Vocera Communications (VCRA) 10-Q 5 Aug 19 2019 Q2 Quarterly report Financial data

Document and Entity Information

Document and Entity Information - shares	6 Months Ended
	Jun. 30, 2019	Aug. 01, 2019
Entity Listings [Line Items]
Document Type	10-Q
Document Quarterly Report	true
Document Period End Date	Jun. 30, 2019
Document Transition Report	false
Entity File Number	001-35469
Entity Registrant Name	VOCERA COMMUNICATIONS, INC.
Entity Incorporation, State or Country Code	DE
Entity Tax Identification Number	94-3354663
Entity Address, Address Line One	525 Race Street
Entity Address, City or Town	San Jose
Entity Address, State or Province	CA
Entity Address, Postal Zip Code	95126
City Area Code	408
Local Phone Number	882-5100
Entity Current Reporting Status	Yes
Entity Interactive Data Current	Yes
Entity Filer Category	Large Accelerated Filer
Entity Small Business	false
Entity Emerging Growth Company	false
Entity Shell Company	false
Entity Common Stock, Shares Outstanding		31,460,653
Entity Central Index Key	0001129260
Amendment Flag	false
Document Fiscal Year Focus	2019
Document Fiscal Period Focus	Q2
Current Fiscal Year End Date	--12-31
New York Stock Exchange
Entity Listings [Line Items]
Title of 12(b) Security	Common Stock, $0.0003 par value
Trading Symbol	VCRA
Security Exchange Name	NYSE

Condensed Consolidated Balance

Condensed Consolidated Balance Sheets - USD ($) $ in Thousands	Jun. 30, 2019	Dec. 31, 2018
Current assets
Cash and cash equivalents	$ 44,901	$ 34,276
Short-term investments	170,487	186,894
Accounts receivable, net of allowance	29,702	40,127
Other receivables	5,578	4,148
Inventories	5,184	4,350
Prepaid expenses and other current assets	4,938	4,691
Total current assets	260,790	274,486
Property and equipment, net	7,422	7,468
Operating lease right of use asset	5,409
Intangible assets, net	7,038	9,070
Goodwill	49,246	49,246
Deferred commissions	9,918	10,303
Other long-term assets	7,189	1,525
Total assets	341,603	352,098
Current liabilities
Accounts payable	3,378	4,217
Accrued payroll and other current liabilities	12,902	12,885
Deferred revenue, current	42,303	44,053
Total current liabilities	58,583	61,155
Deferred revenue, long-term	10,302	14,579
Convertible senior notes, net	113,759	110,540
Other long-term liabilities	4,576
Other long-term liabilities	6,479	2,957
Total liabilities	189,123	189,231
Commitments and contingencies (Note 9)
Stockholders' equity
Preferred stock, $0.0003 par value - 5,000,000 shares authorized as of March 31, 2019 and December 31, 2018; zero shares issued and outstanding	0	0
Common stock, $0.0003 par value - 100,000,000 shares authorized as of March 31, 2019 and December 31, 2018; 30,891,117 and 30,708,138 shares issued and outstanding as of March 31, 2019 and December 31, 2018, respectively	9	9
Additional paid-in capital	301,133	295,647
Accumulated other comprehensive loss	276	(443)
Accumulated deficit	(148,938)	(132,346)
Total stockholders’ equity	152,480	162,867
Total liabilities and stockholders’ equity	$ 341,603	$ 352,098

Condensed Consolidated Balanc_2

Condensed Consolidated Balance Sheets Condensed Consolidated Balance Sheets (Paranthetical) - $ / shares	Jun. 30, 2019	Dec. 31, 2018
Liabilities and stockholders' equity
Common stock par value	$ 0.0003	$ 0.0003
Common stock shares authorized	100,000,000	100,000,000
Common stock shares issued	31,424,885	30,708,138
Common stock shares outstanding	31,424,885	30,708,138
Preferred Stock
Liabilities and stockholders' equity
Preferred stock par value	$ 0.0003	$ 0.0003
Preferred stock shares authorized	5,000,000	5,000,000
Preferred stock shares issued	0	0
Preferred stock shares outstanding	0	0

Condensed Consolidated Statemen

Condensed Consolidated Statements of Operations - USD ($) $ in Thousands	3 Months Ended
	Jun. 30, 2019	Jun. 30, 2018
Revenue
Total revenue	$ 44,759	$ 42,686
Cost of revenue
Total cost of revenue	17,743	17,035
Gross profit	27,016	25,651
Operating expenses
Research and development	8,943	7,323
Sales and marketing	15,478	15,266
General and administrative	6,535	6,176
Total operating expenses	30,956	28,765
Loss from operations	(3,940)	(3,114)
Interest income	1,332	530
Interest expense	(2,170)	(997)
Other income (expense), net	(159)	(528)
Loss before income taxes	(4,937)	(4,109)
Benefit from income taxes	80	555
Net loss	(4,857)	(3,554)
Product
Revenue
Total revenue	23,132	21,824
Cost of revenue
Total cost of revenue	6,912	6,683
Service
Revenue
Total revenue	21,627	20,862
Cost of revenue
Total cost of revenue	$ 10,831	$ 10,352

Condensed Consolidated Statem_2

Condensed Consolidated Statements of Comprehensive Income - USD ($) $ in Thousands	3 Months Ended		6 Months Ended
	Jun. 30, 2019	Jun. 30, 2018	Jun. 30, 2019	Jun. 30, 2018
Statement of Comprehensive Income [Abstract]
Net loss	$ (4,857)	$ (3,554)	$ (16,592)	$ (8,324)
Other comprehensive loss, net:
Change in unrealized gain (loss) on investments, net of tax	294	(119)	719	(202)
Comprehensive loss	$ (4,563)	$ (3,673)	$ (15,873)	$ (8,526)

Condensed Consolidated Statem_3

Condensed Consolidated Statements of Cash Flows - USD ($) $ in Thousands	6 Months Ended
	Jun. 30, 2019	Jun. 30, 2018
Cash flows from operating activities
Net loss	$ (16,592)	$ (8,324)
Adjustments to reconcile net loss to net cash used in operating activities:
Depreciation and amortization	3,797	3,776
Change in lease-related performance liabilities	(572)	(568)
Stock-based compensation expense	11,653	9,983
Amortization of debt discount and issuance costs	3,219	733
Other	151	24
Changes in operating assets and liabilities:
Accounts receivable	10,425	1,621
Other receivables	(1,468)	(187)
Inventories	(834)	(1,109)
Prepaid expenses and other assets	(541)	672
Deferred commissions	385	972
Accounts payable	(841)	(184)
Increase (Decrease) in Other Accrued Liabilities	(2,674)	(4,256)
Deferred revenue	(6,027)	(1,742)
Net cash used in operating activities	81	1,411
Cash flows from investing activities
Purchase of property and equipment	(1,778)	(1,929)
Purchase of short-term investments	(43,384)	(148,228)
Maturities of short-term investments	61,228	21,707
Net cash used in investing activities	16,066	(128,450)
Cash flows from financing activities
Cash from lease-related performance obligations	645	89
Payment for purchase of capped calls	(8,907)
Proceeds from exercise of stock options	2,091	1,962
Tax withholdings paid on behalf of employees for net share settlement	(10,067)	(8,034)
Net cash provided by financing activities	(5,522)	125,793
Net decrease in cash and cash equivalents	10,625	(1,246)
Cash and cash equivalents at beginning of period	34,276	28,726
Cash and cash equivalents at end of period	44,901	27,480
Supplemental disclosure of non-cash investing and financing activities:
Property and equipment in accounts payable and accrued liabilities	$ 117	$ 909

Condensed Consolidated Statem_4

Condensed Consolidated Statement of SHareholders Equity Statement - USD ($) $ in Thousands	Total	Common Stock [Member]	Additional Paid-in Capital [Member]	AOCI Attributable to Parent [Member]	Retained Earnings [Member]	Restricted stock units	Restricted stock unitsCommon Stock [Member]	Restricted stock unitsAdditional Paid-in Capital [Member]	Convertible Senior Notes At 1.50%, Option PortionConvertible Debt
Shares, Outstanding		29,412,116
Stockholders' Equity, Including Portion Attributable to Noncontrolling Interest	$ 128,000	$ 9	$ 250,854	$ (191)	$ (122,672)
Share-based Compensation Arrangement by Share-based Payment Award, Options, Exercises in Period		59,527
Stock Issued During Period, Value, Stock Options Exercised	958		958
Restricted Stock, Shares Issued Net of Shares for Tax Withholdings							62,834
Adjustments to Additional Paid in Capital, Other	(987)							$ (987)
Adjustments to Additional Paid in Capital, Share-based Compensation, Requisite Service Period Recognition	4,587		4,587
Net loss	(4,770)				(4,770)
Change in unrealized gain (loss) on investments, net of tax	$ (83)			(83)
Stock Issued During Period, Shares, Employee Stock Purchase Plans	78,563
Net loss	$ (8,324)
Change in unrealized gain (loss) on investments, net of tax	(202)
Shares, Outstanding		29,534,477
Stockholders' Equity, Including Portion Attributable to Noncontrolling Interest	127,705	$ 9	255,412	(274)	(127,442)
Share-based Compensation Arrangement by Share-based Payment Award, Options, Exercises in Period		56,683
Stock Issued During Period, Value, New Issues		$ 0
Stock Issued During Period, Value, Stock Options Exercised	1,004		1,004
Restricted Stock, Shares Issued Net of Shares for Tax Withholdings							422,247
Adjustments to Additional Paid in Capital, Other	(6,932)							(6,932)
Stock Issued During Period, Shares, Employee Stock Purchase Plans		78,563
Stock Issued During Period, Value, Employee Stock Purchase Plan	1,625		1,625
Adjustments to Additional Paid in Capital, Share-based Compensation, Requisite Service Period Recognition	5,396		5,396
Net loss	(3,554)				(3,554)
Change in unrealized gain (loss) on investments, net of tax	(119)			(119)
Shares, Outstanding		30,091,970
Stockholders' Equity, Including Portion Attributable to Noncontrolling Interest	148,432	$ 9	279,812	(393)	(130,996)
Cumulative Effect of New Accounting Principle in Period of Adoption	23,307		23,307		0
Shares, Outstanding		30,708,138
Stockholders' Equity, Including Portion Attributable to Noncontrolling Interest	162,867	$ 9	295,647	(443)	(132,346)
Share-based Compensation Arrangement by Share-based Payment Award, Options, Exercises in Period		122,376
Stock Issued During Period, Value, Stock Options Exercised	1,564		1,564
Restricted Stock, Shares Issued Net of Shares for Tax Withholdings							60,603
Adjustments to Additional Paid in Capital, Other	(1,271)							(1,271)
Adjustments to Additional Paid in Capital, Share-based Compensation, Requisite Service Period Recognition	5,544		5,544
Net loss	(11,735)				(11,735)
Change in unrealized gain (loss) on investments, net of tax	$ 425			425
Share-based Compensation Arrangement by Share-based Payment Award, Equity Instruments Other than Options, Vested in Period						804,810
Stock Issued During Period, Shares, Employee Stock Purchase Plans	61,691
Net loss	$ (16,592)
Change in unrealized gain (loss) on investments, net of tax	719
Shares, Outstanding		30,891,117
Stockholders' Equity, Including Portion Attributable to Noncontrolling Interest	157,394	$ 9	301,484	(18)	(144,081)
Share-based Compensation Arrangement by Share-based Payment Award, Options, Exercises in Period		37,239
Stock Issued During Period, Value, Stock Options Exercised	527		527
Restricted Stock, Shares Issued Net of Shares for Tax Withholdings							434,838
Adjustments to Additional Paid in Capital, Other	(8,796)							$ (8,796)
Stock Issued During Period, Shares, Employee Stock Purchase Plans		61,691
Stock Issued During Period, Value, Employee Stock Purchase Plan	1,809		1,809
Adjustments to Additional Paid in Capital, Share-based Compensation, Requisite Service Period Recognition	6,109		6,109
Net loss	(4,857)				(4,857)
Other Comprehensive Income (Loss), Net of Tax	294
Change in unrealized gain (loss) on investments, net of tax	294
Shares, Outstanding		31,424,885
Stockholders' Equity, Including Portion Attributable to Noncontrolling Interest	$ 152,480	$ 9	$ 301,133	$ 276	$ (148,938)
Carrying amount of equity component, net of capped calls									$ 23,307

The Company and Summary of Sign

The Company and Summary of Significant Accounting Policies	6 Months Ended
	Jun. 30, 2019
Accounting Policies [Abstract]
The Company and Summary of Significant Accounting Policies	The Company and Summary of Significant Accounting Policies Organization and Business Vocera Communications, Inc. and its subsidiaries (collectively the “Company” or “Vocera”) is a provider of secure, integrated, intelligent communication and clinical workflow solutions, focused on empowering mobile workers in healthcare, hospitality, retail, energy and other mission-critical mobile work environments, in the United States and internationally. The significant majority of the Company’s business is generated from sales of its solutions in the healthcare market to help its customers improve quality of care, patient and staff experience and increase operational efficiency. The Vocera communication and collaboration solution, includes: an intelligent enterprise software platform; a lightweight, wearable, voice-controlled communication badge; and smartphone applications. The solution enables users to connect instantly with other staff simply by saying the name, function or group name of the desired recipient. It also delivers HIPAA-compliant secure text messages, alerts and alarms directly to a range of smartphones both inside and outside the hospital, replacing legacy pagers and in-building wireless phones. Basis of Presentation The Company’s unaudited condensed consolidated financial statements have been prepared in accordance with accounting principles generally accepted in the United States of America (“GAAP”), pursuant to the instructions to Form 10-Q and Article 10 of Regulation S-X of the U.S. Securities and Exchange Commission, and include the accounts of Vocera and its wholly owned subsidiaries. All intercompany balances and transactions have been eliminated. Certain information and disclosures normally included in financial statements prepared in accordance with GAAP have been condensed or omitted pursuant to such rules and regulations. Accordingly, these unaudited interim condensed consolidated financial statements should be read in conjunction with the annual audited consolidated financial statements and notes thereto contained in the Company’s Annual Report on Form 10-K for the year ended December 31, 2018 . The year-end condensed balance sheet data was derived from the Company’s audited financial statements but does not include all disclosures required by GAAP. In the opinion of management, the accompanying unaudited condensed consolidated financial statements reflect all adjustments, which include only normal recurring adjustments, necessary to present fairly the Company’s interim consolidated financial information. The results for the quarter presented are not necessarily indicative of the results to be expected for the year ending December 31, 2019 or for any other interim period or any other future year. The accounting policies followed in the preparation of these financial statements are consistent in all material respects with those presented in Note 1 to the consolidated financial statements included in the Company’s Annual Report on Form 10-K for the year ended December 31, 2018. Use of Estimates The preparation of the accompanying unaudited condensed consolidated financial statements in conformity with GAAP requires the Company to make estimates and assumptions that affect the reported amounts of assets and liabilities and disclosure of contingent assets and liabilities at the date of the financial statements and the reported amounts of revenue and expense during the reporting periods. The estimates include, but are not limited to, revenue recognition, warranty reserves, inventory reserves, goodwill and intangible assets, stock-based compensation expense, provisions for income taxes and contingencies. Actual results could differ from these estimates, and such differences could be material to the Company’s financial position and results of operations. Leases The Company determines if an arrangement is a lease at inception. Operating leases are included in other long-term assets, accrued payroll and other current liabilities and other long-term liabilities on the consolidated balance sheets. Sales-type leases are included in other receivables, accrued payroll and other current liabilities and other long-term liabilities on the consolidated balance sheets. The Company has elected an accounting policy to not recognize short-term leases (one year or less) on the consolidated balance sheet. The Company also elected the package of practical expedients which applies to leases that commenced before the adoption date. By electing the package of practical expedients, the Company did not need to reassess whether any existing contracts are or contained a lease or the lease classification for any existing leases. Operating lease right of use assets and operating lease liabilities are recognized based on the present value of the lease payments over the lease term at commencement date. As most of the Company’s leases do not provide an implicit rate, the incremental borrowing rate is used based on the information available at commencement date in determining the present value of future payments. The operating lease right of use asset also includes any lease payments made and excludes lease incentives. Lease terms may include options to extend or terminate the lease when it is reasonably certain that the Company will exercise that option. Lease expense for minimum lease payments is recognized on a straight-line basis over the lease term. The Company accounts for lease components and nonlease components as a single lease component. Recently Adopted Accounting Pronouncements In February 2016, the FASB amended lease accounting requirements to begin recording assets and liabilities arising from leases on the balance sheet. The new guidance requires significant additional disclosures about the amount, timing and uncertainty of cash flows from leases. This new guidance was effective beginning on January 1, 2019 under a modified retrospective approach. The modified retrospective approach includes a number of optional practical expedients that entities may elect to apply. The Company elected the package of practical expedients permitted under the transition guidance within the new standard. The adoption of the standard resulted in recognition of right-of-use assets, which includes the impact of existing deferred rents and tenant improvement allowances of $5.1 million and lease liabilities of $6.7 million , respectively as of January 1, 2019. The standard did not affect our consolidated net earnings or cashflows. In February 2018, the FASB issued new guidance which allows a reclassification from accumulated other comprehensive income to retained earnings for stranded tax effects resulting from the Tax Cuts and Jobs Act and required certain disclosures about stranded tax effects. This standard was effective for the Company beginning January 1, 2019 and may be applied either in the period of adoption or retrospectively. Early adoption is permitted. The adoption of this guidance did not have an impact on the Company’s consolidated financial statements. In August 2018, the SEC adopted the final rule under SEC Release No. 33-10532, Disclosure Update and Simplification, amending certain disclosure requirements that were redundant, duplicative, overlapping, outdated or superseded. In addition, the amendments expanded the disclosure requirements on the analysis of stockholders' equity for interim financial statements. Under the amendments, an analysis of changes in each caption of stockholders' equity presented in the balance sheet must be provided in a note or separate statement. The analysis should present a reconciliation of the beginning balance to the ending balance of each period for which a statement of comprehensive income is required to be filed. This final rule was effective on November 5, 2018. The Company adopted this guidance in the first quarter of fiscal year 2019. Recent Accounting Pronouncements In June 2016, the FASB issued new guidance related to the accounting for credit losses on instruments for both financial services and non-financial services entities. The new guidance introduces an approach based on expected losses to estimate credit losses on certain types of financial instruments. It also modifies the impairment model for available-for-sale debt securities and provides for a simplified accounting model for purchased financial assets with credit deterioration since their origination. The guidance will be effective beginning January 1, 2020. Early adoption is permitted. The Company is currently evaluating the impact of this new guidance on its consolidated financial statements. In January 2017, the FASB issued new guidance to simplify the accounting for goodwill impairment. The guidance simplifies the measurement of goodwill impairment by removing step 2 of the goodwill impairment test, which requires the determination of the fair value of individual assets and liabilities of a reporting unit. The new guidance requires goodwill impairment to be measured as the amount by which a reporting unit’s carrying value exceeds its fair value; however, the loss recognized should not exceed the total amount of goodwill allocated to that reporting unit. The amendments should be applied on a prospective basis. The new standard is effective for fiscal years beginning after December 15, 2019 with early adoption permitted for interim or annual goodwill impairment tests performed after January 1, 2017. The Company is evaluating the impact of this new accounting guidance on its consolidated financial statements.

Revenue, deferred revenue, and

Revenue, deferred revenue, and deferred commissions	6 Months Ended
	Jun. 30, 2019
Revenue from Contract with Customer [Abstract]
Revenue, deferred revenue, and deferred commissions	Revenue, deferred revenue and deferred commissions The Company utilizes a five-step approach to recognizing revenue which depicts the transfer of promised goods or services to customers in an amount that reflects the consideration to which the entity expects to be entitled in exchange for those goods or services. • Identification of the contract, or contracts, with a customer - A contract with a customer exists when (i) the Company enters into an enforceable contract with a customer that defines each party’s rights regarding the goods or services to be transferred and identifies the payment terms related to these goods or services, (ii) the contract has commercial substance and, (iii) the Company determines that collection of substantially all consideration for goods or services that are transferred is probable based on the customer’s intent and ability to pay the promised consideration. The Company applies judgment in determining the customer’s ability and intention to pay, which is based on a variety of factors including the customer’s historical payment experience or, in the case of a new customer, published credit and financial information pertaining to the customer. Customer payments received by the Company are non-refundable. • Identification of the performance obligations in the contract - Performance obligations promised in a contract are identified based on the goods or services that will be transferred to the customer that are capable of being both: a) functionally distinct, whereby the customer can benefit from the goods or service either on their own or together with other resources that are readily available from third parties or from the Company, and b) contractually distinct, whereby the transfer of the goods or services is separately identifiable from other promises in the contract. To the extent a contract includes multiple promised goods or services, the Company applies judgment to determine whether promised goods or services are capable of being distinct and distinct in the context of the contract. If these criteria are not met the promised goods or services are accounted for as a combined performance obligation. • Determination of the transaction price - The transaction price is determined based on the consideration to which the Company will be entitled in exchange for transferring goods or services to the customer. • Allocation of the transaction price to the performance obligations in the contract - If the contract contains a single performance obligation, the entire transaction price is allocated to the single performance obligation. Contracts that contain multiple performance obligations require an allocation of the transaction price to each performance obligation based on a relative standalone selling price, or SSP, basis. The Company determines standalone selling price based on the price at which the performance obligation is sold separately. If the standalone selling price is not observable through past transactions, the Company estimates the standalone selling price taking into account available information such as market conditions and internally approved pricing guidelines related to the performance obligations. • Recognition of revenue when, or as, the Company satisfies a performance obligation - The Company satisfies performance obligations either over time or at a point in time as discussed in further detail below. Revenue is recognized at the time the related performance obligation is satisfied by transferring a promised good or service to a customer. Disaggregation of Revenue A typical sales arrangement involves performance obligations, such as the sales of the Company’s proprietary communication Vocera Badge, perpetual software licenses, professional services, and maintenance and support services which entitle customers to unspecified upgrades, patch releases and telephone-based support. The following table depicts the disaggregation of revenue according to revenue type and is consistent with how the Company evaluates its financial performance: Three months ended June 30, Six months ended June 30, (in thousands) 2019 2018 2019 2018 Product revenue Device $ 14,504 $ 15,049 $ 24,564 $ 27,697 Software 8,628 6,775 12,571 15,214 Total product 23,132 21,824 37,135 42,911 Service revenue Maintenance and support 16,928 15,505 33,321 29,470 Professional services and training 4,699 5,357 9,612 10,547 Total service 21,627 20,862 42,933 40,017 Total revenue $ 44,759 $ 42,686 $ 80,068 $ 82,928 Device revenue - In transactions where the Company delivers hardware, the Company considers itself to be the principal in the transaction and records revenue and costs of goods sold on a gross basis. Hardware revenue is generally recognized upon transfer of control to the customer. Software revenue - Revenue from the Company’s software products is generally recognized upon transfer of control to the customer. Maintenance and support revenue - The Company generates maintenance and support revenue primarily from post contract support (PCS) contracts, and, to a lesser extent, from sales of extended warranties on the Vocera Badge. The majority of software sales are in conjunction with PCS contracts, which generally have one-year terms. The Company recognizes revenue from PCS contracts ratably over the contractual service period. The service period typically commences upon transfer of control of the corresponding software products to the customer. The Company recognizes revenue from extended warranty contracts ratably over their contractual service period, which is typically one year. This period starts one year from the date on which the transfer of control on the underlying hardware occurs because the hardware generally carries a one-year warranty. Professional services and training revenue - Professional services and training revenue is generated when the Company installs and configures its software and devices at new or existing customer sites. The Company recognizes revenue related to professional services as they are performed. Contracts with multiple performance obligations - Some of the Company’s contracts with customers contain multiple performance obligations. For these contracts, the Company accounts for individual performance obligations separately if they are distinct. The transaction price is allocated to the separate performance obligations on a relative stand-alone selling price basis. For deliverables that are routinely sold separately, such as maintenance and support on the core offerings, the Company determines SSP by evaluating renewals over the trailing 12-months. For those that are not sold routinely, the Company determines SSP based on its overall pricing trends and objectives, taking into consideration market conditions and other factors, including the value of the contracts and the products sold. Contract balances - The timing of revenue recognition may differ from the timing of invoicing to customers. Accounts receivable are recorded at the invoiced amount. A receivable is recognized in the period the Company delivers goods or provides services or when the right to consideration is unconditional. Payment terms on invoiced amounts are typically 30 days. The balance of accounts receivable, net of allowance for doubtful accounts, as of June 30, 2019 and December 31, 2018 is presented in the accompanying consolidated balance sheets. As of June 30, 2019 and December 31, 2018 contract assets totaling $3.4 million and $2.4 million , respectively, were included in prepaid and other current assets in the condensed consolidated balance sheets. Costs to obtain and fulfill a contract - The Company capitalizes certain incremental contract acquisition costs consisting primarily of commissions paid and the related payroll taxes when customer contracts are signed. The Company determines whether costs should be deferred based on its sales compensation plans, if the commissions are incremental and would not have been incurred absent the execution of the customer contract. Sales commissions for renewals of customer contracts are not commensurate with the commissions paid for the acquisition of the initial contract given the substantive difference in commission rates in proportion to their respective contract values. Commissions paid upon the initial acquisition of a contract are amortized over the estimated period of benefit, which may exceed the term of the initial contract. Accordingly, amortization of deferred costs is recognized on a systematic basis that is consistent with the pattern of revenue recognition allocated to each performance obligation and is included in sales and marketing expense in the condensed consolidated statements of operations. The Company determines its estimated period of benefit by evaluating the expected renewals of its customer contracts, the duration of its relationships with its customers and other factors. Deferred costs are periodically reviewed for impairment. Changes in the balance of total deferred commissions (contract asset) during the three and six months ended June 30, 2019 are as follows: (in thousands) March 31, 2019 Additions Commissions Recognized June 30, 2019 Deferred commissions $ 10,322 $ 1,674 $ (2,078 ) $ 9,918 (in thousands) December 31, 2018 Additions Commissions Recognized June 30, 2019 Deferred commissions $ 10,303 $ 3,401 $ (3,786 ) $ 9,918 Of the $9.9 million total deferred commissions balance as of June 30, 2019 , the Company expects to recognize approximately 47% as commission expense over the next 12 months and the remainder thereafter. Deferred revenue - The Company records deferred revenue when cash payments are received in advance of the performance under the contract. The current portion of deferred revenue represents the amounts that are expected to be recognized as revenue within one year of the consolidated balance sheet date. Changes in the balance of total deferred revenue (contract liability) during the three and six months ended June 30, 2019 are as follows: (in thousands) March 31, 2019 Additions Revenue Recognized June 30, 2019 Deferred revenue $ 52,945 $ 18,264 $ (18,604 ) $ 52,605 (in thousands) December 31, 2018 Additions Revenue Recognized June 30, 2019 Deferred revenue $ 58,632 $ 33,182 $ (39,209 ) $ 52,605 Revenue recognized during the three and six months ended June 30, 2019 from deferred revenue balances at the beginning of the period was $17.0 million and $29.4 million , respectively. Revenue recognized during the three and six months ended June 30, 2018 from deferred revenue balances at the beginning of the period was $15.5 million and $27.1 million , respectively. The majority of the Company’s “contracted but not recognized” performance obligations are not subject to cancellation terms. The Company’s “contracted but not recognized” revenue, which represents revenue allocated to performance obligations for revenue contracted, and which includes deferred revenue and non-cancelable amounts that will be invoiced and recognized as revenue in future periods, was $116.4 million as of June 30, 2019 , of which the Company expects to recognize approximately 62% as revenue over the next 12 months and the remainder thereafter.

Fair Value of Financial Instrum

Fair Value of Financial Instruments	6 Months Ended
	Jun. 30, 2019
Fair Value Disclosures [Abstract]
Fair Value of Financial Instruments	Fair Value of Financial Instruments The Company’s cash, cash equivalents and short-term investments are carried at their fair values with any differences from their amortized cost recorded in equity as unrealized gains (losses) on marketable securities. As a basis for determining the fair value of its assets and liabilities, the Company follows a three-tier fair value hierarchy, which prioritizes the inputs used in measuring fair value as follows: (Level 1) observable inputs such as quoted prices in active markets; (Level 2) inputs other than the quoted prices in active markets that are observable either directly or indirectly; and (Level 3) unobservable inputs in which there is little or no market data which requires the Company to develop its own assumptions. This hierarchy requires the Company to use observable market data, when available, and to minimize the use of unobservable inputs when determining fair value. During the six months ended June 30, 2019 , there have been no transfers between Level 1 and Level 2 fair value instruments and no transfers in or out of Level 3. The Company’s money market funds are classified within Level 1 of the fair value hierarchy because they are valued using quoted market prices. The fair value of the Company’s Level 2 fixed income securities is obtained from independent pricing services, which may use quoted market prices for identical or comparable instruments or model-driven valuations using observable market data or other inputs, corroborated by observable market data. The Company does not have any financial instruments which are valued using Level 3 inputs. In addition to its cash, cash equivalents and short-term investments, the Company measures the fair value of its Convertible Senior Notes on a quarterly basis for disclosure purposes. The Company considers the fair value of the Convertible Senior Notes at June 30, 2019 to be a Level 2 measurement due to limited trading activity of the Convertible Senior Notes. Refer to Note 8 to the consolidated financial statements for further information. The Company’s assets that are measured at fair value on a recurring basis, by level, within the fair value hierarchy as of June 30, 2019 and December 31, 2018 , are summarized as follows (in thousands): June 30, 2019 December 31, 2018 Level 1 Level 2 Total Level 1 Level 2 Total Assets Money market funds $ 3,630 $ — $ 3,630 $ 3,737 $ — $ 3,737 Commercial paper — 39,945 39,945 — 16,570 16,570 U.S. government agency securities — 1,269 1,269 — 3,325 3,325 U.S. Treasury securities — 240 240 — 2,730 2,730 Corporate debt securities — 161,020 161,020 — 166,759 166,759 Total assets measured at fair value $ 3,630 $ 202,474 $ 206,104 $ 3,737 $ 189,384 $ 193,121

Cash, Cash Equivalents and Shor

Cash, Cash Equivalents and Short-term Investments	6 Months Ended
	Jun. 30, 2019
Cash and Cash Equivalents [Abstract]
Cash, Cash Equivalents, and Short-term Investments	Cash, Cash Equivalents and Short-Term Investments The following tables present cash, cash equivalents and short-term investments (in thousands) as of June 30, 2019 and December 31, 2018 : As of June 30, 2019 Amortized Cost Unrealized Gains Unrealized Losses Fair value Cash and cash equivalents: Demand deposits and other cash $ 9,284 $ — $ — $ 9,284 Money market funds 3,630 — — 3,630 Commercial paper 31,994 — (7 ) 31,987 Total cash and cash equivalents 44,908 — (7 ) 44,901 Short-Term Investments: Commercial paper 7,950 8 — 7,958 U.S. government agency securities 1,270 — (1 ) 1,269 U.S. Treasury securities 240 — — 240 Corporate debt securities 160,447 585 (12 ) 161,020 Total short-term investments 169,907 593 (13 ) 170,487 Total cash, cash equivalents and short-term investments $ 214,815 $ 593 $ (20 ) $ 215,388 As of December 31, 2018 Amortized Cost Unrealized Gains Unrealized Losses Fair value Cash and cash equivalents: Demand deposits and other cash $ 28,049 $ — $ — $ 28,049 Money market funds 3,737 — — 3,737 Commercial paper 2,491 — (1 ) 2,490 Total cash and cash equivalents 34,277 — (1 ) 34,276 Short-Term Investments: Commercial paper 14,091 — (11 ) 14,080 U.S. government agency securities 3,339 — (14 ) 3,325 U.S. Treasury securities 2,740 — (10 ) 2,730 Corporate debt securities 167,110 28 (379 ) 166,759 Total short-term investments 187,280 28 (414 ) 186,894 Total cash, cash equivalents and short-term investments $ 221,557 $ 28 $ (415 ) $ 221,170 The Company has determined that the unrealized losses on its short-term investments as of June 30, 2019 and December 31, 2018 do not constitute an “other than temporary impairment.” The unrealized losses for the short-term investments have all been in a continuous unrealized loss position for less than twelve months. The Company’s conclusion of no “other than temporary impairment” is based on the high credit quality of the securities, their short remaining maturity and the Company’s intent and ability to hold such loss securities until maturity. Classification of the cash, cash equivalents and short-term investments by contractual maturity was as follows: (in thousands) One year or shorter Between 1 and 2 years Total Balances as of June 30, 2019 Cash and cash equivalents (1) $ 44,901 $ — $ 44,901 Short-term investments 108,573 61,914 170,487 Cash, cash equivalents and short-term investments $ 153,474 $ 61,914 $ 215,388 Balances as of December 31, 2018 Cash and cash equivalents (1) $ 34,276 $ — $ 34,276 Short-term investments 109,451 77,443 186,894 Cash, cash equivalents and short-term investments $ 143,727 $ 77,443 $ 221,170 (1) Includes demand deposits and other cash, money market funds and other cash equivalent securities, all with 0-90 day maturity at purchase.

Net Loss Per Share

Net Loss Per Share	6 Months Ended
	Jun. 30, 2019
Earnings Per Share [Abstract]
Net Loss Per Share	Net Loss Per Share The following table sets forth the computation of basic and diluted net loss per share (in thousands, except per share amounts): Three months ended June 30, Six months ended June 30, 2019 2018 2019 2018 Numerator: Net loss $ (4,857 ) $ (3,554 ) $ (16,592 ) $ (8,324 ) Denominator: Weighted average shares used to compute net loss per common share - basic and diluted 31,242 29,867 31,022 29,673 Net loss per share Basic $ (0.16 ) $ (0.12 ) $ (0.53 ) $ (0.28 ) Diluted $ (0.16 ) $ (0.12 ) $ (0.53 ) $ (0.28 ) The following securities were not included in the calculation of diluted shares outstanding as the effect would have been anti-dilutive: Three months ended June 30, Six months ended June 30, (in thousands) 2019 2018 2019 2018 Options to purchase common stock, including ESPP 656 1,236 690 1,283 Restricted stock units 1,671 1,955 1,760 1,991

Goodwill and Intangible Assets

Goodwill and Intangible Assets	6 Months Ended
	Jun. 30, 2019
Goodwill and Intangible Assets Disclosure [Abstract]
Goodwill and Intangible Assets	Goodwill and Intangible Assets Goodwill As of June 30, 2019 and December 31, 2018 , the Company had $49.2 million and $49.2 million of goodwill, respectively, with $41.2 million and $8.0 million allocated to the Company’s Product and Services operating segments, respectively. As of June 30, 2019 , there were no changes in circumstances indicating that the carrying values of goodwill or acquired intangibles may not be recoverable. Intangible Assets Acquisition-related intangible assets are amortized either straight-line, or over the life of the assets on a basis that resembles the economic benefit of the assets. This yields amortization in the latter case that is higher in earlier periods of the useful life. The estimated useful lives and carrying value of acquired intangible assets are as follows: June 30, 2019 December 31, 2018 (in thousands) Range of Useful Life (years) Gross Carrying Amount Accumulated Amortization Net Carrying Amount Gross Carrying Amount Accumulated Amortization Net Carrying Amount Developed technology 3 to 7 $ 10,050 $ 8,945 $ 1,105 $ 10,050 $ 7,731 $ 2,319 Customer relationships 7 to 9 10,920 5,249 5,671 10,920 4,645 6,275 Backlog 3 1,400 1,249 151 1,400 1,203 197 Non-compete agreements 2 to 4 460 460 — 460 460 — Trademarks 3 to 7 1,110 999 111 1,110 831 279 Intangible assets, net book value $ 23,940 $ 16,902 $ 7,038 $ 23,940 $ 14,870 $ 9,070 Amortization expense was $1.0 million and $1.0 million for the three months ended June 30, 2019 and 2018 , respectively. Amortization expense was $2.0 million and $2.3 million for the six months ended June 30, 2019 and 2018 , respectively. Amortization of acquired intangible assets is reflected in the cost of revenue for developed technology and backlog and in operating expenses for the other intangible assets. The estimated future amortization of existing acquired intangible assets as of June 30, 2019 was as follows: (in thousands) Future amortization 2019 (remaining six months) $ 1,691 2020 1,242 2021 1,130 2022 1,050 2023 1,050 2024 875 Future amortization expense $ 7,038

Balance Sheet Components

Balance Sheet Components	6 Months Ended
	Jun. 30, 2019
Balance Sheet Components [Abstract]
Balance Sheet Components	Balance Sheet Components Inventories (in thousands) June 30, December 31, Raw materials $ 197 $ 197 Finished goods 4,987 4,153 Total inventories $ 5,184 $ 4,350 Property and equipment, net (in thousands) June 30, December 31, Computer equipment and software $ 11,692 $ 10,433 Furniture, fixtures and equipment 2,279 2,246 Leasehold improvements 5,140 5,183 Manufacturing tools and equipment 2,534 2,371 Construction in process 410 520 Property and equipment, at cost 22,055 20,753 Less: Accumulated depreciation (14,633 ) (13,285 ) Property and equipment, net $ 7,422 $ 7,468 Depreciation and amortization expense was $0.9 million and $0.8 million for the three months ended June 30, 2019 and 2018 , respectively. Depreciation and amortization expense was $1.8 million and $1.5 million for the six months ended June 30, 2019 and 2018 , respectively. Net investment in sales-type leases The Company has sales-type leases with terms of 3 to 4 years. Sales-type lease receivables are collateralized by the underlying equipment. The components of the Company’s net investment in sales-type leases are as follows: (in thousands) June 30, December 31, Minimum payments to be received on sales-type leases $ 2,612 $ 2,111 Less: Unearned interest income and executory revenue portion (1,326 ) (1,387 ) Net investment in sales-type leases 1,286 724 Less: Current portion (742 ) (427 ) Non-current net investment in sales-type leases $ 544 $ 297 Sales-type lease activity recognized in the consolidated statement of operations are as follows: Three months ended June 30, Six months ended June 30, (in thousands) 2019 2018 2019 2018 Lease revenue $ 2,703 $ 491 $ 3,364 $ 1,500 Less: Cost of lease shipments (805 ) (91 ) (857 ) (228 ) Gross profit 1,898 400 2,507 1,272 Interest income (expense), net on lease receivable 3 — — (1 ) Initial direct cost incurred 109 26 140 72 There were no allowances for doubtful accounts on these leases as of June 30, 2019 and December 31, 2018 . There is no guaranteed or unguaranteed residual value on the leased equipment. The current and non-current net investments in sales-type leases are reported as components of the consolidated balance sheet captions “other receivables” and “other long-term assets,” respectively. The minimum payments expected to be received for future years under sales-type leases as of June 30, 2019 were as follows: (in thousands) Future lease payments 2019 (remaining six months) $ 629 2020 1,049 2021 518 2022 338 2023 78 Total $ 2,612 Accrued payroll and other current liabilities (in thousands) June 30, December 31, Payroll and related expenses $ 5,946 $ 7,241 Accrued payables 2,214 2,115 Operating lease liabilities, current portion 1,997 — Lease financing, current portion 961 956 Product warranty 355 376 Customer prepayments 376 629 Sales and use tax payable 336 379 Other 717 1,189 Total accrued payroll and other current liabilities $ 12,902 $ 12,885 The changes in the Company’s product warranty reserve are as follows: Three months ended June 30, Six months ended June 30, (in thousands) 2019 2018 2019 2018 Warranty balance at the beginning of the period $ 374 $ 303 $ 376 $ 353 Warranty expense accrued for shipments during the period 92 129 169 215 Changes in estimate related to pre-existing warranties (55 ) (75 ) (86 ) (134 ) Warranty settlements made (56 ) (51 ) (104 ) (128 ) Total product warranty $ 355 $ 306 $ 355 $ 306 Leases The Company has operating leases for office space at its headquarters and subsidiaries under non-cancelable operating leases. Leases with an initial term of 12 months or less are not recorded on the balance sheet; lease expense for these leases is recognized on a straight-line basis over the lease term. The Company’s lease terms have remaining lease terms of six months to four years. Operating lease cost, including short-term operating leases was $0.5 million and $0.7 million for the three months ended June 30, 2019 and 2018, respectively and $1.1 million and $1.3 million for the six months ended June 30, 2019 and 2018, respectively. Supplemental balance sheet information related to leases was as follows: (in thousands) June 30, Other long-term assets $ 5,409 Accrued payroll and other current liabilities 1,997 Other long-term liabilities 4,576 Total operating lease liabilities $ 6,573 Other information related to leases was as follows: Three months ended June 30, Six months ended June 30, (in thousands) 2019 2019 Supplemental Cash Flow Information Cash paid for amounts included in the measurement of lease liabilities $ 634 $ 1,264 Right-of-use assets obtained in exchange for lease obligations $ 329 $ 1,018 Weighted average remaining lease term 2.84 years 2.84 years Weighted average discount rate 8 % 8 % Maturities of lease liabilities as of June 30, 2019 are as follows: (in thousands) Operating leases 2019 (remaining six months) $ 1,126 2020 2,631 2021 2,585 2022 977 2023 35 Total maturities of lease liabilities 7,354 Less imputed interest $ (781 ) Total $ 6,573

Convertible Senior Notes

Convertible Senior Notes	6 Months Ended
	Jun. 30, 2019
Debt Disclosure [Abstract]
Convertible Senior Notes	Convertible Senior Notes In May 2018, the Company issued $143.75 million aggregate principal amount of 1.50% Convertible Senior Notes due 2023, including $18.75 million aggregate principal amount of such notes pursuant to the exercise in full of options granted to the initial purchasers, collectively the “Notes.” The Notes are unsecured, unsubordinated obligations and bear interest at a fixed rate of 1.50% per annum, payable semi-annually in arrears on May 15 and November 15 of each year, commencing on November 15, 2018. The total net proceeds from the offering, after deducting initial purchase discounts and estimated debt issuance costs, were approximately $138.9 million . Each $1,000 principal amount of the Notes will initially be convertible into 31.0073 shares of the Company’s common stock, the “Conversion Option,” which is equivalent to an initial conversion price of approximately $32.25 per share, subject to adjustment upon the occurrence of specified events. The Notes will be convertible at the option of the holders at any time prior to the close of business on the business day immediately preceding February 15, 2023, only under the following circumstances: (1) during any calendar quarter commencing after the calendar quarter ending on June 30, 2018 (and only during such calendar quarter), if the last reported sale price of the Company common stock for at least 20 trading days (whether or not consecutive) during a period of 30 consecutive trading days ending on the last trading day of the immediately preceding calendar quarter is greater than or equal to 130% of the conversion price of the Notes on each applicable trading day; (2) during the five business day period after any ten consecutive trading day period in which the trading price per $1,000 principal amount of the Notes for each day of that ten day consecutive trading day period was less than 98% of the product of the last reported sale price of the Company’s common stock and the conversion rate of the Notes on such trading day; or (3) upon the occurrence of specified corporate events (as set forth in the indenture governing the Notes). On or after February 15, 2023 until the close of business on the second scheduled trading day immediately preceding the maturity date, holders may convert their Notes at any time, regardless of the foregoing circumstances. Upon conversion, the Company will pay or deliver, as the case may be, cash, shares of the Company’s common stock or a combination of cash and shares of the Company’s common stock, at the Company’s election. If certain specified fundamental changes occur (as set forth in the indenture governing the Notes) prior to the maturity date, holders of the Notes may require the Company to repurchase for cash all or any portion of their Notes at a repurchase price equal to 100% of the principal amount of the Notes to be repurchased, plus accrued and unpaid interest to, but excluding, the fundamental change repurchase date. In addition, if specific corporate events occur prior to the applicable maturity date, the Company will increase the conversion rate for a holder who elects to convert their notes in connection with such a corporate event in certain circumstances. It is the Company’s current intent and policy to settle conversions through combination settlement which involves repayment of the principal portion in cash and any excess of the conversion value over the principal amount in shares of its common stock. During the six months ended June 30, 2019 , the conditions allowing holders of the Notes to convert have not been met. The Notes are therefore not convertible during the six months ended June 30, 2019 and are classified as long-term debt. In accounting for the transaction, the Notes were separated into liability and equity components. The carrying amount of the liability component was calculated by measuring the fair value of a similar debt instrument that does not have an associated convertible feature. The carrying amount of the equity component representing the Conversion Option was $33.4 million and was determined by deducting the fair value of the liability component from the par value of the Notes. The equity component was recorded in additional paid-in capital and will be remeasured as long as it continues to meet the conditions for equity classification. The excess of the principal amount of the liability component over its carrying amount, the “debt discount,” is amortized to interest expense over the contractual term of the Notes at an effective interest rate of 7.6% . In accounting for the debt issuance costs of $4.9 million related to the Notes, the Company allocated the total amount incurred to the liability and equity components of the Notes based on their relative values. Issuance costs attributable to the liability component were $3.8 million and will be amortized to interest expense using the effective interest method over the contractual term of the Notes. Issuance costs attributable to the equity component were $1.1 million and are included with the equity component in additional paid-in capital. The Notes consist of the following: (in thousands) June 30, December 31, Liability: Principal $ 143,750 $ 143,750 Unamortized debt discount (26,953 ) (29,846 ) Unamortized issuance costs (3,038 ) (3,364 ) Net carrying amount $ 113,759 $ 110,540 Stockholders’ equity: Debt discount for conversion option $ 33,350 $ 33,350 Issuance costs $ (1,136 ) $ (1,136 ) Net carrying amount $ 32,214 $ 32,214 The total estimated fair value of the Notes as of June 30, 2019 was approximately $176.9 million . The fair value was determined based on the closing trading price per $100 of the Notes as of the last day of trading for the period. The fair value of the Notes is primarily affected by the trading price of the Company’s common stock and market interest rates. Based on the closing price of the Company’s common stock of $31.92 on June 28, 2019, the if-converted value of the Notes of $142.3 million was less than their principal amount. Interest expense related to the Notes is as follows: Three months ended June 30, Six months ended June 30, (in thousands) 2019 2018 2019 2018 Contractual interest expense $ 539 $ 264 $ 1,078 $ 264 Amortization of debt discount 1,471 659 2,893 659 Amortization of issuance costs 166 74 326 74 Total interest expense $ 2,176 $ 997 $ 4,297 $ 997 Capped Calls In connection with the pricing of the Notes, the Company entered into privately negotiated capped call transactions with certain counterparties, the “Capped Calls.” The Capped Calls each have an initial strike price of approximately $32.25 per share, subject to certain adjustments, which correspond to the initial conversion price of the Notes. The Capped Calls have initial cap prices of $38.94 per share, subject to certain adjustments. The Capped Calls cover, subject to anti-dilution adjustments, approximately 4.5 million shares of the Company’s common stock. Conditions that cause adjustments to the initial strike price of the Capped Calls mirror conditions that result in corresponding adjustments for the Notes. The Capped Calls are generally intended to reduce or offset the potential dilution to the Company’s common stock upon any conversion of the Notes with such reduction or offset, as the case may be, subject to a cap based on the cap price. For accounting purposes, the Capped Calls are separate transactions, and not part of the terms of the Notes. As these transactions meet certain accounting criteria, the Capped Calls are recorded in stockholders' equity and are not accounted for as derivatives. The cost of $8.9 million incurred in connection with the Capped Calls was recorded as a reduction to additional paid-in capital. The net impact to the Company’s stockholders' equity, included in additional paid-in capital, of the above components of the Notes is as follows: (in thousands) June 30, Conversion option $ 33,350 Purchase of capped calls $ (8,907 ) Issuance costs $ (1,136 ) Total $ 23,307 Impact on Earnings Per Share The Notes will not have an impact on the Company’s diluted earnings per share until they meet the criteria for conversion, as discussed above, as the Company intends to settle the principal amount of the Notes in cash upon conversion. Under the treasury stock method, in periods when the Company reports net income, the Company is required to include the effect of additional shares that may be issued under the Notes when the price of its’ common stock exceeds the conversion price. However, upon conversion, there will be no economic dilution from the Notes until the average market price of the Company’s common stock exceeds the cap price of $38.94 per share, as exercise of the capped calls offsets any dilution from the Notes from the conversion price up to the cap price. Capped Calls are excluded from the calculation of diluted earnings per share, as they would be anti-dilutive under the treasury stock method.

Commitments

Commitments	6 Months Ended
	Jun. 30, 2019
Commitments and Contingencies Disclosure [Abstract]
Commitments and Contingencies Disclosure	Commitments and Contingencies Non-cancelable Material Commitments The Company is required to purchase unused, non-cancelable, non-returnable raw material inventory that was purchased by its contract manufacturers based on committed finished goods orders from the Company, certain long lead-time raw materials based on the Company’s forecast and current work-in-progress materials. As of June 30, 2019 and December 31, 2018 , approximately $11.5 million and $11.1 million , respectively, of such inventory was purchased and held by the third-party manufacturers which was subject to these purchase guarantees. Indemnifications The Company undertakes, in the ordinary course of business, to (i) defend customers and other parties from certain third-party claims associated with allegations of trade secret misappropriation, infringement of copyright, patent or other intellectual property rights, tortious damage to persons or property or breaches of certain Company obligations relating to confidentiality (e.g., safeguarding protected health information) and (ii) indemnify and hold harmless such parties from certain resulting damages, costs and other liabilities. The term of these undertakings may be perpetual and the maximum potential liability of the Company under certain of these undertakings is not determinable. Based on its historical experience, the Company believes the liability associated with these undertakings is minimal. The Company has entered into indemnification agreements with its directors and officers that may require the Company to indemnify its directors and officers against liabilities that may arise by reason of their status or service as directors or officers, other than liabilities arising from willful misconduct of the individual. The Company currently has directors and officers insurance. As there has been no significant history of losses, no expense accrual has been made. Litigation From time to time, the Company may be involved in lawsuits, claims, investigations and proceedings, consisting of intellectual property, commercial, employment and other matters which arise in the ordinary course of business. The Company defends itself vigorously against any such claims. Although the outcome of these matters is currently not determinable, management expects that any losses from existing matters that are probable or reasonably possible of being incurred as a result of these matters would not be material to the financial statements as a whole.

Stock-based Compensation and Aw

Stock-based Compensation and Awards	6 Months Ended
	Jun. 30, 2019
Disclosure of Compensation Related Costs, Share-based Payments [Abstract]
Stock-based Compensation and Award	Stock-based Compensation and Awards Stock Option Activity A summary of the stock option activity for the six months ended June 30, 2019 is presented below: Options Outstanding Number of options Weighted average exercise price Weighted average remaining contractual term Aggregate intrinsic value (in years) (in thousands) Outstanding at December 31, 2018 797,501 $ 13.31 4.71 $ 20,767 Options granted — — Options exercised (159,615 ) 13.10 Options canceled — — Outstanding at June 30, 2019 637,886 $ 13.36 4.11 $ 11,838 At June 30, 2019 , there was no unrecognized compensation cost related to options. As of June 30, 2019 , there were 2,017,431 shares that remained available for future issuance of options, restricted stock units (“RSUs”) or other equity awards under the 2012 Equity Incentive Plan. Employee Stock Purchase Plan In March 2012, the Company’s 2012 Employee Stock Purchase Plan (the “ESPP”) was approved. During the six months ended June 30, 2019 employees purchased 61,691 shares of common stock at an average price of $29.32 . During the six months ended June 30, 2018, employees purchased 78,563 shares of common stock at an average price of $20.69 . As of June 30, 2019 , there were 966,693 shares available for future issuance under the ESPP. The following Black-Scholes option-pricing assumptions were used for each respective period for the ESPP: Three months ended June 30, Six months ended June 30, 2019 2018 2019 2018 Expected term (in years) 0.50 0.50 0.50 0.50 Volatility 33% - 45.2% 29% - 37.8% 33% - 45.2% 29% - 37.8% Risk-free interest rate 2.43% - 2.51% 1.39% - 2.09% 2.43% - 2.51% 1.39% - 2.09% Dividend yield 0% 0% 0% 0% Restricted Stock Units A summary of RSU activity for the six months ended June 30, 2019 is presented below: Restricted Stock Units Number of shares Weighted Average Grant Date Fair Value per Share Outstanding at December 31, 2018 1,807,180 $ 23.13 Granted 728,625 33.25 Vested (804,810 ) 21.17 Forfeited (60,442 ) 25.86 Outstanding at June 30, 2019 1,670,553 $ 28.39 At June 30, 2019 , there was $39.8 million of unrecognized compensation cost related to RSUs, which is expected to be recognized over a weighted-average period of 1.92 years . Allocation of Stock-Based Compensation Expense The following table presents the allocation of stock-based compensation expense: Three months ended June 30, Six months ended June 30, (in thousands) 2019 2018 2019 2018 Cost of revenue $ 1,178 $ 966 $ 2,156 $ 1,713 Research and development 1,034 755 1,856 1,362 Sales and marketing 1,758 1,655 3,478 3,151 General and administrative 2,139 2,020 4,163 3,757 Total stock-based compensation $ 6,109 $ 5,396 $ 11,653 $ 9,983

Segments

Segments	6 Months Ended
	Jun. 30, 2019
Segment Reporting [Abstract]
Segments	Segments The Company has two operating segments, which are both reportable business segments: (i) Product and (ii) Service, both of which are comprised of Vocera and its wholly-owned subsidiaries’ results of operations. The following table presents a summary of the operating segments: Three months ended June 30, Six months ended June 30, 2019 2018 2019 2018 (in thousands) Revenue Product $ 23,132 $ 21,824 $ 37,135 $ 42,911 Service 21,627 20,862 42,933 40,017 Total revenue 44,759 42,686 80,068 82,928 Cost of revenue Product 6,912 6,683 12,246 13,028 Service 10,831 10,352 21,121 20,348 Total cost of revenue 17,743 17,035 33,367 33,376 Gross profit Product 16,220 15,141 24,889 29,883 Service 10,796 10,510 21,812 19,669 Total gross profit 27,016 25,651 46,701 49,552 Operating expenses 30,956 28,765 61,701 57,460 Interest income (expense), net and other (997 ) (995 ) (1,708 ) (1,059 ) Loss before income taxes $ (4,937 ) $ (4,109 ) $ (16,708 ) $ (8,967 )

Income Taxes

Income Taxes	6 Months Ended
	Jun. 30, 2019
Income Tax Disclosure [Abstract]
Income Taxes	Income Taxes The Company recorded a $0.1 million and $0.6 million benefit from income taxes for the six months ended June 30, 2019 and 2018 , respectively. The benefit recorded for the six months ended June 30, 2019 was primarily due to the accretion of the deferred tax liability associated with indefinite lived intangibles, the tax effect of unrealized gains on investments recorded within other comprehensive income, taxes on international operations and state income taxes. The benefit recorded for the six months ended June 30, 2018 was primarily due to a reduction in the U.S. valuation allowance attributable to indefinite lived intangibles becoming a source of future taxable income to realize the deferred tax asset recorded for the U.S. federal net operating loss generated in the current year. This deferred tax asset will have an indefinite carryforward period as a result of recently enacted tax law changes. The benefit recorded was offset by taxes on international operations and state income taxes. As of June 30, 2019 , the Company has provided a valuation allowance against certain federal and state deferred tax assets. Management continues to evaluate the realizability of deferred tax assets and the related valuation allowance. If management’s assessment of the deferred tax assets or the corresponding valuation allowance were to change, the Company would record the related adjustment to income during the period in which management makes the determination. As of June 30, 2019 , there were no material changes to either the nature or the amounts of the uncertain tax positions previously determined for the year ended December 31, 2018

The Company and Summary of Si_2

The Company and Summary of Significant Accounting Policies (Policies)	6 Months Ended
	Jun. 30, 2019
Accounting Policies [Abstract]
Nature of Operations	Organization and Business Vocera Communications, Inc. and its subsidiaries (collectively the “Company” or “Vocera”) is a provider of secure, integrated, intelligent communication and clinical workflow solutions, focused on empowering mobile workers in healthcare, hospitality, retail, energy and other mission-critical mobile work environments, in the United States and internationally. The significant majority of the Company’s business is generated from sales of its solutions in the healthcare market to help its customers improve quality of care, patient and staff experience and increase operational efficiency. The Vocera communication and collaboration solution, includes: an intelligent enterprise software platform; a lightweight, wearable, voice-controlled communication badge; and smartphone applications. The solution enables users to connect instantly with other staff simply by saying the name, function or group name of the desired recipient. It also delivers HIPAA-compliant secure text messages, alerts and alarms directly to a range of smartphones both inside and outside the hospital, replacing legacy pagers and in-building wireless phones.
Basis of Presentation	Basis of Presentation The Company’s unaudited condensed consolidated financial statements have been prepared in accordance with accounting principles generally accepted in the United States of America (“GAAP”), pursuant to the instructions to Form 10-Q and Article 10 of Regulation S-X of the U.S. Securities and Exchange Commission, and include the accounts of Vocera and its wholly owned subsidiaries. All intercompany balances and transactions have been eliminated. Certain information and disclosures normally included in financial statements prepared in accordance with GAAP have been condensed or omitted pursuant to such rules and regulations. Accordingly, these unaudited interim condensed consolidated financial statements should be read in conjunction with the annual audited consolidated financial statements and notes thereto contained in the Company’s Annual Report on Form 10-K for the year ended December 31, 2018 . The year-end condensed balance sheet data was derived from the Company’s audited financial statements but does not include all disclosures required by GAAP. In the opinion of management, the accompanying unaudited condensed consolidated financial statements reflect all adjustments, which include only normal recurring adjustments, necessary to present fairly the Company’s interim consolidated financial information. The results for the quarter presented are not necessarily indicative of the results to be expected for the year ending December 31, 2019 or for any other interim period or any other future year.
Use of Estimates	Use of Estimates The preparation of the accompanying unaudited condensed consolidated financial statements in conformity with GAAP requires the Company to make estimates and assumptions that affect the reported amounts of assets and liabilities and disclosure of contingent assets and liabilities at the date of the financial statements and the reported amounts of revenue and expense during the reporting periods. The estimates include, but are not limited to, revenue recognition, warranty reserves, inventory reserves, goodwill and intangible assets, stock-based compensation expense, provisions for income taxes and contingencies. Actual results could differ from these estimates, and such differences could be material to the Company’s financial position and results of operations.
Recent Accounting Pronouncements	Recently Adopted Accounting Pronouncements In February 2016, the FASB amended lease accounting requirements to begin recording assets and liabilities arising from leases on the balance sheet. The new guidance requires significant additional disclosures about the amount, timing and uncertainty of cash flows from leases. This new guidance was effective beginning on January 1, 2019 under a modified retrospective approach. The modified retrospective approach includes a number of optional practical expedients that entities may elect to apply. The Company elected the package of practical expedients permitted under the transition guidance within the new standard. The adoption of the standard resulted in recognition of right-of-use assets, which includes the impact of existing deferred rents and tenant improvement allowances of $5.1 million and lease liabilities of $6.7 million , respectively as of January 1, 2019. The standard did not affect our consolidated net earnings or cashflows. In February 2018, the FASB issued new guidance which allows a reclassification from accumulated other comprehensive income to retained earnings for stranded tax effects resulting from the Tax Cuts and Jobs Act and required certain disclosures about stranded tax effects. This standard was effective for the Company beginning January 1, 2019 and may be applied either in the period of adoption or retrospectively. Early adoption is permitted. The adoption of this guidance did not have an impact on the Company’s consolidated financial statements. In August 2018, the SEC adopted the final rule under SEC Release No. 33-10532, Disclosure Update and Simplification, amending certain disclosure requirements that were redundant, duplicative, overlapping, outdated or superseded. In addition, the amendments expanded the disclosure requirements on the analysis of stockholders' equity for interim financial statements. Under the amendments, an analysis of changes in each caption of stockholders' equity presented in the balance sheet must be provided in a note or separate statement. The analysis should present a reconciliation of the beginning balance to the ending balance of each period for which a statement of comprehensive income is required to be filed. This final rule was effective on November 5, 2018. The Company adopted this guidance in the first quarter of fiscal year 2019. Recent Accounting Pronouncements In June 2016, the FASB issued new guidance related to the accounting for credit losses on instruments for both financial services and non-financial services entities. The new guidance introduces an approach based on expected losses to estimate credit losses on certain types of financial instruments. It also modifies the impairment model for available-for-sale debt securities and provides for a simplified accounting model for purchased financial assets with credit deterioration since their origination. The guidance will be effective beginning January 1, 2020. Early adoption is permitted. The Company is currently evaluating the impact of this new guidance on its consolidated financial statements. In January 2017, the FASB issued new guidance to simplify the accounting for goodwill impairment. The guidance simplifies the measurement of goodwill impairment by removing step 2 of the goodwill impairment test, which requires the determination of the fair value of individual assets and liabilities of a reporting unit. The new guidance requires goodwill impairment to be measured as the amount by which a reporting unit’s carrying value exceeds its fair value; however, the loss recognized should not exceed the total amount of goodwill allocated to that reporting unit. The amendments should be applied on a prospective basis. The new standard is effective for fiscal years beginning after December 15, 2019 with early adoption permitted for interim or annual goodwill impairment tests performed after January 1, 2017. The Company is evaluating the impact of this new accounting guidance on its consolidated financial statements.
Fair Value of Fin. Instruments, Policy	Fair Value of Financial Instruments The Company’s cash, cash equivalents and short-term investments are carried at their fair values with any differences from their amortized cost recorded in equity as unrealized gains (losses) on marketable securities. As a basis for determining the fair value of its assets and liabilities, the Company follows a three-tier fair value hierarchy, which prioritizes the inputs used in measuring fair value as follows: (Level 1) observable inputs such as quoted prices in active markets; (Level 2) inputs other than the quoted prices in active markets that are observable either directly or indirectly; and (Level 3) unobservable inputs in which there is little or no market data which requires the Company to develop its own assumptions. This hierarchy requires the Company to use observable market data, when available, and to minimize the use of unobservable inputs when determining fair value. During the six months ended June 30, 2019 , there have been no transfers between Level 1 and Level 2 fair value instruments and no transfers in or out of Level 3. The Company’s money market funds are classified within Level 1 of the fair value hierarchy because they are valued using quoted market prices. The fair value of the Company’s Level 2 fixed income securities is obtained from independent pricing services, which may use quoted market prices for identical or comparable instruments or model-driven valuations using observable market data or other inputs, corroborated by observable market data. The Company does not have any financial instruments which are valued using Level 3 inputs.
Goodwill, Policy	Goodwill As of June 30, 2019 and December 31, 2018 , the Company had $49.2 million and $49.2 million of goodwill, respectively, with $41.2 million and $8.0 million allocated to the Company’s Product and Services operating segments, respectively. As of June 30, 2019
Intangible Assets, Policy	Intangible Assets Acquisition-related intangible assets are amortized either straight-line, or over the life of the assets on a basis that resembles the economic benefit of the assets. This yields amortization in the latter case that is higher in earlier periods of the useful life.
Purchase commitments	Non-cancelable Material Commitments The Company is required to purchase unused, non-cancelable, non-returnable raw material inventory that was purchased by its contract manufacturers based on committed finished goods orders from the Company, certain long lead-time raw materials based on the Company’s forecast and current work-in-progress materials. As of June 30, 2019 and December 31, 2018 , approximately $11.5 million and $11.1 million , respectively, of such inventory was purchased and held by the third-party manufacturers which was subject to these purchase guarantees.
Operating leases	Leases The Company determines if an arrangement is a lease at inception. Operating leases are included in other long-term assets, accrued payroll and other current liabilities and other long-term liabilities on the consolidated balance sheets. Sales-type leases are included in other receivables, accrued payroll and other current liabilities and other long-term liabilities on the consolidated balance sheets. The Company has elected an accounting policy to not recognize short-term leases (one year or less) on the consolidated balance sheet. The Company also elected the package of practical expedients which applies to leases that commenced before the adoption date. By electing the package of practical expedients, the Company did not need to reassess whether any existing contracts are or contained a lease or the lease classification for any existing leases. Operating lease right of use assets and operating lease liabilities are recognized based on the present value of the lease payments over the lease term at commencement date. As most of the Company’s leases do not provide an implicit rate, the incremental borrowing rate is used based on the information available at commencement date in determining the present value of future payments. The operating lease right of use asset also includes any lease payments made and excludes lease incentives. Lease terms may include options to extend or terminate the lease when it is reasonably certain that the Company will exercise that option. Lease expense for minimum lease payments is recognized on a straight-line basis over the lease term. The Company accounts for lease components and nonlease components as a single lease component.
Segment Reporting, Policy	The Company has two operating segments, which are both reportable business segments: (i) Product and (ii) Service, both of which are comprised of Vocera and its wholly-owned subsidiaries’ results of operations.
Revenue Recognition	The Company utilizes a five-step approach to recognizing revenue which depicts the transfer of promised goods or services to customers in an amount that reflects the consideration to which the entity expects to be entitled in exchange for those goods or services. • Identification of the contract, or contracts, with a customer - A contract with a customer exists when (i) the Company enters into an enforceable contract with a customer that defines each party’s rights regarding the goods or services to be transferred and identifies the payment terms related to these goods or services, (ii) the contract has commercial substance and, (iii) the Company determines that collection of substantially all consideration for goods or services that are transferred is probable based on the customer’s intent and ability to pay the promised consideration. The Company applies judgment in determining the customer’s ability and intention to pay, which is based on a variety of factors including the customer’s historical payment experience or, in the case of a new customer, published credit and financial information pertaining to the customer. Customer payments received by the Company are non-refundable. • Identification of the performance obligations in the contract - Performance obligations promised in a contract are identified based on the goods or services that will be transferred to the customer that are capable of being both: a) functionally distinct, whereby the customer can benefit from the goods or service either on their own or together with other resources that are readily available from third parties or from the Company, and b) contractually distinct, whereby the transfer of the goods or services is separately identifiable from other promises in the contract. To the extent a contract includes multiple promised goods or services, the Company applies judgment to determine whether promised goods or services are capable of being distinct and distinct in the context of the contract. If these criteria are not met the promised goods or services are accounted for as a combined performance obligation. • Determination of the transaction price - The transaction price is determined based on the consideration to which the Company will be entitled in exchange for transferring goods or services to the customer. • Allocation of the transaction price to the performance obligations in the contract - If the contract contains a single performance obligation, the entire transaction price is allocated to the single performance obligation. Contracts that contain multiple performance obligations require an allocation of the transaction price to each performance obligation based on a relative standalone selling price, or SSP, basis. The Company determines standalone selling price based on the price at which the performance obligation is sold separately. If the standalone selling price is not observable through past transactions, the Company estimates the standalone selling price taking into account available information such as market conditions and internally approved pricing guidelines related to the performance obligations. • Recognition of revenue when, or as, the Company satisfies a performance obligation - The Company satisfies performance obligations either over time or at a point in time as discussed in further detail below. Revenue is recognized at the time the related performance obligation is satisfied by transferring a promised good or service to a customer. Disaggregation of Revenue A typical sales arrangement involves performance obligations, such as the sales of the Company’s proprietary communication Vocera Badge, perpetual software licenses, professional services, and maintenance and support services which entitle customers to unspecified upgrades, patch releases and telephone-based support. The following table depicts the disaggregation of revenue according to revenue type and is consistent with how the Company evaluates its financial performance: Three months ended June 30, Six months ended June 30, (in thousands) 2019 2018 2019 2018 Product revenue Device $ 14,504 $ 15,049 $ 24,564 $ 27,697 Software 8,628 6,775 12,571 15,214 Total product 23,132 21,824 37,135 42,911 Service revenue Maintenance and support 16,928 15,505 33,321 29,470 Professional services and training 4,699 5,357 9,612 10,547 Total service 21,627 20,862 42,933 40,017 Total revenue $ 44,759 $ 42,686 $ 80,068 $ 82,928 Device revenue - In transactions where the Company delivers hardware, the Company considers itself to be the principal in the transaction and records revenue and costs of goods sold on a gross basis. Hardware revenue is generally recognized upon transfer of control to the customer. Software revenue - Revenue from the Company’s software products is generally recognized upon transfer of control to the customer. Maintenance and support revenue - The Company generates maintenance and support revenue primarily from post contract support (PCS) contracts, and, to a lesser extent, from sales of extended warranties on the Vocera Badge. The majority of software sales are in conjunction with PCS contracts, which generally have one-year terms. The Company recognizes revenue from PCS contracts ratably over the contractual service period. The service period typically commences upon transfer of control of the corresponding software products to the customer. The Company recognizes revenue from extended warranty contracts ratably over their contractual service period, which is typically one year. This period starts one year from the date on which the transfer of control on the underlying hardware occurs because the hardware generally carries a one-year warranty. Professional services and training revenue - Professional services and training revenue is generated when the Company installs and configures its software and devices at new or existing customer sites. The Company recognizes revenue related to professional services as they are performed. Contracts with multiple performance obligations - Some of the Company’s contracts with customers contain multiple performance obligations. For these contracts, the Company accounts for individual performance obligations separately if they are distinct. The transaction price is allocated to the separate performance obligations on a relative stand-alone selling price basis. For deliverables that are routinely sold separately, such as maintenance and support on the core offerings, the Company determines SSP by evaluating renewals over the trailing 12-months. For those that are not sold routinely, the Company determines SSP based on its overall pricing trends and objectives, taking into consideration market conditions and other factors, including the value of the contracts and the products sold. Contract balances - The timing of revenue recognition may differ from the timing of invoicing to customers. Accounts receivable are recorded at the invoiced amount. A receivable is recognized in the period the Company delivers goods or provides services or when the right to consideration is unconditional. Payment terms on invoiced amounts are typically 30 days. The balance of accounts receivable, net of allowance for doubtful accounts, as of June 30, 2019 and December 31, 2018 is presented in the accompanying consolidated balance sheets. As of June 30, 2019 and December 31, 2018 contract assets totaling $3.4 million and $2.4 million , respectively, were included in prepaid and other current assets in the condensed consolidated balance sheets. Costs to obtain and fulfill a contract - The Company capitalizes certain incremental contract acquisition costs consisting primarily of commissions paid and the related payroll taxes when customer contracts are signed. The Company determines whether costs should be deferred based on its sales compensation plans, if the commissions are incremental and would not have been incurred absent the execution of the customer contract. Sales commissions for renewals of customer contracts are not commensurate with the commissions paid for the acquisition of the initial contract given the substantive difference in commission rates in proportion to their respective contract values. Commissions paid upon the initial acquisition of a contract are amortized over the estimated period of benefit, which may exceed the term of the initial contract. Accordingly, amortization of deferred costs is recognized on a systematic basis that is consistent with the pattern of revenue recognition allocated to each performance obligation and is included in sales and marketing expense in the condensed consolidated statements of operations. The Company determines its estimated period of benefit by evaluating the expected renewals of its customer contracts, the duration of its relationships with its customers and other factors. Deferred costs are periodically reviewed for impairment. Changes in the balance of total deferred commissions (contract asset) during the three and six months ended June 30, 2019 are as follows: (in thousands) March 31, 2019 Additions Commissions Recognized June 30, 2019 Deferred commissions $ 10,322 $ 1,674 $ (2,078 ) $ 9,918 (in thousands) December 31, 2018 Additions Commissions Recognized June 30, 2019 Deferred commissions $ 10,303 $ 3,401 $ (3,786 ) $ 9,918 Of the $9.9 million total deferred commissions balance as of June 30, 2019 , the Company expects to recognize approximately 47% as commission expense over the next 12 months and the remainder thereafter. Deferred revenue - The Company records deferred revenue when cash payments are received in advance of the performance under the contract. The current portion of deferred revenue represents the amounts that are expected to be recognized as revenue within one year of the consolidated balance sheet date. Changes in the balance of total deferred revenue (contract liability) during the three and six months ended June 30, 2019 are as follows: (in thousands) March 31, 2019 Additions Revenue Recognized June 30, 2019 Deferred revenue $ 52,945 $ 18,264 $ (18,604 ) $ 52,605 (in thousands) December 31, 2018 Additions Revenue Recognized June 30, 2019 Deferred revenue $ 58,632 $ 33,182 $ (39,209 ) $ 52,605 Revenue recognized during the three and six months ended June 30, 2019 from deferred revenue balances at the beginning of the period was $17.0 million and $29.4 million , respectively. Revenue recognized during the three and six months ended June 30, 2018 from deferred revenue balances at the beginning of the period was $15.5 million and $27.1 million , respectively. The majority of the Company’s “contracted but not recognized” performance obligations are not subject to cancellation terms. The Company’s “contracted but not recognized” revenue, which represents revenue allocated to performance obligations for revenue contracted, and which includes deferred revenue and non-cancelable amounts that will be invoiced and recognized as revenue in future periods, was $116.4 million as of June 30, 2019 , of which the Company expects to recognize approximately 62% as revenue over the next 12 months and the remainder thereafter.

Revenue, deferred revenue, an_2

Revenue, deferred revenue, and deferred commissions (Tables)	6 Months Ended
	Jun. 30, 2019
Revenue from Contract with Customer [Abstract]
Disaggregation of Revenue	The following table depicts the disaggregation of revenue according to revenue type and is consistent with how the Company evaluates its financial performance: Three months ended June 30, Six months ended June 30, (in thousands) 2019 2018 2019 2018 Product revenue Device $ 14,504 $ 15,049 $ 24,564 $ 27,697 Software 8,628 6,775 12,571 15,214 Total product 23,132 21,824 37,135 42,911 Service revenue Maintenance and support 16,928 15,505 33,321 29,470 Professional services and training 4,699 5,357 9,612 10,547 Total service 21,627 20,862 42,933 40,017 Total revenue $ 44,759 $ 42,686 $ 80,068 $ 82,928
Contract with Customer, Asset and Liability	hanges in the balance of total deferred revenue (contract liability) during the three and six months ended June 30, 2019 are as follows: (in thousands) March 31, 2019 Additions Revenue Recognized June 30, 2019 Deferred revenue $ 52,945 $ 18,264 $ (18,604 ) $ 52,605 (in thousands) March 31, 2019 Additions Commissions Recognized June 30, 2019 Deferred commissions $ 10,322 $ 1,674 $ (2,078 ) $ 9,918

Fair Value of Financial Insturm

Fair Value of Financial Insturments (Tables)	6 Months Ended
	Jun. 30, 2019
Fair Value Disclosures [Abstract]
Assets and Liabilities Measured at Fair Value on a Recurring Basis	The Company’s assets that are measured at fair value on a recurring basis, by level, within the fair value hierarchy as of June 30, 2019 and December 31, 2018 , are summarized as follows (in thousands): June 30, 2019 December 31, 2018 Level 1 Level 2 Total Level 1 Level 2 Total Assets Money market funds $ 3,630 $ — $ 3,630 $ 3,737 $ — $ 3,737 Commercial paper — 39,945 39,945 — 16,570 16,570 U.S. government agency securities — 1,269 1,269 — 3,325 3,325 U.S. Treasury securities — 240 240 — 2,730 2,730 Corporate debt securities — 161,020 161,020 — 166,759 166,759 Total assets measured at fair value $ 3,630 $ 202,474 $ 206,104 $ 3,737 $ 189,384 $ 193,121

Cash, Cash Equivalents and Sh_2

Cash, Cash Equivalents and Short-term Investments (Tables)	6 Months Ended
	Jun. 30, 2019
Cash and Cash Equivalents [Abstract]
Schedule of Cash, Cash Equivalents and Available-For-Sale Investments	The following tables present cash, cash equivalents and short-term investments (in thousands) as of June 30, 2019 and December 31, 2018 : As of June 30, 2019 Amortized Cost Unrealized Gains Unrealized Losses Fair value Cash and cash equivalents: Demand deposits and other cash $ 9,284 $ — $ — $ 9,284 Money market funds 3,630 — — 3,630 Commercial paper 31,994 — (7 ) 31,987 Total cash and cash equivalents 44,908 — (7 ) 44,901 Short-Term Investments: Commercial paper 7,950 8 — 7,958 U.S. government agency securities 1,270 — (1 ) 1,269 U.S. Treasury securities 240 — — 240 Corporate debt securities 160,447 585 (12 ) 161,020 Total short-term investments 169,907 593 (13 ) 170,487 Total cash, cash equivalents and short-term investments $ 214,815 $ 593 $ (20 ) $ 215,388 As of December 31, 2018 Amortized Cost Unrealized Gains Unrealized Losses Fair value Cash and cash equivalents: Demand deposits and other cash $ 28,049 $ — $ — $ 28,049 Money market funds 3,737 — — 3,737 Commercial paper 2,491 — (1 ) 2,490 Total cash and cash equivalents 34,277 — (1 ) 34,276 Short-Term Investments: Commercial paper 14,091 — (11 ) 14,080 U.S. government agency securities 3,339 — (14 ) 3,325 U.S. Treasury securities 2,740 — (10 ) 2,730 Corporate debt securities 167,110 28 (379 ) 166,759 Total short-term investments 187,280 28 (414 ) 186,894 Total cash, cash equivalents and short-term investments $ 221,557 $ 28 $ (415 ) $ 221,170
Investments Classified by Contractual Maturity Date	Classification of the cash, cash equivalents and short-term investments by contractual maturity was as follows: (in thousands) One year or shorter Between 1 and 2 years Total Balances as of June 30, 2019 Cash and cash equivalents (1) $ 44,901 $ — $ 44,901 Short-term investments 108,573 61,914 170,487 Cash, cash equivalents and short-term investments $ 153,474 $ 61,914 $ 215,388 Balances as of December 31, 2018 Cash and cash equivalents (1) $ 34,276 $ — $ 34,276 Short-term investments 109,451 77,443 186,894 Cash, cash equivalents and short-term investments $ 143,727 $ 77,443 $ 221,170 (1) Includes demand deposits and other cash, money market funds and other cash equivalent securities, all with 0-90 day maturity at purchase.

Net Loss Per Share (Tables)

Net Loss Per Share (Tables)	6 Months Ended
	Jun. 30, 2019
Earnings Per Share [Abstract]
Schedule of the computation of basic and diluted net income (loss) per share	The following table sets forth the computation of basic and diluted net loss per share (in thousands, except per share amounts): Three months ended June 30, Six months ended June 30, 2019 2018 2019 2018 Numerator: Net loss $ (4,857 ) $ (3,554 ) $ (16,592 ) $ (8,324 ) Denominator: Weighted average shares used to compute net loss per common share - basic and diluted 31,242 29,867 31,022 29,673 Net loss per share Basic $ (0.16 ) $ (0.12 ) $ (0.53 ) $ (0.28 ) Diluted $ (0.16 ) $ (0.12 ) $ (0.53 ) $ (0.28 )
Schedule of antidilutive securities excluded from computation of earnings per share	The following securities were not included in the calculation of diluted shares outstanding as the effect would have been anti-dilutive: Three months ended June 30, Six months ended June 30, (in thousands) 2019 2018 2019 2018 Options to purchase common stock, including ESPP 656 1,236 690 1,283 Restricted stock units 1,671 1,955 1,760 1,991

Goodwill and Intangible Assets

Goodwill and Intangible Assets (Tables)	6 Months Ended
	Jun. 30, 2019
Goodwill and Intangible Assets Disclosure [Abstract]
Schedule of Finite-Lived Intangible Assets	The estimated useful lives and carrying value of acquired intangible assets are as follows: June 30, 2019 December 31, 2018 (in thousands) Range of Useful Life (years) Gross Carrying Amount Accumulated Amortization Net Carrying Amount Gross Carrying Amount Accumulated Amortization Net Carrying Amount Developed technology 3 to 7 $ 10,050 $ 8,945 $ 1,105 $ 10,050 $ 7,731 $ 2,319 Customer relationships 7 to 9 10,920 5,249 5,671 10,920 4,645 6,275 Backlog 3 1,400 1,249 151 1,400 1,203 197 Non-compete agreements 2 to 4 460 460 — 460 460 — Trademarks 3 to 7 1,110 999 111 1,110 831 279 Intangible assets, net book value $ 23,940 $ 16,902 $ 7,038 $ 23,940 $ 14,870 $ 9,070
Schedule of Finite-Lived Intangible Assets, Future Amortization Expense	Amortization of acquired intangible assets is reflected in the cost of revenue for developed technology and backlog and in operating expenses for the other intangible assets. The estimated future amortization of existing acquired intangible assets as of June 30, 2019 was as follows: (in thousands) Future amortization 2019 (remaining six months) $ 1,691 2020 1,242 2021 1,130 2022 1,050 2023 1,050 2024 875 Future amortization expense $ 7,038

Balance Sheet Components (Table

Balance Sheet Components (Tables)	6 Months Ended
	Jun. 30, 2019
Balance Sheet Components [Abstract]
Inventories	Inventories (in thousands) June 30, December 31, Raw materials $ 197 $ 197 Finished goods 4,987 4,153 Total inventories $ 5,184 $ 4,350
Property and Equipment	Property and equipment, net (in thousands) June 30, December 31, Computer equipment and software $ 11,692 $ 10,433 Furniture, fixtures and equipment 2,279 2,246 Leasehold improvements 5,140 5,183 Manufacturing tools and equipment 2,534 2,371 Construction in process 410 520 Property and equipment, at cost 22,055 20,753 Less: Accumulated depreciation (14,633 ) (13,285 ) Property and equipment, net $ 7,422 $ 7,468 Depreciation and amortization expense was $0.9 million and $0.8 million for the three months ended June 30, 2019 and 2018 , respectively. Depreciation and amortization expense was $1.8 million and $1.5 million for the six months ended June 30, 2019 and 2018 , respectively.
Schedule of Components of Leveraged Lease Investments	Net investment in sales-type leases The Company has sales-type leases with terms of 3 to 4 years. Sales-type lease receivables are collateralized by the underlying equipment. The components of the Company’s net investment in sales-type leases are as follows: (in thousands) June 30, December 31, Minimum payments to be received on sales-type leases $ 2,612 $ 2,111 Less: Unearned interest income and executory revenue portion (1,326 ) (1,387 ) Net investment in sales-type leases 1,286 724 Less: Current portion (742 ) (427 ) Non-current net investment in sales-type leases $ 544 $ 297 Sales-type lease activity recognized in the consolidated statement of operations are as follows: Three months ended June 30, Six months ended June 30, (in thousands) 2019 2018 2019 2018 Lease revenue $ 2,703 $ 491 $ 3,364 $ 1,500 Less: Cost of lease shipments (805 ) (91 ) (857 ) (228 ) Gross profit 1,898 400 2,507 1,272 Interest income (expense), net on lease receivable 3 — — (1 ) Initial direct cost incurred 109 26 140 72 There were no allowances for doubtful accounts on these leases as of June 30, 2019 and December 31, 2018 . There is no guaranteed or unguaranteed residual value on the leased equipment. The current and non-current net investments in sales-type leases are reported as components of the consolidated balance sheet captions “other receivables” and “other long-term assets,” respectively.
Schedule of Future Minimum Lease Payments for Capital Leases	The minimum payments expected to be received for future years under sales-type leases as of June 30, 2019 were as follows: (in thousands) Future lease payments 2019 (remaining six months) $ 629 2020 1,049 2021 518 2022 338 2023 78 Total $ 2,612
Accrued Liabilities	Accrued payroll and other current liabilities (in thousands) June 30, December 31, Payroll and related expenses $ 5,946 $ 7,241 Accrued payables 2,214 2,115 Operating lease liabilities, current portion 1,997 — Lease financing, current portion 961 956 Product warranty 355 376 Customer prepayments 376 629 Sales and use tax payable 336 379 Other 717 1,189 Total accrued payroll and other current liabilities $ 12,902 $ 12,885
Schedule of Product Warranty Liability	The changes in the Company’s product warranty reserve are as follows: Three months ended June 30, Six months ended June 30, (in thousands) 2019 2018 2019 2018 Warranty balance at the beginning of the period $ 374 $ 303 $ 376 $ 353 Warranty expense accrued for shipments during the period 92 129 169 215 Changes in estimate related to pre-existing warranties (55 ) (75 ) (86 ) (134 ) Warranty settlements made (56 ) (51 ) (104 ) (128 ) Total product warranty $ 355 $ 306 $ 355 $ 306
Information Related to Leases	Supplemental balance sheet information related to leases was as follows: (in thousands) June 30, Other long-term assets $ 5,409 Accrued payroll and other current liabilities 1,997 Other long-term liabilities 4,576 Total operating lease liabilities $ 6,573 Other information related to leases was as follows: Three months ended June 30, Six months ended June 30, (in thousands) 2019 2019 Supplemental Cash Flow Information Cash paid for amounts included in the measurement of lease liabilities $ 634 $ 1,264 Right-of-use assets obtained in exchange for lease obligations $ 329 $ 1,018 Weighted average remaining lease term 2.84 years 2.84 years Weighted average discount rate 8 % 8 %

Convertible Senior Notes (Table

Convertible Senior Notes (Tables)	6 Months Ended
	Jun. 30, 2019
Debt Disclosure [Abstract]
Schedule of Notes	The Notes consist of the following: (in thousands) June 30, December 31, Liability: Principal $ 143,750 $ 143,750 Unamortized debt discount (26,953 ) (29,846 ) Unamortized issuance costs (3,038 ) (3,364 ) Net carrying amount $ 113,759 $ 110,540 Stockholders’ equity: Debt discount for conversion option $ 33,350 $ 33,350 Issuance costs $ (1,136 ) $ (1,136 ) Net carrying amount $ 32,214 $ 32,214
Schedule of Interest Expense Related to the Notes	Interest expense related to the Notes is as follows: Three months ended June 30, Six months ended June 30, (in thousands) 2019 2018 2019 2018 Contractual interest expense $ 539 $ 264 $ 1,078 $ 264 Amortization of debt discount 1,471 659 2,893 659 Amortization of issuance costs 166 74 326 74 Total interest expense $ 2,176 $ 997 $ 4,297 $ 997
Schedule of Net Impact on Stockholders' Equity of Components of Convertible Debt	The net impact to the Company’s stockholders' equity, included in additional paid-in capital, of the above components of the Notes is as follows: (in thousands) June 30, Conversion option $ 33,350 Purchase of capped calls $ (8,907 ) Issuance costs $ (1,136 ) Total $ 23,307

Stock-based Compensation and _2

Stock-based Compensation and Awards (Tables)	6 Months Ended
	Jun. 30, 2019
Disclosure of Compensation Related Costs, Share-based Payments [Abstract]
Rollforward of stock option activity	A summary of the stock option activity for the six months ended June 30, 2019 is presented below: Options Outstanding Number of options Weighted average exercise price Weighted average remaining contractual term Aggregate intrinsic value (in years) (in thousands) Outstanding at December 31, 2018 797,501 $ 13.31 4.71 $ 20,767 Options granted — — Options exercised (159,615 ) 13.10 Options canceled — — Outstanding at June 30, 2019 637,886 $ 13.36 4.11 $ 11,838
Equity B-S-M Valuation Assumptions	The following Black-Scholes option-pricing assumptions were used for each respective period for the ESPP: Three months ended June 30, Six months ended June 30, 2019 2018 2019 2018 Expected term (in years) 0.50 0.50 0.50 0.50 Volatility 33% - 45.2% 29% - 37.8% 33% - 45.2% 29% - 37.8% Risk-free interest rate 2.43% - 2.51% 1.39% - 2.09% 2.43% - 2.51% 1.39% - 2.09% Dividend yield 0% 0% 0% 0%
Rollforward of RSA and RSU activty	A summary of RSU activity for the six months ended June 30, 2019 is presented below: Restricted Stock Units Number of shares Weighted Average Grant Date Fair Value per Share Outstanding at December 31, 2018 1,807,180 $ 23.13 Granted 728,625 33.25 Vested (804,810 ) 21.17 Forfeited (60,442 ) 25.86 Outstanding at June 30, 2019 1,670,553 $ 28.39
Allocation of Recognized Period Costs	The following table presents the allocation of stock-based compensation expense: Three months ended June 30, Six months ended June 30, (in thousands) 2019 2018 2019 2018 Cost of revenue $ 1,178 $ 966 $ 2,156 $ 1,713 Research and development 1,034 755 1,856 1,362 Sales and marketing 1,758 1,655 3,478 3,151 General and administrative 2,139 2,020 4,163 3,757 Total stock-based compensation $ 6,109 $ 5,396 $ 11,653 $ 9,983

Segments Segments (Tables)

Segments Segments (Tables)	6 Months Ended
	Jun. 30, 2019
Segment Reporting [Abstract]
Segments	The following table presents a summary of the operating segments: Three months ended June 30, Six months ended June 30, 2019 2018 2019 2018 (in thousands) Revenue Product $ 23,132 $ 21,824 $ 37,135 $ 42,911 Service 21,627 20,862 42,933 40,017 Total revenue 44,759 42,686 80,068 82,928 Cost of revenue Product 6,912 6,683 12,246 13,028 Service 10,831 10,352 21,121 20,348 Total cost of revenue 17,743 17,035 33,367 33,376 Gross profit Product 16,220 15,141 24,889 29,883 Service 10,796 10,510 21,812 19,669 Total gross profit 27,016 25,651 46,701 49,552 Operating expenses 30,956 28,765 61,701 57,460 Interest income (expense), net and other (997 ) (995 ) (1,708 ) (1,059 ) Loss before income taxes $ (4,937 ) $ (4,109 ) $ (16,708 ) $ (8,967 )

The Company and Summary of Si_3

The Company and Summary of Significant Accounting Policies Narrative (Details) - USD ($) $ in Thousands	Jun. 30, 2019	Jan. 01, 2019	Dec. 31, 2018
New Accounting Pronouncements or Change in Accounting Principle [Line Items]
Operating lease right of use asset	$ 5,409
Total operating lease liabilities	6,573
Net Investment in Sales Type Leases	$ 1,286		$ 724
Accounting Standards Update 2016-02 [Member]
New Accounting Pronouncements or Change in Accounting Principle [Line Items]
Operating lease right of use asset		$ 5,100
Total operating lease liabilities		$ 6,700

Revenue, deferred revenue, an_3

Revenue, deferred revenue, and deferred commissions - Consolidated Balance Sheet (Details) - USD ($) $ in Thousands	Jun. 30, 2019	Mar. 31, 2019	Dec. 31, 2018
Revenue, Initial Application Period Cumulative Effect Transition [Line Items]
Other receivables	$ 5,578		$ 4,148
Deferred revenue, current	42,303		44,053
Deferred revenue, long-term	10,302		14,579
Total deferred revenue	52,605	$ 52,945	58,632
Stockholders' equity	$ 152,480		$ 162,867

Revenue, deferred revenue, an_4

Revenue, deferred revenue, and deferred commissions - Consolidated Statement of Operations (Details) - USD ($) $ in Thousands	3 Months Ended				6 Months Ended
	Jun. 30, 2019	Mar. 31, 2019	Jun. 30, 2018	Mar. 31, 2018	Jun. 30, 2019	Jun. 30, 2018
Revenue
Total revenue	$ 44,759		$ 42,686
Gross Profit	27,016		25,651
Operating expenses	30,956		28,765
Operating Income (Loss)	(3,940)		(3,114)
Net loss	(4,857)	$ (11,735)	(3,554)	$ (4,770)	$ (16,592)	$ (8,324)
Product
Revenue
Total revenue	23,132		21,824
Service
Revenue
Total revenue	$ 21,627		$ 20,862

Revenue, deferred revenue, an_5

Revenue, deferred revenue, and deferred commissions - Cash Flows From Operating Activities (Details) - USD ($) $ in Thousands	3 Months Ended				6 Months Ended
	Jun. 30, 2019	Mar. 31, 2019	Jun. 30, 2018	Mar. 31, 2018	Jun. 30, 2019	Jun. 30, 2018
Revenue, Initial Application Period Cumulative Effect Transition [Line Items]
Net loss	$ (4,857)	$ (11,735)	$ (3,554)	$ (4,770)	$ (16,592)	$ (8,324)
Adjustments to reconcile net loss to net cash used in operating activities:
Deferred commissions					385	972
Deferred revenue					$ (6,027)	$ (1,742)

Revenue, deferred revenue, an_6

Revenue, deferred revenue, and deferred commissions - Disaggregation of Revenue (Details) - USD ($) $ in Thousands	3 Months Ended
	Jun. 30, 2019	Jun. 30, 2018
Revenue, Initial Application Period Cumulative Effect Transition [Line Items]
Total revenue	$ 44,759	$ 42,686
Product Segment [Member]
Revenue, Initial Application Period Cumulative Effect Transition [Line Items]
Total revenue	23,132	21,824
Product Segment [Member] | Software [Member]
Revenue, Initial Application Period Cumulative Effect Transition [Line Items]
Total revenue	8,628	6,775
Product Segment [Member] | Device [Member]
Revenue, Initial Application Period Cumulative Effect Transition [Line Items]
Total revenue	14,504	15,049
Service Segment [Member]
Revenue, Initial Application Period Cumulative Effect Transition [Line Items]
Total revenue	21,627	20,862
Service Segment [Member] | Maintenance and Support [Member]
Revenue, Initial Application Period Cumulative Effect Transition [Line Items]
Total revenue	16,928	15,505
Service Segment [Member] | Professional Services and Training [Member]
Revenue, Initial Application Period Cumulative Effect Transition [Line Items]
Total revenue	$ 4,699	$ 5,357

Revenue, deferred revenue, an_7

Revenue, deferred revenue, and deferred commissions - Significant Changes in Deferred Commissions (Details) - USD ($) $ in Thousands	3 Months Ended	6 Months Ended
	Jun. 30, 2019	Jun. 30, 2019
Change in Contract with Customer, Asset [Roll Forward]
Beginning balance	$ 10,322	$ 10,303
Additions	1,674	3,401
Commissions Recognized	(2,078)	(3,786)
Ending balance	$ 9,918	$ 9,918

Revenue, deferred revenue, an_8

Revenue, deferred revenue, and deferred commissions - Significant Changes in Deferred Revenue (Details) - USD ($) $ in Thousands	3 Months Ended		6 Months Ended
	Jun. 30, 2019	Jun. 30, 2018	Jun. 30, 2019	Jun. 30, 2018
Revenue from Contract with Customer [Abstract]
Revenue recognized pertaining to amounts deferred as of Beginning of Period	$ 17,000		$ 29,400
Revenue recognized pertaining to amounts deferred as of End of Period		$ 15,500		$ 27,100
Change in Contract with Customer, Liability [Roll Forward]
Beginning balance	52,945		58,632
Additions	18,264		33,182
Revenue Recognized	(18,604)		(39,209)
Ending balance	$ 52,605		$ 52,605

Revenue, deferred revenue, an_9

Revenue, deferred revenue, and deferred commissions - Narrative (Details) - USD ($) $ in Thousands	3 Months Ended		6 Months Ended
	Jun. 30, 2019	Jun. 30, 2018	Jun. 30, 2019	Jun. 30, 2018	Mar. 31, 2019	Dec. 31, 2018
Revenue from Contract with Customer [Abstract]
Payment terms on invoiced amounts			30 days
Deferred commissions	$ 9,918		$ 9,918		$ 10,322	$ 10,303
Percentage of deferred commissions to be recognized as commission expense in the next 12 months	47.00%		47.00%
Revenue recognized pertaining to amounts deferred as of Beginning of Period	$ 17,000		$ 29,400
Revenue recognized pertaining to amounts deferred as of End of Period		$ 15,500		$ 27,100
Deferred revenue and backlog	$ 116,400		$ 116,400
Percentage of deferred revenue to be recognized over the next 12 months	62.00%		62.00%
Contract with Customer, Asset, Gross	$ 3,400		$ 3,400			$ 2,400

Fair Value of Financial Instr_2

Fair Value of Financial Instruments (Details) - USD ($)	6 Months Ended
	Jun. 30, 2019	Dec. 31, 2018
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Fair Value, Assets, Level 2 to Level 1 Transfers, Amount	$ 0
Fair Value, Assets, Level 1 to Level 2 Transfers, Amount	0
Fair Value, Measurement with Unobservable Inputs Reconciliation, Recurring Basis, Asset Transfers Into Level 3	0
Fair Value, Measurement with Unobservable Inputs Reconciliation, Recurring Basis, Asset, Transfers out of Level 3	0
Assets, Fair Value Disclosure [Abstract]
Cash and cash equivalents	44,901,000	$ 34,276,000
Short-term investments	170,487,000	186,894,000
U.S. government agency securities
Assets, Fair Value Disclosure [Abstract]
Short-term investments	1,269,000	3,325,000
U.S. Treasury securities
Assets, Fair Value Disclosure [Abstract]
Short-term investments	240,000	2,730,000
Corporate debt securities
Assets, Fair Value Disclosure [Abstract]
Short-term investments	161,020,000	166,759,000
Fair Value, Measurements, Recurring
Assets, Fair Value Disclosure [Abstract]
Total assets measured at fair value	206,104,000	193,121,000
Fair Value, Measurements, Recurring | Level 1
Assets, Fair Value Disclosure [Abstract]
Total assets measured at fair value	3,630,000	3,737,000
Fair Value, Measurements, Recurring | Level 2
Assets, Fair Value Disclosure [Abstract]
Total assets measured at fair value	202,474,000	189,384,000
Fair Value, Measurements, Recurring | U.S. government agency securities
Assets, Fair Value Disclosure [Abstract]
Short-term investments	1,269,000	3,325,000
Fair Value, Measurements, Recurring | U.S. government agency securities | Level 1
Assets, Fair Value Disclosure [Abstract]
Short-term investments	0	0
Fair Value, Measurements, Recurring | U.S. government agency securities | Level 2
Assets, Fair Value Disclosure [Abstract]
Short-term investments	1,269,000	3,325,000
Fair Value, Measurements, Recurring | U.S. Treasury securities
Assets, Fair Value Disclosure [Abstract]
Short-term investments	240,000	2,730,000
Fair Value, Measurements, Recurring | U.S. Treasury securities | Level 1
Assets, Fair Value Disclosure [Abstract]
Short-term investments	0	0
Fair Value, Measurements, Recurring | U.S. Treasury securities | Level 2
Assets, Fair Value Disclosure [Abstract]
Short-term investments	240,000	2,730,000
Fair Value, Measurements, Recurring | Corporate debt securities
Assets, Fair Value Disclosure [Abstract]
Short-term investments	161,020,000	166,759,000
Fair Value, Measurements, Recurring | Corporate debt securities | Level 1
Assets, Fair Value Disclosure [Abstract]
Short-term investments	0	0
Fair Value, Measurements, Recurring | Corporate debt securities | Level 2
Assets, Fair Value Disclosure [Abstract]
Short-term investments	161,020,000	166,759,000
Fair Value, Measurements, Recurring | Money market funds
Assets, Fair Value Disclosure [Abstract]
Cash and cash equivalents	3,630,000	3,737,000
Fair Value, Measurements, Recurring | Money market funds | Level 1
Assets, Fair Value Disclosure [Abstract]
Cash and cash equivalents	3,630,000	3,737,000
Fair Value, Measurements, Recurring | Money market funds | Level 2
Assets, Fair Value Disclosure [Abstract]
Cash and cash equivalents	0	0
Fair Value, Measurements, Recurring | Commercial paper
Assets, Fair Value Disclosure [Abstract]
Short-term investments	39,945,000	16,570,000
Fair Value, Measurements, Recurring | Commercial paper | Level 1
Assets, Fair Value Disclosure [Abstract]
Short-term investments	0	0
Fair Value, Measurements, Recurring | Commercial paper | Level 2
Assets, Fair Value Disclosure [Abstract]
Short-term investments	$ 39,945,000	$ 16,570,000

Schedule of Available for Sale

Schedule of Available for Sale Securities (Details) - USD ($) $ in Thousands	Jun. 30, 2019	Dec. 31, 2018
Cash and cash equivalents [Abstract]
Cash and Cash Equivalents, Amortized Cost	$ 44,908	$ 34,277
Cash And Cash Equivalents, Gross Unrealized Gains	0	0
Cash And Cash Equivalents, Gross Unrealized Losses	(7)	(1)
Cash and cash equivalents	44,901	34,276
Short-term Investments [Abstract]
AFS Securities, Amortized Cost Basis	169,907	187,280
Debt Securities, Available-for-sale, Accumulated Gross Unrealized Gain, before Tax	593	28
Debt Securities, Available-for-sale, Accumulated Gross Unrealized Loss, before Tax	13	414
Short-term investments	170,487	186,894
Cash, Cash Equivalents, and Short-term Investments [Abstract]
Cash, Cash Equiv. And S-T Investments, Amortized Cost	214,815	221,557
Cash, Cash Equivalents And Short Term Investments, Unrealized Gains	593	28
Cash, Cash Equivalents And Short Term Investments, Unrealized Losses	20	415
Cash, cash equivalents and short-term investments	215,388	221,170
Demand deposits and other cash
Cash and cash equivalents [Abstract]
Cash and Cash Equivalents, Amortized Cost	9,284	28,049
Cash And Cash Equivalents, Gross Unrealized Gains	0	0
Cash And Cash Equivalents, Gross Unrealized Losses	0	0
Cash and cash equivalents	9,284	28,049
Money market funds
Cash and cash equivalents [Abstract]
Cash and Cash Equivalents, Amortized Cost	3,630	3,737
Cash And Cash Equivalents, Gross Unrealized Gains	0	0
Cash And Cash Equivalents, Gross Unrealized Losses	0	0
Cash and cash equivalents	3,630	3,737
Commercial Paper in CE
Cash and cash equivalents [Abstract]
Cash and Cash Equivalents, Amortized Cost	31,994	2,491
Cash And Cash Equivalents, Gross Unrealized Gains	0	0
Cash And Cash Equivalents, Gross Unrealized Losses	(7)	(1)
Cash and cash equivalents	31,987	2,490
Commercial paper in STI
Short-term Investments [Abstract]
AFS Securities, Amortized Cost Basis	7,950	14,091
Debt Securities, Available-for-sale, Accumulated Gross Unrealized Gain, before Tax	8	0
Debt Securities, Available-for-sale, Accumulated Gross Unrealized Loss, before Tax	0	11
Short-term investments	7,958	14,080
U.S. government agency securities
Short-term Investments [Abstract]
AFS Securities, Amortized Cost Basis	1,270	3,339
Debt Securities, Available-for-sale, Accumulated Gross Unrealized Gain, before Tax	0	0
Debt Securities, Available-for-sale, Accumulated Gross Unrealized Loss, before Tax	1	14
Short-term investments	1,269	3,325
U.S. Treasury securities
Short-term Investments [Abstract]
AFS Securities, Amortized Cost Basis	240	2,740
Debt Securities, Available-for-sale, Accumulated Gross Unrealized Gain, before Tax	0	0
Debt Securities, Available-for-sale, Accumulated Gross Unrealized Loss, before Tax	0	10
Short-term investments	240	2,730
Corporate Debt Securities
Short-term Investments [Abstract]
AFS Securities, Amortized Cost Basis	160,447	167,110
Debt Securities, Available-for-sale, Accumulated Gross Unrealized Gain, before Tax	585	28
Debt Securities, Available-for-sale, Accumulated Gross Unrealized Loss, before Tax	12	379
Short-term investments	$ 161,020	$ 166,759

Contractual maturities of cash,

Contractual maturities of cash, cash equivalent and short-term investment (Details) - USD ($) $ in Thousands	Jun. 30, 2019	Dec. 31, 2018
Debt Securities, Available-for-sale [Line Items]
Cash and cash equivalents	$ 44,901	$ 34,276
Short-term investments	170,487	186,894
Cash, cash equivalents and short-term investments	215,388	221,170
Maturity up to one year
Debt Securities, Available-for-sale [Line Items]
Cash and cash equivalents	44,901	34,276
Short-term investments	108,573	109,451
Cash, cash equivalents and short-term investments	153,474	143,727
maturity between 1 and 2 years [Member]
Debt Securities, Available-for-sale [Line Items]
Cash and cash equivalents	0	0
Short-term investments	61,914	77,443
Cash, cash equivalents and short-term investments	$ 61,914	$ 77,443

Schedule of the computation of

Schedule of the computation of basic and diluted net income (loss) per share (Details) - USD ($) $ / shares in Units, shares in Thousands, $ in Thousands	3 Months Ended				6 Months Ended
	Jun. 30, 2019	Mar. 31, 2019	Jun. 30, 2018	Mar. 31, 2018	Jun. 30, 2019	Jun. 30, 2018
Earnings Per Share [Abstract]
Weighted Average Number of Shares Outstanding, Diluted	31,242		29,867		31,022	29,673
Weighted Average Number of Shares Outstanding, Basic	31,242		29,867
Numerator:
Net loss	$ (4,857)	$ (11,735)	$ (3,554)	$ (4,770)	$ (16,592)	$ (8,324)
Net loss per share
Earnings Per Share, Basic	$ (0.16)		$ (0.12)		$ (0.53)	$ (0.28)
Earnings Per Share, Diluted	$ (0.16)		$ (0.12)		$ (0.53)	$ (0.28)

Schedule of antidilutive securi

Schedule of antidilutive securities excluded from computation of earnings per share (Details) - shares shares in Thousands	3 Months Ended
	Jun. 30, 2019	Jun. 30, 2018
Options to purchase common stock, including ESPP
Antidilutive Securities Excluded from Computation of Earnings Per Share [Line Items]
Antidilutive Securities Excluded from Computation of Earnings Per Share, Amount	656	1,236
Restricted stock units
Antidilutive Securities Excluded from Computation of Earnings Per Share [Line Items]
Antidilutive Securities Excluded from Computation of Earnings Per Share, Amount	1,671	1,955

Schedule of Finite-Lived Intang

Schedule of Finite-Lived Intangible Assets (Details) - USD ($) $ in Thousands	6 Months Ended
	Jun. 30, 2019	Dec. 31, 2018
Finite-Lived Intangible Assets [Line Items]
Finite-Lived Intangible Assets, Amortization Expense, Year Two	$ 1,242
Finite-Lived Intangible Assets, Amortization Expense, Year Three	1,130
Finite-Lived Intangible Assets, Amortization Expense, Year Four	1,050
Finite-Lived Intangibles, Amortization Expense, Year Five	1,050
Finite-Lived Intangibles, AmortExp Remainder 2018	1,691
Accumulated Amortization	16,902	$ 14,870
Finite-Lived Intangible Assets, Net	7,038
Finite-Lived Intangible Assets, Useful Life
Intangible assets, gross	23,940	23,940
Intangible assets, net book value	7,038	9,070
Developed technology
Finite-Lived Intangible Assets [Line Items]
Gross Carrying Amount	10,050	10,050
Accumulated Amortization	8,945	7,731
Finite-Lived Intangible Assets, Net	1,105	2,319
Customer relationships
Finite-Lived Intangible Assets [Line Items]
Gross Carrying Amount	10,920	10,920
Accumulated Amortization	5,249	4,645
Finite-Lived Intangible Assets, Net	5,671	6,275
Order or Production Backlog [Member]
Finite-Lived Intangible Assets [Line Items]
Gross Carrying Amount	1,400	1,400
Accumulated Amortization	1,249	1,203
Finite-Lived Intangible Assets, Net	151	197
Noncompete Agreements
Finite-Lived Intangible Assets [Line Items]
Gross Carrying Amount	460	460
Accumulated Amortization	460	460
Finite-Lived Intangible Assets, Net	0	0
Trademarks
Finite-Lived Intangible Assets [Line Items]
Gross Carrying Amount	1,110	1,110
Accumulated Amortization	999	831
Finite-Lived Intangible Assets, Net	$ 111	$ 279
Minimum | Developed technology
Finite-Lived Intangible Assets, Useful Life
Finite-lived intangible asset, useful life	3 years
Minimum | Customer relationships
Finite-Lived Intangible Assets, Useful Life
Finite-lived intangible asset, useful life	7 years
Minimum | Order or Production Backlog [Member]
Finite-Lived Intangible Assets, Useful Life
Finite-lived intangible asset, useful life	3 years
Minimum | Noncompete Agreements
Finite-Lived Intangible Assets, Useful Life
Finite-lived intangible asset, useful life	2 years
Minimum | Trademarks
Finite-Lived Intangible Assets, Useful Life
Finite-lived intangible asset, useful life	3 years
Maximum | Developed technology
Finite-Lived Intangible Assets, Useful Life
Finite-lived intangible asset, useful life	7 years
Maximum | Customer relationships
Finite-Lived Intangible Assets, Useful Life
Finite-lived intangible asset, useful life	9 years
Maximum | Order or Production Backlog [Member]
Finite-Lived Intangible Assets, Useful Life
Finite-lived intangible asset, useful life	3 years
Maximum | Noncompete Agreements
Finite-Lived Intangible Assets, Useful Life
Finite-lived intangible asset, useful life	4 years
Maximum | Trademarks
Finite-Lived Intangible Assets, Useful Life
Finite-lived intangible asset, useful life	7 years

Future amortization schedule (D

Future amortization schedule (Details) $ in Thousands	Jun. 30, 2019USD ($)
Goodwill and intangible assets [Abstract]
Finite-Lived Intangibles, AmortExp Remainder 2018	$ 1,691
Finite-Lived Intangible Assets, Amortization Expense, Year Two	1,242
Finite-Lived Intangible Assets, Amortization Expense, Year Three	1,130
Finite-Lived Intangible Assets, Amortization Expense, Year Four	1,050
Finite-Lived Intangibles, Amortization Expense, Year Five	1,050
Finite-Lived Intangibles, AmortExp, after 2023	875
Finite-Lived Intangible Assets, Net	$ 7,038

Goodwill and Intangible Asset_2

Goodwill and Intangible Assets Narrative (Details) - USD ($) $ in Thousands	3 Months Ended		6 Months Ended
	Jun. 30, 2019	Jun. 30, 2018	Jun. 30, 2019	Jun. 30, 2018	Dec. 31, 2018
Finite-Lived Intangible Assets [Line Items]
Goodwill	$ 49,246		$ 49,246		$ 49,246
Intangibles - period amortization expense [Abstract]
Amortization expense	1,000	$ 1,000	2,000	$ 2,300
Product Segment [Member]
Finite-Lived Intangible Assets [Line Items]
Goodwill	41,200		41,200
Service Segment [Member]
Finite-Lived Intangible Assets [Line Items]
Goodwill	$ 8,000		$ 8,000

Inventories (Details)

Inventories (Details) - USD ($) $ in Thousands	Jun. 30, 2019	Dec. 31, 2018
Inventory, Net [Abstract]
Raw materials	$ 197	$ 197
Finished goods	4,987	4,153
Total inventories	$ 5,184	$ 4,350

Property and Equipment (Details

Property and Equipment (Details) - USD ($) $ in Thousands	3 Months Ended		6 Months Ended
	Jun. 30, 2019	Jun. 30, 2018	Jun. 30, 2019	Jun. 30, 2018	Dec. 31, 2018
Property, Plant and Equipment [Line Items]
Property, Plant and Equipment, Gross	$ 22,055		$ 22,055		$ 20,753
Less: Accumulated depreciation	(14,633)		(14,633)		(13,285)
Property and equipment, net	7,422		7,422		7,468
Depreciation, Depletion and Amortization [Abstract]
Depreciation	900	$ 800	1,800	$ 1,500
Computer equipment and software
Property, Plant and Equipment [Line Items]
Property, Plant and Equipment, Gross	11,692		11,692		10,433
Furniture, fixtures and equipment
Property, Plant and Equipment [Line Items]
Property, Plant and Equipment, Gross	2,279		2,279		2,246
Leasehold improvements
Property, Plant and Equipment [Line Items]
Property, Plant and Equipment, Gross	5,140		5,140		5,183
Manufacturing tools and equipment
Property, Plant and Equipment [Line Items]
Property, Plant and Equipment, Gross	2,534		2,534		2,371
Construction in process
Property, Plant and Equipment [Line Items]
Property, Plant and Equipment, Gross	$ 410		$ 410		$ 520

Investment in Sales Type Leases

Investment in Sales Type Leases (Details) - USD ($) $ in Thousands	6 Months Ended
	Jun. 30, 2019	Dec. 31, 2018
Capital Leased Assets [Line Items]
Net Investment in Sales Type Leases, Future Minimum Payments-Gross	$ 2,612	$ 2,111
Net Investment in Sales Type Leases, Deferred Income	(1,326)	(1,387)
Net Investment in Sales Type Leases	1,286	724
Net Investment in Sales Type Leases, Current	(742)	(427)
Net Investment in Sales Type Leases, Noncurrent	$ 544	$ 297
Minimum
Capital Leased Assets [Line Items]
Lessors, Capital Leases, Term of contract	3 years
Maximum
Capital Leased Assets [Line Items]
Lessors, Capital Leases, Term of contract	4 years

Balance Sheet Components Sales

Balance Sheet Components Sales Type Lease Activity (Details) - USD ($) $ in Thousands	3 Months Ended		6 Months Ended
	Jun. 30, 2019	Jun. 30, 2018	Jun. 30, 2019	Jun. 30, 2018
Balance Sheet Components [Abstract]
Lease revenue	$ 2,703	$ 491	$ 3,364	$ 1,500
Less: Cost of lease shipments	(805)	(91)	(857)	(228)
Gross profit	1,898	400	2,507	1,272
Sales-type Lease, Interest Income, Lease Receivable	3	0	0	1
Initial cost expensed	$ 109	$ 26	$ 140	$ 72

Future payments- sales type lea

Future payments- sales type leases (Details) - USD ($) $ in Thousands	Jun. 30, 2019	Dec. 31, 2018
Balance Sheet Components [Abstract]
Future Minimum Payments, Remainder of Fiscal Year	$ 629
Capital Leases, Future Minimum Payments Due in Two Years	1,049
Sales-type Leases, Future Minimum Payments Due in 2021	518
Capital Leases, Future Minimum Payments Due in 2022	338
Net Investment in Sales Type Leases, Future Minimum Payments-Gross	2,612	$ 2,111
Capital Leases, Future Minimum Payments Due in Five Years	$ 78

Accrued Liabilities (Details)

Accrued Liabilities (Details) - USD ($) $ in Thousands	Jun. 30, 2019	Dec. 31, 2018
Accrued Liabilities, Current [Abstract]
Payroll and related expenses	$ 5,946	$ 7,241
Accrued payables	2,214	2,115
Deferred Rent Credit, Current	1,997	0
Lease financing, current portion	961	956
Product warranty	355	376
Customer Refund Liability, Current	376	629
Sales and use tax payable	336	379
Other	717	1,189
Total accrued payroll and other current liabilities	$ 12,902	$ 12,885

Schedule of Product Liability (

Schedule of Product Liability (Details) - USD ($) $ in Thousands	3 Months Ended		6 Months Ended
	Jun. 30, 2019	Jun. 30, 2018	Jun. 30, 2019	Jun. 30, 2018	Dec. 31, 2017
Movement in Standard and Extended Product Warranty, Increase (Decrease) [Roll Forward]
Product warranty accrual, at the beginning of the period	$ 374	$ 303	$ 376
Warranty expenses accrued	92	129	169	$ 215
Product Warranty Accrual, Preexisting, Increase (Decrease)	(55)	(75)	(86)	(134)
Warranty settlements made	(56)	(51)	(104)	(128)
Product Warranty Accrual	$ 355	$ 306	$ 355	$ 306	$ 353

Balance Sheet Components Leases

Balance Sheet Components Leases (Details) - USD ($) $ in Millions	3 Months Ended		6 Months Ended
	Jun. 30, 2019	Jun. 30, 2018	Jun. 30, 2019	Jun. 30, 2018
Balance Sheet Components [Abstract]
Operating lease cost	$ 0.5	$ 0.7	$ 1.1	$ 1.3

Balance Sheet Components Supple

Balance Sheet Components Supplemental Balance Sheet Information Related to Leases (Details) - USD ($) $ in Thousands	Jun. 30, 2019	Dec. 31, 2018
Balance Sheet Components [Abstract]
Operating lease right of use asset	$ 5,409
Deferred Rent Credit, Current	1,997	$ 0
Other long-term liabilities	4,576
Total operating lease liabilities	$ 6,573

Balance Sheet Components Other

Balance Sheet Components Other Information Related to Leases (Details) $ in Thousands	3 Months Ended	6 Months Ended
	Jun. 30, 2019USD ($)	Jun. 30, 2019USD ($)
Balance Sheet Components [Abstract]
Cash paid for amounts included in the measurement of lease liabilities	$ 634	$ 1,264
Right-of-use assets obtained in exchange for lease obligations	$ 329	$ 1,018
Weighted average remaining lease term	2 years 10 months 2 days	2 years 10 months 2 days
Weighted average discount rate	8.00%	8.00%

Balance Sheet Components Maturi

Balance Sheet Components Maturities of Leases (Details) $ in Thousands	Jun. 30, 2019USD ($)
Balance Sheet Components [Abstract]
2019 (remaining nine months)	$ 1,126
2020	2,631
2021	2,585
2022	977
2023	35
Total maturities of lease liabilities	7,354
Less imputed interest	(781)
Total	$ 6,573

Convertible Senior Notes - Conv

Convertible Senior Notes - Convertible Notes and Options (Details)	Jun. 28, 2019USD ($)$ / shares	May 31, 2018USD ($)day$ / shares	Jun. 30, 2018USD ($)	Jun. 30, 2019USD ($)	Jun. 30, 2018USD ($)	Jun. 30, 2019USD ($)	Jun. 30, 2018USD ($)	Dec. 31, 2018USD ($)
Debt Instrument [Line Items]
Net carrying amount				$ 113,759,000		$ 113,759,000		$ 110,540,000
Total interest expense				2,170,000	$ 997,000
Convertible Debt | Convertible Senior Notes at 1.50%
Debt Instrument [Line Items]
Aggregate principal amount		$ 143,750,000		143,750,000		143,750,000		143,750,000
Stated interest rate		1.50%
Proceeds from issuance of convertible senior notes, net of issuance costs		$ 138,900,000
Unamortized debt discount				(26,953,000)		(26,953,000)		(29,846,000)
Unamortized issuance costs				(3,038,000)		(3,038,000)		(3,364,000)
Net carrying amount				113,759,000		113,759,000		110,540,000
Convertible Debt | Convertible Senior Notes At 1.50%, Option Portion
Debt Instrument [Line Items]
Aggregate principal amount		$ 18,750,000
Stated interest rate		1.50%
Conversion ratio		0.0310073
Convertible debt, conversion price (in dollars per share) | $ / shares		$ 32.25
Denominator in calculation of trading price		$ 1,000
Conditional cash repurchase, percent of principal		100.00%
Carrying amount of the equity component		$ 33,400,000		33,350,000		33,350,000		33,350,000
Debt discount effective interest rate			7.60%
Amortization of debt issuance costs			$ 4,900,000	166,000	74,000	326,000	$ 74,000
Amortization of debt issuance costs, liability component			3,800,000
Amortization of debt issuance costs, equity component			$ 1,100,000
Issuance costs				(1,136,000)		(1,136,000)		(1,136,000)
Net carrying amount				32,214,000		32,214,000		$ 32,214,000
Estimated fair value of the Notes				176,900,000		176,900,000
Denominator in closing price calculation				100		100
If-converted value, share price (in dollars per share) | $ / shares	$ 31.92
If-converted value of the Notes	$ 142,300,000
Contractual interest expense				539,000	264,000	1,078,000	264,000
Amortization of debt discount				1,471,000	659,000	2,893,000	659,000
Total interest expense				$ 2,176,000	$ 997,000	$ 4,297,000	$ 997,000
Convertible Debt | Convertible Senior Notes At 1.50%, Option Portion | Maximum
Debt Instrument [Line Items]
Convertible debt, threshold trading days | day		20
Convertible debt, threshold consecutive trading days | day		30
Percent of conversion price triggering conversion feature		130.00%
Convertible Debt | Convertible Senior Notes At 1.50%, Option Portion | Minimum
Debt Instrument [Line Items]
Convertible debt, threshold trading days | day		5
Convertible debt, threshold consecutive trading days | day		10
Percent of conversion price triggering conversion feature		98.00%

Convertible Senior Notes - Capp

Convertible Senior Notes - Capped Calls (Details) - USD ($) $ / shares in Units, $ in Thousands, shares in Millions	1 Months Ended	6 Months Ended
	May 31, 2018	Jun. 30, 2019	Dec. 31, 2018
Debt Instrument [Line Items]
Capped Calls, initial strike price (in dollars per share)	$ 32.25
Capped Calls, initial cap price (in dollars per share)	$ 38.94
Capped Calls, number of shares covered	4.5
Payment for purchase of capped calls	$ (8,900)	$ (8,907)
Issuance costs		(1,136)
Convertible Debt | Convertible Senior Notes At 1.50%, Option Portion
Debt Instrument [Line Items]
Carrying amount of the equity component	$ 33,400	33,350	$ 33,350
Carrying amount of equity component, net of capped calls		$ 23,307

Commitments Narrative (Details)

Commitments Narrative (Details) - USD ($) $ in Millions	Jun. 30, 2019	Dec. 31, 2018
Inventories
Unrecorded Unconditional Purchase Obligation [Line Items]
Unrecorded Unconditional Purchase Obligation	$ 11.5	$ 11.1

Stock Option Activity (Details)

Stock Option Activity (Details) - Stock Options $ / shares in Units, $ in Thousands	6 Months Ended	12 Months Ended
	Jun. 30, 2019USD ($)$ / sharesshares	Dec. 31, 2018USD ($)$ / sharesshares
Number of Options (in shares):
Beginning balance | shares	797,501
Options granted | shares	0
Options exercised | shares	(159,615)
Options canceled | shares	0
Ending balance | shares	637,886	797,501
Weighted Average Exercise Price (in dollars per share):
Beginning balance | $ / shares	$ 13.31
Options granted | $ / shares	0
Options exercised | $ / shares	13.10
Options canceled | $ / shares	0
Ending balance | $ / shares	$ 13.36	$ 13.31
Wtd avg remaining term, Outstanding	4 years 1 month 9 days	4 years 8 months 15 days
Aggregate intrinsic value, Outstanding | $	$ 11,838	$ 20,767

Summary of Equity B-S-M Assumpt

Summary of Equity B-S-M Assumptiuons (Details) - 2012 Employee Stock Purchase Plan - ESPP	3 Months Ended		6 Months Ended
	Jun. 30, 2019	Jun. 30, 2018	Jun. 30, 2019	Jun. 30, 2018
Equity B-S-M Fair Value Assumptions
Expected Term (in years)	6 months	6 months	6 months	6 months
Dividend yield	0.00%	0.00%	0.00%	0.00%
Minimum
Equity B-S-M Fair Value Assumptions
Volatility			33.00%	29.00%
Interest Rate			2.43%	1.39%
Maximum
Equity B-S-M Fair Value Assumptions
Expected Term (in years)
Volatility			45.20%	37.80%
Interest Rate			2.51%	2.09%

Summary of Restricted Stock Act

Summary of Restricted Stock Activity (Details) - Restricted Stock Units	6 Months Ended
	Jun. 30, 2019$ / sharesshares
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Stock Comp-other than options - Period for Recognition- Comp cost not yet rocognized	1 year 11 months 1 day
Number of Shares:
Beginning balance | shares	1,807,180
Granted | shares	728,625
Vested | shares	(804,810)
Forfeited | shares	(60,442)
Ending balance | shares	1,670,553
Weighted Average Grant Date Fair Value per Share (in dollars per share):
Beginning balance | $ / shares	$ 23.13
Granted | $ / shares	33.25
Vested | $ / shares	21.17
Forfeited | $ / shares	25.86
Ending balance | $ / shares	$ 28.39

Share-based Compensaton Allocat

Share-based Compensaton Allocated to Expense Captions (Details) - USD ($) $ in Thousands	3 Months Ended
	Jun. 30, 2019	Jun. 30, 2018
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Stock-based compensation expense	$ 6,109	$ 5,396
Cost of Sales
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Stock-based compensation expense	1,178	966
Research and Development Expense
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Stock-based compensation expense	1,034	755
Selling and Marketing Expense
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Stock-based compensation expense	1,758	1,655
General and Administrative Expense
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Stock-based compensation expense	$ 2,139	$ 2,020

Narrative (Details)

Narrative (Details) - USD ($) $ / shares in Units, $ in Millions	6 Months Ended
	Jun. 30, 2019	Jun. 30, 2018
ESPP plan details [Abstract]
Stock Issued During Period, Shares, Employee Stock Purchase Plans	61,691	78,563
Restricted stock units
Share-based Compensation Arrangement by Share-based Payment Award, Equity Instruments Other than Options, Additional Disclosures [Abstract]
Employee Service Share-based Compensation, Nonvested Awards, Compensation Not yet Recognized, Share-based Awards Other than Options	$ 39.8
Stock Comp-other than options - Period for Recognition- Comp cost not yet rocognized	1 year 11 months 1 day
2012 Stock Option Plan | Stock options and restricted stock units
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Number of Shares Available for Grant	2,017,431
2012 Employee Stock Purchase Plan | ESPP
ESPP plan details [Abstract]
Share-based Compensation Arrangement by Share-based Payment Award, Per Share Weighted Average Price of Shares Purchased	$ 29.32	$ 20.69
Common Stock, Capital Shares Reserved for Future Issuance	966,693

Segments Operating Segments (De

Segments Operating Segments (Details) $ in Thousands	3 Months Ended		6 Months Ended
	Jun. 30, 2019USD ($)	Jun. 30, 2018USD ($)	Jun. 30, 2019Segments
Segment Reporting Information [Line Items]
Number of reportable segments | Segments			2
Revenue
Total revenue	$ 44,759	$ 42,686
Cost of revenue
Total cost of revenue	17,743	17,035
Gross profit
Product	16,220	15,141
Service	10,796	10,510
Total gross profit	27,016	25,651
Calculation of pretax profit (loss) [Abstract]
Operating expenses	30,956	28,765
Interest income (expense), net and other	(997)	(995)
Loss before income taxes	(4,937)	(4,109)
Product
Revenue
Total revenue	23,132	21,824
Cost of revenue
Total cost of revenue	6,912	6,683
Service
Revenue
Total revenue	21,627	20,862
Cost of revenue
Total cost of revenue	$ 10,831	$ 10,352

Income Taxes (Details)

Income Taxes (Details) - USD ($) $ in Thousands	3 Months Ended		6 Months Ended
	Jun. 30, 2019	Jun. 30, 2018	Jun. 30, 2019
Income Tax Disclosure [Abstract]
Income Tax Expense (Benefit)	$ (80)	$ (555)	$ (100)