Document and Entity Information - USD ($)	12 Months Ended
Document and Entity Information - USD ($)	Dec. 31, 2016	Mar. 10, 2017	Jun. 30, 2016
Document and Entity Information
Entity Registrant Name	Vericel Corp
Entity Central Index Key	0000887359
Current Fiscal Year End Date	--12-31
Entity Filer Category	Accelerated Filer
Document Type	10-K
Document Period End Date	Dec. 31, 2016
Document Fiscal Year Focus	2016
Document Fiscal Period Focus	FY
Amendment Flag	false
Entity Common Stock, Shares Outstanding		32,723,646
Entity Well-known Seasoned Issuer	No
Entity Voluntary Filers	No
Entity Current Reporting Status	Yes
Entity Public Float			$ 54,886,403

CONSOLIDATED BALANCE SHEETS - USD ($) $ in Thousands	Dec. 31, 2016	Dec. 31, 2015
Current assets:
Cash	$ 22,978	$ 14,581
Accounts receivable (net of allowance for doubtful accounts of $225 and $68, respectively)	17,093	10,919
Inventory	3,488	1,379
Other current assets	1,164	464
Total current assets	44,723	27,343
Property and equipment, net	3,875	4,049
Intangible assets	0	2,917
Total assets	48,598	34,309
Current liabilities:
Accounts payable	6,535	7,588
Accrued expenses	4,523	3,603
Warrant liabilities	757	757
Current portion of term loan credit agreement, net of deferred costs of $110	779	0
Other	259	160
Total current liabilities	12,853	12,108
Revolving and term loan credit agreement, net of deferred costs of $293	9,318	0
Long term deferred rent	1,687	0
Other long term debt	32	71
Total liabilities	23,890	12,179
COMMITMENTS AND CONTINGENCIES (Note 17)
Shareholders’ equity:
Common stock, no par value; shares authorized — 75,000; shares issued and outstanding — 31,595 and 23,789, respectively	329,720	307,766
Treasury stock — 0 and 1,250 shares, respectively	0	(3,150)
Warrants	190	0
Accumulated deficit	343,591	324,025
Total shareholders’ equity	24,708	22,130
Total liabilities and shareholders’ equity	48,598	34,309
Series A
Shareholders’ equity:
Preferred stock	0	3,150
Series B-2
Shareholders’ equity:
Preferred stock	$ 38,389	$ 38,389

CONSOLIDATED BALANCE SHEETS (Parenthetical) - USD ($) shares in Thousands, $ in Thousands	Dec. 31, 2016	Dec. 31, 2015
Allowance for doubtful accounts	$ 225	$ 68
Current portion of revolving and term loan credit agreement, deferred costs	110	0
Noncurrent portion of revolving and term loan credit agreement, deferred costs	$ 293	$ 0
Common stock, shares authorized (in shares)	75,000	75,000
Common stock, shares issued (in shares)	31,595	23,789
Common stock, shares outstanding (in shares)	31,595	23,789
Treasury stock, shares reserved (in shares)	0	1,250
Series A
Convertible preferred stock, shares authorized (in shares)	1	1
Convertible preferred stock, shares reserved (in shares)	1	1
Convertible preferred stock, shares issued (in shares)	0	1
Convertible preferred stock, shares outstanding (in shares)	0	1
Series B-2
Convertible preferred stock, shares authorized (in shares)	39	39
Convertible preferred stock, shares reserved (in shares)	39	39
Convertible preferred stock, shares issued (in shares)	12	12
Convertible preferred stock, shares outstanding (in shares)	12	12

CONSOLIDATED STATEMENTS OF OPERATIONS - USD ($) shares in Thousands, $ in Thousands	12 Months Ended
	Dec. 31, 2016	Dec. 31, 2015	Dec. 31, 2014
Income Statement [Abstract]
Product sales, net	$ 54,383	$ 51,168	$ 28,796
Cost of product sales	28,307	26,470	17,293
Gross profit	26,076	24,698	11,503
Research and development	15,295	18,890	21,263
Selling, general and administrative	27,388	22,479	13,774
Loss on impairment of intangible asset	2,638	0	0
Total operating expenses	45,321	41,369	35,037
Loss from operations	(19,245)	(16,671)	(23,534)
Other income (expense):
(Increase) decrease in fair value of warrants	0	324	(27)
Bargain purchase gain	0	0	3,473
Foreign currency translation gain (loss)	(5)	(67)	152
Interest income	8	36	24
Other income (expense)	(10)	47	(2)
Interest expense	(314)	(9)	(6)
Total other income (expense)	(321)	331	3,614
Net loss	$ (19,566)	$ (16,340)	$ (19,920)
Net loss per share attributable to common shareholders (basic and diluted) (in dollars per share)	$ (1.18)	$ (0.97)	$ (2.23)
Weighted average number of common shares outstanding (Basic and Diluted) (in shares)	23,093	23,760	11,642

CONSOLIDATED STATEMENTS OF SHAREHOLDERS' EQUITY - USD ($) shares in Thousands, $ in Thousands	Total	Preferred Stock	Common Stock	Treasury Stock	Accumulated Other Comprehensive Loss	Accumulated Deficit
Beginning balance (in shares) at Dec. 31, 2013		12	4,723	0
Beginning balance at Dec. 31, 2013	$ 3,894	$ 38,389	$ 253,270	$ 0	$ 0	$ (287,765)
Increase (Decrease) in Shareholders' Equity
Net loss	(19,920)					(19,920)
Compensation expense related to stock options granted	839		$ 839
Exercise of stock purchase warrants (in shares)			408
Exercise of stock purchase warrants	2,490		$ 2,490
Issuance of common stock, net of issuance costs (in shares)			18,655
Issuance of common stock, net of issuance costs	48,409		$ 48,409
Foreign currency translation adjustment	(71)				(71)
Ending balance (in shares) at Dec. 31, 2014		12	23,786	0
Ending balance at Dec. 31, 2014	35,641	$ 38,389	$ 305,008	$ 0	(71)	(307,685)
Increase (Decrease) in Shareholders' Equity
Net loss	(16,340)					(16,340)
Preferred stock exchanged for common stock (in shares)		1		(1,250)
Conversion of Series A preferred stock for common stock	0	$ 3,150		$ (3,150)
Compensation expense related to stock options granted	2,747		$ 2,747
Exercised (in shares)			3
Stock option exercises	11		$ 11
Foreign currency translation adjustment	71				71
Ending balance (in shares) at Dec. 31, 2015		13	23,789	(1,250)
Ending balance at Dec. 31, 2015	22,130	$ 41,539	$ 307,766	$ (3,150)	0	(324,025)
Increase (Decrease) in Shareholders' Equity
Net loss	(19,566)					(19,566)
Conversion of Series A preferred stock for common stock (in shares)		(1)		1,250
Conversion of Series A preferred stock for common stock	0	$ (3,150)		$ 3,150
Compensation expense related to stock options granted	2,499		$ 2,499
Issuance of common stock, net of issuance costs (in shares)			7,538
Issuance of common stock, net of issuance costs	18,868		$ 18,868
Exercised (in shares)			39
Stock option exercises	120		$ 120
Shares purchased during period (in shares)			229
Shares issued under the Employee Stock Purchase Plan	467		$ 467
Foreign currency translation adjustment	0
Issuance of warrants	190		$ 190
Ending balance (in shares) at Dec. 31, 2016		12	31,595	0
Ending balance at Dec. 31, 2016	$ 24,708	$ 38,389	$ 329,910	$ 0	$ 0	$ (343,591)

CONSOLIDATED STATEMENTS OF COMPREHENSIVE LOSS - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2016	Dec. 31, 2015	Dec. 31, 2014
Statement of Comprehensive Income [Abstract]
Net loss	$ (19,566)	$ (16,340)	$ (19,920)
Other comprehensive loss
Foreign currency translation	0	71	(71)
Comprehensive loss	$ (19,566)	$ (16,269)	$ (19,991)

CONSOLIDATED STATEMENTS OF CASH FLOWS - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2016	Dec. 31, 2015	Dec. 31, 2014
Operating activities:
Net loss	$ (19,566)	$ (16,340)	$ (19,920)
Adjustments to reconcile net loss to net cash used for operating activities:
Depreciation and amortization	1,886	1,592	752
Loss on impairment of intangible asset	2,638	0	0
Stock compensation expense	2,499	2,747	839
Inventory provision	137	627	0
Change in fair value of warrants	0	(324)	27
Bargain purchase gain	0	0	3,473
Foreign currency translation loss (gain)	5	67	(152)
(Gain) loss on sale of fixed assets	0	(35)	139
Deferred rent expense	670	0	0
Write down of asset retirement obligation	0	(268)	(1,102)
Changes in operating assets and liabilities:
Inventory	(2,245)	(86)	119
Tenant improvement reimbursement	898	0	0
Accounts receivable	(6,174)	(2,728)	(8,139)
Other current assets	(701)	572	(455)
Accounts payable	(1,076)	1,726	2,773
Accrued expenses	920	(764)	3,007
Asset retirement obligation	185	(80)	0
Other non-current assets and liabilities, net	32	(52)	175
Net cash used for operating activities	(19,892)	(13,346)	(25,410)
Investing activities:
Acquisition of CTRM business, net of cash acquired	0	0	(1,450)
Expenditures for property, plant and equipment	(1,415)	(2,427)	(829)
Other	0	35	101
Net cash used for investing activities	(1,415)	(2,392)	(2,178)
Financing activities:
Net proceeds from issuance of common stock and warrants	19,455	11	49,934
Financing costs paid	(213)	0	0
Borrowings under revolving and term loan credit agreements	12,900	0	0
Payments on term loan credit agreement	(2,400)	0	0
Payments on long-term debt	(38)	(35)	(8)
Net cash provided by (used in) financing activities	29,704	(24)	49,926
Effect of exchange rate changes on cash	0	0	(54)
Net increase (decrease) in cash	8,397	(15,762)	22,284
Cash at beginning of period	14,581	30,343	8,059
Cash at end of period	22,978	14,581	30,343
Supplemental cash flow information (non-cash):
Acquisition of business through promissory note	0	0	2,500
Shares exchanged between common and preferred stock	(3,150)	3,150	0
Warrants exchanged for common stock	0	0	965
Additions to equipment in process included in accounts payable	18	42	199
Equipment acquired under capital lease	0	0	153
Interest paid, net of interest capitalized	226	0	0
Warrants issued in connection with debt arrangement	$ 190	$ 0	$ 0

Organization	12 Months Ended
Organization	Dec. 31, 2016
Organization, Consolidation and Presentation of Financial Statements [Abstract]
Organization	Organization Vericel Corporation, a Michigan corporation, which was formerly known as Aastrom Biosciences, Inc. (the Company, Vericel, we, us or our), was incorporated in March 1989 and began employee-based operations in 1991. On May 30, 2014, Vericel completed the acquisition of certain assets and assumed certain liabilities of Sanofi, a French société anonyme (Sanofi), including all of the outstanding equity interests of Genzyme Biosurgery ApS (Genzyme Denmark or the Danish subsidiary) (now known as Vericel Denmark ApS), a wholly-owned subsidiary of Sanofi, and over 250 patent applications of Sanofi and certain of its subsidiaries for purposes of acquiring the portion of the cell therapy and regenerative medicine business (the CTRM Business), which researches, develops, manufactures, markets and sells the Carticel^®, MACI^®, and Epicel^® products. The Company is a fully integrated, commercial-stage biopharmaceutical company dedicated to the identification, development and commercialization of innovative therapies that enable the body to repair and regenerate damaged tissues and organs to restore normal structure and function. Vericel has marketed products and the Company’s goal is to become the leader in cell therapy and regenerative medicine by developing, manufacturing and marketing best-in-class therapies for patients with significant unmet medical needs. The Company operates its business primarily in the U.S. in one reportable segment — the research, product development, manufacture and distribution of patient-specific, expanded cellular therapies for use in the treatment of specific diseases. The accompanying 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 satisfaction of liabilities and commitments in the normal course of business. As of December 31, 2016, the Company has an accumulated deficit of $343.6 million and had a net loss of $19.6 million during 2016. The Company had cash of $23.0 million as of December 31, 2016. The Company expects that existing cash together with its SVB-MidCap facility will be sufficient to support the Company's current operations through at least March 31, 2018. In connection with the SVB-MidCap debt facility, the Company must remain in compliance with a minimum monthly net revenue covenant (determined in accordance with GAAP), measured on a trailing twelve month basis. This covenant was renegotiated with SVB in December 2016 and the December 31, 2016 minimum revenue covenants was changed from $56 million to $52 million. In addition, the December 31, 2017 minimum revenue covenant is set at $60 million. SVB and MidCap also have the ability to call debt based on material adverse change clauses which are subjectively determinable and result in a subjective acceleration clause. If the Company's cash requirements exceed its current expectations, or if it is not in compliance with the monthly net revenue covenants or the subjective acceleration clauses are triggered under the SVB-MidCap Facility, SVB could call the debt immediately resulting in the Company needing additional funds. The Company may seek additional funding through debt or equity financings including the at-the-market agreement in place with Cowen. However, the Company may not be able to obtain financing on acceptable terms or at all. The terms of any financing may adversely affect the holdings or the rights of the Company's shareholders. If the Company needs additional funds and it is unable to obtain funding on a timely basis, the Company may need to significantly curtail its operations including its research and development programs in an effort to provide sufficient funds to continue its operations, which could adversely affect its business prospects.

Summary of Significant Accounting Policies	12 Months Ended
Summary of Significant Accounting Policies	Dec. 31, 2016
Accounting Policies [Abstract]
Summary of Significant Accounting Policies	Summary of Significant Accounting Policies Principles of Consolidation The consolidated financial statements include the accounts of Vericel and its wholly-owned subsidiaries, Marrow Donation, LLC, located in San Diego, California, and Vericel Denmark ApS, in Kastrup, Demark (collectively, the Company). All inter-company transactions and accounts have been eliminated in consolidation. Aastrom Biosciences GmbH ceased operations in 2014 and Marrow Donation, LLC and Vericel Denmark ApS ceased operations in 2015. Use of Estimates The preparation of financial statements in accordance with accounting principles generally accepted in the United States of America requires management to make estimates and assumptions that affect the reported amounts of assets and liabilities and disclosures of contingent assets and liabilities at the date of the financial statements and the reported amounts of expenses during the reported period. Actual results could differ from those estimates. Inventory Inventories are measured at the lower of cost or market value. Cost is calculated based upon standard-cost which approximates costs determined on the first-in, first-out method. We periodically review our inventories for excess or obsolescence and write-down obsolete or other unmarketable inventory to its estimated net realizable value. If the actual net realizable value is less than that estimated by us, or if it is determined that inventory utilization will further diminish based on estimates of demand, additional inventory write-downs may be required. In all cases, product inventory is carried at the lower of cost or its estimated net realizable value. Amounts written down are charged to cost of sales. Accounts Receivable Accounts receivable are initially recorded at the contractual amount owed by the customer. Allowances for doubtful accounts are established when the facts and circumstances indicate that a receivable may not be collectible. Property, Plant and Equipment Property, plant and equipment are initially measured and recognized at acquisition cost, including any directly attributable cost of preparing the asset for its intended use or, in the case of assets acquired in a business combination, at fair value as at the date of the combination. After initial measurement, property, plant and equipment are carried at cost less accumulated depreciation and impairment. Repair and maintenance costs of property, plant and equipment are expensed as incurred. The depreciable value of property, plant and equipment, net of any residual value, is depreciated on a straight line basis over the useful life of the asset. The useful life of an asset is usually equivalent to its economic life. The useful lives of property, plant and equipment are as follows: •Equipment and computers: 3 to 5 years •Furniture and fixtures: 5 years •Building improvements and leasehold improvements: Shorter of the remaining life of the lease or 7 years The costs of assets retired or otherwise disposed of and the accumulated depreciation thereon are removed from the accounts, with any gain or loss realized upon sale or disposal credited or charged to operations. Intangible Assets and Other Long Lived Assets Intangible assets are initially measured at acquisition cost, including any directly attributable costs of preparing the asset for its intended use or, in the case of assets acquired in a business combination at fair value as at the date of the combination. Identifiable intangible assets related to commercial rights are amortized on a straight line basis over their expected useful lives. Amortization of intangible assets is recognized in these financial statements under Costs of product sales. Intangible assets and long-lived assets are assessed for potential impairment when there is evidence that events or changes in circumstances indicate that the carrying amount of an asset may not be recovered. An impairment loss would be recognized when an asset’s fair value, determined based on undiscounted cash flows expected to be generated by the asset, is less than its carrying amount. The impairment loss would be measured as the amount by which the asset’s carrying value exceeds its fair value and recognized in these financial statements. Intangible assets are carried at cost less accumulated amortization and impairment. Revenue Recognition and Net Product Sales Total revenues are comprised of product sales of Carticel, Epicel, MACI, bone marrow and surgical kits. Revenue is recognized when persuasive evidence of an arrangement exists, the goods are shipped or delivered and implanted, depending on shipping terms, title and risk of loss pass to the customer and collectability is reasonably assured. Shipping and handling costs are included as a component of revenue. On June 30, 2016, the Company terminated the agreement with its exclusive distributor for substantially all of its Carticel sales by reducing the scope of its agreement with this distributor. Prior to June 30, 2016, the distributor purchased and took title to Carticel upon shipment of the product and assumed credit and collection risk. The distributor worked with the payers on behalf of patients and surgeons to ensure medical coverage and to obtain reimbursement for Carticel implantation procedures. The Company retained all responsibility for shipment of the product to the surgical suite. In addition, revenue for Carticel was recorded net of a provision for rebates and cash discounts. These rebates and cash discounts were established by the Company at the time of sale, based on historical experience adjusted to reflect known changes in the factors that impact such reserves. For instance, the distributor of Carticel was entitled to chargeback incentives for services that are provided for based on the selling price to the end customer, under specific contractual arrangements. Cash discounts may also be granted for prompt payment. Effective July 1, 2016, the Company transitioned to a direct sales model whereby the Company retains credit and collection risk from the end customer. The Company utilizes a new provider, Dohmen Life Science Services, LLC (DLSS), to provide patient support services but this provider does not purchase and take title to Carticel. The Company recognizes product revenues from sales of Carticel upon implantation as long as (i) there is persuasive evidence that an arrangement exists between ourselves and the customer, (ii) collectability is reasonably assured and (iii) the price is fixed or determinable. Prior authorization or 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's net product revenues are calculated by estimating expected payments for insurance, hospital or patient payments at the time it recognizes the gross revenue. Research and Development Expense Research and development activities represent a significant part of the Company’s business. These expenditures relate to the development of new products, improvement of existing products, technical support of products and compliance with governmental regulations for the protection of consumers and patients. Research and development expenses are expensed as incurred. Stock-Based Compensation The Company’s accounting for stock-based compensation requires it to determine the fair value of common stock issued in the form of stock option awards. The Company uses the value of its common stock at the date of the grant in the calculation of the fair value of its share-based awards. The fair value of stock options held by the employees is determined using a Black-Scholes option valuation method, which is a valuation technique that is acceptable for share-based payment accounting. Key assumptions in determining fair value include volatility, risk-free interest rate, dividend yield and expected term. The assumptions used in calculating the fair value of stock options represent the Company’s best estimates, however; these estimates involve inherent uncertainties and the application of management judgment. As a result, if factors change and different assumptions are used, the stock-based compensation expense could be materially different in the future. In addition, the Company is required to estimate the expected forfeiture rate and only recognize expense for those stock options expected to vest over the service period. The estimated forfeiture rate considers the historical experience of the Company’s stock-based awards. If the actual forfeiture rate is different from the estimate, expense is adjusted accordingly. The Company also has an Employee Stock Purchase Plan (ESPP) which is a compensatory plan. Compensation expense is recorded based on the fair 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. Comprehensive Loss Comprehensive loss is the change in common stockholders’ equity during a period arising from any gain or loss realized related to foreign currency translation. Income Taxes Deferred tax assets are recognized for deductible temporary differences and tax credit carryforwards and deferred tax liabilities are recognized for taxable temporary differences. Deferred tax assets are reduced by a valuation allowance when, in the opinion of management, it is more likely than not that some portion or all of the deferred tax assets will not be realized. Net Loss Per Share Attributable to Common Shareholders Basic earnings (loss) per share is calculated using the two-class method, which is an earnings allocation formula that determines earnings (loss) per share for the holders of the Company’s common shares and holders of the Series B preferred stock. The Series B preferred stock shares contain participation rights in undistributed earnings, but do not share in the losses of the Company. The accumulated but undeclared dividends on the Series B preferred stock of $6.7 million are treated as a reduction of earnings attributable to common shareholders. Financial Instruments The Company’s financial instruments include receivables for which the current carrying amounts approximate market value based upon their short-term nature. Warrants Warrants that could be cash settled or have anti-dilution price protection provisions are recorded as liabilities at their estimated fair value at the date of issuance, with subsequent changes in estimated fair value recorded in other income (expense) in our statement of operations in each subsequent period. Warrants that meet the requirements for equity classification are recorded at fair value with no subsequent remeasurement. In general, warrants are measured using the Black-Scholes valuation model. The methodology is based, in part, upon inputs for which there is little or no observable market data, requiring the Company to develop its own assumptions. The assumptions used in calculating the estimated fair value of the warrants represent our best estimates; however, these estimates involve inherent uncertainties and the application of management judgment. As a result, if factors change and different assumptions are used, the warrant liability for those warrants that could be cash settled or have anti-dilution price protection provisions, the change in estimated fair value could be materially different.

Recent Accounting Pronouncements	12 Months Ended
Recent Accounting Pronouncements	Dec. 31, 2016
New Accounting Pronouncements and Changes in Accounting Principles [Abstract]
Recent Accounting Pronouncements	Recent Accounting Pronouncements Revenue Recognition In May 2014, the Financial Accounting Standards Board (FASB) issued authoritative guidance requiring entities to apply a new model for recognizing revenue from contracts with customers and the reporting of principal versus agent considerations. The guidance will supersede the current revenue recognition guidance and require entities to evaluate their revenue recognition arrangements using a five step model to determine when a customer obtains control of a transferred good or service. The guidance is currently effective for annual reporting periods beginning after December 15, 2017 and may be adopted using a full or modified retrospective application. The Company is currently in the process of evaluating its revenue arrangements under the issued guidance and has not yet determined the impact to its consolidated financial statements. Going Concern Assessment The FASB has issued authoritative guidance for management on how to assess whether substantial doubt exists regarding an entity’s ability to continue as a going concern and guidance on how to prepare related footnote disclosures. The guidance will require management to evaluate whether there are conditions or events that raise substantial doubt about an entity’s ability to continue as a going concern for one year from the date the financial statements are issued. The Company has adopted the new guidance for the period ended December 31, 2016. Refer to Note 1 for further discussion. Presentation and Subsequent Measurement of Debt Issuance Costs The FASB issued guidance which requires entities to present debt issuance costs related to a recognized debt liability as a direct deduction from the carrying amount of that debt liability. For debt issuance costs related to line-of-credit arrangements, companies are able to defer and present debt issuance costs as an asset and subsequently amortize the deferred debt issuance costs ratably over the term of the line-of-credit arrangement, regardless of whether there are any outstanding borrowings on the line-of-credit arrangement. The guidance was effective for annual reporting periods beginning after December 15, 2015 and the Company adopted the guidance as of March 31, 2016 and for future periods. Accounting for Leases The FASB issued guidance to increase transparency and comparability among organizations by recognizing lease assets and lease liabilities on the balance sheet and disclosing key information about leasing arrangements. In accordance with the updated guidance, lessees are required to recognize the assets and liabilities arising from operating leases on the balance sheet. The guidance is effective for annual reporting periods beginning after December 15, 2018, including interim periods within 2018. The Company is currently reviewing the potential impact of adopting the new guidance. Share-based Payment Accounting The FASB issued guidance to simplify the accounting for share-based payment transactions, including the income tax consequences, classification of awards as either equity or liabilities, and classification on the statement of cash flows. The new standard will be effective for us on January 1, 2017. We are currently evaluating the potential impact that this standard may have on our financial position, results of operations and statement of cash flows. Statement of Cash Flows Presentation The FASB issued guidance to address diversity in practice with respect to how certain cash receipts and cash payments are presented and classified in the statement of cash flows. The updated guidance addresses eight specific cash flow issues with the objective of reducing the existing diversity that occurs in practice. The guidance is effective for annual reporting periods beginning after December 15, 2017, including interim periods within 2017. The Company is currently reviewing the potential impact of adopting the new guidance.

- Definition

The entire disclosure of changes in accounting principles, including adoption of new accounting pronouncements, that describes the new methods, amount and effects on financial statement line items.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Glossary Change in Accounting Principle
-URI http://asc.fasb.org/extlink&oid=6507316

Reference 2: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Glossary Direct Effects of a Change in Accounting Principle
-URI http://asc.fasb.org/extlink&oid=66092750

Reference 3: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 250
-SubTopic 10
-Section 50
-Paragraph 3
-URI http://asc.fasb.org/extlink&oid=64853466&loc=d3e22583-107794

Reference 4: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Glossary Indirect Effects of a Change in Accounting Principle
-URI http://asc.fasb.org/extlink&oid=6515603

Reference 5: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 250
-SubTopic 10
-Section 50
-Paragraph 2
-URI http://asc.fasb.org/extlink&oid=64853466&loc=d3e22580-107794

Reference 6: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 270
-SubTopic 10
-Section S99
-Paragraph 1
-Subparagraph (SX 210.10-01.(b)(6))
-URI http://asc.fasb.org/extlink&oid=27015980&loc=d3e46468-122699

Reference 7: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Glossary Accounting Change
-URI http://asc.fasb.org/extlink&oid=6503790

Reference 8: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 250
-SubTopic 10
-Section 50
-Paragraph 1
-URI http://asc.fasb.org/extlink&oid=64853466&loc=d3e22499-107794

Reference 9: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Glossary Retrospective Application
-URI http://asc.fasb.org/extlink&oid=6523989

Reference 10: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 270
-SubTopic 10
-Section 45
-Paragraph 13
-URI http://asc.fasb.org/extlink&oid=68064558&loc=d3e765-108305

Reference 11: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 270
-SubTopic 10
-Section 45
-Paragraph 12
-URI http://asc.fasb.org/extlink&oid=68064558&loc=d3e725-108305

+ Details

Acquisitions

12 Months Ended

Dec. 31, 2016

Business Combinations [Abstract]

Acquisitions

CTRM Business acquisition

On May 30, 2014, Vericel completed its acquisition of certain assets of Sanofi, including all of the outstanding equity interests of Genzyme Denmark, a wholly-owned subsidiary of Sanofi, and over 250 patents and patent applications and assumed certain liabilities for purposes of acquiring portions of the CTRM Business. Vericel is a leader in developing patient-specific expanded cellular therapies for use in the treatment of patients with severe diseases and conditions and the CTRM Business expands the Company’s portfolio of cellular therapies to include products which treat severe burns and as well as cartilage defects. Pursuant to the terms of the asset purchase agreement, the Company paid a total purchase price of $6.5 million, including $4.0 million in cash and a $2.5 million promissory note which was repaid on July 30, 2014.

The total purchase price consideration was as follows:



Acquisition consideration (In thousands):	Fair Value
Cash payment	$	4,000
Promissory note	2,500
Total acquisition consideration	$	6,500

The Company recognized tangible and intangible assets and liabilities acquired based upon their respective estimated fair values as of the acquisition date. The table below shows the fair values assigned to the assets acquired and liabilities assumed. Based on this analysis, the transaction resulted in a bargain purchase gain.

The final purchase price allocation was as follows:



Purchase price allocation (In thousands):	Fair Value
Cash	$	5,050
Accounts receivable	53
Inventory	2,039
Other current assets	192
Accounts payable and accrued expenses	(939		)
Asset retirement obligation	(1,600		)
Property and equipment	1,818
Intangible assets	3,360
Bargain purchase gain	(3,473		)
Total consideration	$	6,500

As part of the acquisition, $5.0 million in cash was received from Sanofi in order to fund the restructuring of the Denmark operations and close the facility. In 2014, the Company implemented its restructuring plans for the Danish subsidiary after the consummation of the acquisition of the CTRM Business and recorded restructuring charges in the U.S. and Denmark of $3.0 million. See Note 5 “Restructuring” below for additional information.

The intangible assets acquired represent commercial use rights for certain products acquired in the transaction. The fair value of $3.4 million was determined using the income approach based on projected cash flows attributed to the commercial rights. In 2016, the Company recorded an impairment related to write-off of the commercial use rights. Upon the approval of MACI in December 2016 and the expected replacement of Carticel with MACI, it was determined the fair value of the Carticel related intangible asset was fully impaired as of December 31, 2016.

Pro forma Financial Information

The following pro forma condensed combined information for the year ended December 31, 2014 is presented as if the acquisition of the CTRM Business had occurred on January 1, 2013.

In management’s opinion, all adjustments necessary to reflect the significant effects of this transaction have been made. These statements are based on assumptions and estimates considered appropriate by management; however, they are not necessarily, and should not be assumed to be, an indication of Vericel’s financial position or results of operations that would have been achieved had the acquisitions been completed as of the dates indicated or that may be achieved in the future.



	Year Ended December 31,
(in thousands)	2014
Pro forma revenue	$	44,906
Pro forma net loss	(30,115		)
Pro forma net loss per share - basic and diluted	(3.10		)

- Definition

The entire disclosure for a business combination (or series of individually immaterial business combinations) completed during the period, including background, timing, and recognized assets and liabilities. The disclosure may include leverage buyout transactions (as applicable).

+ References

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+ Details

Restructuring	12 Months Ended
Restructuring	Dec. 31, 2016
Restructuring and Related Activities [Abstract]
Restructuring	Restructuring Acquisition Restructuring In June 2014, the Company discontinued manufacturing MACI in Denmark and temporarily suspended sales of MACI in Europe. Furthermore, the Company eliminated approximately 80 full time employee positions, which represented approximately 30% of the Company’s current total workforce. As a result, the Company recorded a restructuring charge of $3.0 million for the year ended December 31, 2014, related to the operations in the United States and Denmark, primarily representing cash payments for severance and other personnel-related expenses. Of the total restructuring charge, $2.5 million was recorded in cost of product sales, and $0.5 million was recorded in selling, general and administrative expenses. There was no restructuring reserve as of December 31, 2015 or 2016 as a result of cash payments made for severance and other personnel-related expenses. R&D Restructuring Given the expense required to conduct further development and the Company's focus on growing its existing commercial products and becoming profitable, at this time, the Company does not have current plans to initiate or fund a Phase 3 trial related to the ixCELL-DCM study on its own. As a result of no current need to manufacture ixmyelocel-T at the Ann Arbor facility, the Company recorded an asset retirement obligation of $0.2 million related to the suspension of operations in the Ann Arbor cleanroom facility and recorded a severance accrual of $0.1 million in research and development expenses related to this suspension as of December 31, 2016.

Selected Balance Sheet Components

12 Months Ended

Dec. 31, 2016

Balance Sheet Related Disclosures [Abstract]

Selected Balance Sheet Components

Inventory as of December 31, 2016 and 2015:



(In thousands)	2016		2015
Raw materials	$	3,214	$	1,228
Work-in-process	257		131
Finished goods	17		20
Inventory	$	3,488	$	1,379

Property and Equipment, net as of December 31, 2016 and 2015:



(In thousands)	2016			2015
Machinery and equipment	$	3,150		$	3,280
Furniture, fixtures and office equipment	931			931
Computer equipment and software	3,147			2,662
Leasehold improvements	3,332			2,393
Construction in process	408			421
	10,968			9,687
Less accumulated depreciation	(7,093		)	(5,638		)
Property and Equipment	$	3,875		$	4,049

Depreciation expense for the years ended December 31, 2016, 2015 and 2014 were $1.6 million, $1.3 million, and $0.8 million, respectively.

Intangible assets, net as of December 31, 2016 and 2015:



(In thousands)	2016		2015
Commercial rights	$	—	$	3,360
Less accumulated amortization	—		(443		)
Intangible assets	$	—	$	2,917

Upon the approval of MACI in December 2016 and the replacement of Carticel with MACI, it was determined that the Carticel commercial rights intangible asset was fully impaired as of December 31, 2016. The value of the intangible assets was determined using the income approach based on projected cash flows attributed to the commercial rights. Amortization expense was $0.3 million, $0.3 million and $0.2 million for the years ended December 31, 2016, 2015 and 2014, respectively.

Accrued Expenses as of December 31, 2016 and 2015:



(In thousands)	2016		2015
Bonus	$	2,433	$	1,956
Employee related accruals	1,668		1,341
Accrued expenses	422		75
Other	—		231
Accrued expenses	$	4,523	$	3,603

Debt	12 Months Ended
Debt	Dec. 31, 2016
Debt Disclosure [Abstract]
Debt	Debt On March 8, 2016, the Company entered into a $15.0 million debt financing with Silicon Valley Bank (SVB) which on September 9, 2016, was replaced by an expanded term loan and revolving line of credit agreement with SVB and MidCap Financial Services, or MidCap, which together provide access to up to $20.0 million. The updated debt financing consists of a $4.0 million term loan which was drawn at the closing, a $4.0 million term loan which was drawn upon in November 2016, a $2.0 million term loan which became available upon the FDA's approval of the MACI BLA and which must be drawn by April 12, 2017, and up to $10.0 million of a revolving line of credit. The term loans are interest only (indexed to Wall Street Journal (WSJ) Prime plus 5.00%) until September 1, 2017 followed by 36 equal monthly payments of principal plus interest maturing September 9, 2020. The revolving credit is limited to a borrowing base calculated using eligible accounts receivable and maturing September 9, 2020 with an interest rate indexed to WSJ Prime plus 1.25%. The Company is subject to various financial and nonfinancial covenants including but not limited to a monthly minimum net revenue covenant (determined in accordance with GAAP), measured on a trailing twelve month basis. This covenant was renegotiated with SVB in December 2016 and the December 31, 2016 minimum revenue covenant was changed from $56 million to $52 million. In addition, the December 31, 2017 minimum revenue covenant is set at $60 million. SVB and MidCap have the ability to call debt based on material adverse change clauses which are subjectively determinable and result in a subjective acceleration clause. SVB and MidCap have a shared first priority perfected security interest in all assets of the Company other than intellectual property. As of December 31, 2016, there was an outstanding balance of $8.0 million under the term loan and $2.5 million under the revolving line of credit. The weighted average interest rate on the outstanding term and revolving credit loans as of December 31, 2016 was 7.7%. The remaining capacity under the revolving line of credit as of December 31, 2016 was $7.5 million and we were, and continue to be, in compliance with our financial and non-financial debt covenants. The net revenue financial covenant was updated in an amendment to the credit agreement with SVB and MidCap in December 2016 In addition, warrants were issued in conjunction with the debt agreement as discussed in note 12. In determining whether the debt replacement is to be accounted for as a debt extinguishment or a debt modification, the Company considered whether creditors remained the same or changed and whether the changes in debt terms are substantial. After performing the assessment in accordance with accounting guidance for the modification of debt arrangements, this transaction was determined to be accounted for as a debt modification. As a result, the unamortized deferred financing costs now include $0.1 million from the original issue costs and lender fees and $0.3 million, in new issue costs, lender fees and warrant issuance costs which will be deferred over the life of the new debt arrangement.

Stock-Based Compensation

12 Months Ended

Dec. 31, 2016

Disclosure of Compensation Related Costs, Share-based Payments [Abstract]

Stock-Based Compensation

Stock Option 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 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 granted under these plans expire no later than ten years from the date of grant, and other than those granted to non-employee directors, generally become exercisable over a four period, under a graded-vesting methodology, following the date of grant. The Company generally issues new shares upon the exercise of stock options.

The 2009 Second Amended and Restated Omnibus Incentive Plan (2009 Plan) 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 2009 Plan shall not be less than the fair market value of the Company’s common stock on the date of grant. The 2009 Plan replaced the 1992 Stock Option Plan, the 2001 Stock Option Plan and the Amended and Restated 2004 Equity Incentive Plan (Prior Plans), and no new awards have been granted under the Prior Plans. However, the expiration or forfeiture of options previously granted under the Prior Plans will increase the awards available for issuance under the 2009 Plan.

As of December 31, 2016, there were 1,090,645 shares available for future grant under the 2009 Plan.

Employee Stock Purchase Plan

Employees are able to purchase stock under the Vericel Corporation Employee Stock Purchase Plan (ESPP), which was implemented effective October 1, 2015. The ESPP allows for the issuance of an aggregate of 1,000,000 shares of common stock. 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 January 2017, employees purchased 34,392 shares resulting in proceeds from the sale of common stock of $0.1 million under the ESPP for the first offering period. The total share-based compensation expense for the ESPP for the year ended December 31, 2016 was approximately $0.2 million.

Service-Based Stock Options

During the year ended December 31, 2016, the Company granted 1,110,530 service-based options to purchase common stock. 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 90,000 non-employee options which vest over one year) and have a term of ten years. The weighted average grant-date fair value of service-based options granted during the years ended December 31, 2016, 2015, and 2014 was $2.15, $2.22 and $2.85, respectively.

The net compensation costs recorded for the service-based stock options related to employees and directors (including the impact of the forfeitures) for the years ended December 31, 2016, 2015, and 2014 were $2.3 million, $2.7 million and $0.8 million, respectively.

The fair value of each service-based stock option grant for the reported periods is estimated on the date of the grant using the Black-Scholes option-pricing model using the weighted average assumptions noted in the following table.



	Year Ended December 31,
Service-Based Stock Options	2016	2015	2014
Expected dividend rate	—%	—%	—%
Expected stock price volatility	78.7 – 92.2%	77.4 – 88.1%	82.4 – 88.2%
Risk-free interest rate	1.1 – 2.1%	1.5 – 2.0%	1.7 – 2.2%
Expected life (years)	5.5 – 6.3	5.5 – 6.3	5.5 – 6.3

The following table summarizes the activity for service-based stock options for the indicated periods:



Service-Based Stock Options	Options		Weighted Average Exercise Price		Weighted Average Remaining Contractual Term	Aggregate Intrinsic Value
Outstanding at December 31, 2014	477,530		$	21.74	8.0	$	—
Granted	2,216,600		$	3.11
Exercised	(3,566	)	$	3.02		$	1,000
Expired	(17,791	)	$	40.02
Forfeited	(149,373	)	$	3.35
Outstanding at December 31, 2015	2,523,400		$	36.43	8.7	$	5,000
Granted	1,110,530		$	3.01
Exercised	(39,231	)	$	3.06
Expired	(85,700	)	$	35.76
Forfeited	(153,307	)	$	3.61
Outstanding at December 31, 2016	3,355,692		$	4.66	8.2	$	610
Exercisable at December 31, 2016	1,339,675		$	6.99		$	106

As of December 31, 2016 there was approximately $2.4 million, of total unrecognized compensation cost related to non-vested service-based stock options granted under the 2009 Plan and the Prior Plans. That cost is expected to be recognized over a weighted-average period of 2.8 years.

The total fair value of stock options vested for the years ended December 31, 2016, 2015, and 2014 was $2.2 million, $1.7 million and $1.5 million, respectively.

- Definition

The entire disclosure for compensation-related costs for equity-based compensation, which may include disclosure of policies, compensation plan details, allocation of equity compensation, incentive distributions, equity-based arrangements to obtain goods and services, deferred compensation arrangements, employee stock ownership plan details and employee stock purchase plan details.

+ References + Details

Shareholders' Equity	12 Months Ended
Shareholders' Equity	Dec. 31, 2016
Stockholders' Equity Note [Abstract]
Shareholders' Equity	Shareholders’ Equity 2014 Warrant Exercise Agreement On July 9, 2014, the Company entered into a Warrant Exercise Agreement with one holder of warrants issued by the Company on August 16, 2013 (the 2013 Warrants) to purchase an aggregate of 362,500 shares of the Company’s common stock, no par value. Pursuant to the Warrant Exercise Agreement, the holder agreed to exercise the 2013 Warrants at the existing exercise price of $4.80. The net proceeds to the Company in connection with the exercise of the 2013 Warrants, after deducting a warrant inducement payment and expenses, were approximately $1.5 million. 2014 Stock Purchase Agreement On January 21, 2014, the Company entered into a purchase agreement (Purchase Agreement), together with a registration rights agreement, for the sale of up to $15.0 million of shares of its common stock to Lincoln Park, subject to certain limitations, from time to time over a 30-month period, which began on April 3, 2014 and ended on October 3, 2016. The Company may direct Lincoln Park, at its sole discretion, to purchase up to 50,000 shares of common stock in regular purchases, increasing to amounts of up to 100,000 shares depending upon the closing sale price of the common stock. In addition, the Company may direct Lincoln Park to purchase additional amounts as accelerated purchases if on the date of a regular purchase the closing sale price of the common stock equals or exceeds $3.00 per share. The purchase price of shares of common stock related to the future funding will be based on the prevailing market prices of such shares at the time of sales (or over a period of up to 10 business days leading up to such time), but in no event will shares be sold to Lincoln Park on a day the common stock closing price is less than the floor price of $2.50, subject to adjustment. The Company controls the timing and amount of any sales of common stock to Lincoln Park. The Company’s sales of shares of common stock to Lincoln Park under the Purchase Agreement are limited to no more than the number of shares that would result in the beneficial ownership by Lincoln Park and its affiliates, at any single point in time, of more than 9.99% of the then outstanding shares of the common stock. As of December 31, 2016, the Company issued 985,499 shares of common stock to Lincoln Park and raised gross proceeds of $3.9 million. At-the-Market Sales Agreement On October 10, 2016, we entered into our ATM with Cowen, pursuant to which we may sell shares of our common stock through Cowen and Company, LLC (Cowen), as sales agent, in registered transactions from our shelf registration statement filed in June 2015, for aggregate proceeds of up to $25.0 million. Shares of common stock sold under the ATM are to be sold at market prices. We will pay up to 3% of the gross proceeds to Cowen as a commission. 357,856 shares of common stock have been sold to date under the ATM for net proceeds of $0.8 million and as of December 31, 2016 had remaining capacity of approximately $24.2 million. 2016 Public Equity Offering On December 21, 2016, the Company closed on a public equity offering whereby it sold 7,130,000 shares of common stock at an offering price of $2.75 per share. The proceeds of $18.0 million, net of $1.4 million of underwriters’ discount and $0.2 million of issuance costs consisting primarily of legal and accounting fees, were recorded as a common stock issuance. Treasury Stock On December 23, 2015 Stonepine Capital, LLC (Stonepine) exchanged 1,250,000 shares of the Company's common stock held by Stonepine for 1,250 shares of Series A Convertible Preferred Stock (Preferred Stock). The common stock that was transferred from Stonepine to the Company during the share exchange was reserved as treasury shares. The value transferred to Series A Convertible Preferred Stock of $3.2 million which was equal to the fair market value of the common stock as of December 23, 2015. On November 22, 2016, Stonepine converted the Preferred Stock for 1,250,000 shares of the Company's common stock. Dividends No cash dividends have been declared or paid by the Company since its inception.

- Definition

The entire disclosure for shareholders' equity comprised of portions attributable to the parent entity and noncontrolling interest, including other comprehensive income. Includes, but is not limited to, balances of common stock, preferred stock, additional paid-in capital, other capital and retained earnings, accumulated balance for each classification of other comprehensive income and amount of comprehensive income.

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+ Details

Preferred Stock	12 Months Ended
Preferred Stock	Dec. 31, 2016
Equity [Abstract]
Preferred Stock	Preferred Stock Shareholder Rights Plan In August 2011, the Board of Directors of the Company adopted a Shareholder Rights Plan, as set forth in the Shareholder Rights Agreement between the Company and the rights agent, the purpose of which is, among other things, to enhance the Board’s ability to protect shareholder interests and to ensure that shareholders receive fair treatment in the event any coercive takeover attempt of the Company is made in the future. The Shareholder Rights Plan could make it more difficult for a third party to acquire, or could discourage a third party from acquiring, the Company or a large block of the Company’s common stock. In March 2012, the Board approved an amendment to the Shareholder Rights Plan to enable Eastern Capital Limited and its affiliates to purchase up to 49.9% of the shares of common stock of the Company without becoming an “acquiring person” and thereby triggering the stockholder rights, with the limitations under the Shareholder Rights Plan remaining in effect for all other stockholders of the Company. In connection with the adoption of the Shareholder Rights Plan, the Board of Directors of the Company declared a dividend distribution of one preferred stock purchase right (Right) for each outstanding share of common stock to stockholders of record as of the close of business on August 15, 2011. In addition, one Right will automatically attach to each share of common stock issued between August 15, 2011 and the distribution date. As a result of the October 2013 reverse stock split, the number of Rights associated with each share of common stock was automatically proportionately adjusted so that (i) twenty rights were then associated with each outstanding share of common stock and (ii) so long as the Rights are attached to the common stock, twenty rights shall be deemed to be delivered for each share of common stock issued or transferred by the Company in the future. The Rights currently are not exercisable and are attached to and trade with the outstanding shares of common stock. Each Right entitles the registered holder of common stock to purchase from the Company a unit consisting of one ten-thousandth of a share (Unit) of Series A Junior Participating Preferred Stock, no par value per share, at a cash exercise prices of $30.00 per Unit. There are currently 45,000 shares authorized and zero issued and outstanding. Under the Shareholder Rights Plan, the Rights become exercisable if a person or group becomes an “acquiring person” by acquiring 15% or more of the outstanding shares of common stock or if a person or group commences a tender offer that would result in that person owning 15% or more of the common stock. If a person or group becomes an “acquiring person,” each holder of a Right (other than the acquiring person and its affiliates, associates and transferees) would be entitled to purchase, at the then-current exercise price, such number of shares of the Company’s preferred stock which are equivalent to shares of common stock having a value of twice the exercise price of the Right. If the Company is acquired in a merger or other business combination transaction after any such event, each holder of a Right would then be entitled to purchase, at the then-current exercise price, shares of the acquiring company’s common stock having a value of twice the exercise price of the Right. The Rights may be redeemed in whole, but not in part, at a price of $0.001 per Right (payable in cash, common stock or other consideration deemed appropriate by the Board of Directors) by the Board of Directors only until the earlier of (i) the time at which any person becomes an “acquiring person” or (ii) the expiration date of the Rights Agreement. Immediately upon the action of the Board of Directors ordering redemption of the Rights, the Right will terminate and thereafter the only right of the holders of Rights will be to receive the redemption price. The Rights will expire at the close of business on August 15, 2021, unless previously redeemed or exchanged by the Company as described above. Series B Convertible Preferred Stock On March 9, 2012, the Company completed the sale of 12,308 shares of Series B-1 Non-Voting Convertible Preferred Stock (Series B-1 preferred stock) at an offering price of $3,250 per share. In addition to the Series B-1 preferred stock, which was issued at the closing, the Company also authorized Series B-2 Voting Convertible preferred Stock (Series B-2 preferred stock). The Series B-1 preferred stock and Series B-2 preferred stock collectively are referred to as the Series B preferred stock. The Series B preferred stock is convertible, at the option of the holder thereof at any time after the five year anniversary of the closing of the offering, into shares of common stock at a conversion price of $3.25 per share of common stock, at a conversion ratio of one share of preferred stock for fifty shares of common stock. At any time after the five year anniversary of issuance, the Company may elect to convert any or all outstanding shares of Series B preferred stock into shares of common stock, subject to certain limitations. Dividends on the Series B preferred stock will be cumulative and compound daily, at a rate of 11.5% per annum, payable upon conversion, liquidation, redemption or other similar events, and payable in cash or Series B-1 preferred stock until the five year anniversary of issuance. As of December 31, 2016, there are 455,308 accumulated but undeclared Series B-1 dividends. Unless prohibited by Michigan law governing distributions to shareholders, the Series B-1 preferred stock shall be redeemable at the option of holder of the Series B-1 preferred stock commencing at any time after the five years anniversary of issuance, liquidation, winding up, dissolution or other similar events, subject to certain terms and limitations. On March 9, 2017 all shares of the Series B preferred stock were converted to common stock. See note 18 for further discussion. The Series B preferred stock does not, in its entirety, require liability classification and was evaluated for embedded features to determine if those features require bifurcation and separate classification as derivative liabilities. The Series B preferred stock host contract was evaluated for equity or mezzanine classification based upon the nature of the redemption and conversion features. Generally, any feature that could require cash redemption for matters not within the Company’s control, irrespective of probability of the event occurring, requires classification outside of shareholders’ equity. The Series B preferred stock was initially recorded as mezzanine in the Consolidated Balance Sheets and was accreted to its redemption value through charges to accumulated deficit using the effective interest method. On August 12, 2013, the Company amended the Series B preferred stock agreement to remove the cash redemption provision, modify the liquidation preferences for the Series B-2 preferred stock and to increase the redemption price for the Series B-1 preferred stock. The redemption price, prior to the five year anniversary, was equal to $7,430 multiplied by the number of Series B-1 preferred shares redeemed minus the Company’s closing stock price multiplied by the number of common shares into which the outstanding Series B-2 preferred stock are convertible. The redemption price, after the five year anniversary, was the amount equal to the greater of the Series B offering price plus accrued dividends or the conversion value in common stock. As a result of the amendment to the agreement, the total amount of $38.4 million Series B preferred stock was reclassified from mezzanine into shareholders’ equity. Series A Convertible Preferred Stock On December 18, 2015, Vericel entered into a Securities Exchange Agreement (Exchange Agreement) with Stonepine pursuant to which Stonepine exchanged an aggregate of 1,250,000 shares of its common stock held by Stonepine for 1,250 shares of the Company’s Series A Non-Voting Convertible Preferred Stock (the Exchange). The Exchange closed on December 23, 2015. In connection with the Exchange, the Company designated 1,250 shares of its authorized and unissued preferred stock as Series A Convertible Preferred Stock. Each share of Series A Convertible Preferred Stock is convertible into 1,000 shares of its common stock at any time at the holder’s option. On November 22, 2016, Stonepine converted the Preferred Stock for 1,250,000 shares of the Company's common stock.

Net Loss Per Common Share

12 Months Ended

Dec. 31, 2016

Earnings Per Share [Abstract]

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:



	Year Ended December 31,
(Amounts in thousands, except per share amounts)	2016			2015			2014
Numerator:
Net loss	$	(19,566	)	$	(16,340	)	$	(19,920	)
Less: earnings attributable to convertible preferred stock	7,579			6,736			6,005
Numerator of basic and diluted EPS	$	(27,145	)	$	(23,076	)	$	(25,925	)
Denominator:
Denominator for basic and diluted EPS: weighted-average common shares outstanding	23,093			23,760			11,642
Net loss per share attributable to common shareholders (basic and diluted)	$	(1.18	)	$	(0.97	)	$	(2.23	)

Common equivalent shares and treasury stock are not included in the diluted per share calculation where the effect of their inclusion would be anti-dilutive. The aggregate number of common equivalent shares (related to options, warrants, preferred stock and treasury stock) that have been excluded from the computations of diluted net loss per common share for the years ended December 31, 2016, 2015 and 2014 was 5.3 million, 6.7 million and 2.3 million, respectively.

Stock Purchase Warrants

12 Months Ended

Dec. 31, 2016

Warrants and Rights Note Disclosure [Abstract]

Stock Purchase Warrants

The Company has historically issued warrants to purchase shares of the Company’s common stock in connection with certain of its common stock offerings and in September 2016 the Company issued warrants in connection with the updated debt agreement (September 2016 Warrants) discussed in note7. The warrants issued in August 2013 (August 2013 Warrants) include anti-dilution price protection provisions that could require cash settlement of the warrants and accordingly requiring the warrants to be recorded as liabilities of the Company at the estimated fair value at the date of issuance, with changes in estimated fair value recorded as income or expense (non-cash) in the Company’s statement of operations in each subsequent period. The September 2016 Warrants meet the requirements for equity classification. The following table describes the outstanding warrants:



	August 2013 Warrants	September 2016 Warrants
Exercise price	$4.80	$2.48
Expiration date	August 16, 2018	September 9, 2022
Total shares issuable on exercise	724,950	117,074

On September 9, 2016, the Company issued 117,074 warrants to two holders in conjunction with the loan agreement described in note 7. The initial valuation of the September 2016 Warrants was recorded as debt issuance costs and is being amortized over the remaining life of the loan agreement to interest expense. The September 2016 Warrants are treated as equity instruments recorded at fair value with no subsequent remeasurement. Pursuant to the warrants, the holders may exercise their warrants for an aggregate of 117,074 shares of the Company’s common stock.

The fair value of the warrants described in the table above is measured using the Black-Scholes valuation model. Inherent in the Black-Scholes valuation model are assumptions related to expected stock-price volatility, expected life, risk-free interest rate and dividend yield. The Company estimates the volatility of its common stock based on historical volatility that matches the expected remaining life of the warrants. The risk-free interest rate is based on the U.S. Treasury zero-coupon yield curve on the grant date for a maturity similar to the expected remaining life of the warrants. The expected life of the warrants is assumed to be equivalent to their remaining contractual term. The dividend rate is based on the historical rate, which the Company anticipates to remain at zero.

The assumptions used by the Company are summarized in the following table:



August 2013 Warrants	December 31, 2016			December 31, 2015
Closing stock price	$	3.00		$	2.58
Expected dividend yield	—		%	—		%
Expected stock price volatility	97.9		%	91.4		%
Risk-free interest rate	1.03		%	1.31		%
Expected life (years)	1.62			2.63



September 2016 Warrants	September 9, 2016
Closing stock price	$	2.20
Expected dividend rate	—		%
Expected stock price volatility	89.8		%
Risk-free interest rate	1.4		%
Expected life (years)	6.00

Fair Value Measurements

12 Months Ended

Dec. 31, 2016

Fair Value Disclosures [Abstract]

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).

The following table summarizes the valuation of the Company’s financial instruments that are measured at fair value on a recurring basis:



	December 31, 2016								December 31, 2015
	Fair value measurement category								Fair value measurement category
(In thousands)	Total		Level 1		Level 2		Level 3		Total		Level 1		Level 2		Level 3
Liabilities:
Warrant liabilities	$	757	$	—	$	757	$	—	$	757	$	—	$	757	$	—

The fair values of the warrants are measured using the Black-Scholes valuation model. See Note 12 for further discussion of the significant observable inputs use to measure the warrant liabilities.

The following table summarizes the change in the estimated fair value of the Company’s warrant liabilities:



Warrant Liabilities (In thousands)
Balance at December 31, 2014	$	1,081
Warrant exercises	—
Decrease in fair value	(324		)
Balance at December 31, 2015	757
Change in fair value	—
Balance at December 31, 2016	$	757

- Definition

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

+ References + Details

Income Taxes

12 Months Ended

Dec. 31, 2016

Income Tax Disclosure [Abstract]

Income Taxes

Income (loss) before income taxes for U.S and non-U.S operations was as follows:



	Year Ended December 31,
	2016			2015			2014
U.S. loss	$	(19,302	)	$	(16,235	)	$	(18,078	)
Non U.S. loss	(264		)	(105		)	(1,842		)
	$	(19,566	)	$	(16,340	)	$	(19,920	)

A reconciliation of income taxes computed using the federal statutory rate to the taxes reported in the consolidated statements of operations is as follows:



	Year Ended December 31,
(In thousands)	2016			2015			2014
Loss before income taxes	$	(19,566	)	$	(16,340	)	$	(19,920	)
Federal statutory rate	34		%	34		%	34		%
Taxes computed at federal statutory rate	(6,652		)	(5,556		)	(6,773		)
State taxes (net of federal benefit)	(1,016		)	(392		)	(463		)
Warrants	—			(118		)	(10		)
Nondeductible stock compensation	549			543			48
State Rate Change	(614		)	—			—
Michigan NOL benefit	—			—			—
Net operating loss expirations	—			—			655
Write-off of Section 382 limited NOL’s	—			—			67,781
Write-off of Section 383 limited R&D credits	—			—			1,600
Other	56			57			352
Adjustment to prior year filed returns	—			(5,203		)	—
Change in valuation allowance	7,677			10,669			(63,190		)
Reported income taxes	$	—		$	—		$	—

Deferred tax assets consist of the following:



	Year Ended December 31,
(In thousands)	2016			2015
Net operating loss carryforwards	$	10,343		$	13,998
Employee benefits and stock compensation	2,896			2,485
Research and development costs	13,659			4,903
Fixed assets	700			453
Intangible assets	—			(477		)
Inventory reserve	1,898			510
Other, net	196			143
Total deferred tax assets	29,692			22,015
Valuation allowance	(29,692		)	(22,015		)
Net deferred tax assets	$	—		$	—

In 2014, the Company underwent a change in control as defined by Section 382 of the Internal Revenue Code. A change in control is generally defined as a cumulative change of 50% or more in the ownership positions of certain stockholders during a rolling three year period. This change in control resulted in substantial limitations being placed on certain tax attributes including net operating losses and tax credit carryforwards. The limitations are computed based upon several variable factors including the value of the Company on the date of the change in control. The projected annual limitation on the use of the net operating losses that existed prior to September 17, 2014 is $0.8 million. As a result, a significant portion of the net operating losses and tax credit carryforwards will expire prior to their utilization, regardless of the level of future profitability. Accordingly, the Company reduced its net operating losses and tax credit carryforwards in 2014 (with a corresponding adjustment to the valuation allowance) to reflect the amount available to offset future profits. There was not a change of control in 2015 or 2016.

As of December 31, 2016, the Company’s U.S. federal, and state tax net operating loss carryforwards available to offset future profits, after considering the aforementioned annual Section 382 limit, are $28.6 million and $11.5 million, respectively. These net operating loss carryforwards will expire between 2017 and 2036.

In accordance with the accounting guidance for income taxes, the Company estimated whether recoverability of its deferred tax assets is “more likely than not,” based on forecasts of taxable income in the related tax jurisdictions. In this estimate, the Company uses historical results, projected future operating results based upon approved business plans, eligible carry forward periods, tax planning opportunities and other relevant considerations. Based on these factors, including historical losses incurred by the Company, a full valuation allowance for the deferred tax assets, including the deferred tax assets for the aforementioned net operating losses and credits, has been provided since they are not more likely than not to be realized. If the Company achieves profitability, these deferred tax assets may be available to offset future income taxes. The change in the valuation allowance was an increase of $7.7 million and $10.7 million for the years ended December 31, 2016 and 2015, respectively.

The Company assesses uncertain tax positions in accordance with the guidance for accounting for uncertain tax positions. This pronouncement prescribes a recognition threshold and measurement methodology for recording within the financial statements uncertain tax positions taken, or expected to be taken, in the Company’s income tax returns. To the extent the uncertain tax positions do not meet the “more likely than not” threshold, the Company has derecognized such positions. To the extent the uncertain tax positions meet the “more likely than not” threshold, the Company has measured and recorded the highest probable benefit, and have established appropriate reserves for benefits that exceed the amount likely to be sustained upon examination. The Company currently has not recorded any uncertain tax positions and does not anticipate that the unrecognized tax benefits will significantly increase or decrease within the next twelve months.

The Company files U.S. federal, Alabama, California, Colorado, Illinois, Massachusetts, Michigan, New Jersey, Tennessee and Texas income tax returns. Due to the Company’s net operating loss carryforwards, Federal income tax returns from incorporation are still subject to examination. Michigan tax returns for the year ended December 31, 2012 and forward are subject to examination. Massachusetts tax returns for the year ended December 31, 2014 and forward are subject to examination.

Employee Savings Plan	12 Months Ended
Employee Savings Plan	Dec. 31, 2016
Compensation and Retirement Disclosure [Abstract]
Employee Savings Plan	Employee Savings Plan The Company has a 401(k) savings plan that allows participating employees to contribute a portion of their salary, subject to annual limits and minimum qualifications. The Board may, at its sole discretion, approve Company matching contributions to the plan. The Company made contributions of $0.6 million, $0.5 million and $0.3 million for the years ended December 31, 2016, 2015 and 2014, respectively.

Concentration of Credit	12 Months Ended
Concentration of Credit	Dec. 31, 2016
Risks and Uncertainties [Abstract]
Concentration of Credit	Concentration of Credit On June 30, 2016, the Company terminated its agreement with the distributor for a significant portion of its Carticel sales. Prior to June 30, 2016, the Company sold Carticel to a distributor, which subsequently resold Carticel to patients and healthcare providers. The Company has transitioned to a new provider, Dohmen Life Science Services, LLC (DLSS) who provides a patient support services program but does not act as a distributor. The Company's receivables risk is now spread among various hospitals, individual patients, and third-party payers and therefore, the concentration of credit risk shifted for the Company. Revenue from one customer, a distributor in the U.S., represented 31% and 66% of total revenue during the years ended December 31, 2016 and 2015, respectively. Accounts receivable from the same customer accounted for 1% and 76% of the outstanding accounts receivable as of December 31, 2016 and 2015, respectively. The next largest customer represented 11% and 12% of revenue for the year ended December 31, 2016 and 2015, respectively. Accounts receivable from the next largest customer accounted for 5% and 8% of the outstanding accounts receivable as of December 31, 2016 and 2015, respectively.

Commitments and Contingencies

12 Months Ended

Dec. 31, 2016

Commitments and Contingencies Disclosure [Abstract]

Commitments and Contingencies

Licenses, Royalties and Collaborative Agreements

Corning Incorporated — In December 2002, the Company entered into an agreement with Corning Incorporated (Corning) that granted Corning an exclusive sublicense relating to the Company’s cell transfection technology. Under the terms of the agreement, the Company retains exclusive rights to the applications of the technologies involving cells for therapeutic applications. In addition, the agreement provides for future royalty payments on net sales of licensed products sold under the sublicense amounting to 5% of such sales up to $50.0 million. However, the Company does not expect to receive material revenue from this source for several years, if ever.

RealBio Technologies — In May 2009, the Company entered into an agreement with RealBio Technologies, Inc. (RealBio) that granted RealBio an exclusive license to utilize our technology outside of the Company’s core area of focus - human regenerative medicine. In return for this license, the Company received a minority equity interest in RealBio, which was not material as of December 31, 2016 or 2015. The Company received a plan of complete liquidation, dissolution and termination of the existence of RealBio under which RealBio was to be liquidated no later than November 30, 2016. The Company entered into a license assignment, assumption, amendment and consent agreement as of January 23, 2017 pursuant to which RealBio’s license was transferred to RealBio Holdings LLC and amended to add royalties on future sales of licensed products.

Matricel — In October 2015, the Company signed a long-term supply agreement with Matricel GmbH for the ACI-Maix collagen membrane used in the manufacture of MACI™. Matricel supplied ACI-Maix membranes used in the production of MACI when it was previously marketed outside the U.S. by Genzyme Corporation, a Sanofi company. Under the agreement, the Company has committed to purchase annually approximately $0.6 million per year. The agreement is effective until December 31, 2022 and contains a 5-year renewal option by the Company and an additional 5-year automatic renewal, unless otherwise terminated.

Manufacture, Supply and Other Agreements — The Company has entered into various agreements relating to the manufacture of its products and the supply of certain components. If the manufacturing or supply agreements expire or are otherwise terminated, the Company may not be able to identify and obtain ancillary materials that are necessary to develop its product and such expiration and termination could have a material effect on the Company’s business.

Contractual Obligations

The Company leases facilities in Ann Arbor, Michigan and Cambridge, Massachusetts. In March 2016, the Company amended its current lease in Cambridge to extend the terms until February 2022. Under the amendment, the landlord will contribute approximately $2.0 million toward the cost of tenant improvements. The contribution toward the cost of tenant improvements is recorded as deferred rent on the Company's consolidated balance sheet and is amortized to our consolidated statement of operations as reductions to rent expense over the lease term. As of December 31, 2016, the Company has recorded a tenant improvement of $0.9 million. In addition to the property leases, the Company also leases an offsite warehouse, various vehicles and computer equipment.

Future minimum payments related to Vericel’s operating and capital leases are as follows:



			Payments Due by Period
Contractual Obligations	Total		2017		2018		2019		2020		2021		More than 5 Years
Operating leases	$	23,835	$	5,138	$	4,658	$	4,319	$	4,413	$	4,546	$	761
Purchase commitments	7,770		2,268		2,268		1,434		600		600		600
Capital leases	75		43		32
Total	$	31,680	$	7,449	$	6,958	$	5,753	$	5,013	$	5,146	$	1,361

Rent expense for the years ended December 31, 2016, 2015 and 2014, was $4.8 million, $4.9 million and $2.5 million, respectively.

Subsequent Events	12 Months Ended
Subsequent Events	Dec. 31, 2016
Subsequent Events [Abstract]
Subsequent Events	Subsequent Events On February 10, 2017, the Company sent notice to Eastern Capital Limited (Eastern), an existing holder of shares of the Company’s Series B-1 Non-Voting Convertible Preferred Stock or Series B-2 Voting Convertible Preferred Stock (Preferred Stock), informing Eastern of the Company's election to convert all 12,308 of the outstanding shares of Preferred Stock held by Eastern, plus 9,570 shares of Preferred Stock in accumulated but undeclared dividends thereon, into 1,093,892 shares of the Company's common stock pursuant to the terms of the Amended and Restated Certificate of Designations, Preferences and Rights of Series B-1 Non-Voting Preferred Stock and Series B-2 Voting Preferred Stock of the Company (Mandatory Conversion). After the Mandatory Conversion on March 9, 2017, no shares of Preferred Stock of the Company will remain outstanding.

Supplementary Quarterly Financial Information (unaudited)

12 Months Ended

Dec. 31, 2016

Quarterly Financial Information Disclosure [Abstract]

Supplementary Quarterly Financial Information (unaudited)

Quarterly earnings per share amounts may not sum to the totals for each of the years, since quarterly computations are based on weighted average common shares outstanding during each quarter.



In thousands, except per share data)	First Quarter			Second Quarter			Third Quarter			Fourth Quarter			Year
2016
Revenues	$	14,108		$	12,823		$	10,929		$	16,523		$	54,383
Gross profit	7,548			5,523			4,073			8,932			26,076
Loss from operations	(1,992		)	(4,984		)	(6,380		)	(5,889		)	(19,245		)
Net loss	(3,650		)	(3,044		)	(6,675		)	(6,197		)	(19,566		)
Net loss per share (Basic and Diluted)	(0.24		)	(0.22		)	(0.38		)	(0.34		)	(1.18		)
2015
Revenues	$	10,849		$	13,590		$	11,309		$	15,420		$	51,168
Gross profit (loss)	5,281			6,689			4,537			8,191			24,698
Loss from operations	(4,572		)	(2,265		)	(4,877		)	(4,957		)	(16,671		)
Net loss	(4,862		)	(2,152		)	(4,416		)	(4,910		)	(16,340		)
Net loss per share (Basic and Diluted)	(0.27		)	(0.16		)	(0.26		)	(0.28		)	(0.97		)

Summary of Significant Accounting Policies (Policies)	12 Months Ended
Summary of Significant Accounting Policies (Policies)	Dec. 31, 2016
Accounting Policies [Abstract]
Principles of Consolidation	Principles of Consolidation The consolidated financial statements include the accounts of Vericel and its wholly-owned subsidiaries
Use of Estimates	Use of Estimates The preparation of financial statements in accordance with accounting principles generally accepted in the United States of America requires management to make estimates and assumptions that affect the reported amounts of assets and liabilities and disclosures of contingent assets and liabilities at the date of the financial statements and the reported amounts of expenses during the reported period. Actual results could differ from those estimates.
Inventory	Inventory Inventories are measured at the lower of cost or market value. Cost is calculated based upon standard-cost which approximates costs determined on the first-in, first-out method. We periodically review our inventories for excess or obsolescence and write-down obsolete or other unmarketable inventory to its estimated net realizable value. If the actual net realizable value is less than that estimated by us, or if it is determined that inventory utilization will further diminish based on estimates of demand, additional inventory write-downs may be required. In all cases, product inventory is carried at the lower of cost or its estimated net realizable value. Amounts written down are charged to cost of sales.
Accounts Receivable	Accounts Receivable Accounts receivable are initially recorded at the contractual amount owed by the customer. Allowances for doubtful accounts are established when the facts and circumstances indicate that a receivable may not be collectible.
Property, Plant and Equipment	Property, Plant and Equipment Property, plant and equipment are initially measured and recognized at acquisition cost, including any directly attributable cost of preparing the asset for its intended use or, in the case of assets acquired in a business combination, at fair value as at the date of the combination. After initial measurement, property, plant and equipment are carried at cost less accumulated depreciation and impairment. Repair and maintenance costs of property, plant and equipment are expensed as incurred. The depreciable value of property, plant and equipment, net of any residual value, is depreciated on a straight line basis over the useful life of the asset. The useful life of an asset is usually equivalent to its economic life. The useful lives of property, plant and equipment are as follows: •Equipment and computers: 3 to 5 years •Furniture and fixtures: 5 years •Building improvements and leasehold improvements: Shorter of the remaining life of the lease or 7 years The costs of assets retired or otherwise disposed of and the accumulated depreciation thereon are removed from the accounts, with any gain or loss realized upon sale or disposal credited or charged to operations.
Intangible Assets and Other Long Lived Assets	Intangible Assets and Other Long Lived Assets Intangible assets are initially measured at acquisition cost, including any directly attributable costs of preparing the asset for its intended use or, in the case of assets acquired in a business combination at fair value as at the date of the combination. Identifiable intangible assets related to commercial rights are amortized on a straight line basis over their expected useful lives. Amortization of intangible assets is recognized in these financial statements under Costs of product sales. Intangible assets and long-lived assets are assessed for potential impairment when there is evidence that events or changes in circumstances indicate that the carrying amount of an asset may not be recovered. An impairment loss would be recognized when an asset’s fair value, determined based on undiscounted cash flows expected to be generated by the asset, is less than its carrying amount. The impairment loss would be measured as the amount by which the asset’s carrying value exceeds its fair value and recognized in these financial statements. Intangible assets are carried at cost less accumulated amortization and impairment.
Revenue Recognition and Net Product Sales	Revenue Recognition and Net Product Sales Total revenues are comprised of product sales of Carticel, Epicel, MACI, bone marrow and surgical kits. Revenue is recognized when persuasive evidence of an arrangement exists, the goods are shipped or delivered and implanted, depending on shipping terms, title and risk of loss pass to the customer and collectability is reasonably assured. Shipping and handling costs are included as a component of revenue. On June 30, 2016, the Company terminated the agreement with its exclusive distributor for substantially all of its Carticel sales by reducing the scope of its agreement with this distributor. Prior to June 30, 2016, the distributor purchased and took title to Carticel upon shipment of the product and assumed credit and collection risk. The distributor worked with the payers on behalf of patients and surgeons to ensure medical coverage and to obtain reimbursement for Carticel implantation procedures. The Company retained all responsibility for shipment of the product to the surgical suite. In addition, revenue for Carticel was recorded net of a provision for rebates and cash discounts. These rebates and cash discounts were established by the Company at the time of sale, based on historical experience adjusted to reflect known changes in the factors that impact such reserves. For instance, the distributor of Carticel was entitled to chargeback incentives for services that are provided for based on the selling price to the end customer, under specific contractual arrangements. Cash discounts may also be granted for prompt payment. Effective July 1, 2016, the Company transitioned to a direct sales model whereby the Company retains credit and collection risk from the end customer. The Company utilizes a new provider, Dohmen Life Science Services, LLC (DLSS), to provide patient support services but this provider does not purchase and take title to Carticel. The Company recognizes product revenues from sales of Carticel upon implantation as long as (i) there is persuasive evidence that an arrangement exists between ourselves and the customer, (ii) collectability is reasonably assured and (iii) the price is fixed or determinable. Prior authorization or 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's net product revenues are calculated by estimating expected payments for insurance, hospital or patient payments at the time it recognizes the gross revenue.
Research and Development Expense	Research and Development Expense Research and development activities represent a significant part of the Company’s business. These expenditures relate to the development of new products, improvement of existing products, technical support of products and compliance with governmental regulations for the protection of consumers and patients. Research and development expenses are expensed as incurred.
Stock-Based Compensation	Stock-Based Compensation The Company’s accounting for stock-based compensation requires it to determine the fair value of common stock issued in the form of stock option awards. The Company uses the value of its common stock at the date of the grant in the calculation of the fair value of its share-based awards. The fair value of stock options held by the employees is determined using a Black-Scholes option valuation method, which is a valuation technique that is acceptable for share-based payment accounting. Key assumptions in determining fair value include volatility, risk-free interest rate, dividend yield and expected term. The assumptions used in calculating the fair value of stock options represent the Company’s best estimates, however; these estimates involve inherent uncertainties and the application of management judgment. As a result, if factors change and different assumptions are used, the stock-based compensation expense could be materially different in the future. In addition, the Company is required to estimate the expected forfeiture rate and only recognize expense for those stock options expected to vest over the service period. The estimated forfeiture rate considers the historical experience of the Company’s stock-based awards. If the actual forfeiture rate is different from the estimate, expense is adjusted accordingly. The Company also has an Employee Stock Purchase Plan (ESPP) which is a compensatory plan. Compensation expense is recorded based on the fair 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.
Comprehensive Loss	Comprehensive Loss Comprehensive loss is the change in common stockholders’ equity during a period arising from any gain or loss realized related to foreign currency translation.
Income Taxes	Income Taxes Deferred tax assets are recognized for deductible temporary differences and tax credit carryforwards and deferred tax liabilities are recognized for taxable temporary differences. Deferred tax assets are reduced by a valuation allowance when, in the opinion of management, it is more likely than not that some portion or all of the deferred tax assets will not be realized.
Net Loss Per Share Attributable to Common Shareholders	Net Loss Per Share Attributable to Common Shareholders Basic earnings (loss) per share is calculated using the two-class method, which is an earnings allocation formula that determines earnings (loss) per share for the holders of the Company’s common shares and holders of the Series B preferred stock. The Series B preferred stock shares contain participation rights in undistributed earnings, but do not share in the losses of the Company. The accumulated but undeclared dividends on the Series B preferred stock of $6.7 million are treated as a reduction of earnings attributable to common shareholders.
Financial Instruments	Financial Instruments The Company’s financial instruments include receivables for which the current carrying amounts approximate market value based upon their short-term nature.
Warrants	Warrants Warrants that could be cash settled or have anti-dilution price protection provisions are recorded as liabilities at their estimated fair value at the date of issuance, with subsequent changes in estimated fair value recorded in other income (expense) in our statement of operations in each subsequent period. Warrants that meet the requirements for equity classification are recorded at fair value with no subsequent remeasurement. In general, warrants are measured using the Black-Scholes valuation model. The methodology is based, in part, upon inputs for which there is little or no observable market data, requiring the Company to develop its own assumptions. The assumptions used in calculating the estimated fair value of the warrants represent our best estimates; however, these estimates involve inherent uncertainties and the application of management judgment. As a result, if factors change and different assumptions are used, the warrant liability for those warrants that could be cash settled or have anti-dilution price protection provisions, the change in estimated fair value could be materially different.
Recent Accounting Pronouncements	Recent Accounting Pronouncements Revenue Recognition In May 2014, the Financial Accounting Standards Board (FASB) issued authoritative guidance requiring entities to apply a new model for recognizing revenue from contracts with customers and the reporting of principal versus agent considerations. The guidance will supersede the current revenue recognition guidance and require entities to evaluate their revenue recognition arrangements using a five step model to determine when a customer obtains control of a transferred good or service. The guidance is currently effective for annual reporting periods beginning after December 15, 2017 and may be adopted using a full or modified retrospective application. The Company is currently in the process of evaluating its revenue arrangements under the issued guidance and has not yet determined the impact to its consolidated financial statements. Going Concern Assessment The FASB has issued authoritative guidance for management on how to assess whether substantial doubt exists regarding an entity’s ability to continue as a going concern and guidance on how to prepare related footnote disclosures. The guidance will require management to evaluate whether there are conditions or events that raise substantial doubt about an entity’s ability to continue as a going concern for one year from the date the financial statements are issued. The Company has adopted the new guidance for the period ended December 31, 2016. Refer to Note 1 for further discussion. Presentation and Subsequent Measurement of Debt Issuance Costs The FASB issued guidance which requires entities to present debt issuance costs related to a recognized debt liability as a direct deduction from the carrying amount of that debt liability. For debt issuance costs related to line-of-credit arrangements, companies are able to defer and present debt issuance costs as an asset and subsequently amortize the deferred debt issuance costs ratably over the term of the line-of-credit arrangement, regardless of whether there are any outstanding borrowings on the line-of-credit arrangement. The guidance was effective for annual reporting periods beginning after December 15, 2015 and the Company adopted the guidance as of March 31, 2016 and for future periods. Accounting for Leases The FASB issued guidance to increase transparency and comparability among organizations by recognizing lease assets and lease liabilities on the balance sheet and disclosing key information about leasing arrangements. In accordance with the updated guidance, lessees are required to recognize the assets and liabilities arising from operating leases on the balance sheet. The guidance is effective for annual reporting periods beginning after December 15, 2018, including interim periods within 2018. The Company is currently reviewing the potential impact of adopting the new guidance. Share-based Payment Accounting The FASB issued guidance to simplify the accounting for share-based payment transactions, including the income tax consequences, classification of awards as either equity or liabilities, and classification on the statement of cash flows. The new standard will be effective for us on January 1, 2017. We are currently evaluating the potential impact that this standard may have on our financial position, results of operations and statement of cash flows. Statement of Cash Flows Presentation The FASB issued guidance to address diversity in practice with respect to how certain cash receipts and cash payments are presented and classified in the statement of cash flows. The updated guidance addresses eight specific cash flow issues with the objective of reducing the existing diversity that occurs in practice. The guidance is effective for annual reporting periods beginning after December 15, 2017, including interim periods within 2017. The Company is currently reviewing the potential impact of adopting the new guidance.

Acquisitions (Tables)

12 Months Ended

Dec. 31, 2016

Business Combinations [Abstract]

Schedule of total purchase price consideration

The total purchase price consideration was as follows:



Acquisition consideration (In thousands):	Fair Value
Cash payment	$	4,000
Promissory note	2,500
Total acquisition consideration	$	6,500

Schedule of final purchase price allocation

The final purchase price allocation was as follows:



Purchase price allocation (In thousands):	Fair Value
Cash	$	5,050
Accounts receivable	53
Inventory	2,039
Other current assets	192
Accounts payable and accrued expenses	(939		)
Asset retirement obligation	(1,600		)
Property and equipment	1,818
Intangible assets	3,360
Bargain purchase gain	(3,473		)
Total consideration	$	6,500

Schedule of unaudited pro forma condensed combined statements

The following pro forma condensed combined information for the year ended December 31, 2014 is presented as if the acquisition of the CTRM Business had occurred on January 1, 2013.



	Year Ended December 31,
(in thousands)	2014
Pro forma revenue	$	44,906
Pro forma net loss	(30,115		)
Pro forma net loss per share - basic and diluted	(3.10		)

Selected Balance Sheet Components (Tables)

12 Months Ended

Dec. 31, 2016

Balance Sheet Related Disclosures [Abstract]

Schedule of inventory

Inventory as of December 31, 2016 and 2015:



(In thousands)	2016		2015
Raw materials	$	3,214	$	1,228
Work-in-process	257		131
Finished goods	17		20
Inventory	$	3,488	$	1,379

Schedule of property and equipment, net

Property and Equipment, net as of December 31, 2016 and 2015:



(In thousands)	2016			2015
Machinery and equipment	$	3,150		$	3,280
Furniture, fixtures and office equipment	931			931
Computer equipment and software	3,147			2,662
Leasehold improvements	3,332			2,393
Construction in process	408			421
	10,968			9,687
Less accumulated depreciation	(7,093		)	(5,638		)
Property and Equipment	$	3,875		$	4,049

Schedule of intangible assets, net

Intangible assets, net as of December 31, 2016 and 2015:



(In thousands)	2016		2015
Commercial rights	$	—	$	3,360
Less accumulated amortization	—		(443		)
Intangible assets	$	—	$	2,917

Schedule of accrued expenses

Accrued Expenses as of December 31, 2016 and 2015:



(In thousands)	2016		2015
Bonus	$	2,433	$	1,956
Employee related accruals	1,668		1,341
Accrued expenses	422		75
Other	—		231
Accrued expenses	$	4,523	$	3,603

Stock-Based Compensation (Tables)

12 Months Ended

Dec. 31, 2016

Disclosure of Compensation Related Costs, Share-based Payments [Abstract]

Schedule of weighted average assumptions used to estimate fair value of each service-based stock option grant



	Year Ended December 31,
Service-Based Stock Options	2016	2015	2014
Expected dividend rate	—%	—%	—%
Expected stock price volatility	78.7 – 92.2%	77.4 – 88.1%	82.4 – 88.2%
Risk-free interest rate	1.1 – 2.1%	1.5 – 2.0%	1.7 – 2.2%
Expected life (years)	5.5 – 6.3	5.5 – 6.3	5.5 – 6.3

Summary of activity for service-based stock options

The following table summarizes the activity for service-based stock options for the indicated periods:



Service-Based Stock Options	Options		Weighted Average Exercise Price		Weighted Average Remaining Contractual Term	Aggregate Intrinsic Value
Outstanding at December 31, 2014	477,530		$	21.74	8.0	$	—
Granted	2,216,600		$	3.11
Exercised	(3,566	)	$	3.02		$	1,000
Expired	(17,791	)	$	40.02
Forfeited	(149,373	)	$	3.35
Outstanding at December 31, 2015	2,523,400		$	36.43	8.7	$	5,000
Granted	1,110,530		$	3.01
Exercised	(39,231	)	$	3.06
Expired	(85,700	)	$	35.76
Forfeited	(153,307	)	$	3.61
Outstanding at December 31, 2016	3,355,692		$	4.66	8.2	$	610
Exercisable at December 31, 2016	1,339,675		$	6.99		$	106

Net Loss Per Common Share (Tables)

12 Months Ended

Dec. 31, 2016

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:



	Year Ended December 31,
(Amounts in thousands, except per share amounts)	2016			2015			2014
Numerator:
Net loss	$	(19,566	)	$	(16,340	)	$	(19,920	)
Less: earnings attributable to convertible preferred stock	7,579			6,736			6,005
Numerator of basic and diluted EPS	$	(27,145	)	$	(23,076	)	$	(25,925	)
Denominator:
Denominator for basic and diluted EPS: weighted-average common shares outstanding	23,093			23,760			11,642
Net loss per share attributable to common shareholders (basic and diluted)	$	(1.18	)	$	(0.97	)	$	(2.23	)

Stock Purchase Warrants (Tables)

12 Months Ended

Dec. 31, 2016

Warrants and Rights Note Disclosure [Abstract]

Schedule of warrants outstanding

The following table describes the outstanding warrants:



	August 2013 Warrants	September 2016 Warrants
Exercise price	$4.80	$2.48
Expiration date	August 16, 2018	September 9, 2022
Total shares issuable on exercise	724,950	117,074

Schedule of assumptions used in calculating estimated fair value of warrants

The assumptions used by the Company are summarized in the following table:



August 2013 Warrants	December 31, 2016			December 31, 2015
Closing stock price	$	3.00		$	2.58
Expected dividend yield	—		%	—		%
Expected stock price volatility	97.9		%	91.4		%
Risk-free interest rate	1.03		%	1.31		%
Expected life (years)	1.62			2.63



September 2016 Warrants	September 9, 2016
Closing stock price	$	2.20
Expected dividend rate	—		%
Expected stock price volatility	89.8		%
Risk-free interest rate	1.4		%
Expected life (years)	6.00

- Definition

Tabular disclosure of warrants or rights issued. Warrants and rights outstanding are derivative securities that give the holder the right to purchase securities (usually equity) from the issuer at a specific price within a certain time frame. Warrants are often included in a new debt issue to entice investors by a higher return potential. The main difference between warrants and call options is that warrants are issued and guaranteed by the company, whereas options are exchange instruments and are not issued by the company. Also, the lifetime of a warrant is often measured in years, while the lifetime of a typical option is measured in months. Disclose the title of issue of securities called for by warrants and rights outstanding, the aggregate amount of securities called for by warrants and rights outstanding, the date from which the warrants or rights are exercisable, and the price at which the warrant or right is exercisable.

+ References + Details

Fair Value Measurements (Tables)

12 Months Ended

Dec. 31, 2016

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:



	December 31, 2016								December 31, 2015
	Fair value measurement category								Fair value measurement category
(In thousands)	Total		Level 1		Level 2		Level 3		Total		Level 1		Level 2		Level 3
Liabilities:
Warrant liabilities	$	757	$	—	$	757	$	—	$	757	$	—	$	757	$	—

Summary of change in estimated fair values of warrant liabilities

The following table summarizes the change in the estimated fair value of the Company’s warrant liabilities:



Warrant Liabilities (In thousands)
Balance at December 31, 2014	$	1,081
Warrant exercises	—
Decrease in fair value	(324		)
Balance at December 31, 2015	757
Change in fair value	—
Balance at December 31, 2016	$	757

Income Taxes (Tables)

12 Months Ended

Dec. 31, 2016

Income Tax Disclosure [Abstract]

Summary of income (loss) before income taxes for U.S. and non-U.S. operations

Income (loss) before income taxes for U.S and non-U.S operations was as follows:



	Year Ended December 31,
	2016			2015			2014
U.S. loss	$	(19,302	)	$	(16,235	)	$	(18,078	)
Non U.S. loss	(264		)	(105		)	(1,842		)
	$	(19,566	)	$	(16,340	)	$	(19,920	)

Schedule of reconciliation of income taxes computed using the federal statutory rate to the taxes reported in consolidated statements of operations

A reconciliation of income taxes computed using the federal statutory rate to the taxes reported in the consolidated statements of operations is as follows:



	Year Ended December 31,
(In thousands)	2016			2015			2014
Loss before income taxes	$	(19,566	)	$	(16,340	)	$	(19,920	)
Federal statutory rate	34		%	34		%	34		%
Taxes computed at federal statutory rate	(6,652		)	(5,556		)	(6,773		)
State taxes (net of federal benefit)	(1,016		)	(392		)	(463		)
Warrants	—			(118		)	(10		)
Nondeductible stock compensation	549			543			48
State Rate Change	(614		)	—			—
Michigan NOL benefit	—			—			—
Net operating loss expirations	—			—			655
Write-off of Section 382 limited NOL’s	—			—			67,781
Write-off of Section 383 limited R&D credits	—			—			1,600
Other	56			57			352
Adjustment to prior year filed returns	—			(5,203		)	—
Change in valuation allowance	7,677			10,669			(63,190		)
Reported income taxes	$	—		$	—		$	—

Schedule of deferred tax assets

Deferred tax assets consist of the following:



	Year Ended December 31,
(In thousands)	2016			2015
Net operating loss carryforwards	$	10,343		$	13,998
Employee benefits and stock compensation	2,896			2,485
Research and development costs	13,659			4,903
Fixed assets	700			453
Intangible assets	—			(477		)
Inventory reserve	1,898			510
Other, net	196			143
Total deferred tax assets	29,692			22,015
Valuation allowance	(29,692		)	(22,015		)
Net deferred tax assets	$	—		$	—

Supplementary Quarterly Financial Information (unaudited) (Tables)

12 Months Ended

Dec. 31, 2016

Quarterly Financial Information Disclosure [Abstract]

Schedule of quarterly financial information



In thousands, except per share data)	First Quarter			Second Quarter			Third Quarter			Fourth Quarter			Year
2016
Revenues	$	14,108		$	12,823		$	10,929		$	16,523		$	54,383
Gross profit	7,548			5,523			4,073			8,932			26,076
Loss from operations	(1,992		)	(4,984		)	(6,380		)	(5,889		)	(19,245		)
Net loss	(3,650		)	(3,044		)	(6,675		)	(6,197		)	(19,566		)
Net loss per share (Basic and Diluted)	(0.24		)	(0.22		)	(0.38		)	(0.34		)	(1.18		)
2015
Revenues	$	10,849		$	13,590		$	11,309		$	15,420		$	51,168
Gross profit (loss)	5,281			6,689			4,537			8,191			24,698
Loss from operations	(4,572		)	(2,265		)	(4,877		)	(4,957		)	(16,671		)
Net loss	(4,862		)	(2,152		)	(4,416		)	(4,910		)	(16,340		)
Net loss per share (Basic and Diluted)	(0.27		)	(0.16		)	(0.26		)	(0.28		)	(0.97		)

Organization (Details) $ in Thousands	3 Months Ended								12 Months Ended
Organization (Details) $ in Thousands	Dec. 31, 2016 USD ($)	Sep. 30, 2016 USD ($)	Jun. 30, 2016 USD ($)	Mar. 31, 2016 USD ($)	Dec. 31, 2015 USD ($)	Sep. 30, 2015 USD ($)	Jun. 30, 2015 USD ($)	Mar. 31, 2015 USD ($)	Dec. 31, 2016 USD ($) segment	Dec. 31, 2015 USD ($)	Dec. 31, 2014 USD ($)	Nov. 30, 2016 USD ($)	May 30, 2014 patent	Dec. 31, 2013 USD ($)
Business Acquisition [Line Items]
Number of reportable segments \| segment									1
Accumulated deficit	$ (343,591)				$ (324,025)				$ (343,591)	$ (324,025)
Net loss	6,197	$ 6,675	$ 3,044	$ 3,650	4,910	$ 4,416	$ 2,152	$ 4,862	19,566	16,340	$ 19,920
Cash	22,978				$ 14,581				22,978	$ 14,581	$ 30,343			$ 8,059
CTRM Business
Business Acquisition [Line Items]
Number of patents and patents applications acquired (over) \| patent													250
December 31, 2016 \| Revolving credit facility \| SVB
Business Acquisition [Line Items]
Minimum revenue covenant	52,000								52,000			$ 56,000
December 31, 2017 \| Revolving credit facility \| SVB
Business Acquisition [Line Items]
Minimum revenue covenant	$ 60,000								$ 60,000

Summary of Significant Accounting Policies (Details)	12 Months Ended
Summary of Significant Accounting Policies (Details)	Dec. 31, 2016
Equipment and computers \| Minimum
Property, Plant and Equipment
Useful lives	3 years
Equipment and computers \| Maximum
Property, Plant and Equipment
Useful lives	5 years
Furniture and fixtures
Property, Plant and Equipment
Useful lives	5 years
Building improvements and leasehold improvements \| Maximum
Property, Plant and Equipment
Useful lives	7 years

Acquisitions (Details) $ in Thousands		12 Months Ended
Acquisitions (Details) $ in Thousands	May 30, 2014 USD ($) patent	Dec. 31, 2016 USD ($)	Dec. 31, 2015 USD ($)	Dec. 31, 2014 USD ($)
Total purchase price allocation
Bargain purchase gain		$ 0	$ 0	$ (3,473)
Restructuring charge		$ 100
CTRM Business
Business Acquisition [Line Items]
Number of patents and patents applications acquired (over) \| patent	250
Total purchase price consideration
Cash payment	$ 4,000
Promissory note	2,500
Total acquisition consideration	6,500
Total purchase price allocation
Accounts payable and accrued expenses	5,050
Accounts receivable	53
Inventory	2,039
Other current assets	192
Accounts payable and accrued expenses	(939)
Asset retirement obligation	(1,600)
Property and equipment	1,818
Intangible assets	3,360
Bargain purchase gain	(3,473)
Total consideration	6,500
Restructuring charge				$ 3,000
CTRM Business \| Sanofi \| Denmark
Total purchase price allocation
Cash received in order to fund the restructuring of the Denmark operations and close the facility	$ 5,000

Acquisitions - Pro forma Financial Information (Details) - CTRM Business $ / shares in Units, $ in Thousands	12 Months Ended
	Dec. 31, 2014 USD ($) $ / shares
Business Acquisition [Line Items]
Pro forma revenue	$ 44,906
Pro forma net income (loss)	$ (30,115)
Pro forma net income (loss) per share - basic and diluted (in dollars per share) \| $ / shares	$ (3.10)

Restructuring (Details)	12 Months Ended
Restructuring (Details)	Dec. 31, 2016 USD ($)	Dec. 31, 2014 USD ($)	Dec. 31, 2015 USD ($)	Jun. 30, 2014 position
Restructuring
Number of full time employee positions eliminated \| position				80
Percentage of full time employee positions eliminated				30.00%
Restructuring charge	$ 100,000
Restructuring reserve	0		$ 0
Asset retirement obligation	$ 200,000
Cost of product sales
Restructuring
Restructuring charge		$ 2,500,000
Selling, general and administrative expenses
Restructuring
Restructuring charge		500,000
CTRM Business
Restructuring
Restructuring charge		$ 3,000,000

Selected Balance Sheet Components (Details) - USD ($) $ in Thousands	Dec. 31, 2016	Dec. 31, 2015
Inventory:
Raw materials	$ 3,214	$ 1,228
Work-in-process	257	131
Finished goods	17	20
Inventory	$ 3,488	$ 1,379

Selected Balance Sheet Components - Property and Equipment (Details) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2016	Dec. 31, 2015	Dec. 31, 2014
Property and equipment, net:
Total property and equipment, gross	$ 10,968	$ 9,687
Accumulated depreciation	(7,093)	(5,638)
Property and Equipment	3,875	4,049
Depreciation expense	1,600	1,300	$ 800
Machinery and equipment
Property and equipment, net:
Total property and equipment, gross	3,150	3,280
Furniture, fixtures and office equipment
Property and equipment, net:
Total property and equipment, gross	931	931
Computer equipment and software
Property and equipment, net:
Total property and equipment, gross	3,147	2,662
Leasehold improvements
Property and equipment, net:
Total property and equipment, gross	3,332	2,393
Construction in process
Property and equipment, net:
Total property and equipment, gross	$ 408	$ 421

Selected Balance Sheet Components - Amortization Expense (Details) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2016	Dec. 31, 2015	Dec. 31, 2014
Intangible assets, net
Amortization expense	$ 300	$ 300	$ 200
Commercial rights
Intangible assets, net
Gross amount	0	3,360
Accumulated amortization	0	(443)
Intangible assets	$ 0	$ 2,917

Selected Balance Sheet Components - Accrued Expenses (Details) - USD ($) $ in Thousands	Dec. 31, 2016	Dec. 31, 2015
Accrued expenses
Bonus	$ 2,433	$ 1,956
Employee related accruals	1,668	1,341
Accrued expenses	422	75
Other	0	231
Accrued expenses	$ 4,523	$ 3,603

Debt (Details) - SVB	Mar. 08, 2016 USD ($) installment	Dec. 31, 2016 USD ($)	Nov. 30, 2016 USD ($)	Sep. 09, 2016 USD ($)
Debt Instrument [Line Items]
Weighted average interest rate		7.70%
Revolving credit facility \| December 31, 2016
Debt Instrument [Line Items]
Minimum revenue covenant		$ 52,000,000	$ 56,000,000
Revolving credit facility \| December 31, 2017
Debt Instrument [Line Items]
Minimum revenue covenant		60,000,000
Debt financing agreement
Debt Instrument [Line Items]
Debt instrument, face amount	$ 15,000,000.0
Maximum borrowing capacity (up to)				$ 20,000,000
Unamortized deferred financing costs, original issue costs		100,000
Unamortized deferred financing costs, lender fees		300,000
Debt financing agreement \| Revolving credit facility \| Line of credit
Debt Instrument [Line Items]
Revolving line of credit, borrowing capacity (up to)	$ 10,000,000
Line of credit, current		2,500,000
Remaining borrowing capacity		7,500,000
Term loan
Debt Instrument [Line Items]
Short-term bank loans and notes payable		$ 8,000,000
Term loan \| Prime Rate
Debt Instrument [Line Items]
Basis spread on variable rate	5.00%
Number of installments \| installment	36
Term loan \| Prime Rate \| Minimum
Debt Instrument [Line Items]
Basis spread on variable rate	1.25%
Term loan \| Debt Instrument, Redemption, Period One
Debt Instrument [Line Items]
Debt instrument, face amount	$ 4,000,000
Term loan \| Debt Instrument, Redemption, Period Two
Debt Instrument [Line Items]
Debt instrument, face amount	4,000,000
Term loan \| Debt Instrument, Redemption, Period Three
Debt Instrument [Line Items]
Debt instrument, face amount	$ 2,000,000

Stock-Based Compensation (Details) - USD ($) $ / shares in Units, $ in Thousands	1 Months Ended	12 Months Ended
	Jan. 31, 2017	Dec. 31, 2016	Dec. 31, 2015	Dec. 31, 2014	Oct. 01, 2015
Stock-Based Compensation
Shares issued under the Employee Stock Purchase Plan (in shares)		$ 467
2004, 2001 and 1992 PLANS
Stock-Based Compensation
Awards available for future grant under the Plan (in shares)		0
2009 Plan
Stock-Based Compensation
Awards available for future grant under the Plan (in shares)		1,090,645
Service-based stock options
Stock-Based Compensation
Vesting period		4 years
Stock-based compensation expense		$ 2,300	$ 2,700	$ 800
Weighted average grant-date fair value (in dollars per share)		$ 2.15	$ 2.22	$ 2.85
Weighted average assumptions used to estimate fair value of each service-based stock option grant
Expected dividend rate		0.00%	0.00%	0.00%
Options
Outstanding at the beginning of the period (in shares)	3,355,692	2,523,400	477,530
Granted (in shares)		1,110,530	2,216,600
Exercised (in shares)		(39,231)	(3,566)
Expired (in shares)		(85,700)	(17,791)
Forfeited (in shares)		(153,307)	(149,373)
Outstanding at the end of the period (in shares)		3,355,692	2,523,400	477,530
Exercisable at the end of the period (in shares)		1,339,675
Weighted Average Exercise Price
Outstanding at the beginning of the period (in dollars per share)	$ 4.66	$ 36.43	$ 21.74
Granted (in dollars per share)		3.01	3.11
Exercised (in dollars per share)		3.06	3.02
Expired (in dollars per share)		35.76	40.02
Forfeited or expired (in dollars per share)		3.61	3.35
Outstanding at the end of the period (in dollars per share)		4.66	$ 36.43	$ 21.74
Exercisable at the end of the period (in dollars per share)		$ 6.99
Weighted Average Remaining Contractual Term
Outstanding		8 years 2 months 12 days	8 years 8 months 12 days	8 years
Aggregate Intrinsic Value
Outstanding		$ 610	$ 5,000	$ 0
Exercised			1,000
Exercisable at end of period		106
Additional disclosures
Total unrecognized compensation cost		$ 2,400
Weighted average period over which unrecognized compensation is expected to be recognized		2 years 9 months
Total fair value of options vested		$ 2,200	$ 1,700	$ 1,500
Service-based stock options \| Minimum
Weighted average assumptions used to estimate fair value of each service-based stock option grant
Expected stock price volatility		78.70%	77.40%	82.40%
Risk-free interest rate		1.10%	1.50%	1.70%
Expected life		5 years 6 months	5 years	5 years 6 months
Service-based stock options \| Maximum
Stock-Based Compensation
Expiration period		10 years
Weighted average assumptions used to estimate fair value of each service-based stock option grant
Expected stock price volatility		92.20%	88.10%	88.20%
Risk-free interest rate		2.10%	2.00%	2.20%
Expected life		6 years 3 months 18 days	6 years 3 months 18 days	6 years 3 months 18 days
Service-based stock options \| Non-employee
Stock-Based Compensation
Expiration period		10 years
Vesting period		1 year
Options
Granted (in shares)		90,000
Service-based stock options \| 2009 Plan
Stock-Based Compensation
Vesting period		4 years
Employee stock
Stock-Based Compensation
Common stock available for issuance (in shares)					1,000,000
Stock-based compensation expense		$ 200
Employee stock \| Subsequent event
Stock-Based Compensation
Shares purchased during period (in shares)	34,392
Shares issued under the Employee Stock Purchase Plan (in shares)	$ 100

Shareholders' Equity (Details)								3 Months Ended	12 Months Ended
Shareholders' Equity (Details)	Dec. 21, 2016 USD ($) $ / shares shares	Nov. 22, 2016 shares	Oct. 10, 2016 USD ($)	Dec. 23, 2015 USD ($) shares	Dec. 18, 2015 shares	Jul. 09, 2014 USD ($) warrant_holder $ / shares shares	Jan. 21, 2014 USD ($) $ / shares shares	Dec. 31, 2016 USD ($) $ / shares shares	Dec. 31, 2016 USD ($) $ / shares shares	Dec. 31, 2014 shares	Sep. 09, 2016 $ / shares	Dec. 31, 2015 $ / shares shares	Aug. 31, 2013 $ / shares shares
Shareholders' Equity
Number of shares of common stock sold (in shares)								31,595,000	31,595,000			23,789,000
Proceeds from issuance of common stock \| $	$ 18,000,000
Number of common shares sold (in shares)	7,130,000
Offering price (in dollars per share) \| $ / shares	$ 2.75
Underwriter's discount \| $	$ 1,400,000
Issuance cost \| $	$ 200,000
Series A Convertible Preferred Stock
Shareholders' Equity
Shares issued upon conversion (in shares)				1,250	1,250
Common Stock
Shareholders' Equity
Number of common shares sold (in shares)									7,538,000	18,655,000
Shares converted (in shares)				1,250,000	1,250,000
Shares issued upon conversion (in shares)										408,000
Conversion of stock, amount converted \| $				$ 3,200,000
Preferred Stock
Shareholders' Equity
Shares converted (in shares)		1,250,000		1,250,000
Lincoln Park
Shareholders' Equity
Period over which shares of common stock to be purchased							30 months
Floor price for sale of shares of common stock (in dollars per share) (less than) \| $ / shares							$ 2.50
Number of shares of common stock sold (in shares)								985,499	985,499
Proceeds from issuance of common stock \| $									$ 3,900,000
Cowen and Company, LLC
Shareholders' Equity
At-the-market sales agreement, maximum aggregate proceeds \| $			$ 25,000,000.0
At-the-market-sales agreement, proceeds from issuance of common stock \| $								$ 800,000
Amount of net capacity remaining on the ATM \| $								$ 24,200,000	$ 24,200,000
Cowen and Company, LLC \| Common Stock
Shareholders' Equity
At-the-market sales agreement, shares issued (in shares)								357,856
Maximum \| Lincoln Park
Shareholders' Equity
Value of shares of common stock to be sold \| $							$ 15,000,000.0
Number of shares of common stock to be purchased in regular purchases							50,000
Number of shares of common stock to be purchased depending upon the closing sale price of the common stock (in shares)							100,000
Period of business days over which purchase price of shares of common stock will be determined							10 days
Threshold on percentage of outstanding shares of the common stock that can be beneficially owned by counterparty									9.99%
Maximum \| Cowen and Company, LLC
Shareholders' Equity
Percentage of gross proceeds payable as commission			3.00%
Minimum \| Lincoln Park
Shareholders' Equity
Threshold closing sale price of the common stock on the date of a regular purchase to trigger purchase of additional amounts as accelerated purchases (in dollars per share) (equals or exceeds) \| $ / shares							$ 3.00
August 2013 warrants
Shareholders' Equity
Number of warrant holders (in holders) \| warrant_holder						1
Number of shares purchased on exercise of warrants (in shares)						362,500							724,950
Exercise price of warrants (in dollars per share) \| $ / shares						$ 4.80							$ 4.80
Net proceeds from exercise of warrants \| $						$ 1,500,000
Offering price (in dollars per share) \| $ / shares								$ 3	$ 3		$ 2.20	$ 2.58

Preferred Stock (Details)		1 Months Ended		12 Months Ended
Preferred Stock (Details)	Aug. 15, 2011 right	Oct. 31, 2013 right	Mar. 31, 2012	Dec. 31, 2016 $ / shares shares
Shareholder Rights Plan
Number of rights for each outstanding share of common stock (in rights) \| right	1	20
Additional number of rights per common share (in rights) \| right	1
Number of rights deemed to be delivered for each share of common stock issued or transferred (in rights) \| right		20
Series A Junior Participating Cumulative Preferred Stock
Shareholder Rights Plan
Number of shares purchased on exercise of warrants (in shares)				0.0001
Exercise price per share (in dollars per share) \| $ / shares				$ 30.00
Preferred stock, shares authorized (in shares)				45,000
Preferred stock, shares issued (in shares)				0
Convertible preferred stock, shares outstanding (in shares)				0
Multiple of the value of common stock acquired (after conversion from preferred) to the exercise price of stock purchase right in the event of an acquiring person event				2
Multiple of the value of common stock acquired to the exercise price of stock purchase right in the event of a merger of the entity				2
Redemption price per right (in dollars per right) \| $ / shares				$ 0.001
Minimum \| Series A Junior Participating Cumulative Preferred Stock
Shareholder Rights Plan
Percentage of common stock to be acquired for rights to be exercisable by an individual or group				15.00%
Percentage of common stock to be owned for rights to be exercisable by an individual or group commencing a tender offer				15.00%
Eastern Capital Limited and its affiliates \| Maximum
Shareholder Rights Plan
Percentage of common stock approved to be purchased			49.90%

Preferred Stock - Series B Convertible Preferred Stock (Details) - USD ($) $ / shares in Units, $ in Millions				12 Months Ended
	Dec. 21, 2016	Aug. 12, 2013	Mar. 09, 2012	Dec. 31, 2016
Series B Convertible Preferred Stock
Number of common shares sold (in shares)	7,130,000
Percentage of cumulative dividend rate				11.50%
Series B voting convertible preferred stock
Series B Convertible Preferred Stock
Period of closing of offering after which shares are convertible				5 years
Conversion price per share (in dollars per share)				$ 3.25
Conversion ratio, the number of shares of common stock received per share of convertible preferred stock				50
Reclassification of Series B preferred stock into shareholders' equity		$ 38.4
Series B-1 non-voting convertible preferred stock
Series B Convertible Preferred Stock
Number of common shares sold (in shares)			12,308
Offering price per share (in dollars per share)			$ 3,250
Period of closing of offering after which shares are convertible		5 years
Accumulated shares but undeclared dividends (in shares)				455,308
Redemption price (in dollars per share)		$ 7,430

Preferred Stock Preferred Stock - Series A Convertible Preferred Stock (Details) - shares				12 Months Ended
	Nov. 22, 2016	Dec. 23, 2015	Dec. 18, 2015	Dec. 31, 2014
Series A Convertible Preferred Stock
Shareholders' Equity
Shares issued upon conversion (in shares)		1,250	1,250
Common Stock
Shareholders' Equity
Shares converted (in shares)		1,250,000	1,250,000
Shares issued upon conversion (in shares)				408,000
Convertible preferred stock, shares issued upon conversion (in shares)			1,000
Preferred Stock
Shareholders' Equity
Shares converted (in shares)	1,250,000	1,250,000

Net Loss Per Common Share (Details) - USD ($) $ / shares in Units, shares in Thousands, $ in Thousands	3 Months Ended								12 Months Ended
	Dec. 31, 2016	Sep. 30, 2016	Jun. 30, 2016	Mar. 31, 2016	Dec. 31, 2015	Sep. 30, 2015	Jun. 30, 2015	Mar. 31, 2015	Dec. 31, 2016	Dec. 31, 2015	Dec. 31, 2014
Numerator:
Net loss	$ (6,197)	$ (6,675)	$ (3,044)	$ (3,650)	$ (4,910)	$ (4,416)	$ (2,152)	$ (4,862)	$ (19,566)	$ (16,340)	$ (19,920)
Less: earnings attributable to convertible preferred stock									7,579	6,736	6,005
Numerator of basic and diluted EPS									$ (27,145)	$ (23,076)	$ (25,925)
Denominator for basic and diluted EPS:
Weighted-average common shares outstanding (in shares)									23,093	23,760	11,642
Net loss per share attributable to common shareholders (basic and diluted) (in dollars per share)	$ (0.34)	$ (0.38)	$ (0.22)	$ (0.24)	$ (0.28)	$ (0.26)	$ (0.16)	$ (0.27)	$ (1.18)	$ (0.97)	$ (2.23)
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)									5,300	6,700	2,300

Stock Purchase Warrants (Details)		12 Months Ended
Stock Purchase Warrants (Details)	Sep. 09, 2016 holder $ / shares shares	Dec. 31, 2016 $ / shares	Dec. 31, 2015 $ / shares	Dec. 21, 2016 $ / shares	Sep. 30, 2016 $ / shares shares	Jul. 09, 2014 $ / shares shares	Aug. 31, 2013 $ / shares shares
Assumptions used in calculating the estimated fair value of the warrants
Closing stock price (in dollars per share)				$ 2.75
August 2013 warrants
Stock Purchase Warrants
Exercise price per share (in dollars per share)						$ 4.80	$ 4.80
Total shares issuable on exercise (in shares) \| shares						362,500	724,950
Assumptions used in calculating the estimated fair value of the warrants
Closing stock price (in dollars per share)	$ 2.20	$ 3	$ 2.58
Expected dividend rate	0.00%	0.00%	0.00%
Expected stock price volatility	89.80%	97.90%	91.40%
Risk-free interest rate	1.40%	1.03%	1.31%
Expected life	6 years	1 year 7 months 12 days	2 years 7 months 17 days
September 2022 Warrants
Stock Purchase Warrants
Exercise price per share (in dollars per share)					$ 2.48
Total shares issuable on exercise (in shares) \| shares					117,074
September 2016 Warrants
Stock Purchase Warrants
Warrants issued (in shares) \| shares	117,074
Number of holders (in holders) \| holder	2

Fair Value Measurements (Details) - USD ($) $ in Thousands	12 Months Ended
Fair Value Measurements (Details) - USD ($) $ in Thousands	Dec. 31, 2016	Dec. 31, 2015	Dec. 31, 2014
Liabilities that are measured at fair value on a recurring basis
Warrant liabilities	$ 757	$ 757
Change in the estimated fair value of warrant liabilities
Balance at the beginning of the period	757
Increase (decrease) in fair value	0	(324)	$ 27
Balance at the end of the period	757	757
Recurring
Liabilities that are measured at fair value on a recurring basis
Warrant liabilities	757	1,081	1,081
Change in the estimated fair value of warrant liabilities
Balance at the beginning of the period	757	1,081
Warrant exercise		0
Increase (decrease) in fair value	0	(324)
Balance at the end of the period	757	757	$ 1,081
Recurring \| Level 2
Liabilities that are measured at fair value on a recurring basis
Warrant liabilities	757	757
Change in the estimated fair value of warrant liabilities
Balance at the beginning of the period	757
Balance at the end of the period	757	757
Recurring \| Level 3
Liabilities that are measured at fair value on a recurring basis
Warrant liabilities	0	0
Change in the estimated fair value of warrant liabilities
Balance at the beginning of the period	0
Balance at the end of the period	$ 0	$ 0

Income Taxes - Components of Income (Loss) Before Taxes (Details) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2016	Dec. 31, 2015	Dec. 31, 2014
Operating Loss Carryforwards [Line Items]
Loss before income taxes	$ (19,566)	$ (16,340)	$ (19,920)
U.S.
Operating Loss Carryforwards [Line Items]
Loss before income taxes	(19,302)	(16,235)	(18,078)
Non U.S.
Operating Loss Carryforwards [Line Items]
Loss before income taxes	$ (264)	$ (105)	$ (1,842)

Income Taxes - Deferred Tax Assets (Details) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2016	Dec. 31, 2015	Dec. 31, 2014
Reconciliation of income taxes computed using the federal statutory rate to the taxes reported in consolidated statements of operations
Loss before income taxes	$ 19,566	$ 16,340	$ 19,920
Federal statutory rate	34.00%	34.00%	34.00%
Taxes computed at federal statutory rate	$ (6,652)	$ (5,556)	$ (6,773)
State taxes (net of federal benefit)	(1,016)	(392)	(463)
Warrants	0	(118)	(10)
Nondeductible stock compensation	549	543	48
State Rate Change	(614)	0	0
Michigan NOL benefit	0	0	0
Net operating loss expirations	0	0	655
Write-off of Section 382 limited NOL’s	0	0	67,781
Write-off of Section 383 limited R&D credits	0	0	1,600
Other	56	57	352
Adjustment to prior year filed returns	0	(5,203)	0
Change in valuation allowance	7,677	10,669	(63,190)
Reported income taxes	0	0	$ 0
Deferred tax assets
Net operating loss carryforwards	10,343	13,998
Employee benefits and stock compensation	2,896	2,485
Research and development costs	13,659	4,903
Fixed assets	700	453
Intangible assets	0	(477)
Inventory reserve	1,898	510
Other, net	196	143
Total deferred tax assets	29,692	22,015
Valuation allowance	(29,692)	(22,015)
Net deferred tax assets	$ 0	$ 0

Income Taxes - Narrative (Details) - USD ($) $ in Millions		12 Months Ended
Income Taxes - Narrative (Details) - USD ($) $ in Millions	Sep. 17, 2014	Dec. 31, 2016	Dec. 31, 2015	Sep. 16, 2014
Income Tax Disclosure [Abstract]
Rolling period over which cumulative change of ownership is required for change in control	3 years
Operating Loss Carryforwards [Line Items]
Projected annual limitation on the use of the net operating losses that existed prior to September 17, 2014				$ 0.8
Increase in valuation allowance		$ 7.7	$ 10.7
Federal \| Internal Revenue Service
Operating Loss Carryforwards [Line Items]
Net operating loss carryforwards		28.6
State
Operating Loss Carryforwards [Line Items]
Net operating loss carryforwards		$ 11.5

Concentration of Credit (Details) - Customer concentration - customer	12 Months Ended
	Dec. 31, 2016	Dec. 31, 2015
Revenue \| One distributor in the U.S
CONCENTRATION
Concentration risk, Number of customers	1	1
Concentration risk	31.00%	66.00%
Revenue \| One customer
CONCENTRATION
Concentration risk	11.00%	12.00%
Accounts receivable \| One distributor in the U.S
CONCENTRATION
Concentration risk	1.00%	76.00%
Accounts receivable \| One customer
CONCENTRATION
Concentration risk	5.00%	8.00%

Commitments and Contingencies - Narrative (Details) - USD ($)	1 Months Ended		12 Months Ended
	Oct. 31, 2015	Dec. 31, 2002	Dec. 31, 2016	Dec. 31, 2015	Dec. 31, 2014	Mar. 31, 2016
Licenses, Royalties and Collaborative Agreements and Commitments
Purchase obligation, due in second year	$ 600,000		$ 2,268,000
Purchase obligation, renewal option, term	5 years
Purchase obligation, automatic renewal, term	5 years
Landlord contributions toward tenant improvements						$ 2,000,000
Tenant improvements			900,000
Rent expense			$ 4,800,000	$ 4,900,000	$ 2,500,000
Corning
Licenses, Royalties and Collaborative Agreements and Commitments
Royalty revenue as a percentage of net sales of products		5.00%
Corning \| Maximum
Licenses, Royalties and Collaborative Agreements and Commitments
Future royalty revenue		$ 50,000,000

Commitments and Contingencies - Future Minimum Payments (Details) - USD ($) $ in Thousands	Dec. 31, 2016	Oct. 31, 2015
Operating leases
Total	$ 23,835
2017	5,138
2018	4,658
2019	4,319
2020	4,413
2021	4,546
More than 5 Years	761
Purchase commitments
Total	7,770
2017	2,268
2018	2,268	$ 600
2019	1,434
2020	600
2021	600
More than 5 Years	600
Capital leases
Total	75
2017	43
2018	32
2019
2020
2021
More than 5 years
Operating and capital leases and purchase commitments
Total operating and capital leases and purchase commitments	31,680
2017	7,449
2018	6,958
2019	5,753
2020	5,013
2021	5,146
More than 5 Years	$ 1,361

Subsequent Events (Details) - Subsequent event - shares	Mar. 09, 2017	Feb. 10, 2017	Mar. 10, 2017
Subsequent Event [Line Items]
Shares issued upon conversion (in shares)	0
Preferred Class A and Class B
Subsequent Event [Line Items]
Shares converted (in shares)		12,308
Accumulated shares but undeclared dividends (in shares)			9,570
Common Stock
Subsequent Event [Line Items]
Shares issued upon conversion (in shares)		1,093,892

Supplementary Quarterly Financial Information (unaudited) (Details) - USD ($) $ / shares in Units, $ in Thousands	3 Months Ended								12 Months Ended
	Dec. 31, 2016	Sep. 30, 2016	Jun. 30, 2016	Mar. 31, 2016	Dec. 31, 2015	Sep. 30, 2015	Jun. 30, 2015	Mar. 31, 2015	Dec. 31, 2016	Dec. 31, 2015	Dec. 31, 2014
Quarterly Financial Information Disclosure [Abstract]
Revenues	$ 16,523	$ 10,929	$ 12,823	$ 14,108	$ 15,420	$ 11,309	$ 13,590	$ 10,849	$ 54,383	$ 51,168
Gross profit (loss)	8,932	4,073	5,523	7,548	8,191	4,537	6,689	5,281	26,076	24,698	$ 11,503
Loss from operations	(5,889)	(6,380)	(4,984)	(1,992)	(4,957)	(4,877)	(2,265)	(4,572)	(19,245)	(16,671)	(23,534)
Net loss	$ (6,197)	$ (6,675)	$ (3,044)	$ (3,650)	$ (4,910)	$ (4,416)	$ (2,152)	$ (4,862)	$ (19,566)	$ (16,340)	$ (19,920)
Net loss per share (basic and diluted) (in dollars per share)	$ (0.34)	$ (0.38)	$ (0.22)	$ (0.24)	$ (0.28)	$ (0.26)	$ (0.16)	$ (0.27)	$ (1.18)	$ (0.97)	$ (2.23)

CONSOLIDATED STATEMENTS OF SHAREHOLDERS' EQUITY (Parenthetical) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2016	Dec. 31, 2014
Statement of Stockholders' Equity [Abstract]
Issuance of stock, issuance cost	$ 1,653	$ 3,167

Summary of Significant Accounting Policies - Undeclared Dividends (Details) $ in Millions	Dec. 31, 2016 USD ($)
Series B voting convertible preferred stock
Net Loss Per Share Attributable to Common Shareholders
Accumulated undeclared dividends	$ 6.7

Employee Savings Plan (Details) - USD ($) $ in Millions	12 Months Ended
Employee Savings Plan (Details) - USD ($) $ in Millions	Dec. 31, 2016	Dec. 31, 2015	Dec. 31, 2014
Compensation and Retirement Disclosure [Abstract]
Contributions made under 401(k) savings plan	$ 0.6	$ 0.5	$ 0.3