Corindus Vascular Robotics (CVRS) 10-K 11 Mar 16 2015 FY Annual report Financial data

Document and Entity Information

Document and Entity Information - USD ($)	12 Months Ended
	Dec. 31, 2015	Feb. 29, 2016	Jun. 30, 2015
Document And Entity Information [Abstract]
Entity Central Index Key	1,528,557
Entity Registrant Name	Corindus Vascular Robotics, Inc.
Document Type	10-K
Amendment Flag	false
Document Period End Date	Dec. 31, 2015
Trading Symbol	CVRS
Current Fiscal Year End Date	--12-31
Entity Well-known Seasoned Issuer	No
Entity Current Reporting Status	Yes
Entity Voluntary Filers	No
Entity Filer Category	Smaller Reporting Accelerated Filer
Entity Common Stock, Shares Outstanding		118,934,152
Entity Public Float			$ 172,001,000
Document Fiscal Period Focus	FY
Document Fiscal Year Focus	2,015

Consolidated Balance Sheets

Consolidated Balance Sheets - USD ($) $ in Thousands	Dec. 31, 2015	Dec. 31, 2014
Current Assets:
Cash and cash equivalents	$ 22,142	$ 28,526
Marketable securities	20,524
Accounts receivable	878	473
Inventories, net	1,329	1,519
Prepaid expenses and other current assets	591	574
Total current assets	45,464	31,092
Property and equipment, net	1,382	1,284
Deposits and other assets	$ 166	222
Deferred inventory costs		102
Notes receivable due from stockholders	$ 136	136
Total assets	47,148	32,836
Current liabilities:
Accounts payable	1,538	2,005
Accrued expenses	1,199	1,137
Deferred revenue	701	202
Current portion of long-term debt	4,038	1,517
Total current liabilities	7,476	4,861
Long-term liabilities:
Deferred revenue, net of current portion	106	531
Other liabilities	42	68
Long-term debt, net of current portion	3,677	7,594
Total long-term liabilities	3,825	8,193
Total liabilities	11,301	$ 13,054
Commitments and Contingencies (Note 12)
Stockholders' equity:
Preferred stock, $0.0001 par value; 10,000,000 shares authorized; none issued and outstanding
Common stock, $0.0001 par value; 250,000,000 shares authorized; 105,883,157 shares at December 31, 2014 and 118,832,441 shares at December 31, 2015 issued and outstanding	12	$ 11
Additional paid-in capital	149,489	104,648
Accumulated other comprehensive loss	(14)
Accumulated deficit	(113,640)	(84,877)
Total stockholders' equity	35,847	19,782
Total liabilities and stockholders' equity	$ 47,148	$ 32,836

Consolidated Balance Sheets (Pa

Consolidated Balance Sheets (Parenthetical) - $ / shares	Dec. 31, 2015	Dec. 31, 2014
Statement of Financial Position [Abstract]
Preferred stock, par value	$ 0.0001	$ 0.0001
Preferred stock, authorized shares	10,000,000	10,000,000
Preferred stock, issued shares	0	0
Preferred stock, outstanding shares	0	0
Common stock, par value	$ 0.0001	$ 0.0001
Common stock, authorized shares	250,000,000	250,000,000
Common stock, issued shares	118,832,441	105,883,157
Common stock, outstanding shares	118,832,441	105,883,157

Consolidated Statements of Oper

Consolidated Statements of Operations and Comprehensive Loss - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2015	Dec. 31, 2014	Dec. 31, 2013
Income Statement [Abstract]
Revenue	$ 2,729	$ 2,983	$ 896
Cost of revenue	3,724	4,904	2,430
Gross loss	(995)	(1,921)	(1,534)
Operating expenses:
Research and development	10,033	6,607	4,793
Selling, general and administrative	$ 16,143	13,002	$ 8,221
Restructuring charge		175
Total operating expenses	$ 26,176	19,784	$ 13,014
Operating loss	$ (27,171)	(21,705)	(14,548)
Other income (expense):
Warrant revaluation		(2,421)	(171)
Interest and other income (expense)	$ (1,592)	(415)	28
Total other expense, net	(1,592)	(2,836)	(143)
Net loss	$ (28,763)	$ (24,541)	$ (14,691)
Net loss per share-basic and diluted	$ (0.25)	$ (0.29)	$ (0.20)
Weighted-average common shares used in computing net loss per share-basic and diluted	113,254,925	84,990,198	73,360,259
Other comprehensive loss:
Net loss	$ (28,763)	$ (24,541)	$ (14,691)
Unrealized loss on marketable securities	(14)
Comprehensive loss	$ (28,777)	$ (24,541)	$ (14,691)

Consolidated Statement of Stock

Consolidated Statement of Stockholders' Equity - USD ($) $ in Thousands	Common Stock [Member]	Additional Paid-in Capital [Member]	Accumulated Other Comprehensive Loss [Member]	Accumnulated Deficit [Member]	Total
Beginning balance at Dec. 31, 2012	$ 7	$ 70,050		$ (45,645)	$ 24,412
Beginning balance, shares at Dec. 31, 2012	73,360,162
Issuance costs related to common stock		(10)			(10)
Stock-based compensation expense		329			329
Issuance of common stock upon exercise of stock options, shares	125
Net loss				(14,691)	(14,691)
Ending balance at Dec. 31, 2013	$ 7	70,369		(60,336)	10,040
Ending balance, shares at Dec. 31, 2013	73,360,287
Stock-based compensation expense		377			377
Reclassification of warrant liability		5,803			5,803
Issuance of common stock in connection with reverse acquisition	$ 2	(5)			(3)
Issuance of common stock in connection with reverse acquisition, shares	20,856,300
Issuance of common stock to private investor		2,000			2,000
Issuance of common stock to private investor, shares	1,000,000
Issuance of common stock	$ 2	25,485			25,487
Issuance of common stock, shares	10,666,570
Issuance of warrants to purchase common stock		619			619
Net loss				(24,541)	(24,541)
Ending balance at Dec. 31, 2014	$ 11	104,648		(84,877)	19,782
Ending balance, shares at Dec. 31, 2014	105,883,157
Stock-based compensation expense		505			505
Issuance of common stock	$ 1	44,391			44,392
Issuance of common stock, shares	12,650,000
Issuance of common stock upon exercise of stock options		76			76
Issuance of common stock upon exercise of stock options, shares	340,345
Common stock withheld to pay statutory minimum withholding taxes on exercise of stock options		(131)			(131)
Common stock withheld to pay statutory minimum withholding taxes on exercise of stock options, shares	(41,061)
Change in fair value of marketable securities			$ (14)		(14)
Net loss				(28,763)	(28,763)
Ending balance at Dec. 31, 2015	$ 12	$ 149,489	$ (14)	$ (113,640)	$ 35,847
Ending balance, shares at Dec. 31, 2015	118,832,441

Consolidated Statement of Stoc6

Consolidated Statement of Stockholders' Equity (Parenthetical) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2015	Dec. 31, 2014
Statement of Stockholders' Equity [Abstract]
Common stock issuance costs	$ 794	$ 1,179

Consolidated Statements of Cash

Consolidated Statements of Cash Flows - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2015	Dec. 31, 2014	Dec. 31, 2013
Operating activities
Net loss	$ (28,763)	$ (24,541)	$ (14,691)
Adjustments to reconcile net loss to net cash flows used in operating activities:
Depreciation and amortization	706	622	607
Stock-based compensation expense	$ 505	377	$ 329
Write down of inventories		341
Accretion of interest expense	$ 625	$ 106
Accretion on available-for-sale securities	$ (13)
Warrant revaluation		$ 2,421	$ 171
Changes in operating assets and liabilities:
Accounts receivable	$ (404)	(438)	(23)
Due from related party		125	130
Prepaid expenses and other current assets	$ (17)	(80)	$ 134
Deferred inventory costs	102	(102)
Inventories	(346)	257	$ (2,313)
Deposits and other assets	56	24	89
Accounts payable, accrued expenses and other liabilities	(380)	1,584	329
Deferred revenue	73	733	(65)
Net cash used in operating activities	(27,856)	$ (18,571)	$ (15,303)
Investing activities
Purchases of available-for-sale securities	(22,766)
Maturities of available-for-sale securities	2,241
Purchases of property and equipment	(268)	$ (122)	$ (378)
Net cash used in investing activities	(20,793)	(122)	(378)
Financing activities
Proceeds from issuance of common stock, net of offering costs	44,392	27,487	$ (10)
Proceeds from issuance of long term debt and warrants, net of deferred financing costs and discount	(50)	$ 9,890
Proceeds from exercise of stock options	76
Payments of statutory minimum withholding taxes on stock option exercises	(131)
Payments on long term debt	$ (2,022)
Other		$ (3)
Net cash provided by (used in) financing activities	$ 42,265	37,374	$ (10)
Net increase (decease) in cash and cash equivalents	(6,384)	18,681	(15,691)
Cash and cash equivalents at beginning of period	28,526	9,845	25,536
Cash and cash equivalents at end of period	22,142	28,526	9,845
Supplemental Disclosure of Cash Flow Information:
Transfer from inventories to property and equipment in the field	587	347	$ 588
Reclassification of warrant liability to stockholders' equity		5,803
Deferred public offering costs in accounts payable and accrued expenses		50
Supplemental Cash Flow Information
Interest paid	$ 976	$ 266

Nature of Operations

Nature of Operations	12 Months Ended
	Dec. 31, 2015
Organization, Consolidation and Presentation of Financial Statements [Abstract]
Nature of Operations	1. Nature of Operations The Company Corindus Vascular Robotics, Inc. (the “Company”), a Nevada corporation (formerly named Your Internet Defender, Inc. (“YIDI”)), acquired Corindus, Inc., a privately-held company, in a reverse acquisition on August 12, 2014. The Company’s corporate headquarters and research and development facility are in Waltham, Massachusetts and the Company is engaged in the marketing, sales and development of robotic-assisted catheterization systems (“CorPath System”). Since its inception on March 21, 2002, the Company has devoted its efforts principally to research and development, business development activities and raising capital. In July 2012, the Company received clearance from the FDA to market its CorPath System in the United States and shipped its first commercial product under this clearance in September 2012. In 2013, the Company moved into the growth stage, investing in sales and marketing in order to build the customer base. While the Company is initially cleared for and is targeting PCI procedures, the Company believes its technology platform has the capability to be developed in the future for other segments of the vascular market, including peripheral vascular, neurointerventional and other more complex cardiac interventions such as structural heart. In October 2015, the Company announced that the FDA had given 510(k) clearance for its robotic-assisted CorPath System to be used during percutaneous coronary interventions performed via radial access. The 510(k) clearance was based on results of a clinical trial conducted at Spectrum Health, Grand Rapids, Michigan, and St. Joseph’s Hospital Health Center, Syracuse, New York. The Company’s future capital requirements will depend upon many factors, including progress with developing, manufacturing and marketing its technologies, the time and costs involved in preparing, filing, prosecuting, maintaining and enforcing patent claims and other proprietary rights, its ability to establish collaborative arrangements, marketing activities and competing technological and market developments, including regulatory changes affecting medical procedure reimbursement, and overall economic conditions in its target markets. Recent Equity Offerings On May 28, 2015, the Company completed a public offering by issuing 12,650,000 shares of its common stock at $3.80 per share in exchange for proceeds of $44,392, net of underwriting discounts, commissions and other offering costs. In connection with the public offering, the Company’s common stock was approved for listing on the NYSE MKT, where it commenced trading on May 29, 2015 under the symbol “CVRS”. Liquidity The Company has incurred losses since inception and has funded its operations primarily through the issuance of capital stock and debt. As of December 31, 2015, the Company had an accumulated deficit of $113,640, and net borrowings outstanding of $7,978, of which $4,373 is contractually due over the next 12 months. The Company has cash, cash equivalents and marketable securities of $42,666 and working capital of $37,988 at December 31, 2015. The Company believes that these available resources will be sufficient to meet the Company’s cash requirements through December 31, 2016, including funding its anticipated losses and scheduled debt maturities. Additionally, the Company is in compliance with its debt covenant requirements as of December 31, 2015 and expects to remain in compliance throughout 2016. As the Company continues to incur losses, transition to profitability is dependent upon achieving a level of revenues adequate to support the Company’s cost structure. The Company may never achieve profitability, and unless and until doing so, intends to fund future operations through additional debt or equity offerings. There can be no assurances, however, that additional funding will be available on terms acceptable to the Company, if at all.

Significant Accounting Policies

Significant Accounting Policies	12 Months Ended
	Dec. 31, 2015
Accounting Policies [Abstract]
Significant Accounting Policies	2. Significant Accounting Policies Principles of Consolidation The consolidated financial statements include the accounts of the Company and its wholly owned subsidiaries, Corindus, Inc. and Corindus Security Corporation, which was created on December 21, 2012 to hold and invest the proceeds from issuance of equity. All intercompany transactions and balances have been eliminated in consolidation. The functional currency of both wholly-owned subsidiaries is the U.S. dollar and, therefore, the Company has not recorded any currency translation adjustments. In the fourth quarter of 2014, the Company participated in the formation of a not-for-profit, which was established to generate awareness of the health risks linked to the use of fluoroscopy in hospital catheterization. As of December 31, 2015, the Company’s Chief Executive Officer and one of its senior executives represented two of the three voting members of the board of directors of the entity. As a result, under the voting model used for the consolidation of related parties, which are controlled by a company, the Company has consolidated the financial statements of the entity, and recognized expenses of $18 and $386 for the years ended December 31, 2014 and 2015, respectively. The entity had assets and liabilities of $56 and $75, respectively, on the Company's balance sheet at December 31, 2015. The entity did not have any assets or liabilities on the Company's balance sheet at December 31, 2014. Segment Information The Company operates in one business segment, which is the development, marketing and sales of robotic-assisted vascular interventions. Operating segments are identified as components of an enterprise about which separate discrete financial information is available for evaluation by the chief operating decision maker in making decisions regarding resource allocation and assessing performance. To date, the chief operating decision maker has made such decisions and assessed performance at the company level, as one segment. The Company’s chief operating decision maker is the Chief Executive Officer. Revenues from domestic customers were $896, $2,068 and $2,684 for the years ending December 31, 2013, 2014 and 2015, respectively. Revenues from international customers, primarily in Dubai and Israel, were $0, $915 and $45 for the years ending December 31, 2013, 2014 and 2015, respectively. Use of Estimates The process of preparing financial statements in conformity with accounting principles generally accepted in the United States (“U.S. GAAP”) requires management to make estimates and assumptions that affect the reported amounts of assets and liabilities and disclosure of assets and liabilities at the date of the financial statements. Such management estimates include those relating to revenue recognition, inventory valuation, assumptions used in the valuation of stock-based awards, and valuation allowances against deferred income tax assets. Actual results could differ from those estimates. Cash Equivalents The Company considers highly liquid short-term investments, which consists of money market funds and certificates of deposit with original maturity dates of three months or less at the date of purchase, to be cash equivalents. From time to time, the Company’s cash balances may exceed federal deposit insurance limits. Marketable Securities The Company determines the appropriate classification of marketable securities at the time of purchase and reevaluates such designation at each balance sheet date. The Company has classified all of its marketable securities at December 31, 2015 as “available-for-sale” pursuant to ASC 320, Investments – Debt and Equity Securities. The Company records available-for-sale securities at fair value, with the unrealized gains and losses included in accumulated other comprehensive loss in stockholders’ equity. The Company adjusts the cost of available-for-sale debt securities for amortization of premiums and accretion of discounts to maturity. The Company includes such amortization and accretion in interest and other income (expense). The cost of securities sold is based on the specific identification method. The Company includes interest income on securities classified as available-for-sale in interest and other income (expense). The Company reviews marketable securities for other-than-temporary impairment whenever the fair value of a marketable security is less than the amortized cost and evidence indicates that a marketable security’s carrying amount is not recoverable within a reasonable period of time. Other-than-temporary impairments of investments are recognized in the consolidated statements of operations if the Company has experienced a credit loss, has the intent to sell the marketable security, or if it is more likely than not that the Company will be required to sell the marketable security before recovery of the amortized cost basis. At December 31, 2015, the balance in the Company’s accumulated other comprehensive loss was composed solely of activity related to the Company’s available-for-sale securities. There were no realized gains or losses recognized on the maturity of available-for-sale securities during the year ended December 31, 2015, and as a result, the Company did not reclassify any amount out of accumulated other comprehensive loss during that same period. The aggregate fair value of securities held by the Company in an unrealized loss position for less than twelve months as of December 31, 2015 consists of 13 certificates of deposit and two U.S. Treasuries. The Company has the intent and ability to hold such securities until recovery. As of December 31, 2015, the Company's available-for-sale securities had remaining maturities no greater than one year. The Company determined that there was no material change in the credit risk of the above investments. As a result, the Company determined it did not hold any investments with an other-than-temporary impairment as of December 31, 2015. The following table summarizes available-for-sale securities held at December 31, 2015: Description Amortized Cost Unrealized Gain Unrealized Loss Fair Value December 31, 2015 U.S. government treasuries $ 15,885 $ 1 $ (10 ) $ 15,876 Certificates of deposit 4,653 — (5 ) 4,648 Total $ 20,538 $ 1 $ (15 ) $ 20,524 Certain short-term securities with original maturities of less than 90 days are included in cash and cash equivalents on the consolidated balance sheet at December 31, 2015 and are not included in the table above. The Company did not hold any available-for-sale securities at December 31, 2014. Fair Value Measurements In accordance with ASC 820, Fair Value Measurements and Disclosures, the Company generally defines fair value as the price that would be received to sell an asset or paid to transfer a liability in an orderly transaction between market participants at the measurement date (exit price). The Company uses a three-tier fair value hierarchy, which classifies the inputs used in measuring fair values. The hierarchy gives the highest priority to unadjusted quoted prices in active markets for identical assets or liabilities (Level 1 measurements), and the lowest priority to unobservable inputs (Level 3 measurements). The three levels of the fair value hierarchy are described below: ● Level 1 – ● Level 2 – ● Level 3 – The following table sets forth the Company’s assets that are measured at fair value on a recurring basis as of December 31, 2015: Fair value measurement category Description Total Quoted prices in active markets Significant other observable inputs Significant unobservable inputs December 31, 2015: Assets: Cash equivalents $ 6,356 $ 6,107 $ 249 $ — Marketable securities: U.S. government treasuries 15,876 15,876 — — Certificates of deposit 4,648 — 4,648 — Total assets $ 26,880 $ 21,983 $ 4,897 $ — The Company’s financial instruments of deposits and notes receivable are carried at cost and approximate their fair values given the liquid nature of such items. The fair value of the Company’s long-term debt amounted to $9,111 and $7,715 at December 31, 2014 and 2015, respectively, based on discounted cash flow analysis, which included Level 3 inputs and fair value approximates recorded amounts. Concentrations of Credit Risk and Significant Customers The Company had the following customers that accounted for greater than 10% of its revenues for the year ended December 31, 2014 and 2015, respectively: For the Year ended December 31, 2014 2015 Customer Percent of Revenues Percent of Revenues A 27 % — B 12 % — C 11 % — D 11 % — E 10 % — F — 13 % G — 11 % H — 10 % Additionally, Customer B accounted for 27% of the Company’s accounts receivable balance at December 31, 2014, and Customer F accounted for 38% of the accounts receivable balance at December 31, 2015. The Company had one other customer that accounted for 25% of its accounts receivable balance at December 31, 2014, but did not exceed 10% of its revenues in 2014. The Company had one other customer that accounted for 38% of its accounts receivable balance at December 31, 2015, but did not exceed 10% of its revenues in 2015. The Company had one customer, Philips, who accounted for approximately 71% of its revenues in 2013. The Company had no other customers that accounted for greater than 10% of its revenues in 2013. The Company has no significant off-balance sheet risk such as foreign exchange contracts, option contracts, or other hedging arrangements. Allowance for Doubtful Accounts The Company evaluates the collectability of accounts receivable on a regular basis. The allowance for doubtful accounts, if any, is based upon various factors including the financial condition and payment history of customers, an overall review of collections experience on other accounts and economic factors or events expected to affect future collections experience. The Company’s accounts receivable consist primarily of amounts due from large, well-capitalized customers and while the Company reviews their creditworthiness, collectability is generally not an issue. The Company records an allowance for doubtful accounts, when necessary, based on the potential for collectability issues within the customer base. The Company’s allowance for doubtful accounts was $0 at December 31, 2014 and 2015. Product Warranty Customers are permitted to return defective products under the Company’s standard product warranty program. For CorPath Systems, the Company’s standard one-year warranty provides for the repair of any product that malfunctions. Return and replacement can only occur if a material breach of the warranty remains uncured for 30 days. A roll-forward of the Company’s warranty liability is as follows: Balance at December 31, 2013 $ 29 Provision for warranty obligations 96 Settlements (64 ) Balance at December 31, 2014 61 Provisions for warranty obligations 58 Settlements (51 ) Balance at December 31, 2015 $ 68 Inventories Inventories are valued at the lower of cost or market using the first-in, first-out (FIFO) method. The Company routinely monitors the recoverability of its inventory and records the lower of cost or market reserves based on current selling prices and reserves for excess and obsolete inventory based on historical and forecasted usage, as required. Scrap and excess manufacturing costs are charged to cost of revenue as incurred and not capitalized as part of inventories. The Company only capitalizes pre-launch inventory when purchased for commercial use and it deems regulatory approval to be probable. Property and Equipment Property and equipment is carried at cost. Major items and betterments are capitalized; maintenance and repairs are charged to expense as incurred. The Company capitalizes certain costs incurred in connection with developing or obtaining internal-use software. Software costs that do not meet capitalization criteria are expensed as incurred. Demonstration equipment represents internally manufactured capital equipment that is used on-site at trade shows and at customer locations to demonstrate the CorPath System. Field equipment represents internally manufactured capital equipment placed at customer locations under a program that involves the placement of a system at the customer’s site and the customer’s agreement to purchase a minimum number of cassettes each month. At December 31, 2015, the Company had placed six field equipment units and four units for a customer’s evaluation under such arrangements. Depreciation on the demonstration equipment is charged to selling, general and administrative and the deprecation on the field equipment is charged to cost of revenue. Depreciation is computed under the straight-line method over the estimated useful lives of the respective assets. Depreciation is provided over the following estimated asset lives: Machinery and equipment 5 years Computer equipment 3 years Office furniture and equipment 5 years Leasehold improvements Shorter of life of lease or useful life Vendor tooling 1.5 - 3 years, based on planned usage Software 4 years Demonstration equipment 3 years Field equipment 3 years Impairment of Long-Lived Assets The Company’s long-lived assets principally consist of property and equipment. The Company continually monitors events and changes in circumstances that could indicate carrying amounts of long-lived assets may not be recoverable. An impairment loss is recognized when expected cash flows are less than an asset’s carrying value. Accordingly, when indicators of impairment are present, the Company evaluates the carrying value of such assets in relation to the operating performance and estimated future undiscounted cash flows of the underlying assets. The Company’s policy is to record an impairment loss when it is determined that the carrying amount of the asset may not be recoverable. No such impairment changes have been recognized. Comprehensive Loss Comprehensive loss is comprised of net loss and changes in the unrealized gains and losses on marketable securities. Accumulated other comprehensive loss, a component of stockholders’ equity, is comprised of the cumulative unrealized gains and/or losses from the change in fair market value of the Company’s marketable securities. Accumulated other comprehensive loss was $14 as of December 31, 2015. Revenue Recognition The CorPath System is a capital medical device used by hospitals and surgical centers to perform heart catheterizations. Use of the CorPath System requires a sterile, single-use cassette (the “CorPath Cassette”), which are sold separately, for each procedure. Products are sold to customers with no rights of return. The Company recognizes revenue on the sale of products when the following criteria are met: ● Persuasive evidence of an arrangement exists ● The price to the buyer is fixed or determinable ● Collectability is reasonably assured ● Risk of loss transfers and the product is delivered. In each arrangement, the Company is responsible for installation of the CorPath System and initial user training, which services are deemed essential to the functionality of the system. Therefore, the Company recognizes system revenue when the CorPath System is delivered and installed, and accepted by the end user customer. Each CorPath System is sold with a standard one year warranty, which provides that the CorPath System will function as intended and during that one year period, the Company will either replace the product or a portion thereof or provide the necessary repair service during the Company’s normal service hours. The Company accrues for the estimated costs of the warranty once the CorPath System revenue is recognized. The Company generally enters into multiple element arrangements, which include the sale of a CorPath System with an initial order of CorPath Cassettes, and may include either a basic service plan or a premium service plan. The basic service plan provides for an extended warranty period and the premium service plan provides for the extended warranty as well as component upgrades, when and if they become available during the service plan period. Deliverables, which are accounted for as separate units of accounting under multiple-element arrangements include: (a) the CorPath System, including installation and initial training, which are subject to customer acceptance and (b) the initial shipment of CorPath Cassettes to the customer, and may include either (c) an extended warranty or (d) component upgrades. The Company recognizes revenue on multiple-element arrangements in accordance with Accounting Standards Update (“ASU”) 2009-13, Revenue Recognition (Topic 605): Multiple Deliverable Revenue Arrangements, based on the estimated selling price of each element. In accordance with ASU 2009-13, the Company uses vendor-specific objective evidence (“VSOE”), if available, to determine the selling price of each element. If VSOE is not available, the Company uses third-party evidence (“TPE”) to determine the selling price. If TPE is not available, the Company uses its best estimate to develop the estimated selling price (“BESP”). The Company uses BESP to determine the selling price of its systems as well as the basic and premium service plans. BESP is determined based on estimated costs plus a reasonable margin, and has generally been consistent with the price charged to the customer for such products and services. The determination of BESP also considers the price of the service plans charged to customers when such services are sold separately in subsequent transactions. The Company also uses BESP to determine the selling price of the initial order of cassettes, which considers the price at which it charges its customers when the cassettes are sold separately. Revenue related to basic service plans is recognized on a straight-line basis over the life of the service contract. Revenue related to premium service plans is recognized over the life of the service contract, with consideration given to the expected timing of costs to be incurred related to the delivery of component upgrades. Revenues from accessories are recorded upon delivery and services provided by the Company outside of a basic or premium service contract are recognized as the services are provided. There are no performance, cancellation, termination, and refund-type provisions under the Company’s multiple element arrangements. On January 21, 2011, the Company entered into a distributor agreement with Philips Medical Systems Nederland, B.V. (“Philips”) appointing Philips to be the sole worldwide distributor for the promotion and sale of the Company’s CorPath System. Under the agreement, Philips sold the equipment directly to the end user and the Company was responsible for installation and initial training. Revenue was recognized on a net basis based on the amount billed to Philips and upon acceptance of the system by the end-user customer. This agreement with Philips expired on August 7, 2014. The Company continues to sell CorPath Systems through Philips on a sale by sale basis under a non-exclusive arrangement under mutually agreeable terms, which may include a continued level of discounted pricing, until such time the Company either executes a new distribution arrangement with Philips or the Company no longer does business with Philips. At December 31, 2014 and 2015, there were no amounts outstanding from Philips. The Company also sells CorPath Cassettes under a CorPath Utilization Program (“CUP”), which is a multi-year arrangement that involves the placement of a CorPath System at a customer’s site free of charge and the customer agrees to purchase a minimum number of CorPath Cassettes each month at a premium over the regular price. The Company records revenue upon shipment of the cassettes based on the selling price of the CorPath Cassettes. The system is capitalized as field equipment in property and equipment and is depreciated on a straight line basis through cost of revenue over the estimated useful life of the system, which generally approximates the length of the CUP program contract, which is typically 36 months. The Company also offers a One-Stent program to demonstrate its confidence in the CorPath System’s ability to help accurately measure anatomy and precisely place only one stent per lesion. The Company provides eligible customers registered under the program a $1 credit against future CorPath Cassette purchases for a qualifying CorPath percutaneous coronary intervention (“PCI”) procedure which uses more than one stent per lesion. The estimated cost of honoring the potential obligation under the stent program is recorded as a reduction of revenue at the time of shipment. These costs have not been significant to date. The Company records shipping and handling costs as a selling expense in the period incurred, and records payments from customers for shipping costs as a reduction of selling expenses. Such amounts have not been material in the periods presented. The Company recorded medical device excise tax in the amount of $29, $40 and $34 for the years ended December 31, 2013, 2014 and 2015, respectively, which is included in selling, general and administrative expenses. At the present time the excise tax is suspended due to the operation of a provision in the Consolidated Appropriations Act of 2016, signed into law on December 18, 2015 but that two-year moratorium ends on December 31, 2017. Research and Development Costs for research and development are expensed as incurred. Research and development expense consists primarily of salaries, salary-related expenses and costs of contractors and materials. Income Taxes The Company accounts for income taxes using the liability method, whereby deferred tax asset and liability account balances are determined based on differences between financial reporting and tax basis of assets and liabilities and are measured using the enacted tax rates that will be in effect when the differences are expected to reverse. The Company provides a valuation allowance, if necessary, to reduce deferred tax assets to amounts that are realizable. The Company accounts for uncertain tax positions using a “more-likely-than-not” threshold for recognizing and resolving uncertain tax positions. The evaluation of uncertain tax positions is based on factors including, but not limited to, changes in tax law, the measurement of tax positions taken or expected to be taken in tax returns, the effective settlement of matters subject to audit, new audit activity and changes in facts or circumstances related to a tax position. The Company evaluates these tax positions on an annual basis. The Company also accrues for potential interest and penalties related to unrecognized tax benefits in income tax expense. The Company recognizes the tax benefit of tax positions to the extent that the benefit will more likely than not be realized. The determination as to whether the tax benefit will more likely than not be realized is based upon the technical merits of the tax position as well as consideration of the available facts and circumstances. Stock-Based Compensation The Company recognizes compensation costs resulting from the issuance of stock-based awards to employees and directors as an expense in the consolidated statements of operations over the requisite service period based on a measurement of fair value for each stock award. The awards issued to date have been stock options with service-based vesting periods over two or four years. The Company recognizes compensation costs resulting from the issuance of stock-based awards to non-employees as an expense in the consolidated statements of operations over the service period based on a measurement of fair value for each stock award at each performance date and period end. Prior to the completion of the reverse acquisition, the fair value of the common stock was determined by the Board of Directors after considering a broad range of factors, including the results obtained from an independent third-party valuation, the illiquid nature of an investment in the Company’s Common Stock, the Company’s historical financial performance and financial position, the Company’s future prospects and opportunity for liquidity events, and recent sale and offer prices of Common and Preferred Stock in private transactions negotiated at arm’s length. Subsequent to the completion of the reverse acquisition, the fair value of the Common Stock was obtained from quoted market prices on the OTCQB as provided by OTC Market Groups, Inc. In connection with the public offering in May 2015, the Company’s common stock was approved for listing on the NYSE MKT, where it commenced trading under the symbol “CVRS”. The following assumptions were used to estimate the fair value of stock options granted using the Black-Scholes-Merton option-pricing model (“Black-Scholes Model”): Years ended December 31, 2013 2014 2015 Risk-free interest rate 0.72% to 1.43 1.89% to 2.01% 1.54% to 1.97 Expected term in years 5.75 to 6.25 6.25 6.08 Expected volatility 80 50 50% Expected dividend yield 0 0 0% The risk-free interest rate assumption is based upon observed U.S. government security interest rates with a term that is consistent with the expected term of the Company’s employee stock options. The expected term is based on the average of the vesting period and contractual term of the Company’s options given the lack of historical data available. The Company does not pay a dividend, and is not expected to pay a dividend in the foreseeable future. Due to a lack of a public market for the Company’s Common Stock for an extended period of time, the Company utilized comparable public companies’ volatility rates as a proxy of its expected volatility for purposes of the Black-Scholes Model. Stock-based compensation expense is recorded net of estimated forfeitures and is adjusted periodically for actual forfeitures. The Company uses historical data to estimate forfeiture rates. For the years ended December 31, 2013, 2014 and 2015, forfeitures were estimated to be 4.9%, 6.0% and 5.0%, respectively. Warrant Liability The Company reviews the terms of warrants issued in connection with the applicable accounting guidance and classifies warrants as a long-term liability on the consolidated balance sheets if the warrant may conditionally obligate the Company to transfer assets, including repurchase of the Company’s capital stock, at some point in the future. Warrants to purchase shares of redeemable convertible preferred stock met these criteria and therefore required liability-classification. The Company classifies warrants within stockholders’ equity on the consolidated balance sheets if the warrants are considered to be indexed to the Company’s own capital stock, and otherwise would be recorded in stockholders’ equity. Liability-classified warrants are subject to re-measurement at each balance sheet date, and any change in fair value is recognized as a component of other income (expense) in the consolidated statements of operations. The Company estimated the fair value of these warrants at issuance and each balance sheet date thereafter using the Black-Scholes Model as described in the stock-based compensation section above, based on the estimated market value of the underlying Redeemable Convertible Preferred Stock at the valuation measurement date, the remaining contractual term of the warrant, risk-free interest rates, expected dividends and expected volatility of the price of the underlying redeemable convertible preferred stock. The fair value of the Redeemable Convertible Preferred Stock was determined by the Board of Directors after considering a broad range of factors, including the results obtained from an independent third-party valuation, the illiquid nature of an investment in the Company’s Redeemable Convertible Preferred Stock, the Company’s historical financial performance and financial position, the Company’s future prospects and opportunity for liquidity events, and recent sale and offer prices of Common and Preferred Stock in private transactions negotiated at arm’s length. The Company had warrants outstanding to purchase shares of Series A, D and E Redeemable Convertible Preferred Stock, which converted into warrants to purchase shares of Common Stock at the date of the Acquisition. Prior to the Acquisition, the warrant instruments required mark-to-market accounting which was recorded in the statements of operations based on their fair values determined using the Black-Scholes Model and the fair value of underlying Preferred Stock. The warrant instruments were re-valued for the last time at the date of the Acquisition and reclassified into stockholders’ equity in 2014, and at December 31, 2014 and 2015, the Company did not have a warrant liability. Related-Party Transactions On January 21, 2011, the Company entered into a distributor agreement with Philips appointing Philips to be the sole distributor for the promotion and sale of the Company’s CorPath System. The agreement was terminated on August 7, 2014. The Company continues to sell CorPath Systems through Philips on a sale by sale basis under a non-exclusive arrangement under mutually agreeable terms, which may include a continued level of discounted pricing, until such time the Company either executes a new distribution arrangement with Philips or the Company no longer does business with Philips. For the years ended December 31, 2013, 2014 and 2015, the Company recorded revenues of $630, $315 and $125, respectively, from shipments to Philips under the distribution agreement. At December 31, 2014 and 2015, there were no amounts outstanding from Philips, resulting from selling activity under the agreement. As of December 31, 2015, Koninklijke Philips, N.V. ("Philips' Parent"), held approximately 15% of the Company's outstanding Common Stock. Recent Accounting Pronouncements Not Yet Adopted In May 2014, the FASB issued ASU 2014-09—Revenue from Contracts with Customers, which amends FASB Accounting Standards Codification Topic 606. ASU 2014-09 provides a single, comprehensive revenue recognition model for all contracts with customers. This standard contains principles for the determination of the measurement of revenue and the timing of when such revenue is recognized. Revenue recognition will reflect the transfer of goods or services to customers at an amount that is expected to be earned in exchange for those goods or services. ASU 2014-09 was scheduled to be effective for annual reporting periods beginning after December 15, 2016, and early adoption was not permitted. In August 2015, the FASB issued ASU No. 2015-14—Revenue from Contracts with Customers: Deferral of Effective Date, which defers the effective date of ASU 2014-09 by one year. ASU 2014-09 is now effective for annual periods after December 15, 2017 including interim periods within that reporting period. Early adoption is permitted, but not before the original effective date. The Company is currently assessing the impact of this standard to its consolidated financial statements. In August 2014, the FASB issued ASU 2014-15, Disclosure of Uncertainties about an Entity’s Ability to Continue as a Going Concern. The amendments in this update will explicitly require a company’s management to assess an entity’s ability to continue as a going concern, and to provide related footnote disclosures in certain circumstances. The new standard will be effective in the first annual period ending after December 15, 2016. Early adoption is permitted. If this standard had been adopted as of December 31, 2015, the Company believes that it would have concluded there was not substantial doubt about its ability to continue as a going concern. However, the Company faces certain risks and uncertainties, as further described in Note 1, Nature of Operations, that could have affected this analysis. In January 2015, the FASB issued Financial Accounting Standards Update—Simplifying Income Statement Presentation by Eliminating the Concept of Extraordinary Items. Subtopic 225-20, Income Statement—Extraordinary and Unusual Items, previously required that an entity separately classify, present, and disclose extraordinary events and transactions. This update is effective for fiscal years, and interim periods within those fiscal years, beginning after December 15, 2015 and may be applied prospectively or retrospectively to all prior periods presented in the financial statements. Early adoption is permitted provided that the guidance is applied from the beginning of the fiscal year of adoption. The Company does not expect the impact of adoption to be material to its consolidate

Inventories

Inventories	12 Months Ended
	Dec. 31, 2015
Inventory Disclosure [Abstract]
Inventories	3. Inventories The Company’s inventories are valued at the lower of cost or market using the FIFO method and consist of the following: December 31, 2014 2015 Raw materials $ 737 $ 483 Work in progress 198 79 Finished goods 584 767 $ 1,519 $ 1,329 In the fourth quarter of 2015, the Company reclassified certain of its original equipment manufacturer (“OEM”) parts from raw materials to finished goods to be consistent with how all of its OEM parts were being classified. For the year ended December 31, 2014, the inventory balances include a reclassification of $124 from raw materials to finished goods in order to conform to the current year’s presentation.

Property and Equipment

Property and Equipment	12 Months Ended
	Dec. 31, 2015
Property, Plant and Equipment [Abstract]
Property and Equipment	4. Property and Equipment Property and equipment are stated at cost and are being depreciated using the straight-line basis over the assets’ estimated useful lives. Depreciation and amortization expense was $607, $622 and $706 for the fiscal years 2013, 2014 and 2015, respectively. Property and equipment consist of the following: December 31, 2014 2015 Machinery and equipment $ 334 $ 441 Computer equipment 273 286 Office furniture and equipment 355 360 Leasehold improvements 67 70 Vendor tooling 711 715 Software 490 498 Demonstration equipment 633 717 Field equipment 588 1,004 Construction in progress — 126 3,451 4,217 Less accumulated depreciation and amortization (2,167 ) (2,835 ) Property and equipment, net $ 1,284 $ 1,382 Construction in progress at December 31, 2015 relates to vendor tooling that is currently in the design and testing stage which will be used in the Company's production process.

Notes Receivable

Notes Receivable	12 Months Ended
	Dec. 31, 2015
Receivables [Abstract]
Notes Receivable	5. Notes Receivable On June 14, 2010, the Company loaned funds to certain stockholders of the Company for tax payments to be made to the Israel Tax Authority in connection with a tax ruling related to a reorganization that took place in 2008 and the Company received non-interest bearing notes receivable, which documented such loans. Total amount of notes receivable issued was $145. The notes receivable are repayable upon the disposition of the Company’s Common Stock. Notes receivable in the amount of $136 were outstanding at both December 31, 2014 and 2015. The Company assessed the notes receivable for impairment and concluded that there was no impairment indicators at December 31, 2014 and 2015. The Company does not believe there is any collection risk associated with the notes receivable at December 31, 2015. In February 2016, the Company received a payment of $65 related to this notes receivable balance as one of the stockholders had recently sold some of their shares of the Company's common stock.

Accrued Expenses

Accrued Expenses	12 Months Ended
	Dec. 31, 2015
Payables and Accruals [Abstract]
Accrued Expenses	6. Accrued Expenses Accrued expenses consist of the following: 2014 2015 Payroll and benefits $ 185 $ 79 Professional and consultant fees 496 444 Travel expenses 57 113 Product development costs 62 44 Commissions 85 187 Warranty 61 68 Interest 48 71 Other 143 193 $ 1,137 $ 1,199 _______________________ Certain items classified as "Other" in the prior year, travel expense and interest, were changed to conform with the current year presentation.

Long-Term Debt

Long-Term Debt	12 Months Ended
	Dec. 31, 2015
Debt Disclosure [Abstract]
Long-Term Debt	7. Long-Term Debt On June 11, 2014, the Company entered into a Loan and Security Agreement pursuant to which the lender agreed to make available to the Company $10,000 in two separate $5,000 loans under secured promissory notes. The initial note was made on June 11, 2014 in an aggregate principal amount equal to $5,000 (the “Initial Promissory Note”) and is repayable in equal monthly installments of principal and interest over 27 months beginning on July 1, 2015. Prior to July 1, 2015, the Company was required to make interest only payments. The Initial Promissory Note bears interest at a rate equal to the greater of (a) 11.25% or (b) 11.25% plus the Wall Street Journal Prime Rate, less 3.25%, and includes an additional interest payment of $125 due no later than October 1, 2017, which is accreted over the term of the loan. The effective interest rate of the Initial Promissory Note was 11.50% at December 31, 2015. On December 31, 2014, the Company borrowed the additional $5,000 (the “Second Promissory Note”) under the Loan and Security Agreement. The Second Promissory note is also repayable in equal monthly installments of principal and interest over 27 months beginning on July 1, 2015. Prior to July 1, 2015, the Company was required to make interest only payments. The Second Promissory Note bears interest at a rate equal to the greater of (a) 9.95% or (b) 9.95% plus the Wall Street Journal Prime Rate, less 3.25%, and also includes an additional interest payment of $125 due no later than October 1, 2017, which is accreted over the term of the loan. The effective interest rate of the Second Promissory Note was 10.20% at December 31, 2015. The notes are secured by substantially all the assets of the Company. In connection with the Initial Promissory Note, the Company issued the lender warrants to purchase 177,514 shares of the Company’s Common Stock at an exercise price of $1.41 per share. The fair value of the warrant issued to the lender was determined to be $230 at the date of issuance, and was recorded as a discount on the debt. Additionally, in connection with the Second Promissory Note, the Company issued the lender warrants to purchase 177,514 shares of the Company’s Common Stock at an exercise price of $1.41 per share. The fair value of the warrant issued to the lender was determined to be $619 at the date of issuance, and was recorded as a discount on the debt. The Company amortizes the debt discount to interest expense over the term of the debt using the effective interest method. The Company estimated the fair value of these warrants using the Black-Scholes Model based on the estimated market value of the underlying Common Stock at the valuation measurement date, the remaining contractual term of the warrant, risk-free interest rates, expected dividends and expected volatility of the price of the underlying common stock. The Company used the following assumptions for the valuation of its warrants issued on the following dates: June 11, 2014 December 31, 2014 Risk-free interest rate 2.5 % 2.17 % Dividend yield 0.0 % 0.0 % Expected volatility 50.0 % 50.0 % Expected term (years) 10.00 9.44 The Loan and Security Agreement also contains covenants which include certain restrictions with respect to subsequent indebtedness, liens, loans and investments, asset sales and share repurchases and other restricted payments, subject to certain exceptions. The Loan and Security Agreement also contains financial reporting obligations. An event of default under the Loan and Security Agreement includes, but is not limited to, breach of covenants, insolvency, and occurrence of any default under any agreement or obligation of the Company. In addition, the Loan and Security Agreement contains a customary material adverse effect clause which states that in the event of a material adverse effect, an event of default would occur and the lender has the option to accelerate and demand payment of all or any part of the loan. A material adverse effect is defined in the Loan and Security Agreement as a material change in the Company’s business, operations, properties, assets or financial condition or a material impairment of its ability to perform all obligations under its Loan and Security Agreement. The Company was not in default of any conditions under the Loan and Security Agreements as of December 31, 2015. Borrowings outstanding, net of unamortized discount of $414 and $150 of additional interest payments, amounted to $7,715 at December 31, 2015. Future principal payments under the borrowing arrangement as of December 31, 2015 are as follows: Year ending December 31: 2016 $ 4,373 2017 3,605 $ 7,978

Income Taxes

Income Taxes	12 Months Ended
	Dec. 31, 2015
Income Tax Disclosure [Abstract]
Income Taxes	8. Income Taxes There was no federal or state provision for income taxes for the years ended December 31, 2013, 2014 or 2015 due to the Company’s operating losses and a full valuation allowance on deferred income tax assets for all periods since inception. All of the Company’s loss before provision for income taxes is attributable to its United States operations. The Company’s effective income tax rate differs from the statutory federal income tax rate as follows: Years Ended December 31, 2013 2014 2015 Statutory U.S. federal rate 34.0 % 34.0 % 34.0 % State income tax 4.7 1.7 3.7 Permanent items 0.6 (3.8 ) (0.4 ) Change in taxing status in Massachusetts to a manufacturer — (4.9 ) — Other (0.8 ) (0.7 ) (0.5 ) Change in state tax rate — — 0.7 Federal R&D credits 2.0 1.2 1.3 State R&D and other credits 0.5 0.7 0.5 Change in valuation allowance (41.0 ) (28.2 ) (39.3 ) Total expense (benefit) — % — % — % Deferred income taxes reflect the net tax effects of temporary differences between the carrying amounts of assets and liabilities for financial reporting purposes and the amounts used for income tax purposes. Significant components of the Company’s deferred tax assets and the related valuation allowance were as follows: December 31, 2014 2015 Deferred income tax assets: Operating loss carryforwards $ 20,178 $ 30,832 Start-up expenditures 2,807 2,711 Property and equipment 46 28 Intangible assets 2,589 — Stock-based compensation expense 738 788 Research and development credit carryforwards 1,216 1,746 Accrued expenses and other 307 482 Total deferred income tax assets 27,881 36,587 Valuation allowance (27,881 ) (36,587 ) Net deferred income tax assets $ — $ — The Company has provided a full valuation allowance against the deferred income tax assets, since it has a history of losses, which are all attributable to the U.S. and currently does not have enough positive evidence required under U.S. GAAP to reverse its valuation allowance. Management does not believe it is more likely than not that its deferred tax assets relating to the loss carryforwards and other temporary differences will be realized in the future. For the years ended December 31, 2014 and 2015, the valuation allowance increased by $6,912 and $8,706 respectively, resulting principally from increased operating loss carryforward. Deferred tax assets relating to tax benefits of employee share-based compensation have been reduced for stock options exercised in periods in which the Company was in a net operating loss (NOL) position. Some exercises resulted in tax deductions in excess of previously recorded benefits based on the stock option value at the time of the grant (windfalls). Althougth windfalls are reflected in NOL carryforwards in the tax return, the additional tax benefit associated with the windfalls is not recognized until the deduction reduces taxes payable pursuant to U.S. GAAP. Accordingly, since the tax benefit does not reduce the Company's current taxes payable due to NOL carryforwards, these windfall tax benefits are not reflected in the Company's NOLs in deferred tax assets. Windfalls included in NOL carryforwards but not reflected in deferred tax assets as of December 31, 2015 totaled $850. At December 31, 2015, the Company had U.S. federal and state net operating loss carryforwards of approximately $82,989 and $56,585, respectively, that can be carried forward and offset against future taxable income. These net operating loss carryforwards will begin to expire in 2028. Utilization of net operating losses may be subject to a substantial annual limitation due to the “change in ownership” provisions of the Internal Revenue Code of 1986, and similar state provisions. The annual limitation may result in the expiration of net operating losses before utilization. The Company has determined no ownership changes have occurred to date that would place limitations on the ability to use net loss carryforwards, but will continue to monitor any future shifts in ownership that could cause limitations. Significant judgment is required in evaluating the Company’s tax positions and in determining the Company’s provision for income taxes. In the ordinary course of business, there are many transactions and calculations for which the ultimate tax determination is uncertain. As of December 31, 2015, the Company was not under audit in any tax jurisdiction. The U.S. statute of limitations will remain open to examination by the tax authorities until the utilization of net operating loss carryforwards. The Company accrues interest and penalties, if any, related to unrecognized tax benefits in income tax expense.

Stockholders' Equity

Stockholders' Equity	12 Months Ended
	Dec. 31, 2015
Equity [Abstract]
Stockholders' Equity	9. Stockholders’ Equity The Company is authorized to issue 250,000,000 shares of common stock. Holders of Common Stock are entitled to vote on all matters and are entitled to the number of votes equal to the number of common shares held. Holders of Common Stock shall be entitled to receive dividends when and if declared by the Board of Directors. No dividends have been declared to date. In certain events, including the liquidation, dissolution or winding up of the Company, the remaining assets of the Company shall be distributed ratably among the holders of Common Stock. The Company is authorized to issue 10,000,000 shares of preferred stock. As of December 31, 2014 and 2015, the Company had no shares of preferred stock issued or outstanding. At December 31, 2015, there were 23,569,951 shares of common stock reserved for the potential exercise of warrants (5,207,379) and stock options (8,778,503), and 9,584,069 shares that are available for grant under the 2014 Stock Award Plan.

Stock-based Compensation

Stock-based Compensation	12 Months Ended
	Dec. 31, 2015
Disclosure of Compensation Related Costs, Share-based Payments [Abstract]
Stock-based Compensation	10. Stock-Based Compensation In connection with the Company's reverse acquisition in August 2014, Corindus exchanged options to purchase shares of its Common Stock for YIDI’s options to purchase shares of YIDI’s Common Stock (the “Replacement Plan Options”). The 2014 Stock Award Plan is the replacement plan for options previously awarded under the Corindus, Inc. 2006 Umbrella Option Plan and the Corindus, Inc. 2008 Stock Incentive Plan and is the plan under which all future Company options will be issued. The 2014 Stock Award Plan was limited to award issuances which in the aggregate could not exceed 9,035,016 shares, all of which shares will be used for the issuance of the Company stock-based awards, including options to purchase common stock, restricted stock and restricted stock units. Replacement Plan Options are exercisable for up to ten years from the date of original vesting commencement date of the options. On April 30, 2015, the Company’s Board of Directors and shareholders owning a majority of the Company’s outstanding shares of common stock approved an increase in the authorized shares of common stock under the 2014 Stock Award Plan from 9,035,016 shares to 18,661,856 shares. A summary of the activity under the Company’s stock option plans is as follows. Such information has been retrospectively adjusted to give effect to the exchange of stock options that occurred upon the Acquisition. Options Weighted- Average Exercise Price Weighted- Average Remaining Contractual Term (Years) Aggregate Intrinsic Value Outstanding at December 31, 2014 8,678,017 $ 0.64 6.30 $ 31,359 Granted 1,454,486 $ 3.51 Exercised (347,392 ) $ 0.28 Cancelled (1,006,608 ) $ 0.80 Outstanding at December 31, 2015 8,778,503 $ 1.11 5.98 $ 18,876 Exercisable at December 31, 2015 6,673,104 $ 0.63 5.01 $ 17,220 Vested and expected to vest at December 31, 2015 8,673,233 $ 1.09 5.95 $ 18,813 Stock-based compensation expense was allocated based on the employees’ function as follows: Years ended December 31, 2013 2014 2015 Research and development $ 59 $ 95 $ 74 Selling, general and administrative 270 282 431 $ 329 $ 377 $ 505 The fair value of employee options is estimated on the date of each grant using the Black-Scholes Model. The weighted-average grant date fair value of options granted during the year ended December 31, 2013, 2014 and 2015 were $0.24, $0.16 and $1.80, respectively. As of December 31, 2015, there was approximately $2,415 of unrecognized compensation cost related to non-vested stock-based compensation arrangements under the 2014 Stock Award Plan. That cost was expected to be recognized over a weighted-average period of 3.38 years. The total intrinsic value of options exercised in 2015 was $995.

Warrants to Purchase Common Sto

Warrants to Purchase Common Stock	12 Months Ended
	Dec. 31, 2015
Text Block [Abstract]
Warrants to Purchase Common Stock	11. Warrants to Purchase Common Stock In connection with the Acquisition, the Company exchanged warrants to purchase 201,178 shares of Corindus, Inc. Series A, D and E Redeemable Convertible Preferred Stock at an average exercise price of $26.63 per share to warrants to purchase 5,029,865 shares of the Company’s Common Stock at the average exercise price of $1.07 per share. Prior to the Acquisition, the warrants were treated as liability instruments and were measured on a recurring basis at their fair value with inputs categorized as Level 3 in the fair value hierarchy. The resulting gain or loss on revaluation was recorded as other income (expense) in the consolidated statements of operations. The Company estimated the fair value of these warrants using the Black-Scholes Model based on the estimated market value of the underlying Redeemable Convertible Preferred Stock at the valuation measurement date, the remaining contractual term of the warrant, risk-free interest rates, expected dividends and expected volatility of the price of the underlying Redeemable Convertible Preferred Stock. The Company revalued the warrants for the final time at the date of the Acquisition, which resulted in a charge of $2,421 for the year ended December 31, 2014. A roll forward of the warrant liability is as follows: Balance at December 31, 2013 $ 3,152 Issuance of warrants in connection with lending arrangement 230 Revaluation of warrants 2,421 Reclassification of warrant liability to stockholders’ equity (5,803 ) Balance at December 31, 2014 $ — The Company used the following assumptions for the valuation of its warrant liability: August 12, 2014 Risk-free interest rate 1.025 % Dividend yield 0.0 % Expected volatility 50.0 % Expected term (years) 3.5 The Company has following warrants outstanding at December 31, 2015: Exercise Price Date of Expiration Number of Warrants $1.06 October 11, 2017 4,728,191 $0.76 May 31, 2017 124,160 $1.41 May 28, 2020 355,028 5,207,379

Commitments and Contingencies

Commitments and Contingencies	12 Months Ended
	Dec. 31, 2015
Commitments and Contingencies Disclosure [Abstract]
Commitments and Contingencies	12. Commitments and Contingencies The Company has an operating lease for approximately 26,402 square feet at its corporate headquarters and manufacturing plant in Waltham, Massachusetts, which expires in January 2018 and the Company has an option to extend for an additional five years at market rates or the rates payable in the final years of the term of the lease, whichever is greater. The lease terms include escalating rent payments over the life of the lease and rent expense is recognized over the life of the lease on a straight-line basis. The difference between the amount expensed and actual rent payments are recorded as a deferred rent included within accrued expenses in the consolidated balance sheets. In connection with the lease, the Company is required to maintain a security deposit with its landlord, which declines every six months during the lease until January 2016, at which point the amount remains constant at $134. The total amount of the security deposit is approximately $178 at December 31, 2015, of which $45 is included in prepaid expenses and other current assets. The Company also leases copiers and vehicles under operating leases that expire at various points through 2019. Total rent expense was $584, $577 and $574 for the years ending December 31, 2013, 2014 and 2015, respectively. At December 31, 2015, the Company’s future minimum lease payments are indicated below: Year ending December 31: Total Lease Payments 2016 $ 573 2017 586 2018 49 Total $ 1,208 The Company is subject to potential claims from time to time in the ordinary course of business. At December 31, 2015, the Company is not subject to any significant asserted or unasserted claims.

Net Loss per Share

Net Loss per Share	12 Months Ended
	Dec. 31, 2015
Earnings Per Share [Abstract]
Net Loss per Share	13. Net Loss per Share Basic net loss per share is computed by dividing net loss by the weighted average shares of common stock outstanding for each period. Diluted net loss per share is the same as basic net loss per share since the Company has net losses for each period presented. The following common stock equivalents were excluded from the calculation of diluted net loss per share for the periods indicated because including them would have had an anti-dilutive effect: Years Ended December 31, 2013 2014 2015 Options to purchase Common Stock 8,548,357 8,678,017 8,778,503 Warrants to purchase Common Stock 4,852,351 5,207,379 5,207,379 Total 13,400,708 13,885,396 13,985,882

Restructuring Charge

Restructuring Charge	12 Months Ended
	Dec. 31, 2015
Restructuring and Related Activities [Abstract]
Restructuring Charge	14. Restructuring Charge During 2014, the Company initiated reductions in workforce to control costs while the Company pursued new financing alternatives. During 2014, the Company recorded $175 in restructuring charges for severance and related costs, which were paid in 2014.

401(k) Plan

401(k) Plan	12 Months Ended
	Dec. 31, 2015
Compensation and Retirement Disclosure [Abstract]
401(k) Plan	15. 401(k) Plan The Company has a tax-qualified employee savings and retirement 401(k) plan, covering all qualified employees. Participants may elect a salary deferral up to the statutorily prescribed annual limit for tax-deferred contributions. The Company has not made any matching contributions to date.

Selected Quarterly Financial Da

Selected Quarterly Financial Data (Unaudited)	12 Months Ended
	Dec. 31, 2015
Quarterly Financial Information Disclosure [Abstract]
Selected Quarterly Financial Data (Unaudited)	16. Selected Quarterly Financial Data (Unaudited) The following table presents unaudited operating results for each of the Company’s quarters in the years ended December 31, 2015 and 2014: Fiscal Year 2015 Quarters First Second Third Fourth Year Revenue $ 776 $ 909 $ 212 $ 832 $ 2,729 Cost of revenue 801 941 722 1 ,260 3 ,724 Gross profit (loss) (25 ) (32 ) (510 ) (428 ) (995 ) Operating expenses 6 ,747 6 ,839 6 ,148 6 ,442 26,176 Operating loss (6,772 ) (6,871 ) (6,658 ) (6,870 ) (27,171 ) Total other expense, net (397 ) (432 ) (404 ) (359 ) (1,592 ) Net loss $ (7,169 ) $ (7,303 ) $ (7,062 ) $ (7,229 ) $ (28,763 ) Net loss per share - basic and diluted $ (0.07 ) $ (0.07 ) $ (0.06 ) $ (0.06 ) $ (0.25 ) Fiscal Year 2014 Quarters First Second Third Fourth Year Revenue $ 730 $ 1,077 $ 554 $ 622 $ 2,983 Cost of revenue 1 ,383 1 ,058 793 1 ,670 (1) 4 ,904 Gross profit (loss) (653 ) 19 (239 ) (1,048 ) (1,921 ) Operating expenses 4 ,949 4 ,388 5 ,148 5 ,299 19,784 Operating loss (5,602 ) (4,369 ) (5,387 ) (6,347 ) (21,705 ) Total other income (expense) 1 ,768 (1,341 ) (3,062 ) (201 ) (2,836 ) Net loss $ (3,834 ) $ (5,710 ) $ (8,449 ) $ (6,548 ) $ (24,541 ) Net loss per share - basic and diluted $ (0.05 ) $ (0.08 ) $ (0.10 ) $ (0.06 ) $ (0.29 ) ___________________ (1)

Subsequent Events

Subsequent Events	12 Months Ended
	Dec. 31, 2015
Subsequent Events [Abstract]
Subsequent Events	17. Subsequent Events The Company has evaluated all events or transactions that occurred after December 31, 2015 through the date of filing of the Form 10-K. In the judgment of management, there were no material events that impacted the consolidated financial statements or disclosures.

Significant Accounting Polici25

Significant Accounting Policies (Policies)	12 Months Ended
	Dec. 31, 2015
Accounting Policies [Abstract]
Principles of Consolidation	Principles of Consolidation The consolidated financial statements include the accounts of the Company and its wholly owned subsidiaries, Corindus, Inc. and Corindus Security Corporation, which was created on December 21, 2012 to hold and invest the proceeds from issuance of equity. All intercompany transactions and balances have been eliminated in consolidation. The functional currency of both wholly-owned subsidiaries is the U.S. dollar and, therefore, the Company has not recorded any currency translation adjustments. In the fourth quarter of 2014, the Company participated in the formation of a not-for-profit, which was established to generate awareness of the health risks linked to the use of fluoroscopy in hospital catheterization. As of December 31, 2015, the Company’s Chief Executive Officer and one of its senior executives represented two of the three voting members of the board of directors of the entity. As a result, under the voting model used for the consolidation of related parties, which are controlled by a company, the Company has consolidated the financial statements of the entity, and recognized expenses of $18 and $386 for the years ended December 31, 2014 and 2015, respectively. The entity had assets and liabilities of $56 and $75, respectively, on the Company's balance sheet at December 31, 2015. The entity did not have any assets or liabilities on the Company's balance sheet at December 31, 2014.
Segment Information	Segment Information The Company operates in one business segment, which is the development, marketing and sales of robotic-assisted vascular interventions. Operating segments are identified as components of an enterprise about which separate discrete financial information is available for evaluation by the chief operating decision maker in making decisions regarding resource allocation and assessing performance. To date, the chief operating decision maker has made such decisions and assessed performance at the company level, as one segment. The Company’s chief operating decision maker is the Chief Executive Officer. Revenues from domestic customers were $896, $2,068 and $2,684 for the years ending December 31, 2013, 2014 and 2015, respectively. Revenues from international customers, primarily in Dubai and Israel, were $0, $915 and $45 for the years ending December 31, 2013, 2014 and 2015, respectively.
Use of Estimates	Use of Estimates The process of preparing financial statements in conformity with accounting principles generally accepted in the United States (“U.S. GAAP”) requires management to make estimates and assumptions that affect the reported amounts of assets and liabilities and disclosure of assets and liabilities at the date of the financial statements. Such management estimates include those relating to revenue recognition, inventory valuation, assumptions used in the valuation of stock-based awards, and valuation allowances against deferred income tax assets. Actual results could differ from those estimates.
Cash Equivalents	Cash Equivalents The Company considers highly liquid short-term investments, which consists of money market funds and certificates of deposit with original maturity dates of three months or less at the date of purchase, to be cash equivalents. From time to time, the Company’s cash balances may exceed federal deposit insurance limits.
Marketable Securities	Marketable Securities The Company determines the appropriate classification of marketable securities at the time of purchase and reevaluates such designation at each balance sheet date. The Company has classified all of its marketable securities at December 31, 2015 as “available-for-sale” pursuant to ASC 320, Investments – Debt and Equity Securities. The Company records available-for-sale securities at fair value, with the unrealized gains and losses included in accumulated other comprehensive loss in stockholders’ equity. The Company adjusts the cost of available-for-sale debt securities for amortization of premiums and accretion of discounts to maturity. The Company includes such amortization and accretion in interest and other income (expense). The cost of securities sold is based on the specific identification method. The Company includes interest income on securities classified as available-for-sale in interest and other income (expense). The Company reviews marketable securities for other-than-temporary impairment whenever the fair value of a marketable security is less than the amortized cost and evidence indicates that a marketable security’s carrying amount is not recoverable within a reasonable period of time. Other-than-temporary impairments of investments are recognized in the consolidated statements of operations if the Company has experienced a credit loss, has the intent to sell the marketable security, or if it is more likely than not that the Company will be required to sell the marketable security before recovery of the amortized cost basis. At December 31, 2015, the balance in the Company’s accumulated other comprehensive loss was composed solely of activity related to the Company’s available-for-sale securities. There were no realized gains or losses recognized on the maturity of available-for-sale securities during the year ended December 31, 2015, and as a result, the Company did not reclassify any amount out of accumulated other comprehensive loss during that same period. The aggregate fair value of securities held by the Company in an unrealized loss position for less than twelve months as of December 31, 2015 consists of 13 certificates of deposit and two U.S. Treasuries. The Company has the intent and ability to hold such securities until recovery. As of December 31, 2015, the Company's available-for-sale securities had remaining maturities no greater than one year. The Company determined that there was no material change in the credit risk of the above investments. As a result, the Company determined it did not hold any investments with an other-than-temporary impairment as of December 31, 2015. The following table summarizes available-for-sale securities held at December 31, 2015: Description Amortized Cost Unrealized Gain Unrealized Loss Fair Value December 31, 2015 U.S. government treasuries $ 15,885 $ 1 $ (10 ) $ 15,876 Certificates of deposit 4,653 — (5 ) 4,648 Total $ 20,538 $ 1 $ (15 ) $ 20,524 Certain short-term securities with original maturities of less than 90 days are included in cash and cash equivalents on the consolidated balance sheet at December 31, 2015 and are not included in the table above. The Company did not hold any available-for-sale securities at December 31, 2014.
Fair Value of Financial Instruments	Fair Value Measurements In accordance with ASC 820, Fair Value Measurements and Disclosures, the Company generally defines fair value as the price that would be received to sell an asset or paid to transfer a liability in an orderly transaction between market participants at the measurement date (exit price). The Company uses a three-tier fair value hierarchy, which classifies the inputs used in measuring fair values. The hierarchy gives the highest priority to unadjusted quoted prices in active markets for identical assets or liabilities (Level 1 measurements), and the lowest priority to unobservable inputs (Level 3 measurements). The three levels of the fair value hierarchy are described below: ● Level 1 – ● Level 2 – ● Level 3 – The following table sets forth the Company’s assets that are measured at fair value on a recurring basis as of December 31, 2015: Fair value measurement category Description Total Quoted prices in active markets Significant other observable inputs Significant unobservable inputs December 31, 2015: Assets: Cash equivalents $ 6,356 $ 6,107 $ 249 $ — Marketable securities: U.S. government treasuries 15,876 15,876 — — Certificates of deposit 4,648 — 4,648 — Total assets $ 26,880 $ 21,983 $ 4,897 $ — The Company’s financial instruments of deposits and notes receivable are carried at cost and approximate their fair values given the liquid nature of such items. The fair value of the Company’s long-term debt amounted to $9,111 and $7,715 at December 31, 2014 and 2015, respectively, based on discounted cash flow analysis, which included Level 3 inputs and fair value approximates recorded amounts.
Concentrations of Credit Risk and Significant Customers	Concentrations of Credit Risk and Significant Customers The Company had the following customers that accounted for greater than 10% of its revenues for the year ended December 31, 2014 and 2015, respectively: For the Year ended December 31, 2014 2015 Customer Percent of Revenues Percent of Revenues A 27 % — B 12 % — C 11 % — D 11 % — E 10 % — F — 13 % G — 11 % H — 10 % Additionally, Customer B accounted for 27% of the Company’s accounts receivable balance at December 31, 2014, and Customer F accounted for 38% of the accounts receivable balance at December 31, 2015. The Company had one other customer that accounted for 25% of its accounts receivable balance at December 31, 2014, but did not exceed 10% of its revenues in 2014. The Company had one other customer that accounted for 38% of its accounts receivable balance at December 31, 2015, but did not exceed 10% of its revenues in 2015. The Company had one customer, Philips, who accounted for approximately 71% of its revenues in 2013. The Company had no other customers that accounted for greater than 10% of its revenues in 2013. The Company has no significant off-balance sheet risk such as foreign exchange contracts, option contracts, or other hedging arrangements.
Allowance for Doubtful Accounts	Allowance for Doubtful Accounts The Company evaluates the collectability of accounts receivable on a regular basis. The allowance for doubtful accounts, if any, is based upon various factors including the financial condition and payment history of customers, an overall review of collections experience on other accounts and economic factors or events expected to affect future collections experience. The Company’s accounts receivable consist primarily of amounts due from large, well-capitalized customers and while the Company reviews their creditworthiness, collectability is generally not an issue. The Company records an allowance for doubtful accounts, when necessary, based on the potential for collectability issues within the customer base. The Company’s allowance for doubtful accounts was $0 at December 31, 2014 and 2015.
Product Warranty	Product Warranty Customers are permitted to return defective products under the Company’s standard product warranty program. For CorPath Systems, the Company’s standard one-year warranty provides for the repair of any product that malfunctions. Return and replacement can only occur if a material breach of the warranty remains uncured for 30 days. A roll-forward of the Company’s warranty liability is as follows: Balance at December 31, 2013 $ 29 Provision for warranty obligations 96 Settlements (64 ) Balance at December 31, 2014 61 Provisions for warranty obligations 58 Settlements (51 ) Balance at December 31, 2015 $ 68
Inventories	Inventories Inventories are valued at the lower of cost or market using the first-in, first-out (FIFO) method. The Company routinely monitors the recoverability of its inventory and records the lower of cost or market reserves based on current selling prices and reserves for excess and obsolete inventory based on historical and forecasted usage, as required. Scrap and excess manufacturing costs are charged to cost of revenue as incurred and not capitalized as part of inventories. The Company only capitalizes pre-launch inventory when purchased for commercial use and it deems regulatory approval to be probable.
Property and Equipment	Property and Equipment Property and equipment is carried at cost. Major items and betterments are capitalized; maintenance and repairs are charged to expense as incurred. The Company capitalizes certain costs incurred in connection with developing or obtaining internal-use software. Software costs that do not meet capitalization criteria are expensed as incurred. Demonstration equipment represents internally manufactured capital equipment that is used on-site at trade shows and at customer locations to demonstrate the CorPath System. Field equipment represents internally manufactured capital equipment placed at customer locations under a program that involves the placement of a system at the customer’s site and the customer’s agreement to purchase a minimum number of cassettes each month. At December 31, 2015, the Company had placed six field equipment units and four units for a customer’s evaluation under such arrangements. Depreciation on the demonstration equipment is charged to selling, general and administrative and the deprecation on the field equipment is charged to cost of revenue. Depreciation is computed under the straight-line method over the estimated useful lives of the respective assets. Depreciation is provided over the following estimated asset lives: Machinery and equipment 5 years Computer equipment 3 years Office furniture and equipment 5 years Leasehold improvements Shorter of life of lease or useful life Vendor tooling 1.5 - 3 years, based on planned usage Software 4 years Demonstration equipment 3 years Field equipment 3 years
Impairment of Long-Lived Assets	Impairment of Long-Lived Assets The Company’s long-lived assets principally consist of property and equipment. The Company continually monitors events and changes in circumstances that could indicate carrying amounts of long-lived assets may not be recoverable. An impairment loss is recognized when expected cash flows are less than an asset’s carrying value. Accordingly, when indicators of impairment are present, the Company evaluates the carrying value of such assets in relation to the operating performance and estimated future undiscounted cash flows of the underlying assets. The Company’s policy is to record an impairment loss when it is determined that the carrying amount of the asset may not be recoverable. No such impairment changes have been recognized.
Comprehensive Loss	Comprehensive Loss Comprehensive loss is comprised of net loss and changes in the unrealized gains and losses on marketable securities. Accumulated other comprehensive loss, a component of stockholders’ equity, is comprised of the cumulative unrealized gains and/or losses from the change in fair market value of the Company’s marketable securities. Accumulated other comprehensive loss was $14 as of December 31, 2015.
Revenue Recognition	Revenue Recognition The CorPath System is a capital medical device used by hospitals and surgical centers to perform heart catheterizations. Use of the CorPath System requires a sterile, single-use cassette (the “CorPath Cassette”), which are sold separately, for each procedure. Products are sold to customers with no rights of return. The Company recognizes revenue on the sale of products when the following criteria are met: ● Persuasive evidence of an arrangement exists ● The price to the buyer is fixed or determinable ● Collectability is reasonably assured ● Risk of loss transfers and the product is delivered. In each arrangement, the Company is responsible for installation of the CorPath System and initial user training, which services are deemed essential to the functionality of the system. Therefore, the Company recognizes system revenue when the CorPath System is delivered and installed, and accepted by the end user customer. Each CorPath System is sold with a standard one year warranty, which provides that the CorPath System will function as intended and during that one year period, the Company will either replace the product or a portion thereof or provide the necessary repair service during the Company’s normal service hours. The Company accrues for the estimated costs of the warranty once the CorPath System revenue is recognized. The Company generally enters into multiple element arrangements, which include the sale of a CorPath System with an initial order of CorPath Cassettes, and may include either a basic service plan or a premium service plan. The basic service plan provides for an extended warranty period and the premium service plan provides for the extended warranty as well as component upgrades, when and if they become available during the service plan period. Deliverables, which are accounted for as separate units of accounting under multiple-element arrangements include: (a) the CorPath System, including installation and initial training, which are subject to customer acceptance and (b) the initial shipment of CorPath Cassettes to the customer, and may include either (c) an extended warranty or (d) component upgrades. The Company recognizes revenue on multiple-element arrangements in accordance with Accounting Standards Update (“ASU”) 2009-13, Revenue Recognition (Topic 605): Multiple Deliverable Revenue Arrangements, based on the estimated selling price of each element. In accordance with ASU 2009-13, the Company uses vendor-specific objective evidence (“VSOE”), if available, to determine the selling price of each element. If VSOE is not available, the Company uses third-party evidence (“TPE”) to determine the selling price. If TPE is not available, the Company uses its best estimate to develop the estimated selling price (“BESP”). The Company uses BESP to determine the selling price of its systems as well as the basic and premium service plans. BESP is determined based on estimated costs plus a reasonable margin, and has generally been consistent with the price charged to the customer for such products and services. The determination of BESP also considers the price of the service plans charged to customers when such services are sold separately in subsequent transactions. The Company also uses BESP to determine the selling price of the initial order of cassettes, which considers the price at which it charges its customers when the cassettes are sold separately. Revenue related to basic service plans is recognized on a straight-line basis over the life of the service contract. Revenue related to premium service plans is recognized over the life of the service contract, with consideration given to the expected timing of costs to be incurred related to the delivery of component upgrades. Revenues from accessories are recorded upon delivery and services provided by the Company outside of a basic or premium service contract are recognized as the services are provided. There are no performance, cancellation, termination, and refund-type provisions under the Company’s multiple element arrangements. On January 21, 2011, the Company entered into a distributor agreement with Philips Medical Systems Nederland, B.V. (“Philips”) appointing Philips to be the sole worldwide distributor for the promotion and sale of the Company’s CorPath System. Under the agreement, Philips sold the equipment directly to the end user and the Company was responsible for installation and initial training. Revenue was recognized on a net basis based on the amount billed to Philips and upon acceptance of the system by the end-user customer. This agreement with Philips expired on August 7, 2014. The Company continues to sell CorPath Systems through Philips on a sale by sale basis under a non-exclusive arrangement under mutually agreeable terms, which may include a continued level of discounted pricing, until such time the Company either executes a new distribution arrangement with Philips or the Company no longer does business with Philips. At December 31, 2014 and 2015, there were no amounts outstanding from Philips. The Company also sells CorPath Cassettes under a CorPath Utilization Program (“CUP”), which is a multi-year arrangement that involves the placement of a CorPath System at a customer’s site free of charge and the customer agrees to purchase a minimum number of CorPath Cassettes each month at a premium over the regular price. The Company records revenue upon shipment of the cassettes based on the selling price of the CorPath Cassettes. The system is capitalized as field equipment in property and equipment and is depreciated on a straight line basis through cost of revenue over the estimated useful life of the system, which generally approximates the length of the CUP program contract, which is typically 36 months. The Company also offers a One-Stent program to demonstrate its confidence in the CorPath System’s ability to help accurately measure anatomy and precisely place only one stent per lesion. The Company provides eligible customers registered under the program a $1 credit against future CorPath Cassette purchases for a qualifying CorPath percutaneous coronary intervention (“PCI”) procedure which uses more than one stent per lesion. The estimated cost of honoring the potential obligation under the stent program is recorded as a reduction of revenue at the time of shipment. These costs have not been significant to date. The Company records shipping and handling costs as a selling expense in the period incurred, and records payments from customers for shipping costs as a reduction of selling expenses. Such amounts have not been material in the periods presented. The Company recorded medical device excise tax in the amount of $29, $40 and $34 for the years ended December 31, 2013, 2014 and 2015, respectively, which is included in selling, general and administrative expenses. At the present time the excise tax is suspended due to the operation of a provision in the Consolidated Appropriations Act of 2016, signed into law on December 18, 2015 but that two-year moratorium ends on December 31, 2017.
Research and Development	Research and Development Costs for research and development are expensed as incurred. Research and development expense consists primarily of salaries, salary-related expenses and costs of contractors and materials.
Income Taxes	Income Taxes The Company accounts for income taxes using the liability method, whereby deferred tax asset and liability account balances are determined based on differences between financial reporting and tax basis of assets and liabilities and are measured using the enacted tax rates that will be in effect when the differences are expected to reverse. The Company provides a valuation allowance, if necessary, to reduce deferred tax assets to amounts that are realizable. The Company accounts for uncertain tax positions using a “more-likely-than-not” threshold for recognizing and resolving uncertain tax positions. The evaluation of uncertain tax positions is based on factors including, but not limited to, changes in tax law, the measurement of tax positions taken or expected to be taken in tax returns, the effective settlement of matters subject to audit, new audit activity and changes in facts or circumstances related to a tax position. The Company evaluates these tax positions on an annual basis. The Company also accrues for potential interest and penalties related to unrecognized tax benefits in income tax expense. The Company recognizes the tax benefit of tax positions to the extent that the benefit will more likely than not be realized. The determination as to whether the tax benefit will more likely than not be realized is based upon the technical merits of the tax position as well as consideration of the available facts and circumstances.
Stock-Based Compensation	Stock-Based Compensation The Company recognizes compensation costs resulting from the issuance of stock-based awards to employees and directors as an expense in the consolidated statements of operations over the requisite service period based on a measurement of fair value for each stock award. The awards issued to date have been stock options with service-based vesting periods over two or four years. The Company recognizes compensation costs resulting from the issuance of stock-based awards to non-employees as an expense in the consolidated statements of operations over the service period based on a measurement of fair value for each stock award at each performance date and period end. Prior to the completion of the reverse acquisition, the fair value of the common stock was determined by the Board of Directors after considering a broad range of factors, including the results obtained from an independent third-party valuation, the illiquid nature of an investment in the Company’s Common Stock, the Company’s historical financial performance and financial position, the Company’s future prospects and opportunity for liquidity events, and recent sale and offer prices of Common and Preferred Stock in private transactions negotiated at arm’s length. Subsequent to the completion of the reverse acquisition, the fair value of the Common Stock was obtained from quoted market prices on the OTCQB as provided by OTC Market Groups, Inc. In connection with the public offering in May 2015, the Company’s common stock was approved for listing on the NYSE MKT, where it commenced trading under the symbol “CVRS”. The following assumptions were used to estimate the fair value of stock options granted using the Black-Scholes-Merton option-pricing model (“Black-Scholes Model”): Years ended December 31, 2013 2014 2015 Risk-free interest rate 0.72% to 1.43 1.89% to 2.01% 1.54% to 1.97 Expected term in years 5.75 to 6.25 6.25 6.08 Expected volatility 80 50 50% Expected dividend yield 0 0 0% The risk-free interest rate assumption is based upon observed U.S. government security interest rates with a term that is consistent with the expected term of the Company’s employee stock options. The expected term is based on the average of the vesting period and contractual term of the Company’s options given the lack of historical data available. The Company does not pay a dividend, and is not expected to pay a dividend in the foreseeable future. Due to a lack of a public market for the Company’s Common Stock for an extended period of time, the Company utilized comparable public companies’ volatility rates as a proxy of its expected volatility for purposes of the Black-Scholes Model. Stock-based compensation expense is recorded net of estimated forfeitures and is adjusted periodically for actual forfeitures. The Company uses historical data to estimate forfeiture rates. For the years ended December 31, 2013, 2014 and 2015, forfeitures were estimated to be 4.9%, 6.0% and 5.0%, respectively.
Warrant Liability	Warrant Liability The Company reviews the terms of warrants issued in connection with the applicable accounting guidance and classifies warrants as a long-term liability on the consolidated balance sheets if the warrant may conditionally obligate the Company to transfer assets, including repurchase of the Company’s capital stock, at some point in the future. Warrants to purchase shares of redeemable convertible preferred stock met these criteria and therefore required liability-classification. The Company classifies warrants within stockholders’ equity on the consolidated balance sheets if the warrants are considered to be indexed to the Company’s own capital stock, and otherwise would be recorded in stockholders’ equity. Liability-classified warrants are subject to re-measurement at each balance sheet date, and any change in fair value is recognized as a component of other income (expense) in the consolidated statements of operations. The Company estimated the fair value of these warrants at issuance and each balance sheet date thereafter using the Black-Scholes Model as described in the stock-based compensation section above, based on the estimated market value of the underlying Redeemable Convertible Preferred Stock at the valuation measurement date, the remaining contractual term of the warrant, risk-free interest rates, expected dividends and expected volatility of the price of the underlying redeemable convertible preferred stock. The fair value of the Redeemable Convertible Preferred Stock was determined by the Board of Directors after considering a broad range of factors, including the results obtained from an independent third-party valuation, the illiquid nature of an investment in the Company’s Redeemable Convertible Preferred Stock, the Company’s historical financial performance and financial position, the Company’s future prospects and opportunity for liquidity events, and recent sale and offer prices of Common and Preferred Stock in private transactions negotiated at arm’s length. The Company had warrants outstanding to purchase shares of Series A, D and E Redeemable Convertible Preferred Stock, which converted into warrants to purchase shares of Common Stock at the date of the Acquisition. Prior to the Acquisition, the warrant instruments required mark-to-market accounting which was recorded in the statements of operations based on their fair values determined using the Black-Scholes Model and the fair value of underlying Preferred Stock. The warrant instruments were re-valued for the last time at the date of the Acquisition and reclassified into stockholders’ equity in 2014, and at December 31, 2014 and 2015, the Company did not have a warrant liability.
Related-Party Transactions	Related-Party Transactions On January 21, 2011, the Company entered into a distributor agreement with Philips appointing Philips to be the sole distributor for the promotion and sale of the Company’s CorPath System. The agreement was terminated on August 7, 2014. The Company continues to sell CorPath Systems through Philips on a sale by sale basis under a non-exclusive arrangement under mutually agreeable terms, which may include a continued level of discounted pricing, until such time the Company either executes a new distribution arrangement with Philips or the Company no longer does business with Philips. For the years ended December 31, 2013, 2014 and 2015, the Company recorded revenues of $630, $315 and $125, respectively, from shipments to Philips under the distribution agreement. At December 31, 2014 and 2015, there were no amounts outstanding from Philips, resulting from selling activity under the agreement. As of December 31, 2015, Koninklijke Philips, N.V. ("Philips' Parent"), held approximately 15% of the Company's outstanding Common Stock.
Recent Accounting Pronouncements Not Yet Adopted	Recent Accounting Pronouncements Not Yet Adopted In May 2014, the FASB issued ASU 2014-09—Revenue from Contracts with Customers, which amends FASB Accounting Standards Codification Topic 606. ASU 2014-09 provides a single, comprehensive revenue recognition model for all contracts with customers. This standard contains principles for the determination of the measurement of revenue and the timing of when such revenue is recognized. Revenue recognition will reflect the transfer of goods or services to customers at an amount that is expected to be earned in exchange for those goods or services. ASU 2014-09 was scheduled to be effective for annual reporting periods beginning after December 15, 2016, and early adoption was not permitted. In August 2015, the FASB issued ASU No. 2015-14—Revenue from Contracts with Customers: Deferral of Effective Date, which defers the effective date of ASU 2014-09 by one year. ASU 2014-09 is now effective for annual periods after December 15, 2017 including interim periods within that reporting period. Early adoption is permitted, but not before the original effective date. The Company is currently assessing the impact of this standard to its consolidated financial statements. In August 2014, the FASB issued ASU 2014-15, Disclosure of Uncertainties about an Entity’s Ability to Continue as a Going Concern. The amendments in this update will explicitly require a company’s management to assess an entity’s ability to continue as a going concern, and to provide related footnote disclosures in certain circumstances. The new standard will be effective in the first annual period ending after December 15, 2016. Early adoption is permitted. If this standard had been adopted as of December 31, 2015, the Company believes that it would have concluded there was not substantial doubt about its ability to continue as a going concern. However, the Company faces certain risks and uncertainties, as further described in Note 1, Nature of Operations, that could have affected this analysis. In January 2015, the FASB issued Financial Accounting Standards Update—Simplifying Income Statement Presentation by Eliminating the Concept of Extraordinary Items. Subtopic 225-20, Income Statement—Extraordinary and Unusual Items, previously required that an entity separately classify, present, and disclose extraordinary events and transactions. This update is effective for fiscal years, and interim periods within those fiscal years, beginning after December 15, 2015 and may be applied prospectively or retrospectively to all prior periods presented in the financial statements. Early adoption is permitted provided that the guidance is applied from the beginning of the fiscal year of adoption. The Company does not expect the impact of adoption to be material to its consolidated financial statements. In February 2015, the FASB issued ASU 2015-02, Consolidation (Topic 810) to address financial reporting considerations for the evaluation as to the requirement to consolidate certain legal entities. ASU 2015-02 is effective for fiscal years and for interim periods within those fiscal years beginning after December 15, 2015. The Company does not expect the impact of ASU 2015-02 to be material to its consolidated financial statements. In April 2015, the FASB issued ASU 2015-03, Interest—Imputation of Interest (Subtopic 835-30) as part of the initiative to reduce complexity in accounting standards. The update requires that debt issuance costs related to a recognized debt liability be presented in the balance sheet as a direct deduction from the carrying amount of that debt liability, consistent with debt discounts. ASU 2015-03 is effective for annual periods beginning after December 15, 2015 and for interim periods within those fiscal years. The Company does not expect the impact of ASU 2015-03 to be material to its consolidated financial statements. In July 2015, the FASB issued ASU 2015-11, Inventory (Topic 330): Simplifying the Measurement of Inventory. Under this accounting guidance, inventory will be measured at the lower of cost and net realizable value and other options that currently exist for market value will be eliminated. ASU 2015-11 defines net realizable value as the estimated selling prices in the ordinary course of business, less reasonably predictable costs of completion, disposal, and transportation. No other changes were made to the current guidance on inventory measurement. The guidance is effective for annual reporting periods and interim periods within those annual reporting periods beginning after December 15, 2016. Early adoption is permitted and the prospective transition method should be applied. The Company is currently evaluating the impact of ASU 2015-11 on its consolidated financial statements. In January 2016, the FASB issued ASU 2016-01, Financial Instruments - Overall (Subtopic 825-10): Recognition and Measurement of Financial Assets and Financial Liabilities. The update addresses certain aspects of recognition, measurement, presentation and disclosure of financial instruments. ASU 2016-01 is effective for fiscal years, and interim periods within those years, beginning after December 15, 2017. Early adoption is permitted only for certain portions of the ASU related to financial liabilities. The Company is currently evaluating the impact of this standard on its consolidated financial statements. In February 2016, the FASB issued ASU 2016-02, Leases (Topic 842), which amends leasing accounting requirements. The new standard requires lessee recognition on the balance sheet of a right-of-use asset and a lease liability, initially measured at the present value of the lease payments. It further requires recognition in the income statement of a single lease cost, calculated so that the cost of the lease is allocated over the lease term on a generally straight-line basis. Finally, it requires classification of all cash payments within operating activities in the statement of cash flows. It is effective for fiscal years commencing after December 15, 2018 and early adoption is permitted. The Company is currently evaluating the impact of this standard on its consolidated financial statements.

Significant Accounting Polici26

Significant Accounting Policies (Tables)	12 Months Ended
	Dec. 31, 2015
Accounting Policies [Abstract]
Summary of Available-for-Sale Securities	The following table summarizes available-for-sale securities held at December 31, 2015: Description Amortized Cost Unrealized Gain Unrealized Loss Fair Value December 31, 2015 U.S. government treasuries $ 15,885 $ 1 $ (10 ) $ 15,876 Certificates of deposit 4,653 — (5 ) 4,648 Total $ 20,538 $ 1 $ (15 ) $ 20,524
Schedule of Assets Measured at Fair Value on Recurring Basis	The following table sets forth the Company’s assets that are measured at fair value on a recurring basis as of December 31, 2015: Fair value measurement category Description Total Quoted prices in active markets Significant other observable inputs Significant unobservable inputs December 31, 2015: Assets: Cash equivalents $ 6,356 $ 6,107 $ 249 $ — Marketable securities: U.S. government treasuries 15,876 15,876 — — Certificates of deposit 4,648 — 4,648 — Total assets $ 26,880 $ 21,983 $ 4,897 $ —
Schedule of Concentration of Customers	The Company had the following customers that accounted for greater than 10% of its revenues for the year ended December 31, 2014 and 2015, respectively: For the Year ended December 31, 2014 2015 Customer Percent of Revenues Percent of Revenues A 27 % — B 12 % — C 11 % — D 11 % — E 10 % — F — 13 % G — 11 % H — 10 %
Schedule rollforward of the warranty liability	A roll-forward of the Company’s warranty liability is as follows: Balance at December 31, 2013 $ 29 Provision for warranty obligations 96 Settlements (64 ) Balance at December 31, 2014 61 Provisions for warranty obligations 58 Settlements (51 ) Balance at December 31, 2015 $ 68
Schedule of assumptions used to estimate the fair value of stock options	The following assumptions were used to estimate the fair value of stock options granted using the Black-Scholes-Merton option-pricing model (“Black-Scholes Model”): Years ended December 31, 2013 2014 2015 Risk-free interest rate 0.72% to 1.43 1.89% to 2.01% 1.54% to 1.97 Expected term in years 5.75 to 6.25 6.25 6.08 Expected volatility 80 50 50% Expected dividend yield 0 0 0%

Inventories (Tables)

Inventories (Tables)	12 Months Ended
	Dec. 31, 2015
Inventory Disclosure [Abstract]
Schedule of Inventories alued at the lower of cost or market using the FIFO method	The Company’s inventories are valued at the lower of cost or market using the FIFO method and consist of the following: December 31, 2014 2015 Raw materials $ 737 $ 483 Work in progress 198 79 Finished goods 584 767 $ 1,519 $ 1,329

Property and Equipment (Tables)

Property and Equipment (Tables)	12 Months Ended
	Dec. 31, 2015
Property, Plant and Equipment [Abstract]
Summary of Property and Equipment, Net	Property and equipment are stated at cost and are being depreciated using the straight-line basis over the assets’ estimated useful lives. Depreciation and amortization expense was $607, $622 and $706 for the fiscal years 2013, 2014 and 2015, respectively. Property and equipment consist of the following: December 31, 2014 2015 Machinery and equipment $ 334 $ 441 Computer equipment 273 286 Office furniture and equipment 355 360 Leasehold improvements 67 70 Vendor tooling 711 715 Software 490 498 Demonstration equipment 633 717 Field equipment 588 1,004 Construction in progress — 126 3,451 4,217 Less accumulated depreciation and amortization (2,167 ) (2,835 ) Property and equipment, net $ 1,284 $ 1,382

Accrued Expenses (Tables)

Accrued Expenses (Tables)	12 Months Ended
	Dec. 31, 2015
Payables and Accruals [Abstract]
Schedule of Accrued Expenses	Accrued expenses consist of the following: 2014 2015 Payroll and benefits $ 185 $ 79 Professional and consultant fees 496 444 Travel expenses 57 113 Product development costs 62 44 Commissions 85 187 Warranty 61 68 Interest 48 71 Other 143 193 $ 1,137 $ 1,199 _______________________ Certain items classified as "Other" in the prior year, travel expense and interest, were changed to conform with the current year presentation.

Long-Term Debt (Tables)

Long-Term Debt (Tables)	12 Months Ended
	Dec. 31, 2015
Debt Disclosure [Abstract]
Assumption for the valuation of its warrants issued	The Company used the following assumptions for the valuation of its warrants issued on the following dates: June 11, 2014 December 31, 2014 Risk-free interest rate 2.5 % 2.17 % Dividend yield 0.0 % 0.0 % Expected volatility 50.0 % 50.0 % Expected term (years) 10.00 9.44
Schedule of future principal payments under the borrowing arrangement	Future principal payments under the borrowing arrangement as of December 31, 2015 are as follows: Year ending December 31: 2016 $ 4,373 2017 3,605 $ 7,978

Income Taxes (Tables)

Income Taxes (Tables)	12 Months Ended
	Dec. 31, 2015
Income Tax Disclosure [Abstract]
Reconciliation of effective income tax rate to the statutory federal income tax rate	The Company’s effective income tax rate differs from the statutory federal income tax rate as follows: Years Ended December 31, 2013 2014 2015 Statutory U.S. federal rate 34.0 % 34.0 % 34.0 % State income tax 4.7 1.7 3.7 Permanent items 0.6 (3.8 ) (0.4 ) Change in taxing status in Massachusetts to a manufacturer — (4.9 ) — Other (0.8 ) (0.7 ) (0.5 ) Change in state tax rate — — 0.7 Federal R&D credits 2.0 1.2 1.3 State R&D and other credits 0.5 0.7 0.5 Change in valuation allowance (41.0 ) (28.2 ) (39.3 ) Total expense (benefit) — % — % — %
Schedule of Deferred Income Tax Assets and Liabilities	Deferred income taxes reflect the net tax effects of temporary differences between the carrying amounts of assets and liabilities for financial reporting purposes and the amounts used for income tax purposes. Significant components of the Company’s deferred tax assets and the related valuation allowance were as follows: December 31, 2014 2015 Deferred income tax assets: Operating loss carryforwards $ 20,178 $ 30,832 Start-up expenditures 2,807 2,711 Property and equipment 46 28 Intangible assets 2,589 — Stock-based compensation expense 738 788 Research and development credit carryforwards 1,216 1,746 Accrued expenses and other 307 482 Total deferred income tax assets 27,881 36,587 Valuation allowance (27,881 ) (36,587 ) Net deferred income tax assets $ — $ —

Stock-based Compensation (Table

Stock-based Compensation (Tables)	12 Months Ended
	Dec. 31, 2015
Disclosure of Compensation Related Costs, Share-based Payments [Abstract]
Summary of the activity under the stock option plans	A summary of the activity under the Company’s stock option plans is as follows. Such information has been retrospectively adjusted to give effect to the exchange of stock options that occurred upon the Acquisition. Options Weighted- Average Exercise Price Weighted- Average Remaining Contractual Term (Years) Aggregate Intrinsic Value Outstanding at December 31, 2014 8,678,017 $ 0.64 6.30 $ 31,359 Granted 1,454,486 $ 3.51 Exercised (347,392 ) $ 0.28 Cancelled (1,006,608 ) $ 0.80 Outstanding at December 31, 2015 8,778,503 $ 1.11 5.98 $ 18,876 Exercisable at December 31, 2015 6,673,104 $ 0.63 5.01 $ 17,220 Vested and expected to vest at December 31, 2015 8,673,233 $ 1.09 5.95 $ 18,813
Schedule of Stock-Based Compensation Expense	Stock-based compensation expense was allocated based on the employees’ function as follows: Years ended December 31, 2013 2014 2015 Research and development $ 59 $ 95 $ 74 Selling, general and administrative 270 282 431 $ 329 $ 377 $ 505

Warrants to Purchase Common S33

Warrants to Purchase Common Stock (Tables)	12 Months Ended
	Dec. 31, 2015
Text Block [Abstract]
Schedule of Rollforward of Warrant Liability	A roll forward of the warrant liability is as follows: Balance at December 31, 2013 $ 3,152 Issuance of warrants in connection with lending arrangement 230 Revaluation of warrants 2,421 Reclassification of warrant liability to stockholders’ equity (5,803 ) Balance at December 31, 2014 $ —
Schedule of assumptions for the valuation of its warrant liability	The Company used the following assumptions for the valuation of its warrant liability: August 12, 2014 Risk-free interest rate 1.025 % Dividend yield 0.0 % Expected volatility 50.0 % Expected term (years) 3.5
Schedule of warrants outstanding	The Company has following warrants outstanding at December 31, 2015: Exercise Price Date of Expiration Number of Warrants $1.06 October 11, 2017 4,728,191 $0.76 May 31, 2017 124,160 $1.41 May 28, 2020 355,028 5,207,379

Commitments and Contingencies (

Commitments and Contingencies (Tables)	12 Months Ended
	Dec. 31, 2015
Commitments and Contingencies Disclosure [Abstract]
Schedule of future minimum lease payments	At December 31, 2015, the Company’s future minimum lease payments are indicated below: Year ending December 31: Total Lease Payments 2016 $ 573 2017 586 2018 49 Total $ 1,208

Net Loss per Share (Tables)

Net Loss per Share (Tables)	12 Months Ended
	Dec. 31, 2015
Earnings Per Share [Abstract]
Schedule of Securities Excluded from Computation of Net Loss per Share	The following common stock equivalents were excluded from the calculation of diluted net loss per share for the periods indicated because including them would have had an anti-dilutive effect: Years Ended December 31, 2013 2014 2015 Options to purchase Common Stock 8,548,357 8,678,017 8,778,503 Warrants to purchase Common Stock 4,852,351 5,207,379 5,207,379 Total 13,400,708 13,885,396 13,985,882

Selected Quarterly Financial 36

Selected Quarterly Financial Data (Tables)	12 Months Ended
	Dec. 31, 2015
Quarterly Financial Information Disclosure [Abstract]
Summary of quarterly financial data	The following table presents unaudited operating results for each of the Company’s quarters in the years ended December 31, 2015 and 2014: Fiscal Year 2015 Quarters First Second Third Fourth Year Revenue $ 776 $ 909 $ 212 $ 832 $ 2,729 Cost of revenue 801 941 722 1 ,260 3 ,724 Gross profit (loss) (25 ) (32 ) (510 ) (428 ) (995 ) Operating expenses 6 ,747 6 ,839 6 ,148 6 ,442 26,176 Operating loss (6,772 ) (6,871 ) (6,658 ) (6,870 ) (27,171 ) Total other expense, net (397 ) (432 ) (404 ) (359 ) (1,592 ) Net loss $ (7,169 ) $ (7,303 ) $ (7,062 ) $ (7,229 ) $ (28,763 ) Net loss per share - basic and diluted $ (0.07 ) $ (0.07 ) $ (0.06 ) $ (0.06 ) $ (0.25 ) Fiscal Year 2014 Quarters First Second Third Fourth Year Revenue $ 730 $ 1,077 $ 554 $ 622 $ 2,983 Cost of revenue 1 ,383 1 ,058 793 1 ,670 (1) 4 ,904 Gross profit (loss) (653 ) 19 (239 ) (1,048 ) (1,921 ) Operating expenses 4 ,949 4 ,388 5 ,148 5 ,299 19,784 Operating loss (5,602 ) (4,369 ) (5,387 ) (6,347 ) (21,705 ) Total other income (expense) 1 ,768 (1,341 ) (3,062 ) (201 ) (2,836 ) Net loss $ (3,834 ) $ (5,710 ) $ (8,449 ) $ (6,548 ) $ (24,541 ) Net loss per share - basic and diluted $ (0.05 ) $ (0.08 ) $ (0.10 ) $ (0.06 ) $ (0.29 ) ___________________ (1)

Nature of Operations - additona

Nature of Operations - additonal information (Detail) - USD ($) $ / shares in Units, $ in Millions	May. 28, 2015	Dec. 31, 2015
Accounting Policies [Abstract]
Share price (in dollars per share)	$ 3.80
Issuance of common stock in connection with public offering, shares	12,650,000
Cash, cash equivalents and marketable securities		$ 4,266.6
Borrowings outstanding		797.8
Borrowings outstanding, current		437.3
Working capital		$ 3,798.8

Significant Accounting Polici38

Significant Accounting Policies - Additional Information (Detail) $ in Thousands	3 Months Ended								12 Months Ended
	Dec. 31, 2015USD ($)	Sep. 30, 2015USD ($)	Jun. 30, 2015USD ($)	Mar. 31, 2015USD ($)	Dec. 31, 2014USD ($)	Sep. 30, 2014USD ($)	Jun. 30, 2014USD ($)	Mar. 31, 2014USD ($)	Dec. 31, 2015USD ($)	Dec. 31, 2014USD ($)	Dec. 31, 2013USD ($)
Significant Accounting Policies [Line Items]
Number of segments									1
Number of certificate of deposit	13								13
Available-for-sale Securities, Fair Value	$ 20,524								$ 20,524
Warranty period of systems sold									1 year
Credit provided to eligible customers	1								$ 1
Medical device excise tax expense									$ 34	$ 40	$ 29
Estimated forfeitures rates									5.00%	6.00%	4.90%
Revenue	832	$ 212	$ 909	$ 776	$ 622	$ 554	$ 1,077	$ 730	$ 2,729	$ 2,983	$ 896
Fair value long-term debt	$ 7,715				$ 9,111				7,715	9,111
Philips [Member]
Significant Accounting Policies [Line Items]
Revenue									$ 125	315	630
Ownership interest	15.00%								15.00%
Americas [Member]
Significant Accounting Policies [Line Items]
Revenue									$ 2,684	2,068	896
Dubai and Israel [Member]
Significant Accounting Policies [Line Items]
Revenue									45	915	$ 0
Not-For-Profit Subsidiary [Member]
Significant Accounting Policies [Line Items]
Recognized expenses									$ 386	$ 18
Maximum [Member] | Stock Option Plans [Member]
Significant Accounting Policies [Line Items]
Vesting period of stock options										4 years
Minimum [Member] | Stock Option Plans [Member]
Significant Accounting Policies [Line Items]
Vesting period of stock options									2 years
Sales Revenue, Net [Member] | Customer Concentration Risk [Member] | Customer One [Member]
Significant Accounting Policies [Line Items]
Concentration percentage											71.00%
Sales Revenue, Net [Member] | Customer Concentration Risk [Member] | Maximum [Member]
Significant Accounting Policies [Line Items]
Concentration percentage											10.00%
Sales Revenue, Net [Member] | Customer Concentration Risk [Member] | Minimum [Member]
Significant Accounting Policies [Line Items]
Concentration percentage									10.00%	10.00%
Accounts Receivable [Member] | Customer Concentration Risk [Member] | Customer One [Member]
Significant Accounting Policies [Line Items]
Concentration percentage									38.00%	25.00%
Accounts Receivable [Member] | Customer Concentration Risk [Member] | Customer B [Member]
Significant Accounting Policies [Line Items]
Concentration percentage										27.00%
Accounts Receivable [Member] | Customer Concentration Risk [Member] | Customer F [Member]
Significant Accounting Policies [Line Items]
Concentration percentage									38.00%

Significant Accounting Polici39

Significant Accounting Policies - Summary of Available-for-Sale Securities (Detail) $ in Thousands	Dec. 31, 2015USD ($)
Schedule of Available-for-sale Securities [Line Items]
Available-for-sale Securities, Amortized Cost	$ 20,538
Available-for-sale Securities, Gross Unrealized Gains	1
Available-for-sale Securities, Gross Unrealized Losses	(15)
Available-for-sale Securities, Fair Value	20,524
Certificates of Deposit [Member]
Schedule of Available-for-sale Securities [Line Items]
Available-for-sale Securities, Amortized Cost	4,653
Available-for-sale Securities, Gross Unrealized Losses	(5)
Available-for-sale Securities, Fair Value	4,648
US Government Treasuries [Member]
Schedule of Available-for-sale Securities [Line Items]
Available-for-sale Securities, Amortized Cost	15,885
Available-for-sale Securities, Gross Unrealized Gains	1
Available-for-sale Securities, Gross Unrealized Losses	(10)
Available-for-sale Securities, Fair Value	$ 15,876

Significant Accounting Polici40

Significant Accounting Policies - Schedule of Assets Measured at Fair Value on Recurring Basis (Detail) $ in Thousands	Dec. 31, 2015USD ($)
Assets:
Marketable securities	$ 20,524
Certificates of Deposit [Member]
Assets:
Marketable securities	4,648
Recurring [Member]
Assets:
Cash equivalents	6,356
Total assets	26,880
Recurring [Member] | Fair Value, Inputs, Level 1 [Member]
Assets:
Cash equivalents	6,107
Total assets	21,983
Recurring [Member] | Fair Value, Inputs, Level 2 [Member]
Assets:
Cash equivalents	249
Total assets	4,897
Recurring [Member] | US Government Treasuries [Member]
Assets:
Marketable securities	15,876
Recurring [Member] | US Government Treasuries [Member] | Fair Value, Inputs, Level 1 [Member]
Assets:
Marketable securities	15,885
Recurring [Member] | Certificates of Deposit [Member]
Assets:
Marketable securities	4,648
Recurring [Member] | Certificates of Deposit [Member] | Fair Value, Inputs, Level 2 [Member]
Assets:
Marketable securities	$ 4,648

Significant Accounting Polici41

Significant Accounting Policies - Schedule of Concentration of Customers (Detail) - Sales Revenue, Net [Member]	12 Months Ended
	Dec. 31, 2015	Dec. 31, 2014
Customer A [Member]
Concentration Risk [Line Items]
Concentration percentage		27.00%
Customer B [Member]
Concentration Risk [Line Items]
Concentration percentage		12.00%
Customer C [Member]
Concentration Risk [Line Items]
Concentration percentage		11.00%
Customer D [Member]
Concentration Risk [Line Items]
Concentration percentage		11.00%
Customer E [Member]
Concentration Risk [Line Items]
Concentration percentage		10.00%
Customer F [Member]
Concentration Risk [Line Items]
Concentration percentage	13.00%
Customer G [Member]
Concentration Risk [Line Items]
Concentration percentage	11.00%
Customer H [Member]
Concentration Risk [Line Items]
Concentration percentage	10.00%

Significant Accounting Polici42

Significant Accounting Policies - Roll-forward of Warranty Liability (Detail) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2015	Dec. 31, 2014
Accounting Policies [Abstract]
Beginning balance, Product warrant liability	$ 61	$ 29
Provision for warranty obligation	58	96
Settlements	(51)	(64)
Ending balance, Product warrant liability	$ 68	$ 61

Significant Accounting Polici43

Significant Accounting Policies - Property and Equipment, Estimated Useful Lives (Detail)	12 Months Ended
	Dec. 31, 2015
Machinery and Equipment [Member]
Property, Plant and Equipment [Line Items]
Estimated useful lives	5 years
Computer Equipment [Member]
Property, Plant and Equipment [Line Items]
Estimated useful lives	3 years
Office Furniture and Equipment [Member]
Property, Plant and Equipment [Line Items]
Estimated useful lives	5 years
Vendor Tooling [Member] | Minimum [Member]
Property, Plant and Equipment [Line Items]
Estimated useful lives	1 year 6 months
Vendor Tooling [Member] | Maximum [Member]
Property, Plant and Equipment [Line Items]
Estimated useful lives	3 years
Software [Member]
Property, Plant and Equipment [Line Items]
Estimated useful lives	4 years
Demonstration Equipment [Member]
Property, Plant and Equipment [Line Items]
Estimated useful lives	3 years
Field Equipment [Member]
Property, Plant and Equipment [Line Items]
Estimated useful lives	3 years

Significant Accounting Polici44

Significant Accounting Policies - Assumptions Used to Estimate Fair Value of Stock Options Granted Using Black-Scholes-Merton Option Pricing Model (Detail) - Stock Option Plans [Member]	12 Months Ended
	Dec. 31, 2015	Dec. 31, 2014	Dec. 31, 2013
Fair Value Measurement [Line Items]
Expected term in years	6 years 29 days	6 years 3 months
Expected volatility	50.00%	50.00%	80.00%
Expected dividend yield	0.00%	0.00%	0.00%
Minimum [Member]
Fair Value Measurement [Line Items]
Risk-free interest rate	1.54%	1.89%	0.72%
Expected term in years			5 years 9 months
Maximum [Member]
Fair Value Measurement [Line Items]
Risk-free interest rate	1.97%	2.01%	1.43%
Expected term in years			6 years 3 months

Inventories - Schedule of Inven

Inventories - Schedule of Inventories Valued under FIFO Method (Detail) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2014	Dec. 31, 2015
Inventory Disclosure [Abstract]
Raw material	$ 737	$ 483
Work in progress	198	79
Finished goods	584	767
Inventories, net	1,519	$ 1,329
Inventory reclassification	$ 124

Property and Equipment - Additi

Property and Equipment - Additional Information (Detail) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2015	Dec. 31, 2014	Dec. 31, 2013
Property, Plant and Equipment [Abstract]
Property plant and equipment depreciation expense	$ 706	$ 622	$ 607

Property and Equipment - Summar

Property and Equipment - Summary of Property and Equipment, Net (Detail) - USD ($) $ in Thousands	Dec. 31, 2015	Dec. 31, 2014
Property, Plant and Equipment [Line Items]
Property and equipment, Gross	$ 4,217	$ 3,451
Less accumulated depreciation and amortization	(2,835)	(2,167)
Property and equipment, net	1,382	1,284
Machinery and Equipment [Member]
Property, Plant and Equipment [Line Items]
Property and equipment, Gross	441	334
Computer Equipment [Member]
Property, Plant and Equipment [Line Items]
Property and equipment, Gross	286	273
Office Furniture and Equipment [Member]
Property, Plant and Equipment [Line Items]
Property and equipment, Gross	360	355
Leasehold Improvements [Member]
Property, Plant and Equipment [Line Items]
Property and equipment, Gross	70	67
Vendor Tooling [Member]
Property, Plant and Equipment [Line Items]
Property and equipment, Gross	715	711
Software [Member]
Property, Plant and Equipment [Line Items]
Property and equipment, Gross	498	490
Demonstration Equipment [Member]
Property, Plant and Equipment [Line Items]
Property and equipment, Gross	717	633
Field Equipment [Member]
Property, Plant and Equipment [Line Items]
Property and equipment, Gross	1,004	$ 588
Construction in Progress [Member]
Property, Plant and Equipment [Line Items]
Property and equipment, Gross	$ 126

Notes Receivable - Additional I

Notes Receivable - Additional Information (Detail) - USD ($) $ in Thousands	Jun. 14, 2010	Feb. 29, 2016	Dec. 31, 2015	Dec. 31, 2014
Accounts, Notes, Loans and Financing Receivable [Line Items]
Issuance of notes receivable due from stockholder	$ 145
Notes receivable			$ 136	$ 136
Repayment of notes receivable		$ 65
Notes Receivable [Member]
Accounts, Notes, Loans and Financing Receivable [Line Items]
Impairment cost for notes receivable			$ 0	$ 0

Accrued Expenses - Schedule of

Accrued Expenses - Schedule of Accrued Expenses (Detail) - USD ($) $ in Thousands	Dec. 31, 2015	Dec. 31, 2014
Payables and Accruals [Abstract]
Payroll and benefits	$ 79	$ 185
Professional and consultant fees	444	496
Travel expenses	113	57
Product development costs	44	62
Commissions	187	85
Warranty	68	61
Interest	71	48
Other	193	143
Accrued expenses	$ 1,199	$ 1,137

Long-Term Debt - Additional Inf

Long-Term Debt - Additional Information (Detail) - USD ($)	Jun. 11, 2014	Dec. 31, 2015	Dec. 31, 2014
Line of Credit Facility [Line Items]
Number of shares callable by warrants outstanding		5,207,379
Secured Promissory Notes [Member]
Line of Credit Facility [Line Items]
Additional interest payment		$ 150,000
Net borrowings outstanding		7,715,000
Unamortized discount of debt		$ 414,000
Promissory Note 1 [Member]
Line of Credit Facility [Line Items]
Available borrowing under Loan and Security Agreement	$ 10,000,000
Amount of each separate note	$ 5,000,000
Note issuance date	Jun. 11, 2014
Frequency of debt payments	Monthly
Term of debt payments	27 months
Date of first required payment	Jul. 1, 2015
Interest rate, minimum	11.25%
Effective interest rate		11.50%
Interest rate, description of maximum	11.25% plus the Wall Street Journal Prime Rate, less 3.25%
Spread on variable rate	(3.25%)
Additional interest payment	$ 125,000
Due date of additional interest payment	Oct. 1, 2017
Number of shares callable by warrants outstanding	177,514
Exercise price of warrant	$ 1.41
Fair value of the warrant issued	$ 230,000
Promissory Note 2 [Member]
Line of Credit Facility [Line Items]
Amount of each separate note			$ 5,000,000
Frequency of debt payments			Monthly
Term of debt payments			27 months
Date of first required payment			Jul. 1, 2015
Interest rate, minimum			9.95%
Effective interest rate		10.20%
Interest rate, description of maximum			9.95% plus the Wall Street Journal Prime Rate, less 3.25%
Spread on variable rate			(3.25%)
Additional interest payment			$ 125,000
Due date of additional interest payment			Oct. 1, 2017
Number of shares callable by warrants outstanding			177,514
Exercise price of warrant			$ 1.41
Fair value of the warrant issued			$ 619,000

Long-Term Debt - Assumption for

Long-Term Debt - Assumption for the Valuation of Warrants Issued (Detail) - Warrant [Member]	Aug. 12, 2014	Jun. 11, 2014	Dec. 31, 2014
Fair Value Measurements, Recurring and Nonrecurring, Valuation Techniques [Line Items]
Risk-free interest rate	1.025%	2.50%	2.17%
Dividend yield	0.00%	0.00%	0.00%
Expected volatility	50.00%	50.00%	50.00%
Expected term (years)	3 years 6 months	10 years	9 years 5 months 9 days

Long-Term Debt - Schedule of Fu

Long-Term Debt - Schedule of Future Principal Payments Under Borrowing Arrangement (Detail) $ in Thousands	Dec. 31, 2015USD ($)
Debt Disclosure [Abstract]
2,016	$ 4,373
2,017	3,605
Long term debt	$ 7,978

Income Taxes - Additional Infor

Income Taxes - Additional Information (Detail) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2015	Dec. 31, 2014
Income Tax Examination [Line Items]
Change in valuation allowance	$ 8,706	$ 6,912
State and Local Jurisdiction [Member]
Income Tax Examination [Line Items]
Net operating loss carryforwards	56,585
Internal Revenue Service (IRS) [Member]
Income Tax Examination [Line Items]
Net operating loss carryforwards	$ 82,989

Income Taxes - Reconciliation o

Income Taxes - Reconciliation of Effective Income Tax rate (Detail)	12 Months Ended
	Dec. 31, 2015	Dec. 31, 2014	Dec. 31, 2013
Income Tax Disclosure [Abstract]
Statutory U.S. federal rate	34.00%	34.00%	34.00%
State income tax	3.70%	1.70%	4.70%
Permanent items	(0.40%)	(3.80%)	0.60%
Change in taxing status in Massachusetts to a manufacturer		(4.90%)
Other	(0.50%)	(0.70%)	(0.80%)
Change in state tax rate	0.70%
Federal R&D credits	1.30%	1.20%	2.00%
State R&D and other credits	0.50%	0.70%	0.50%
Change in valuation allowance	(39.30%)	(28.20%)	(41.00%)
Total expense (benefit)

Income Taxes - Schedule of Defe

Income Taxes - Schedule of Deferred Income Tax Assets and Liabilities (Detail) - USD ($) $ in Thousands	Dec. 31, 2015	Dec. 31, 2014
Deferred income tax assets:
Operating loss carryforwards	$ 30,832	$ 20,178
Start-up expenditures	2,711	2,807
Property and equipment	28	46
Intangible assets		2,589
Stock-based compensation expense	788	738
Research and development credit carryforwards	1,746	1,216
Accrued expenses and other	482	307
Total deferred income tax assets	36,587	27,881
Valuation allowance	$ (36,587)	$ (27,881)
Net deferred income tax assets

Stockholders' Equity - Addition

Stockholders' Equity - Additional Information (Detail)	Dec. 31, 2015shares
Equity [Abstract]
Common stock reserved for future issuance	23,569,951
Common stock reserved for exercise of warrants	5,207,379
Stock options available for grant	9,584,069
Options outstanding, ending balance	8,778,503

Stock-Based Compensation - Addi

Stock-Based Compensation - Additional Information (Detail) - USD ($)	12 Months Ended
	Dec. 31, 2015	Dec. 31, 2014	Dec. 31, 2013	Apr. 30, 2015	Apr. 29, 2015
Stock Option Plans [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Weighted average grant date fair value options	$ 1.80	$ .16	$ .24
Unrecognized stock-based compensation	$ 2,415
Period stock-based compensation to be recognized	3 years 4 months 17 days
Total intrinsic value of options exercised	$ 852
2014 Stock Award Plan [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Number of shares authorized under plan				18,661,856	9,035,016

Stock-Based Compensation - Summ

Stock-Based Compensation - Summary of the Activity Under the Company's Stock Option Plans (Detail) - USD ($) $ / shares in Units, $ in Thousands	12 Months Ended
	Dec. 31, 2015	Dec. 31, 2014
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Options outstanding, ending balance	8,778,503
Stock Option Plans [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Options outstanding, beginning balance	8,678,017
Options, granted	1,454,486
Options, exercised	(347,392)
Options, cancelled	(1,006,608)
Options outstanding, ending balance		8,678,017
Options, exercisable	6,673,104
Options, vested and expected to vest	8,673,233
Weighted-Average Exercise Price
Options outstanding, beginning balance	$ .64
Granted	3.51
Exercised	0.28
Cancelled	0.80
Options outstanding, ending balance	1.11	$ .64
Options exercisable	.63
Options vested and expected to vest	$ 1.09
Weighted-Average Remaining Contractual Term in Years, Options outstanding	5 years 11 months 23 days	6 years 3 months 19 days
Weighted-Average Remaining Contractual Term in Years, Options exercisable	5 years 4 days
Weighted-Average Remaining Contractual Term in Years, Options vested and expected to vest	5 years 11 months 12 days
Aggregate Intrinsic Value, Options outstanding	$ 18,876	$ 31,359
Aggregate Intrinsic Value, Options exercisable	17,220
Aggregate Intrinsic Value, Options vested and expected to vest	$ 18,813

Stock-Based Compensation - Sche

Stock-Based Compensation - Schedule of Stock-Based Compensation Expense (Detail) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2015	Dec. 31, 2014	Dec. 31, 2013
Share-based Compensation Arrangement by Share-based Payment Award, Compensation Cost [Line Items]
Stock-based compensation expense	$ 505	$ 377	$ 329
Research and Development Expense [Member]
Share-based Compensation Arrangement by Share-based Payment Award, Compensation Cost [Line Items]
Stock-based compensation expense	74	95	59
Selling General And Administrative Expense [Member]
Share-based Compensation Arrangement by Share-based Payment Award, Compensation Cost [Line Items]
Stock-based compensation expense	$ 431	$ 282	$ 270

Warrants to Purchase Common S60

Warrants to Purchase Common Stock - Additional Information (Detail)	12 Months Ended
	Dec. 31, 2014$ / sharesshares
Equity [Abstract]
Number of shares to be converted by warrant pre-exchange | shares	201,178
Average exercise price | $ / shares	$ 26.63
Number of shares to be converted by warrant post-exchange | shares	5,029,865
Common stock average price per share | $ / shares	$ 1.07

Warrants to Purchase Common S61

Warrants to Purchase Common Stock - Rollforward of Warrant Liability (Detail) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2015	Dec. 31, 2014	Dec. 31, 2013
Class of Warrant or Right [Line Items]
Revaluation of warrants		$ (2,421)	$ (171)
Reclassification of warrant liability to stockholders' equity		(5,803)
Warrant [Member]
Class of Warrant or Right [Line Items]
Beginning balance		3,152
Issuance of warrants in connection with lending arrangement		230
Revaluation of warrants		2,421
Reclassification of warrant liability to stockholders' equity		$ (5,803)
Ending balance			$ 3,152

Warrants to Purchase Common S62

Warrants to Purchase Common Stock - Schedule of Assumptions in Revaluation of Outstanding Warrants (Detail) - Warrant [Member]	Aug. 12, 2014	Jun. 11, 2014	Dec. 31, 2014
Class of Warrant or Right [Line Items]
Risk-free interest rate	1.025%	2.50%	2.17%
Dividend yield	0.00%	0.00%	0.00%
Expected volatility	50.00%	50.00%	50.00%
Expected term (years)	3 years 6 months	10 years	9 years 5 months 9 days

Warrants to Purchase Common S63

Warrants to Purchase Common Stock - Schedule of Warrants Outstanding (Detail)	12 Months Ended
	Dec. 31, 2015$ / sharesshares
Class of Warrant or Right [Line Items]
Number of Warrants	5,207,379
October 11, 2017 [Member]
Class of Warrant or Right [Line Items]
Exercise Price | $ / shares	$ 1.06
Date of Expiration	Oct. 11, 2017
Number of Warrants	4,728,191
May 31, 2017 [Member]
Class of Warrant or Right [Line Items]
Exercise Price | $ / shares	$ .76
Date of Expiration	May 31, 2017
Number of Warrants	124,160
May 28, 2020 [Member]
Class of Warrant or Right [Line Items]
Exercise Price | $ / shares	$ 1.41
Date of Expiration	May 28, 2020
Number of Warrants	355,028

Commitments and Contingencies -

Commitments and Contingencies - Additional Information (Detail)	12 Months Ended
	Dec. 31, 2015USD ($)ft²	Dec. 31, 2014USD ($)	Dec. 31, 2013USD ($)
Commitments And Contingencies Disclosure [Line Items]
Office and manufacturing lease (square footage) | ft²	26,402
Operating lease expiration date	Jan. 31, 2018
Security deposit	$ 178
Operating leases expiration year	2,018
Rent expense	$ 574	$ 577	$ 584
Prepaid Expenses and Other Assets [Member]
Commitments And Contingencies Disclosure [Line Items]
Security deposit	45
Minimum [Member]
Commitments And Contingencies Disclosure [Line Items]
Security deposit	$ 134

Commitments and Contingencies65

Commitments and Contingencies - Schedule of Future Minimum Lease Payments (Detail) $ in Thousands	Dec. 31, 2015USD ($)
Commitments and Contingencies Disclosure [Abstract]
2,016	$ 573
2,017	586
2,018	49
Total	$ 1,208

Net Loss per Share - Schedule o

Net Loss per Share - Schedule of Securities Excluded from Computation of Net Loss per Share (Detail) - shares	12 Months Ended
	Dec. 31, 2015	Dec. 31, 2014	Dec. 31, 2013
Antidilutive Securities Excluded from Computation of Earnings Per Share [Line Items]
Number of anti-dilutive securities	13,985,882	13,885,396	13,400,708
Stock Option Plans [Member]
Antidilutive Securities Excluded from Computation of Earnings Per Share [Line Items]
Number of anti-dilutive securities	8,778,503	8,678,017	8,548,357
Warrant [Member]
Antidilutive Securities Excluded from Computation of Earnings Per Share [Line Items]
Number of anti-dilutive securities	5,207,379	5,207,379	4,852,351

Restructuring Charge - Addition

Restructuring Charge - Additional Information (Detail) $ in Thousands	Dec. 31, 2014USD ($)
Restructuring and Related Activities [Abstract]
Restructuring charges - severance and related costs	$ 175

Selected Quarterly Financial 68

Selected Quarterly Financial Data - Additional Information (Detail) - USD ($) $ in Thousands

3 Months Ended

12 Months Ended

Dec. 31, 2015

Sep. 30, 2015

Jun. 30, 2015

Mar. 31, 2015

Dec. 31, 2014

Sep. 30, 2014

Jun. 30, 2014

Mar. 31, 2014

Dec. 31, 2015

Dec. 31, 2014

Dec. 31, 2013

Cost of revenue

$ 1,260

$ 722

$ 941

$ 801

$ 1,670

[1]

$ 793

$ 1,058

$ 1,383

$ 3,724

$ 4,904

$ 2,430

Adjustment For Error Correction - Inventory [Member]

Cost of revenue

$ 536

[1]

Includes $536 from the correction of an immaterial error related to inventory overhead costs that were overstated in the 2013 consolidated financial statements.

Selected Quarterly Financial 69

Selected Quarterly Financial Data (Detail) - USD ($) $ / shares in Units, $ in Thousands	3 Months Ended									12 Months Ended
	Dec. 31, 2015	Sep. 30, 2015	Jun. 30, 2015	Mar. 31, 2015	Dec. 31, 2014		Sep. 30, 2014	Jun. 30, 2014	Mar. 31, 2014	Dec. 31, 2015	Dec. 31, 2014	Dec. 31, 2013
Quarterly Financial Information Disclosure [Abstract]
Revenue	$ 832	$ 212	$ 909	$ 776	$ 622		$ 554	$ 1,077	$ 730	$ 2,729	$ 2,983	$ 896
Cost of revenue	1,260	722	941	801	1,670	[1]	793	1,058	1,383	3,724	4,904	2,430
Gross loss	(428)	(510)	(32)	(25)	(1,048)		(239)	19	(653)	(995)	(1,921)	(1,534)
Total operating expenses	6,442	6,148	6,839	6,747	5,299		5,148	4,388	4,949	26,176	19,784	13,014
Operating loss	(6,870)	(6,658)	(6,871)	(6,772)	(6,347)		(5,387)	(4,369)	(5,602)	(27,171)	(21,705)	(14,548)
Total other income (expense)	(359)	(404)	(432)	(397)	(201)		(3,062)	(1,341)	1,768	(1,592)	(2,836)	(143)
Net loss	$ (7,229)	$ (7,062)	$ (7,303)	$ (7,169)	$ (6,548)		$ (8,449)	$ (5,710)	$ (3,834)	$ (28,763)	$ (24,541)	$ (14,691)
Net loss per share-basic and diluted	$ (0.06)	$ (0.06)	$ (0.07)	$ (0.07)	$ (0.06)		$ (0.10)	$ (0.08)	$ (0.05)	$ (0.25)	$ (0.29)	$ (0.20)
[1]	Includes $536 from the correction of an immaterial error related to inventory overhead costs that were overstated in the 2013 consolidated financial statements.