Vocera Communications (VCRA) 10-Q 5 Nov 18 2018 Q3 Quarterly report Financial data

Document and Entity Information

Document and Entity Information - shares	9 Months Ended
	Sep. 30, 2018	Nov. 02, 2018
Document and Entity Information [Abstract]
Entity Registrant Name	VOCERA COMMUNICATIONS, INC.
Entity Central Index Key	1,129,260
Document Type	10-Q
Document Period End Date	Sep. 30, 2018
Amendment Flag	false
Entity Emerging Growth Company	false
Entity Small Business	false
Document Fiscal Year Focus	2,018
Document Fiscal Period Focus	Q3
Current Fiscal Year End Date	--12-31
Entity Filer Category	Accelerated Filer
Entity Common Stock, Shares Outstanding		30,549,176

Condensed Consolidated Balance

Condensed Consolidated Balance Sheets - USD ($) $ in Thousands	Sep. 30, 2018	Dec. 31, 2017	[1]
Current assets
Cash and cash equivalents	$ 32,971	$ 28,726
Short-term investments	181,982	52,507
Accounts receivable, net of allowance	36,982	35,105
Other receivables	2,289	1,331
Inventories	3,678	2,815
Prepaid expenses and other current assets	4,513	3,957
Total current assets	262,415	124,441
Property and equipment, net	7,058	5,751
Intangible assets, net	10,234	13,567
Goodwill	49,246	49,246
Deferred commissions	9,475	10,301
Other long-term assets	1,718	1,667
Total assets	340,146	204,973
Current liabilities
Accounts payable	3,154	2,678
Accrued payroll and other current liabilities	13,458	14,689
Deferred revenue, current	41,410	40,734
Total current liabilities	58,022	58,101
Deferred revenue, long-term	12,898	14,417
Convertible senior notes, net	108,942	0
Other long-term liabilities	2,907	4,455
Total liabilities	182,769	76,973
Commitments and contingencies (Note 9)
Stockholders' equity
Preferred stock, $0.0003 par value - 5,000,000 shares authorized as of September 30, 2018 and December 31, 2017; zero shares issued and outstanding	0	0
Common stock, $0.0003 par value - 100,000,000 shares authorized as of September 30, 2018 and December 31, 2017; 30,456,187 and 29,412,116 shares issued and outstanding as of September 30, 2018 and December 31, 2017, respectively	9	9
Additional paid-in capital	288,936	250,854
Accumulated other comprehensive loss	(323)	(191)
Accumulated deficit	(131,245)	(122,672)
Total stockholders’ equity	157,377	128,000
Total liabilities and stockholders’ equity	$ 340,146	$ 204,973
[1]	See Note 1 for a summary of adjustments related to the adoption of the new revenue recognition standard.

Condensed Consolidated Balanc_2

Condensed Consolidated Balance Sheets Condensed Consolidated Balance Sheets (Paranthetical) - $ / shares	Sep. 30, 2018	Dec. 31, 2017
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	30,456,187	29,412,116
Common stock shares outstanding	30,456,187	29,412,116
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			9 Months Ended
		Sep. 30, 2018	Sep. 30, 2017		Sep. 30, 2018	Sep. 30, 2017
Revenue
Total revenue		$ 47,822	$ 45,585	[1]	$ 130,750	$ 121,869	[1]
Cost of revenue
Total cost of revenue		16,684	16,449	[1]	50,060	48,782
Gross profit		31,138	29,136	[1]	80,690	73,087
Operating expenses
Research and development		7,993	6,644	[1]	22,630	20,944	[1]
Sales and marketing		15,654	14,840	[1]	45,942	45,008	[1]
General and administrative		6,438	6,088	[1]	18,973	17,767	[1]
Total operating expenses		30,085	27,572	[1]	87,545	83,719	[1]
Income (loss) from operations		1,053	1,564	[1]	(6,855)	(10,632)	[1]
Interest income		1,110	177	[1]	1,855	410	[1]
Interest expense		(2,106)	0	[1]	(3,103)	0	[1]
Other income (expense), net		(158)	(41)	[1]	(965)	1	[1]
Loss before income taxes		(101)	1,700	[1]	(9,068)	(10,221)	[1]
Benefit from (provision for) income taxes		(148)	(309)	[1]	495	(1,050)	[1]
Net income (loss)		(249)	$ 1,391	[1]	(8,573)	$ (11,271)	[1]
Net income (loss) per share
Basic and Diluted	[1]		$ 0.05			$ (0.40)
Product
Revenue
Total revenue		27,341	$ 26,018	[1]	70,252	$ 67,062	[1]
Cost of revenue
Total cost of revenue		6,819	7,208	[1]	19,847	20,424
Service
Revenue
Total revenue		20,481	19,567	[1]	60,498	54,807	[1]
Cost of revenue
Total cost of revenue		$ 9,865	$ 9,241	[1]	$ 30,213	$ 28,358
[1]	See Note 1 for a summary of adjustments related to the adoption of the new revenue recognition standard.

Condensed Consolidated Statem_2

Condensed Consolidated Statements of Comprehensive Income - USD ($) $ in Thousands	3 Months Ended			9 Months Ended
	Sep. 30, 2018	Sep. 30, 2017	[1]	Sep. 30, 2018	Sep. 30, 2017	[1]
Statement of Comprehensive Income [Abstract]
Net loss	$ (249)	$ 1,391		$ (8,573)	$ (11,271)
Other comprehensive loss, net:
Change in unrealized gain (loss) on investments, net of tax	70	(15)		(132)	(24)
Comprehensive loss	$ (179)	$ 1,376		$ (8,705)	$ (11,295)
[1]	See Note 1 for a summary of adjustments related to the adoption of the new revenue recognition standard.

Condensed Consolidated Statem_3

Condensed Consolidated Statements of Cash Flows - USD ($) $ in Thousands		9 Months Ended
		Sep. 30, 2018	Sep. 30, 2017
Cash flows from operating activities
Net loss		$ (8,573)	$ (11,271)	[1]
Adjustments to reconcile net loss to net cash used in operating activities:
Depreciation and amortization		5,668	5,755	[1]
Inventory provision		0	179	[1]
Change in lease-related performance liabilities		298	(598)	[1]
Stock-based compensation expense		15,477	13,204	[1]
Amortization of debt discount and issuance costs		2,301	0	[1]
Other		24	28	[1]
Changes in operating assets and liabilities:
Accounts receivable		(1,873)	(11,310)	[1]
Other receivables		(958)	96	[1]
Inventories		(863)	1,262	[1]
Prepaid expenses and other assets		(605)	(1,539)	[1]
Deferred commissions		826	(781)	[1]
Accounts payable		435	(436)	[1]
Accrued payroll and other liabilities		(3,389)	925	[1]
Deferred revenue		(843)	(687)	[1]
Net cash used in operating activities		7,925	(5,173)	[1]
Cash flows from investing activities
Purchase of property and equipment		(3,624)	(2,420)	[1]
Purchase of short-term investments		(171,039)	(59,608)	[1]
Maturities of short-term investments		41,431	45,963	[1]
Net cash used in investing activities		(133,232)	(16,065)	[1]
Cash flows from financing activities
Cash from lease-related performance obligations		320	347	[1]
Proceeds from issuance of convertible senior notes, net of issuance costs		138,854	0	[1]
Payment for purchase of capped calls		(8,907)	0	[1]
Proceeds from issuance of common stock from the employee stock purchase plan		1,625	1,246	[1]
Proceeds from exercise of stock options		6,439	7,145	[1]
Tax withholdings paid on behalf of employees for net share settlement		(8,779)	(7,693)	[1]
Net cash provided by financing activities		129,552	1,045	[1]
Net decrease in cash and cash equivalents		4,245	(20,193)	[1]
Cash and cash equivalents at beginning of period	[1]	28,726	35,033
Cash and cash equivalents at end of period		32,971	14,840	[1]
Supplemental disclosure of non-cash investing and financing activities:
Property and equipment in accounts payable and accrued liabilities		$ 142	$ 40	[1]
[1]	See Note 1 for a summary of adjustments related to the adoption of the new revenue recognition standard.

The Company and Summary of Sign

The Company and Summary of Significant Accounting Policies	9 Months Ended
	Sep. 30, 2018
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, 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 patient experience, improve staff resiliency and increase operational efficiency. The Vocera communication and collaboration solution, which includes an intelligent enterprise software platform; a lightweight, wearable, voice-controlled communication badge; and smartphone applications, 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, 2017 . 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. Effective January 1, 2018, the Company adopted the requirements of Accounting Standards Update No. 2014-09, Revenue from Contracts with Customers, (ASC 606), as discussed in detail in Note 2. All amounts and disclosures set forth in this quarterly report on Form 10-Q have been updated to comply with ASC 606, as indicated by the "as adjusted" footnote. 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, 2018 or for any other interim period or any other future year. Except for the accounting policies for revenue recognition, deferred revenue and deferred commissions that were updated as a result of adopting ASC 606, 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, 2017. 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. Recently Adopted Accounting Pronouncement In May 2014, the Financial Accounting Standards Board (FASB) together with the International Accounting Standards Board issued converged guidance for revenue recognition that replaces most existing guidance, eliminates industry-specific guidance and provides a unified model for determining how and when revenue from contracts with customers should be recognized. Under the new guidance, an entity should recognize revenue to depict 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. The new guidance permits two methods of adoption: retrospectively to each prior reporting period presented (full retrospective method), or retrospectively with the cumulative effect of initially applying the guidance recognized at the date of initial application (modified retrospective method). The Company adopted the new guidance on January 1, 2018 using the full retrospective method, which requires the Company to present its historical financial information for fiscal years 2017 and 2016 as if the new revenue guidance had been applied to all prior periods. Refer to Note 2 for the details of impacts to previously reported results. In October 2016, the FASB issued amended guidance on the accounting for income taxes. The new guidance requires the recognition of the income tax consequences of an intercompany asset transfer, other than transfers of inventory, when the transfer occurs. The guidance is effective for reporting periods beginning after December 15, 2017, with early adoption permitted. The adoption of this standard did not have a material impact on the Company’s consolidated financial statements. In January 2017, the FASB issued new guidance which clarifies the definition of a business to assist companies with evaluating whether transactions should be accounted for as acquisitions of assets or businesses. The new guidance requires a company to evaluate if substantially all of the fair value of the gross assets acquired (or disposed of) is concentrated in a single identifiable asset or a group of similar identifiable assets; if so, the set of assets and activities is not a business. The guidance also requires a business to include at least one substantive process and narrows the definition of outputs by more closely aligning it with how outputs are described in the guidance for revenue from contracts with customers. The new guidance is effective for the Company in the first quarter of 2018. Early adoption is permitted. The guidance should be applied prospectively to any transactions occurring within the period of adoption. The adoption of this standard did not have a material impact on the Company’s consolidated financial statements. In May 2017, the FASB amended the scope of modification accounting for share-based payment arrangements. The guidance clarifies the type of changes to terms or conditions of share-based payment awards to which an entity would be required to apply modification accounting. Specifically, under this guidance, an entity would not apply modification accounting if the fair value, vesting conditions, and classification of the awards are the same immediately before and after the modification. The new standard is effective for the Company in the first quarter of 2018. Early adoption is permitted. The guidance will be applied prospectively to awards modified on or after the adoption date. The adoption of this standard did not have a material impact on the Company’s consolidated financial statements. Recent 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 will also require significant additional disclosures about the amount, timing and uncertainty of cash flows from leases. This new guidance will be 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 is currently evaluating the impact of the standard on its financial position or results of operations. 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. 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 will be 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 is not expected to have a material impact on the Company’s consolidated financial statements.

Revenue, deferred revenue, and

Revenue, deferred revenue, and deferred commissions	9 Months Ended
	Sep. 30, 2018
Revenue from Contract with Customer [Abstract]
Revenue, deferred revenue, and deferred commissions	Revenue, deferred revenue and deferred commissions Effective January 1, 2018, the Company adopted ASC 606 using the full retrospective method, which requires the Company to present its historical financial information for fiscal years 2017 and 2016 as if the new revenue guidance had been applied to all prior periods. The most significant impact of the standard relates to the timing of revenue recognition for software licenses sold with professional services where the Company did not have vendor specific objective evidence (“VSOE”) for professional services under current guidance. Under the new standard, the requirement to have VSOE for undelivered elements is eliminated and the Company will recognize revenue for software licenses upon transfer of control to its customers. Additionally, the new standard requires the capitalization and amortization of costs related to obtaining a contract, such as sales commissions, which were previously recorded as an expense to sales and marketing at the time they are incurred. 606 Adoption Impact to Previously Reported Results The Company adjusted its condensed consolidated financial statements from amounts previously reported due to the adoption of ASC 606. Select condensed consolidated balance sheet line items, which reflects the adoption of ASC 606, are as follows: Consolidated Balance Sheet As of December 31, 2017 (in thousands) As Reported Impact of Adoption As Adjusted Other receivables $ 1,170 $ 161 (1) $ 1,331 Deferred commissions $ — $ 10,301 (2) $ 10,301 Deferred revenue - current $ 47,276 $ (6,542 ) (1) $ 40,734 Deferred revenue - long-term 16,438 (2,021 ) (1) 14,417 Total deferred revenue $ 63,714 $ (8,563 ) $ 55,151 Stockholders' equity $ 108,975 $ 19,025 $ 128,000 (1) Impact of cumulative change in revenue. (2) Impact of cumulative change in commissions expense. Select unaudited condensed consolidated statement of operations line items, which reflects the adoption of ASC 606, are as follows: Consolidated Statement of Operations Three months ended September 30, 2017 Nine months ended September 30, 2017 (in thousands, except per share data) As Reported Impact of Adoption As Adjusted As Reported Impact of Adoption As Adjusted Revenue Product $ 23,249 $ 2,769 $ 26,018 $ 63,940 $ 3,122 $ 67,062 Service 19,051 516 19,567 53,105 1,702 54,807 Total Revenue $ 42,300 $ 3,285 $ 45,585 $ 117,045 $ 4,824 $ 121,869 Gross Profit $ 25,851 $ 3,285 $ 29,136 $ 68,263 $ 4,824 $ 73,087 Operating Expenses $ 28,563 $ (991 ) $ 27,572 $ 84,500 $ (781 ) $ 83,719 Loss from Operations $ (2,712 ) $ 4,276 $ 1,564 $ (16,237 ) $ 5,605 $ (10,632 ) Net Loss $ (2,885 ) $ 4,276 $ 1,391 $ (16,876 ) $ 5,605 $ (11,271 ) Basic net income (loss) per share $ (0.10 ) $ 0.15 $ 0.05 $ (0.59 ) $ 0.19 $ (0.40 ) Diluted net income (loss) per share $ (0.10 ) $ 0.15 $ 0.05 $ (0.59 ) $ 0.19 $ (0.40 ) The adoption impacted certain line items in the cash flows from operating activities as follows: Cash flows from operating activities: Nine months ended September 30, 2017 (in thousands) As Reported Impact of Adoption As Adjusted Net loss (16,876 ) 5,605 (11,271 ) Adjustments to reconcile net loss to net cash provided by operating activities: Deferred commissions $ — $ (781 ) $ (781 ) Deferred revenue $ 4,137 $ (4,824 ) $ (687 ) The core principle of ASC 606 is to recognize revenue to depict 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. This principle is achieved through applying the following five-step approach: • 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 multiple arrangements, 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 September 30, Nine months ended September 30, (in thousands) 2018 2017 2018 2017 Product revenue Device $ 17,031 $ 16,524 $ 44,728 $ 45,572 Software 10,310 9,494 25,524 21,490 Total product 27,341 26,018 70,252 67,062 Service revenue Maintenance and support 16,023 13,837 45,493 38,507 Professional services and training 4,458 5,730 15,005 16,300 Total service 20,481 19,567 60,498 54,807 Total revenue $ 47,822 $ 45,585 $ 130,750 $ 121,869 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 September 30, 2018 and December 31, 2017 is presented in the accompanying 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 nine months ended September 30, 2018 are as follows: (in thousands) June 30, 2018 Additions Commissions Recognized September 30, 2018 Deferred commissions $ 9,329 $ 1,283 $ (1,137 ) $ 9,475 (in thousands) December 31, 2017 *As Adjusted Additions Commissions Recognized September 30, 2018 Deferred commissions $ 10,301 $ 3,073 $ (3,899 ) $ 9,475 Of the $9.5 million total deferred commissions balance as of September 30, 2018 , the Company expects to recognize approximately 47.9% 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 nine months ended September 30, 2018 are as follows: (in thousands) June 30, 2018 Additions Revenue Recognized September 30, 2018 Deferred revenue $ 53,408 $ 18,142 $ (17,242 ) $ 54,308 (in thousands) December 31, 2017 *As Adjusted Additions Revenue Recognized September 30, 2018 Deferred revenue $ 55,151 $ 56,226 $ (57,069 ) $ 54,308 * See details above for the summary of adjustments to deferred commission and deferred revenue as a result of the adoption of ASC 606. Revenue recognized during the three and nine months ended September 30, 2018 from deferred revenue balances at the beginning of the period was $15.5 million and $36.9 million , respectively. Revenue recognized during the three and nine months ended September 30, 2017 from deferred revenue balances at the beginning of the period was $12.2 million and $27.5 million , respectively. The majority of the Company’s “contracted not recognized” performance obligations are not subject to cancellation terms. The Company’s “contracted 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 $117.2 million as of September 30, 2018 , of which the Company expects to recognize approximately 63% of the revenue over the next 12 months and the remainder thereafter.

Fair Value of Financial Instrum

Fair Value of Financial Instruments	9 Months Ended
	Sep. 30, 2018
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. For the nine months ended September 30, 2018 , 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 are 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 September 30, 2018 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 September 30, 2018 and December 31, 2017 , are summarized as follows (in thousands): September 30, 2018 December 31, 2017 Level 1 Level 2 Total Level 1 Level 2 Total Assets Money market funds $ 5,910 $ — $ 5,910 $ 3,232 $ — $ 3,232 Commercial paper — 34,308 34,308 — 1,201 1,201 U.S. government agency securities — 4,630 4,630 — 8,648 8,648 U.S. Treasury securities — 3,485 3,485 — 5,561 5,561 Corporate debt securities — 144,553 144,553 — 37,530 37,530 Total assets measured at fair value $ 5,910 $ 186,976 $ 192,886 $ 3,232 $ 52,940 $ 56,172

Cash, Cash Equivalents and Shor

Cash, Cash Equivalents and Short-term Investments	9 Months Ended
	Sep. 30, 2018
Cash and Cash Equivalents [Abstract]
Cash, Cash Equivalents, and Short-term Investments	Cash, Cash Equivalents and Short-Term Investments The following tables present current and prior-year-end balances for cash, cash equivalents and short-term investments (in thousands): As of September 30, 2018 Amortized Cost Unrealized Gains Unrealized Losses Fair value Cash and cash equivalents: Demand deposits and other cash $ 22,067 $ — $ — $ 22,067 Money market funds 5,910 — — 5,910 Commercial paper 4,995 — (1 ) 4,994 Total cash and cash equivalents 32,972 — (1 ) 32,971 Short-Term Investments: Commercial paper 29,328 — (14 ) 29,314 U.S. government agency securities 4,653 — (23 ) 4,630 U.S. Treasury securities 3,504 — (19 ) 3,485 Corporate debt securities 144,763 3 (213 ) 144,553 Total short-term investments 182,248 3 (269 ) 181,982 Total cash, cash equivalents and short-term investments $ 215,220 $ 3 $ (270 ) $ 214,953 As of December 31, 2017 Amortized Cost Unrealized Gains Unrealized Losses Fair value Cash and cash equivalents: Demand deposits and other cash $ 25,061 $ — $ — $ 25,061 Money market funds 3,232 — — 3,232 Corporate debt securities 433 — — 433 Total cash and cash equivalents 28,726 — — 28,726 Short-Term Investments: Commercial paper 1,202 — (1 ) 1,201 U.S. government agency securities 8,678 — (30 ) 8,648 U.S. Treasury securities 5,586 — (25 ) 5,561 Corporate debt securities 37,176 1 (80 ) 37,097 Total short-term investments 52,642 1 (136 ) 52,507 Total cash, cash equivalents and short-term investments $ 81,368 $ 1 $ (136 ) $ 81,233 The Company has determined that the unrealized losses on its short-term investments as of September 30, 2018 and December 31, 2017 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 equivalent 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 September 30, 2018 Cash and cash equivalents (1) $ 32,971 $ — $ 32,971 Short-term investments 117,463 64,519 181,982 Cash, cash equivalents and short-term investments $ 150,434 $ 64,519 $ 214,953 Balances as of December 31, 2017 Cash and cash equivalents (1) $ 28,726 $ — $ 28,726 Short-term investments 34,750 17,757 52,507 Cash, cash equivalents and short-term investments $ 63,476 $ 17,757 $ 81,233 (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	9 Months Ended
	Sep. 30, 2018
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 September 30, Nine months ended September 30, 2018 2017 2018 2017 * As Adjusted * As Adjusted Numerator: Net income (loss) $ (249 ) $ 1,391 $ (8,573 ) $ (11,271 ) Denominator: Weighted-average shares used to compute net income (loss) per common share - basic 30,230 29,130 29,861 28,439 Effect of potentially dilutive securities: Employee stock options and restricted stock units — 1,343 — — Weighted average shares used to compute diluted income (loss) per common share 30,230 30,473 29,861 28,439 Net income (loss) per share Basic $ (0.01 ) $ 0.05 $ (0.29 ) $ (0.40 ) Diluted $ (0.01 ) $ 0.05 $ (0.29 ) $ (0.40 ) The following securities were not included in the calculation of diluted shares outstanding as the effect would have been anti-dilutive: Three months ended September 30, Nine months ended September 30, (in thousands) 2018 2017 2018 2017 Options to purchase common stock, including ESPP 962 2 1,176 1,735 Restricted stock units 1,911 — 1,964 2,216

Goodwill and Intangible Assets

Goodwill and Intangible Assets	9 Months Ended
	Sep. 30, 2018
Goodwill and Intangible Assets Disclosure [Abstract]
Goodwill and Intangible Assets	Goodwill and Intangible Assets Goodwill As of September 30, 2018 and December 31, 2017 , 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 September 30, 2018 , 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: September 30, 2018 December 31, 2017 (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 $ 7,124 $ 2,926 $ 10,050 $ 5,302 $ 4,748 Customer relationships 7 to 9 10,920 4,351 6,569 10,920 3,469 7,451 Backlog 3 1,400 1,023 377 1,400 650 750 Non-compete agreements 2 to 4 460 460 — 460 455 5 Trademarks 3 to 7 1,110 748 362 1,110 497 613 Intangible assets, net book value $ 23,940 $ 13,706 $ 10,234 $ 23,940 $ 10,373 $ 13,567 Amortization expense was $1.0 million and $1.2 million for the three months ended September 30, 2018 and 2017 , respectively. Amortization expense was $3.3 million and $3.5 million for the nine months ended September 30, 2018 and 2017 , 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 September 30, 2018 was as follows: (in thousands) Future amortization 2018 (remaining three months) $ 1,001 2019 3,880 2020 1,251 2021 1,127 2022 1,050 2023 1,050 Thereafter 875 Future amortization expense $ 10,234

Balance Sheet Components

Balance Sheet Components	9 Months Ended
	Sep. 30, 2018
Balance Sheet Components [Abstract]
Balance Sheet Components	Balance Sheet Components Inventories (in thousands) September 30, December 31, Raw materials $ 274 $ 4 Finished goods 3,404 2,811 Total inventories $ 3,678 $ 2,815 Property and equipment, net (in thousands) September 30, December 31, Computer equipment and software $ 9,965 $ 8,832 Furniture, fixtures and equipment 2,261 1,764 Leasehold improvements 5,819 4,794 Manufacturing tools and equipment 1,990 2,624 Construction in process 371 157 Property and equipment, at cost 20,406 18,171 Less: Accumulated depreciation (13,348 ) (12,420 ) Property and equipment, net $ 7,058 $ 5,751 Depreciation and amortization expense was $0.9 million and $0.8 million for the three months ended September 30, 2018 and 2017 , respectively. Depreciation and amortization expense was $2.3 million and $2.2 million for the nine months ended September 30, 2018 and 2017 , respectively. Net investment in sales-type leases The Company has sales-type leases with terms of 2 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) September 30, December 31, Minimum payments to be received on sales-type leases $ 2,246 $ 2,758 Less: Unearned interest income and executory costs (1,345 ) (1,469 ) Net investment in sales-type leases 901 1,289 Less: Current portion (525 ) (916 ) Non-current net investment in sales-type leases $ 376 $ 373 There were no allowances for doubtful accounts on these leases as of September 30, 2018 and December 31, 2017 . 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 September 30, 2018 were as follows: (in thousands) Future lease payments 2018 $ 395 2019 1,038 2020 649 2021 139 2022 25 Total $ 2,246 Accrued payroll and other current liabilities (in thousands) September 30, December 31, Payroll and related expenses $ 6,921 $ 9,569 Accrued payables 2,487 1,801 Deferred rent, current portion 301 271 Lease financing, current portion 915 832 Product warranty 351 353 Customer prepayments 650 1,084 Sales and use tax payable 505 505 Other 1,328 274 Total accrued payroll and other current liabilities $ 13,458 $ 14,689 The changes in the Company’s product warranty reserve are as follows: Three months ended September 30, Nine months ended September 30, (in thousands) 2018 2017 2018 2017 Warranty balance at the beginning of the period $ 306 $ 315 $ 353 $ 596 Warranty expense accrued for shipments during the period 131 118 345 376 Changes in estimate related to pre-existing warranties (45 ) (49 ) (179 ) (426 ) Warranty settlements made (41 ) (73 ) (168 ) (235 ) Total product warranty $ 351 $ 311 $ 351 $ 311

Convertible Senior Notes

Convertible Senior Notes	9 Months Ended
	Sep. 30, 2018
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 three and nine months ended September 30, 2018 , the conditions allowing holders of the Notes to convert have not been met. The Notes are therefore not convertible during the three and nine months ended September 30, 2018 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) September 30, Liability: Principal $ 143,750 Unamortized debt discount (31,282 ) Unamortized issuance costs $ (3,526 ) Net carrying amount $ 108,942 Stockholders’ equity: Debt discount for conversion option $ 33,350 Issuance costs $ (1,136 ) Net carrying amount $ 32,214 The total estimated fair value of the Notes as of September 30, 2018 was approximately $178.6 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 $36.58 on September 28, 2018, the if-converted value of the Notes of $163.1 million was greater than their principal amount. Interest expense related to the Notes is as follows: Three months ended September 30, Nine months ended September 30, (in thousands) 2018 2018 Contractual interest expense $ 539 $ 803 Amortization of debt discount $ 1,408 $ 2,067 Amortization of issuance costs $ 159 $ 233 Total interest expense $ 2,106 $ 3,103 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) September 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 report 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	9 Months Ended
	Sep. 30, 2018
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 September 30, 2018 and December 31, 2017 , approximately $10.9 million and $4.4 million , respectively, of such inventory was purchased and held by the third-party manufacturers which was subject to these purchase guarantees. Leases The Company leases office space for its headquarters and subsidiaries under non-cancelable operating leases, which will expire between December 2018 and February 2023. The Company recognizes rent expense on a straight-line basis over the lease period, and has accrued for rent expense incurred but not paid. Facilities rent expense was $0.7 million and $0.6 million for the three months ended September 30, 2018 and 2017 , respectively. Facilities rent expense was $2.0 million and $1.9 million for the nine months ended September 30, 2018 and 2017 , respectively. Future minimum lease payments at September 30, 2018 under non-cancelable operating leases are as follows: (in thousands) Operating leases 2018 (remaining three months) $ 582 2019 2,222 2020 2,078 2021 1,837 2022 612 2023 35 Total minimum lease payments $ 7,366 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	9 Months Ended
	Sep. 30, 2018
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 nine months ended September 30, 2018 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, 2017 1,332,063 $ 13.48 5.36 $ 22,298 Options granted — — Options exercised (435,326 ) 14.79 Options canceled (2,774 ) 4.97 Outstanding at September 30, 2018 893,963 $ 12.88 4.88 $ 21,191 At September 30, 2018 , there was $0.1 million of unrecognized compensation cost related to options which is expected to be recognized over a weighted-average period of 0.45 years . As of September 30, 2018 , there were 2,375,322 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 nine months ended September 30, 2018 , employees purchased 78,563 shares of common stock at an average price of $20.69 . During the nine months ended September 30, 2017 , employees purchased 89,813 shares of common stock at an average purchase price of $13.87 . As of September 30, 2018 , there were 800,166 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 September 30, Nine months ended September 30, 2018 2017 2018 2017 Expected term (in years) 0.50 0.50 0.50 0.50 Volatility 37.8% 30.0% 29.0% - 37.8% 30.0% - 32.0% Risk-free interest rate 2.09% 1.02% 1.39% - 2.09% 0.61% - 1.02% Dividend yield 0% 0% 0% 0% Restricted Stock Units A summary of RSU activity for the nine months ended September 30, 2018 is presented below: Restricted Stock Units Number of shares Weighted Average Grant Date Fair Value per Share Outstanding at December 31, 2017 2,045,589 $ 18.84 Granted 837,571 25.94 Vested (865,397 ) 17.09 Forfeited (107,039 ) 21.10 Outstanding at September 30, 2018 1,910,724 $ 22.61 At September 30, 2018 , there was $33.4 million of unrecognized compensation cost related to RSUs, which is expected to be recognized over a weighted-average period of 1.73 years . Allocation of Stock-Based Compensation Expense The following table presents the allocation of stock-based compensation expense: Three months ended September 30, Nine months ended September 30, (in thousands) 2018 2017 2018 2017 Cost of revenue $ 923 $ 749 $ 2,636 $ 2,117 Research and development 802 507 2,164 1,542 Sales and marketing 1,755 1,653 4,906 4,697 General and administrative 2,014 1,809 5,771 4,848 Total stock-based compensation $ 5,494 $ 4,718 $ 15,477 $ 13,204

Segments

Segments	9 Months Ended
	Sep. 30, 2018
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’s and its wholly-owned subsidiaries’ results of operations. The following table presents a summary of the operating segments: Three months ended September 30, Nine months ended September 30, 2018 2017 2018 2017 (in thousands) * As Adjusted * As Adjusted Revenue Product $ 27,341 $ 26,018 $ 70,252 $ 67,062 Service 20,481 19,567 60,498 54,807 Total revenue 47,822 45,585 130,750 121,869 Cost of revenue Product 6,819 7,208 19,847 20,424 Service 9,865 9,241 30,213 28,358 Total cost of revenue 16,684 16,449 50,060 48,782 Gross profit Product 20,522 18,810 50,405 46,638 Service 10,616 10,326 30,285 26,449 Total gross profit 31,138 29,136 80,690 73,087 Operating expenses 30,085 27,572 87,545 83,719 Interest income (expense), net and other (1,154 ) 136 (2,213 ) 411 Loss before income taxes $ (101 ) $ 1,700 $ (9,068 ) $ (10,221 )

Income Taxes

Income Taxes	9 Months Ended
	Sep. 30, 2018
Income Tax Disclosure [Abstract]
Income Taxes	Income Taxes The Company recorded a $0.5 million benefit from income taxes and $1.1 million provision for income taxes for the nine months ended September 30, 2018 and 2017 , respectively. The benefit recorded for the nine months ended September 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. The provision for the nine months ended September 30, 2017 was primarily due to the accretion of the deferred tax liability associated with indefinite lived intangibles, taxes on international operations and state income taxes as well as the accretion of a deferred tax liability associated with goodwill related to acquisitions. As of September 30, 2018 , 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 September 30, 2018 , 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, 2017 .

The Company and Summary of Si_2

The Company and Summary of Significant Accounting Policies (Policies)	9 Months Ended
	Sep. 30, 2018
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, 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 patient experience, improve staff resiliency and increase operational efficiency. The Vocera communication and collaboration solution, which includes an intelligent enterprise software platform; a lightweight, wearable, voice-controlled communication badge; and smartphone applications, 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, 2017 . 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. Effective January 1, 2018, the Company adopted the requirements of Accounting Standards Update No. 2014-09, Revenue from Contracts with Customers, (ASC 606), as discussed in detail in Note 2. All amounts and disclosures set forth in this quarterly report on Form 10-Q have been updated to comply with ASC 606, as indicated by the "as adjusted" footnote. 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, 2018 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	Recent 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 will also require significant additional disclosures about the amount, timing and uncertainty of cash flows from leases. This new guidance will be 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 is currently evaluating the impact of the standard on its financial position or results of operations. 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. 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 will be 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 is not expected to have a material impact on the Company’s 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. For the nine months ended September 30, 2018 , 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 are 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 September 30, 2018 and December 31, 2017 , 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 September 30, 2018 , there were no changes in circumstances indicating that the carrying values of goodwill or acquired intangibles may not be recoverable.
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 September 30, 2018 and December 31, 2017 , approximately $10.9 million and $4.4 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 leases office space for its headquarters and subsidiaries under non-cancelable operating leases, which will expire between December 2018 and February 2023. The Company recognizes rent expense on a straight-line basis over the lease period, and has accrued for rent expense incurred but not paid. Facilities rent expense was $0.7 million and $0.6 million for the three months ended September 30, 2018 and 2017 , respectively.
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’s and its wholly-owned subsidiaries’ results of operations.
Revenue Recognition	The core principle of ASC 606 is to recognize revenue to depict 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. This principle is achieved through applying the following five-step approach: • 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 multiple arrangements, 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 September 30, Nine months ended September 30, (in thousands) 2018 2017 2018 2017 Product revenue Device $ 17,031 $ 16,524 $ 44,728 $ 45,572 Software 10,310 9,494 25,524 21,490 Total product 27,341 26,018 70,252 67,062 Service revenue Maintenance and support 16,023 13,837 45,493 38,507 Professional services and training 4,458 5,730 15,005 16,300 Total service 20,481 19,567 60,498 54,807 Total revenue $ 47,822 $ 45,585 $ 130,750 $ 121,869 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 September 30, 2018 and December 31, 2017 is presented in the accompanying 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 nine months ended September 30, 2018 are as follows: (in thousands) June 30, 2018 Additions Commissions Recognized September 30, 2018 Deferred commissions $ 9,329 $ 1,283 $ (1,137 ) $ 9,475 (in thousands) December 31, 2017 *As Adjusted Additions Commissions Recognized September 30, 2018 Deferred commissions $ 10,301 $ 3,073 $ (3,899 ) $ 9,475 Of the $9.5 million total deferred commissions balance as of September 30, 2018 , the Company expects to recognize approximately 47.9% 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 nine months ended September 30, 2018 are as follows: (in thousands) June 30, 2018 Additions Revenue Recognized September 30, 2018 Deferred revenue $ 53,408 $ 18,142 $ (17,242 ) $ 54,308 (in thousands) December 31, 2017 *As Adjusted Additions Revenue Recognized September 30, 2018 Deferred revenue $ 55,151 $ 56,226 $ (57,069 ) $ 54,308 * See details above for the summary of adjustments to deferred commission and deferred revenue as a result of the adoption of ASC 606. Revenue recognized during the three and nine months ended September 30, 2018 from deferred revenue balances at the beginning of the period was $15.5 million and $36.9 million , respectively. Revenue recognized during the three and nine months ended September 30, 2017 from deferred revenue balances at the beginning of the period was $12.2 million and $27.5 million , respectively. The majority of the Company’s “contracted not recognized” performance obligations are not subject to cancellation terms. The Company’s “contracted 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 $117.2 million as of September 30, 2018 , of which the Company expects to recognize approximately 63% of the revenue over the next 12 months and the remainder thereafter.

Revenue, deferred revenue, an_2

Revenue, deferred revenue, and deferred commissions (Tables)	9 Months Ended
	Sep. 30, 2018
Revenue from Contract with Customer [Abstract]
Schedule of New Accounting Pronouncements and Changes in Accounting Principles	Select condensed consolidated balance sheet line items, which reflects the adoption of ASC 606, are as follows: Consolidated Balance Sheet As of December 31, 2017 (in thousands) As Reported Impact of Adoption As Adjusted Other receivables $ 1,170 $ 161 (1) $ 1,331 Deferred commissions $ — $ 10,301 (2) $ 10,301 Deferred revenue - current $ 47,276 $ (6,542 ) (1) $ 40,734 Deferred revenue - long-term 16,438 (2,021 ) (1) 14,417 Total deferred revenue $ 63,714 $ (8,563 ) $ 55,151 Stockholders' equity $ 108,975 $ 19,025 $ 128,000 (1) Impact of cumulative change in revenue. (2) Impact of cumulative change in commissions expense. Select unaudited condensed consolidated statement of operations line items, which reflects the adoption of ASC 606, are as follows: Consolidated Statement of Operations Three months ended September 30, 2017 Nine months ended September 30, 2017 (in thousands, except per share data) As Reported Impact of Adoption As Adjusted As Reported Impact of Adoption As Adjusted Revenue Product $ 23,249 $ 2,769 $ 26,018 $ 63,940 $ 3,122 $ 67,062 Service 19,051 516 19,567 53,105 1,702 54,807 Total Revenue $ 42,300 $ 3,285 $ 45,585 $ 117,045 $ 4,824 $ 121,869 Gross Profit $ 25,851 $ 3,285 $ 29,136 $ 68,263 $ 4,824 $ 73,087 Operating Expenses $ 28,563 $ (991 ) $ 27,572 $ 84,500 $ (781 ) $ 83,719 Loss from Operations $ (2,712 ) $ 4,276 $ 1,564 $ (16,237 ) $ 5,605 $ (10,632 ) Net Loss $ (2,885 ) $ 4,276 $ 1,391 $ (16,876 ) $ 5,605 $ (11,271 ) Basic net income (loss) per share $ (0.10 ) $ 0.15 $ 0.05 $ (0.59 ) $ 0.19 $ (0.40 ) Diluted net income (loss) per share $ (0.10 ) $ 0.15 $ 0.05 $ (0.59 ) $ 0.19 $ (0.40 ) The adoption impacted certain line items in the cash flows from operating activities as follows: Cash flows from operating activities: Nine months ended September 30, 2017 (in thousands) As Reported Impact of Adoption As Adjusted Net loss (16,876 ) 5,605 (11,271 ) Adjustments to reconcile net loss to net cash provided by operating activities: Deferred commissions $ — $ (781 ) $ (781 ) Deferred revenue $ 4,137 $ (4,824 ) $ (687 )
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 September 30, Nine months ended September 30, (in thousands) 2018 2017 2018 2017 Product revenue Device $ 17,031 $ 16,524 $ 44,728 $ 45,572 Software 10,310 9,494 25,524 21,490 Total product 27,341 26,018 70,252 67,062 Service revenue Maintenance and support 16,023 13,837 45,493 38,507 Professional services and training 4,458 5,730 15,005 16,300 Total service 20,481 19,567 60,498 54,807 Total revenue $ 47,822 $ 45,585 $ 130,750 $ 121,869
Contract with Customer, Asset and Liability	hanges in the balance of total deferred commissions (contract asset) during the three and nine months ended September 30, 2018 are as follows: (in thousands) June 30, 2018 Additions Commissions Recognized September 30, 2018 Deferred commissions $ 9,329 $ 1,283 $ (1,137 ) $ 9,475 hanges in the balance of total deferred revenue (contract liability) during the three and nine months ended September 30, 2018 are as follows: (in thousands) June 30, 2018 Additions Revenue Recognized September 30, 2018 Deferred revenue $ 53,408 $ 18,142 $ (17,242 ) $ 54,308

Fair Value of Financial Insturm

Fair Value of Financial Insturments (Tables)	9 Months Ended
	Sep. 30, 2018
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 September 30, 2018 and December 31, 2017 , are summarized as follows (in thousands): September 30, 2018 December 31, 2017 Level 1 Level 2 Total Level 1 Level 2 Total Assets Money market funds $ 5,910 $ — $ 5,910 $ 3,232 $ — $ 3,232 Commercial paper — 34,308 34,308 — 1,201 1,201 U.S. government agency securities — 4,630 4,630 — 8,648 8,648 U.S. Treasury securities — 3,485 3,485 — 5,561 5,561 Corporate debt securities — 144,553 144,553 — 37,530 37,530 Total assets measured at fair value $ 5,910 $ 186,976 $ 192,886 $ 3,232 $ 52,940 $ 56,172

Cash, Cash Equivalents and Sh_2

Cash, Cash Equivalents and Short-term Investments (Tables)	9 Months Ended
	Sep. 30, 2018
Cash and Cash Equivalents [Abstract]
Schedule of Cash, Cash Equivalents and Available-For-Sale Investments	The following tables present current and prior-year-end balances for cash, cash equivalents and short-term investments (in thousands): As of September 30, 2018 Amortized Cost Unrealized Gains Unrealized Losses Fair value Cash and cash equivalents: Demand deposits and other cash $ 22,067 $ — $ — $ 22,067 Money market funds 5,910 — — 5,910 Commercial paper 4,995 — (1 ) 4,994 Total cash and cash equivalents 32,972 — (1 ) 32,971 Short-Term Investments: Commercial paper 29,328 — (14 ) 29,314 U.S. government agency securities 4,653 — (23 ) 4,630 U.S. Treasury securities 3,504 — (19 ) 3,485 Corporate debt securities 144,763 3 (213 ) 144,553 Total short-term investments 182,248 3 (269 ) 181,982 Total cash, cash equivalents and short-term investments $ 215,220 $ 3 $ (270 ) $ 214,953 As of December 31, 2017 Amortized Cost Unrealized Gains Unrealized Losses Fair value Cash and cash equivalents: Demand deposits and other cash $ 25,061 $ — $ — $ 25,061 Money market funds 3,232 — — 3,232 Corporate debt securities 433 — — 433 Total cash and cash equivalents 28,726 — — 28,726 Short-Term Investments: Commercial paper 1,202 — (1 ) 1,201 U.S. government agency securities 8,678 — (30 ) 8,648 U.S. Treasury securities 5,586 — (25 ) 5,561 Corporate debt securities 37,176 1 (80 ) 37,097 Total short-term investments 52,642 1 (136 ) 52,507 Total cash, cash equivalents and short-term investments $ 81,368 $ 1 $ (136 ) $ 81,233
Investments Classified by Contractual Maturity Date	Classification of the cash, cash equivalent 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 September 30, 2018 Cash and cash equivalents (1) $ 32,971 $ — $ 32,971 Short-term investments 117,463 64,519 181,982 Cash, cash equivalents and short-term investments $ 150,434 $ 64,519 $ 214,953 Balances as of December 31, 2017 Cash and cash equivalents (1) $ 28,726 $ — $ 28,726 Short-term investments 34,750 17,757 52,507 Cash, cash equivalents and short-term investments $ 63,476 $ 17,757 $ 81,233 (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)	9 Months Ended
	Sep. 30, 2018
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 September 30, Nine months ended September 30, 2018 2017 2018 2017 * As Adjusted * As Adjusted Numerator: Net income (loss) $ (249 ) $ 1,391 $ (8,573 ) $ (11,271 ) Denominator: Weighted-average shares used to compute net income (loss) per common share - basic 30,230 29,130 29,861 28,439 Effect of potentially dilutive securities: Employee stock options and restricted stock units — 1,343 — — Weighted average shares used to compute diluted income (loss) per common share 30,230 30,473 29,861 28,439 Net income (loss) per share Basic $ (0.01 ) $ 0.05 $ (0.29 ) $ (0.40 ) Diluted $ (0.01 ) $ 0.05 $ (0.29 ) $ (0.40 )
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 September 30, Nine months ended September 30, (in thousands) 2018 2017 2018 2017 Options to purchase common stock, including ESPP 962 2 1,176 1,735 Restricted stock units 1,911 — 1,964 2,216

Goodwill and Intangible Assets

Goodwill and Intangible Assets (Tables)	9 Months Ended
	Sep. 30, 2018
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: September 30, 2018 December 31, 2017 (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 $ 7,124 $ 2,926 $ 10,050 $ 5,302 $ 4,748 Customer relationships 7 to 9 10,920 4,351 6,569 10,920 3,469 7,451 Backlog 3 1,400 1,023 377 1,400 650 750 Non-compete agreements 2 to 4 460 460 — 460 455 5 Trademarks 3 to 7 1,110 748 362 1,110 497 613 Intangible assets, net book value $ 23,940 $ 13,706 $ 10,234 $ 23,940 $ 10,373 $ 13,567
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 September 30, 2018 was as follows: (in thousands) Future amortization 2018 (remaining three months) $ 1,001 2019 3,880 2020 1,251 2021 1,127 2022 1,050 2023 1,050 Thereafter 875 Future amortization expense $ 10,234

Balance Sheet Components (Table

Balance Sheet Components (Tables)	9 Months Ended
	Sep. 30, 2018
Balance Sheet Components [Abstract]
Inventories	Inventories (in thousands) September 30, December 31, Raw materials $ 274 $ 4 Finished goods 3,404 2,811 Total inventories $ 3,678 $ 2,815
Property and Equipment	Property and equipment, net (in thousands) September 30, December 31, Computer equipment and software $ 9,965 $ 8,832 Furniture, fixtures and equipment 2,261 1,764 Leasehold improvements 5,819 4,794 Manufacturing tools and equipment 1,990 2,624 Construction in process 371 157 Property and equipment, at cost 20,406 18,171 Less: Accumulated depreciation (13,348 ) (12,420 ) Property and equipment, net $ 7,058 $ 5,751 Depreciation and amortization expense was $0.9 million and $0.8 million for the three months ended September 30, 2018 and 2017 , respectively. Depreciation and amortization expense was $2.3 million and $2.2 million for the nine months ended September 30, 2018 and 2017 , respectively.
Schedule of Components of Leveraged Lease Investments	Net investment in sales-type leases The Company has sales-type leases with terms of 2 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) September 30, December 31, Minimum payments to be received on sales-type leases $ 2,246 $ 2,758 Less: Unearned interest income and executory costs (1,345 ) (1,469 ) Net investment in sales-type leases 901 1,289 Less: Current portion (525 ) (916 ) Non-current net investment in sales-type leases $ 376 $ 373 There were no allowances for doubtful accounts on these leases as of September 30, 2018 and December 31, 2017 . 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 September 30, 2018 were as follows: (in thousands) Future lease payments 2018 $ 395 2019 1,038 2020 649 2021 139 2022 25 Total $ 2,246
Accrued Liabilities	Accrued payroll and other current liabilities (in thousands) September 30, December 31, Payroll and related expenses $ 6,921 $ 9,569 Accrued payables 2,487 1,801 Deferred rent, current portion 301 271 Lease financing, current portion 915 832 Product warranty 351 353 Customer prepayments 650 1,084 Sales and use tax payable 505 505 Other 1,328 274 Total accrued payroll and other current liabilities $ 13,458 $ 14,689
Schedule of Product Warranty Liability	The changes in the Company’s product warranty reserve are as follows: Three months ended September 30, Nine months ended September 30, (in thousands) 2018 2017 2018 2017 Warranty balance at the beginning of the period $ 306 $ 315 $ 353 $ 596 Warranty expense accrued for shipments during the period 131 118 345 376 Changes in estimate related to pre-existing warranties (45 ) (49 ) (179 ) (426 ) Warranty settlements made (41 ) (73 ) (168 ) (235 ) Total product warranty $ 351 $ 311 $ 351 $ 311

Convertible Senior Notes (Table

Convertible Senior Notes (Tables)	9 Months Ended
	Sep. 30, 2018
Debt Disclosure [Abstract]
Schedule of Notes	The Notes consist of the following: (in thousands) September 30, Liability: Principal $ 143,750 Unamortized debt discount (31,282 ) Unamortized issuance costs $ (3,526 ) Net carrying amount $ 108,942 Stockholders’ equity: Debt discount for conversion option $ 33,350 Issuance costs $ (1,136 ) Net carrying amount $ 32,214
Schedule of Interest Expense Related to the Notes	Interest expense related to the Notes is as follows: Three months ended September 30, Nine months ended September 30, (in thousands) 2018 2018 Contractual interest expense $ 539 $ 803 Amortization of debt discount $ 1,408 $ 2,067 Amortization of issuance costs $ 159 $ 233 Total interest expense $ 2,106 $ 3,103
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) September 30, Conversion option $ 33,350 Purchase of capped calls $ (8,907 ) Issuance costs $ (1,136 ) Total $ 23,307

Commitments and Contingencies (

Commitments and Contingencies (Tables)	9 Months Ended
	Sep. 30, 2018
Commitments and Contingencies Disclosure [Abstract]
Schedule of Future Minimum Rental Payments for Operating Leases	Future minimum lease payments at September 30, 2018 under non-cancelable operating leases are as follows: (in thousands) Operating leases 2018 (remaining three months) $ 582 2019 2,222 2020 2,078 2021 1,837 2022 612 2023 35 Total minimum lease payments $ 7,366

Stock-based Compensation and _2

Stock-based Compensation and Awards (Tables)	9 Months Ended
	Sep. 30, 2018
Disclosure of Compensation Related Costs, Share-based Payments [Abstract]
Rollforward of stock option activity	A summary of the stock option activity for the nine months ended September 30, 2018 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, 2017 1,332,063 $ 13.48 5.36 $ 22,298 Options granted — — Options exercised (435,326 ) 14.79 Options canceled (2,774 ) 4.97 Outstanding at September 30, 2018 893,963 $ 12.88 4.88 $ 21,191
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 September 30, Nine months ended September 30, 2018 2017 2018 2017 Expected term (in years) 0.50 0.50 0.50 0.50 Volatility 37.8% 30.0% 29.0% - 37.8% 30.0% - 32.0% Risk-free interest rate 2.09% 1.02% 1.39% - 2.09% 0.61% - 1.02% Dividend yield 0% 0% 0% 0%
Rollforward of RSA and RSU activty	A summary of RSU activity for the nine months ended September 30, 2018 is presented below: Restricted Stock Units Number of shares Weighted Average Grant Date Fair Value per Share Outstanding at December 31, 2017 2,045,589 $ 18.84 Granted 837,571 25.94 Vested (865,397 ) 17.09 Forfeited (107,039 ) 21.10 Outstanding at September 30, 2018 1,910,724 $ 22.61
Allocation of Recognized Period Costs	The following table presents the allocation of stock-based compensation expense: Three months ended September 30, Nine months ended September 30, (in thousands) 2018 2017 2018 2017 Cost of revenue $ 923 $ 749 $ 2,636 $ 2,117 Research and development 802 507 2,164 1,542 Sales and marketing 1,755 1,653 4,906 4,697 General and administrative 2,014 1,809 5,771 4,848 Total stock-based compensation $ 5,494 $ 4,718 $ 15,477 $ 13,204

Segments Segments (Tables)

Segments Segments (Tables)	9 Months Ended
	Sep. 30, 2018
Segment Reporting [Abstract]
Segments	The following table presents a summary of the operating segments: Three months ended September 30, Nine months ended September 30, 2018 2017 2018 2017 (in thousands) * As Adjusted * As Adjusted Revenue Product $ 27,341 $ 26,018 $ 70,252 $ 67,062 Service 20,481 19,567 60,498 54,807 Total revenue 47,822 45,585 130,750 121,869 Cost of revenue Product 6,819 7,208 19,847 20,424 Service 9,865 9,241 30,213 28,358 Total cost of revenue 16,684 16,449 50,060 48,782 Gross profit Product 20,522 18,810 50,405 46,638 Service 10,616 10,326 30,285 26,449 Total gross profit 31,138 29,136 80,690 73,087 Operating expenses 30,085 27,572 87,545 83,719 Interest income (expense), net and other (1,154 ) 136 (2,213 ) 411 Loss before income taxes $ (101 ) $ 1,700 $ (9,068 ) $ (10,221 )

The Company and Summary of Si_3

The Company and Summary of Significant Accounting Policies Narrative (Details) - USD ($) $ in Thousands	Sep. 30, 2018	Dec. 31, 2017
Accounting Policies [Abstract]
Net Investment in Sales Type Leases	$ 901	$ 1,289

Revenue, deferred revenue, an_3

Revenue, deferred revenue, and deferred commissions - Consolidated Balance Sheet (Details) - USD ($) $ in Thousands	Sep. 30, 2018	Jun. 30, 2018	Dec. 31, 2017
Revenue, Initial Application Period Cumulative Effect Transition [Line Items]
Other receivables	$ 2,289		$ 1,331	[1]
Deferred commissions	9,475		10,301	[1]
Deferred revenue, current	41,410		40,734	[1]
Deferred revenue, long-term	12,898		14,417	[1]
Total deferred revenue	54,308	$ 53,408	55,151
Stockholders' equity	$ 157,377		128,000	[1]
As Reported
Revenue, Initial Application Period Cumulative Effect Transition [Line Items]
Other receivables			1,170
Deferred commissions			0
Deferred revenue, current			47,276
Deferred revenue, long-term			16,438
Total deferred revenue			63,714
Stockholders' equity			108,975
Accounting Standards Update 2014-09 | Impact of Adoption
Revenue, Initial Application Period Cumulative Effect Transition [Line Items]
Other receivables			161
Deferred commissions			10,301
Deferred revenue, current			(6,542)
Deferred revenue, long-term			(2,021)
Total deferred revenue			(8,563)
Stockholders' equity			$ 19,025
[1]	See Note 1 for a summary of adjustments related to the adoption of the new revenue recognition standard.

Revenue, deferred revenue, an_4

Revenue, deferred revenue, and deferred commissions - Consolidated Statement of Operations (Details) - USD ($) $ / shares in Units, $ in Thousands		3 Months Ended			9 Months Ended
		Sep. 30, 2018	Sep. 30, 2017		Sep. 30, 2018	Sep. 30, 2017
Revenue
Total revenue		$ 47,822	$ 45,585	[1]	$ 130,750	$ 121,869	[1]
Gross Profit		31,138	29,136	[1]	80,690	73,087
Operating expenses		30,085	27,572	[1]	87,545	83,719	[1]
Operating Income (Loss)		1,053	1,564	[1]	(6,855)	(10,632)	[1]
Net loss		(249)	$ 1,391	[1]	(8,573)	$ (11,271)	[1]
Earnings Per Share, Basic and Diluted	[1]		$ 0.05			$ (0.40)
As Reported
Revenue
Total revenue			$ 42,300			$ 117,045
Gross Profit			25,851			68,263
Operating expenses			28,563			84,500
Operating Income (Loss)			(2,712)			(16,237)
Net loss			$ (2,885)			$ (16,876)
Earnings Per Share, Basic and Diluted			$ (0.10)			$ (0.59)
Impact of Adoption
Revenue
Net loss						$ 5,605
Accounting Standards Update 2014-09 | As Reported
Revenue
Total revenue			$ 3,285			4,824
Accounting Standards Update 2014-09 | Impact of Adoption
Revenue
Gross Profit			3,285			4,824
Operating expenses			(991)			(781)
Operating Income (Loss)			4,276			5,605
Net loss			$ 4,276			$ 5,605
Earnings Per Share, Basic and Diluted			$ 0.15			$ 0.19
Product
Revenue
Total revenue		27,341	$ 26,018	[1]	70,252	$ 67,062	[1]
Product | As Reported
Revenue
Total revenue			23,249			63,940
Product | Accounting Standards Update 2014-09 | Impact of Adoption
Revenue
Total revenue			2,769			3,122
Service
Revenue
Total revenue		$ 20,481	19,567	[1]	$ 60,498	54,807	[1]
Service | As Reported
Revenue
Total revenue			19,051			53,105
Service | Accounting Standards Update 2014-09 | As Reported
Revenue
Total revenue			$ 516			$ 1,702
[1]	See Note 1 for a summary of adjustments related to the adoption of the new revenue recognition standard.

Revenue, deferred revenue, an_5

Revenue, deferred revenue, and deferred commissions - Cash Flows From Operating Activities (Details) - USD ($) $ in Thousands	3 Months Ended			9 Months Ended
	Sep. 30, 2018	Sep. 30, 2017		Sep. 30, 2018	Sep. 30, 2017
Revenue, Initial Application Period Cumulative Effect Transition [Line Items]
Net loss	$ (249)	$ 1,391	[1]	$ (8,573)	$ (11,271)	[1]
Adjustments to reconcile net loss to net cash used in operating activities:
Deferred commissions				826	(781)	[1]
Deferred revenue				$ (843)	(687)	[1]
As Reported
Revenue, Initial Application Period Cumulative Effect Transition [Line Items]
Net loss		(2,885)			(16,876)
Adjustments to reconcile net loss to net cash used in operating activities:
Deferred commissions					0
Impact of Adoption
Revenue, Initial Application Period Cumulative Effect Transition [Line Items]
Net loss					5,605
Adjustments to reconcile net loss to net cash used in operating activities:
Deferred commissions					(781)
Deferred revenue					(4,824)
Accounting Standards Update 2014-09 | Impact of Adoption
Revenue, Initial Application Period Cumulative Effect Transition [Line Items]
Net loss		$ 4,276			$ 5,605
[1]	See Note 1 for a summary of adjustments related to the adoption of the new revenue recognition standard.

Revenue, deferred revenue, an_6

Revenue, deferred revenue, and deferred commissions - Disaggregation of Revenue (Details) - USD ($) $ in Thousands	3 Months Ended			9 Months Ended
	Sep. 30, 2018	Sep. 30, 2017		Sep. 30, 2018	Sep. 30, 2017
Revenue, Initial Application Period Cumulative Effect Transition [Line Items]
Total revenue	$ 47,822	$ 45,585	[1]	$ 130,750	$ 121,869	[1]
Product Segment [Member]
Revenue, Initial Application Period Cumulative Effect Transition [Line Items]
Total revenue	27,341	26,018		70,252	67,062
Product Segment [Member] | Software [Member]
Revenue, Initial Application Period Cumulative Effect Transition [Line Items]
Total revenue	10,310	9,494		25,524	21,490
Product Segment [Member] | Device [Member]
Revenue, Initial Application Period Cumulative Effect Transition [Line Items]
Total revenue	17,031	16,524		44,728	45,572
Service Segment [Member]
Revenue, Initial Application Period Cumulative Effect Transition [Line Items]
Total revenue	20,481	19,567		60,498	54,807
Service Segment [Member] | Maintenance and Support [Member]
Revenue, Initial Application Period Cumulative Effect Transition [Line Items]
Total revenue	16,023	13,837		45,493	38,507
Service Segment [Member] | Professional Services and Training [Member]
Revenue, Initial Application Period Cumulative Effect Transition [Line Items]
Total revenue	$ 4,458	$ 5,730		$ 15,005	$ 16,300
[1]	See Note 1 for a summary of adjustments related to the adoption of the new revenue recognition standard.

Revenue, deferred revenue, an_7

Revenue, deferred revenue, and deferred commissions - Significant Changes in Deferred Commissions (Details) - USD ($) $ in Thousands	3 Months Ended	9 Months Ended
	Sep. 30, 2018	Sep. 30, 2018
Change in Contract with Customer, Asset [Roll Forward]
Beginning balance	$ 9,329	$ 10,301
Additions	1,283	3,073
Commissions Recognized	(1,137)	(3,899)
Ending balance	$ 9,475	$ 9,475

Revenue, deferred revenue, an_8

Revenue, deferred revenue, and deferred commissions - Significant Changes in Deferred Revenue (Details) - USD ($) $ in Thousands	3 Months Ended	9 Months Ended
	Sep. 30, 2018	Sep. 30, 2018
Change in Contract with Customer, Liability [Roll Forward]
Beginning balance	$ 53,408	$ 55,151
Additions	18,142	56,226
Revenue Recognized	(17,242)	(57,069)
Ending balance	$ 54,308	$ 54,308

Revenue, deferred revenue, an_9

Revenue, deferred revenue, and deferred commissions - Narrative (Details) - USD ($) $ in Thousands	3 Months Ended		9 Months Ended
	Sep. 30, 2018	Sep. 30, 2017	Sep. 30, 2018	Sep. 30, 2017	Jun. 30, 2018	Dec. 31, 2017
Revenue from Contract with Customer [Abstract]
Deferred commissions	$ 9,475		$ 9,475			$ 10,301	[1]
Payment terms on invoiced amounts			30 days
Deferred commissions	$ 9,475		$ 9,475		$ 9,329	$ 10,301
Percentage of deferred commissions to be recognized as commission expense in the next 12 months	47.90%		47.90%
Revenue recognized pertaining to amounts deferred as of December 31, 2017	$ 15,500		$ 36,900
Revenue recognized pertaining to amounts deferred as of December 31, 2016		$ 12,200		$ 27,500
Deferred revenue and backlog	$ 117,200		$ 117,200
Percentage of deferred revenue to be recognized over the next 12 months	63.00%		63.00%
[1]	See Note 1 for a summary of adjustments related to the adoption of the new revenue recognition standard.

Fair Value of Financial Instr_2

Fair Value of Financial Instruments (Details) - USD ($)	9 Months Ended
	Sep. 30, 2018	Dec. 31, 2017
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	32,971,000	$ 28,726,000
Short-term investments	181,982,000	52,507,000
U.S. government agency securities
Assets, Fair Value Disclosure [Abstract]
Short-term investments	4,630,000	8,648,000
U.S. Treasury securities
Assets, Fair Value Disclosure [Abstract]
Short-term investments	3,485,000	5,561,000
Corporate debt securities
Assets, Fair Value Disclosure [Abstract]
Short-term investments	144,553,000	37,097,000
Fair Value, Measurements, Recurring
Assets, Fair Value Disclosure [Abstract]
Total assets measured at fair value	192,886,000	56,172,000
Fair Value, Measurements, Recurring | Level 1
Assets, Fair Value Disclosure [Abstract]
Total assets measured at fair value	5,910,000	3,232,000
Fair Value, Measurements, Recurring | Level 2
Assets, Fair Value Disclosure [Abstract]
Total assets measured at fair value	186,976,000	52,940,000
Fair Value, Measurements, Recurring | U.S. government agency securities
Assets, Fair Value Disclosure [Abstract]
Short-term investments	4,630,000	8,648,000
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	4,630,000	8,648,000
Fair Value, Measurements, Recurring | U.S. Treasury securities
Assets, Fair Value Disclosure [Abstract]
Short-term investments	3,485,000	5,561,000
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	3,485,000	5,561,000
Fair Value, Measurements, Recurring | Corporate debt securities
Assets, Fair Value Disclosure [Abstract]
Short-term investments	144,553,000	37,530,000
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	144,553,000	37,530,000
Fair Value, Measurements, Recurring | Money market funds
Assets, Fair Value Disclosure [Abstract]
Cash and cash equivalents	5,910,000	3,232,000
Fair Value, Measurements, Recurring | Money market funds | Level 1
Assets, Fair Value Disclosure [Abstract]
Cash and cash equivalents	5,910,000	3,232,000
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	34,308,000	1,201,000
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	$ 34,308,000	$ 1,201,000

Schedule of Available for Sale

Schedule of Available for Sale Securities (Details) - USD ($) $ in Thousands	Sep. 30, 2018	Dec. 31, 2017
Cash and cash equivalents [Abstract]
Cash and Cash Equivalents, Amortized Cost	$ 32,972	$ 28,726
Cash And Cash Equivalents, Gross Unrealized Gains	0	0
Cash And Cash Equivalents, Gross Unrealized Losses	(1)	0
Cash and cash equivalents	32,971	28,726
Short-term Investments [Abstract]
AFS Securities, Amortized Cost Basis	182,248	52,642
Debt Securities, Available-for-sale, Accumulated Gross Unrealized Gain, before Tax	3	1
Debt Securities, Available-for-sale, Accumulated Gross Unrealized Loss, before Tax	269	136
Short-term investments	181,982	52,507
Cash, Cash Equivalents, and Short-term Investments [Abstract]
Cash, Cash Equiv. And S-T Investments, Amortized Cost	215,220	81,368
Cash, Cash Equivalents And Short Term Investments, Unrealized Gains	3	1
Cash, Cash Equivalents And Short Term Investments, Unrealized Losses	270	136
Cash, cash equivalents and short-term investments	214,953	81,233
Demand deposits and other cash
Cash and cash equivalents [Abstract]
Cash and Cash Equivalents, Amortized Cost	22,067	25,061
Cash And Cash Equivalents, Gross Unrealized Gains	0	0
Cash And Cash Equivalents, Gross Unrealized Losses	0	0
Cash and cash equivalents	22,067	25,061
Money market funds
Cash and cash equivalents [Abstract]
Cash and Cash Equivalents, Amortized Cost	5,910	3,232
Cash And Cash Equivalents, Gross Unrealized Gains	0	0
Cash And Cash Equivalents, Gross Unrealized Losses	0	0
Cash and cash equivalents	5,910	3,232
Commercial Paper in CE
Cash and cash equivalents [Abstract]
Cash and Cash Equivalents, Amortized Cost	4,995
Cash And Cash Equivalents, Gross Unrealized Gains	0
Cash And Cash Equivalents, Gross Unrealized Losses	(1)
Cash and cash equivalents	4,994
Corporate Debt Securities
Cash and cash equivalents [Abstract]
Cash and Cash Equivalents, Amortized Cost		433
Cash And Cash Equivalents, Gross Unrealized Gains		0
Cash And Cash Equivalents, Gross Unrealized Losses		0
Cash and cash equivalents		433
Commercial paper in STI
Short-term Investments [Abstract]
AFS Securities, Amortized Cost Basis	29,328	1,202
Debt Securities, Available-for-sale, Accumulated Gross Unrealized Gain, before Tax	0	0
Debt Securities, Available-for-sale, Accumulated Gross Unrealized Loss, before Tax	14	1
Short-term investments	29,314	1,201
U.S. government agency securities
Short-term Investments [Abstract]
AFS Securities, Amortized Cost Basis	4,653	8,678
Debt Securities, Available-for-sale, Accumulated Gross Unrealized Gain, before Tax	0	0
Debt Securities, Available-for-sale, Accumulated Gross Unrealized Loss, before Tax	23	30
Short-term investments	4,630	8,648
U.S. Treasury securities
Short-term Investments [Abstract]
AFS Securities, Amortized Cost Basis	3,504	5,586
Debt Securities, Available-for-sale, Accumulated Gross Unrealized Gain, before Tax	0	0
Debt Securities, Available-for-sale, Accumulated Gross Unrealized Loss, before Tax	19	25
Short-term investments	3,485	5,561
Corporate Debt Securities
Short-term Investments [Abstract]
AFS Securities, Amortized Cost Basis	144,763	37,176
Debt Securities, Available-for-sale, Accumulated Gross Unrealized Gain, before Tax	3	1
Debt Securities, Available-for-sale, Accumulated Gross Unrealized Loss, before Tax	213	80
Short-term investments	$ 144,553	$ 37,097

Contractual maturities of cash,

Contractual maturities of cash, cash equivalent and short-term investment (Details) - USD ($) $ in Thousands	Sep. 30, 2018	Dec. 31, 2017
Debt Securities, Available-for-sale [Line Items]
Cash and cash equivalents	$ 32,971	$ 28,726
Short-term investments	181,982	52,507
Cash, cash equivalents and short-term investments	214,953	81,233
Maturity up to one year
Debt Securities, Available-for-sale [Line Items]
Cash and cash equivalents	32,971	28,726
Short-term investments	117,463	34,750
Cash, cash equivalents and short-term investments	150,434	63,476
maturity between 1 and 2 years [Member]
Debt Securities, Available-for-sale [Line Items]
Cash and cash equivalents	0	0
Short-term investments	64,519	17,757
Cash, cash equivalents and short-term investments	$ 64,519	$ 17,757

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			9 Months Ended
		Sep. 30, 2018	Sep. 30, 2017		Sep. 30, 2018	Sep. 30, 2017
Earnings Per Share [Abstract]
Weighted Average Number of Shares Outstanding, Diluted		30,230	30,473		29,861	28,439
Weighted Average Number of Shares Outstanding, Basic		30,230	29,130		29,861	28,439
Numerator:
Net loss		$ (249)	$ 1,391	[1]	$ (8,573)	$ (11,271)	[1]
Net income (loss) per share
Earnings Per Share, Basic and Diluted	[1]		$ 0.05			$ (0.40)
Earnings Per Share, Basic		$ (0.01)	$ 0.05		$ (0.29)	$ (0.40)
Incremental Common Shares Attributable to Dilutive Effect of Share-based Payment Arrangements		0	1,343		0	0
Earnings Per Share, Diluted		$ (0.01)	$ 0.05		$ (0.29)	$ (0.40)
[1]	See Note 1 for a summary of adjustments related to the adoption of the new revenue recognition standard.

Schedule of antidilutive securi

Schedule of antidilutive securities excluded from computation of earnings per share (Details) - shares shares in Thousands	3 Months Ended		9 Months Ended
	Sep. 30, 2018	Sep. 30, 2017	Sep. 30, 2018	Sep. 30, 2017
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	962	2	1,176	1,735
Restricted stock units
Antidilutive Securities Excluded from Computation of Earnings Per Share [Line Items]
Antidilutive Securities Excluded from Computation of Earnings Per Share, Amount	1,911	0	1,964	2,216

Schedule of Finite-Lived Intang

Schedule of Finite-Lived Intangible Assets (Details) - USD ($) $ in Thousands	9 Months Ended
	Sep. 30, 2018	Dec. 31, 2017
Finite-Lived Intangible Assets [Line Items]
Finite-Lived Intangible Assets, Amortization Expense, Next Twelve Months	$ 3,880
Finite-Lived Intangible Assets, Amortization Expense, Year Two	1,251
Finite-Lived Intangible Assets, Amortization Expense, Year Three	1,127
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	1,001
Accumulated Amortization	13,706	$ 10,373
Finite-Lived Intangible Assets, Net	10,234
Finite-Lived Intangible Assets, Useful Life
Intangible assets, gross	23,940	23,940
Intangible assets, net book value	10,234	13,567	[1]
Developed technology
Finite-Lived Intangible Assets [Line Items]
Gross Carrying Amount	10,050	10,050
Accumulated Amortization	7,124	5,302
Finite-Lived Intangible Assets, Net	2,926	4,748
Customer relationships
Finite-Lived Intangible Assets [Line Items]
Gross Carrying Amount	10,920	10,920
Accumulated Amortization	4,351	3,469
Finite-Lived Intangible Assets, Net	6,569	7,451
Order or Production Backlog [Member]
Finite-Lived Intangible Assets [Line Items]
Gross Carrying Amount	1,400	1,400
Accumulated Amortization	1,023	650
Finite-Lived Intangible Assets, Net	377	750
Noncompete Agreements
Finite-Lived Intangible Assets [Line Items]
Gross Carrying Amount	460	460
Accumulated Amortization	460	455
Finite-Lived Intangible Assets, Net	0	5
Trademarks
Finite-Lived Intangible Assets [Line Items]
Gross Carrying Amount	1,110	1,110
Accumulated Amortization	748	497
Finite-Lived Intangible Assets, Net	$ 362	$ 613
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
[1]	See Note 1 for a summary of adjustments related to the adoption of the new revenue recognition standard.

Future amortization schedule (D

Future amortization schedule (Details) $ in Thousands	Sep. 30, 2018USD ($)
Goodwill and intangible assets [Abstract]
Finite-Lived Intangibles, AmortExp Remainder 2018	$ 1,001
Finite-Lived Intangible Assets, Amortization Expense, Next Twelve Months	3,880
Finite-Lived Intangible Assets, Amortization Expense, Year Two	1,251
Finite-Lived Intangible Assets, Amortization Expense, Year Three	1,127
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	$ 10,234

Goodwill and Intangible Asset_2

Goodwill and Intangible Assets Narrative (Details) - USD ($) $ in Thousands	3 Months Ended		9 Months Ended
	Sep. 30, 2018	Sep. 30, 2017	Sep. 30, 2018	Sep. 30, 2017	Dec. 31, 2017	[1]
Finite-Lived Intangible Assets [Line Items]
Goodwill	$ 49,246		$ 49,246		$ 49,246
Intangibles - period amortization expense [Abstract]
Amortization expense	1,000	$ 1,200	3,300	$ 3,500
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
[1]	See Note 1 for a summary of adjustments related to the adoption of the new revenue recognition standard.

Inventories (Details)

Inventories (Details) - USD ($) $ in Thousands	Sep. 30, 2018	Dec. 31, 2017
Inventory, Net [Abstract]
Raw materials	$ 274	$ 4
Finished goods	3,404	2,811
Total inventories	$ 3,678	$ 2,815	[1]
[1]	See Note 1 for a summary of adjustments related to the adoption of the new revenue recognition standard.

Property and Equipment (Details

Property and Equipment (Details) - USD ($) $ in Thousands	3 Months Ended		9 Months Ended
	Sep. 30, 2018	Sep. 30, 2017	Sep. 30, 2018	Sep. 30, 2017	Dec. 31, 2017
Property, Plant and Equipment [Line Items]
Property, Plant and Equipment, Gross	$ 20,406		$ 20,406		$ 18,171
Less: Accumulated depreciation	(13,348)		(13,348)		(12,420)
Property and equipment, net	7,058		7,058		5,751	[1]
Depreciation, Depletion and Amortization [Abstract]
Depreciation	900	$ 800	2,300	$ 2,200
Computer equipment and software
Property, Plant and Equipment [Line Items]
Property, Plant and Equipment, Gross	9,965		9,965		8,832
Furniture, fixtures and equipment
Property, Plant and Equipment [Line Items]
Property, Plant and Equipment, Gross	2,261		2,261		1,764
Leasehold improvements
Property, Plant and Equipment [Line Items]
Property, Plant and Equipment, Gross	5,819		5,819		4,794
Manufacturing tools and equipment
Property, Plant and Equipment [Line Items]
Property, Plant and Equipment, Gross	1,990		1,990		2,624
Construction in process
Property, Plant and Equipment [Line Items]
Property, Plant and Equipment, Gross	$ 371		$ 371		$ 157
[1]	See Note 1 for a summary of adjustments related to the adoption of the new revenue recognition standard.

Investment in Sales Type Leases

Investment in Sales Type Leases (Details) - USD ($) $ in Thousands	9 Months Ended
	Sep. 30, 2018	Dec. 31, 2017
Capital Leased Assets [Line Items]
Net Investment in Sales Type Leases, Future Minimum Payments-Gross	$ 2,246	$ 2,758
Net Investment in Sales Type Leases, Deferred Income	(1,345)	(1,469)
Net Investment in Sales Type Leases	901	1,289
Net Investment in Sales Type Leases, Current	(525)	(916)
Net Investment in Sales Type Leases, Noncurrent	$ 376	$ 373
Minimum
Capital Leased Assets [Line Items]
Lessors, Capital Leases, Term of contract	2 years
Maximum
Capital Leased Assets [Line Items]
Lessors, Capital Leases, Term of contract	4 years

Future payments- sales type lea

Future payments- sales type leases (Details) - USD ($) $ in Thousands	Sep. 30, 2018	Dec. 31, 2017
Balance Sheet Components [Abstract]
Future Minimum Payments, Remainder of Fiscal Year	$ 395
Capital Leases, Future Minimum Payments Due in 2019	1,038
Capital Leases, Future Minimum Payments Due in Two Years	649
Sales-type Leases, Future Minimum Payments Due in 2021	139
Capital Leases, Future Minimum Payments Due in 2022	25
Net Investment in Sales Type Leases, Future Minimum Payments-Gross	$ 2,246	$ 2,758

Accrued Liabilities (Details)

Accrued Liabilities (Details) - USD ($) $ in Thousands	Sep. 30, 2018	Dec. 31, 2017
Accrued Liabilities, Current [Abstract]
Payroll and related expenses	$ 6,921	$ 9,569
Accrued payables	2,487	1,801
Deferred Rent Credit, Current	301	271
Lease financing, current portion	915	832
Product warranty	351	353
Customer Refund Liability, Current	650	1,084
Sales and use tax payable	505	505
Other	1,328	274
Total accrued payroll and other current liabilities	$ 13,458	$ 14,689	[1]
[1]	See Note 1 for a summary of adjustments related to the adoption of the new revenue recognition standard.

Schedule of Product Liability (

Schedule of Product Liability (Details) - USD ($) $ in Thousands	3 Months Ended		9 Months Ended
	Sep. 30, 2018	Sep. 30, 2017	Sep. 30, 2018	Sep. 30, 2017	Dec. 31, 2016
Movement in Standard and Extended Product Warranty, Increase (Decrease) [Roll Forward]
Product warranty accrual, at the beginning of the period	$ 306	$ 315	$ 353
Warranty expenses accrued	131	118	345	$ 376
Product Warranty Accrual, Preexisting, Increase (Decrease)	(45)	(49)	(179)	(426)
Warranty settlements made	(41)	(73)	(168)	(235)
Product Warranty Accrual	$ 351	$ 311	$ 351	$ 311	$ 596

Convertible Senior Notes - Conv

Convertible Senior Notes - Convertible Notes and Options (Details)	Sep. 28, 2018USD ($)$ / shares	May 31, 2018USD ($)day$ / shares	Jun. 30, 2018USD ($)	Sep. 30, 2018USD ($)	Sep. 30, 2017USD ($)	[1]	Sep. 30, 2018USD ($)	Sep. 30, 2017USD ($)	[1]	Dec. 31, 2017USD ($)	[1]
Debt Instrument [Line Items]
Proceeds from issuance of convertible senior notes, net of issuance costs							$ 138,854,000	$ 0
Net carrying amount				$ 108,942,000			108,942,000			$ 0
Total interest expense				2,106,000	$ 0		3,103,000	$ 0
Convertible Debt | Convertible Senior Notes at 1.50%
Debt Instrument [Line Items]
Aggregate principal amount		$ 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				(31,282,000)			(31,282,000)
Unamortized issuance costs				(3,526,000)			(3,526,000)
Net carrying amount				108,942,000			108,942,000
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
Debt discount effective interest rate			7.60%
Amortization of debt issuance costs			$ 4,900,000	159,000			233,000
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)
Net carrying amount				32,214,000			32,214,000
Estimated fair value of the Notes				178,600,000			178,600,000
Denominator in closing price calculation				100			100
If-converted value, share price (in dollars per share) | $ / shares	$ 36.58
If-converted value of the Notes	$ 163,100,000
Contractual interest expense				539,000			803,000
Amortization of debt discount				1,408,000			2,067,000
Total interest expense				$ 2,106,000			$ 3,103,000
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%
[1]	See Note 1 for a summary of adjustments related to the adoption of the new revenue recognition standard.

Convertible Senior Notes - Capp

Convertible Senior Notes - Capped Calls (Details) - USD ($) $ / shares in Units, $ in Thousands, shares in Millions	1 Months Ended	9 Months Ended
	May 31, 2018	Sep. 30, 2018	Sep. 30, 2017	[1]
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)	$ 0
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
Carrying amount of equity component, net of capped calls		$ 23,307
[1]	See Note 1 for a summary of adjustments related to the adoption of the new revenue recognition standard.

Schedule of Future Minimum Rent

Schedule of Future Minimum Rental Payments for Operating Leases (Details) - USD ($) $ in Thousands	3 Months Ended		9 Months Ended
	Sep. 30, 2018	Sep. 30, 2017	Sep. 30, 2018	Sep. 30, 2017
Commitments and Contingencies Disclosure [Abstract]
Operating Leases, Rent Expense, Net	$ 700	$ 600	$ 2,000	$ 1,900
Operating Leases, Future Minimum Payments Due, by FY
Remainder of 2016	582		582
Operating Leases, Future Minimum Payments, 2017	2,222		2,222
Operating Leases, Future Minimum Payments, 2018	2,078		2,078
Operating Leases, Future Minimum Payments, 2019	1,837		1,837
Operating Leases, Future Minimum Payments, 2020	612		612
Operating Leases, Future Minimum Payments, 2021	35		35
Total minimum lease payments	$ 7,366		$ 7,366

Commitments Narrative (Details)

Commitments Narrative (Details) - USD ($) $ in Millions	3 Months Ended		9 Months Ended
	Sep. 30, 2018	Sep. 30, 2017	Sep. 30, 2018	Sep. 30, 2017	Dec. 31, 2017
Unrecorded Unconditional Purchase Obligation [Line Items]
Operating Leases, Rent Expense, Net	$ 0.7	$ 0.6	$ 2	$ 1.9
Inventories
Unrecorded Unconditional Purchase Obligation [Line Items]
Unrecorded Unconditional Purchase Obligation	$ 10.9		$ 10.9		$ 4.4

Stock Option Activity (Details)

Stock Option Activity (Details) - Stock Options - USD ($) $ / shares in Units, $ in Thousands	9 Months Ended	12 Months Ended
	Sep. 30, 2018	Dec. 31, 2017
Number of Options (in shares):
Beginning balance	1,332,063
Options granted	0
Options exercised	(435,326)
Options canceled	(2,774)
Ending balance	893,963	1,332,063
Weighted Average Exercise Price (in dollars per share):
Beginning balance	$ 13.48
Options granted	0
Options exercised	14.79
Options canceled	4.97
Ending balance	$ 12.88	$ 13.48
Wtd avg remaining term, Outstanding	4 years 10 months 17 days	5 years 4 months 10 days
Aggregate intrinsic value, Outstanding	$ 21,191	$ 22,298

Summary of Equity B-S-M Assumpt

Summary of Equity B-S-M Assumptiuons (Details) - 2012 Employee Stock Purchase Plan - ESPP	3 Months Ended		9 Months Ended
	Sep. 30, 2018	Sep. 30, 2017	Sep. 30, 2018	Sep. 30, 2017
Equity B-S-M Fair Value Assumptions
Expected Term (in years)	6 months	6 months	6 months	6 months
Volatility		30.00%
Interest Rate		1.02%
Dividend yield	0.00%	0.00%	0.00%	0.00%
Minimum
Equity B-S-M Fair Value Assumptions
Expected Term (in years)
Volatility			29.00%	30.00%
Interest Rate			1.39%	0.61%
Maximum
Equity B-S-M Fair Value Assumptions
Expected Term (in years)
Volatility			37.80%	32.00%
Interest Rate			2.09%	1.02%

Summary of Restricted Stock Act

Summary of Restricted Stock Activity (Details) - Restricted Stock Units	9 Months Ended
	Sep. 30, 2018$ / 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 8 months 24 days
Number of Shares:
Beginning balance | shares	2,045,589
Granted | shares	837,571
Vested | shares	(865,397)
Forfeited | shares	(107,039)
Ending balance | shares	1,910,724
Weighted Average Grant Date Fair Value per Share (in dollars per share):
Beginning balance | $ / shares	$ 18.84
Granted | $ / shares	25.94
Vested | $ / shares	17.09
Forfeited | $ / shares	21.10
Ending balance | $ / shares	$ 22.61

Share-based Compensaton Allocat

Share-based Compensaton Allocated to Expense Captions (Details) - USD ($) $ in Thousands	3 Months Ended		9 Months Ended
	Sep. 30, 2018	Sep. 30, 2017	Sep. 30, 2018	Sep. 30, 2017
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Stock-based compensation expense	$ 5,494	$ 4,718	$ 15,477	$ 13,204
Cost of Sales
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Stock-based compensation expense	923	749	2,636	2,117
Research and Development Expense
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Stock-based compensation expense	802	507	2,164	1,542
Selling and Marketing Expense
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Stock-based compensation expense	1,755	1,653	4,906	4,697
General and Administrative Expense
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Stock-based compensation expense	$ 2,014	$ 1,809	$ 5,771	$ 4,848

Narrative (Details)

Narrative (Details) - USD ($) $ / shares in Units, $ in Millions	9 Months Ended
	Sep. 30, 2018	Sep. 30, 2017	Jun. 30, 2017
ESPP plan details [Abstract]
Stock Issued During Period, Shares, Employee Stock Purchase Plans	78,563	89,813
Stock Options
Share-based Compensation Arrangement by Share-based Payment Award, Options, Additional Disclosures [Abstract]
Unamortized Compensation Cost, Stock Options	$ 0.1
Uamortized Compensation Cost Not yet Recognized, Period Remaining, Options	5 months 11 days
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	$ 33.4
Stock Comp-other than options - Period for Recognition- Comp cost not yet rocognized	1 year 8 months 24 days
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	2,375,322
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	$ 20.69		$ 13.87
Common Stock, Capital Shares Reserved for Future Issuance	800,166

Segments Operating Segments (De

Segments Operating Segments (Details) $ in Thousands	3 Months Ended			9 Months Ended
	Sep. 30, 2018USD ($)	Sep. 30, 2017USD ($)		Sep. 30, 2018USD ($)Segments	Sep. 30, 2017USD ($)
Segment Reporting Information [Line Items]
Number of reportable segments | Segments				2
Revenue
Total revenue	$ 47,822	$ 45,585	[1]	$ 130,750	$ 121,869	[1]
Cost of revenue
Total cost of revenue	16,684	16,449	[1]	50,060	48,782
Gross profit
Product	20,522	18,810		50,405	46,638
Service	10,616	10,326		30,285	26,449
Total gross profit	31,138	29,136	[1]	80,690	73,087
Calculation of pretax profit (loss) [Abstract]
Operating expenses	30,085	27,572	[1]	87,545	83,719	[1]
Interest income (expense), net and other	(1,154)	136		(2,213)	411
Loss before income taxes	(101)	1,700	[1]	(9,068)	(10,221)	[1]
Product
Revenue
Total revenue	27,341	26,018	[1]	70,252	67,062	[1]
Cost of revenue
Total cost of revenue	6,819	7,208	[1]	19,847	20,424
Service
Revenue
Total revenue	20,481	19,567	[1]	60,498	54,807	[1]
Cost of revenue
Total cost of revenue	$ 9,865	$ 9,241	[1]	$ 30,213	$ 28,358
[1]	See Note 1 for a summary of adjustments related to the adoption of the new revenue recognition standard.

Income Taxes (Details)

Income Taxes (Details) - USD ($) $ in Thousands	3 Months Ended			9 Months Ended
	Sep. 30, 2018	Sep. 30, 2017		Sep. 30, 2018	Sep. 30, 2017
Income Tax Disclosure [Abstract]
Income Tax Expense (Benefit)	$ 148	$ 309	[1]	$ (495)	$ 1,050	[1]
[1]	See Note 1 for a summary of adjustments related to the adoption of the new revenue recognition standard.