8,992 ​ $ 9,027 ​

Leases

Leases	3 Months Ended
	Mar. 31, 2021
Leases [Abstract]
Leases	8. Leases The Company leases various office spaces under non-cancelable operating leases with original lease periods expiring between the first quarter of 2022 and 2025. 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 right-of-use (“ROU”) assets and lease liabilities as they are not reasonably certain of exercise. Operating lease assets and liabilities are classified on the condensed consolidated balance sheets as follows: ​ ​ ​ ​ ​ ​ ​ ​ ​ Leases ​ Classification ​ March 31, 2021 ​ December 31, 2020 Assets ​ ​ ​ (in thousands) Operating lease assets ​ Other assets ​ $ 11,161 ​ $ 12,327 Total leased assets ​ ​ ​ $ 11,161 ​ $ 12,327 ​ ​ ​ ​ ​ ​ ​ ​ ​ Liabilities ​ ​ ​ ​ ​ ​ ​ ​ Current ​ ​ ​ ​ ​ ​ ​ ​ Operating lease liabilities ​ Accounts payable, accrued expenses and other liabilities ​ $ 7,348 ​ $ 7,248 Noncurrent ​ ​ ​ ​ ​ ​ ​ ​ Operating lease liabilities ​ Long-term other liabilities ​ ​ 5,762 ​ ​ 7,684 Total operating lease liabilities ​ ​ ​ $ 13,110 ​ $ 14,932 ​ Operating lease costs for the three-month periods ended March 31, 2021 and 2020, are as follows: ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Three Months Ended March 31, Lease Cost ​ Classification ​ 2021 ​ 2020 ​ ​ ​ ​ (in thousands) Operating lease cost ​ Selling, general and administrative expenses ​ $ 1,685 ​ $ 1,739 Short-term lease cost ​ Selling, general and administrative expenses ​ ​ 639 ​ ​ 421 Variable lease cost ​ Selling, general and administrative expenses ​ ​ 381 ​ ​ 247 Sublease income ​ Other income, net ​ ​ — ​ ​ (120) Net lease cost ​ ​ ​ $ 2,705 ​ $ 2,287 ​ The weighted-average remaining term of the Company’s operating leases was 2.7 years and the weighted-average discount rate used to measure the present value of the Company’s operating lease liabilities was 5.1% as of March 31, 2021. Cash payments included in the measurement of the Company’s operating lease liabilities reported in operating cash flows were $2.2 million and $1.8 million for the three months ended March 31, 2021 and 2020, respectively. During the three months ended March 31, 2020, the Company obtained a ROU asset of $1.0 million in exchange for new operating lease obligations of $1.0 million. Maturities of the Company’s operating lease liabilities, which do not include short-term leases, as of March 31, 2021 are as follows: ​ ​ ​ ​ Maturity of Lease Liabilities ​ Operating leases ​ ​ (in thousands) 2021 (remaining) ​ $ 5,877 2022 ​ ​ 3,613 2023 ​ ​ 2,149 2024 ​ ​ 1,616 2025 ​ ​ 1,032 Thereafter ​ ​ — Total lease payments ​ ​ 14,287 Less: Present value discount ​ ​ (1,177) Total operating lease liabilities ​ $ 13,110 ​

Accounts Payable, Accrued Expen

Accounts Payable, Accrued Expenses and Other Liabilities	3 Months Ended
	Mar. 31, 2021
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, 2021 December 31, 2020 ​ ​ (in thousands) Accounts payable ​ $ 12,583 ​ $ 24,594 Accrued employee compensation ​ 15,629 ​ 27,154 Accrued contracted services ​ 53,776 ​ 62,425 Accrued restructuring ​ ​ 652 ​ ​ 2,504 Accrued rebates, discounts and other incentives ​ ​ 41,905 ​ ​ 38,172 Operating lease liabilities ​ ​ 7,348 ​ ​ 7,248 Other liabilities ​ ​ 8,890 ​ ​ 8,942 Accounts payable, accrued expenses and other liabilities ​ $ 140,783 ​ $ 171,039 ​ The Company has $28.9 million and $27.4 million in rebates as of March 31, 2021 and December 31, 2020, respectively, included in Accrued rebates, discounts and other incentives, for a European jurisdiction in which final pricing is subject to ongoing negotiations with the government. ​ Research & Development Tax Credit ​ The Company has benefited from the U.K. Small and Medium-sized Enterprise R&D Tax Credit scheme, or the SME scheme, under which it can obtain a tax credit of up to 33.4% of eligible research and development expenses incurred by the Company in the U.K. Eligible expenses generally include employment costs for research staff, consumables, software and certain internal overhead costs incurred as part of research projects. ​ The Company has submitted claims seeking to obtain tax credits for qualifying R&D expenses incurred in the 2015, 2016, and 2017 calendar years. ​ With respect to the 2017 claim, in June 2020, the Company received a payment of $9.4 million from Her Majesty’s Revenue and Customs (“HMRC”), the U.K.’s government tax authority. Given the claim review has not been finalized for the 2017 year, the $9.4 million credit received along with an additional $1.1 million due to foreign currency translation are recorded as a deferred liability within Accounts payable, accrued expenses, and other liabilities. ​

Long-Term Debt

Long-Term Debt	3 Months Ended
	Mar. 31, 2021
Long-Term Debt [Abstract]
Long-Term Debt	10. Long-Term Debt Debt, net of discounts and deferred financing costs, consisted of the following: ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ March 31, 2021 December 31, 2020 ​ ​ (in thousands) 2023 Convertible Notes ​ $ 460,000 ​ $ 460,000 2026 Convertible Notes ​ ​ 230,000 ​ ​ 230,000 Long-term debt, gross ​ ​ 690,000 ​ ​ 690,000 Less: Unamortized debt discounts and fees ​ ​ (121,886) ​ ​ (129,418) Long-term debt, net ​ $ 568,114 ​ $ 560,582 ​ 2019 Offering ​ On May 14, 2019, the Company issued and sold $230.0 million aggregate principal amount of 2.00% Convertible Senior Notes due 2026 (the “2026 Convertible Notes”). The Company received net proceeds from the sale of the 2026 Convertible Notes of $223.4 million, after deducting underwriting discounts, commissions and estimated offering expenses of approximately $6.6 million. The 2026 Convertible Notes were issued pursuant to a Second Supplemental Indenture, dated as of May 14, 2019 (the “Second Supplemental Indenture”), which supplements the Indenture (the “Base Indenture”), as supplemented by a First Supplemental Indenture (the “First Supplemental Indenture” and collectively with the Base Indenture and the Second Supplemental Indenture, the “Indenture”), each dated as of July 6, 2016, by and between the Company and U.S. Bank National Association, as trustee. The 2026 Convertible Notes are senior unsecured obligations of the Company, bear interest at a fixed rate of 2.00% per annum (payable semi-annually on May 15 and November 15 of each year, beginning on November 15, 2019) and will mature on May 15, 2026, unless earlier repurchased, redeemed or converted. Holders may convert their 2026 Convertible Notes at their option at any time prior to the close of business on the business day immediately preceding February 15, 2026 only under the following circumstances: (i) during any calendar quarter (and only during such calendar quarter) commencing after the calendar quarter ended on June 30, 2019, if the last reported sale price of the Company’s common stock for at least 20 trading days (whether or not consecutive) during a period of 30 consecutive trading days ending on the last trading day of the immediately preceding calendar quarter is greater than 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 2026 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 2026 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 February 15, 2026 until the close of business on the business day immediately preceding the maturity date, holders may convert their 2026 Convertible Notes at any time, regardless of the foregoing circumstances. Upon conversion of the 2026 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 2026 Convertible Notes is 9.2123 shares of the Company’s common stock per $1,000 principal amount of 2026 Convertible Notes, which is equivalent to an initial conversion price of approximately $108.55 per share of the Company’s common stock. The conversion rate is subject to adjustment in some events but will not be adjusted for any accrued and unpaid interest. In addition, following certain corporate events that occur prior to the maturity date, the Company will increase the conversion rate for a holder who elects to convert its 2026 Convertible Notes in connection with such a corporate event in certain circumstances. The Company may not redeem the 2026 Convertible Notes prior to May 20, 2023. The Company may redeem for cash all or any portion of the 2026 Convertible Notes, at the Company’s option, on or after May 20, 2023, 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 2026 Convertible Notes to be redeemed, plus accrued and unpaid interest to, but excluding, the redemption date. No sinking fund is provided for the 2026 Convertible Notes. 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 2026 Convertible Notes at a fundamental change repurchase price equal to 100% of the principal amount of the 2026 Convertible Notes to be repurchased, plus accrued and unpaid interest to, but excluding, the fundamental change repurchase date. The Indenture provides for customary events of default. In accordance with Accounting Standards Codification (“ASC”) Subtopic 470-20, “Debt with Conversion and Other Options” (“ASC 470-20”), the Company used an effective interest rate of 9.9% to determine the liability component of the 2026 Convertible Notes. This resulted in the recognition of $137.5 million as the liability component of the 2026 Convertible Notes and the recognition of the residual $85.9 million as the debt discount with a corresponding increase to additional paid-in capital for the equity component of the 2026 Convertible Notes. The underwriting discount and estimated offering expenses totaling $6.6 million were allocated between the debt and equity issuance costs in proportion to the allocation of the liability and equity components of the 2026 Convertible Notes. Accordingly, equity issuance costs of $2.5 million were recorded as an offset to additional paid-in capital and total debt issuance costs of $4.1 million were recorded on the issuance date and are reflected in the unaudited condensed consolidated balance sheet as a direct deduction from the carrying value of the associated debt liability. The debt discount and debt issuance costs will be amortized as non-cash interest expense through May 15, 2026. The fair value of the 2026 Convertible Notes was approximately $146.8 million and $142.8 million at March 31, 2021 and December 31, 2020, respectively, and was determined using Level 2 inputs based on quoted market values. 2016 Offerings On July 6, 2016, the Company issued and sold $460.0 million aggregate principal amount of 3.25% Convertible Senior Notes due 2023 (the “2023 Convertible Notes”, and together with the 2026 Convertible Notes, the “Convertible Notes”). The Company received net proceeds from the sale of the 2023 Convertible Notes of $447.6 million, after deducting underwriting discounts, commissions 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 2023 Convertible Notes. The 2023 Convertible Notes were issued pursuant to the Base Indenture, as supplemented by the First Supplemental Indenture. The 2023 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 2023 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 the calendar quarter ended on 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 2023 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 2023 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 2023 Convertible Notes at any time, regardless of the foregoing circumstances. Upon conversion of the 2023 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 2023 Convertible Notes is 5.0358 shares of the Company’s common stock per $1,000 principal amount of 2023 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 2023 Convertible Notes at a fundamental change repurchase price equal to 100% of the principal amount of the 2023 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 2023 Convertible Notes converted in connection with such make-whole fundamental change. The Company may not redeem the 2023 Convertible Notes prior to July 6, 2021. The Company may redeem for cash all or part of the 2023 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 2023 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 2023 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 2023 Convertible Notes, as the case may be, upon conversion of the 2023 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 2023 Convertible Notes and is subject to anti-dilution adjustments substantially similar to those applicable to the conversion rate of the 2023 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. The Capped Call Transactions are considered to be instruments indexed to the Company’s own shares and met the criteria to be classified within equity and are therefore not remeasured. ​ In accordance with ASC 470-20, the Company used an effective interest rate of 8.4% to determine the liability component of the 2023 Convertible Notes. This resulted in the recognition of $334.4 million as the liability component of the 2023 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 2023 Convertible Notes. ​ The fair value of the 2023 Convertible Notes was approximately $380.7 million and $363.7 million at March 31, 2021 and December 31, 2020, respectively, and was determined using Level 2 inputs based on quoted market values. ​ Interest Expense on Convertible Notes The table summarizes the total interest expense recognized in the periods presented: ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Three Months Ended March 31, ​ 2021 2020 ​ ​ (in thousands) Contractual interest expense ​ $ 4,887 ​ $ 4,887 Amortization of debt discount ​ ​ 6,861 ​ ​ 6,276 Amortization of debt issuance costs ​ 671 ​ 614 Total interest expense ​ $ 12,419 ​ $ 11,777 ​ Accrued interest on the Convertible Notes was approximately $5.5 million and $8.1 million as of March 31, 2021 and December 31, 2020, respectively. The Company recorded debt issuance costs of $19.0 million, which are being amortized using the effective interest method. As of March 31, 2021, and December 31, 2020, $10.0 million and $10.7 million, respectively, of debt issuance costs are recorded on the condensed consolidated balance sheets in Long-term debt. Cash payments for interest were $7.5 million and $7.5 million for the three months ended March 31, 2021 and 2020, respectively.

Product Revenue, Net

Product Revenue, Net	3 Months Ended
	Mar. 31, 2021
Product Revenue, Net [Abstract]
Product Revenue, Net	11. Product Revenue, Net The Company recognized net sales of Ocaliva of $81.7 million and $72.7 million for the three months ended March 31, 2021 and 2020, respectively. The table below summarizes consolidated product revenue, net by region: ​ ​ ​ ​ ​ ​ ​ ​ ​ Three Months Ended March 31, ​ 2021 2020 ​ ​ (in thousands) Product revenue, net: ​ ​ U.S. ​ $ 57,299 ​ $ 50,779 ex-U.S. ​ 24,362 ​ 21,873 Total product revenue, net ​ $ 81,661 ​ $ 72,652 ​ ​ ​ ​ ​ ​ Credit Losses ​ The following table summarizes the allowance for credit losses activity on the Company’s trade receivables for the three-month period ended March 31, 2021 (in thousands): ​ ​ ​ ​ Balance at December 31, 2020 $ 235 Provision for credit losses ​ 0 Write-offs ​ (37) Balance at March 31, 2021 $ 198 ​

Restructuring Expenses

Restructuring Expenses	3 Months Ended
	Mar. 31, 2021
Restructuring Expenses
Restructuring Expenses	12. Restructuring Expenses ​ The following table reflects total expenses related to restructuring activities recognized within the Condensed Consolidated Statements of Operations as restructuring costs: ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Three Months Ended March 31, ​ 2021 2020 ​ (in thousands) Employee compensation costs $ 157 $ — Equity compensation costs 4 ​ — Total restructuring costs $ 161 ​ $ — ​ As of March 31, 2021, the cumulative restructuring costs incurred under the 2020 Workforce Plan were $14.8 million. In the three months ended March 31, 2021, the Company recorded an immaterial amount in non-cash stock-based compensation expense in association with the acceleration of the vesting of certain options and restricted stock units (“RSUs”) held by terminated employees. ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Severance and Related Costs ​ ​ (in thousands) Accrued balance at December 31, 2020 ​ $ 2,504 Charges incurred ​ ​ 180 Cash payments made ​ ​ (1,681) Other reserve adjustments ​ ​ (351) Accrued balance at March 31, 2021 ​ $ 652 ​

Stock Compensation

Stock Compensation	3 Months Ended
	Mar. 31, 2021
Stock Compensation [Abstract]
Stock Compensation	13. 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, 2021, the number of shares available for issuance under the 2012 Plan increased by 1,211,533 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, 2021 was determined utilizing a Black-Scholes option-pricing model at the date of grant. The fair value of the RSUs granted in the three months ended March 31, 2021 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, 2021 was determined utilizing the Monte Carlo simulation method. 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. There are no awards with performance conditions outstanding as of March 31, 2021. ​ The following table summarizes stock option activity during the three months ended March 31, 2021: ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Weighted ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Average ​ ​ ​ ​ ​ Number ​ Weighted ​ Remaining ​ Aggregate ​ ​ of Options ​ Average ​ Contractual ​ Intrinsic Value ​ (in thousands) Exercise Price Term (years) (in thousands) Outstanding at December 31, 2020 2,199 ​ $ 96.92 6.9 ​ $ 146 Granted 836 ​ $ 29.99 — ​ $ — Exercised — ​ $ — — ​ $ — Cancelled/forfeited (159) ​ $ 70.18 — ​ $ — Expired (118) ​ $ 94.33 — ​ $ — Outstanding at March 31, 2021 2,758 ​ $ 78.30 7.5 ​ $ 118 Expected to vest 1,341 ​ $ 53.33 9.1 ​ $ 32 Exercisable 1,417 ​ $ 101.93 6.0 ​ $ 86 ​ The aggregate intrinsic value of options is calculated as the difference between the exercise price of the underlying options and the fair value of the Company’s common stock for those options that had exercise prices lower than the fair value of the Company’s common stock. As of March 31, 2021, the total compensation cost related to non-vested option awards not yet recognized is approximately $37.9 million with a weighted average remaining vesting period of 1.63 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, ​ 2021 2020 ​ Volatility 65.2 - 65.9 % 61.9 - 87.1 % Expected term (in years) 6.0 6.0 Risk-free rate 0.4 - 0.7 % 0.9 - 1.7 % Expected dividend yield — % — % ​ 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, 2021: ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Weighted ​ ​ Number of ​ Average Grant Date ​ Awards Fair Value ​ ​ (in thousands) ​ ​ ​ Non-vested awards at December 31, 2020 799 ​ $ 72.43 Granted 691 ​ $ 31.66 Vested ​ (70) ​ $ 64.75 Forfeited (182) ​ $ 69.06 Non-vested awards at March 31, 2021 1,238 ​ $ 50.64 ​ As of March 31, 2021, there is approximately $48.6 million of total unrecognized compensation expense related to unvested RSUs, RSAs, PRSUs and PRSAs, which is expected to be recognized over a weighted average vesting period of 1.76 years. During the three months ended March 31, 2021, the Company granted a total of 163,600 PRSUs to certain of the Company’s executive officers (of which 23,900 were subsequently forfeited upon employee termination). 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 Company recorded approximately $0.4 million of stock-based compensation related to such PRSUs granted during the three months ended March 31, 2021. Stock-based compensation expense has been reported in the Company’s condensed consolidated statements of operations as follows: ​ ​ ​ ​ ​ ​ ​ ​ ​ Three Months Ended March 31, ​ 2021 2020 ​ ​ (in thousands) Selling, general and administrative ​ $ 6,389 ​ $ 9,723 Research and development ​ 2,026 ​ 2,750 Restructuring ​ ​ 4 ​ ​ — Total stock-based compensation ​ $ 8,419 ​ $ 12,473 ​

Net Loss Per Share

Net Loss Per Share	3 Months Ended
	Mar. 31, 2021
Net loss per common and potential common share:
Net Loss Per Share	14. 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-month periods ended March 31, 2021 and 2020, 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 for the three-month periods ended March 31, 2021 and 2020, as the inclusion thereof would have been anti-dilutive: ​ ​ ​ ​ ​ ​ ​ Three Months Ended March 31, ​ 2021 2020 ​ ​ (in thousands) Shares issuable upon conversion of Convertible Notes ​ 4,435 ​ 4,435 Options 2,730 2,446 Unvested restricted stock units 1,195 871 Total 8,360 7,752 ​

Commitments and Contingencies

Commitments and Contingencies	3 Months Ended
	Mar. 31, 2021
Commitments and Contingencies [Abstract]
Commitments and Contingencies	15. Commitments and Contingencies Legal Proceedings The Company is involved in various disputes, legal proceedings and litigation in the course of its business, including the matters described below and, from time to time, governmental inquiries and investigations and 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. Shareholder Litigation Separately, 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 above. In addition, 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 above. On November 5, 2020, a purported shareholder class action, initially styled Chauhan v. Intercept Pharmaceuticals, Inc., et al., was filed in the United States District Court for the Eastern District of New York, naming the Company and certain of its officers as defendants. The lawsuit was transferred to the United States District Court for the Southern District of New York on January 4, 2021. The Court appointed lead plaintiff in the lawsuit on January 25, 2021, and the lead plaintiff filed a corrected amended complaint on March 15, 2021, captioned Richard Rice, as Trustee of the Richard E. and Melinda Rice Revocable Family Trust 5/9/90, and Christian Stankevitz v. Intercept Pharmaceuticals, Inc., et al., naming the Company and certain of its current and former officers as defendants. The lead plaintiff claims to be suing on behalf of anyone who purchased or otherwise acquired the Company’s securities between September 28, 2019 and October 7, 2020. This lawsuit alleges that material misrepresentations and/or omissions of material fact were made in the Company’s public disclosures during the period from September 28, 2019 to October 7, 2020, in violation of Sections 10(b) and 20(a) of the Exchange Act, and Rule 10b-5 promulgated thereunder. The alleged improper disclosures relate to statements regarding the Company’s New Drug Application for OCA for the treatment of liver fibrosis due to NASH and the use of Ocaliva in patients with PBC, as well as the Company’s operations, financial performance and prospects. The plaintiff seeks unspecified monetary damages on behalf of the putative class, and an award of costs and expenses, including attorney’s fees. On April 26, 2021, the Company filed a motion to dismiss the amended complaint. Separately, on December 29, 2020, a follow-on derivative suit, styled Rabinovich v. Fundarò, et al., was filed in the United States District Court for the Southern District of New York by shareholder Delfin Rabinovich based on substantially the same allegations as those set forth in the securities case immediately above. This lawsuit was subsequently transferred to the United States District Court for the District of Delaware on January 28, 2021. On February 1, 2021, a second follow-on derivative suit, styled Fung v. Fundarò, et al., was filed in the United States District Court for the District of Delaware based on the substantially same allegations as those set forth in the securities case immediately above and the Rabinovich derivative action. On March 1, 2021, these follow-on derivative suits were consolidated in a single suit titled In re Intercept Pharmaceuticals, Inc. Derivative Litigation. On March 15, 2021, the District of Delaware entered an order staying the consolidated derivative litigation pending a decision on the motion to dismiss in the related 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. Patent Litigation The Company has received paragraph IV certification notice letters from six generic drug manufacturers indicating that each such manufacturer has submitted to the FDA an Abbreviated New Drug Application (“ANDA”) seeking approval to manufacture and sell a generic version of the Company’s 5 mg and 10 mg dosage strengths of Ocaliva® (obeticholic acid) for PBC prior to the expiration of certain patents protecting Ocaliva. Apotex Abbreviated New Drug Application In July 2020, the Company received a paragraph IV certification notice (the “Apotex PIV Notice”) from Apotex Inc. (“Apotex”) indicating that Apotex has submitted to the FDA an ANDA seeking approval to manufacture and sell a generic version of the Company’s 5 mg and 10 mg dosage strengths of Ocaliva® (obeticholic acid) for PBC prior to the expiration of the Company’s U.S. Patents Nos. 9,238,673 (the “‘673 Patent”), 10,047,117 (the “‘117 Patent”), 10,052,337 (the “‘337 Patent”), and 10,174,073 (the “‘073 Patent”, and collectively with the ‘673 Patent, ‘117 Patent and ‘337 Patent, the “Apotex Challenged Patents”), which are listed for Ocaliva in the FDA’s Approved Drug Products with Therapeutic Equivalence Evaluations (referred to as the “Orange Book”). The Apotex PIV Notice alleges that the Apotex Challenged Patents are invalid, unenforceable, and/or will not be infringed by the commercial manufacture, use or sale of the generic products described in Apotex’s ANDA. Apotex did not make a paragraph IV certification against the Company’s U.S. Patents Nos. 7,138,390 (the “‘390 Patent”), 8,058,267 (the “‘267 Patent”) or 8,377,916 the (“‘916 Patent”), which are also listed for Ocaliva in the Orange Book. The Company initiated a patent infringement suit against Apotex in the United States District Court for the District of Delaware within 45 days of receipt of the Apotex PIV Notice. As a result, under the Drug Price Competition and Patent Term Restoration Act of 1984 (the “Hatch-Waxman Act”), the FDA cannot grant final approval of Apotex’s ANDA before November 27, 2023 or a court decision in Apotex’s favor, whichever is earlier. Recently, the U.S. Patent and Trademark Office (the “USPTO”) awarded the Company two additional patents that were subsequently listed in the Orange Book for Ocaliva: U.S. Patents Nos. 10,751,349 (the “‘349 Patent”) and 10,758,549 (the “‘549 Patent”). In September and October 2020, the Company received additional paragraph IV certification notices from Apotex challenging the ‘349 Patent and the ‘549 Patent, respectively. The Company amended its complaint against Apotex in November 2020 to add infringement allegations for the ‘549 Patent. In January 2021, the Company received a further paragraph IV certification notice from Apotex challenging a reissue patent, U.S. Patent No. RE 48,286 (the “‘286 Patent”), as described below. The Company further amended its complaint against Apotex in March 2021 to add infringement allegations for the ‘286 Patent. In response to the Company’s allegations of infringement, Apotex has taken the position that the patents asserted against it are invalid and/or not infringed. Lupin Abbreviated New Drug Application In July 2020, the Company received a paragraph IV certification notice (the “Lupin PIV Notice”) from Lupin Limited (“Lupin”) indicating that Lupin has submitted to the FDA an ANDA seeking approval to manufacture and sell a generic version of the Company’s 5 mg and 10 mg dosage strengths of Ocaliva® (obeticholic acid) for PBC prior to the expiration of the ‘390 Patent, the ‘673 Patent, the ‘117 Patent, the ‘337 Patent and the ‘073 Patent (collectively, the “Lupin Challenged Patents”), which are listed for Ocaliva in the FDA’s Orange Book. The Lupin PIV Notice alleges that the Lupin Challenged Patents are invalid, unenforceable, and/or will not be infringed by the commercial manufacture, use or sale of the generic products described in Lupin’s ANDA. Lupin did not make a paragraph IV certification against the ‘267 Patent or the ‘916 Patent, which are also listed for Ocaliva in the Orange Book. The Company initiated a patent infringement suit against Lupin in the United States District Court for the District of Delaware within 45 days of receipt of the Lupin PIV Notice. As a result, under the Hatch-Waxman Act, the FDA cannot grant final approval of Lupin’s ANDA before November 27, 2023 or a court decision in Lupin’s favor, whichever is earlier. In September 2020, the Company received an additional paragraph IV certification notice from Lupin challenging the ‘349 Patent and the ‘549 Patent. In November 2020, the Company received an additional amended paragraph IV certification notice from Lupin challenging the ‘286 Patent. The Company amended its complaint against Lupin in November 2020 to add infringement allegations for the ‘549 Patent and to substitute the ‘286 Patent for the ‘390 Patent. In response to the Company’s allegations of infringement, Lupin has taken the position that the patents asserted against it are invalid and/or not infringed. Amneal Abbreviated New Drug Application In July 2020, the Company received a paragraph IV certification notice (the “Amneal PIV Notice”) from Amneal Pharmaceuticals of New York, LLC, as U.S. agent for Amneal EU Limited (“Amneal”), indicating that Amneal has submitted to the FDA an ANDA seeking approval to manufacture and sell a generic version of the Company’s 5 mg and 10 mg dosage strengths of Ocaliva® (obeticholic acid) for PBC prior to the expiration of the ‘673 Patent, the ‘117 Patent, the ‘337 Patent and the ‘073 Patent (collectively, the “Amneal Challenged Patents”), which are listed for Ocaliva in the FDA’s Orange Book. The Amneal PIV Notice alleges that the Amneal Challenged Patents are invalid, unenforceable, and/or will not be infringed by the commercial manufacture, use or sale of the generic products described in Amneal’s ANDA. Amneal did not make a paragraph IV certification against the ‘390 Patent, the ‘267 Patent or the ‘916 Patent, which are also listed for Ocaliva in the Orange Book. The Company initiated a patent infringement suit against Amneal in the United States District Court for the District of Delaware within 45 days of receipt of the Amneal PIV Notice. As a result, under the Hatch-Waxman Act, the FDA cannot grant final approval of Amneal’s ANDA before November 27, 2023 or a court decision in Amneal’s favor, whichever is earlier. In October 2020, the Company received an additional paragraph IV certification notice from Amneal challenging the ‘349 Patent and the ‘549 Patent. The Company amended its complaint against Amneal in November 2020 to add infringement allegations for the ‘349 Patent and the ‘549 Patent. In response to the Company’s allegations of infringement, Amneal has taken the position that the patents asserted against it are invalid and/or not infringed. Optimus Abbreviated New Drug Application In July 2020, the Company received a paragraph IV certification notice (the “Optimus PIV Notice”) from Optimus Pharma Pvt Ltd (“Optimus”) indicating that Optimus has submitted to the FDA an ANDA seeking approval to manufacture and sell a generic version of the Company’s 5 mg and 10 mg dosage strengths of Ocaliva® (obeticholic acid) for PBC prior to the expiration of the ‘390 Patent, the ‘673 Patent, the ‘117 Patent, the ‘337 Patent and the ‘073 Patent (collectively, the “Optimus Challenged Patents”) which are listed for Ocaliva in the FDA’s Orange Book. The Optimus PIV Notice alleges that the Optimus Challenged Patents are invalid, unenforceable, and/or will not be infringed by the commercial manufacture, use or sale of the generic products described in Optimus’s ANDA. Optimus did not make a paragraph IV certification against the ‘267 Patent or the ‘916 Patent, which are also listed for Ocaliva in the Orange Book. The Company initiated a patent infringement suit against Optimus in the United States District Court for the District of Delaware within 45 days of receipt of the Optimus PIV Notice. As a result, under the Hatch-Waxman Act, the FDA cannot grant final approval of Optimus’s ANDA before November 27, 2023 or a court decision in Optimus’s favor, whichever is earlier. In October 2020, the Company received an additional paragraph IV certification notice from Optimus challenging the ‘349 Patent and the ‘549 Patent. The Company amended its complaint against Optimus in November 2020 to add infringement allegations for the ‘549 Patent and to substitute the ‘286 Patent for the ‘390 Patent. In response to the Company’s allegations of infringement, Optimus has taken the position that the patents asserted against it are invalid and/or not infringed. MSN Abbreviated New Drug Application In July 2020, the Company received a paragraph IV certification notice (the “MSN PIV Notice”) from MSN Pharmaceuticals Inc. and MSN Laboratories Private Limited (collectively, “MSN”) indicating that MSN has submitted to the FDA an ANDA seeking approval to manufacture and sell a generic version of the Company’s 5 mg and 10 mg dosage strengths of Ocaliva® (obeticholic acid) for PBC prior to the expiration of the ‘390 Patent, the ‘673 Patent, the ‘117 Patent, the ‘337 Patent and the ‘073 Patent (collectively, the “MSN Challenged Patents”) which are listed for Ocaliva in the FDA’s Orange Book. The MSN PIV Notice alleges that the MSN Challenged Patents are invalid, unenforceable, and/or will not be infringed by the commercial manufacture, use or sale of the generic products described in MSN’s ANDA. MSN did not make a paragraph IV certification against the ‘267 Patent or the ‘916 Patent, which are also listed for Ocaliva in the Orange Book. The Company initiated a patent infringement suit against MSN in the United States District Court for the District of Delaware within 45 days of receipt of the MSN PIV Notice. As a result, under the Hatch-Waxman Act, the FDA cannot grant final approval of MSN’s ANDA before November 27, 2023 or a court decision in MSN’s favor, whichever is earlier. In November 2020, the Company received an additional paragraph IV certification notice from MSN challenging the ‘349 Patent, the ‘549 Patent, and the ‘286 Patent. The Company amended its complaint against MSN in December 2020 to add infringement allegations for the ‘549 Patent and to substitute the ‘286 Patent for the ‘390 Patent. In response to the Company’s allegations of infringement, MSN has taken the position that the patents asserted against it are invalid and/or not infringed. DRL Abbreviated New Drug Application In December 2020, the Company received a paragraph IV certification notice (the “DRL PIV Notice”) from Dr. Reddy’s Laboratories, Inc. and Dr. Reddy’s Laboratories, Ltd. (collectively, “DRL”) indicating that DRL has submitted to the FDA an ANDA seeking approval to manufacture and sell a generic version of the Company’s 5 mg and 10 mg dosage strengths of Ocaliva® (obeticholic acid) for PBC prior to the expiration of the ‘286 Patent, the ‘390 Patent, the ‘673 Patent, the ‘117 Patent, the ‘337 Patent, the ‘073 Patent, the ‘349 Patent and the ‘549 Patent (collectively, the “DRL Challenged Patents”) which are listed for Ocaliva in the FDA’s Orange Book. The DRL PIV Notice alleges that the DRL Challenged Patents are invalid, unenforceable, and/or will not be infringed by the commercial manufacture, use or sale of the generic products described in DRL’s ANDA. DRL did not make a paragraph IV certification against the ‘267 Patent or the ‘916 Patent, which are also listed for Ocaliva in the Orange Book. The Company initiated a patent infringement suit against DRL in the United States District Court for the District of Delaware within 45 days of receipt of the DRL PIV Notice. As a result, under the Hatch-Waxman Act, the FDA cannot grant final approval of DRL’s ANDA before November 27, 2023 or a court decision in DRL’s favor, whichever is earlier. In response to the Company’s allegations of infringement, DRL has taken the position that the patents asserted against it are invalid and/or not infringed. In October 2020, the USPTO granted to the Company a reissue patent, ‘286 Patent. By operation of law, the ‘390 Patent was withdrawn and replaced by the ‘286 Patent, which contains composition of matter claims to OCA and has the same term as the ‘390 Patent. In February 2021, a patent term extension certificate was issued, which extends the term of the ‘286 Patent into 2027. The ‘286 Patent has been listed in the Orange Book. These proceedings are costly and time consuming. Successful challenges to the Company’s patent or other intellectual property rights through these proceedings could result in a loss of rights in the relevant jurisdiction and may allow third parties to use the Company’s proprietary technologies without a license from the Company or its collaborators. While the Company intends to vigorously defend and enforce its intellectual property rights protecting Ocaliva, the Company can offer no assurance as to when the lawsuits will be decided, whether the lawsuits will be successful, or that a generic equivalent of Ocaliva will not be approved and enter the market before the expiration of the Company’s patents.

Basis of Presentation (Policy)

Basis of Presentation (Policy)	3 Months Ended
	Mar. 31, 2021
Basis of Presentation [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. ​ We are not presently aware of any events or circumstances arising from the coronavirus (“COVID-19”) pandemic that would require us to update our estimates or judgments or revise the carrying value of our assets or liabilities.

Summary of Significant Accoun_2

Summary of Significant Accounting Policies (Policies)	3 Months Ended
	Mar. 31, 2021
Summary of Significant Accounting Policiies
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 money market funds are classified within Level 1 of the fair value hierarchy because they are valued using quoted prices in active markets. Investment debt securities 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, 2021
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, 2021 and December 31, 2020: ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ As of March 31, 2021 ​ ​ ​ ​ ​ Allowance ​ Gross ​ Gross ​ ​ ​ ​ ​ ​ ​ ​ for Credit ​ Unrealized ​ Unrealized ​ ​ ​ ​ Amortized Cost ​ Losses Gains Losses Fair Value ​ ​ (in thousands) Cash and cash equivalents: ​ ​ ​ ​ ​ ​ ​ Cash and money market funds ​ $ 85,946 ​ $ — ​ $ — ​ $ — ​ $ 85,946 Commercial paper ​ ​ 2,000 ​ ​ — ​ ​ — ​ ​ — ​ ​ 2,000 U.S. treasuries ​ ​ 5,000 ​ ​ — ​ ​ — ​ ​ — ​ ​ 5,000 Total cash and cash equivalents ​ ​ 92,946 ​ ​ — ​ ​ — ​ ​ — ​ ​ 92,946 Investment debt securities: ​ ​ ​ ​ ​ Commercial paper ​ 57,676 ​ — ​ 5 ​ (6) ​ 57,675 Corporate debt securities ​ 260,444 ​ — ​ 195 ​ (77) ​ 260,562 Total investment debt securities ​ 318,120 ​ — ​ 200 ​ (83) ​ 318,237 Total cash, cash equivalents and investment debt securities ​ $ 411,066 ​ $ — ​ $ 200 ​ $ (83) ​ $ 411,183 ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ As of December 31, 2020 ​ ​ ​ ​ ​ Allowance ​ Gross ​ Gross ​ ​ ​ ​ ​ ​ ​ ​ for Credit ​ Unrealized ​ Unrealized ​ ​ ​ ​ Amortized Cost ​ Losses Gains Losses ​ Fair Value ​ ​ (in thousands) ​ ​ ​ Cash and cash equivalents: ​ ​ ​ ​ ​ ​ ​ ​ Cash and money market funds ​ $ 58,151 ​ $ — ​ $ — ​ $ — ​ $ 58,151 Total cash and cash equivalents ​ ​ 58,151 ​ ​ — ​ ​ — ​ ​ — ​ ​ 58,151 Investment debt securities: ​ ​ ​ ​ ​ Commercial paper ​ 55,460 ​ — ​ 6 ​ (9) ​ 55,457 Corporate debt securities ​ 355,597 ​ — ​ 529 ​ (67) ​ 356,059 Total investment debt securities ​ 411,057 ​ — ​ 535 ​ (76) ​ 411,516 Total cash, cash equivalents and investment debt securities ​ $ 469,208 ​ $ — ​ $ 535 ​ $ (76) ​ $ 469,667
Available-for-sale Securities, Continuous Unrealized Loss Position, Fair Value	​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ As of March 31, 2021 ​ ​ Less than 12 months ​ 12 months or longer ​ Total ​ ​ (in thousands) ​ ​ ​ ​ ​ Gross ​ ​ ​ ​ Gross ​ ​ ​ ​ Gross ​ ​ ​ ​ ​ Unrealized ​ ​ ​ Unrealized ​ ​ ​ ​ Unrealized ​ Fair Value Losses Fair Value Losses Fair Value Losses Commercial paper ​ $ 23,184 ​ $ (6) ​ $ — ​ $ — ​ $ 23,184 ​ $ (6) Corporate debt securities ​ ​ 131,758 ​ ​ (77) ​ ​ — ​ ​ — ​ ​ 131,758 ​ ​ (77) Total ​ $ 154,942 ​ $ (83) ​ $ — ​ $ — ​ $ 154,942 ​ $ (83) ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ As of December 31, 2020 ​ ​ Less than 12 months ​ 12 months or longer ​ Total ​ ​ (in thousands) ​ ​ ​ ​ Gross ​ ​ Gross ​ ​ Gross ​ ​ ​ ​ ​ Unrealized ​ ​ ​ ​ Unrealized ​ ​ ​ ​ Unrealized ​ Fair Value Losses Fair Value Losses Fair Value Losses Commercial paper ​ $ 32,970 ​ $ (9) ​ $ — ​ $ — ​ $ 32,970 ​ $ (9) Corporate debt securities ​ 143,076 ​ (67) ​ — ​ — ​ 143,076 ​ (67) Total ​ $ 176,046 ​ $ (76) ​ $ — ​ $ — ​ $ 176,046 ​ $ (76)

Fair Value Measurements (Tables

Fair Value Measurements (Tables)	3 Months Ended
	Mar. 31, 2021
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, 2021 ​ ​ ​ ​ Assets ​ ​ ​ ​ Cash and cash equivalents: ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Money market funds ​ $ 64,204 ​ $ 64,204 ​ $ — ​ $ — Commercial paper ​ ​ 2,000 ​ ​ — ​ ​ 2,000 ​ ​ — U.S. treasuries ​ ​ 5,000 ​ ​ 5,000 ​ ​ — ​ ​ — Available-for-sale investment debt securities: ​ ​ ​ ​ ​ Commercial paper ​ 57,675 ​ — ​ 57,675 ​ — Corporate debt securities ​ 260,562 ​ — ​ 260,562 ​ — Total financial assets ​ $ 389,441 ​ $ 69,204 ​ $ 320,237 ​ $ — ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ December 31, 2020 ​ ​ ​ ​ Assets ​ ​ ​ ​ Cash and cash equivalents: ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Money market funds ​ $ 15,492 ​ $ 15,492 ​ $ — ​ $ — Available-for-sale investment debt securities: ​ ​ ​ ​ Commercial paper ​ 55,457 ​ — ​ 55,457 ​ — Corporate debt securities ​ 356,059 ​ — ​ 356,059 ​ — Total financial assets ​ $ 427,008 ​ $ 15,492 ​ $ 411,516 ​ $ —
Schedule of Available for Sale Securities Debt Maturities	See Note 10 for the carrying amount and estimated fair value of our and The aggregate fair value of all available-for-sale investment debt securities (commercial paper and corporate debt securities), by contractual maturity, are as follows: ​ ​ ​ ​ ​ ​ ​ ​ ​ Fair Value as of ​ March 31, 2021 December 31, 2020 ​ ​ (in thousands) Due in one year or less ​ $ 285,229 ​ $ 328,077 Due after one year through two years ​ 33,008 ​ 83,439 Total investment debt securities ​ $ 318,237 ​ $ 411,516 ​

Fixed Assets, Net (Tables)

Fixed Assets, Net (Tables)	3 Months Ended
	Mar. 31, 2021
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, 2021 December 31, 2020 ​ ​ ​ ​ (in thousands) Office equipment and software 3 ​ $ 5,369 ​ $ 5,364 Leasehold improvements Shorter of remaining lease term or useful life ​ 13,269 ​ 13,237 Furniture and fixtures 7 ​ 4,608 ​ 4,602 Subtotal ​ ​ ​ 23,246 ​ 23,203 Less: accumulated depreciation ​ ​ ​ (17,759) ​ (16,877) Fixed assets, net ​ ​ ​ $ 5,487 ​ $ 6,326

Inventory (Tables)

Inventory (Tables)	3 Months Ended
	Mar. 31, 2021
Inventory [Abstract]
Schedule of Inventory	Inventories are stated at the lower of cost or market. Inventories consisted of the following: ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ March 31, 2021 December 31, 2020 ​ ​ (in thousands) Work-in-process ​ $ 8,463 ​ $ 8,394 Finished goods ​ 529 ​ 633 Inventory ​ $ 8,992 ​ $ 9,027

Leases (Tables)

Leases (Tables)	3 Months Ended
	Mar. 31, 2021
Leases [Abstract]
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, 2021 ​ December 31, 2020 Assets ​ ​ ​ (in thousands) Operating lease assets ​ Other assets ​ $ 11,161 ​ $ 12,327 Total leased assets ​ ​ ​ $ 11,161 ​ $ 12,327 ​ ​ ​ ​ ​ ​ ​ ​ ​ Liabilities ​ ​ ​ ​ ​ ​ ​ ​ Current ​ ​ ​ ​ ​ ​ ​ ​ Operating lease liabilities ​ Accounts payable, accrued expenses and other liabilities ​ $ 7,348 ​ $ 7,248 Noncurrent ​ ​ ​ ​ ​ ​ ​ ​ Operating lease liabilities ​ Long-term other liabilities ​ ​ 5,762 ​ ​ 7,684 Total operating lease liabilities ​ ​ ​ $ 13,110 ​ $ 14,932
Schedule of operating lease costs	​ Operating lease costs for the three-month periods ended March 31, 2021 and 2020, are as follows: ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Three Months Ended March 31, Lease Cost ​ Classification ​ 2021 ​ 2020 ​ ​ ​ ​ (in thousands) Operating lease cost ​ Selling, general and administrative expenses ​ $ 1,685 ​ $ 1,739 Short-term lease cost ​ Selling, general and administrative expenses ​ ​ 639 ​ ​ 421 Variable lease cost ​ Selling, general and administrative expenses ​ ​ 381 ​ ​ 247 Sublease income ​ Other income, net ​ ​ — ​ ​ (120) Net lease cost ​ ​ ​ $ 2,705 ​ $ 2,287
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, 2021 are as follows: ​ ​ ​ ​ Maturity of Lease Liabilities ​ Operating leases ​ ​ (in thousands) 2021 (remaining) ​ $ 5,877 2022 ​ ​ 3,613 2023 ​ ​ 2,149 2024 ​ ​ 1,616 2025 ​ ​ 1,032 Thereafter ​ ​ — Total lease payments ​ ​ 14,287 Less: Present value discount ​ ​ (1,177) Total operating lease liabilities ​ $ 13,110

Accounts Payable, Accrued Exp_2

Accounts Payable, Accrued Expenses and Other Liabilities (Tables)	3 Months Ended
	Mar. 31, 2021
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, 2021 December 31, 2020 ​ ​ (in thousands) Accounts payable ​ $ 12,583 ​ $ 24,594 Accrued employee compensation ​ 15,629 ​ 27,154 Accrued contracted services ​ 53,776 ​ 62,425 Accrued restructuring ​ ​ 652 ​ ​ 2,504 Accrued rebates, discounts and other incentives ​ ​ 41,905 ​ ​ 38,172 Operating lease liabilities ​ ​ 7,348 ​ ​ 7,248 Other liabilities ​ ​ 8,890 ​ ​ 8,942 Accounts payable, accrued expenses and other liabilities ​ $ 140,783 ​ $ 171,039

Long-Term Debt (Tables)

Long-Term Debt (Tables)	3 Months Ended
	Mar. 31, 2021
Long-Term Debt [Abstract]
Schedule of Long-term Debt Instruments	Debt, net of discounts and deferred financing costs, consisted of the following: ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ March 31, 2021 December 31, 2020 ​ ​ (in thousands) 2023 Convertible Notes ​ $ 460,000 ​ $ 460,000 2026 Convertible Notes ​ ​ 230,000 ​ ​ 230,000 Long-term debt, gross ​ ​ 690,000 ​ ​ 690,000 Less: Unamortized debt discounts and fees ​ ​ (121,886) ​ ​ (129,418) Long-term debt, net ​ $ 568,114 ​ $ 560,582 ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Three Months Ended March 31, ​ 2021 2020 ​ ​ (in thousands) Contractual interest expense ​ $ 4,887 ​ $ 4,887 Amortization of debt discount ​ ​ 6,861 ​ ​ 6,276 Amortization of debt issuance costs ​ 671 ​ 614 Total interest expense ​ $ 12,419 ​ $ 11,777

Product Revenue, Net (Tables)

Product Revenue, Net (Tables)	3 Months Ended
	Mar. 31, 2021
Product Revenue, Net [Abstract]
Product Revenues	The table below summarizes consolidated product revenue, net by region: ​ ​ ​ ​ ​ ​ ​ ​ ​ Three Months Ended March 31, ​ 2021 2020 ​ ​ (in thousands) Product revenue, net: ​ ​ U.S. ​ $ 57,299 ​ $ 50,779 ex-U.S. ​ 24,362 ​ 21,873 Total product revenue, net ​ $ 81,661 ​ $ 72,652
Schedule of allowance for credit losses	​ ​ ​ ​ Balance at December 31, 2020 $ 235 Provision for credit losses ​ 0 Write-offs ​ (37) Balance at March 31, 2021 $ 198

Restructuring Expenses (Tables)

Restructuring Expenses (Tables)	3 Months Ended
	Mar. 31, 2021
Restructuring Expenses
Restructuring expenses activities	The following table reflects total expenses related to restructuring activities recognized within the Condensed Consolidated Statements of Operations as restructuring costs: ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Three Months Ended March 31, ​ 2021 2020 ​ (in thousands) Employee compensation costs $ 157 $ — Equity compensation costs 4 ​ — Total restructuring costs $ 161 ​ $ — ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Severance and Related Costs ​ ​ (in thousands) Accrued balance at December 31, 2020 ​ $ 2,504 Charges incurred ​ ​ 180 Cash payments made ​ ​ (1,681) Other reserve adjustments ​ ​ (351) Accrued balance at March 31, 2021 ​ $ 652

Stock Compensation (Tables)

Stock Compensation (Tables)	3 Months Ended
	Mar. 31, 2021
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, 2021: ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Weighted ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Average ​ ​ ​ ​ ​ Number ​ Weighted ​ Remaining ​ Aggregate ​ ​ of Options ​ Average ​ Contractual ​ Intrinsic Value ​ (in thousands) Exercise Price Term (years) (in thousands) Outstanding at December 31, 2020 2,199 ​ $ 96.92 6.9 ​ $ 146 Granted 836 ​ $ 29.99 — ​ $ — Exercised — ​ $ — — ​ $ — Cancelled/forfeited (159) ​ $ 70.18 — ​ $ — Expired (118) ​ $ 94.33 — ​ $ — Outstanding at March 31, 2021 2,758 ​ $ 78.30 7.5 ​ $ 118 Expected to vest 1,341 ​ $ 53.33 9.1 ​ $ 32 Exercisable 1,417 ​ $ 101.93 6.0 ​ $ 86
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, ​ 2021 2020 ​ Volatility 65.2 - 65.9 % 61.9 - 87.1 % Expected term (in years) 6.0 6.0 Risk-free rate 0.4 - 0.7 % 0.9 - 1.7 % 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, 2021: ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Weighted ​ ​ Number of ​ Average Grant Date ​ Awards Fair Value ​ ​ (in thousands) ​ ​ ​ Non-vested awards at December 31, 2020 799 ​ $ 72.43 Granted 691 ​ $ 31.66 Vested ​ (70) ​ $ 64.75 Forfeited (182) ​ $ 69.06 Non-vested awards at March 31, 2021 1,238 ​ $ 50.64 ​
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, ​ 2021 2020 ​ ​ (in thousands) Selling, general and administrative ​ $ 6,389 ​ $ 9,723 Research and development ​ 2,026 ​ 2,750 Restructuring ​ ​ 4 ​ ​ — Total stock-based compensation ​ $ 8,419 ​ $ 12,473

Net Loss Per Share (Tables)

Net Loss Per Share (Tables)	3 Months Ended
	Mar. 31, 2021
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 for the three-month periods ended March 31, 2021 and 2020, as the inclusion thereof would have been anti-dilutive: ​ ​ ​ ​ ​ ​ ​ Three Months Ended March 31, ​ 2021 2020 ​ ​ (in thousands) Shares issuable upon conversion of Convertible Notes ​ 4,435 ​ 4,435 Options 2,730 2,446 Unvested restricted stock units 1,195 871 Total 8,360 7,752

Summary of Significant Accoun_3

Summary of Significant Accounting Policies (Narrative) (Details) - USD ($) $ in Thousands	Mar. 31, 2021	Dec. 31, 2020
Accrued rebates, discounts and other incentives	$ 41,905	$ 38,172
Europe [Member]
Accrued rebates, discounts and other incentives	$ 28,900	$ 27,400

Cash, Cash Equivalents and In_3

Cash, Cash Equivalents and Investment Debt Securities (Narrative) (Details) $ in Millions	Mar. 31, 2021USD ($)security	Dec. 31, 2020USD ($)
Cash, Cash Equivalents, and Investment Debt Securities [Abstract]
Number of positions that were in a continuous unrealized loss position for more than twelve months | security	61
Accrued investment income receivable | $	$ 1.3	$ 2.5

Cash, Cash Equivalents and In_4

Cash, Cash Equivalents and Investment Debt Securities (Cash, Cash Equivalents and Investment Debt Securities) (Details) - USD ($) $ in Thousands	Mar. 31, 2021	Dec. 31, 2020
Cash and cash equivalents:
Cash and Cash Equivalents, Amortized Cost	$ 92,946	$ 58,151
Cash and cash equivalents, Fair Value	92,946	58,151
Investment Debt Securities Abstract
Total investments, Amortized Cost	318,120	411,057
Total cash and cash equivalents and investment debt securities, Amortized Cost	411,066	469,208
Allowance for Credit Losses	0
Total investments, Gross Unrealized Gains	200	535
Total cash and cash equivalents and investment debt securities, Gross Unrealized Gains	200
Total investments, Gross Unrealized Losses	(83)	(76)
Total cash and cash equivalents and investment debt securities, Gross Unrealized Losses	(83)
Total investments, Fair Value	318,237	411,516
Total cash and cash equivalents and investment debt securities, Fair Value	411,183	469,667
Commercial Paper [Member]
Cash and cash equivalents:
Cash and cash equivalents, Fair Value	2
Investment Debt Securities Abstract
Total investments, Amortized Cost	57,676	55,460
Total cash and cash equivalents and investment debt securities, Amortized Cost	2
Allowance for Credit Losses	0
Total investments, Gross Unrealized Gains	5	6
Total investments, Gross Unrealized Losses	(6)	(9)
Total investments, Fair Value	57,675	55,457
Corporate Debt Securities [Member]
Investment Debt Securities Abstract
Total investments, Amortized Cost	260,444	355,597
Allowance for Credit Losses	0
Total investments, Gross Unrealized Gains	195	529
Total investments, Gross Unrealized Losses	(77)	(67)
Total investments, Fair Value	260,562	356,059
US Treasury Securities [Member]
Cash and cash equivalents:
Cash and cash equivalents, Fair Value	5
Investment Debt Securities Abstract
Total cash and cash equivalents and investment debt securities, Amortized Cost	5
Cash and Money Market Funds [Member]
Cash and cash equivalents:
Cash and Cash Equivalents, Amortized Cost	85,946	$ 58,151
Cash and cash equivalents, Fair Value	85,946
Investment Debt Securities Abstract
Allowance for Credit Losses	$ 0

Cash, Cash Equivalents, and Inv

Cash, Cash Equivalents, and Investments (Available-for-sale Securities, Continuous Unrealized Loss Position, Fair Value) (Details) - USD ($) $ in Thousands	Mar. 31, 2021	Dec. 31, 2020
Total available for sale securities, Less than 12 months, Fair Value	$ 154,942	$ 176,046
Total available for sale securities Less than 12 months, Gross Unrealized Holding Losses	(83)	(76)
Total available for sale securities, More than 12 months, Fair Value	0	0
Total available for sale securities more than 12 months, Gross Unrealized Holding Losses	0	0
Available-for-sale securities, Total Fair Value	154,942	176,046
Available-for-sale securities, Total Gross Unrealized Losses	(83)	(76)
Commercial Paper [Member]
Total available for sale securities, Less than 12 months, Fair Value	23,184	32,970
Total available for sale securities Less than 12 months, Gross Unrealized Holding Losses	(6)	(9)
Total available for sale securities, More than 12 months, Fair Value	0	0
Total available for sale securities more than 12 months, Gross Unrealized Holding Losses	0	0
Available-for-sale securities, Total Fair Value	23,184	32,970
Available-for-sale securities, Total Gross Unrealized Losses	(6)	(9)
Corporate Debt Securities [Member]
Total available for sale securities, Less than 12 months, Fair Value	131,758	143,076
Total available for sale securities Less than 12 months, Gross Unrealized Holding Losses	(77)	(67)
Total available for sale securities, More than 12 months, Fair Value	0	0
Total available for sale securities more than 12 months, Gross Unrealized Holding Losses	0	0
Available-for-sale securities, Total Fair Value	131,758	143,076
Available-for-sale securities, Total Gross Unrealized Losses	$ (77)	$ (67)

Fair Value Measurements (Narrat

Fair Value Measurements (Narrative) (Details) - Convertible Debt [Member]	Mar. 31, 2021
Convertible Senior Notes 3.25% Due 2023 [Member]
Debt instrument, interest rate, stated percentage	3.25%
Convertible Senior Notes 2.00% Due 2026 [Member]
Debt instrument, interest rate, stated percentage	2.00%

Fair Value Measurements (Fair V

Fair Value Measurements (Fair Value, Marketable Securities Measured on Recurring and Nonrecurring Basis) (Details) - USD ($) $ in Thousands	Mar. 31, 2021	Dec. 31, 2020
Cash and cash equivalents, fair value disclosure	$ 92,946	$ 58,151
Available-for-sale securities, fair value disclosure	318,237	411,516
Total financial assets	389,441	427,008
Fair Value, Inputs, Level 1 [Member]
Total financial assets	69,204	15,492
Fair Value, Inputs, Level 2 [Member]
Total financial assets	320,237	411,516
Fair Value, Inputs, Level 3 [Member]
Total financial assets	0	0
Money Market Funds [Member]
Cash and cash equivalents, fair value disclosure	64,204	15,492
Money Market Funds [Member] | Fair Value, Inputs, Level 1 [Member]
Cash and cash equivalents, fair value disclosure	64,204	15,492
Money Market Funds [Member] | Fair Value, Inputs, Level 2 [Member]
Cash and cash equivalents, fair value disclosure	0	0
Money Market Funds [Member] | Fair Value, Inputs, Level 3 [Member]
Cash and cash equivalents, fair value disclosure	0	0
Commercial Paper [Member]
Cash and cash equivalents, fair value disclosure	2,000
Commercial Paper [Member] | Fair Value, Inputs, Level 1 [Member]
Cash and cash equivalents, fair value disclosure	0
Commercial Paper [Member] | Fair Value, Inputs, Level 2 [Member]
Cash and cash equivalents, fair value disclosure	2,000
Commercial Paper [Member] | Fair Value, Inputs, Level 3 [Member]
Cash and cash equivalents, fair value disclosure	0
Corporate Debt Securities [Member]
Available-for-sale securities, fair value disclosure	260,562	356,059
Corporate Debt Securities [Member] | Fair Value, Inputs, Level 1 [Member]
Available-for-sale securities, fair value disclosure	0	0
Corporate Debt Securities [Member] | Fair Value, Inputs, Level 2 [Member]
Available-for-sale securities, fair value disclosure	260,562	356,059
Corporate Debt Securities [Member] | Fair Value, Inputs, Level 3 [Member]
Available-for-sale securities, fair value disclosure	0	0
Commercial Paper, Not Included with Cash and Cash Equivalents [Member]
Available-for-sale securities, fair value disclosure	57,675	55,457
Commercial Paper, Not Included with Cash and Cash Equivalents [Member] | Fair Value, Inputs, Level 1 [Member]
Available-for-sale securities, fair value disclosure	0	0
Commercial Paper, Not Included with Cash and Cash Equivalents [Member] | Fair Value, Inputs, Level 2 [Member]
Available-for-sale securities, fair value disclosure	57,675	55,457
Commercial Paper, Not Included with Cash and Cash Equivalents [Member] | Fair Value, Inputs, Level 3 [Member]
Available-for-sale securities, fair value disclosure	0	$ 0
US Treasury Securities [Member]
Cash and cash equivalents, fair value disclosure	5,000
US Treasury Securities [Member] | Fair Value, Inputs, Level 1 [Member]
Cash and cash equivalents, fair value disclosure	5,000
US Treasury Securities [Member] | Fair Value, Inputs, Level 2 [Member]
Cash and cash equivalents, fair value disclosure	0
US Treasury Securities [Member] | Fair Value, Inputs, Level 3 [Member]
Cash and cash equivalents, fair value disclosure	$ 0

Fair Value Measurements (Schedu

Fair Value Measurements (Schedule of Available for Sale Securities Debt Maturities) (Details) - USD ($) $ in Thousands	Mar. 31, 2021	Dec. 31, 2020
Fair Value Measurements [Abstract]
Due in one year or less	$ 285,229	$ 328,077
Due after one year through two years	33,008	83,439
Total investment debt securities	$ 318,237	$ 411,516

Fixed Assets, Net (Fixed Assets

Fixed Assets, Net (Fixed Assets Stated at Cost) (Details) - USD ($) $ in Thousands	3 Months Ended
	Mar. 31, 2021	Dec. 31, 2020
Fixed assets	$ 23,246	$ 23,203
Less: accumulated depreciation	(17,759)	(16,877)
Fixed assets, net	5,487	6,326
Office Equipment [Member]
Fixed assets	$ 5,369	5,364
Property, Plant and Equipment, Useful Life	3 years
Leasehold Improvements [Member]
Fixed assets	$ 13,269	13,237
Property, Plant and Equipment, Estimated Useful Lives	Shorter of remaining lease term or useful life
Furniture and Fixtures [Member]
Fixed assets	$ 4,608	$ 4,602
Property, Plant and Equipment, Useful Life	7 years

Inventory (Schedule of Inventor

Inventory (Schedule of Inventory) (Details) - USD ($) $ in Thousands	Mar. 31, 2021	Dec. 31, 2020
Inventory [Abstract]
Work-in-process	$ 8,463	$ 8,394
Finished goods	529	633
Inventory	$ 8,992	$ 9,027

Leases (Details)

Leases (Details) - USD ($) $ in Thousands	3 Months Ended
	Mar. 31, 2021	Mar. 31, 2020
Leases [Abstract]
Operating leases, weighted-average remaining term	2 years 8 months 12 days
Operating leases, weighted-average discount rate	5.10%
Cash payments included in the measurement of the Company's lease liabilities	$ 2,200	$ 1,800
Right-of-use asset obtained in exchange for new operating lease obligations	$ 0	1,006
Increase (decrease) in operating lease liability		$ 1,000

Leases (Assets and Liabilities)

Leases (Assets and Liabilities) (Details) - USD ($) $ in Thousands	Mar. 31, 2021	Dec. 31, 2020
Leases [Abstract]
Operating lease assets	$ 11,161	$ 12,327
Other assets - extensible list location	us-gaap:OtherAssets	us-gaap:OtherAssets
Total leased assets	$ 11,161	$ 12,327
Operating lease liabilities, current	$ 7,348	$ 7,248
Accounts payable, accrued expenses and other liabilities - extensible list location	us-gaap:AccountsPayableAndOtherAccruedLiabilities	us-gaap:AccountsPayableAndOtherAccruedLiabilities
Operating lease liabilities, Noncurrent	$ 5,762	$ 7,684
Long-term other liabilities - extensible list location	Long-term other liabilities	Long-term other liabilities
Total operating lease liabilities	$ 13,110	$ 14,932

Leases (Lease Cost, Term and Di

Leases (Lease Cost, Term and Discount Rate) (Details) - USD ($) $ in Thousands	3 Months Ended
	Mar. 31, 2021	Mar. 31, 2020
Lease Cost
Net lease cost	$ 2,705	$ 2,287
Selling, General and Administrative Expenses [Member]
Lease Cost
Operating lease cost	1,685	1,739
Short-term lease cost	639	421
Variable lease cost	381	247
Other income, net
Lease Cost
Sublease income	$ 0	$ (120)

Leases (Maturities of Operating

Leases (Maturities of Operating Lease Liabilities and lease payments) (Details) - USD ($) $ in Thousands	Mar. 31, 2021	Dec. 31, 2020
Maturity of Lease Liabilities
2021 (remaining)	$ 5,877
2022	3,613
2023	2,149
2024	1,616
2025	1,032
Thereafter	0
Total lease payments	14,287
Less: Present value discount	(1,177)
Total operating lease liabilities	$ 13,110	$ 14,932

Accounts Payable, Accrued Exp_3

Accounts Payable, Accrued Expenses and Other Liabilities (Schedule of Accounts Payable and Accrued Liabilities) (Details) - USD ($) $ in Thousands	3 Months Ended
	Mar. 31, 2021	Dec. 31, 2020	Jun. 30, 2020
Accounts payable	$ 12,583	$ 24,594
Accrued employee compensation	15,629	27,154
Accrued contracted services	53,776	62,425
Accrued restructuring	652	2,504
Accrued rebates, discounts and other incentives	41,905	38,172
Operating lease liabilities	7,348	7,248
Other liabilities	8,890	8,942
Accounts payable, accrued expenses and other liabilities	140,783	171,039
Deferred income tax liability, currency translation	1,100
Europe [Member]
Accrued rebates, discounts and other incentives	$ 28,900	$ 27,400
Her Majesty's Revenue and Customs (HMRC) [Member] | Foreign Tax Authority [Member]
Percentage of credit eligible from tax authority	33.40%
Deferred income tax liability	$ 9,400		$ 9,400

Long-Term Debt (Narrative) (Det

Long-Term Debt (Narrative) (Details)	May 14, 2019USD ($)$ / shares	Jul. 06, 2016USD ($)$ / shares	Mar. 31, 2021USD ($)item	Mar. 31, 2020USD ($)	Dec. 31, 2020USD ($)	Jun. 30, 2016$ / shares
Payments for capped call transactions and associated costs		$ 38,400,000
Cap price of capped call transaction | $ / shares						$ 262.2725
Long-term debt			$ 568,114,000		$ 560,582,000
Convertible Debt [Member]
Debt Related Commitment Fees and Debt Issuance Costs			19,000,000
Cash payments for interest			7,500,000	$ 7,500,000
Interest payable, current			5,500,000		8,100,000
Debt issuance costs			$ 10,000,000		10,700,000
Convertible Senior Notes 3.25% Due 2023 [Member] | Convertible Debt [Member]
Debt instrument, face amount		460,000,000
Debt instrument, interest rate, stated percentage			3.25%
Proceeds from convertible debt		447,600,000
Debt Related Commitment Fees and Debt Issuance Costs		$ 12,400,000
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			$ 334,400,000
Debt instrument, unamortized discount, noncurrent			113,100,000
Fair value of the Convertible Notes			$ 380,700,000		363,700,000
Convertible Senior Notes 3.25% Due 2023 [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% Due 2023 [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% Due 2023 [Member] | Convertible Debt [Member] | Ninety Eight Percent Applicable Conversion Price [Member]
Debt instrument convertible consecutive trading days | item			5
Convertible Senior Notes 2.00% Due 2026 [Member] | Convertible Debt [Member]
Debt instrument, face amount	$ 230,000,000
Debt instrument, interest rate, stated percentage			2.00%
Proceeds from convertible debt	223,400,000
Debt Related Commitment Fees and Debt Issuance Costs	$ 6,600,000
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	9.2123
Debt instrument, convertible, conversion price | $ / shares	$ 108.55
Percentage of repurchase price is equal to principal amount of convertible notes			100.00%
Debt instrument liability component effective interest rate			9.90%
Long-term debt			$ 137,500,000
Debt instrument, unamortized discount, noncurrent			85,900,000
Underwriting discounts and estimated offering expenses			6,600,000
Equity issuance cost			2,500,000
Debt issuance costs			4,100,000
Fair value of the Convertible Notes			$ 146,800,000		$ 142,800,000
Convertible Senior Notes 2.00% Due 2026 [Member] | Convertible Debt [Member] | One Hundred Thirty Percent Applicable Conversion Price [Member] | Maximum [Member]
Debt instrument convertible consecutive trading days			30
Convertible Senior Notes 2.00% Due 2026 [Member] | Convertible Debt [Member] | One Hundred Thirty Percent Applicable Conversion Price [Member] | Minimum [Member]
Debt instrument convertible consecutive trading days			20
Convertible Senior Notes 2.00% Due 2026 [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 and Interest Expense) (Details) - USD ($) $ in Thousands	3 Months Ended
	Mar. 31, 2021	Mar. 31, 2020	Dec. 31, 2020
Long-term debt, gross	$ 690,000		$ 690,000
Less: Unamortized debt discounts and fees	(121,886)		(129,418)
Long-term Debt, Total	568,114		560,582
Long-term debt outstanding	568,114		560,582
Interest Expense, Long-term Debt [Abstract]
Contractual interest expense	4,887	$ 4,887
Amortization of debt discount	6,861	6,276
Amortization of debt issuance costs	671	614
Total interest expense	12,419	$ 11,777
Convertible Senior Notes 3.25% Due 2023 [Member]
Long-term debt, gross	460,000		460,000
Convertible Senior Notes 3.25% Due 2023 [Member] | Convertible Debt [Member]
Long-term debt outstanding	334,400
Convertible Senior Notes 2.00% Due 2026 [Member]
Long-term debt, gross	230,000		$ 230,000
Convertible Senior Notes 2.00% Due 2026 [Member] | Convertible Debt [Member]
Long-term debt outstanding	$ 137,500

Product Revenue, Net (Narrative

Product Revenue, Net (Narrative) (Details) - USD ($) $ in Thousands	3 Months Ended
	Mar. 31, 2021	Mar. 31, 2020
Product revenue, net	$ 81,661	$ 72,652
Product [Member]
Product revenue, net	$ 81,661	$ 72,652

Product Revenue, Net (Schedule

Product Revenue, Net (Schedule of Product Revenue, Net) (Details) - USD ($) $ in Thousands	3 Months Ended
	Mar. 31, 2021	Mar. 31, 2020
Disaggregation of Revenue [Line Items]
Product revenue, net	$ 81,661	$ 72,652
Product [Member]
Disaggregation of Revenue [Line Items]
Product revenue, net	81,661	72,652
Product [Member] | United States [Member]
Disaggregation of Revenue [Line Items]
Product revenue, net	57,299	50,779
Product [Member] | Non-US [Member]
Disaggregation of Revenue [Line Items]
Product revenue, net	$ 24,362	$ 21,873

Product Revenue, Net (Allowance

Product Revenue, Net (Allowance for credit losses) (Details) $ in Thousands	3 Months Ended
	Mar. 31, 2021USD ($)
Allowance for credit losses, Rollforward
Balance at the beginning of period	$ 235
Provision for credit losses	0
Write-offs	(37)
Balance at the end of period	$ 198

Restructuring Expenses (Narrati

Restructuring Expenses (Narrative) (Details) $ in Thousands	1 Months Ended	3 Months Ended
	Sep. 30, 2020employee	Mar. 31, 2021USD ($)	Mar. 31, 2020USD ($)
Restructuring Expenses
Workforce reduction percent	25.00%
Workforce reduction number of employees | employee	170
Restructuring charges		$ 161	$ 0
Restructuring costs accumulated		$ 14,800

Restructuring Expenses (Schedul

Restructuring Expenses (Schedule of restructuring activities) (Details) - USD ($) $ in Thousands	3 Months Ended
	Mar. 31, 2021	Mar. 31, 2020
Restructuring Cost and Reserve [Line Items]
Restructuring charges	$ 161	$ 0
Employee Compensation Restructuring Cost [Member]
Restructuring Cost and Reserve [Line Items]
Restructuring charges	157
Employee Equity Compensation Restructuring Cost [Member]
Restructuring Cost and Reserve [Line Items]
Restructuring charges	$ 4

Restructuring Expenses (Sched_2

Restructuring Expenses (Schedule of restructuring rollforward) (Details) $ in Thousands	3 Months Ended
	Mar. 31, 2021USD ($)
Restructuring Expenses
Accrued balance , Beginning Balance	$ 2,504
Charges incurred	180
Cash payments made	(1,681)
Other reserve adjustments	(351)
Accrued balance , Ending Balance	$ 652

Stock Compensation (Narrative)

Stock Compensation (Narrative) (Details) - USD ($) $ / shares in Units, $ in Thousands	Jan. 01, 2019	Oct. 31, 2012	Mar. 31, 2021	Mar. 31, 2020
Granted - Number of Shares			836,000
Granted - Weighted Average Fair Value			$ 31.66
Net proceeds from exercise of stock options			$ 0	$ (1,783)
Granted - Shares			691,000
Forfeited			182,000
2012 Stock Plan [Member]
Additional shares available	1,211,533	555,843
Stock Options [Member]
Share-based compensation not yet recognized			$ 37,900
Share-based compensation not yet recognized, period			1 year 7 months 17 days
Restricted and Performance Stock Units and Awards [Member]
Share-based compensation not yet recognized, other than options			$ 48,600
Share-based compensation not yet recognized, period			1 year 9 months 3 days
Performance Stock Units and Awards [Member]
Performance period			3 years
Share based compensation expenses			$ 400
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%
Performance Stock Units (PSUs) [Member]
Shares granted during period for stock based compensation			163,600
Forfeited			23,900

Stock Compensation (Schedule of

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, 2021	Mar. 31, 2020
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Volatility, minimum	65.20%	61.90%
Volatility, maximum	65.90%	87.10%
Expected term (in years)	6 years
Risk-free interest rate, minimum	0.40%	0.90%
Risk-free interest rate, maximum	0.70%	1.70%
Expected dividend yield	0.00%	0.00%
Minimum [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Expected term (in years)		6 years

Stock Compensation (Schedule _2

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, 2021	Dec. 31, 2020
Stock Compensation [Abstract]
Beginning Outstanding, Number of Shares	2,199
Granted - Number of Shares	836
Exercised - Number of Shares	0
Forfeited - Number of Shares	(159)
Expired - Number of Shares	(118)
Ending Outstanding, Number of Shares	2,758	2,199
Expected to vest - Number of shares	1,341
Exercisable - Number of Shares	1,417
Beginning Outstanding, Weighted Average Exercise Price	$ 96.92
Granted - Weighted Average Exercise Price	29.99
Exercised - Weighted Average Exercise Price	0
Forfeited - Weighted Average Exercise Price	70.18
Expired - Weighted Average Exercise Price	94.33
Ending Outstanding, Weighted Average Exercise Price	78.30	$ 96.92
Expected to vest - Weighted Average Exercise Price	53.33
Exercisable - Weighted Average Exercise Price	$ 101.93
Options Outstanding - Weighted Average Remaining Life	7 years 6 months	6 years 10 months 24 days
Expected to vest - Weighted Average Remaining Term	9 years 1 month 6 days
Exercisable - Weighted Average Remaining Term	6 years
Options Outstanding - Aggregate Intrinsic Value	$ 118	$ 146
Expected to vest - Aggregate Intrinsic Value	32
Exercisable - Aggregate Intrinsic Value	$ 86

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, 2021$ / sharesshares
Stock Compensation [Abstract]
Outstanding, December 31, 2019 | shares	799
Granted - Shares | shares	691
Vested - Shares | shares	(70)
Forfeited - Shares | shares	(182)
Outstanding, September 30, 2020 | shares	1,238
Outstanding - Weighted Average Fair Value, December 31, 2019 | $ / shares	$ 72.43
Granted - Weighted Average Fair Value | $ / shares	31.66
Vested - Weighted Average Fair Value | $ / shares	64.75
Forfeited - Weighted Average Fair Value | $ / shares	69.06
Outstanding - Weighted Average Fair Value, September 30, 2020 | $ / shares	$ 50.64

Stock Compensation (Schedule _4

Stock Compensation (Schedule of Stock Based Compensation Expense) (Details) - USD ($) $ in Thousands	3 Months Ended
	Mar. 31, 2021	Mar. 31, 2020
Employee Service Share-based Compensation, Allocation of Recognized Period Costs [Line Items]
Allocated stock-based compensation	$ 8,419	$ 12,473
Selling, General and Administrative Expenses [Member]
Employee Service Share-based Compensation, Allocation of Recognized Period Costs [Line Items]
Allocated stock-based compensation	6,389	9,723
Research and Development Expense [Member]
Employee Service Share-based Compensation, Allocation of Recognized Period Costs [Line Items]
Allocated stock-based compensation	2,026	2,750
Restructuring Charges [Member]
Employee Service Share-based Compensation, Allocation of Recognized Period Costs [Line Items]
Allocated stock-based compensation	$ 4	$ 0

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, 2021	Mar. 31, 2020
Antidilutive securities excluded from computation of earnings per share, amount	8,360	7,752
Convertible Notes [Member]
Antidilutive securities excluded from computation of earnings per share, amount	4,435	4,435
Stock Options [Member]
Antidilutive securities excluded from computation of earnings per share, amount	2,730	2,446
Restricted Stock Units (RSUs) [Member]
Antidilutive securities excluded from computation of earnings per share, amount	1,195	871