RingCentral (RNG) 10-K 29 Feb 16 2015 FY Annual report Financial data

Document and Entity Information

Document and Entity Information - USD ($) $ in Millions	12 Months Ended
	Dec. 31, 2015	Feb. 22, 2016	Jun. 30, 2015
Document And Entity Information [Line Items]
Document Type	10-K
Amendment Flag	false
Document Period End Date	Dec. 31, 2015
Document Fiscal Year Focus	2,015
Document Fiscal Period Focus	FY
Trading Symbol	RNG
Entity Registrant Name	RingCentral Inc
Entity Central Index Key	1,384,905
Current Fiscal Year End Date	--12-31
Entity Well-known Seasoned Issuer	No
Entity Current Reporting Status	Yes
Entity Voluntary Filers	No
Entity Filer Category	Large Accelerated Filer
Entity Public Float			$ 1,040
Class A common stock
Document And Entity Information [Line Items]
Entity Common Stock, Shares Outstanding		58,576,208
Class B common stock
Document And Entity Information [Line Items]
Entity Common Stock, Shares Outstanding		13,430,733

CONSOLIDATED BALANCE SHEETS

CONSOLIDATED BALANCE SHEETS - USD ($) $ in Thousands	Dec. 31, 2015	Dec. 31, 2014
Current assets:
Cash and cash equivalents	$ 137,588	$ 113,182
Short-term investments		28,479
Accounts receivable, net	19,163	7,651
Inventory	2,317	1,710
Prepaid expenses and other current assets	11,978	8,767
Total current assets	171,046	159,789
Property and equipment, net	28,160	25,527
Goodwill	9,393
Acquired intangibles, net	3,266
Other assets	2,948	3,021
Total assets	214,813	188,337
Current liabilities:
Accounts payable	5,196	4,181
Accrued liabilities	34,702	29,236
Current portion of capital lease obligation	269	509
Current portion of long-term debt	3,750	16,764
Deferred revenue	36,657	25,586
Total current liabilities	80,574	76,276
Long-term debt	14,840	7,813
Sales tax liability	3,670	3,953
Capital lease obligation	181	535
Other long-term liabilities	5,416	3,255
Total liabilities	$ 104,681	$ 91,832
Commitments and contingencies (Note 6)
Stockholders' equity:
Additional paid-in capital	$ 319,792	$ 274,844
Accumulated other comprehensive income (loss)	527	(251)
Accumulated deficit	(210,194)	(178,095)
Total stockholders' equity	110,132	96,505
Total liabilities and stockholders' equity	214,813	188,337
Class A common stock
Stockholders' equity:
Common stock	6	5
Class B common stock
Stockholders' equity:
Common stock	$ 1	$ 2

CONSOLIDATED BALANCE SHEETS (Pa

CONSOLIDATED BALANCE SHEETS (Parenthetical) - $ / shares	Dec. 31, 2015	Dec. 31, 2014
Class A common stock
Common stock, par or stated value per share	$ 0.0001	$ 0.0001
Common stock, shares authorized	1,000,000,000	1,000,000,000
Common stock, shares issued	58,480,000	50,770,000
Common stock, shares outstanding	58,480,000	50,770,000
Class B common stock
Common stock, par or stated value per share	$ 0.0001	$ 0.0001
Common stock, shares authorized	250,000,000	250,000,000
Common stock, shares issued	13,483,000	17,789,000
Common stock, shares outstanding	13,483,000	17,789,000

CONSOLIDATED STATEMENTS OF OPER

CONSOLIDATED STATEMENTS OF OPERATIONS - USD ($) shares in Thousands, $ in Thousands	12 Months Ended
	Dec. 31, 2015	Dec. 31, 2014	Dec. 31, 2013
Revenues:
Software subscriptions	$ 271,245	$ 200,098	$ 145,995
Product	24,983	19,789	14,510
Total revenues	296,228	219,887	160,505
Cost of revenues:
Software subscriptions	66,354	58,673	47,230
Product	20,917	18,100	14,289
Total cost of revenues	87,271	76,773	61,519
Gross profit	208,957	143,114	98,986
Operating expenses:
Research and development	52,924	44,582	33,399
Sales and marketing	139,851	104,827	72,336
General and administrative	47,114	38,910	34,284
Total operating expenses	239,889	188,319	140,019
Loss from operations	(30,932)	(45,205)	(41,033)
Other income (expense), net:
Interest expense	(1,123)	(2,007)	(5,384)
Other income (expense), net	(1,307)	(1,031)	274
Other income (expense), net	(2,430)	(3,038)	(5,110)
Loss before provision (benefit) for income taxes	(33,362)	(48,243)	(46,143)
Provision (benefit) for income taxes	(1,263)	97	(45)
Net loss	$ (32,099)	$ (48,340)	$ (46,098)
Net loss per common share:
Basic and diluted	$ (0.46)	$ (0.72)	$ (1.39)
Weighted-average number of shares used in computing net loss per share:
Basic and diluted	70,069	66,818	33,155

CONSOLIDATED STATEMENTS OF COMP

CONSOLIDATED STATEMENTS OF COMPREHENSIVE LOSS - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2015	Dec. 31, 2014	Dec. 31, 2013
Statement Of Income And Comprehensive Income [Abstract]
Net loss	$ (32,099)	$ (48,340)	$ (46,098)
Other comprehensive loss:
Foreign currency translation adjustments, net	561	276	(225)
Unrealized gain (loss) on available-for-sale securities	217	(217)
Comprehensive loss, net of taxes	$ (31,321)	$ (48,281)	$ (46,323)

CONSOLIDATED STATEMENTS OF STOC

CONSOLIDATED STATEMENTS OF STOCKHOLDERS' EQUITY - USD ($) shares in Thousands, $ in Thousands	Total	Convertible Preferred Stock	Common Stock	Additional Paid-in Capital	Accumulated Other Comprehensive Loss	Accumulated Deficit
Beginning Balance at Dec. 31, 2012	$ 71	$ 74,020	$ 2	$ 9,791	$ (85)	$ (83,657)
Beginning Balance, shares at Dec. 31, 2012		30,369	22,694
Issuance of common stock upon exercise and early exercise of stock options	1,007			1,007
Issuance of common stock upon exercise and early exercise of stock options, shares			616
Issuance of common stock for legal settlement	257			257
Issuance of common stock for legal settlement, shares			20
Issuance of preferred stock warrants in connection with a debt agreement	866			866
Reclassification of preferred stock warrant	820			820
Conversion of preferred stock into common stock in connection with IPO		$ (74,020)	$ 3	74,017
Conversion of preferred stock into common stock in connection with IPO, shares		(30,369)	30,369
Issuance of stock	99,277		$ 1	99,276
Issuance of stock, shares			8,545
Share-based compensation	7,540			7,540
Changes in comprehensive loss	(225)				(225)
Net loss	(46,098)					(46,098)
Ending Balance at Dec. 31, 2013	63,515		$ 6	193,574	(310)	(129,755)
Ending Balance, shares at Dec. 31, 2013			62,244
Issuance of stock	56,117			56,117
Issuance of stock, shares			2,792
Issuance of common stock in connection with Equity Incentive and Employee Stock Purchase plans	9,638		$ 1	9,637
Issuance of common stock in connection with Equity Incentive and Employee Stock Purchase plans, shares			3,523
Share-based compensation	15,516			15,516
Changes in comprehensive loss	59				59
Net loss	(48,340)					(48,340)
Ending Balance at Dec. 31, 2014	96,505		$ 7	274,844	(251)	(178,095)
Ending Balance, shares at Dec. 31, 2014			68,559
Issuance of common stock in connection with Equity Incentive and Employee Stock Purchase plans	19,413			19,413
Issuance of common stock in connection with Equity Incentive and Employee Stock Purchase plans, shares			3,181
Issuance of shares of business acquisition	3,447			3,447
Issuance of shares of business acquisition, shares			223
Share-based compensation	22,088			22,088
Changes in comprehensive loss	778				778
Net loss	(32,099)					(32,099)
Ending Balance at Dec. 31, 2015	$ 110,132		$ 7	$ 319,792	$ 527	$ (210,194)
Ending Balance, shares at Dec. 31, 2015			71,963

CONSOLIDATED STATEMENTS OF STO7

CONSOLIDATED STATEMENTS OF STOCKHOLDERS' EQUITY (Parenthetical) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2014	Dec. 31, 2013
Common Stock
Issuance costs	$ 1,050	$ 11,809

CONSOLIDATED STATEMENTS OF CASH

CONSOLIDATED STATEMENTS OF CASH FLOWS - USD ($)	12 Months Ended
	Dec. 31, 2015	Dec. 31, 2014	Dec. 31, 2013
Cash flows from operating activities:
Net loss	$ (32,099,000)	$ (48,340,000)	$ (46,098,000)
Adjustments to reconcile net loss to net cash used in operating activities:
Depreciation and amortization	13,467,000	10,378,000	8,980,000
Share-based compensation	22,088,000	15,516,000	7,540,000
Tax benefit from release of valuation allowance	(1,411,000)
Impairment of fixed assets	1,317,000	0	0
Non-cash interest and other expense related to debt	156,000	259,000	2,014,000
Net accretion of discount and amortization of premium on available-for-sale securities	616,000
Allowance for doubtful accounts	411,000	40,000
Loss on disposal of assets	322,000	100,000	338,000
Deferred income tax	(8,000)	(35,000)	(16,000)
Others	94,000
Changes in assets and liabilities:
Accounts receivable	(11,923,000)	(4,646,000)	(355,000)
Inventory	(606,000)	401,000	(1,279,000)
Prepaid expenses and other current assets	(3,636,000)	(3,553,000)	(1,873,000)
Other assets	421,000	(1,012,000)	(328,000)
Accounts payable	1,591,000	(510,000)	(453,000)
Accrued liabilities	2,354,000	9,054,000	1,370,000
Deferred revenue	11,071,000	9,034,000	5,262,000
Other liabilities	861,000	1,884,000	1,127,000
Net cash provided by (used in) operating activities	5,086,000	(11,430,000)	(23,771,000)
Cash flows from investing activities:
Proceeds from the maturity of available-for-sale securities	28,080,000
Purchases of available-for-sale securities		(28,696,000)
Purchases of property and equipment	(14,631,000)	(17,267,000)	(10,789,000)
Cash paid for business combination, net of cash acquired	(4,670,000)
Capitalized internal-use software	(2,513,000)	(698,000)
Restricted investments	100,000		(130,000)
Net cash provided by (used in) investing activities	6,366,000	(46,661,000)	(10,919,000)
Cash flows from financing activities:
Net proceeds from public offerings of common stock		57,167,000	103,309,000
Net proceeds from debt agreements			37,857,000
Proceeds from issuance of stock in connection with stock plans	19,524,000	9,487,000	893,000
Repayment of debt	(6,142,000)	(9,909,000)	(26,309,000)
Repayment of capital lease obligations	(594,000)	(698,000)	(422,000)
Proceeds from issuance of preferred stock warrants			1,625,000
Taxes paid related to net share settlement of equity awards	(151,000)	(41,000)
Payment of offering costs		(1,219,000)	(3,720,000)
Net cash provided by financing activities	12,637,000	54,787,000	113,233,000
Effect of exchange rate changes on cash and cash equivalents	317,000	108,000	(29,000)
Net increase (decrease) in cash and cash equivalents	24,406,000	(3,196,000)	78,514,000
Cash and cash equivalents
Beginning of period	113,182,000	116,378,000	37,864,000
End of period	137,588,000	113,182,000	116,378,000
Supplemental disclosure of cash flow data:
Cash paid for interest	1,893,000	1,267,000	2,437,000
Cash paid for income taxes	100,000	96,000	46,000
Noncash investing and financing activities:
Change in liability for unvested exercised options	38,000	47,000	114,000
Accrued liability for deferred offering costs			313,000
Conversion of convertible preferred stock into common stock			74,020,000
Reclassification of preferred stock warrants from liability to equity			820,000
Issuance of common stock for business combination	3,447,000
Equipment purchased and unpaid at period end	719,000	1,013,000	$ 775,000
Equipment acquired under capital lease		1,149,000
Change in unrealized gain (loss) on available-for-sale securities	$ 217,000	$ (217,000)

Description of Business and Sum

Description of Business and Summary of Significant Accounting Policies	12 Months Ended
	Dec. 31, 2015
Organization Consolidation And Presentation Of Financial Statements [Abstract]
Description of Business and Summary of Significant Accounting Policies	Note 1. Description of Business and Summary of Significant Accounting Policies Description of Business RingCentral, Inc. (the Company) is a provider of software-as-a-service (SaaS) solutions for business communications. The Company was incorporated in California in 1999 and was reincorporated in Delaware on September 26, 2013. Public Offerings On October 2, 2013, the Company completed an initial public offering (IPO) and sold 8,625,000 shares of Class A common stock to the public, including the underwriters’ overallotment option of 1,125,000 shares of Class A common stock and 80,000 shares of Class A common stock sold by selling stockholders, at a price of $13.00 per share. The offer and sale of all of the shares in the IPO were registered under the Securities Act pursuant to a registration statement on Form S-1 (File No. 333-190815) (the “Initial Registration Statement”). The Company received aggregate proceeds of $103.3 million from the IPO, net of underwriters’ discounts and commissions, but before deduction of offering expenses of approximately $3.9 million. On March 11, 2014, the Company completed a secondary public offering and sold 7,991,551 shares of Class A common stock to the public, including 791,551 of the underwriters’ overallotment option and 5,200,000 shares of Class A common stock sold by selling stockholders, at a price of $21.50 per share. The offer and sale of all of the shares in the secondary public offering were registered under the Securities Act pursuant to a registration statement on Form S-1 (File No. 333-194132) (Secondary Registration Statement). The Company received aggregate proceeds of $57.2 million from the secondary public offering, net of underwriters’ discounts and commissions, but before deduction of offering expenses of approximately $1.1 million. The Company did not receive any proceeds from the sale of shares by the selling stockholders. Principles of Consolidation The accompanying consolidated financial statements have been prepared in accordance with U.S. generally accepted accounting principles (GAAP) and include the consolidated accounts of the Company and its wholly-owned subsidiaries. All intercompany accounts and transactions have been eliminated in consolidation. Use of Estimates The preparation of financial statements in conformity with U.S. GAAP requires management 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 revenues and expenses during the reporting period. The significant estimates made by management affect revenues, accounts receivable, the allowance for doubtful accounts, inventory reserves, goodwill, share-based compensation, deferred revenue, return reserves, provision for income taxes, uncertain tax positions, loss contingencies, sales tax liabilities and accrued liabilities. Management periodically evaluates such estimates and they are adjusted prospectively based upon such periodic evaluation. Actual results could differ from those estimates. Foreign Currency The functional currency of the Company’s foreign subsidiaries is generally the local currency. Adjustments resulting from translating foreign functional currency financial statements into U.S. dollars are recorded as part of a separate component of stockholders’ equity and reported in the statements of comprehensive loss. All assets and liabilities denominated in a foreign currency are translated into U.S. dollars at the exchange rate on the balance sheet date. Revenues and expenses are translated at the average exchange rate during the period. Foreign currency transaction gains and losses are included in other income (expense), net for the period. Cash, Cash Equivalents and Investments in Marketable Securities The Company considers highly liquid investments with a remaining maturity of three months or less at the date of purchase to be cash equivalents. The Company’s cash equivalents consist of money market funds. Cash equivalents are stated at cost plus accrued interest, which approximates fair value. Management determines the appropriate classification of its investments in marketable securities at the time of purchase and reevaluates such designation at each balance sheet date. At December 31, 2015, the Company’s cash equivalents consist of money market funds and it held no marketable securities. At December 31, 2014 the Company’s marketable securities consisted of investments in commercial paper and corporate debt securities. At December 31, 2014, all investments were designated as available-for-sale and reported at fair value based either upon quoted prices in active markets, quoted prices in less active markets, or quoted market prices for similar investments, with unrealized gains and losses, net of related tax, if any, included in accumulated other comprehensive loss in the consolidated balance sheet. These securities at any time can be liquidated for use in current operations or for other purposes, such as consideration for acquisitions, even if they had not yet reached maturity. As a result, all of our investments held at December 31, 2014 were classified as current assets in the accompanying consolidated balance sheet. The Company monitors its investments for potential impairment on a quarterly basis. When the carrying amount of an investment in any securities exceeds its fair value and the decline in value is determined to be other-than-temporary (i.e., when the Company does intend to sell the securities and it is more likely than not that the Company will be required to sell the securities prior to anticipated recovery of its amortized cost basis), management records an impairment charge to other income (expense), net, in the amount of the credit loss and the balance, if any, is recorded in accumulated other comprehensive loss in the consolidated balance sheets. No impairment losses have been recognized for the years ended December 31, 2015, 2014 and 2013. Allowance for Doubtful Accounts For the year ended December 31, 2013, a significant portion of revenues were realized from credit card transactions with only a small portion of revenues generating accounts receivable. For the years ended December 31, 2014 and 2015, the portion of revenues generating accounts receivable has increased as the Company’s larger customers are extended standard net 30 credit terms. For all periods presented, the Company has not experienced any significant defaults on its accounts receivable. The Company determines provisions based on historical experience and upon a specific review of customer receivables. Below is a summary of the changes in allowance for doubtful accounts for the years ended December 31, 2015, 2014 and 2013 (in thousands): Balance at Beginning of Period Provision, net of Recoveries Write-offs Balance at End of Period Year ended December 31, 2015 Allowance for doubtful accounts $ 125 $ 411 $ 159 $ 377 Year ended December 31, 2014 Allowance for doubtful accounts $ 139 $ 40 $ 54 $ 125 Year ended December 31, 2013 Allowance for doubtful accounts $ 433 $ (8 ) $ 286 $ 139 Inventory The Company’s inventory consists primarily of telephones and peripheral equipment held at third parties. Inventory is stated at the lower of cost computed on a first-in, first-out basis, or market value. Inventory write-downs are recorded when the cost of inventory exceeds its net realizable value and establishes a new cost basis for the inventory. On a quarterly and annual basis, the Company analyzes inventory on a part by part basis in comparison to forecasted demand to identify potential excess and obsolescence issues, and adjusts carrying amounts to estimated net realizable value accordingly. Internal-Use Software Development Costs The Company capitalizes qualifying internal-use software development costs that are incurred during the application development stage, provided that management with the relevant authority authorizes and commits to the funding of the project and it is probable the project will be completed and the software will be used to perform the function intended. Costs related to preliminary project activities and post implementation operation activities are expensed as incurred. Capitalized internal-use software development costs are included in property and equipment and are amortized on a straight-line basis to cost of revenues when the underlying project is ready for its intended use. In the fourth quarter of fiscal 2015, the Company determined that due to delays in the development and failure to achieve significant milestones by a third party supplier, certain software for internal use was no longer usable, and recorded a $1.3 million charge to the consolidated statements of operations. For the years ended December 31, 2015 and 2014, the Company capitalized $2.1 million and $0.7 million, net of impairment, of internal-use software development costs incurred, respectively. The carrying value of internal-use software development costs, net of amortization, was $2.6 million and $1.7 million at December 31, 2015 and 2014, respectively. Property and Equipment, Net Property and equipment, net is stated at cost, less accumulated depreciation and amortization, and is depreciated using the straight-line method over the estimated useful lives of the assets. Computer hardware and software, and furniture and fixtures are depreciated over useful lives ranging from three to five years; internal-use software development costs are amortized over useful lives ranging from three to four years; and leasehold improvements are depreciated over the respective lease term or useful life, whichever is shorter. Maintenance and repairs are charged to expense as incurred. The Company evaluates the recoverability of property and equipment for possible impairment whenever events or circumstances indicate that the carrying amount of such assets or asset groups may not be recoverable. Recoverability of these assets is measured by a comparison of the carrying amounts to the future undiscounted cash flows of the assets or asset groups are expected to generate. If such evaluation indicates that the carrying amount of the assets or asset groups is not recoverable, the carrying amount of such assets or asset groups is reduced to its estimated fair value. In the fourth quarter of fiscal 2015, the Company determined that due to delays in the development and failure to achieve significant milestones by a third party supplier, certain software for internal use was no longer usable, and recorded a $1.3 million charge to the consolidated statements of operations. Concentrations Financial instruments that subject the Company to concentrations of credit risk consist primarily of cash, cash equivalents, investments in marketable securities, and accounts receivable. The Company maintains its cash, cash equivalent and investment balances, which may exceed federally insured limits, with financial institutions and corporate entities that complies with investment guidelines which management believes are financially sound and have minimal credit risk exposure. The Company’s accounts receivable are primarily derived from sales by resellers and to larger direct customers. The Company performs ongoing credit evaluations of its resellers and does not require collateral on accounts receivable. The Company maintains an allowance for doubtful accounts for estimated potential credit losses. At December 31, 2015 and 2014, AT&T, one of our resellers, accounted for 39% and 44% of the Company’s total accounts receivable, respectively. For the years ended December 31, 2015 and 2014, AT&T accounted for 13% and 12% of the Company’s total revenues and 12% and 11% of our software subscription revenues, respectively. For the year ended December 31, 2013, no single customer or reseller accounted for greater than 10% of the Company’s total revenues. The Company contracted a significant portion of its software development efforts from third-party vendors located in Russia and Ukraine during the years ended December 31, 2015, 2014 and 2013, respectively. A cessation of services provided by these vendors could result in a disruption to the Company’s research and development efforts. Revenue Recognition The Company’s revenues consist primarily of software subscriptions and product revenues. The Company’s software subscriptions revenue includes all fees billed in connection with subscriptions to the Company’s RingCentral Office, RingCentral Professional, RingCentral Fax, and RingCentral Contact Center SaaS applications. These software subscription fees include recurring fixed plan subscription fees, recurring administrative cost recovery fees, variable usage-based fees for blocks of additional minutes systematically purchased in advance of usage in excess of plan limits and one-time upfront fees. The Company provides its subscriptions pursuant to contractual arrangements that range in duration from one month to three years. The Company’s subscription fees are generally billed in advance directly to customer credit cards or via invoices issued to larger customers. The Company’s product revenue consists of sales of pre-configured office phones used in connection with the service and includes shipping and handling fees. The Company recognizes revenue when the following criteria are met: · there is persuasive evidence of an arrangement; · the subscription is being provided to the customer or the product has been delivered; · the collection of the fees is reasonably assured; and · the amount of fees to be paid by the customer is fixed or determinable. Revenue under subscription plans are recognized as follows: · fixed plan subscription and administrative cost recovery fees are recognized on a straight-line basis over their respective contractual subscription terms; · fees for additional minutes of usage in excess of plan limits are recognized over the estimated usage period in a manner that approximates actual usage; and · one-time upfront fees are initially deferred and recognized on a straight-line basis over the estimated average customer life. Product revenue is billed at the time the order is received and recognized when the product has been delivered to the customer. The Company enters into arrangements with multiple-elements that generally include services to be provided under the subscription plan and the sale of products used in connection with the Company’s subscriptions. The Company allocates the consideration to each deliverable in a multiple-deliverable arrangement based upon its relative selling prices. The Company determines the selling price using vendor-specific objective evidence (VSOE) for its subscription plans and best estimated selling price (BESP) for its product offerings. Consideration allocated to each deliverable, limited to the amount not contingent on future performance, are then recognized to revenue when the basic revenue recognition criteria are met for the respective deliverable. The Company determines VSOE based on historical standalone sales to customers. In determining VSOE, the Company requires that a substantial majority of the selling prices fall within a reasonably narrow pricing range. VSOE exists for all of the Company’s subscription plans. The Company uses BESP as the selling price for its product offerings as the Company is not able to determine VSOE of fair value from standalone sales or third-party evidence of selling price (TPE). The Company estimates BESP for a product by considering company-specific factors such as pricing objectives, direct product and other costs, bundling and discounting practices and contractually stated prices. A portion of the Company’s software subscriptions and product revenues are generated through sales by resellers. When the Company assumes a majority of the business risks associated with performance of the contractual obligations, it records these revenues at the gross amount paid by the customer with amounts retained by the resellers recognized as sales and marketing expense. The Company’s assumption of such business risks is evidenced when, among other things, it takes responsibility for delivery of the product or subscription, is involved in establishing pricing of the arrangement, assumes credit and inventory risk, and is the primary obligor in the arrangement. When a reseller assumes the majority of the business risks associated with the performance of the contractual obligations, the Company records the associated revenue at the net amount received from the reseller. The Company recognizes revenue from resellers when the following criteria are met: · persuasive evidence of an arrangement exists through a contract with the customer; · the subscription is being provided to the customer or the product has been delivered; · the amount of fees to be paid by the customer is fixed or determinable; and · the collection of the fees is reasonably assured. The Company’s deliverables sold through its reseller agreements consist of the Company’s software subscriptions and products. Subscriptions sold through resellers are recognized on a straight-line basis over the period the underlying subscriptions are provided to the end customer. Products sold through resellers are shipped directly to the end customer and are recognized when title transfers to the end customer. Revenue from resellers has predominantly been recorded on a gross basis for all periods presented. The Company records reductions to revenue for estimated sales returns and customer credits at the time the related revenue is recognized. Sales returns and customer credits are estimated based on historical experience, current trends and expectations regarding future experience. Customer billings related to taxes imposed by and remitted to governmental authorities on revenue-producing transactions are reported on a net basis. When such remitted taxes exceed the amount billed to customers, the cost is included in general and administrative expenses. Amounts billed in excess of revenue recognized for the period are reported as deferred revenue on the consolidated balance sheet. The Company’s deferred revenue consists primarily of unearned revenue on annual and monthly subscription plans. The Company received one-time up-front payments for implementation services to be performed in connection with its carrier agreements with BT and TELUS during the year ended December 31, 2014. These amounts are being amortized on a straight-line basis over their respective initial contractual terms beginning in 2015. The BT and TELUS arrangements have initial contractual terms of three to five years, which approximates the estimated average customer life of each respective agreement. Accordingly, the portion of these one-time up-front payments that is estimated to be realized beyond December 31, 2016, or $1.1 million, is included as a component of other long-term liabilities in the consolidated balance sheets. Cost of Revenues Cost of software subscriptions revenue primarily consists of costs of network capacity purchased from third-party telecommunications providers, network operations, costs to equip and maintain data centers, including co-location fees for the right to place the Company’s servers in data centers owned by third-parties, depreciation of the servers and equipment, along with related utilities and maintenance costs. Cost of software subscriptions revenue also includes personnel costs associated with non-administrative customer care and support of the functionality of the Company’s platform and data center operations, including share-based compensation expenses and allocated costs of facilities and information technology. Cost of software subscriptions revenue is expensed as incurred. Cost of product revenue is comprised primarily of the cost associated with purchased phones, shipping costs, as well as personnel costs for contractors and allocated costs of facilities and information technology related to the procurement, management and shipment of phones. Cost of product revenue is expensed in the period product is delivered to the customer. Share-Based Compensation All share-based compensation resulting from options, restricted stock units (RSUs) and employee stock purchase plan rights granted to employees under our stock plans are measured as the grant date fair value of the award and recognized in the consolidated statements of operations over the requisite service period, which is generally the vesting period. The Company estimates the fair value of stock options and ESPP rights using the Black-Scholes-Merton option-pricing model. Compensation expense is recognized using the straight-line method net of estimated forfeitures. Share-based compensation expense resulting from stock options granted to non-employees is calculated using the Black-Scholes-Merton option-pricing model and RSUs value is measured as the grant date fair value of the award and is recognized in the consolidated statements of operations over the service period. Compensation expense for non-employee stock options and RSUs subject to vesting is revalued, or marked to market, as of each reporting date until the stock options and RSUs are vested. Research and Development Research and development expenses consist primarily of third-party contractor costs, personnel costs, technology license expenses, and depreciation associated with research and development equipment. Research and development costs are expensed as incurred. Internal-use software development costs that qualify for capitalization are amortized to cost of sales over the estimated useful life of the software. Advertising Costs Advertising costs, which include various forms of e-commerce such as search engine marketing, search engine optimization and online display advertising, as well as more traditional forms of media advertising such as radio and billboards, are expensed as incurred and were $34.3 million, $27.1 million, and $22.9 million for the years ended December 31, 2015, 2014 and 2013, respectively. Commissions Commissions consist of variable compensation earned by sales personnel and third-party resellers. Sales commissions associated with the acquisition of a new customer contract are recognized as sales and marketing expense at the time the customer has entered into a binding agreement. Income Taxes The Company accounts for income taxes using the asset and liability method. Deferred tax assets and liabilities are recognized for the estimated future tax consequences attributable to differences between the financial statement carrying amounts of existing assets and liabilities and their respective tax basis. Deferred tax assets and liabilities are measured using enacted tax rates in effect for the year in which those temporary differences are expected to be recovered or settled. The effect on deferred tax assets and liabilities of a change in tax rates is recognized in operations in the period that includes the enactment date. The Company records a valuation allowance to reduce its deferred tax assets to the amount of future tax benefit that is more likely than not to be realized. As of December 31, 2015, except for deferred tax assets associated with its subsidiaries in the Netherlands and China, the Company recorded a full valuation allowance against all other net deferred tax assets due to its history of operating losses. The Company classifies interest and penalties on unrecognized tax benefits as income tax expense. Segment Information The Company has determined the chief executive officer is the chief operating decision maker. The Company’s chief executive officer reviews financial information presented on a consolidated basis for purposes of assessing performance and making decisions on how to allocate resources. Accordingly, the Company has determined that it operates in a single reporting segment. Indemnification Certain of the Company’s agreements with resellers and customers include provisions for indemnification against liabilities if its subscriptions infringe a third-party’s intellectual property rights. At least quarterly, the Company assesses the status of any significant matters and its potential financial statement exposure. If the potential loss from any claim or legal proceeding is considered probable and the amount or the range of loss can be estimated, the Company accrues a liability for the estimated loss. The Company has not incurred any material costs as a result of such indemnification provisions and the Company has not accrued any liabilities related to such obligations in the consolidated financial statements as of December 31, 2015 or 2014. Recent Accounting Pronouncements In May 2014, the Financial Accounting Standards Board (the “FASB”) issued Accounting Standards Update (ASU) No. 2014-09, Revenue from Contracts with Customers (Topic 606) In September 2015, the FASB issued ASU No. 2015-16, Business Combinations (Topic 805): Simplifying the Accounting for Measurement-Period Adjustments In November 2015, the FASB issued ASU No. 2015-17, Balance Sheet Classification of Deferred Taxes In February 2016, the FASB issued ASU 2016-02, Leases

Financial Statement Components

Financial Statement Components	12 Months Ended
	Dec. 31, 2015
Organization Consolidation And Presentation Of Financial Statements [Abstract]
Financial Statement Components	Note 2. Financial Statement Components Cash and cash equivalents consisted of the following (in thousands): December 31, December 31, 2015 2014 Cash $ 18,422 $ 12,800 Money market funds 119,166 100,382 Total cash and cash equivalents $ 137,588 $ 113,182 Accounts receivable, net consisted of the following (in thousands): December 31, December 31, 2015 2014 Accounts receivable $ 15,509 $ 5,935 Unbilled accounts receivable 4,031 1,841 Allowance for doubtful accounts (377 ) (125 ) Accounts receivable, net $ 19,163 $ 7,651 Property and equipment, net consisted of the following (in thousands): December 31, December 31, 2015 2014 Computer hardware and software $ 49,774 $ 43,805 Internal-use software development costs 7,432 5,335 Furniture and fixtures 3,610 2,020 Leasehold improvements 2,412 2,870 Property and equipment, gross 63,228 54,030 Less: accumulated depreciation and amortization (35,068 ) (28,503 ) Property and equipment, net $ 28,160 $ 25,527 Total depreciation and amortization expense was $13.5 million, $10.4, and $9.0 million for the fiscal years ended December 31, 2015, 2014 and 2013, respectively. Accrued liabilities consisted of the following (in thousands): December 31, December 31, 2015 2014 Accrued compensation and benefits $ 10,128 $ 7,596 Accrued sales, use and telecom related taxes 5,243 5,277 Other accrued expenses 19,331 16,363 Total accrued liabilities $ 34,702 $ 29,236

Fair Value of Financial Instrum

Fair Value of Financial Instruments	12 Months Ended
	Dec. 31, 2015
Fair Value Disclosures [Abstract]
Fair Value of Financial Instruments	Note 3. Fair Value of Financial Instruments The Company carries certain financial assets consisting of money market funds and certificates of deposit at fair value on a recurring basis. Fair value is based on the price that would be received from selling an asset or paid to transfer a liability in an orderly transaction between market participants at the measurement date. Fair value is estimated by applying the following hierarchy, which prioritizes the inputs used to measure fair value into three levels and bases the categorization within the hierarchy upon the lowest level of input that is available and significant to the fair value measurement: Level 1: Observable inputs which include unadjusted quoted prices in active markets for identical assets or liabilities. Level 2: Observable inputs other than Level 1 inputs, such as quoted prices for similar assets or liabilities, quoted prices for identical or similar assets or liabilities in inactive markets, or other inputs that are observable or can be corroborated by observable market data for substantially the full term of the asset or liability. Level 3: Unobservable inputs that are supported by little or no market activity and that are based on management’s assumptions, including fair value measurements determined by using pricing models, discounted cash flow methodologies or similar valuation techniques. The financial assets carried at fair value were determined using the following inputs (in thousands): Balance at December 31, (Level 1) (Level 2) (Level 3) Cash equivalents: Money market funds $ 119,166 $ 119,066 $ 100 $ — Other assets: Certificates of deposit $ 530 $ — $ 530 $ — Balance at December 31, (Level 1) (Level 2) (Level 3) Cash equivalents: Money market funds $ 100,570 $ 94,274 $ 6,296 $ — Short-term investments: Corporate debt securities $ 26,481 $ 26,481 $ — $ — Commercial paper $ 1,998 $ — $ 1,998 $ — Other assets: Certificates of deposit $ 630 $ — $ 630 $ — During the third quarter of 2014, the Company purchased investments in commercial paper and corporate debt securities with maturities ranging from 5 to 15 months. All investments matured during 2015. At December 31, 2014, all investments were designated as available-for-sale and reported at fair value based either upon quoted prices in active markets, quoted prices in less active markets, or quoted market prices for similar investments, with unrealized gains and losses, net of related tax, if any, included in other comprehensive loss. At December 31, 2014, available-for-sale securities consisted of the following (in thousands): Available-for-Sale Securities Amortized Cost Gross Unrealized Gains Gross Unrealized Losses Estimated Fair Value Corporate debt securities $ 26,700 $ 45 $ (264 ) $ 26,481 Commercial paper 1,996 2 — 1,998 Total $ 28,696 $ 47 $ (264 ) $ 28,479 The expected maturities of our investments in available-for-sale securities at December 31, 2014 are shown below (in thousands): Available-for-Sale Securities Amortized Cost Estimated Fair Value Due in less than one year $ 28,696 $ 28,479 Total $ 28,696 $ 28,479 The At December 31, 2015 and 2014, the Company estimated the fair value of its debt primarily using an expected present value technique, which is based on observable market inputs using interest rates currently available to companies of similar credit standing for similar terms and remaining maturities, and considering its own credit risk. The estimated fair value of the Company’s current and non-current debt obligations was $19.0 million at December 31, 2015, compared to its carrying amount of $18.6 million at that date. The estimated fair value of the Company’s current and non-current debt obligations was $25.7 million at December 31, 2014, compared to its carrying amount of $24.6 million at that date. If the debt was measured at fair value in th e consolidated balance sheets, the Company’s current and non-current debt would be classified in Level 2 of the fair value hierarchy.

Business Combinations

Business Combinations	12 Months Ended
	Dec. 31, 2015
Business Combinations [Abstract]
Business Combinations	Note 4. Business Combinations On June 4, 2015, the Company acquired Glip, Inc., or Glip, a cloud messaging and collaboration company based in Boca Raton, Florida. Glip is a provider of team messaging services, integrated with project management, group calendars, notes, annotations, and file sharing. Glip also includes integrations with a number of third party business solutions. The objective of the acquisition is to extend our platform by adding team messaging and collaboration services such as calendar, project management, and document sharing. The consideration for this acquisition, net of cash acquired and including the fair value of contingent consideration payable in cash upon achievement of certain earn out milestones and the fair value of common stock issuable to the sellers was $11.9 million. Under the terms of the acquisition, the Company may also pay up to $2.0 million in payments at the end of a two-year period to certain Glip employees, who continue to be employees of the Company, which are accounted for as a post-combination expense. At December 31, 2015, the contingent payment liability is $0.6 million and classified as a non-current liability in the consolidated balance sheets. The consideration exchanged consisted of the following (in thousands): Cash, net of cash acquired $ 4,670 Common stock issued (223,190 shares) 3,447 Holdback based on standard representations and warranties 1,500 Total initial consideration 9,617 Milestone based earn out (after valuation adjustment) 2,289 Total consideration $ 11,906 The $3.5 million fair value of the 223,190 unregistered common shares issued as part of the consideration paid for Glip ($3.8 million before a $0.4 million discount due to a 6-month restriction of resale as a result of SEC Rule 144 for issuance of unregistered shares) was determined on the basis of the five day weighted closing market price of the Company’s common shares preceding the acquisition date. We determined the initial fair value of the milestone based earn out liability of $2.3 million using various estimates, including probabilities of success and discount rates. The following table summarizes the fair value of assets acquired as of the date of acquisition (in thousands): Cash and cash equivalents $ 74 Acquired intangible assets 3,850 Goodwill 7,982 Net assets acquired $ 11,906 The Company has included the financial results of Glip, which were not material, in the consolidated statements of operations from the date of acquisition. The goodwill balance is primarily attributed to the assembled workforce and expanded market opportunities when integrating Glip’s cloud messaging and collaboration technology with the Company’s other offerings. The goodwill balance is not deductible for U.S. income tax purposes. The following table sets forth the fair value components of identifiable acquired intangible assets (in thousands) and their estimated useful lives (in years) as of the date of acquisition: Fair Value Estimated Useful Life Customer relationships $ 840 2 years Developed technology 3,010 5 years Total identifiable acquired intangible assets subject to amortization $ 3,850 The amount recorded for developed technology represents the estimated fair value of Glip’s cloud messaging and collaboration technology. The amount recorded for customer relationships represents the fair values of the underlying relationships with Glip customers. The weighted-average amortization periods for customer relationships and developed technology are approximately 1.4 years and 4.4 years, respectively. Acquired intangible assets as of December 31, 2015 were as follows (in thousands): Gross Carrying Amount Accumulated Amortization Acquired Intangibles, Net Customer relationships $ 840 $ 240 $ 600 Developed technology 3,010 344 2,666 Total acquired intangible assets $ 3,850 $ 584 $ 3,266 Amortization expense from acquired intangible assets for the year ended December 31, 2015 was $0.6 million. Amortization of developed technology is included in research and development expenses and amortization of customer relationships is included in sales and marketing expenses in the consolidated statements of operations. Estimated amortization expense for acquired intangible assets for the following five fiscal years and thereafter is as follows (in thousands): 2016 $ 1,022 2017 782 2018 602 2019 602 2020 258 Total estimated amortization expense $ 3,266

Debt

Debt	12 Months Ended
	Dec. 31, 2015
Debt Disclosure [Abstract]
Debt	Note 5. Debt As of December 31, 2015, the Company’s debt is comprised of borrowings under the Third Amended and Restated Loan and Security Agreement dated March 30, 2015 (the “SVB Agreement”), as amended, with Silicon Valley Bank, or SVB. Silicon Valley Bank Credit Facility Under the SVB agreement, the Company has one outstanding growth capital term loan (i.e., “the 2013 term loan”) and a revolving line of credit. The Company borrowed an additional growth capital loan in March 2012 (the “2012 term loan”) that matured in March 2015 and was repaid in full. The 2012 term loan was borrowed in March 2012 with a principal amount of $8.0 million, which was repaid in 36 equal monthly installments of principal and interest. Under the 2012 term loan, interest was paid monthly and accrued at a floating rate based on the Company’s option of the (i) prime rate plus a margin of 0.25% or 0.50% or (ii) adjusted LIBOR rate (based on one, two, three or six-month interest periods) plus a margin of 3.25% or 3.50%, in each case such margin was determined based on cash balances maintained with SVB. The Company elected the prime rate option and, based on cash balances maintained with SVB, the interest rate was 3.50%. In addition, a final terminal payment equal to 0.5% of the original loan principal, or $40,000, was due at maturity. The 2012 term loan matured in March 2015 and was repaid in full. The 2013 term loan was borrowed on December 31, 2013 with a principal amount of $15.0 million, which is being repaid in 48 equal monthly installments of principal and interest. Interest is due monthly and accrues at a floating rate based on the Company’s option of an annual rate of either the (i) prime rate plus a margin of 0.75% or 1.00% or (ii) adjusted LIBOR rate (based on one, two, three or six-month interest periods) plus a margin of 3.75% or 4.00%, in each case such margin being determined based on cash balances maintained with SVB. The Company elected the prime rate option and based on cash balances maintained with SVB at December 31, 2015, the current interest rate is 4.00%. As of December 31, 2015, the outstanding principal balance of the 2013 term loan was $7.8 million. Approximately $4.1 million of the remaining principal balance is classified as non-current liabilities in the accompanying consolidated balance sheet as this portion of the remaining principal balance is due beyond December 31, 2016. The revolving line of credit provides for a maximum borrowing of up to $15.0 million subject to limits based on the outstanding principal balance of the 2012 term loan and recurring software subscription revenue amounts as defined in the agreement. The recurring software subscription revenue requirement is not expected to limit the amount of borrowings available under the line of credit. Under the line of credit, interest is paid monthly and accrues at a floating rate based on the Company’s option of the (i) prime rate plus a margin of 0.25% or 0.50% or (ii) adjusted LIBOR rate (based on one, two, three or six-month interest periods) plus a margin of 3.25% or 3.50%, in each case such margin being determined based on cash balances maintained with SVB. The Company elected the prime rate option and based on cash balances maintained with SVB at December 31, 2015, the current interest rate is 3.50%. On August 11, 2015, the Company amended the terms of the SVB Agreement extending the maturity of the revolving line of credit from August 13, 2015 to August 14, 2017. The outstanding principal balance is classified as non-current liabilities in the accompanying consolidated balance sheet as the principal balance is due beyond December 31, 2016. As of December 31, 2015, the outstanding principal balance and the available borrowing capacity of the line of credit were $10.8 million and $4.2 million, respectively. The Company has pledged all of its assets, excluding intellectual property, as collateral to secure its obligations under the SVB agreement. The SVB agreement contains customary negative covenants that limit the Company’s ability to, among other things, incur additional indebtedness, grant liens, make investments, repurchase stock, pay dividends, transfer assets and merge or consolidate. The SVB agreement also contains customary affirmative covenants, including requirements to, among other things, (i) maintain minimum cash balances representing the greater of $10.0 million or three times the Company’s quarterly cash burn rate, as defined in the agreement, and (ii) maintain minimum EBITDA levels, as determined in accordance with the agreement. On March 30, 2015, the Company adjusted certain financial covenant thresholds to expand its ability to invest in certain foreign subsidiaries and property and equipment. The Company was in compliance with all covenants under its credit agreement with SVB as of December 31, 2015. TriplePoint Capital Credit Facility Under the equipment loan and security agreement with TriplePoint, the Company borrowed equipment term loans with aggregate principal of $9.7 million in August 2012. The equipment term loans were being repaid in 36 equal monthly installments of principal and interest, which accrued at an annual fixed rate of 5.75% however, the Company repaid the equipment term loans in full in March 2015. In addition, a final terminal payment was due at maturity equal to 10% of the original loan principal, or $1.0 million. The Company’s outstanding balances under its debt agreements as of December 31, 2015 and 2014 were as follows (in thousands): December 31, 2015 2014 SVB loan and security agreement $ 18,590 $ 23,008 TriplePoint equipment loan agreement — 1,725 18,590 24,733 Loan discounts — (156 ) Net carrying value of debt $ 18,590 $ 24,577 Less: Current portion of long-term debt (3,750 ) (16,764 ) Long-term debt $ 14,840 $ 7,813 As of December 31, 2015, future debt principal payments are scheduled as follows (in thousands): Year ending December 31, 2016 $ 3,750 2017 14,527 2018 313 $ 18,590

Commitments and Contingencies

Commitments and Contingencies	12 Months Ended
	Dec. 31, 2015
Commitments And Contingencies Disclosure [Abstract]
Commitments and Contingencies	Note 6. Commitments and Contingencies Leases The Company leases facilities for office space under non-cancelable operating leases for its U.S. and international locations and has entered into capital lease arrangements to obtain property and equipment for its operations. In addition, the Company leases space from third party datacenter hosting facilities under co-location agreements to support its cloud infrastructure. As of December 31, 2015, non-cancelable leases expire on various dates between 2016 and 2021 and require the following future minimum lease payments by year (in thousands): Capital Leases Operating Leases Year ending December 31, 2016 $ 301 $ 5,383 2017 185 5,080 2018 — 4,922 2019 — 4,243 2020 — 3,449 2021 — 2,072 Total future minimum lease payments 486 $ 25,149 Less: amount representing interest (36 ) Total capital lease obligation 450 Less: Current portion of capital lease obligation (269 ) Capital lease obligation $ 181 Property and equipment recorded under capital leases consisted of the following (in thousands): December 31, 2015 2014 Property and equipment acquired under capital lease $ 3,149 $ 3,466 Less: accumulated amortization (2,212 ) (2,129 ) Property and equipment acquired under capital lease, net $ 937 $ 1,337 Operating leases for certain office facilities include scheduled periods of abatement and escalation of rental payments. The Company recognizes rent expense on a straight-line basis for all operating lease arrangements with the difference between required lease payments and rent expense recorded as deferred rent. Total rent expense was $4.0 million, $2.2 million, and $1.3 million for the fiscal years ended December 31, 2015, 2014 and 2013, respectively. Sales Tax Liability During 2010 and 2011, the Company increased its sales and marketing activities in the U.S., which may be asserted by a number of states to create an obligation under nexus regulations to collect sales taxes on sales to customers in the state. Prior to 2012, the Company did not collect sales taxes from customers on sales in all states. In the second quarter of 2012, the Company commenced collecting and remitting sales taxes on sales in all states, therefore the loss contingency is applicable to sales and marketing activities in 2010, 2011 and the three months ended March 31, 2012. As of December 31, 2015 and 2014, the Company recorded a long-term sales tax liability of $3.7 million, and $4.0 million, respectively, based on its best estimate of the probable liability for the loss contingency incurred as of those dates. The Company’s estimate of a probable outcome under the loss contingency is based on analysis of its sales and marketing activities, revenues subject to sales tax, and applicable regulations in each state in each period. No significant adjustments to the long-term sales tax liability have been recognized in the accompanying consolidated financial statements for changes to the assumptions underlying the estimate. However, changes in management’s assumptions may occur in the future as the Company obtains new information which can result in adjustments to the recorded liability. Increases and decreases to the long-term sales tax liability are recorded as general and administrative expense. A current sales tax liability for non-contingent amounts expected to be remitted in the next 12 months of $4.4 million and $4.2 million is included in accrued liabilities as of December 31, 2015 and 2014, respectively. Legal Matters The Company determines whether an estimated loss from a contingency should be accrued by assessing whether a loss is deemed probable and can be reasonably estimated. The Company assesses its potential liability by analyzing specific litigation and regulatory matters using reasonably available information. The Company develops its views on estimated losses in consultation with inside and outside counsel, which involves a subjective analysis of potential results and outcomes, assuming various combinations of appropriate litigation and settlement strategies. Legal fees are expensed in the period in which they are incurred. As of December 31, 2015 and 2014, there were no significant ongoing legal matters and the Company did not have any accrued liabilities recorded for such loss contingencies. Employee Agreements The Company has signed various employment agreements with executives and key employees pursuant to which if the Company terminates their employment without cause or if the employee does so for good reason following a change of control of the Company, the employees are entitled to receive certain benefits, including severance payments, accelerated vesting of stock options and RSUs and continued COBRA coverage. As of December 31, 2015, no triggering events which would cause these provisions to become effective have occurred. Therefore, no liabilities have been recorded for these agreements in the consolidated financial statements.

Stockholders' Equity

Stockholders' Equity	12 Months Ended
	Dec. 31, 2015
Equity [Abstract]
Stockholders' Equity	Note 7. Stockholders’ Equity In connection with the Company’s initial public offering (IPO), the Company reincorporated in Delaware on September 26, 2013. The Delaware certificate of incorporation provides for two classes of common stock: Class A and Class B common stock, both with a par value of $0.0001 per share. In addition the certificate of incorporation authorizes shares of undesignated preferred stock with a par value of $0.0001 per share. The terms of preferred stock are described below. Preferred Stock The Board of Directors may, without further action by the stockholders, fix the rights, preferences, privileges and restrictions of up to an aggregate of 100,000,000 shares of preferred stock in one or more series and authorizes their issuance. These rights, preferences, and privileges could include dividend rights, conversion rights, voting rights, terms of redemption, liquidation preferences, sinking fund terms and the number of shares constituting any series or the designation of such series, any or all of which may be greater than the rights of the Class A and Class B common stock. As of December 31, 2015 and 2014, there were 100,000,000 shares of preferred stock authorized and no shares issued or outstanding. Class A and Class B Common Stock The Company has authorized 1,000,000,000 and 250,000,000 shares of Class A common stock and Class B common stock for issuance. Holders of our Class A common stock and Class B common stock have identical rights for matters submitted to a vote of our stockholders. Holders of Class A common stock are entitled to one vote per share of Class A common stock and holders of Class B common stock are entitled to 10 votes per share of Class B common stock. Holders of shares of Class A common stock and Class B common stock vote together as a single class on all matters (including the election of directors) except for specific circumstances that would adversely affect the powers, preferences or rights of a particular class of common stock. Subject to preferences that may apply to any shares of preferred stock outstanding at the time, holders of Class A and Class B common stock share equally, identically and ratably, on a per share basis, with respect to any dividend or distribution of cash, property or shares of the Company’s capital stock. Holders of Class A and Class B common stock also share equally, identically and ratably in all assets remaining after the payment of any liabilities and liquidation preferences and any accrued or declared but unpaid dividends, if any, with respect to any outstanding preferred stock at the time. Each share of Class B common stock is convertible at any time at the option of the holder into one share of Class A common stock. In addition, each share of Class B common stock will convert automatically to Class A common stock upon: (i) the date specified by an affirmative vote or written consent of holders of at least 67% of the outstanding shares of Class B common stock, or (ii) the seven year anniversary of the closing date of the IPO (October 2, 2020). Shares of Class A common stock reserved for future issuance were as follows (in thousands): December 31, 2015 Preferred stock 100,000 Class B common stock 13,483 2013 Employee stock purchase plan 1,899 2013 Equity incentive plan: Outstanding options and restricted stock unit awards 10,337 Available for future grants 7,764 133,483 As of December 31, 2015 and 2014, there were 2,330 and 14,893 shares of common stock outstanding related to the early exercise of non-vested options subject to repurchase at the original exercise price by the Company upon termination of service by an employee.

Share-Based Compensation

Share-Based Compensation	12 Months Ended
	Dec. 31, 2015
Disclosure Of Compensation Related Costs Sharebased Payments [Abstract]
Share-Based Compensation	Note 8. Share-Based Compensation A summary of share-based compensation expense recognized in the Company’s consolidated statements of operations follows (in thousands): Year Ended December, 31 2015 2014 2013 Cost of software subscriptions revenue $ 2,054 $ 1,294 $ 539 Research and development 5,387 3,343 1,495 Sales and marketing 7,200 5,260 1,313 General and administrative 7,447 5,619 4,193 Total share-based compensation expense $ 22,088 $ 15,516 $ 7,540 A summary of share-based compensation expense by award type follows (in thousands): Year Ended December, 31 2015 2014 2013 Options $ 11,170 $ 10,323 $ 7,069 Employee stock purchase plan rights 1,365 1,628 453 Restricted stock units 9,553 3,565 18 Total share-based compensation expense $ 22,088 $ 15,516 $ 7,540 Equity Incentive Plans In September 2013, the Board adopted and the Company’s stockholders approved the 2013 Equity Incentive Plan (the “2013 Plan”). The 2013 Plan became effective on September 26, 2013. In connection with the adoption of the 2013 Plan, the Company terminated the 2010 Equity Incentive Plan (the “2010 Plan”), under which stock options had been granted prior to September 26, 2013. The 2010 Plan was established in September 2010, when the 2003 Equity Incentive Plan (the “2003 Plan”) was terminated. After the termination of the 2003 and 2010 Plans, no additional options were granted under these plans; however options previously granted will continue to be governed by these plans, and will be exercisable into shares of Class B common stock. In addition, options authorized to be granted under the 2003 and 2010 Plans, including forfeitures of previously granted awards are authorized for grant under the 2013 Plan. A total of 6,200,000 shares of Class A common stock have been reserved for issuance under the 2013 Plan. The 2013 Plan includes an annual increase on the first day of each fiscal year beginning in 2014, equal to the least of: (i) 6,200,000 shares of Class A common stock; (ii) 5% of the outstanding shares of all classes of common stock as of the last day of the Company’s immediately preceding fiscal year; or (iii) such other amount as the board of directors may determine. During the year ended December 31, 2015, a total of 3,427,922 shares of Class A common stock were added to the 2013 Plan in connection with the annual automatic increase provision. The plans permit the grant of stock options and other share-based awards, such as restricted stock units to employees, officers, directors and consultants by the Company’s board of directors. Option awards are generally granted with an exercise price equal to the fair market value of the Company’s common stock at the date of grant. Option awards generally vest according to a graded vesting schedule based on four years of continuous service. On January 29, 2014, the Compensation Committee of the Board of Directors approved an amendment to decrease the contractual term of all equity awards issued from the 2013 Plan from 10 years to 7 years for all awards granted after January 29, 2014. A summary of option activity under all of the plans at December 31, 2015 and changes during the periods then ended is presented in the following table: Weighted- Number of Weighted- Average Aggregate Options Average Contractual Intrinsic Outstanding Exercise Price Term Value (in thousands) Per Share (in Years) (in thousands) Outstanding at December 31, 2012 8,609 $ 2.89 7.2 $ 40,705 Granted 3,856 11.54 Exercised (607 ) 1.47 Canceled/Forfeited (702 ) 4.31 Outstanding at December 31, 2013 11,156 $ 5.87 7.7 $ 139,484 Granted 1,302 15.12 Exercised (2,673 ) 1.97 Canceled/Forfeited (627 ) 7.19 Outstanding at December 31, 2014 9,158 $ 8.23 7.2 $ 61,367 Granted 1,881 16.35 Exercised (2,323 ) 6.82 Canceled/Forfeited (668 ) 11.42 Outstanding at December 31, 2015 8,048 $ 10.27 6.2 $ 107,091 Vested and expected to vest as of December 31, 2015 7,972 $ 10.26 6.2 $ 106,197 Exercisable as of December 31, 2015 4,750 $ 7.40 6.0 $ 76,843 The total intrinsic values of options exercised were as follows (in thousands): Year Ended December 31, 2015 2014 2013 Total intrinsic value of options exercised $ 28,336 $ 41,454 $ 10,261 Valuation Assumptions The Company estimated the fair values of each option awarded on the date of grant using the Black-Scholes-Merton option-pricing model, which requires inputs including the fair value of common stock, expected term, expected volatility, risk-free interest and dividend yield. Fair Value of Common Stock Given the absence of a public trading market prior to the September 23, 2013 IPO, the Company’s board of directors considered numerous objective and subjective factors to determine the fair value of common stock at each meeting at which awards were approved. These factors included, but were not limited to: (i) contemporaneous valuations of common stock performed by an unrelated valuation specialist; (ii) developments in the Company’s business and stage of development; (iii) the Company’s operational and financial performance and condition; (iv) issuances of preferred stock and the rights and preferences of preferred stock relative to common stock; (v) current condition of capital markets and the likelihood of achieving a liquidity event, such as an initial public offering or sale of the Company; and (vi) the lack of marketability of common stock. For financial reporting purposes, the Company also considered contemporaneous valuations of common stock prepared for dates subsequent to the grant date. For certain option grants in 2012 and 2013 that occurred on an interim date between valuation dates, the fair value of common stock used in the option-pricing model to measure share-based compensation for the period exceeded the exercise price. Since the IPO, the Company has used the daily adjusted closing stock price on the New York Stock Exchange on the date of grant as the fair value of the common stock. Expected Term The expected term represents the period that share-based awards are expected to be outstanding. Prior to the fourth quarter of 2014, the Company did not have sufficient historical information to develop reasonable expectations about future exercise behavior, the expected term for options issued to employees was calculated as the mean of the option vesting period and the contractual term (i.e., the “Simplified Method”). Beginning the fourth quarter of 2014, the Company began incorporating its own historical data, assigning a 25% weighting to the Company’s historical data and a 75% weighting to the Simplified Method estimate. In the fourth quarter of 2015, 50% of the Company’s historical data was weighted with 50% of the Simplified Method. The expected term for options issued to non-employees was the contractual term. Expected Volatility The expected stock price volatility of common stock was derived from the historical volatilities of a peer group of similar publicly traded companies over a period that approximates the expected term of the option. Beginning the fourth quarter of 2014, the Company incorporated its own historical volatility assigning a 25% weighting to the Company’s historical data and a 75% weighting to the historical volatilities of a peer group of similarly traded companies. In the fourth quarter of 2015, 50% of the Company’s historical volatility was weighted with 50% of the Company’s peer group volatilities. Risk-Free Interest Rate The risk-free interest rate was based on the yield available on U.S. Treasury zero-coupon issues with a term that approximates the expected term of the option. Expected Dividend Yield The expected dividend yield was 0% as the Company has not declared, nor paid, and does not expect to pay, cash dividends. The weighted-average assumptions used in the option-pricing models and the resulting grant date fair value of stock options granted in the periods presented were as follows: Year ended December 31, 2015 2014 2013 Expected term for employees (in years) 4.8 4.6 6.1 Expected term for non-employees (in years) 7.0 7.0 10.0 Expected volatility 48 % 48 % 54 % Risk-free interest rate 1.22 % 1.41 % 1.68 % Expected dividend yield 0 % 0 % 0 % Grant date fair value of employee options $ 6.78 $ 6.16 $ 6.19 As of December 31, 2015 and 2014, there was approximately $19.6 million and $20.1 million of unrecognized share-based compensation expense, net of estimated forfeitures, related to stock option grants, which will be recognized on a straight-line basis over the remaining weighted-average vesting periods of approximately 2.5 years and 2.4 years, respectively. Employee Stock Purchase Plan The Employee Stock Purchase Plan (ESPP) allows eligible employees to purchase the Class A common stock at a discount through payroll deductions of up to the lesser of 15% of their eligible compensation or the IRS allowable limit per calendar year. A participant may purchase a maximum of 3,000 shares during an offering period. The offering period generally starts on the first trading day on or after May 11th and November 11th of each year. At the end of the offering period, the purchase price is set at the lower of: (i) 90% of the fair value of the Company’s common stock at the beginning of the six month offering period, and (ii) 90% of the fair value of the Company’s common stock at the end of the six month offering period. The ESPP provides for annual increases in the number of shares available for issuance under the ESPP on the first day of each fiscal year beginning in fiscal 2014, equal to the least of: (i) 1% of the outstanding shares of all classes of common stock on the last day of the immediately preceding year; (ii) 1,250,000 shares; or (iii) such other amount as may be determined by the board of directors. During the year ended December 31, 2015, a total of 685,584 shares of Class A common stock were added to the 2013 ESPP Plan in connection with the annual increase provision. At December 31, 2015, a total of 1,898,792 shares were available for issuance under the ESPP. The weighted-average assumptions used to value ESPP rights under the Black-Scholes-Merton option-pricing model and the resulting offering grant date fair value of ESPP rights granted in the periods presented were as follows: Year ended December 31, 2015 2014 Expected term (in years) 0.5 0.5 Expected volatility 42 % 50 % Risk-free interest rate 0.25 % 0.07 % Expected dividend yield 0 % 0 % Offering grant date fair value of ESPP rights $ 5.05 $ 3.93 As of December 31, 2015 and 2014, there was approximately $1.1 million and $0.4 million of unrecognized share-based compensation expense related to outstanding ESPP rights, which will be recognized on a straight-line basis over the remaining weighted average vesting period of approximately 0.4 and 0.4 years, respectively. Restricted Stock Units The 2013 Plan provides for the issuance of restricted stock units (RSUs) to employees and consultants. RSUs issued under the 2013 Plan generally vest over four years. A summary of activity of RSUs under the 2013 Plan at December 31, 2015 and changes during the periods then ended is presented in the following table: Number of Weighted- Aggregate RSUs Average Intrinsic Outstanding Grant Date Fair Value (in thousands) Value Per Share (in thousands) Outstanding at December 31, 2013 68 $ 17.22 $ 1,251 Granted 1,915 15.08 Released (110 ) 16.82 Canceled/Forfeited (134 ) 17.43 Outstanding at December 31, 2014 1,739 $ 14.87 $ 25,617 Granted 1,365 18.09 Released (571 ) 15.45 Canceled/Forfeited (245 ) 15.10 Outstanding at December 31, 2015 2,288 $ 16.63 $ 53,972 As of December 31, 2015 and 2014, there was a total of $35.2 million and $24.2 million of unrecognized share-based compensation expense, net of estimated forfeitures, related to RSUs, which will be recognized on a straight-line basis over the remaining weighted-average vesting period of approximately 3.0 years and 3.6 years, respectively.

Income Taxes

Income Taxes	12 Months Ended
	Dec. 31, 2015
Income Tax Disclosure [Abstract]
Income Taxes	Note 9. Income Taxes The provision (benefit) for income taxes consisted of the following (in thousands): Year ended December 31, 2015 2014 2013 Current: Federal $ — $ — $ — State 71 18 3 Foreign 85 114 (32 ) Total current 156 132 (29 ) Deferred: Federal $ (1,312 ) $ — $ — State (99 ) — — Foreign (8 ) (35 ) (16 ) Total deferred (1,419 ) (35 ) (16 ) Total income tax provision (benefit) $ (1,263 ) $ 97 $ (45 ) Net loss before provision (benefit) for income taxes consisted of the following (in thousands): Year ended December 31, 2015 2014 2013 United States $ (28,870 ) $ (50,065 ) $ (41,778 ) International (4,492 ) 1,822 (4,365 ) Total net loss before benefit for income taxes $ (33,362 ) $ (48,243 ) $ (46,143 ) The provision (benefit) for income tax differed from the amounts computed by applying the U.S. federal income tax rate of 34% to pretax loss as a result of the following (in thousands): Year ended December 31, 2015 2014 2013 Federal tax benefit at statutory rate $ (11,343 ) $ (16,403 ) $ (15,687 ) State tax, net of federal provision (benefit) (34 ) 12 2 Research and development credits (667 ) (654 ) (774 ) Share-based compensation 1,086 1,836 641 Other permanent differences 325 211 294 Foreign tax rate differential (80 ) (33 ) (20 ) Net operating losses not recognized 10,762 15,128 15,499 Release of valuation allowance associated with acquisitions (1,312 ) — — Total income tax provision (benefit) $ (1,263 ) $ 97 $ (45 ) The benefit for income taxes for 2015 relates primarily to the release of a valuation allowance of $1.4 million associated with nondeductible intangible assets recorded as part of the Glip acquisition, partially offset by state minimum income tax and income tax on our earnings in foreign jurisdictions. In connection with the acquisition of Glip, a deferred tax liability was established for the book/tax basis differences related to the non-goodwill intangible assets. The net deferred tax liability from this acquisition created an additional source of income to realize deferred tax assets. As the Company continues to maintain a full valuation allowance against its deferred tax assets, this additional source of income resulted in the release of the Company’s previously recorded valuation allowance against deferred assets. Consistent with the applicable guidance the release of the valuation allowance caused by the acquisition was recorded in the consolidated financial statements outside of acquisition accounting (i.e., recorded as a tax benefit to the consolidated statements of operations). In general, it is our practice and intention to reinvest the earnings of our non-U.S. subsidiaries in those operations. Undistributed earnings of foreign subsidiaries are immaterial for all periods presented. The types of temporary differences that give rise to significant portions of the Company’s deferred tax assets and liabilities are as follows (in thousands): Year ended December 31, 2015 2014 2013 Deferred tax assets Net operating loss and credit carry-forwards $ 54,858 $ 45,552 $ 35,904 Research and development credits 4,712 3,497 2,353 Sales tax liability 1,337 1,442 1,418 Share-based compensation 6,694 5,560 2,247 Accrued liabilities 6,090 4,676 2,528 Gross deferred tax assets 73,691 60,727 44,450 Valuation allowance (71,514 ) (60,405 ) (44,032 ) Total deferred tax assets 2,177 322 418 Deferred tax liabilities - Acquired intangibles (1,164 ) — — Deferred tax liabilities - Property and equipment (883 ) (197 ) (327 ) Net deferred tax assets $ 130 $ 125 $ 91 As a result of certain realization requirements of ASC 718, the table of deferred tax assets and liabilities does not include certain deferred tax assets as of December 31, 2015, 2014, and 2013, that arose directly from (or the use of which was postponed by) tax deductions related to equity compensation that are greater than the compensation recognized for financial reporting. Equity will be increased by $14.4 million if and when such deferred tax assets are ultimately realized. At December 31, 2015, the Company had net operating loss carry-forwards for federal and state income tax purposes of approximately $170.2 million and $117.0 million, respectively, available to reduce future income subject to income taxes. The federal and state net operating loss carry-forwards will begin to expire in 2023 and 2015, respectively. The Company also has research credit carry-forwards for federal and California tax purposes of approximately $3.6 million and $4.0 million, respectively, available to reduce future income subject to income taxes. The federal research credit carry-forwards will begin to expire in 2028 and the California research credits carry forward indefinitely. As of December 31, 2014, we had federal and state net operating loss carry-forwards of $140.1 million and $102.4 million, respectively, and federal and state research and development tax credit carry-forwards in the amount of $2.8 million and $2.8 million, respectively. The Internal Revenue Code of 1986, as amended, imposes restrictions on the utilization of net operating losses in the event of an “ownership change” of a corporation. Accordingly, a company’s ability to use net operating losses may be limited as prescribed under Internal Revenue Code Section 382 (IRC Section 382). Events which may cause limitations in the amount of the net operating losses that the Company may use in any one year include, but are not limited to, a cumulative ownership change of more than 50% over a three-year period. In the event the Company had subsequent changes in ownership, net operating losses and research and development credit carry-overs, which are reserved by the full deferred tax asset valuation allowance, could be limited and may expire unutilized. The Company’s management believes that, based on a number of factors, it is more likely than not, that all or some portion of the deferred tax assets will not be realized; and accordingly, for the year ended December 31, 2015, the Company has provided a valuation allowance against the Company’s U.S. and U.K. net deferred tax assets. The net change in the valuation allowance for the years ended December 31, 2015, 2014 and 2013 was an increase of $11.1 million, $16.4 million and $15.2 million, respectively. The Company has adopted the accounting policy that interest and penalties recognized are classified as part of its income taxes. The following shows the changes in the gross amount of unrecognized tax benefits as of December 31, 2015 (in thousands): Balance as of December 31, 2013 $ 933 Gross amount of increases in unrecognized tax benefits for tax positions taken in current year 465 Gross amount of increases in unrecognized tax benefits for tax positions taken in prior year 1,217 Balance as of December 31, 2014 $ 2,615 Gross amount of increases in unrecognized tax benefits for tax positions taken in current year 499 Gross amount of decreases in unrecognized tax benefits for tax positions taken in prior year (1,217 ) Balance as of December 31, 2015 $ 1,897 The Company does not anticipate that its total unrecognized tax benefits will significantly change due to settlement of examination or the expiration of statute of limitations during the next 12 months. The Company files U.S. and foreign income tax returns with varying statutes of limitations. Due to the Company’s net carry-over of unused operating losses, all years from 2003 forward remain subject to future examination by tax authorities.

Basic and Diluted Net Loss Per

Basic and Diluted Net Loss Per Share	12 Months Ended
	Dec. 31, 2015
Earnings Per Share [Abstract]
Basic and Diluted Net Loss Per Share	Note 10. Basic and Diluted Net Loss Per Share Basic net loss per share is computed by dividing the net loss by the weighted-average number of shares of common stock outstanding during the period, less the weighted-average unvested common stock subject to repurchase or forfeuiture as they are not deemed to be issued for accounting purposes. Diluted net loss per share is computed by giving effect to all potential shares of common stock, stock options, restricted stock units, ESPP, stock related to the non-vested early exercised stock options and stock related to non-vested restricted stock awards, to the extent dilutive. For the periods presented, all such common stock equivalents have been excluded from diluted net loss per share as the effect to net loss per share would be anti-dilutive. Year Ended December 31, 2015 2014 2013 Numerator Net loss $ (32,099 ) $ (48,340 ) $ (46,098 ) Denominator Weighted-average common shares for basic and diluted net loss per share 70,069 66,818 33,155 Basic and diluted net loss per share $ (0.46 ) $ (0.72 ) $ (1.39 ) Following is a table summarizing the potentially dilutive common shares that were excluded from diluted weighted-average common shares outstanding (in thousands): Year Ended December 31, 2015 2014 2013 Shares of common stock issuable upon conversion of warrants — — 502 Shares of common stock subject to repurchase 2 15 37 Shares of common stock issuable under equity incentive plans outstanding 10,337 10,897 11,224 Potential common shares excluded from diluted net loss per share 10,339 10,912 11,763

Geographic Concentrations

Geographic Concentrations	12 Months Ended
	Dec. 31, 2015
Risks And Uncertainties [Abstract]
Geographic Concentrations	Note 11. Geographic Concentrations Revenues by geographic location are based on the billing address of the customer. More than 90% of the Company’s revenues are from the United States for fiscal years ended December 31, 2015, 2014 and 2013. No other individual country exceeded 10% of total revenues for fiscal years ended December 31, 2015, 2014 and 2013. Property and equipment by geographic location is based on the location of the legal entity that owns the asset. At December 31, 2015 and 2014, more than 86% and 87% of the Company’s property and equipment is located in the United States, respectively. No other individual country exceeded 10% of total property and equipment at December 31, 2015 and 2014.

401 (k) Plan

401 (k) Plan	12 Months Ended
	Dec. 31, 2015
Compensation And Retirement Disclosure [Abstract]
401 (k) Plan	Note 12. 401(k) Plan The Company has a qualified defined contribution plan under Section 401(k) of the Internal Revenue Code covering eligible employees. The Company did not make any matching contributions to this plan in the periods presented.

Selected Quarterly Financial Da

Selected Quarterly Financial Data (Unaudited)	12 Months Ended
	Dec. 31, 2015
Quarterly Financial Information Disclosure [Abstract]
Selected Quarterly Financial Data (Unaudited)	Note 13. Selected Quarterly Financial Data (unaudited) The following tables set forth selected unaudited quarterly consolidated statements of operations data for each of the eight quarters in the years ended December 31, 2015 and 2014 (in thousands except per share data): Quarter ended Dec 31, Sept 30, 2015 June 30, 2015 Mar 31, 2015 Dec 31, 2014 Sept 30, 2014 June 30, 2014 Mar 31, 2014 Consolidated Statements of Operations Data: Revenues $ 83,439 $ 76,780 $ 70,691 $ 65,318 $ 61,893 $ 56,944 $ 52,787 $ 48,262 Gross profit 60,577 54,447 49,162 44,771 41,972 37,539 33,244 30,359 Operating loss (5,996 ) (5,828 ) (9,539 ) (9,569 ) (9,343 ) (10,814 ) (12,810 ) (12,238 ) Net Loss (6,941 ) (6,336 ) (8,211 ) (10,611 ) (10,120 ) (11,986 ) (13,330 ) (12,904 ) Net Loss per share, basic and diluted $ (0.10 ) $ (0.09 ) $ (0.12 ) $ (0.15 ) $ (0.15 ) $ (0.18 ) $ (0.20 ) $ (0.20 )

Related-Party Transactions

Related-Party Transactions	12 Months Ended
	Dec. 31, 2015
Related Party Transactions [Abstract]
Related-Party Transactions	Note 14. Related-Party Transactions During fiscal years 2015, 2014 and 2013, in the ordinary course of business, we purchased from Alphabet Inc. (the parent company of Google Inc.), an entity, for which one of our directors serves as a Vice President. Total payables to Alphabet at December 31, 2015 and 2014 were $2.0 million and $0.9 million, respectively. Total expenses incurred from Alphabet in 2015, 2014, and 2013 were $11.9 million, $10.1 million, and $10.7 million, respectively.

Subsequent Events

Subsequent Events	12 Months Ended
	Dec. 31, 2015
Subsequent Events [Abstract]
Subsequent Events	Note 15. Subsequent Events In January 2016, we signed an agreement with Westcon Group, Inc., or Westcon, a global distributor of communications devices with a global presence in 60 countries. The new agreement will leverage Westcon’s capabilities to configure, sell and support physical phone devices to our customers. We will continue to serve our customers who would like to buy phones by acting as an agent on behalf of Westcon. Responsibility for fulfillment of the obligation, inventory, accounts receivable, and warranty service will be transferred to Westcon. Once implemented, most of the revenue for physical phones will be with Westcon and will no longer be on our consolidated statements of operations. Instead, we will receive a commission from Westcon for our referral of sales to Westcon. We will replace the Product Revenue line on our consolidated statements of operations with a line called “Other Revenue”, which will mainly include commission revenue as an agent of Westcon, professional implementation services mainly for our larger customers, residual product revenue during the intermediary period of phasing the inventory to Westcon, and a small amount of product revenues coming from subsidized phones that we may occasionally offer, particularly in competitive bidding process.

Description of Business and S24

Description of Business and Summary of Significant Accounting Policies (Policies)	12 Months Ended
	Dec. 31, 2015
Organization Consolidation And Presentation Of Financial Statements [Abstract]
Public Offerings	Public Offerings On October 2, 2013, the Company completed an initial public offering (IPO) and sold 8,625,000 shares of Class A common stock to the public, including the underwriters’ overallotment option of 1,125,000 shares of Class A common stock and 80,000 shares of Class A common stock sold by selling stockholders, at a price of $13.00 per share. The offer and sale of all of the shares in the IPO were registered under the Securities Act pursuant to a registration statement on Form S-1 (File No. 333-190815) (the “Initial Registration Statement”). The Company received aggregate proceeds of $103.3 million from the IPO, net of underwriters’ discounts and commissions, but before deduction of offering expenses of approximately $3.9 million. On March 11, 2014, the Company completed a secondary public offering and sold 7,991,551 shares of Class A common stock to the public, including 791,551 of the underwriters’ overallotment option and 5,200,000 shares of Class A common stock sold by selling stockholders, at a price of $21.50 per share. The offer and sale of all of the shares in the secondary public offering were registered under the Securities Act pursuant to a registration statement on Form S-1 (File No. 333-194132) (Secondary Registration Statement). The Company received aggregate proceeds of $57.2 million from the secondary public offering, net of underwriters’ discounts and commissions, but before deduction of offering expenses of approximately $1.1 million. The Company did not receive any proceeds from the sale of shares by the selling stockholders.
Principles of Consolidation	Principles of Consolidation The accompanying consolidated financial statements have been prepared in accordance with U.S. generally accepted accounting principles (GAAP) and include the consolidated accounts of the Company and its wholly-owned subsidiaries. All intercompany accounts and transactions have been eliminated in consolidation.
Use of Estimates	Use of Estimates The preparation of financial statements in conformity with U.S. GAAP requires management 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 revenues and expenses during the reporting period. The significant estimates made by management affect revenues, accounts receivable, the allowance for doubtful accounts, inventory reserves, goodwill, share-based compensation, deferred revenue, return reserves, provision for income taxes, uncertain tax positions, loss contingencies, sales tax liabilities and accrued liabilities. Management periodically evaluates such estimates and they are adjusted prospectively based upon such periodic evaluation. Actual results could differ from those estimates.
Foreign Currency	Foreign Currency The functional currency of the Company’s foreign subsidiaries is generally the local currency. Adjustments resulting from translating foreign functional currency financial statements into U.S. dollars are recorded as part of a separate component of stockholders’ equity and reported in the statements of comprehensive loss. All assets and liabilities denominated in a foreign currency are translated into U.S. dollars at the exchange rate on the balance sheet date. Revenues and expenses are translated at the average exchange rate during the period. Foreign currency transaction gains and losses are included in other income (expense), net for the period.
Cash, Cash Equivalents and Investments in Marketable Securities	Cash, Cash Equivalents and Investments in Marketable Securities The Company considers highly liquid investments with a remaining maturity of three months or less at the date of purchase to be cash equivalents. The Company’s cash equivalents consist of money market funds. Cash equivalents are stated at cost plus accrued interest, which approximates fair value. Management determines the appropriate classification of its investments in marketable securities at the time of purchase and reevaluates such designation at each balance sheet date. At December 31, 2015, the Company’s cash equivalents consist of money market funds and it held no marketable securities. At December 31, 2014 the Company’s marketable securities consisted of investments in commercial paper and corporate debt securities. At December 31, 2014, all investments were designated as available-for-sale and reported at fair value based either upon quoted prices in active markets, quoted prices in less active markets, or quoted market prices for similar investments, with unrealized gains and losses, net of related tax, if any, included in accumulated other comprehensive loss in the consolidated balance sheet. These securities at any time can be liquidated for use in current operations or for other purposes, such as consideration for acquisitions, even if they had not yet reached maturity. As a result, all of our investments held at December 31, 2014 were classified as current assets in the accompanying consolidated balance sheet. The Company monitors its investments for potential impairment on a quarterly basis. When the carrying amount of an investment in any securities exceeds its fair value and the decline in value is determined to be other-than-temporary (i.e., when the Company does intend to sell the securities and it is more likely than not that the Company will be required to sell the securities prior to anticipated recovery of its amortized cost basis), management records an impairment charge to other income (expense), net, in the amount of the credit loss and the balance, if any, is recorded in accumulated other comprehensive loss in the consolidated balance sheets. No impairment losses have been recognized for the years ended December 31, 2015, 2014 and 2013.
Allowance for Doubtful Accounts	Allowance for Doubtful Accounts For the year ended December 31, 2013, a significant portion of revenues were realized from credit card transactions with only a small portion of revenues generating accounts receivable. For the years ended December 31, 2014 and 2015, the portion of revenues generating accounts receivable has increased as the Company’s larger customers are extended standard net 30 credit terms. For all periods presented, the Company has not experienced any significant defaults on its accounts receivable. The Company determines provisions based on historical experience and upon a specific review of customer receivables. Below is a summary of the changes in allowance for doubtful accounts for the years ended December 31, 2015, 2014 and 2013 (in thousands): Balance at Beginning of Period Provision, net of Recoveries Write-offs Balance at End of Period Year ended December 31, 2015 Allowance for doubtful accounts $ 125 $ 411 $ 159 $ 377 Year ended December 31, 2014 Allowance for doubtful accounts $ 139 $ 40 $ 54 $ 125 Year ended December 31, 2013 Allowance for doubtful accounts $ 433 $ (8 ) $ 286 $ 139
Inventory	Inventory The Company’s inventory consists primarily of telephones and peripheral equipment held at third parties. Inventory is stated at the lower of cost computed on a first-in, first-out basis, or market value. Inventory write-downs are recorded when the cost of inventory exceeds its net realizable value and establishes a new cost basis for the inventory. On a quarterly and annual basis, the Company analyzes inventory on a part by part basis in comparison to forecasted demand to identify potential excess and obsolescence issues, and adjusts carrying amounts to estimated net realizable value accordingly.
Internal-Use Software Development Costs	Internal-Use Software Development Costs The Company capitalizes qualifying internal-use software development costs that are incurred during the application development stage, provided that management with the relevant authority authorizes and commits to the funding of the project and it is probable the project will be completed and the software will be used to perform the function intended. Costs related to preliminary project activities and post implementation operation activities are expensed as incurred. Capitalized internal-use software development costs are included in property and equipment and are amortized on a straight-line basis to cost of revenues when the underlying project is ready for its intended use. In the fourth quarter of fiscal 2015, the Company determined that due to delays in the development and failure to achieve significant milestones by a third party supplier, certain software for internal use was no longer usable, and recorded a $1.3 million charge to the consolidated statements of operations. For the years ended December 31, 2015 and 2014, the Company capitalized $2.1 million and $0.7 million, net of impairment, of internal-use software development costs incurred, respectively. The carrying value of internal-use software development costs, net of amortization, was $2.6 million and $1.7 million at December 31, 2015 and 2014, respectively.
Property and Equipment, Net	Property and Equipment, Net Property and equipment, net is stated at cost, less accumulated depreciation and amortization, and is depreciated using the straight-line method over the estimated useful lives of the assets. Computer hardware and software, and furniture and fixtures are depreciated over useful lives ranging from three to five years; internal-use software development costs are amortized over useful lives ranging from three to four years; and leasehold improvements are depreciated over the respective lease term or useful life, whichever is shorter. Maintenance and repairs are charged to expense as incurred. The Company evaluates the recoverability of property and equipment for possible impairment whenever events or circumstances indicate that the carrying amount of such assets or asset groups may not be recoverable. Recoverability of these assets is measured by a comparison of the carrying amounts to the future undiscounted cash flows of the assets or asset groups are expected to generate. If such evaluation indicates that the carrying amount of the assets or asset groups is not recoverable, the carrying amount of such assets or asset groups is reduced to its estimated fair value. In the fourth quarter of fiscal 2015, the Company determined that due to delays in the development and failure to achieve significant milestones by a third party supplier, certain software for internal use was no longer usable, and recorded a $1.3 million charge to the consolidated statements of operations.
Concentrations	Concentrations Financial instruments that subject the Company to concentrations of credit risk consist primarily of cash, cash equivalents, investments in marketable securities, and accounts receivable. The Company maintains its cash, cash equivalent and investment balances, which may exceed federally insured limits, with financial institutions and corporate entities that complies with investment guidelines which management believes are financially sound and have minimal credit risk exposure. The Company’s accounts receivable are primarily derived from sales by resellers and to larger direct customers. The Company performs ongoing credit evaluations of its resellers and does not require collateral on accounts receivable. The Company maintains an allowance for doubtful accounts for estimated potential credit losses. At December 31, 2015 and 2014, AT&T, one of our resellers, accounted for 39% and 44% of the Company’s total accounts receivable, respectively. For the years ended December 31, 2015 and 2014, AT&T accounted for 13% and 12% of the Company’s total revenues and 12% and 11% of our software subscription revenues, respectively. For the year ended December 31, 2013, no single customer or reseller accounted for greater than 10% of the Company’s total revenues. The Company contracted a significant portion of its software development efforts from third-party vendors located in Russia and Ukraine during the years ended December 31, 2015, 2014 and 2013, respectively. A cessation of services provided by these vendors could result in a disruption to the Company’s research and development efforts.
Revenue Recognition	Revenue Recognition The Company’s revenues consist primarily of software subscriptions and product revenues. The Company’s software subscriptions revenue includes all fees billed in connection with subscriptions to the Company’s RingCentral Office, RingCentral Professional, RingCentral Fax, and RingCentral Contact Center SaaS applications. These software subscription fees include recurring fixed plan subscription fees, recurring administrative cost recovery fees, variable usage-based fees for blocks of additional minutes systematically purchased in advance of usage in excess of plan limits and one-time upfront fees. The Company provides its subscriptions pursuant to contractual arrangements that range in duration from one month to three years. The Company’s subscription fees are generally billed in advance directly to customer credit cards or via invoices issued to larger customers. The Company’s product revenue consists of sales of pre-configured office phones used in connection with the service and includes shipping and handling fees. The Company recognizes revenue when the following criteria are met: · there is persuasive evidence of an arrangement; · the subscription is being provided to the customer or the product has been delivered; · the collection of the fees is reasonably assured; and · the amount of fees to be paid by the customer is fixed or determinable. Revenue under subscription plans are recognized as follows: · fixed plan subscription and administrative cost recovery fees are recognized on a straight-line basis over their respective contractual subscription terms; · fees for additional minutes of usage in excess of plan limits are recognized over the estimated usage period in a manner that approximates actual usage; and · one-time upfront fees are initially deferred and recognized on a straight-line basis over the estimated average customer life. Product revenue is billed at the time the order is received and recognized when the product has been delivered to the customer. The Company enters into arrangements with multiple-elements that generally include services to be provided under the subscription plan and the sale of products used in connection with the Company’s subscriptions. The Company allocates the consideration to each deliverable in a multiple-deliverable arrangement based upon its relative selling prices. The Company determines the selling price using vendor-specific objective evidence (VSOE) for its subscription plans and best estimated selling price (BESP) for its product offerings. Consideration allocated to each deliverable, limited to the amount not contingent on future performance, are then recognized to revenue when the basic revenue recognition criteria are met for the respective deliverable. The Company determines VSOE based on historical standalone sales to customers. In determining VSOE, the Company requires that a substantial majority of the selling prices fall within a reasonably narrow pricing range. VSOE exists for all of the Company’s subscription plans. The Company uses BESP as the selling price for its product offerings as the Company is not able to determine VSOE of fair value from standalone sales or third-party evidence of selling price (TPE). The Company estimates BESP for a product by considering company-specific factors such as pricing objectives, direct product and other costs, bundling and discounting practices and contractually stated prices. A portion of the Company’s software subscriptions and product revenues are generated through sales by resellers. When the Company assumes a majority of the business risks associated with performance of the contractual obligations, it records these revenues at the gross amount paid by the customer with amounts retained by the resellers recognized as sales and marketing expense. The Company’s assumption of such business risks is evidenced when, among other things, it takes responsibility for delivery of the product or subscription, is involved in establishing pricing of the arrangement, assumes credit and inventory risk, and is the primary obligor in the arrangement. When a reseller assumes the majority of the business risks associated with the performance of the contractual obligations, the Company records the associated revenue at the net amount received from the reseller. The Company recognizes revenue from resellers when the following criteria are met: · persuasive evidence of an arrangement exists through a contract with the customer; · the subscription is being provided to the customer or the product has been delivered; · the amount of fees to be paid by the customer is fixed or determinable; and · the collection of the fees is reasonably assured. The Company’s deliverables sold through its reseller agreements consist of the Company’s software subscriptions and products. Subscriptions sold through resellers are recognized on a straight-line basis over the period the underlying subscriptions are provided to the end customer. Products sold through resellers are shipped directly to the end customer and are recognized when title transfers to the end customer. Revenue from resellers has predominantly been recorded on a gross basis for all periods presented. The Company records reductions to revenue for estimated sales returns and customer credits at the time the related revenue is recognized. Sales returns and customer credits are estimated based on historical experience, current trends and expectations regarding future experience. Customer billings related to taxes imposed by and remitted to governmental authorities on revenue-producing transactions are reported on a net basis. When such remitted taxes exceed the amount billed to customers, the cost is included in general and administrative expenses. Amounts billed in excess of revenue recognized for the period are reported as deferred revenue on the consolidated balance sheet. The Company’s deferred revenue consists primarily of unearned revenue on annual and monthly subscription plans. The Company received one-time up-front payments for implementation services to be performed in connection with its carrier agreements with BT and TELUS during the year ended December 31, 2014. These amounts are being amortized on a straight-line basis over their respective initial contractual terms beginning in 2015. The BT and TELUS arrangements have initial contractual terms of three to five years, which approximates the estimated average customer life of each respective agreement. Accordingly, the portion of these one-time up-front payments that is estimated to be realized beyond December 31, 2016, or $1.1 million, is included as a component of other long-term liabilities in the consolidated balance sheets.
Cost of Revenues	Cost of Revenues Cost of software subscriptions revenue primarily consists of costs of network capacity purchased from third-party telecommunications providers, network operations, costs to equip and maintain data centers, including co-location fees for the right to place the Company’s servers in data centers owned by third-parties, depreciation of the servers and equipment, along with related utilities and maintenance costs. Cost of software subscriptions revenue also includes personnel costs associated with non-administrative customer care and support of the functionality of the Company’s platform and data center operations, including share-based compensation expenses and allocated costs of facilities and information technology. Cost of software subscriptions revenue is expensed as incurred. Cost of product revenue is comprised primarily of the cost associated with purchased phones, shipping costs, as well as personnel costs for contractors and allocated costs of facilities and information technology related to the procurement, management and shipment of phones. Cost of product revenue is expensed in the period product is delivered to the customer.
Share-Based Compensation	Share-Based Compensation All share-based compensation resulting from options, restricted stock units (RSUs) and employee stock purchase plan rights granted to employees under our stock plans are measured as the grant date fair value of the award and recognized in the consolidated statements of operations over the requisite service period, which is generally the vesting period. The Company estimates the fair value of stock options and ESPP rights using the Black-Scholes-Merton option-pricing model. Compensation expense is recognized using the straight-line method net of estimated forfeitures. Share-based compensation expense resulting from stock options granted to non-employees is calculated using the Black-Scholes-Merton option-pricing model and RSUs value is measured as the grant date fair value of the award and is recognized in the consolidated statements of operations over the service period. Compensation expense for non-employee stock options and RSUs subject to vesting is revalued, or marked to market, as of each reporting date until the stock options and RSUs are vested.
Research and Development	Research and Development Research and development expenses consist primarily of third-party contractor costs, personnel costs, technology license expenses, and depreciation associated with research and development equipment. Research and development costs are expensed as incurred. Internal-use software development costs that qualify for capitalization are amortized to cost of sales over the estimated useful life of the software.
Advertising Costs	Advertising Costs Advertising costs, which include various forms of e-commerce such as search engine marketing, search engine optimization and online display advertising, as well as more traditional forms of media advertising such as radio and billboards, are expensed as incurred and were $34.3 million, $27.1 million, and $22.9 million for the years ended December 31, 2015, 2014 and 2013, respectively.
Commissions	Commissions Commissions consist of variable compensation earned by sales personnel and third-party resellers. Sales commissions associated with the acquisition of a new customer contract are recognized as sales and marketing expense at the time the customer has entered into a binding agreement.
Income Taxes	Income Taxes The Company accounts for income taxes using the asset and liability method. Deferred tax assets and liabilities are recognized for the estimated future tax consequences attributable to differences between the financial statement carrying amounts of existing assets and liabilities and their respective tax basis. Deferred tax assets and liabilities are measured using enacted tax rates in effect for the year in which those temporary differences are expected to be recovered or settled. The effect on deferred tax assets and liabilities of a change in tax rates is recognized in operations in the period that includes the enactment date. The Company records a valuation allowance to reduce its deferred tax assets to the amount of future tax benefit that is more likely than not to be realized. As of December 31, 2015, except for deferred tax assets associated with its subsidiaries in the Netherlands and China, the Company recorded a full valuation allowance against all other net deferred tax assets due to its history of operating losses. The Company classifies interest and penalties on unrecognized tax benefits as income tax expense.
Segment Information	Segment Information The Company has determined the chief executive officer is the chief operating decision maker. The Company’s chief executive officer reviews financial information presented on a consolidated basis for purposes of assessing performance and making decisions on how to allocate resources. Accordingly, the Company has determined that it operates in a single reporting segment.
Indemnification	Indemnification Certain of the Company’s agreements with resellers and customers include provisions for indemnification against liabilities if its subscriptions infringe a third-party’s intellectual property rights. At least quarterly, the Company assesses the status of any significant matters and its potential financial statement exposure. If the potential loss from any claim or legal proceeding is considered probable and the amount or the range of loss can be estimated, the Company accrues a liability for the estimated loss. The Company has not incurred any material costs as a result of such indemnification provisions and the Company has not accrued any liabilities related to such obligations in the consolidated financial statements as of December 31, 2015 or 2014.
Recent Accounting Pronouncements	Recent Accounting Pronouncements In May 2014, the Financial Accounting Standards Board (the “FASB”) issued Accounting Standards Update (ASU) No. 2014-09, Revenue from Contracts with Customers (Topic 606) In September 2015, the FASB issued ASU No. 2015-16, Business Combinations (Topic 805): Simplifying the Accounting for Measurement-Period Adjustments In November 2015, the FASB issued ASU No. 2015-17, Balance Sheet Classification of Deferred Taxes In February 2016, the FASB issued ASU 2016-02, Leases

Description of Business and S25

Description of Business and Summary of Significant Accounting Policies (Tables)	12 Months Ended
	Dec. 31, 2015
Organization Consolidation And Presentation Of Financial Statements [Abstract]
Changes in Allowance for Doubtful Accounts	Below is a summary of the changes in allowance for doubtful accounts for the years ended December 31, 2015, 2014 and 2013 (in thousands): Balance at Beginning of Period Provision, net of Recoveries Write-offs Balance at End of Period Year ended December 31, 2015 Allowance for doubtful accounts $ 125 $ 411 $ 159 $ 377 Year ended December 31, 2014 Allowance for doubtful accounts $ 139 $ 40 $ 54 $ 125 Year ended December 31, 2013 Allowance for doubtful accounts $ 433 $ (8 ) $ 286 $ 139

Financial Statement Components

Financial Statement Components (Tables)	12 Months Ended
	Dec. 31, 2015
Statement Of Financial Position [Abstract]
Components of Cash and Cash Equivalents	Cash and cash equivalents consisted of the following (in thousands): December 31, December 31, 2015 2014 Cash $ 18,422 $ 12,800 Money market funds 119,166 100,382 Total cash and cash equivalents $ 137,588 $ 113,182
Components of Accounts Receivable, Net	Accounts receivable, net consisted of the following (in thousands): December 31, December 31, 2015 2014 Accounts receivable $ 15,509 $ 5,935 Unbilled accounts receivable 4,031 1,841 Allowance for doubtful accounts (377 ) (125 ) Accounts receivable, net $ 19,163 $ 7,651
Components of Property and Equipment, Net	Property and equipment, net consisted of the following (in thousands): December 31, December 31, 2015 2014 Computer hardware and software $ 49,774 $ 43,805 Internal-use software development costs 7,432 5,335 Furniture and fixtures 3,610 2,020 Leasehold improvements 2,412 2,870 Property and equipment, gross 63,228 54,030 Less: accumulated depreciation and amortization (35,068 ) (28,503 ) Property and equipment, net $ 28,160 $ 25,527
Components of Accrued Liabilities	Accrued liabilities consisted of the following (in thousands): December 31, December 31, 2015 2014 Accrued compensation and benefits $ 10,128 $ 7,596 Accrued sales, use and telecom related taxes 5,243 5,277 Other accrued expenses 19,331 16,363 Total accrued liabilities $ 34,702 $ 29,236

Fair Value of Financial Instr27

Fair Value of Financial Instruments (Tables)	12 Months Ended
	Dec. 31, 2015
Fair Value Disclosures [Abstract]
Financial Assets Carried at Fair Value	The financial assets carried at fair value were determined using the following inputs (in thousands): Balance at December 31, (Level 1) (Level 2) (Level 3) Cash equivalents: Money market funds $ 119,166 $ 119,066 $ 100 $ — Other assets: Certificates of deposit $ 530 $ — $ 530 $ — Balance at December 31, (Level 1) (Level 2) (Level 3) Cash equivalents: Money market funds $ 100,570 $ 94,274 $ 6,296 $ — Short-term investments: Corporate debt securities $ 26,481 $ 26,481 $ — $ — Commercial paper $ 1,998 $ — $ 1,998 $ — Other assets: Certificates of deposit $ 630 $ — $ 630 $ —
Components of Available-for-Sale Securities	At December 31, 2014, available-for-sale securities consisted of the following (in thousands): Available-for-Sale Securities Amortized Cost Gross Unrealized Gains Gross Unrealized Losses Estimated Fair Value Corporate debt securities $ 26,700 $ 45 $ (264 ) $ 26,481 Commercial paper 1,996 2 — 1,998 Total $ 28,696 $ 47 $ (264 ) $ 28,479
Expected Maturities of Investments in Available-for-Sale Securities	The expected maturities of our investments in available-for-sale securities at December 31, 2014 are shown below (in thousands): Available-for-Sale Securities Amortized Cost Estimated Fair Value Due in less than one year $ 28,696 $ 28,479 Total $ 28,696 $ 28,479

Business Combinations (Tables)

Business Combinations (Tables)	12 Months Ended
	Dec. 31, 2015
Summary of Consideration Exchanged	The consideration exchanged consisted of the following (in thousands): Cash, net of cash acquired $ 4,670 Common stock issued (223,190 shares) 3,447 Holdback based on standard representations and warranties 1,500 Total initial consideration 9,617 Milestone based earn out (after valuation adjustment) 2,289 Total consideration $ 11,906
Summary of Fair Value of Assets Acquired	The following table summarizes the fair value of assets acquired as of the date of acquisition (in thousands): Cash and cash equivalents $ 74 Acquired intangible assets 3,850 Goodwill 7,982 Net assets acquired $ 11,906
Summary of Fair Value Components of Identifiable Acquired Intangible Assets And Their Estimated Useful Lives	The following table sets forth the fair value components of identifiable acquired intangible assets (in thousands) and their estimated useful lives (in years) as of the date of acquisition: Fair Value Estimated Useful Life Customer relationships $ 840 2 years Developed technology 3,010 5 years Total identifiable acquired intangible assets subject to amortization $ 3,850
Summary of Acquired Intangible Assets	Acquired intangible assets as of December 31, 2015 were as follows (in thousands): Gross Carrying Amount Accumulated Amortization Acquired Intangibles, Net Customer relationships $ 840 $ 240 $ 600 Developed technology 3,010 344 2,666 Total acquired intangible assets $ 3,850 $ 584 $ 3,266
Glip, Inc.
Summary of Estimated Amortization Expense for Acquired Intangible Assets	Estimated amortization expense for acquired intangible assets for the following five fiscal years and thereafter is as follows (in thousands): 2016 $ 1,022 2017 782 2018 602 2019 602 2020 258 Total estimated amortization expense $ 3,266

Debt (Tables)

Debt (Tables)	12 Months Ended
	Dec. 31, 2015
Debt Disclosure [Abstract]
Components of Debt Instrument	The Company’s outstanding balances under its debt agreements as of December 31, 2015 and 2014 were as follows (in thousands): December 31, 2015 2014 SVB loan and security agreement $ 18,590 $ 23,008 TriplePoint equipment loan agreement — 1,725 18,590 24,733 Loan discounts — (156 ) Net carrying value of debt $ 18,590 $ 24,577 Less: Current portion of long-term debt (3,750 ) (16,764 ) Long-term debt $ 14,840 $ 7,813
Schedule of Future Debt Principal Payments	As of December 31, 2015, future debt principal payments are scheduled as follows (in thousands): Year ending December 31, 2016 $ 3,750 2017 14,527 2018 313 $ 18,590

Commitments and Contingencies (

Commitments and Contingencies (Tables)	12 Months Ended
	Dec. 31, 2015
Commitments And Contingencies Disclosure [Abstract]
Schedule of Future Minimum Lease Payments for Capital and Operating Leases	As of December 31, 2015, non-cancelable leases expire on various dates between 2016 and 2021 and require the following future minimum lease payments by year (in thousands): Capital Leases Operating Leases Year ending December 31, 2016 $ 301 $ 5,383 2017 185 5,080 2018 — 4,922 2019 — 4,243 2020 — 3,449 2021 — 2,072 Total future minimum lease payments 486 $ 25,149 Less: amount representing interest (36 ) Total capital lease obligation 450 Less: Current portion of capital lease obligation (269 ) Capital lease obligation $ 181
Property and Equipment Recorded Under Capital Leases	Property and equipment recorded under capital leases consisted of the following (in thousands): December 31, 2015 2014 Property and equipment acquired under capital lease $ 3,149 $ 3,466 Less: accumulated amortization (2,212 ) (2,129 ) Property and equipment acquired under capital lease, net $ 937 $ 1,337

Stockholders' Equity (Tables)

Stockholders' Equity (Tables)	12 Months Ended
	Dec. 31, 2015
Equity [Abstract]
Schedule of Common Stock Reserved for Issuance	Shares of Class A common stock reserved for future issuance were as follows (in thousands): December 31, 2015 Preferred stock 100,000 Class B common stock 13,483 2013 Employee stock purchase plan 1,899 2013 Equity incentive plan: Outstanding options and restricted stock unit awards 10,337 Available for future grants 7,764 133,483

Share-Based Compensation (Table

Share-Based Compensation (Tables)	12 Months Ended
	Dec. 31, 2015
Disclosure Of Compensation Related Costs Sharebased Payments [Abstract]
Summary of Share-Based Compensation Expense Recognized to Statements of Operations	A summary of share-based compensation expense recognized in the Company’s consolidated statements of operations follows (in thousands): Year Ended December, 31 2015 2014 2013 Cost of software subscriptions revenue $ 2,054 $ 1,294 $ 539 Research and development 5,387 3,343 1,495 Sales and marketing 7,200 5,260 1,313 General and administrative 7,447 5,619 4,193 Total share-based compensation expense $ 22,088 $ 15,516 $ 7,540
Summary of Share-Based Compensation Expense by Award Type	A summary of share-based compensation expense by award type follows (in thousands): Year Ended December, 31 2015 2014 2013 Options $ 11,170 $ 10,323 $ 7,069 Employee stock purchase plan rights 1,365 1,628 453 Restricted stock units 9,553 3,565 18 Total share-based compensation expense $ 22,088 $ 15,516 $ 7,540
Summary of Stock Option Activity Plans	A summary of option activity under all of the plans at December 31, 2015 and changes during the periods then ended is presented in the following table: Weighted- Number of Weighted- Average Aggregate Options Average Contractual Intrinsic Outstanding Exercise Price Term Value (in thousands) Per Share (in Years) (in thousands) Outstanding at December 31, 2012 8,609 $ 2.89 7.2 $ 40,705 Granted 3,856 11.54 Exercised (607 ) 1.47 Canceled/Forfeited (702 ) 4.31 Outstanding at December 31, 2013 11,156 $ 5.87 7.7 $ 139,484 Granted 1,302 15.12 Exercised (2,673 ) 1.97 Canceled/Forfeited (627 ) 7.19 Outstanding at December 31, 2014 9,158 $ 8.23 7.2 $ 61,367 Granted 1,881 16.35 Exercised (2,323 ) 6.82 Canceled/Forfeited (668 ) 11.42 Outstanding at December 31, 2015 8,048 $ 10.27 6.2 $ 107,091 Vested and expected to vest as of December 31, 2015 7,972 $ 10.26 6.2 $ 106,197 Exercisable as of December 31, 2015 4,750 $ 7.40 6.0 $ 76,843
Schedule of Total Intrinsic Values of Options Exercised	The total intrinsic values of options exercised were as follows (in thousands): Year Ended December 31, 2015 2014 2013 Total intrinsic value of options exercised $ 28,336 $ 41,454 $ 10,261
Weighted Average Assumptions Used to Fair Value of Stock Options Granted	The weighted-average assumptions used in the option-pricing models and the resulting grant date fair value of stock options granted in the periods presented were as follows: Year ended December 31, 2015 2014 2013 Expected term for employees (in years) 4.8 4.6 6.1 Expected term for non-employees (in years) 7.0 7.0 10.0 Expected volatility 48 % 48 % 54 % Risk-free interest rate 1.22 % 1.41 % 1.68 % Expected dividend yield 0 % 0 % 0 % Grant date fair value of employee options $ 6.78 $ 6.16 $ 6.19
Summary of Assumptions Used to Value ESPP Rights Under the Black-Scholes Option-Pricing Model	The weighted-average assumptions used to value ESPP rights under the Black-Scholes-Merton option-pricing model and the resulting offering grant date fair value of ESPP rights granted in the periods presented were as follows: Year ended December 31, 2015 2014 Expected term (in years) 0.5 0.5 Expected volatility 42 % 50 % Risk-free interest rate 0.25 % 0.07 % Expected dividend yield 0 % 0 % Offering grant date fair value of ESPP rights $ 5.05 $ 3.93
Summary of RSUs Activity	The 2013 Plan provides for the issuance of restricted stock units (RSUs) to employees and consultants. RSUs issued under the 2013 Plan generally vest over four years. A summary of activity of RSUs under the 2013 Plan at December 31, 2015 and changes during the periods then ended is presented in the following table: Number of Weighted- Aggregate RSUs Average Intrinsic Outstanding Grant Date Fair Value (in thousands) Value Per Share (in thousands) Outstanding at December 31, 2013 68 $ 17.22 $ 1,251 Granted 1,915 15.08 Released (110 ) 16.82 Canceled/Forfeited (134 ) 17.43 Outstanding at December 31, 2014 1,739 $ 14.87 $ 25,617 Granted 1,365 18.09 Released (571 ) 15.45 Canceled/Forfeited (245 ) 15.10 Outstanding at December 31, 2015 2,288 $ 16.63 $ 53,972

Income Taxes (Tables)

Income Taxes (Tables)	12 Months Ended
	Dec. 31, 2015
Income Tax Disclosure [Abstract]
Summary of Provision (Benefit) from Continuing Operations on Basis of Segment Reporting	The provision (benefit) for income taxes consisted of the following (in thousands): Year ended December 31, 2015 2014 2013 Current: Federal $ — $ — $ — State 71 18 3 Foreign 85 114 (32 ) Total current 156 132 (29 ) Deferred: Federal $ (1,312 ) $ — $ — State (99 ) — — Foreign (8 ) (35 ) (16 ) Total deferred (1,419 ) (35 ) (16 ) Total income tax provision (benefit) $ (1,263 ) $ 97 $ (45 )
Summary of Income from Continuing Operations Before Income Taxes on Basis of Segment Reporting	Net loss before provision (benefit) for income taxes consisted of the following (in thousands): Year ended December 31, 2015 2014 2013 United States $ (28,870 ) $ (50,065 ) $ (41,778 ) International (4,492 ) 1,822 (4,365 ) Total net loss before benefit for income taxes $ (33,362 ) $ (48,243 ) $ (46,143 )
Summary of Variation of Effective Provision (Benefit) for Income Taxes from Statutory Federal Income Tax Rate	The provision (benefit) for income tax differed from the amounts computed by applying the U.S. federal income tax rate of 34% to pretax loss as a result of the following (in thousands): Year ended December 31, 2015 2014 2013 Federal tax benefit at statutory rate $ (11,343 ) $ (16,403 ) $ (15,687 ) State tax, net of federal provision (benefit) (34 ) 12 2 Research and development credits (667 ) (654 ) (774 ) Share-based compensation 1,086 1,836 641 Other permanent differences 325 211 294 Foreign tax rate differential (80 ) (33 ) (20 ) Net operating losses not recognized 10,762 15,128 15,499 Release of valuation allowance associated with acquisitions (1,312 ) — — Total income tax provision (benefit) $ (1,263 ) $ 97 $ (45 )
Schedule of Deferred Income Tax Assets and Liabilities	The types of temporary differences that give rise to significant portions of the Company’s deferred tax assets and liabilities are as follows (in thousands): Year ended December 31, 2015 2014 2013 Deferred tax assets Net operating loss and credit carry-forwards $ 54,858 $ 45,552 $ 35,904 Research and development credits 4,712 3,497 2,353 Sales tax liability 1,337 1,442 1,418 Share-based compensation 6,694 5,560 2,247 Accrued liabilities 6,090 4,676 2,528 Gross deferred tax assets 73,691 60,727 44,450 Valuation allowance (71,514 ) (60,405 ) (44,032 ) Total deferred tax assets 2,177 322 418 Deferred tax liabilities - Acquired intangibles (1,164 ) — — Deferred tax liabilities - Property and equipment (883 ) (197 ) (327 ) Net deferred tax assets $ 130 $ 125 $ 91
Summary of Reconciliation of Beginning and Ending Amount of Unrecognized Tax Benefits	The Company has adopted the accounting policy that interest and penalties recognized are classified as part of its income taxes. The following shows the changes in the gross amount of unrecognized tax benefits as of December 31, 2015 (in thousands): Balance as of December 31, 2013 $ 933 Gross amount of increases in unrecognized tax benefits for tax positions taken in current year 465 Gross amount of increases in unrecognized tax benefits for tax positions taken in prior year 1,217 Balance as of December 31, 2014 $ 2,615 Gross amount of increases in unrecognized tax benefits for tax positions taken in current year 499 Gross amount of decreases in unrecognized tax benefits for tax positions taken in prior year (1,217 ) Balance as of December 31, 2015 $ 1,897

Basic and Diluted Net Loss Pe34

Basic and Diluted Net Loss Per Share (Tables)	12 Months Ended
	Dec. 31, 2015
Earnings Per Share [Abstract]
Computation of Company's Basic and Diluted Net Loss Per Share of Common Stock	The following table sets forth the computation of the Company’s basic and diluted net loss per share during the years ended December 31, 2015, 2014 and 2013 (in thousands, except per share data): Year Ended December 31, 2015 2014 2013 Numerator Net loss $ (32,099 ) $ (48,340 ) $ (46,098 ) Denominator Weighted-average common shares for basic and diluted net loss per share 70,069 66,818 33,155 Basic and diluted net loss per share $ (0.46 ) $ (0.72 ) $ (1.39 )
Potential Shares of Common Stock Excluded from Diluted Weighted-Average Common Shares Outstanding	Following is a table summarizing the potentially dilutive common shares that were excluded from diluted weighted-average common shares outstanding (in thousands): Year Ended December 31, 2015 2014 2013 Shares of common stock issuable upon conversion of warrants — — 502 Shares of common stock subject to repurchase 2 15 37 Shares of common stock issuable under equity incentive plans outstanding 10,337 10,897 11,224 Potential common shares excluded from diluted net loss per share 10,339 10,912 11,763

Selected Quarterly Financial 35

Selected Quarterly Financial Data (Unaudited) (Tables)	12 Months Ended
	Dec. 31, 2015
Quarterly Financial Information Disclosure [Abstract]
Selected Unaudited Quarterly Consolidated Statements of Operations Data	The following tables set forth selected unaudited quarterly consolidated statements of operations data for each of the eight quarters in the years ended December 31, 2015 and 2014 (in thousands except per share data): Quarter ended Dec 31, Sept 30, 2015 June 30, 2015 Mar 31, 2015 Dec 31, 2014 Sept 30, 2014 June 30, 2014 Mar 31, 2014 Consolidated Statements of Operations Data: Revenues $ 83,439 $ 76,780 $ 70,691 $ 65,318 $ 61,893 $ 56,944 $ 52,787 $ 48,262 Gross profit 60,577 54,447 49,162 44,771 41,972 37,539 33,244 30,359 Operating loss (5,996 ) (5,828 ) (9,539 ) (9,569 ) (9,343 ) (10,814 ) (12,810 ) (12,238 ) Net Loss (6,941 ) (6,336 ) (8,211 ) (10,611 ) (10,120 ) (11,986 ) (13,330 ) (12,904 ) Net Loss per share, basic and diluted $ (0.10 ) $ (0.09 ) $ (0.12 ) $ (0.15 ) $ (0.15 ) $ (0.18 ) $ (0.20 ) $ (0.20 )

Description of Business and S36

Description of Business and Summary of Significant Accounting Policies - Additional Information (Detail) - USD ($)	Mar. 11, 2014	Oct. 02, 2013	Dec. 31, 2015	Dec. 31, 2015	Dec. 31, 2014	Dec. 31, 2013
Description Of Business And Summary Of Significant Accounting Policies [Line Items]
Deferred offering costs					$ 1,219,000	$ 3,720,000
Proceeds from issuance of common stock					57,167,000	103,309,000
Marketable securities			$ 0	$ 0
Impairment losses of investments				0	0	0
Asset impairment charges			1,300,000	1,317,000	0	0
Software development cost incurred, net of impairment				2,100,000	700,000
Internal-use software development costs, net of amortization			$ 2,600,000	$ 2,600,000	1,700,000
Concentration Risk, Customer				For the year ended December 31, 2013, no single customer or reseller accounted for greater than 10% of the Company’s total revenues.
Advertising Expense				$ 34,300,000	$ 27,100,000	$ 22,900,000
TELUS And British Telecom
Description Of Business And Summary Of Significant Accounting Policies [Line Items]
One time upfront payment				$ 1,100,000
Accounts receivable | Customer A
Description Of Business And Summary Of Significant Accounting Policies [Line Items]
Concentration risk, percentage				39.00%	44.00%
Revenues | Customer A
Description Of Business And Summary Of Significant Accounting Policies [Line Items]
Concentration risk, percentage				13.00%	12.00%
Software subscription revenues | Customer A
Description Of Business And Summary Of Significant Accounting Policies [Line Items]
Concentration risk, percentage				12.00%	11.00%
Minimum
Description Of Business And Summary Of Significant Accounting Policies [Line Items]
Contractual arrangement subscriptions period				1 month
Minimum | TELUS And British Telecom
Description Of Business And Summary Of Significant Accounting Policies [Line Items]
TELUS and BT transaction agreement initial, term years				3 years
Maximum
Description Of Business And Summary Of Significant Accounting Policies [Line Items]
Contractual arrangement subscriptions period				3 years
Maximum | TELUS And British Telecom
Description Of Business And Summary Of Significant Accounting Policies [Line Items]
TELUS and BT transaction agreement initial, term years				5 years
Furniture and Fixtures | Minimum
Description Of Business And Summary Of Significant Accounting Policies [Line Items]
Property and Equipment, useful lives				3 years
Furniture and Fixtures | Maximum
Description Of Business And Summary Of Significant Accounting Policies [Line Items]
Property and Equipment, useful lives				5 years
Computer Hardware and Software | Minimum
Description Of Business And Summary Of Significant Accounting Policies [Line Items]
Property and Equipment, useful lives				3 years
Computer Hardware and Software | Maximum
Description Of Business And Summary Of Significant Accounting Policies [Line Items]
Property and Equipment, useful lives				5 years
Internal-use software development costs | Minimum
Description Of Business And Summary Of Significant Accounting Policies [Line Items]
Amortized useful lives				3 years
Internal-use software development costs | Maximum
Description Of Business And Summary Of Significant Accounting Policies [Line Items]
Amortized useful lives				4 years
Class A common stock | Initial Public Offering
Description Of Business And Summary Of Significant Accounting Policies [Line Items]
Common stock, shares issued		8,625,000
Sale of stock, price per share		$ 13
Proceeds from issuance of initial public offering		$ 103,300,000
Deferred offering costs		$ 3,900,000
Class A common stock | Secondary Public Offering
Description Of Business And Summary Of Significant Accounting Policies [Line Items]
Common stock, shares issued	7,991,551
Sale of stock, price per share	$ 21.50
Deferred offering costs	$ 1,100,000
Proceeds from issuance of common stock	$ 57,200,000
Overallotment Option | Class A common stock | Initial Public Offering
Description Of Business And Summary Of Significant Accounting Policies [Line Items]
Common stock, shares issued		1,125,000
Overallotment Option | Class A common stock | Secondary Public Offering
Description Of Business And Summary Of Significant Accounting Policies [Line Items]
Common stock, shares issued	791,551
Selling Stockholders | Class A common stock | Initial Public Offering
Description Of Business And Summary Of Significant Accounting Policies [Line Items]
Common stock, shares issued		80,000
Selling Stockholders | Class A common stock | Secondary Public Offering
Description Of Business And Summary Of Significant Accounting Policies [Line Items]
Common stock, shares issued	5,200,000

Changes in Allowance for Doubtf

Changes in Allowance for Doubtful Accounts (Detail) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2015	Dec. 31, 2014	Dec. 31, 2013
Receivables [Abstract]
Balance at Beginning of Period	$ 125	$ 139	$ 433
Provision, net of Recoveries	411	40	(8)
Write-offs	159	54	286
Balance at End of Period	$ 377	$ 125	$ 139

Financial Statement Component38

Financial Statement Components - Components of Cash and Cash Equivalents (Detail) - USD ($) $ in Thousands	Dec. 31, 2015	Dec. 31, 2014	Dec. 31, 2013	Dec. 31, 2012
Cash And Cash Equivalents [Abstract]
Cash	$ 18,422	$ 12,800
Money market funds	119,166	100,382
Total cash and cash equivalents	$ 137,588	$ 113,182	$ 116,378	$ 37,864

Financial Statement Component39

Financial Statement Components - Components of Accounts Receivable, Net (Detail) - USD ($) $ in Thousands	Dec. 31, 2015	Dec. 31, 2014	Dec. 31, 2013	Dec. 31, 2012
Receivables [Abstract]
Accounts receivable	$ 15,509	$ 5,935
Unbilled accounts receivable	4,031	1,841
Allowance for doubtful accounts	(377)	(125)	$ (139)	$ (433)
Accounts receivable, net	$ 19,163	$ 7,651

Financial Statement Component40

Financial Statement Components - Components of Property and Equipment, Net (Detail) - USD ($) $ in Thousands	Dec. 31, 2015	Dec. 31, 2014
Property Plant And Equipment [Line Items]
Property and equipment, gross	$ 63,228	$ 54,030
Less: accumulated depreciation and amortization	(35,068)	(28,503)
Property and equipment, net	28,160	25,527
Computer hardware and software
Property Plant And Equipment [Line Items]
Property and equipment, gross	49,774	43,805
Internal-use software development costs
Property Plant And Equipment [Line Items]
Property and equipment, gross	7,432	5,335
Furniture and fixtures
Property Plant And Equipment [Line Items]
Property and equipment, gross	3,610	2,020
Leasehold improvements
Property Plant And Equipment [Line Items]
Property and equipment, gross	$ 2,412	$ 2,870

Financial Statement Component41

Financial Statement Components - Additional Information (Detail) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2015	Dec. 31, 2014	Dec. 31, 2013
Statement Of Financial Position [Abstract]
Depreciation and amortization	$ 13,467	$ 10,378	$ 8,980

Financial Statement Component42

Financial Statement Components - Components of Accrued Liabilities (Detail) - USD ($) $ in Thousands	Dec. 31, 2015	Dec. 31, 2014
Payables And Accruals [Abstract]
Accrued compensation and benefits	$ 10,128	$ 7,596
Accrued sales, use and telecom related taxes	5,243	5,277
Other accrued expenses	19,331	16,363
Total accrued liabilities	$ 34,702	$ 29,236

Fair Value of Financial Instr43

Fair Value of Financial Instruments - Financial Assets Carried at Fair Value (Detail) - USD ($) $ in Thousands	Dec. 31, 2015	Dec. 31, 2014
Fair Value Assets And Liabilities Measured On Recurring And Nonrecurring Basis [Line Items]
Short-term investments		$ 28,479
Fair Value, Measurements, Recurring | Money market funds
Fair Value Assets And Liabilities Measured On Recurring And Nonrecurring Basis [Line Items]
Money market funds	$ 119,166	100,570
Fair Value, Measurements, Recurring | Money market funds | Level 1
Fair Value Assets And Liabilities Measured On Recurring And Nonrecurring Basis [Line Items]
Money market funds	119,066	94,274
Fair Value, Measurements, Recurring | Money market funds | Level 2
Fair Value Assets And Liabilities Measured On Recurring And Nonrecurring Basis [Line Items]
Money market funds	100	6,296
Fair Value, Measurements, Recurring | Certificates of deposit
Fair Value Assets And Liabilities Measured On Recurring And Nonrecurring Basis [Line Items]
Certificates of deposit	530	630
Fair Value, Measurements, Recurring | Certificates of deposit | Level 2
Fair Value Assets And Liabilities Measured On Recurring And Nonrecurring Basis [Line Items]
Certificates of deposit	$ 530	630
Fair Value, Measurements, Recurring | Corporate debt securities
Fair Value Assets And Liabilities Measured On Recurring And Nonrecurring Basis [Line Items]
Short-term investments		26,481
Fair Value, Measurements, Recurring | Corporate debt securities | Level 1
Fair Value Assets And Liabilities Measured On Recurring And Nonrecurring Basis [Line Items]
Short-term investments		26,481
Fair Value, Measurements, Recurring | Commercial paper
Fair Value Assets And Liabilities Measured On Recurring And Nonrecurring Basis [Line Items]
Short-term investments		1,998
Fair Value, Measurements, Recurring | Commercial paper | Level 2
Fair Value Assets And Liabilities Measured On Recurring And Nonrecurring Basis [Line Items]
Short-term investments		$ 1,998

Fair Value of Financial Instr44

Fair Value of Financial Instruments - Additional Information (Detail) - USD ($) $ in Thousands	3 Months Ended	12 Months Ended
	Sep. 30, 2014	Dec. 31, 2015	Dec. 31, 2014
Fair Value Inputs Liabilities Quantitative Information [Line Items]
Maturity year of investments		2,015
Fair value of debt obligation		$ 19,000	$ 25,700
Carrying value of debt obligation		$ 18,590	$ 24,577
Commercial paper | Minimum
Fair Value Inputs Liabilities Quantitative Information [Line Items]
Maturity period of investments	5 months
Commercial paper | Maximum
Fair Value Inputs Liabilities Quantitative Information [Line Items]
Maturity period of investments	15 months
Corporate debt securities | Minimum
Fair Value Inputs Liabilities Quantitative Information [Line Items]
Maturity period of investments	5 months
Corporate debt securities | Maximum
Fair Value Inputs Liabilities Quantitative Information [Line Items]
Maturity period of investments	15 months

Fair Value of Financial Instr45

Fair Value of Financial Instruments - Components of Available-for-Sale Securities (Detail) $ in Thousands	Dec. 31, 2014USD ($)
Fair Value Inputs Assets Quantitative Information [Line Items]
Available-for-Sale Securities, Amortized Cost	$ 28,696
Available-for-Sale Securities, Gross Unrealized Gains	47
Available-for-Sale Securities, Gross Unrealized Losses	(264)
Available-for-Sale Securities, Estimated Fair Value	28,479
Corporate debt securities
Fair Value Inputs Assets Quantitative Information [Line Items]
Available-for-Sale Securities, Amortized Cost	26,700
Available-for-Sale Securities, Gross Unrealized Gains	45
Available-for-Sale Securities, Gross Unrealized Losses	(264)
Available-for-Sale Securities, Estimated Fair Value	26,481
Commercial paper
Fair Value Inputs Assets Quantitative Information [Line Items]
Available-for-Sale Securities, Amortized Cost	1,996
Available-for-Sale Securities, Gross Unrealized Gains	2
Available-for-Sale Securities, Estimated Fair Value	$ 1,998

Fair Value of Financial Instr46

Fair Value of Financial Instruments - Expected Maturities of Investment in Available-for-Sale Securities (Detail) $ in Thousands	Dec. 31, 2014USD ($)
Available-for-Sale Securities, Amortized Cost
Due in less than one year, Amortized Cost	$ 28,696
Available-for-Sale Securities, Amortized Cost	28,696
Available-for-Sale Securities, Estimated Fair Value
Due in less than one year, Estimated Fair Value	28,479
Total, Estimated Fair Value	$ 28,479

Business Combinations - Additio

Business Combinations - Additional Information (Detail) - Glip, Inc. - USD ($)	Jun. 04, 2015	Dec. 31, 2015
Business Acquisition [Line Items]
Business combination, consideration payable in combination of cash and common stock	$ 11,906,000
Business combination contingent consideration maximum potential cash payment		$ 2,000,000
Business combination earn out period of contingent consideration		2 years
Business combination, contingent payment liability		$ 600,000
Business combination, fair value of milestone based earn out liability	$ 2,289,000	2,400,000
Amortization expense of Intangible Assets		$ 600,000
Customer Relationships
Business Acquisition [Line Items]
Weighted-average amortization periods	1 year 4 months 24 days
Developed Technology
Business Acquisition [Line Items]
Weighted-average amortization periods	4 years 4 months 24 days
Common Stock
Business Acquisition [Line Items]
Business combination, fair value of consideration shares net amount	$ 3,447,000
Business combination, consideration common stock issued	223,190
Business combination, consideration shares gross amount	$ 3,800,000
Business combination, consideration shares marketability discount	$ 400,000

Business Combinations - Summary

Business Combinations - Summary of Consideration Exchanged (Detail) - USD ($) $ in Thousands	Jun. 04, 2015	Dec. 31, 2015
Business Acquisition [Line Items]
Cash, net of cash acquired		$ 4,670
Glip, Inc.
Business Acquisition [Line Items]
Cash, net of cash acquired	$ 4,670
Holdback based on standard representations and warranties	1,500
Total initial consideration	9,617
Milestone based earn out (after valuation adjustment)	2,289	$ 2,400
Total consideration	11,906
Common Stock | Glip, Inc.
Business Acquisition [Line Items]
Common stock issued (223,190 shares)	$ 3,447

Business Combinations - Summa49

Business Combinations - Summary of Consideration Exchanged (Parenthetical) (Detail)	Jun. 04, 2015shares
Glip, Inc. | Common Stock
Business Acquisition [Line Items]
Business combination, consideration common stock issued	223,190

Business Combinations - Summa50

Business Combinations - Summary of Fair Value of Assets Acquired (Detail) - USD ($) $ in Thousands	Dec. 31, 2015	Jun. 04, 2015
Business Acquisition [Line Items]
Goodwill	$ 9,393
Glip, Inc.
Business Acquisition [Line Items]
Cash and cash equivalents		$ 74
Acquired intangible assets		3,850
Goodwill		7,982
Net assets acquired		$ 11,906

Business Combinations - Summa51

Business Combinations - Summary of Fair Value Components of Identifiable Acquired Intangible Assets And Their Estimated Useful Lives (Detail) - Glip, Inc. $ in Thousands	Jun. 04, 2015USD ($)
Business Acquisition [Line Items]
Total identifiable acquired intangible assets subject to amortization, Fair value	$ 3,850
Customer Relationships
Business Acquisition [Line Items]
Total identifiable acquired intangible assets subject to amortization, Fair value	$ 840
Total identifiable acquired intangible assets subject to amortization, Estimated useful life	2 years
Developed Technology
Business Acquisition [Line Items]
Total identifiable acquired intangible assets subject to amortization, Fair value	$ 3,010
Total identifiable acquired intangible assets subject to amortization, Estimated useful life	5 years

Business Combinations - Summa52

Business Combinations - Summary of Acquired Intangible Assets (Detail) $ in Thousands	Dec. 31, 2015USD ($)
Business Acquisition [Line Items]
Acquired Intangibles, Net	$ 3,266
Glip, Inc.
Business Acquisition [Line Items]
Gross Carrying Amount	3,850
Accumulated Amortization	584
Acquired Intangibles, Net	3,266
Glip, Inc. | Customer Relationships
Business Acquisition [Line Items]
Gross Carrying Amount	840
Accumulated Amortization	240
Acquired Intangibles, Net	600
Glip, Inc. | Developed Technology
Business Acquisition [Line Items]
Gross Carrying Amount	3,010
Accumulated Amortization	344
Acquired Intangibles, Net	$ 2,666

Business Combinations - Summa53

Business Combinations - Summary of Estimated Amortization Expense for Acquired Intangible Assets (Detail) $ in Thousands	Dec. 31, 2015USD ($)
Acquired Indefinite Lived Intangible Assets [Line Items]
Acquired Intangibles, Net	$ 3,266
Glip, Inc.
Acquired Indefinite Lived Intangible Assets [Line Items]
2,016	1,022
2,017	782
2,018	602
2,019	602
2,020	258
Acquired Intangibles, Net	$ 3,266

Debt - Additional Information (

Debt - Additional Information (Detail)	Dec. 31, 2013USD ($)Installment	Aug. 31, 2012USD ($)Installment	Mar. 31, 2012USD ($)Installment	Aug. 31, 2012USD ($)	Dec. 31, 2015USD ($)	Dec. 31, 2014USD ($)
Debt Instrument [Line Items]
Outstanding balance of term loan					$ 18,590,000	$ 24,733,000
Long-term debt					$ 14,840,000	7,813,000
Revolving Credit Facility
Debt Instrument [Line Items]
Interest rate on debt					3.50%
Revolving line of credit, maximum borrowing amount					$ 15,000,000
Line of credit facility, expiration date prior to amendment					Aug. 13, 2015
Debt instrument maturity date					Aug. 14, 2017
Borrowing under the revolving line of credit facility					$ 10,800,000
Line of credit, available borrowing capacity					$ 4,200,000
Required Cash Balances Maintained With Silicon Valley Bank | Prime Rate | Revolving Credit Facility
Debt Instrument [Line Items]
Percentage of margin					0.25%
Required Cash Balances Maintained With Silicon Valley Bank | LIBOR Rate | Revolving Credit Facility
Debt Instrument [Line Items]
Percentage of margin					3.25%
Required Cash Balances Not Maintained With Silicon Valley Bank | Prime Rate | Revolving Credit Facility
Debt Instrument [Line Items]
Percentage of margin					0.50%
Required Cash Balances Not Maintained With Silicon Valley Bank | LIBOR Rate | Revolving Credit Facility
Debt Instrument [Line Items]
Percentage of margin					3.50%
SVB Loan Agreement
Debt Instrument [Line Items]
Outstanding balance of term loan					$ 18,590,000	23,008,000
SVB Loan Agreement | Minimum
Debt Instrument [Line Items]
Debt covenant requirement					$ 10,000,000
Triple Point Equipment Term Loan
Debt Instrument [Line Items]
Term loan		$ 9,700,000		$ 9,700,000
Number of monthly installments for principal and interest payment | Installment		36
Percentage of final terminal payment of original loan principal at maturity				10.00%
Final terminal payment due at maturity				$ 1,000,000
Debt instrument maturity date, month and year					2015-03
Outstanding balance of term loan						$ 1,725,000
Term loan fixed interest rate		5.75%		5.75%
SVB Loan Agreement | 2012 Capital Growth Term Loan
Debt Instrument [Line Items]
Term loan			$ 8,000,000
Number of monthly installments for principal and interest payment | Installment			36
Interest rate on debt					3.50%
Percentage of final terminal payment of original loan principal at maturity					0.50%
Final terminal payment due at maturity					$ 40,000
Debt instrument maturity date, month and year					2015-03
SVB Loan Agreement | 2012 Capital Growth Term Loan | Required Cash Balances Maintained With Silicon Valley Bank | Prime Rate
Debt Instrument [Line Items]
Percentage of margin					0.25%
SVB Loan Agreement | 2012 Capital Growth Term Loan | Required Cash Balances Maintained With Silicon Valley Bank | LIBOR Rate
Debt Instrument [Line Items]
Percentage of margin					3.25%
SVB Loan Agreement | 2012 Capital Growth Term Loan | Required Cash Balances Not Maintained With Silicon Valley Bank | Prime Rate
Debt Instrument [Line Items]
Percentage of margin					0.50%
SVB Loan Agreement | 2012 Capital Growth Term Loan | Required Cash Balances Not Maintained With Silicon Valley Bank | LIBOR Rate
Debt Instrument [Line Items]
Percentage of margin					3.50%
SVB Loan Agreement | 2013 Capital Growth Term Loan
Debt Instrument [Line Items]
Term loan	$ 15,000,000
Number of monthly installments for principal and interest payment | Installment	48
Interest rate on debt					4.00%
Outstanding balance of term loan					$ 7,800,000
Long-term debt					$ 4,100,000
Debt instrument, maturity, description					due beyond December 31, 2016
SVB Loan Agreement | 2013 Capital Growth Term Loan | Required Cash Balances Maintained With Silicon Valley Bank | Prime Rate
Debt Instrument [Line Items]
Percentage of margin					0.75%
SVB Loan Agreement | 2013 Capital Growth Term Loan | Required Cash Balances Maintained With Silicon Valley Bank | LIBOR Rate
Debt Instrument [Line Items]
Percentage of margin					3.75%
SVB Loan Agreement | 2013 Capital Growth Term Loan | Required Cash Balances Not Maintained With Silicon Valley Bank | Prime Rate
Debt Instrument [Line Items]
Percentage of margin					1.00%
SVB Loan Agreement | 2013 Capital Growth Term Loan | Required Cash Balances Not Maintained With Silicon Valley Bank | LIBOR Rate
Debt Instrument [Line Items]
Percentage of margin					4.00%

Debt - Components of Debt Instr

Debt - Components of Debt Instrument (Detail) - USD ($) $ in Thousands	Dec. 31, 2015	Dec. 31, 2014
Debt Instrument [Line Items]
Long-term Debt, Gross	$ 18,590	$ 24,733
Loan discounts		(156)
Net carrying value of debt	18,590	24,577
Less: Current portion of long-term debt	(3,750)	(16,764)
Long-term debt	14,840	7,813
Silicon Valley Bank
Debt Instrument [Line Items]
Long-term Debt, Gross	$ 18,590	23,008
Triple Point Equipment Term Loan
Debt Instrument [Line Items]
Long-term Debt, Gross		$ 1,725

Debt - Schedule of Future Debt

Debt - Schedule of Future Debt Principal Payments (Detail) - USD ($) $ in Thousands	Dec. 31, 2015	Dec. 31, 2014
Debt Disclosure [Abstract]
2,016	$ 3,750
2,017	14,527
2,018	313
Long-term Debt, Gross	$ 18,590	$ 24,733

Commitments and Contingencies -

Commitments and Contingencies - Schedule of Future Minimum Lease Payments for Capital and Operating Leases (Detail) - USD ($) $ in Thousands	Dec. 31, 2015	Dec. 31, 2014
Capital leases
Capital leases due in 2016	$ 301
Capital leases due in 2017	185
Total future minimum lease payments	486
Less: amount representing interest	(36)
Total capital lease obligation	450
Less: Current portion of capital lease obligation	(269)	$ (509)
Capital lease obligation	181	$ 535
Operating leases
Operating leases due in 2016	5,383
Operating leases due in 2017	5,080
Operating leases due in 2018	4,922
Operating leases due in 2019	4,243
Operating leases due in 2020	3,449
Operating leases due in 2021	2,072
Total future minimum lease payments	$ 25,149

Commitments and Contingencies58

Commitments and Contingencies - Property and Equipment Recorded under Capital Leases (Detail) - USD ($) $ in Thousands	Dec. 31, 2015	Dec. 31, 2014
Property Plant And Equipment [Abstract]
Property and equipment acquired under capital lease	$ 3,149	$ 3,466
Less: accumulated amortization	(2,212)	(2,129)
Property and equipment acquired under capital lease, net	$ 937	$ 1,337

Commitments and Contingencies59

Commitments and Contingencies - Additional Information (Detail)	12 Months Ended
	Dec. 31, 2015USD ($)Legal_Matter	Dec. 31, 2014USD ($)Legal_Matter	Dec. 31, 2013USD ($)
Commitments And Contingencies Disclosure [Abstract]
Total rent expense	$ 4,000,000	$ 2,200,000	$ 1,300,000
Long-term sales tax liability	3,670,000	3,953,000
Current sales tax liability for non-contingent amounts	4,400,000	4,200,000
Accrued liabilities recorded for loss contingencies	$ 0	$ 0
Number of ongoing legal matters | Legal_Matter	0	0
Contingent liabilities related to employment agreement	$ 0

Stockholders' Equity - Addition

Stockholders' Equity - Additional Information (Detail) - $ / shares	12 Months Ended
	Dec. 31, 2015	Dec. 31, 2014
Stockholders Equity Note Disclosure [Line Items]
Preferred stock, par value	$ 0.0001
Preferred stock, shares authorized	100,000,000	100,000,000
Preferred stock, shares issued	0	0
Preferred stock, shares outstanding	0	0
Common stock, conversion basis	each share of Class B common stock will convert automatically to Class A common stock upon: (i) the date specified by an affirmative vote or written consent of holders of at least 67% of the outstanding shares of Class B common stock, or (ii) the seven year anniversary of the closing date of the IPO (October 2, 2020)
Year of anniversary	7 years
Anniversary Closing Date of the IPO	Oct. 2, 2020
Early Exercises of Nonvested Options
Stockholders Equity Note Disclosure [Line Items]
Common stock outstanding related to the early exercise of non-vested options	2,330	14,893
Class A common stock
Stockholders Equity Note Disclosure [Line Items]
Common stock, par or stated value per share	$ 0.0001	$ 0.0001
Common stock, shares authorized	1,000,000,000	1,000,000,000
Class B common stock
Stockholders Equity Note Disclosure [Line Items]
Common stock, par or stated value per share	$ 0.0001	$ 0.0001
Common stock, shares authorized	250,000,000	250,000,000
Percentage of written consent of shareholders	67.00%

Stockholders' Equity - Summary

Stockholders' Equity - Summary of Common Stock Reserved for Future Issuance (Detail)	Dec. 31, 2015shares
Class Of Stock [Line Items]
Common stock reserved for future issuance	133,483,000
2013 Equity incentive plan
Class Of Stock [Line Items]
Outstanding options and restricted stock unit awards	10,337,000
Available for future grants	7,764,035
2013 Employee stock purchase plan
Class Of Stock [Line Items]
Common stock reserved for future issuance	1,899,000
Available for future grants	1,898,792
Class B common stock
Class Of Stock [Line Items]
Common stock reserved for future issuance	13,483,000
Preferred Stock
Class Of Stock [Line Items]
Common stock reserved for future issuance	100,000,000

Share-Based Compensation - Summ

Share-Based Compensation - Summary of Share-Based Compensation Expense Recognized to Statements of Operations (Detail) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2015	Dec. 31, 2014	Dec. 31, 2013
Employee Service Share Based Compensation Allocation Of Recognized Period Costs [Line Items]
Share-based compensation expense	$ 22,088	$ 15,516	$ 7,540
Cost of Software Subscriptions Revenue
Employee Service Share Based Compensation Allocation Of Recognized Period Costs [Line Items]
Share-based compensation expense	2,054	1,294	539
Research and Development
Employee Service Share Based Compensation Allocation Of Recognized Period Costs [Line Items]
Share-based compensation expense	5,387	3,343	1,495
Sales and Marketing
Employee Service Share Based Compensation Allocation Of Recognized Period Costs [Line Items]
Share-based compensation expense	7,200	5,260	1,313
General and Administrative
Employee Service Share Based Compensation Allocation Of Recognized Period Costs [Line Items]
Share-based compensation expense	$ 7,447	$ 5,619	$ 4,193

Share-Based Compensation - Su63

Share-Based Compensation - Summary of Share-Based Compensation Expense by Award Type (Detail) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2015	Dec. 31, 2014	Dec. 31, 2013
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Share-based compensation expense	$ 22,088	$ 15,516	$ 7,540
Options
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Share-based compensation expense	11,170	10,323	7,069
Restricted Stock Units
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Share-based compensation expense	9,553	3,565	18
Employee Stock Purchase Plan Rights
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Share-based compensation expense	$ 1,365	$ 1,628	$ 453

Share-Based Compensation - Addi

Share-Based Compensation - Additional Information (Detail) - USD ($) $ in Millions	Jan. 29, 2014	Sep. 30, 2013	Dec. 31, 2015	Dec. 31, 2014	Dec. 31, 2015	Dec. 31, 2014	Dec. 31, 2013
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Common stock reserved for future issuance			133,483,000		133,483,000
Expected dividend yield					0.00%	0.00%	0.00%
2013 Employee stock purchase plan
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Common stock reserved for future issuance			1,899,000		1,899,000
Available for future grants			1,898,792		1,898,792
Expected dividend yield					0.00%	0.00%
Unrecognized share-based compensation expense, remaining weighted-average vesting periods					4 months 24 days	4 months 24 days
Eligible compensation under the Employee Stock Purchase Plan			15.00%		15.00%
Purchase of maximum shares by employees under Employee Stock Purchase Plan					3,000
Purchase price of Employee Stock Purchase Plan as a percentage of fair value					90.00%
Unrecognized share-based compensation expense			$ 1.1	$ 0.4	$ 1.1	$ 0.4
Employee Stock Option
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Unrecognized share-based compensation expense			19.6	20.1	$ 19.6	$ 20.1
Unrecognized share-based compensation expense, remaining weighted-average vesting periods					2 years 6 months	2 years 4 months 24 days
Restricted Stock Units
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Vesting period contractual term					4 years
RSUs
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Unrecognized share-based compensation expense, remaining weighted-average vesting periods					3 years	3 years 7 months 6 days
Unrecognized share-based compensation expense			$ 35.2	$ 24.2	$ 35.2	$ 24.2
Company's Historical Data
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Estimate expected weighting percentage			50.00%	25.00%
Simplified Method Estimate
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Estimate expected weighting percentage			50.00%	75.00%
Historical Volatilities of Peer Group
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Estimate expected weighting percentage				75.00%
Company's Historical Volatility
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Estimate expected weighting percentage			50.00%
Company’s Peer Group Volatilities
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Estimate expected weighting percentage			50.00%
Class A common stock
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Common stock, shares outstanding			58,480,000	50,770,000	58,480,000	50,770,000
Class A common stock | 2013 Employee stock purchase plan
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Common stock, shares outstanding			1,250,000		1,250,000
Percentage of outstanding shares of common stock					1.00%
Common stock shares, additional					685,584
2013 Equity incentive plan
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Percentage of outstanding shares of common stock					5.00%
Graded vesting schedule, number of years continuous service					4 years
Available for future grants			7,764,035		7,764,035
Vesting period contractual term	7 years
2013 Equity incentive plan | Previously Reported
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Vesting period contractual term		10 years
2013 Equity incentive plan | Class A common stock
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Common stock reserved for future issuance			6,200,000		6,200,000
Common stock, shares outstanding			6,200,000		6,200,000
Common stock shares, additional					3,427,922

Share-Based Compensation - Su65

Share-Based Compensation - Summary of Stock Option Activity Plans (Detail) - USD ($) $ / shares in Units, shares in Thousands, $ in Thousands	12 Months Ended
	Dec. 31, 2015	Dec. 31, 2014	Dec. 31, 2013	Dec. 31, 2012
Number of Options Outstanding
Number of Options Outstanding, Beginning Balance	9,158	11,156	8,609
Number of Options Outstanding, Granted	1,881	1,302	3,856
Number of Options Outstanding, Exercised	(2,323)	(2,673)	(607)
Number of Options Outstanding, Canceled/Forfeited	(668)	(627)	(702)
Number of Options Outstanding, Ending Balance	8,048	9,158	11,156	8,609
Number of Options Outstanding, Vested and expected to vest	7,972
Number of Options Outstanding, Exercisable	4,750
Weighted-Average Exercise Price Per Share
Weighted Average Exercise Price Per Share, Beginning Balance	$ 8.23	$ 5.87	$ 2.89
Weighted Average Exercise Price Per Share, Granted	16.35	15.12	11.54
Weighted Average Exercise Price Per Share, Exercised	6.82	1.97	1.47
Weighted Average Exercise Price Per Share, Canceled/Forfeited	11.42	7.19	4.31
Weighted Average Exercise Price Per Share, Ending Balance	10.27	$ 8.23	$ 5.87	$ 2.89
Weighted Average Exercise Price Per Share, Vested and expected to vest	10.26
Weighted Average Exercise Price Per Share, Exercisable	$ 7.40
Weighted-Average Contractual Term
Weighted-Average Contractual Term	6 years 2 months 12 days	7 years 2 months 12 days	7 years 8 months 12 days	7 years 2 months 12 days
Weighted-Average Contractual Term, Vested and expected to vest	6 years 2 months 12 days
Weighted-Average Contractual Term, Exercisable	6 years
Aggregate Intrinsic Value
Aggregate Intrinsic Value, Outstanding	$ 107,091	$ 61,367	$ 139,484	$ 40,705
Aggregate Intrinsic Value, Vested and expected to vest	106,197
Aggregate Intrinsic Value, Exercisable	$ 76,843

Share-Based Compensation - Tota

Share-Based Compensation - Total Intrinsic Values of Options Exercised (Detail) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2015	Dec. 31, 2014	Dec. 31, 2013
Disclosure Of Compensation Related Costs Sharebased Payments [Abstract]
Total intrinsic value of options exercised	$ 28,336	$ 41,454	$ 10,261

Share-Based Compensation - Weig

Share-Based Compensation - Weighted Average Assumptions Used to Fair Value of Stock Options Granted (Detail) - $ / shares	12 Months Ended
	Dec. 31, 2015	Dec. 31, 2014	Dec. 31, 2013
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Expected volatility	48.00%	48.00%	54.00%
Risk-free interest rate	1.22%	1.41%	1.68%
Expected dividend yield	0.00%	0.00%	0.00%
Options
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Expected term (in years)	4 years 9 months 18 days	4 years 7 months 6 days	6 years 1 month 6 days
Grant date fair value of employee options	$ 6.78	$ 6.16	$ 6.19
Non Employee Stock Option
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Expected term (in years)	7 years	7 years	10 years

Share-Based Compensation - Su68

Share-Based Compensation - Summary of Assumptions Used to Value ESPP Rights Under the Black-Scholes Option-Pricing Model (Detail) - $ / shares	12 Months Ended
	Dec. 31, 2015	Dec. 31, 2014	Dec. 31, 2013
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Expected volatility	48.00%	48.00%	54.00%
Risk-free interest rate	1.22%	1.41%	1.68%
Expected dividend yield	0.00%	0.00%	0.00%
2013 Employee stock purchase plan
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Expected term (in years)	6 months	6 months
Expected volatility	42.00%	50.00%
Risk-free interest rate	0.25%	0.07%
Expected dividend yield	0.00%	0.00%
Offering grant date fair value of ESPP rights	$ 5.05	$ 3.93

Share-Based Compensation - Su69

Share-Based Compensation - Summary of RSUs Activity (Detail) - Restricted Stock Units - USD ($) $ / shares in Units, shares in Thousands, $ in Thousands	12 Months Ended
	Dec. 31, 2015	Dec. 31, 2014	Dec. 31, 2013
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Number of RSUs Outstanding, Beginning Balance	1,739	68
Number of RSUs Outstanding, Granted	1,365	1,915
Number of RSUs Outstanding, Released	(571)	(110)
Number of RSUs Outstanding, Canceled/Forfeited	(245)	(134)
Number of RSUs Outstanding, Ending Balance	2,288	1,739
Weighted Average Grant Date Fair Value Per Share, Beginning Balance	$ 14.87	$ 17.22
Weighted Average Grant Date Fair Value Per Share, Granted	18.09	15.08
Weighted Average Grant Date Fair Value Per Share, Released	15.45	16.82
Weighted Average Grant Date Fair Value Per Share, Canceled/Forfeited	15.10	17.43
Weighted Average Grant Date Fair Value Per Share, Ending Balance	$ 16.63	$ 14.87
Aggregate Intrinsic Value, Outstanding	$ 53,972	$ 25,617	$ 1,251

Income Taxes - Summary of Provi

Income Taxes - Summary of Provision (Benefit) from Continuing Operations on Basis of Segment Reporting (Detail) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2015	Dec. 31, 2014	Dec. 31, 2013
Current:
State	$ 71	$ 18	$ 3
Foreign	85	114	(32)
Total current	156	132	(29)
Deferred:
Federal	(1,312)
State	(99)
Foreign	(8)	(35)	(16)
Total deferred	(1,419)	(35)	(16)
Total income tax provision (benefit)	$ (1,263)	$ 97	$ (45)

Income Taxes - Summary of Incom

Income Taxes - Summary of Income from Continuing Operations Before Income Taxes on Basis of Segment Reporting (Detail) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2015	Dec. 31, 2014	Dec. 31, 2013
Income Tax Disclosure [Abstract]
United States	$ (28,870)	$ (50,065)	$ (41,778)
International	(4,492)	1,822	(4,365)
Loss before provision (benefit) for income taxes	$ (33,362)	$ (48,243)	$ (46,143)

Income Taxes - Additional Infor

Income Taxes - Additional Information (Detail) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2015	Dec. 31, 2014	Dec. 31, 2013
Income Taxes [Line Items]
Statutory federal income tax rate	34.00%
Benefit for income taxes from release of valuation allowance	$ 1,411
Expected increase in equity if certain deferred tax assets are realized	$ 14,400
Net operating loss carry-forwards for federal income tax, expiration period	2,023
Net operating loss carry-forwards for state income tax, expiration period	2,015
Limitations in use of net operating losses	Events which may cause limitations in the amount of the net operating losses that the Company may use in any one year include, but are not limited to, a cumulative ownership change of more than 50% over a three-year period.
Period for cumulative ownership change	3 years
Valuation allowances, deferred tax asset, increase	$ 11,100	$ 16,400	$ 15,200
Federal
Income Taxes [Line Items]
Net operating loss carry-forwards	$ 170,200	140,100
Research credit carry-forwards for tax purposes, expiration period	2,028
California
Income Taxes [Line Items]
Net operating loss carry-forwards	$ 117,000	102,400
Minimum
Income Taxes [Line Items]
Cumulative ownership change percentage	50.00%
Research credit carry-forward | Federal
Income Taxes [Line Items]
Research credit carry-forwards for tax purposes	$ 3,600	2,800
Research credit carry-forward | California
Income Taxes [Line Items]
Research credit carry-forwards for tax purposes	$ 4,000	$ 2,800

Income Taxes - Summary of Varia

Income Taxes - Summary of Variation of Effective Provision (Benefit) for Income Taxes from Statutory Federal Income Tax Rate (Detail) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2015	Dec. 31, 2014	Dec. 31, 2013
Income Tax Disclosure [Abstract]
Federal tax benefit at statutory rate	$ (11,343)	$ (16,403)	$ (15,687)
State tax, net of federal provision (benefit)	(34)	12	2
Research and development credits	(667)	(654)	(774)
Share-based compensation	1,086	1,836	641
Other permanent differences	325	211	294
Foreign tax rate differential	(80)	(33)	(20)
Net operating losses not recognized	10,762	15,128	15,499
Release of valuation allowance associated with acquisitions	(1,312)
Total income tax provision (benefit)	$ (1,263)	$ 97	$ (45)

Income Taxes - Schedule of Defe

Income Taxes - Schedule of Deferred Income Tax Assets and Liabilities (Detail) - USD ($) $ in Thousands	Dec. 31, 2015	Dec. 31, 2014	Dec. 31, 2013
Deferred tax assets
Net operating loss and credit carry-forwards	$ 54,858	$ 45,552	$ 35,904
Research and development credits	4,712	3,497	2,353
Sales tax liability	1,337	1,442	1,418
Share-based compensation	6,694	5,560	2,247
Accrued liabilities	6,090	4,676	2,528
Gross deferred tax assets	73,691	60,727	44,450
Valuation allowance	(71,514)	(60,405)	(44,032)
Total deferred tax assets	2,177	322	418
Deferred tax liabilities - Acquired intangibles	(1,164)
Deferred tax liabilities - Property and equipment	(883)	(197)	(327)
Net deferred tax assets	$ 130	$ 125	$ 91

Income Taxes - Summary of Recon

Income Taxes - Summary of Reconciliation of Beginning and Ending Amount of Unrecognized Tax Benefits (Detail) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2015	Dec. 31, 2014
Reconciliation Of Unrecognized Tax Benefits Excluding Amounts Pertaining To Examined Tax Returns Roll Forward
Beginning balance	$ 2,615	$ 933
Gross amount of increases in unrecognized tax benefits for tax positions taken in current year	499	465
Gross amount of increases in unrecognized tax benefits for tax positions taken in prior year		1,217
Gross amount of decreases in unrecognized tax benefits for tax positions	(1,217)
Ending balance	$ 1,897	$ 2,615

Basic and Diluted Net Loss Pe76

Basic and Diluted Net Loss Per Share - Computation of Company's Basic and Diluted Net Loss Per Share of Common Stock (Detail) - USD ($) $ / shares in Units, shares in Thousands, $ in Thousands	3 Months Ended								12 Months Ended
	Dec. 31, 2015	Sep. 30, 2015	Jun. 30, 2015	Mar. 31, 2015	Dec. 31, 2014	Sep. 30, 2014	Jun. 30, 2014	Mar. 31, 2014	Dec. 31, 2015	Dec. 31, 2014	Dec. 31, 2013
Numerator
Net loss	$ (6,941)	$ (6,336)	$ (8,211)	$ (10,611)	$ (10,120)	$ (11,986)	$ (13,330)	$ (12,904)	$ (32,099)	$ (48,340)	$ (46,098)
Denominator
Weighted-average common shares for basic and diluted net loss per share									70,069	66,818	33,155
Basic and diluted net loss per share	$ (0.10)	$ (0.09)	$ (0.12)	$ (0.15)	$ (0.15)	$ (0.18)	$ (0.20)	$ (0.20)	$ (0.46)	$ (0.72)	$ (1.39)

Basic and Diluted Net Loss Pe77

Basic and Diluted Net Loss Per Share - Potential Shares of Common Stock Excluded from Diluted Weighted-Average Common Shares Outstanding (Detail) - shares shares in Thousands	12 Months Ended
	Dec. 31, 2015	Dec. 31, 2014	Dec. 31, 2013
Antidilutive Securities Excluded From Computation Of Earnings Per Share [Line Items]
Potential common shares excluded from diluted net loss per share	10,339	10,912	11,763
Conversion Of Warrants
Antidilutive Securities Excluded From Computation Of Earnings Per Share [Line Items]
Potential common shares excluded from diluted net loss per share			502
Repurchase Common Stock
Antidilutive Securities Excluded From Computation Of Earnings Per Share [Line Items]
Potential common shares excluded from diluted net loss per share	2	15	37
Equity Incentive Plans
Antidilutive Securities Excluded From Computation Of Earnings Per Share [Line Items]
Potential common shares excluded from diluted net loss per share	10,337	10,897	11,224

Geographic Concentrations - Add

Geographic Concentrations - Additional Information (Detail) - Geographic Concentration Risk - Country	12 Months Ended
	Dec. 31, 2015	Dec. 31, 2014	Dec. 31, 2013
Non-US [Member] | Sales Revenue, Segment
Concentration Risk [Line Items]
Number of foreign countries representing more than ten percent	0	0	0
Non-US [Member] | Property, Plant and Equipment
Concentration Risk [Line Items]
Number of foreign countries representing more than ten percent	0	0
Minimum | United States | Sales Revenue, Segment
Concentration Risk [Line Items]
Concentration risk	90.00%	90.00%	90.00%
Minimum | United States | Property, Plant and Equipment
Concentration Risk [Line Items]
Concentration risk	86.00%	87.00%

Selected Quarterly Financial 79

Selected Quarterly Financial Data (Unaudited) - Selected Unaudited Quarterly Consolidated Statements of Operations Data (Detail) - USD ($) $ / shares in Units, $ in Thousands	3 Months Ended								12 Months Ended
	Dec. 31, 2015	Sep. 30, 2015	Jun. 30, 2015	Mar. 31, 2015	Dec. 31, 2014	Sep. 30, 2014	Jun. 30, 2014	Mar. 31, 2014	Dec. 31, 2015	Dec. 31, 2014	Dec. 31, 2013
Consolidated Statements of Operations Data:
Revenues	$ 83,439	$ 76,780	$ 70,691	$ 65,318	$ 61,893	$ 56,944	$ 52,787	$ 48,262	$ 296,228	$ 219,887	$ 160,505
Gross profit	60,577	54,447	49,162	44,771	41,972	37,539	33,244	30,359	208,957	143,114	98,986
Operating loss	(5,996)	(5,828)	(9,539)	(9,569)	(9,343)	(10,814)	(12,810)	(12,238)	(30,932)	(45,205)	(41,033)
Net loss	$ (6,941)	$ (6,336)	$ (8,211)	$ (10,611)	$ (10,120)	$ (11,986)	$ (13,330)	$ (12,904)	$ (32,099)	$ (48,340)	$ (46,098)
Basic and diluted net loss per share	$ (0.10)	$ (0.09)	$ (0.12)	$ (0.15)	$ (0.15)	$ (0.18)	$ (0.20)	$ (0.20)	$ (0.46)	$ (0.72)	$ (1.39)

Related-Party Transactions - Ad

Related-Party Transactions - Additional Information (Detail) - Alphabet Inc. - USD ($) $ in Millions	12 Months Ended
	Dec. 31, 2015	Dec. 31, 2014	Dec. 31, 2013
Related Party Transaction [Line Items]
Total payables to related party	$ 2	$ 0.9
Total expenses incurred from related party	$ 11.9	$ 10.1	$ 10.7