Vericel (VCEL) 10-Q 5 Aug 20 2020 Q2 Quarterly report Financial data

Cover Page

Cover Page - shares	6 Months Ended
	Jun. 30, 2020	Jul. 31, 2020
Cover [Abstract]
Document Type	10-Q
Document Quarterly Report	true
Document Period End Date	Jun. 30, 2020
Document Transition Report	false
Entity File Number	001-35280
Entity Registrant Name	VERICEL CORPORATION
Entity Incorporation, State or Country Code	MI
Entity Tax Identification Number	94-3096597
Entity Address, Address Line One	64 Sidney Street
Entity Address, City or Town	Cambridge
Entity Address, State or Province	MA
Entity Address, Postal Zip Code	02139
City Area Code	617
Local Phone Number	588-5555
Title of 12(b) Security	Common Stock (No par value)
Trading Symbol	VCEL
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		45,250,402
Entity Central Index Key	0000887359
Current Fiscal Year End Date	--12-31
Document Fiscal Year Focus	2020
Document Fiscal Period Focus	Q2
Amendment Flag	false

CONDENSED CONSOLIDATED BALANCE

CONDENSED CONSOLIDATED BALANCE SHEETS - USD ($) $ in Thousands	Jun. 30, 2020	Dec. 31, 2019
Current assets:
Cash and cash equivalents	$ 55,704	$ 26,889
Short term investments	25,086	42,829
Accounts receivable (net of allowance for doubtful accounts of $207 and $306, respectively)	23,655	32,168
Inventory	8,417	6,816
Other current assets	2,900	2,953
Total current assets	115,762	111,655
Property and equipment, net	7,040	7,144
Restricted cash	89	89
Right-of-use leased assets	23,800	25,103
Long term investments	0	9,247
Total assets	146,691	153,238
Current liabilities:
Accounts payable	4,535	6,345
Accrued expenses	7,975	7,948
Current portion of operating lease liabilities	5,570	5,461
Other liabilities	41	41
Total current liabilities	18,121	19,795
Operating lease liabilities	20,881	22,242
Other long-term liabilities	93	110
Total liabilities	39,095	42,147
COMMITMENTS AND CONTINGENCIES
Shareholders’ equity:
Common stock, no par value; shares authorized — 75,000; shares issued and outstanding — 45,194 and 44,864, respectively	499,103	489,749
Other comprehensive gain	146	21
Accumulated deficit	(391,653)	(378,679)
Total shareholders’ equity	107,596	111,091
Total liabilities and shareholders’ equity	$ 146,691	$ 153,238

CONDENSED CONSOLIDATED BALANC_2

CONDENSED CONSOLIDATED BALANCE SHEETS (Parenthetical) - USD ($) $ in Thousands	Jun. 30, 2020	Dec. 31, 2019
Statement of Financial Position [Abstract]
Allowance for doubtful accounts	$ 207	$ 306
Common stock, shares authorized (in shares)	75,000,000	75,000,000
Common stock, shares issued (in shares)	45,194,000	44,864,000
Common stock, shares outstanding (in shares)	45,194,000	44,864,000

CONDENSED CONSOLIDATED STATEMEN

CONDENSED CONSOLIDATED STATEMENTS OF OPERATIONS - USD ($) shares in Thousands, $ in Thousands	3 Months Ended		6 Months Ended
	Jun. 30, 2020	Jun. 30, 2019	Jun. 30, 2020	Jun. 30, 2019
Income Statement [Abstract]
Product sales, net	$ 20,014	$ 26,151	$ 46,692	$ 47,961
Revenue, Product and Service [Extensible List]			us-gaap:ProductMember
Cost of product sales	8,660	9,022	$ 18,582	17,662
Cost, Product and Service [Extensible List]			us-gaap:ProductMember
Gross profit	11,354	17,129	$ 28,110	30,299
Research and development	3,226	21,070	6,989	24,078
Selling, general and administrative	16,486	16,259	34,555	29,779
Total operating expenses	19,712	37,329	41,544	53,857
Loss from operations	(8,358)	(20,200)	(13,434)	(23,558)
Other income (expense):
Interest income	147	428	453	908
Other income (expense)	(1)	(2)	(3)	(4)
Interest expense	(57)	(18)	10	18
Total other income (expense)	89	408	460	922
Net loss	$ (8,269)	$ (19,792)	$ (12,974)	$ (22,636)
Net loss per share attributable to common shareholders (Basic and Diluted) (in dollars per share)	$ (0.18)	$ (0.45)	$ (0.29)	$ (0.52)
Weighted average number of common shares outstanding (Basic and Diluted) (in shares)	45,137	43,956	45,031	43,841

CONDENSED CONSOLIDATED STATEM_2

CONDENSED CONSOLIDATED STATEMENTS OF COMPREHENSIVE LOSS - USD ($) $ in Thousands	3 Months Ended		6 Months Ended
	Jun. 30, 2020	Jun. 30, 2019	Jun. 30, 2020	Jun. 30, 2019
Statement of Comprehensive Income [Abstract]
Net loss	$ (8,269)	$ (19,792)	$ (12,974)	$ (22,636)
Other comprehensive loss:
Unrealized gain on investments	84	35	125	38
Comprehensive loss	$ (8,185)	$ (19,757)	$ (12,849)	$ (22,598)

CONSOLIDATED STATEMENTS OF SHAR

CONSOLIDATED STATEMENTS OF SHAREHOLDERS EQUITY - USD ($) shares in Thousands, $ in Thousands	Total	Common Stock	Warrants	Accumulated Other Comprehensive Income (Loss)	Accumulated Deficit
Beginning balance (in shares) at Dec. 31, 2018		43,578
Beginning balance at Dec. 31, 2018	$ 102,231	$ 471,180	$ 104	$ (39)	$ (369,014)
Increase (Decrease) in Shareholders' Equity
Net loss	(2,844)				(2,844)
Compensation expense related to stock options and restricted stock units granted, net of forfeitures	2,628	$ 2,628
Stock option exercises (in shares)		228
Stock option exercises	780	$ 780
Shares issued under the Employee Stock Purchase Plan (in shares)		19
Shares issued under the Employee Stock Purchase Plan	218	$ 218
Unrealized gain on investments	42			42
Ending balance (in shares) at Mar. 31, 2019		43,825
Ending balance at Mar. 31, 2019	103,055	$ 474,806	104	3	(371,858)
Beginning balance (in shares) at Dec. 31, 2018		43,578
Beginning balance at Dec. 31, 2018	102,231	$ 471,180	104	(39)	(369,014)
Increase (Decrease) in Shareholders' Equity
Net loss	(22,636)
Unrealized gain on investments	38
Ending balance (in shares) at Jun. 30, 2019		44,066
Ending balance at Jun. 30, 2019	88,542	$ 480,050	104	38	(391,650)
Beginning balance (in shares) at Mar. 31, 2019		43,825
Beginning balance at Mar. 31, 2019	103,055	$ 474,806	104	3	(371,858)
Increase (Decrease) in Shareholders' Equity
Net loss	(19,792)				(19,792)
Compensation expense related to stock options and restricted stock units granted, net of forfeitures	4,183	$ 4,183
Stock option exercises (in shares)		227
Stock option exercises	850	$ 850
Shares issued under the Employee Stock Purchase Plan (in shares)		14
Shares issued under the Employee Stock Purchase Plan	211	$ 211
Unrealized gain on investments	35			35
Ending balance (in shares) at Jun. 30, 2019		44,066
Ending balance at Jun. 30, 2019	88,542	$ 480,050	104	38	(391,650)
Beginning balance (in shares) at Dec. 31, 2019		44,864
Beginning balance at Dec. 31, 2019	111,091	$ 489,749	0	21	(378,679)
Increase (Decrease) in Shareholders' Equity
Net loss	(4,705)				(4,705)
Compensation expense related to stock options and restricted stock units granted, net of forfeitures	3,768	$ 3,768
Stock option exercises (in shares)		57
Stock option exercises	196	$ 196
Shares issued under the Employee Stock Purchase Plan (in shares)		20
Shares issued under the Employee Stock Purchase Plan	224	$ 224
Issuance of stock upon restricted stock unit vesting (in shares)		36
Issuance of stock upon restricted stock unit vesting	0
Restricted stock withheld for employee tax remittance (in shares)		(14)
Restricted stock withheld for employee tax remittance	(163)	$ (163)
Unrealized gain on investments	41			41
Ending balance (in shares) at Mar. 31, 2020		44,963
Ending balance at Mar. 31, 2020	110,452	$ 493,774	0	62	(383,384)
Beginning balance (in shares) at Dec. 31, 2019		44,864
Beginning balance at Dec. 31, 2019	111,091	$ 489,749	0	21	(378,679)
Increase (Decrease) in Shareholders' Equity
Net loss	(12,974)
Unrealized gain on investments	125
Ending balance (in shares) at Jun. 30, 2020		45,194
Ending balance at Jun. 30, 2020	107,596	$ 499,103	0	146	(391,653)
Beginning balance (in shares) at Mar. 31, 2020		44,963
Beginning balance at Mar. 31, 2020	110,452	$ 493,774	0	62	(383,384)
Increase (Decrease) in Shareholders' Equity
Net loss	(8,269)				(8,269)
Compensation expense related to stock options and restricted stock units granted, net of forfeitures	4,376	$ 4,376
Stock option exercises (in shares)		188
Stock option exercises	696	$ 696
Shares issued under the Employee Stock Purchase Plan (in shares)		32
Shares issued under the Employee Stock Purchase Plan	257	$ 257
Issuance of stock upon restricted stock unit vesting (in shares)		11
Issuance of stock upon restricted stock unit vesting	0
Unrealized gain on investments	84			84
Ending balance (in shares) at Jun. 30, 2020		45,194
Ending balance at Jun. 30, 2020	$ 107,596	$ 499,103	$ 0	$ 146	$ (391,653)

CONDENSED CONSOLIDATED STATEM_3

CONDENSED CONSOLIDATED STATEMENTS OF CASH FLOWS - USD ($) $ in Thousands	6 Months Ended
	Jun. 30, 2020	Jun. 30, 2019
Operating activities:
Net loss	$ (12,974)	$ (22,636)
Adjustments to reconcile net loss to net cash provided by (used for) operating activities:
Depreciation and amortization expense	1,079	698
Stock compensation expense	8,144	6,810
Foreign currency translation loss	45	13
Loss on sale of fixed assets	30	0
Amortization of premiums and discounts on marketable securities	(25)	(408)
Amortization and interest accretion related to operating leases	1,603	1,139
Changes in operating assets and liabilities:
Inventory	(1,601)	(1,230)
Accounts receivable	8,513	2,370
Prepaid and other current assets	53	680
Accounts payable	(1,692)	(2,238)
Accrued expenses	27	(2,229)
Operating lease liabilities	(1,537)	(1,007)
Other non-current assets and liabilities, net	0	(187)
Net cash provided by (used for) operating activities	1,665	(18,225)
Investing activities:
Purchases of short term investments	(5,657)	(32,402)
Maturities of short term investments	32,797	45,477
Expenditures for property, plant and equipment	(1,186)	(1,224)
Net cash provided by investing activities	25,954	11,851
Financing activities:
Net proceeds from common stock issuance due to stock option exercises	1,373	2,059
Payments on employee's behalf for taxes related to vesting of restricted stock unit awards	(163)	0
Other	(14)	(9)
Net cash provided by financing activities	1,196	2,050
Net increase in cash, cash equivalents, and restricted cash	28,815	(4,324)
Cash, cash equivalents, and restricted cash at beginning of period	26,978	18,286
Cash, cash equivalents, and restricted cash at end of period	$ 55,793	$ 13,962

Organization

Organization	6 Months Ended
	Jun. 30, 2020
Organization, Consolidation and Presentation of Financial Statements [Abstract]
Organization	Organization Vericel Corporation, a Michigan corporation (together with its consolidated subsidiaries referred to herein as the Company, Vericel, we, us or our), was incorporated in March 1989 and began employee-based operations in 1991. The Company is a fully-integrated, commercial-stage biopharmaceutical company and is a leader in advanced cell therapies for the sports medicine and severe burn care markets. Vericel currently markets two cell therapy products, MACI ® and Epicel ® , in the United States. Vericel obtained both products in May 2014, as part of the acquisition of certain assets and the assumption of certain liabilities from Sanofi, a French société anonyme (Sanofi). MACI ® (autologous cultured chondrocytes on porcine collagen membrane) is an autologous cellularized scaffold product indicated for the repair of symptomatic, single or multiple full-thickness cartilage defects of the knee with or without bone involvement in adults. The Company also markets Epicel ® (cultured epidermal autografts), a permanent skin replacement Humanitarian Use Device (HUD) for the treatment of adult and pediatric patients with deep-dermal or full-thickness burns comprising greater than or equal to 30 percent of total body surface area (TBSA). The Company operates its business primarily in the U.S. in one reportable segment — the research, product development, manufacture and distribution of biopharmaceuticals for use in the treatment of specific diseases. COVID-19 The novel coronavirus (COVID-19) outbreak was first reported by China in late December 2019 and rapidly spread globally. The World Health Organization (WHO) declared the outbreak a pandemic on March 11, 2020 and the President of the United States declared a national health emergency two days later. Subsequently most states' governments, including those in Massachusetts and Michigan where the Company's operations are located, issued orders requiring businesses that do not conduct essential services to temporarily close their physical workplaces to employees and customers. The status of such orders varies on a state-by-state basis and is likely to continue to vary. Because Vericel is deemed an essential business, the Company is exempt from these state orders in their current form. Notwithstanding being an essential business, the Company’s business and operations have been, and are expected to continue to be, adversely impacted by the effects of COVID-19 as a result of various factors including, without limitation, patients’ potential reluctance to undergo elective surgical procedures, healthcare facility restrictions regarding elective surgical procedures, the recent economic downturn due to the pandemic, the imposition of related public health measures and travel and business restrictions and disruptions to the ability of the Company’s employees to perform their jobs. The implantation of MACI is an elective surgical procedure. On March 13, 2020 and March 14, 2020, the American College of Surgeons and United States Surgeon General, respectively, recommended that each hospital, health system, and surgeon minimize, postpone, or cancel electively scheduled surgeries, which has resulted in a reduction in MACI sales. The stated purpose for these recommendations was that every elective surgery could spread COVID-19 within a facility, use up personal protective equipment (PPE) which may be needed by healthcare workers treating COVID-19 patients, and burden hospital workforce who may be needed to respond to COVID-19. These recommendations were followed by numerous state level executive orders either banning or partially banning elective surgeries. As a result of these restrictions, beginning in mid-March 2020, the Company started to experience a significant increase in cancellations of scheduled MACI procedures as well as a slowdown in new MACI orders. By early April 2020, 45 states, representing over 95% of total U.S. surgical capacity had issued either mandates or recommendations and guidelines suspending elective surgical procedures. These restrictions began to ease in May and, by the end of June 2020, states representing an estimated 90% total U.S. surgical capacity had lifted restrictions suspending elective procedures. It is likely that restrictions will continue to be both lifted and re-imposed as regional COVID 19 cases rates fall and rise. The Company’s MACI business will continue to be negatively impacted so long as multiple state orders and/or facilities restrict elective surgical procedures. Going Concern The accompanying condensed consolidated financial statements have been prepared on a basis which assumes that the Company will continue as a going concern and contemplates the realization of assets and the satisfaction of liabilities and commitments in the normal course of business. As of June 30, 2020, the Company had an accumulated deficit of $391.7 million and incurred a net loss of $8.3 million and $13.0 million for the three and six months ended June 30, 2020, respectively. The Company had cash and cash equivalents of $55.8 million and investments of $25.1 million as of June 30, 2020. The Company expects that existing cash, cash equivalents and investments will be sufficient to support the Company’s current operations through at least 12 months from the issuance of these financial statements. However, the continuing effects of the COVID-19 pandemic may require the Company to engage in layoffs, furloughs and/or reductions in salary, all of which may result in irrecoverable losses of customers and significantly impact long-term liquidity. If elective surgery restrictions are reinstated on a widespread basis, significantly impacting the Company's business, the Company may need to a ccess additional capital; however, the Company may not be able to obtain financing on acceptable terms or at all, particularly in light of the impact of COVID-19 on the global economy and financial markets. The terms of any financing may adversely affect the holdings or the rights of the Company’s shareholders.

Basis of Presentation

Basis of Presentation	6 Months Ended
	Jun. 30, 2020
Accounting Policies [Abstract]
Basis of Presentation	Basis of Presentation The accompanying condensed consolidated financial statements as of June 30, 2020 and for the three and six months ended June 30, 2020 are unaudited and have been prepared in accordance with the rules and regulations of the U.S. Securities and Exchange Commission (SEC). The preparation of condensed consolidated financial statements in conformity with generally accepted accounting principles in U.S. GAAP requires management to make estimates, judgments, and assumptions that may affect the reported amounts of assets, liabilities, equity, revenues and expenses. Certain information and footnote disclosures normally included in financial statements prepared in accordance with U.S. GAAP have been omitted pursuant to such rules and regulations. The financial statements reflect, in the opinion of management, all adjustments (consisting only of normal, recurring adjustments) necessary to state fairly the financial position and results of operations as of and for the periods indicated. We base our estimates on historical experience and on various other assumptions that we believe are reasonable, the results of which form the basis for making judgments about the carrying values of assets, liabilities and equity and the amount of revenues and expenses. The full extent to which the COVID-19 pandemic will continue to directly or indirectly impact our business, results of operations and financial condition, including sales, expenses, reserves and allowances, manufacturing, clinical trials, research and development costs and employee-related amounts, will depend on future developments that are highly uncertain, including as a result of new information that may emerge concerning COVID-19 and the actions taken to continue to contain it or treat COVID-19, as well as the economic impact on our customers. We have made estimates of the impact of COVID-19 within our financial statements and there may be changes to those estimates in future periods. Actual results may differ from these estimates. As of June 30, 2020, the Company has not recorded impairments to investments, inventory, other current assets or long-lived assets as a result of the COVID-19 pandemic and does not expect material impairments in the future. The Company has assessed the impact of COVID-19 on accounts receivables (see note 4). These condensed consolidated financial statements should be read in conjunction with the audited consolidated financial statements and the notes thereto included in our Annual Report on Form 10-K for the year ended December 31, 2019 as filed with the SEC on February 25, 2020 (Annual Report). Consolidated Statement of Cash Flows The following table presents certain supplementary cash flows information for the six months ended June 30, 2020 and 2019: Six Months Ended June 30, (In thousands) 2020 2019 Supplementary Cash Flows information: Non-cash information: Right-of-use asset and lease liability recognized $ 429 $ 560 Additions to property, plant and equipment included in accounts payable 55 365 Cash information: Interest paid (net of interest capitalized) $ 3 $ 4 Total cash, cash equivalents, and restricted cash of $55.8 million as of June 30, 2020, shown in the statement of cash flows is comprised of cash and cash equivalents of $55.7 million and restricted cash of $0.1 million which is included in other long term assets on the consolidated balance sheet. As of June 30, 2019, cash and cash equivalents were $14.0 million and the Company did not have any restricted cash.

Recent Accounting Pronouncement

Recent Accounting Pronouncements	6 Months Ended
	Jun. 30, 2020
Accounting Standards Update and Change in Accounting Principle [Abstract]
Recent Accounting Pronouncements	Recent Accounting Pronouncements Measuring Credit Losses on Financial Instruments The FASB issued updated guidance on measuring credit losses on financial instruments. The guidance removes the thresholds that companies apply to measure credit losses on financial instruments measured at amortized cost, such as loans, receivables, and held-to-maturity debt securities. Prior to the updated guidance, credit losses are recognized when it is probable that the loss has been incurred. The revised guidance removes all recognition thresholds and requires companies to recognize an allowance for credit losses for the difference between the amortized cost basis of a financial instrument and the amount of amortized cost that a company expected to collect over the instrument’s contractual life. The Accounting Standard Update (ASU) 2016-13, Financial Instruments-Credit Losses (Topic 326), became effective for the Company January 1, 2020. See note 4 and note 8 for further discussion. Fair Value Measurement Disclosure The FASB issued updated guidance through ASU 2018-13, Fair Value Measurement (Topic 820) Disclosure Framework-Changes to the Disclosure Requirements for Fair Value Measurement. The revised guidance is intended to develop a more consistent disclosure framework that will increase clarity, remove, modify and add certain fair value disclosures to improve the effectiveness of the Company’s disclosures in the notes of the financial statements. This guidance became effective for the Company January 1, 2020 and had no impact to its condensed consolidated financial statements. Simplifying the Accounting for Income Taxes In December 2019, the FASB issued ASU 2019-12, Simplifying the Accounting for Income Taxes (ASC 740). The ASU enhances and simplifies various aspects of the income tax accounting guidance in ASC 740, including requirements related to hybrid tax regimes, the tax basis step-up in goodwill obtained in a transaction that is not a business combination, separate financial statements of entities not subject to tax, the intra-period tax allocation exception to the incremental approach, ownership changes in investments, changes from a subsidiary to an equity method investment, interim-period accounting for enacted changes in tax law, and the year-to-date loss limitation in interim-period tax accounting. This guidance is effective for the Company for annual and interim periods beginning after December 31, 2020; however, early adoption is permitted. The Company is currently in the process of evaluating the impact to its condensed consolidated financial statements.

Revenue

Revenue	6 Months Ended
	Jun. 30, 2020
Risks and Uncertainties [Abstract]
Revenue	Revenue Revenue Recognition and Net Product Sales The Company recognizes product revenue from sales of MACI kits, MACI implants and Epicel grafts following the five-step model in Accounting Standards Codification 606, Revenue Recognition, (ASC 606). MACI Kits MACI kits are sold directly to hospitals based on contracted rates in the approved contract or sales order. The Company recognizes MACI kit revenue upon delivery of the biopsy kit at which time the customer (the facility) is in control of the kit. The kit provides the doctor the ability to biopsy a sampling of cells to provide to the Company that can be used later to manufacture the implant. The ordering of the kit does not obligate the Company to manufacture an implant nor does the receipt of the cell tissue. The customer’s order of an implant is separate from the process of ordering the kit. Therefore, the sale of the kit and any subsequent sale of an implant are distinct contracts and are accounted for separately. MACI Implants The Company contracts with two specialty pharmacies, Orsini Pharmaceutical Services, Inc. (Orsini) and AllCare Plus Pharmacy, Inc. (AllCare) to distribute its MACI product in arrangements whereby the Company retains the credit and collection risk from the end customer. The Company pays both specialty pharmacies a fee for each patient to whom MACI is dispensed. Both Orsini and AllCare perform collection activities to receive payment from customers. The Company has engaged a third-party to provide services in connection with a patient support program to manage patient cases and to ensure complete and correct billing information is provided to the insurers and hospitals. In addition, the Company also sells MACI directly to DMS Pharmaceutical (DMS) for military implants. The sales directly to DMS are sold at a contracted rate. Prior authorization and confirmation of coverage level by the patient’s private insurance plan, hospital or government payer is a prerequisite to the shipment of product to a patient. The Company recognizes product revenues from sales of all MACI implants upon delivery at which time the customer obtains control of the implant and the claim is billable. The total consideration which the Company expects to collect in exchange for MACI implants (the transaction price) may be fixed or variable. Direct sales to hospitals or distributors are recorded at a contracted price, and other than customary prompt pay discounts, there are typically no forms of variable consideration. When the Company sells MACI the patient is responsible for payment, however, the Company is typically reimbursed by a third-party insurer or government payer, subject to a patient co-pay amount. Reimbursements from third-party insurers and government payers vary by patient and payer and are based on either contracted rates, publicly available rates or a fee schedule. Net product revenue is recognized net of contractual allowances, which considers historical collection experience from both the payer and patient and the terms of the Company’s contractual arrangements. The Company estimates expected collections for these transactions using the portfolio approach. These estimates include the impact of contractual allowances, which considers historical collection experience from both the payer and patient, denial rates and the terms of the Company’s contractual arrangements. The Company records a reduction to revenue at the time of sale for its estimate of the amount of consideration that will not be collected. In addition, potential credit risk exposure has been evaluated for the Company's accounts receivable in accordance with ASC 326, Financial Instruments - Credit Losses. The Company assesses risk and determines a loss percentage by pooling account receivables based on similar risk characteristics. The loss percentage is based on current and historical information as well as reasonable and supportable forecasts. This loss percentage was applied to the accounts receivables as of June 30, 2020. The total allowance for uncollectible consideration was $4.4 million as of June 30, 2020 and $3.9 million at December 31, 2019. The allowance includes less than $0.1 million of which is related to COVID-19 potential impacts on accounts receivable from third-party insurers, government payers, hospitals and patients. Changes to the estimate of the amount of consideration that will not be collected could have a material impact to the revenue recognized. A 0.5% change to the estimated uncollectible percentage could result in approximately a $0.1 million decrease in the revenue recognized for the six months ended June 30, 2020. Changes in estimates of the transaction price are recorded through revenue in the period in which such change occurs. Changes in estimates related to prior period sales for the three and six months ended June 30, 2020 resulted in a decrease to revenue of $0.2 million and increase to revenue of $1.1 million, respectively, and an increase to revenue of $0.09 million and $0.05 million, respectively for the same period in 2019. The changes in estimates recorded during the three and six months ended June 30, 2020, were primarily due to completion of the billing claims process for implants that occurred in late 2019. Upon completion of the billing claims process, the Company concluded that it was probable that a significant reversal in the amount of revenue recognized would not occur. Epicel The Company sells Epicel directly to hospitals based on contracted rates stated in the approved contract or purchase order. Similar to MACI, there is no obligation to manufacture skin grafts upon receipt of a skin biopsy, and Vericel has no contractual right to receive payment until the product is delivered to the hospital. The Company recognizes product revenues from sales of Epicel upon delivery to the hospital at which time the customer is in control of the skin grafts and the claim is billable to the hospital. Revenue by Product and Customer The following table and description below shows the products from which the Company generated its revenue: Three Months Ended June 30, Six Months Ended June 30, Revenue by product (in thousands) 2020 2019 2020 2019 MACI implants and kits Implants based on contracted rate sold through a specialty pharmacy (a) $ 9,790 $ 12,989 $ 21,218 $ 22,776 Implants subject to third party reimbursement sold through a specialty pharmacy (b) 2,819 3,459 6,335 6,202 Implants sold direct based on contracted rates (c) 1,806 3,450 4,916 6,676 Implants sold direct subject to third party reimbursement (d) 589 281 1,016 603 Biopsy kits - direct bill 348 557 811 1,099 Change in estimates related to prior periods (e) (248) 87 1,095 50 Epicel Direct bill (hospital) 4,910 5,328 11,301 10,555 Total revenue $ 20,014 $ 26,151 $ 46,692 $ 47,961 (a) Represents implants sold through Orsini and AllCare in both 2020 and 2019 in which such specialty pharmacies have entered into a direct contract with the underlying insurance provider. The amount of reimbursement is based on contracted rates at the time of sale supported by the pharmacy's direct contracts. Also represents direct sales under a contract to the specialty distributor DMS. (b) Represents implants sold through Orsini or AllCare in which such specialty pharmacy does not have a direct contract with the underlying payer. The amount of reimbursement is established based on a payer or state fee schedule and/or payer history. (c) Represents implants sold directly from the Company to the facility based on a contract and known price agreed upon prior to the surgery date. (d) Represents implants sold directly from the Company to the facility based on a contract and known price agreed upon prior to the surgery date. The payment terms are subject to third-party reimbursement from an underlying insurance provider. (e) Primarily represents changes in estimates related to implants sold through Orsini or AllCare in which such specialty pharmacy does not have a direct contract with the underlying payer. The initial estimate of the amount of reimbursement is established based on a payer or state fee schedule and/or payer history. The change in estimates is a result of additional information or actual cash collections received in the current period. Concentration of Credit Risk The table below shows the Company’s total Epicel revenue and accounts receivable balances from customers whose revenue or accounts receivable concentration is greater than 10% in any of the periods disclosed below. The Company did not have MACI revenue or accounts receivable concentrations greater than 10% in any of the periods disclosed below. Revenue Concentration Accounts Receivable Concentration Three Months Ended June 30, Six Months Ended June 30, June 30, December 31, 2020 2019 2020 2019 2020 2019 Epicel 6 % 6 % 10 % 8 % 3 % 2 %

Selected Balance Sheet Componen

Selected Balance Sheet Components	6 Months Ended
	Jun. 30, 2020
Balance Sheet Related Disclosures [Abstract]
Selected Balance Sheet Components	Selected Balance Sheet Components Inventory Inventory as of June 30, 2020 and December 31, 2019: (In thousands) June 30, 2020 December 31, 2019 Raw materials $ 7,853 $ 6,085 Work-in-process 513 541 Finished goods 51 190 Inventory $ 8,417 $ 6,816 Property and Equipment Property and Equipment, net as of June 30, 2020 and December 31, 2019: (In thousands) June 30, 2020 December 31, 2019 Machinery and equipment $ 3,279 $ 3,152 Furniture, fixtures and office equipment 810 775 Computer equipment and software 6,393 6,174 Leasehold improvements 5,256 5,256 Construction in process 1,311 859 Financing right-of-use lease 129 148 Total property and equipment, gross 17,178 16,364 Less accumulated depreciation (10,138) (9,220) $ 7,040 $ 7,144 Depreciation expense for the three and six months ended June 30, 2020 was $0.5 million and $1.1 million, respectively, and $0.4 million and $0.7 million for the same periods in 2019. Accrued Expenses Accrued Expenses as of June 30, 2020 and December 31, 2019 are as follows: (In thousands) June 30, 2020 December 31, 2019 Bonus related compensation $ 2,872 $ 5,116 Employee related accruals 2,578 1,785 Other accrued expenses 2,525 1,047 Accrued expenses $ 7,975 $ 7,948

Leases

Leases	6 Months Ended
	Jun. 30, 2020
Leases [Abstract]
Leases	Leases The Company leases facilities in Ann Arbor, Michigan and Cambridge, Massachusetts. The Ann Arbor facility includes office space, and the Cambridge facility includes clean rooms, laboratories for MACI and Epicel manufacturing and office space. The Company also leases offsite warehouse space, vehicles and computer equipment. Certain of the Company’s lease agreements include lease payments that are adjusted periodically for an index or rate. The leases are initially measured using the projected payments adjusted for the index or rate in effect at the commencement date. The Company’s lease agreements do not contain any material residual value guarantees or material restrictive covenants. All operating lease commitments with a lease term greater than 12 months are recognized as right to use assets and liabilities, on a discounted basis on the balance sheet. Leases with an initial term of 12 months or less are not recorded on the balance sheet and for both the three and six months ended June 30, 2020 and 2019, lease expense of less than $0.1 million was recorded related to short-term leases. The contribution toward the cost of tenant improvements is recorded as a reduction of the operating lease assets. For the three and six months ended June 30, 2020 , the Company recognized $1.4 million and $2.9 million of operating lease expense and $1.3 million and $2.6 million for the same periods in 2019. For both the three and six months ended June 30, 2020 and 2019, the Company recognized less than $0.1 million of financing lease expense. The Company’s leases contain non-lease components and activities that do not transfer a good or service to the Company. The Company elected not to combine lease and non-lease components and therefore non-lease costs were not included in the net lease assets or lease liabilities. Total leased assets and liabilities as reassessed under the updated guidance and classified on the balance sheet, as of June 30, 2020 and December 31, 2019 are as follows: (In thousands) Classification June 30, 2020 December 31, 2019 Assets Operating Right-of-use assets $ 23,800 $ 25,103 Finance Property and equipment, net 129 148 $ 23,929 $ 25,251 Liabilities Current Operating Current portion of operating lease liabilities $ 5,570 $ 5,461 Finance Other liabilities 41 41 $ 5,611 $ 5,502 Non-current Operating Operating lease liabilities $ 20,881 $ 22,242 Finance Other long-term liabilities 93 110 $ 20,974 $ 22,352
Leases	Leases The Company leases facilities in Ann Arbor, Michigan and Cambridge, Massachusetts. The Ann Arbor facility includes office space, and the Cambridge facility includes clean rooms, laboratories for MACI and Epicel manufacturing and office space. The Company also leases offsite warehouse space, vehicles and computer equipment. Certain of the Company’s lease agreements include lease payments that are adjusted periodically for an index or rate. The leases are initially measured using the projected payments adjusted for the index or rate in effect at the commencement date. The Company’s lease agreements do not contain any material residual value guarantees or material restrictive covenants. All operating lease commitments with a lease term greater than 12 months are recognized as right to use assets and liabilities, on a discounted basis on the balance sheet. Leases with an initial term of 12 months or less are not recorded on the balance sheet and for both the three and six months ended June 30, 2020 and 2019, lease expense of less than $0.1 million was recorded related to short-term leases. The contribution toward the cost of tenant improvements is recorded as a reduction of the operating lease assets. For the three and six months ended June 30, 2020 , the Company recognized $1.4 million and $2.9 million of operating lease expense and $1.3 million and $2.6 million for the same periods in 2019. For both the three and six months ended June 30, 2020 and 2019, the Company recognized less than $0.1 million of financing lease expense. The Company’s leases contain non-lease components and activities that do not transfer a good or service to the Company. The Company elected not to combine lease and non-lease components and therefore non-lease costs were not included in the net lease assets or lease liabilities. Total leased assets and liabilities as reassessed under the updated guidance and classified on the balance sheet, as of June 30, 2020 and December 31, 2019 are as follows: (In thousands) Classification June 30, 2020 December 31, 2019 Assets Operating Right-of-use assets $ 23,800 $ 25,103 Finance Property and equipment, net 129 148 $ 23,929 $ 25,251 Liabilities Current Operating Current portion of operating lease liabilities $ 5,570 $ 5,461 Finance Other liabilities 41 41 $ 5,611 $ 5,502 Non-current Operating Operating lease liabilities $ 20,881 $ 22,242 Finance Other long-term liabilities 93 110 $ 20,974 $ 22,352

Stock-Based Compensation

Stock-Based Compensation	6 Months Ended
	Jun. 30, 2020
Share-based Payment Arrangement [Abstract]
Stock-Based Compensation	Stock-Based Compensation Stock Option, Restricted Stock Units and Equity Incentive Plans The Company has historically had various stock incentive plans and agreements that provide for the issuance of nonqualified and incentive stock options and restricted stock units as well as other equity awards. Such awards may be granted by the Company’s Board of Directors to certain of the Company’s employees, directors and consultants. Options and restricted stock units granted to employees and non-employees under these plans expire no later than ten years from the date of grant and generally become exercisable over a four The 2019 Omnibus Incentive Plan (2019 Plan) was approved on May 1, 2019 and provides incentives through the grant of stock options, stock appreciation rights, restricted stock awards and restricted stock units. The exercise price of stock options granted under the 2019 Plan shall not be less than the fair market value of the Company’s common stock on the date of grant. The 2019 Plan replaced the 1992 Stock Option Plan, the 2001 Stock Option Plan, the Amended and Restated 2004 Equity Incentive Plan, the 2009 Second Amended and Restated Omnibus Incentive Plan and the 2017 Omnibus Incentive Plan (Prior Plans), and no new grants have been granted under the Prior Plans after approval. However, the expiration or forfeiture of options previously granted under the Prior Plans will increase the number of shares available for issuance under the 2019 Plan. The Amended and Restated 2019 Omnibus Incentive Plan (Amended and Restated 2019 Plan) was approved on April 29, 2020. Amendments to the Amended and Restated 2019 Omnibus Plan included increasing the total number of shares of the Company's common stock reserved for issuance under the 2019 Plan by 2,400,000 shares, a revised ratio at which "full- value" awards are counted against the share reserve from 1.25 to 1.4, and extending the term of the plan to April 29, 2030. As of June 30, 2020, there were 4,267,255 shares available for future grant under the Amended and Restated 2019 Plan. Employee Stock Purchase Plan Employees are able to purchase stock under the Vericel Corporation Employee Stock Purchase Plan (ESPP). The ESPP allows for the issuance of an aggregate of 1,000,000 shares of common stock of which 672,907 have been issued since the inception of the benefit in 2015. Participation in this plan is available to substantially all employees. The ESPP is a compensatory plan accounted for under the expense recognition provisions of the share-based payment accounting standards. Compensation expense is recorded based on the fair market value of the purchase options at the grant date, which corresponds to the first day of each purchase period and is amortized over the purchase period. In July 2020, employees purchased 44,137 shares resulting in proceeds from the sale of common stock of $0.3 million under the ESPP for the second quarter of 2020. Service-Based Stock Options During the three and six months ended June 30, 2020, the Company granted service-based options to purchase common stock of 110,750 and 1,296,890, respectively, and 152,500 and 1,638,510, respectively, for the same periods in 2019. The exercise price of the options is the fair market value per share of common stock on the grant date, generally vest over four years (other than non-employee director options which vest over one year) and have a term of ten years. The Company issues new shares upon the exercise of stock options. The weighted average grant-date fair value of service-based options granted during the three and six months ended June 30, 2020 was $8.82 and $8.66, respectively and $11.94 and $12.74, respectively, for the same periods in 2019. Restricted Stock Units During the three and six months ended June 30, 2020 and 2019, the Company granted 10,700 and 196,836, service-based restricted stock units, respectively and 10,500 and 186,922, respectively, for the same periods in 2019. The restricted stock units vest annually over four years in equal installments commencing on the first anniversary of the grant date (other than non-employee director options which vest over one year from the grant date). The Company issues new shares upon the vesting of restricted stock units. Restricted stock awards are recorded at fair value at the date of grant, which is based on the closing share price on the grant date. Compensation expense is recorded for restricted stock units that are expected to vest based on their fair value at grant date and is amortized over the expected vesting period. The weighted average grant-date fair value of restricted stock units granted during the three and six months ended June 30, 2020 was $14.49 and $11.41, respectively and $16.62 and $17.71, respectively, for the same periods in 2019. The aggregate fair value of restricted stock units granted in the three and six months ended June 30, 2020 was $0.2 million and $2.2 million, respectively and $0.2 million and $3.3 million, respectively, for the same periods in 2019. As a result of 36,212 units vesting during the three months ended March 31, 2020, 13,872 shares were withheld for payment of taxes on the employee's behalf and retired from the 2019 Plan. During the three months ended June 30, 2020, 10,500 units vested and no shares were withheld for payment of taxes, as no shares are withheld at vesting for shares awarded to the Company's Board of Directors. Stock Compensation Expense Non-cash stock-based compensation expense (employee stock purchase plan, service-based stock options and restricted stock units) included in cost of goods sold, research and development expenses and selling, general and administrative expenses is summarized in the following table: Three Months Ended June 30, Six Months Ended June 30, (in thousands) 2020 2019 2020 2019 Cost of goods sold $ 568 $ 716 $ 997 $ 976 Research and development 484 886 $ 1,060 1,410 Selling, general and administrative 3,325 2,581 $ 6,087 4,424 Total non-cash stock-based compensation expense $ 4,377 $ 4,183 $ 8,144 $ 6,810

Cash Equivalents and Investment

Cash Equivalents and Investments	6 Months Ended
	Jun. 30, 2020
Cash and Cash Equivalents [Abstract]
Cash Equivalents and Investments	Cash Equivalents and Investments Marketable debt securities held by the Company are classified as available-for-sale pursuant to ASC 320, Investments – Debt and Equity Securities , and carried at fair value in the accompanying consolidated balance sheets on a settlement date basis. The following tables summarize the gross unrealized gains and losses of the Company’s marketable securities as of June 30, 2020 and December 31, 2019: June 30, 2020 Gross Unrealized Estimated Fair Value Amortized Cost Gains Losses Credit Losses Money market funds $ 44,985 $ — $ — — $ 44,985 Commercial paper 3,685 — — — 3,685 Corporate notes 8,840 55 — — 8,895 U.S. government securities 7,776 67 — — 7,843 U.S. asset-backed securities 4,640 23 — — 4,663 $ 69,926 $ 145 $ — $ — $ 70,071 Classified as: Cash equivalents $ 44,985 Short term investments 25,086 $ 70,071 December 31, 2019 Gross Unrealized Estimated Fair Value (In thousands) Amortized Cost Gains Losses Money market funds $ 5,381 $ — $ — $ 5,381 Commercial paper 11,892 — — 11,892 Corporate notes 18,369 11 — 18,380 U.S. government securities 11,291 4 — 11,295 U.S. asset-backed securities 10,503 6 — 10,509 $ 57,436 $ 21 $ — $ 57,457 Classified as: Cash equivalents $ 5,381 Short-term investments 42,829 Long term investments 9,247 $ 57,457 As of June 30, 2020 and December 31, 2019 , we held both short-term and long-term investments. Investments classified as short-term have maturities of less than one year. Investments classified as long-term are those that: (i) have a maturity of greater than one year, and (ii) we do not intend to liquidate within the next twelve months, although these funds are available for use and, therefore, are classified as available-for-sale . The Company's investment strategy is to buy short-duration marketable securities with a high credit rating. As of June 30, 2020, all marketable securities held by the Company had remaining contractual maturities of three years or less. U nrealized gains are included as a component of accumulated other comprehensive income in the condensed consolidated balance sheets and statements of stockholders’ equity and a component of total comprehensive loss in the condensed consolidated statements of comprehensive loss, until realized. Unrealized losses are evaluated for impairment under ASC 326, Financial Instruments - Credit Losses , to determine if the impairment is credit-related or non credit-related. Credit-related impairment is recognized as an allowance on the balance sheet with a corresponding adjustment to earnings, and non credit-related impairment is recognized in other comprehensive income, net of taxes. There were no material realized losses on marketable securities for the three and six months ended June 30, 2020 and 2019. The Company evaluated its investments for impairment under ASC 326. Any allowance for credit losses are recorded at the lower of either the fair market value less book value or the difference between the present value of future cash flows and the book value. As of June 30, 2020, the analysis under ASU 2016-13 and the current macroeconomic impact of the COVID-19 pandemic did not result in material allowances for credit losses.

Fair Value Measurements

Fair Value Measurements	6 Months Ended
	Jun. 30, 2020
Fair Value Disclosures [Abstract]
Fair Value Measurements	Fair Value Measurements The Company’s fair value measurements are classified and disclosed in one of the following three categories: • Level 1: Unadjusted quoted prices in active markets that are accessible at the measurement date for identical, unrestricted assets or liabilities; • Level 2: Quoted prices in markets that are not active, or inputs which are observable, either directly or indirectly, for substantially the full term of the asset or liability; • Level 3: Prices or valuation techniques that require inputs that are both significant to the fair value measurement and unobservable (i.e., supported by little or no market activity). There was no movement between Level 1 and Level 2 or between Level 2 and Level 3 from December 31, 2019 to June 30, 2020. Assets and liabilities measured at fair value are classified in their entirety based on the lowest level of input that is significant to the fair value measurement. The commercial paper, corporate notes, U.S. government securities and asset-backed securities are classified as Level 2 as they were valued based upon quoted market prices for similar instruments in active markets, quoted prices for identical or similar instruments in markets that are not active and model-based valuation techniques for which all significant inputs are observable in the market or can be corroborated by observable market data for substantially the full term of the assets. The following table summarizes the valuation of the Company’s financial instruments that are measured at fair value on a recurring basis: June 30, 2020 December 31, 2019 Fair value measurement category Fair value measurement category (In thousands) Total Level 1 Level 2 Level 3 Total Level 1 Level 2 Level 3 Assets: Money market funds $ 44,985 $ 44,985 $ — $ — $ 5,381 $ 5,381 $ — $ — Commercial paper 3,685 — 3,685 — 11,892 — 11,892 — Corporate notes 8,895 — 8,895 — 18,380 — 18,380 — U.S. government securities 7,843 — 7,843 — 11,295 — 11,295 — U.S. asset-backed securities 4,663 — 4,663 — 10,509 — 10,509 — $ 70,071 $ 44,985 $ 25,086 $ — $ 57,457 $ 5,381 $ 52,076 $ — The fair values of the cash equivalents and marketable securities are based on observable market prices. See note 8 for impact of ASU 2016-13 on the investment valuation.

Net Loss Per Common Share

Net Loss Per Common Share	6 Months Ended
	Jun. 30, 2020
Earnings Per Share [Abstract]
Net Loss Per Common Share	Net Loss Per Common Share The following reflects the net loss attributable to common shareholders and share data used in the basic and diluted earnings per share computations using the two class method: Three Months Ended June 30, Six Months Ended June 30, (Amounts in thousands, except per share amounts) 2020 2019 2020 2019 Numerator: Net loss $ (8,269) $ (19,792) $ (12,974) $ (22,636) Denominator: Basic and diluted EPS: weighted-average common shares outstanding 45,137 43,956 45,031 43,841 Net loss per share attributable to common shareholders (basic and diluted) $ (0.18) $ (0.45) $ (0.29) $ (0.52) Anti-dilutive shares excluded from the calculation of diluted earnings per share (a) (amounts in millions): Stock options 6.0 5.6 6.0 5.6 Restricted stock unit awards 0.3 0.2 0.3 0.2 Warrants — 0.1 — 0.1 (a) Common equivalent shares are not included in the diluted per share calculation where the effect of their inclusion would be anti-dilutive.

Nexobrid License and Supply Agr

Nexobrid License and Supply Agreements	6 Months Ended
	Jun. 30, 2020
Related Party Transactions [Abstract]
Nexobrid License and Supply Agreements	NexoBrid License and Supply Agreements On May 6, 2019, the Company entered into exclusive license and supply agreements with MediWound Ltd. (MediWound) to commercialize NexoBrid ® and any improvements to NexoBrid in all countries of North America. NexoBrid is a topically-administered biological product that enzymatically removes nonviable burn tissue, or eschar, in patients with deep partial and full-thickness thermal burns. NexoBrid is currently in clinical development in North America, and pursuant to the terms of the license agreement, MediWound will continue to conduct all clinical activities described in the development plan to support the BLA filing with the United States Food and Drug Administration (FDA) under the supervision of a Central Steering Committee comprised of members of each party. On June 30, 2020, the Company announced the submission of the BLA to the FDA seeking the approval of NexoBrid. NexoBrid is approved in the European Union and other international markets and has been designated as an orphan biologic in the United States, European Union and other international markets. In May 2019, the Company paid MediWound $17.5 million in consideration of the license. The $17.5 million upfront payment was recorded to research and development expense during 2019, as the license was considered in process research and development. The Company is also obligated to pay MediWound $7.5 million upon U.S. regulatory approval of the BLA for NexoBrid and up to $125 million contingent upon meeting certain sales milestones. The first sales milestone of $7.5 million would be triggered when annual net sales of NexoBrid or improvements to it in North America exceed $75 million. The Company also will pay MediWound tiered royalties on net sales ranging from mid-high single-digit to mid-teen percentages, subject to customary reductions. The U.S. Biomedical Advanced Research and Development Authority (BARDA) has committed to procure NexoBrid, and the Company will pay a percentage of gross profits to MediWound on initial committed amounts and a royalty on any additional BARDA purchases of NexoBrid beyond the initial committed amount. The Company also entered into a supply agreement with MediWound under which MediWound will manufacture NexoBrid for the Company on a unit price basis which may be increased based on a published index. MediWound is obligated to supply the Company with NexoBrid for sale in North America on an exclusive basis for the first five years of the term of the supply agreement. After the exclusivity period or upon supply failure, the Company will be permitted to establish an alternate source of supply. As of June 30, 2020, the milestone payments are not yet probable and therefore, not considered a liability.

Commitments and Contingencies

Commitments and Contingencies	6 Months Ended
	Jun. 30, 2020
Commitments and Contingencies Disclosure [Abstract]
Commitments and Contingencies	Commitments and Contingencies The Company's purchase commitments consist of minimum purchase amounts of materials used in the Company's cell manufacturing process to manufacture its marketed cell therapy products.

Basis of Presentation - (Polici

Basis of Presentation - (Policies)	6 Months Ended
	Jun. 30, 2020
Accounting Policies [Abstract]
Recent Accounting Pronouncements	Recent Accounting Pronouncements Measuring Credit Losses on Financial Instruments The FASB issued updated guidance on measuring credit losses on financial instruments. The guidance removes the thresholds that companies apply to measure credit losses on financial instruments measured at amortized cost, such as loans, receivables, and held-to-maturity debt securities. Prior to the updated guidance, credit losses are recognized when it is probable that the loss has been incurred. The revised guidance removes all recognition thresholds and requires companies to recognize an allowance for credit losses for the difference between the amortized cost basis of a financial instrument and the amount of amortized cost that a company expected to collect over the instrument’s contractual life. The Accounting Standard Update (ASU) 2016-13, Financial Instruments-Credit Losses (Topic 326), became effective for the Company January 1, 2020. See note 4 and note 8 for further discussion. Fair Value Measurement Disclosure The FASB issued updated guidance through ASU 2018-13, Fair Value Measurement (Topic 820) Disclosure Framework-Changes to the Disclosure Requirements for Fair Value Measurement. The revised guidance is intended to develop a more consistent disclosure framework that will increase clarity, remove, modify and add certain fair value disclosures to improve the effectiveness of the Company’s disclosures in the notes of the financial statements. This guidance became effective for the Company January 1, 2020 and had no impact to its condensed consolidated financial statements. Simplifying the Accounting for Income Taxes In December 2019, the FASB issued ASU 2019-12, Simplifying the Accounting for Income Taxes (ASC 740). The ASU enhances and simplifies various aspects of the income tax accounting guidance in ASC 740, including requirements related to hybrid tax regimes, the tax basis step-up in goodwill obtained in a transaction that is not a business combination, separate financial statements of entities not subject to tax, the intra-period tax allocation exception to the incremental approach, ownership changes in investments, changes from a subsidiary to an equity method investment, interim-period accounting for enacted changes in tax law, and the year-to-date loss limitation in interim-period tax accounting. This guidance is effective for the Company for annual and interim periods beginning after December 31, 2020; however, early adoption is permitted. The Company is currently in the process of evaluating the impact to its condensed consolidated financial statements.

Basis of Presentation (Tables)

Basis of Presentation (Tables)	6 Months Ended
	Jun. 30, 2020
Accounting Policies [Abstract]
Supplementary cash flows information	The following table presents certain supplementary cash flows information for the six months ended June 30, 2020 and 2019: Six Months Ended June 30, (In thousands) 2020 2019 Supplementary Cash Flows information: Non-cash information: Right-of-use asset and lease liability recognized $ 429 $ 560 Additions to property, plant and equipment included in accounts payable 55 365 Cash information: Interest paid (net of interest capitalized) $ 3 $ 4

Revenue (Tables)

Revenue (Tables)	6 Months Ended
	Jun. 30, 2020
Risks and Uncertainties [Abstract]
Disaggregation of Revenue	The following table and description below shows the products from which the Company generated its revenue: Three Months Ended June 30, Six Months Ended June 30, Revenue by product (in thousands) 2020 2019 2020 2019 MACI implants and kits Implants based on contracted rate sold through a specialty pharmacy (a) $ 9,790 $ 12,989 $ 21,218 $ 22,776 Implants subject to third party reimbursement sold through a specialty pharmacy (b) 2,819 3,459 6,335 6,202 Implants sold direct based on contracted rates (c) 1,806 3,450 4,916 6,676 Implants sold direct subject to third party reimbursement (d) 589 281 1,016 603 Biopsy kits - direct bill 348 557 811 1,099 Change in estimates related to prior periods (e) (248) 87 1,095 50 Epicel Direct bill (hospital) 4,910 5,328 11,301 10,555 Total revenue $ 20,014 $ 26,151 $ 46,692 $ 47,961 (a) Represents implants sold through Orsini and AllCare in both 2020 and 2019 in which such specialty pharmacies have entered into a direct contract with the underlying insurance provider. The amount of reimbursement is based on contracted rates at the time of sale supported by the pharmacy's direct contracts. Also represents direct sales under a contract to the specialty distributor DMS. (b) Represents implants sold through Orsini or AllCare in which such specialty pharmacy does not have a direct contract with the underlying payer. The amount of reimbursement is established based on a payer or state fee schedule and/or payer history. (c) Represents implants sold directly from the Company to the facility based on a contract and known price agreed upon prior to the surgery date. (d) Represents implants sold directly from the Company to the facility based on a contract and known price agreed upon prior to the surgery date. The payment terms are subject to third-party reimbursement from an underlying insurance provider. (e) Primarily represents changes in estimates related to implants sold through Orsini or AllCare in which such specialty pharmacy does not have a direct contract with the underlying payer. The initial estimate of the amount of reimbursement is established based on a payer or state fee schedule and/or payer history. The change in estimates is a result of additional information or actual cash collections received in the current period.
Schedules of concentration of risk	The table below shows the Company’s total Epicel revenue and accounts receivable balances from customers whose revenue or accounts receivable concentration is greater than 10% in any of the periods disclosed below. The Company did not have MACI revenue or accounts receivable concentrations greater than 10% in any of the periods disclosed below. Revenue Concentration Accounts Receivable Concentration Three Months Ended June 30, Six Months Ended June 30, June 30, December 31, 2020 2019 2020 2019 2020 2019 Epicel 6 % 6 % 10 % 8 % 3 % 2 %

Selected Balance Sheet Compon_2

Selected Balance Sheet Components (Tables)	6 Months Ended
	Jun. 30, 2020
Balance Sheet Related Disclosures [Abstract]
Schedule of inventory	Inventory as of June 30, 2020 and December 31, 2019: (In thousands) June 30, 2020 December 31, 2019 Raw materials $ 7,853 $ 6,085 Work-in-process 513 541 Finished goods 51 190 Inventory $ 8,417 $ 6,816
Schedule of property and equipment, net	Property and Equipment, net as of June 30, 2020 and December 31, 2019: (In thousands) June 30, 2020 December 31, 2019 Machinery and equipment $ 3,279 $ 3,152 Furniture, fixtures and office equipment 810 775 Computer equipment and software 6,393 6,174 Leasehold improvements 5,256 5,256 Construction in process 1,311 859 Financing right-of-use lease 129 148 Total property and equipment, gross 17,178 16,364 Less accumulated depreciation (10,138) (9,220) $ 7,040 $ 7,144
Schedule of accrued expenses	Accrued Expenses as of June 30, 2020 and December 31, 2019 are as follows: (In thousands) June 30, 2020 December 31, 2019 Bonus related compensation $ 2,872 $ 5,116 Employee related accruals 2,578 1,785 Other accrued expenses 2,525 1,047 Accrued expenses $ 7,975 $ 7,948

Leases (Tables)

Leases (Tables)	6 Months Ended
	Jun. 30, 2020
Leases [Abstract]
Assets And Liabilities	Total leased assets and liabilities as reassessed under the updated guidance and classified on the balance sheet, as of June 30, 2020 and December 31, 2019 are as follows: (In thousands) Classification June 30, 2020 December 31, 2019 Assets Operating Right-of-use assets $ 23,800 $ 25,103 Finance Property and equipment, net 129 148 $ 23,929 $ 25,251 Liabilities Current Operating Current portion of operating lease liabilities $ 5,570 $ 5,461 Finance Other liabilities 41 41 $ 5,611 $ 5,502 Non-current Operating Operating lease liabilities $ 20,881 $ 22,242 Finance Other long-term liabilities 93 110 $ 20,974 $ 22,352

Stock-Based Compensation (Table

Stock-Based Compensation (Tables)	6 Months Ended
	Jun. 30, 2020
Share-based Payment Arrangement [Abstract]
Schedule of non-cash stock-based compensation expense	Non-cash stock-based compensation expense (employee stock purchase plan, service-based stock options and restricted stock units) included in cost of goods sold, research and development expenses and selling, general and administrative expenses is summarized in the following table: Three Months Ended June 30, Six Months Ended June 30, (in thousands) 2020 2019 2020 2019 Cost of goods sold $ 568 $ 716 $ 997 $ 976 Research and development 484 886 $ 1,060 1,410 Selling, general and administrative 3,325 2,581 $ 6,087 4,424 Total non-cash stock-based compensation expense $ 4,377 $ 4,183 $ 8,144 $ 6,810

Cash Equivalents and Investme_2

Cash Equivalents and Investments (Tables)	6 Months Ended
	Jun. 30, 2020
Cash and Cash Equivalents [Abstract]
Schedule of fair value of securities, not including cash	he following tables summarize the gross unrealized gains and losses of the Company’s marketable securities as of June 30, 2020 and December 31, 2019: June 30, 2020 Gross Unrealized Estimated Fair Value Amortized Cost Gains Losses Credit Losses Money market funds $ 44,985 $ — $ — — $ 44,985 Commercial paper 3,685 — — — 3,685 Corporate notes 8,840 55 — — 8,895 U.S. government securities 7,776 67 — — 7,843 U.S. asset-backed securities 4,640 23 — — 4,663 $ 69,926 $ 145 $ — $ — $ 70,071 Classified as: Cash equivalents $ 44,985 Short term investments 25,086 $ 70,071 December 31, 2019 Gross Unrealized Estimated Fair Value (In thousands) Amortized Cost Gains Losses Money market funds $ 5,381 $ — $ — $ 5,381 Commercial paper 11,892 — — 11,892 Corporate notes 18,369 11 — 18,380 U.S. government securities 11,291 4 — 11,295 U.S. asset-backed securities 10,503 6 — 10,509 $ 57,436 $ 21 $ — $ 57,457 Classified as: Cash equivalents $ 5,381 Short-term investments 42,829 Long term investments 9,247 $ 57,457

Fair Value Measurements (Tables

Fair Value Measurements (Tables)	6 Months Ended
	Jun. 30, 2020
Fair Value Disclosures [Abstract]
Summary of valuation of the Company's investments and financial instruments that are measured at fair value on a recurring basis	The following table summarizes the valuation of the Company’s financial instruments that are measured at fair value on a recurring basis: June 30, 2020 December 31, 2019 Fair value measurement category Fair value measurement category (In thousands) Total Level 1 Level 2 Level 3 Total Level 1 Level 2 Level 3 Assets: Money market funds $ 44,985 $ 44,985 $ — $ — $ 5,381 $ 5,381 $ — $ — Commercial paper 3,685 — 3,685 — 11,892 — 11,892 — Corporate notes 8,895 — 8,895 — 18,380 — 18,380 — U.S. government securities 7,843 — 7,843 — 11,295 — 11,295 — U.S. asset-backed securities 4,663 — 4,663 — 10,509 — 10,509 — $ 70,071 $ 44,985 $ 25,086 $ — $ 57,457 $ 5,381 $ 52,076 $ —

Net Loss Per Common Share (Tabl

Net Loss Per Common Share (Tables)	6 Months Ended
	Jun. 30, 2020
Earnings Per Share [Abstract]
Schedule of net loss attributable to common shareholders and share data used in the basic and diluted earnings per share computations using the two class method	The following reflects the net loss attributable to common shareholders and share data used in the basic and diluted earnings per share computations using the two class method: Three Months Ended June 30, Six Months Ended June 30, (Amounts in thousands, except per share amounts) 2020 2019 2020 2019 Numerator: Net loss $ (8,269) $ (19,792) $ (12,974) $ (22,636) Denominator: Basic and diluted EPS: weighted-average common shares outstanding 45,137 43,956 45,031 43,841 Net loss per share attributable to common shareholders (basic and diluted) $ (0.18) $ (0.45) $ (0.29) $ (0.52) Anti-dilutive shares excluded from the calculation of diluted earnings per share (a) (amounts in millions): Stock options 6.0 5.6 6.0 5.6 Restricted stock unit awards 0.3 0.2 0.3 0.2 Warrants — 0.1 — 0.1 (a) Common equivalent shares are not included in the diluted per share calculation where the effect of their inclusion would be anti-dilutive.

Organization - Narrative (Detai

Organization - Narrative (Details) $ in Thousands	3 Months Ended				6 Months Ended
	Jun. 30, 2020USD ($)product	Mar. 31, 2020USD ($)	Jun. 30, 2019USD ($)	Mar. 31, 2019USD ($)	Jun. 30, 2020USD ($)productsegment	Jun. 30, 2019USD ($)	Dec. 31, 2019USD ($)	Dec. 31, 2018USD ($)
Organization, Consolidation and Presentation of Financial Statements [Abstract]
Number of therapy products | product	2				2
Number of reportable segments | segment					1
Accumulated deficit	$ 391,653				$ 391,653		$ 378,679
Net loss	8,269	$ 4,705	$ 19,792	$ 2,844	12,974	$ 22,636
Cash, cash equivalents, and restricted cash	55,793		$ 13,962		55,793	$ 13,962	$ 26,978	$ 18,286
Short term investments	$ 25,100				$ 25,100

Basis of Presentation - Supplem

Basis of Presentation - Supplementary cash flows information (Details) - USD ($) $ in Thousands	6 Months Ended
	Jun. 30, 2020	Jun. 30, 2019
Non-cash information:
Right-of-use asset and lease liability recognized	$ 429	$ 560
Additions to property, plant and equipment included in accounts payable	55	365
Interest paid (net of interest capitalized)	$ 3	$ 4

Basis of Presentation - Narrati

Basis of Presentation - Narrative (Details) - USD ($)	Jun. 30, 2020	Dec. 31, 2019	Jun. 30, 2019	Dec. 31, 2018
Accounting Policies [Abstract]
Cash, cash equivalents, and restricted cash	$ 55,793,000	$ 26,978,000	$ 13,962,000	$ 18,286,000
Cash and cash equivalents	55,704,000	$ 26,889,000	14,000,000
Restricted cash	$ 100,000		$ 0

Revenue - (Details)

Revenue - (Details) $ in Thousands	3 Months Ended		6 Months Ended
	Jun. 30, 2020USD ($)pharmacy	Jun. 30, 2019USD ($)	Jun. 30, 2020USD ($)pharmacy	Jun. 30, 2019USD ($)	Dec. 31, 2019USD ($)
CONCENTRATION
Number of specialty pharmacies | pharmacy	2		2
Allowance for doubtful accounts	$ 4,400		$ 4,400		$ 3,900
Change in estimate of uncollectible (percent)			0.50%
Change in revenue recognized due to 0.5% change in uncollectible percentage			$ 100
Increase (decrease) to revenues	20,014	$ 26,151	46,692	$ 47,961
Accounting Standards Update 2014-09 | Difference between Revenue Guidance in Effect before and after Topic 606
CONCENTRATION
Increase (decrease) to revenues	(248)	$ 87	1,095	$ 50
COVID-19 potential impacts
CONCENTRATION
Allowance for doubtful accounts	$ 100		$ 100

Revenue - Disaggregation of Rev

Revenue - Disaggregation of Revenue (Details) - USD ($) $ in Thousands	3 Months Ended		6 Months Ended
	Jun. 30, 2020	Jun. 30, 2019	Jun. 30, 2020	Jun. 30, 2019
Disaggregation of Revenue [Line Items]
Product sales, net	$ 20,014	$ 26,151	$ 46,692	$ 47,961
Revenues	20,014	26,151	46,692	47,961
Accounting Standards Update 2014-09 | Difference between Revenue Guidance in Effect before and after Topic 606
Disaggregation of Revenue [Line Items]
Product sales, net	(248)	87	1,095	50
Through Intermediary | Implants | Contract rate
Disaggregation of Revenue [Line Items]
Product sales, net	9,790	12,989	21,218	22,776
Through Intermediary | Implants | Time-and-materials contract
Disaggregation of Revenue [Line Items]
Product sales, net	2,819	3,459	6,335	6,202
Time-and-materials contract | Implants | Time-and-materials contract
Disaggregation of Revenue [Line Items]
Product sales, net	589	281	1,016	603
Provider or Facility | Implants | Contract rate
Disaggregation of Revenue [Line Items]
Product sales, net	1,806	3,450	4,916	6,676
Directly to consumer | Biopsy kits
Disaggregation of Revenue [Line Items]
Product sales, net	348	557	811	1,099
Directly to consumer | Epicel
Disaggregation of Revenue [Line Items]
Product sales, net	$ 4,910	$ 5,328	$ 11,301	$ 10,555

Revenue - Schedules of concentr

Revenue - Schedules of concentration of risk (Details) - Customer concentration - Epicel	3 Months Ended		6 Months Ended		12 Months Ended
	Jun. 30, 2020	Jun. 30, 2019	Jun. 30, 2020	Jun. 30, 2019	Dec. 31, 2019
Revenue Concentration
Product Information [Line Items]
Concentration risk (as a percent)	6.00%	6.00%	10.00%	8.00%
Accounts Receivable Concentration
Product Information [Line Items]
Concentration risk (as a percent)			3.00%		2.00%

Selected Balance Sheet Compon_3

Selected Balance Sheet Components - Schedule of inventory (Details) - USD ($) $ in Thousands	Jun. 30, 2020	Dec. 31, 2019
Inventory:
Raw materials	$ 7,853	$ 6,085
Work-in-process	513	541
Finished goods	51	190
Inventory	$ 8,417	$ 6,816

Selected Balance Sheet Compon_4

Selected Balance Sheet Components - Schedule of property and equipment, net (Details) - USD ($) $ in Thousands	3 Months Ended		6 Months Ended
	Jun. 30, 2020	Jun. 30, 2019	Jun. 30, 2020	Jun. 30, 2019	Dec. 31, 2019
Property and equipment, net:
Financing right-of-use lease	$ 129		$ 129		$ 148
Total property and equipment, gross	17,178		17,178		16,364
Less accumulated depreciation	(10,138)		(10,138)		(9,220)
Property and equipment, net	7,040		7,040		7,144
Depreciation expense	500	$ 400	1,100	$ 700
Machinery and equipment
Property and equipment, net:
Total property and equipment, gross	3,279		3,279		3,152
Furniture, fixtures and office equipment
Property and equipment, net:
Total property and equipment, gross	810		810		775
Computer equipment and software
Property and equipment, net:
Total property and equipment, gross	6,393		6,393		6,174
Leasehold improvements
Property and equipment, net:
Total property and equipment, gross	5,256		5,256		5,256
Construction in process
Property and equipment, net:
Total property and equipment, gross	$ 1,311		$ 1,311		$ 859

Selected Balance Sheet Compon_5

Selected Balance Sheet Components - Schedule of accrued expenses (Details) - USD ($) $ in Thousands	Jun. 30, 2020	Dec. 31, 2019
Accrued expenses
Bonus related compensation	$ 2,872	$ 5,116
Employee related accruals	2,578	1,785
Other accrued expenses	2,525	1,047
Accrued expenses	$ 7,975	$ 7,948

Leases - Narrative (Details)

Leases - Narrative (Details) - USD ($) $ in Millions	3 Months Ended		6 Months Ended
	Jun. 30, 2020	Jun. 30, 2019	Jun. 30, 2020	Jun. 30, 2019
Leases [Abstract]
Short-term lease costs (less than)	$ 0.1	$ 0.1	$ 0.1	$ 0.1
Operating lease expense	1.4	1.3	2.9	2.6
Finance lease expense	$ 0.1	$ 0.1	$ 0.1	$ 0.1

Leases - Assets And Liabilities

Leases - Assets And Liabilities (Details) - USD ($) $ in Thousands	Jun. 30, 2020	Dec. 31, 2019
Assets
Operating	$ 23,800	$ 25,103
Finance	129	148
Right-of-use assets	23,929	25,251
Current
Operating	5,570	5,461
Finance	41	41
Lease liability current	5,611	5,502
Non-current
Operating	20,881	22,242
Finance	93	110
Lease liability noncurrent	$ 20,974	$ 22,352
Finance Lease, Right-of-Use Asset, Statement of Financial Position [Extensible List]	us-gaap:PropertyPlantAndEquipmentAndFinanceLeaseRightOfUseAssetAfterAccumulatedDepreciationAndAmortization
Finance Lease, Liability, Statement of Financial Position [Extensible List]	us-gaap:OtherLiabilities
Finance Lease, Liability, Current, Statement of Financial Position [Extensible List]	us-gaap:OtherLiabilitiesCurrent
Finance Lease, Liability, Noncurrent, Statement of Financial Position [Extensible List]	us-gaap:OtherLiabilitiesNoncurrent

Stock-Based Compensation - Narr

Stock-Based Compensation - Narrative (Details) $ / shares in Units, $ in Thousands	1 Months Ended	3 Months Ended				6 Months Ended		66 Months Ended
	Jul. 31, 2020USD ($)shares	Jun. 30, 2020USD ($)$ / sharesshares	Mar. 31, 2020USD ($)shares	Jun. 30, 2019USD ($)$ / sharesshares	Mar. 31, 2019USD ($)shares	Jun. 30, 2020USD ($)$ / sharesshares	Jun. 30, 2019USD ($)$ / sharesshares	Jun. 30, 2020shares	Apr. 29, 2020shares	Apr. 28, 2020
Stock-Based Compensation
Shares issued under the Employee Stock Purchase Plan (in shares) | $		$ 257	$ 224	$ 211	$ 218
Employee stock
Stock-Based Compensation
Common stock available for issuance (in shares)		1,000,000				1,000,000		1,000,000
Common stock granted since inception (in shares)								672,907
Employee stock | Subsequent event
Stock-Based Compensation
Shares purchased during period (in shares)	44,137
Shares issued under the Employee Stock Purchase Plan (in shares) | $	$ 300
Service-based stock options
Stock-Based Compensation
Expiration period						10 years
Vesting period						4 years
Granted (in shares)		110,750		152,500		1,296,890	1,638,510
Weighted average grant-date fair value (in dollars per share) | $ / shares		$ 8.82		$ 11.94		$ 8.66	$ 12.74
Service-based stock options | Nonemployee directors
Stock-Based Compensation
Expiration period						10 years
Vesting period						1 year
Restricted Stock Units (RSUs)
Stock-Based Compensation
Vesting period						4 years
Restricted stock units granted (shares)		10,700		10,500		196,836	186,922
Weighted-average grant date fair value (in usd per share) | $ / shares		$ 14.49		$ 16.62		$ 11.41	$ 17.71
Grant-date fair value of restricted stock units granted | $		$ 200		$ 200		$ 2,200	$ 3,300
Shares vested in period (shares)		10,500	36,212
Restricted stock withheld for employee tax remittance (in shares)		0	13,872
Restricted Stock Units (RSUs) | Nonemployee directors
Stock-Based Compensation
Vesting period						1 year
Common Stock
Stock-Based Compensation
Shares purchased during period (in shares)		32,000	20,000	14,000	19,000
Shares issued under the Employee Stock Purchase Plan (in shares) | $		$ 257	$ 224	$ 211	$ 218
Restricted stock withheld for employee tax remittance (in shares)			14,000
Prior Plans
Stock-Based Compensation
Awards available for future grant under the Plan (in shares)		0				0		0
Omnibus Incentive Plan 2019
Stock-Based Compensation
Awards available for future grant under the Plan (in shares)		4,267,255				4,267,255		4,267,255
Ratio of full value awards against share reserve									1.4	1.25
Omnibus Incentive Plan 2019 | Common Stock
Stock-Based Compensation
Increase in number of shares available for issuance (shares)									2,400,000

Stock-Based Compensation - Sche

Stock-Based Compensation - Schedule of non-cash stock-based compensation expense (Details) - Employee stock purchase plan and service-based stock options - USD ($) $ in Thousands	3 Months Ended		6 Months Ended
	Jun. 30, 2020	Jun. 30, 2019	Jun. 30, 2020	Jun. 30, 2019
Share-based Payment Arrangement, Expensed and Capitalized, Amount [Line Items]
Total non-cash stock-based compensation expense	$ 4,377	$ 4,183	$ 8,144	$ 6,810
Cost of goods sold
Share-based Payment Arrangement, Expensed and Capitalized, Amount [Line Items]
Total non-cash stock-based compensation expense	568	716	997	976
Research and development
Share-based Payment Arrangement, Expensed and Capitalized, Amount [Line Items]
Total non-cash stock-based compensation expense	484	886	1,060	1,410
Selling, general and administrative
Share-based Payment Arrangement, Expensed and Capitalized, Amount [Line Items]
Total non-cash stock-based compensation expense	$ 3,325	$ 2,581	$ 6,087	$ 4,424

Cash Equivalents and Investme_3

Cash Equivalents and Investments (Details) - USD ($) $ in Thousands	Jun. 30, 2020	Dec. 31, 2019
Marketable Securities [Line Items]
Amortized Cost	$ 69,926	$ 57,436
Gains	145	21
Losses	0	0
Credit Losses	0
Estimated Fair Value	70,071	57,457
Cash equivalents
Marketable Securities [Line Items]
Estimated Fair Value	44,985	5,381
Short term investments
Marketable Securities [Line Items]
Estimated Fair Value	25,086	42,829
Long term investments
Marketable Securities [Line Items]
Estimated Fair Value		9,247
Money market funds
Marketable Securities [Line Items]
Amortized Cost	44,985	5,381
Gains	0	0
Losses	0	0
Credit Losses	0
Estimated Fair Value	44,985	5,381
Commercial paper
Marketable Securities [Line Items]
Amortized Cost	3,685	11,892
Gains	0	0
Losses	0	0
Credit Losses	0
Estimated Fair Value	3,685	11,892
Corporate notes
Marketable Securities [Line Items]
Amortized Cost	8,840	18,369
Gains	55	11
Losses	0	0
Credit Losses	0
Estimated Fair Value	8,895	18,380
U.S. government securities
Marketable Securities [Line Items]
Amortized Cost	7,776	11,291
Gains	67	4
Losses	0	0
Credit Losses	0
Estimated Fair Value	7,843	11,295
U.S. asset-backed securities
Marketable Securities [Line Items]
Amortized Cost	4,640	10,503
Gains	23	6
Losses	0	0
Credit Losses	0
Estimated Fair Value	$ 4,663	$ 10,509

Fair Value Measurements (Detail

Fair Value Measurements (Details) - USD ($) $ in Thousands	Jun. 30, 2020	Dec. 31, 2019
Liabilities that are measured at fair value on a recurring basis
Debt securities, fair value	$ 70,071	$ 57,457
Recurring
Liabilities that are measured at fair value on a recurring basis
Assets, fair value	70,071	57,457
Recurring | Level 1
Liabilities that are measured at fair value on a recurring basis
Assets, fair value	44,985	5,381
Recurring | Level 2
Liabilities that are measured at fair value on a recurring basis
Assets, fair value	25,086	52,076
Recurring | Level 3
Liabilities that are measured at fair value on a recurring basis
Assets, fair value	0	0
Commercial paper | Recurring
Liabilities that are measured at fair value on a recurring basis
Debt securities, fair value	3,685	11,892
Commercial paper | Recurring | Level 1
Liabilities that are measured at fair value on a recurring basis
Debt securities, fair value	0	0
Commercial paper | Recurring | Level 2
Liabilities that are measured at fair value on a recurring basis
Debt securities, fair value	3,685	11,892
Commercial paper | Recurring | Level 3
Liabilities that are measured at fair value on a recurring basis
Debt securities, fair value	0	0
Corporate Note Securities | Recurring
Liabilities that are measured at fair value on a recurring basis
Debt securities, fair value	8,895	18,380
Corporate Note Securities | Recurring | Level 1
Liabilities that are measured at fair value on a recurring basis
Debt securities, fair value	0	0
Corporate Note Securities | Recurring | Level 2
Liabilities that are measured at fair value on a recurring basis
Debt securities, fair value	8,895	18,380
Corporate Note Securities | Recurring | Level 3
Liabilities that are measured at fair value on a recurring basis
Debt securities, fair value	0	0
US Government Debt Securities | Recurring
Liabilities that are measured at fair value on a recurring basis
Debt securities, fair value	7,843	11,295
US Government Debt Securities | Recurring | Level 1
Liabilities that are measured at fair value on a recurring basis
Debt securities, fair value	0	0
US Government Debt Securities | Recurring | Level 2
Liabilities that are measured at fair value on a recurring basis
Debt securities, fair value	7,843	11,295
US Government Debt Securities | Recurring | Level 3
Liabilities that are measured at fair value on a recurring basis
Debt securities, fair value	0	0
Asset-backed Securities
Liabilities that are measured at fair value on a recurring basis
Debt securities, fair value	4,663	10,509
Asset-backed Securities | Recurring
Liabilities that are measured at fair value on a recurring basis
Debt securities, fair value	4,663	10,509
Asset-backed Securities | Recurring | Level 1
Liabilities that are measured at fair value on a recurring basis
Debt securities, fair value	0	0
Asset-backed Securities | Recurring | Level 2
Liabilities that are measured at fair value on a recurring basis
Debt securities, fair value	4,663	10,509
Asset-backed Securities | Recurring | Level 3
Liabilities that are measured at fair value on a recurring basis
Debt securities, fair value	0	0
Money market funds | Recurring
Liabilities that are measured at fair value on a recurring basis
Money market funds	44,985	5,381
Money market funds | Recurring | Level 1
Liabilities that are measured at fair value on a recurring basis
Money market funds	44,985	5,381
Money market funds | Recurring | Level 2
Liabilities that are measured at fair value on a recurring basis
Money market funds	0	0
Money market funds | Recurring | Level 3
Liabilities that are measured at fair value on a recurring basis
Money market funds	$ 0	$ 0

Net Loss Per Common Share - Nar

Net Loss Per Common Share - Narrative (Details) - USD ($) $ / shares in Units, shares in Thousands, $ in Thousands	3 Months Ended				6 Months Ended
	Jun. 30, 2020	Mar. 31, 2020	Jun. 30, 2019	Mar. 31, 2019	Jun. 30, 2020	Jun. 30, 2019
Numerator:
Net loss	$ (8,269)	$ (4,705)	$ (19,792)	$ (2,844)	$ (12,974)	$ (22,636)
Denominator for basic and diluted EPS:
Basic and diluted EPS: weighted-average common shares outstanding (in shares)	45,137		43,956		45,031	43,841
Net loss per share attributable to common shareholders (Basic and Diluted) (in dollars per share)	$ (0.18)		$ (0.45)		$ (0.29)	$ (0.52)
Service-based stock options
Denominator for basic and diluted EPS:
Aggregate number of common equivalent shares (related to options, warrants and preferred stock) that have been excluded from computations of diluted net loss per common share (in shares)	6,000		5,600		6,000	5,600
Restricted Stock Units (RSUs)
Denominator for basic and diluted EPS:
Aggregate number of common equivalent shares (related to options, warrants and preferred stock) that have been excluded from computations of diluted net loss per common share (in shares)	300		200		300	200
Warrants
Denominator for basic and diluted EPS:
Aggregate number of common equivalent shares (related to options, warrants and preferred stock) that have been excluded from computations of diluted net loss per common share (in shares)	0		100		0	100

Nexobrid License and Supply A_2

Nexobrid License and Supply Agreements (Details) - MediWound Ltd $ in Millions	1 Months Ended
	May 31, 2019USD ($)
Related Party Transaction [Line Items]
Consideration payment for license	$ 17.5
Payable	17.5
Contingent consideration	7.5
Max contingent consideration	125
Sales Initial milestone	$ 75