RingCentral (RNG) 10-Q 10 May 18 2018 Q1 Quarterly report Financial data

Document and Entity Information

Document and Entity Information - shares	3 Months Ended
	Mar. 31, 2018	May 04, 2018
Document And Entity Information [Line Items]
Document Type	10-Q
Amendment Flag	false
Document Period End Date	Mar. 31, 2018
Document Fiscal Year Focus	2,018
Document Fiscal Period Focus	Q1
Trading Symbol	RNG
Entity Registrant Name	RingCentral Inc
Entity Central Index Key	1,384,905
Current Fiscal Year End Date	--12-31
Entity Filer Category	Large Accelerated Filer
Class A common stock
Document And Entity Information [Line Items]
Entity Common Stock, Shares Outstanding		66,807,773
Class B common stock
Document And Entity Information [Line Items]
Entity Common Stock, Shares Outstanding		11,904,332

CONDENSED CONSOLIDATED BALANCE

CONDENSED CONSOLIDATED BALANCE SHEETS (Unaudited) - USD ($) $ in Thousands	Mar. 31, 2018	Dec. 31, 2017
Current assets
Cash and cash equivalents	$ 554,963	$ 181,192
Accounts receivable, net	55,379	46,690
Deferred sales commission costs	16,649	15,424
Prepaid expenses and other current assets	24,118	21,512
Total current assets	651,109	264,818
Property and equipment, net	50,131	43,298
Deferred sales commission costs, noncurrent	40,140	37,871
Goodwill	9,393	9,393
Acquired intangibles, net	22,377	1,462
Other assets	2,328	2,972
Total assets	775,478	359,814
Current liabilities
Accounts payable	4,256	7,322
Accrued liabilities	64,562	54,977
Current portion of capital lease obligation	1,252
Deferred revenue	68,037	62,917
Total current liabilities	138,107	125,216
Convertible senior notes, net	352,004
Capital lease obligation	3,261
Other long-term liabilities	6,240	6,252
Total liabilities	499,612	131,468
Commitments and contingencies (Note 8)
Stockholders' equity
Common stock	8	8
Additional paid-in capital	484,854	434,840
Accumulated other comprehensive income	3,220	2,998
Accumulated deficit	(212,216)	(209,500)
Total stockholders' equity	275,866	228,346
Total liabilities and stockholders' equity	$ 775,478	$ 359,814

CONDENSED CONSOLIDATED STATEMEN

CONDENSED CONSOLIDATED STATEMENTS OF OPERATIONS (Unaudited) - USD ($) shares in Thousands	3 Months Ended
	Mar. 31, 2018	Mar. 31, 2017
Revenues
Software subscriptions	$ 136,960,000	$ 104,130,000
Other	13,383,000	8,104,000
Total revenues	150,343,000	112,234,000
Cost of revenues
Software subscriptions	24,526,000	20,263,000
Other	11,148,000	7,043,000
Total cost of revenues	35,674,000	27,306,000
Gross profit	114,669,000	84,928,000
Operating expenses
Research and development	22,651,000	17,087,000
Sales and marketing	71,920,000	54,265,000
General and administrative	21,449,000	15,805,000
Total operating expenses	116,020,000	87,157,000
Loss from operations	(1,351,000)	(2,229,000)
Other income (expense), net
Interest expense	(1,411,000)	(79,000)
Other income, net	73,000	122,000
Other income (expense), net	(1,338,000)	43,000
Loss before income taxes	(2,689,000)	(2,186,000)
Provision for income taxes	27,000	51,000
Net loss	$ (2,716,000)	$ (2,237,000)
Net loss per common share
Basic and diluted	$ (0.03)	$ (0.03)
Weighted-average number of shares used in computing net loss per share
Basic and diluted	78,341	74,682

CONDENSED CONSOLIDATED STATEME4

CONDENSED CONSOLIDATED STATEMENTS OF COMPREHENSIVE LOSS (Unaudited) - USD ($) $ in Thousands	3 Months Ended
	Mar. 31, 2018	Mar. 31, 2017
Statement Of Income And Comprehensive Income [Abstract]
Net loss	$ (2,716)	$ (2,237)
Other comprehensive loss
Foreign currency translation adjustments	222	31
Comprehensive loss	$ (2,494)	$ (2,206)

CONDENSED CONSOLIDATED STATEME5

CONDENSED CONSOLIDATED STATEMENTS OF CASH FLOWS (Unaudited) - USD ($) $ in Thousands	3 Months Ended
	Mar. 31, 2018	Mar. 31, 2017
Cash flows from operating activities
Net loss	$ (2,716)	$ (2,237)
Adjustments to reconcile net loss to net cash provided by operating activities:
Depreciation and amortization	5,542	3,785
Share-based compensation	13,267	8,935
Amortization of deferred sales commission costs	3,984	2,597
Amortization of debt discount and issuance costs	1,370
Foreign currency remeasurement (gain) loss	267	(44)
Provision for bad debt	554	289
Deferred income taxes	(6)	(2)
Other	206	98
Changes in assets and liabilities:
Accounts receivable	(9,243)	(1,594)
Deferred sales commission costs	(7,478)	(7,226)
Prepaid expenses and other current assets	(2,270)	(2,038)
Other assets	337	45
Accounts payable	(2,816)	(2,224)
Accrued liabilities	6,079	4,159
Deferred revenue	5,120	3,989
Other liabilities	(12)	178
Net cash provided by operating activities	12,185	8,710
Cash flows from investing activities
Purchases of property and equipment	(4,587)	(5,155)
Capitalized internal-use software	(2,759)	(1,640)
Cash paid for acquisition of intangible assets	(18,470)
Net cash used in investing activities	(25,816)	(6,795)
Cash flows from financing activities
Proceeds from issuance of convertible senior notes, net of issuance costs	449,457
Payments for capped call transactions and costs	(49,910)
Repurchase of common stock	(15,000)
Proceeds from issuance of stock in connection with stock plans	3,688	2,679
Taxes paid related to net share settlement of equity awards	(1,014)	(221)
Repayment of debt		(14,840)
Repayment of capital lease obligations		(181)
Net cash provided by (used in) financing activities	387,221	(12,563)
Effect of exchange rate changes	181	(17)
Net increase (decrease) in cash, cash equivalents and restricted cash	373,771	(10,665)
Cash, cash equivalents and restricted cash
Beginning of period	181,192	160,355
End of period	554,963	149,690
Supplemental disclosure of cash flow data
Cash paid for interest		116
Cash paid for income taxes, net of refunds	44	83
Non-cash investing and financing activities
Equipment acquired under capital lease	4,513
Contingent consideration not paid relating to asset acquisition	3,848
Equipment and capitalized internal-use software purchased and unpaid at period end	$ 1,108	757
Glip, Inc.
Non-cash investing and financing activities
Issuance of common stock for business combination		$ 200

Description of Business and Sum

Description of Business and Summary of Significant Accounting Policies	3 Months Ended
	Mar. 31, 2018
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 and collaboration. The Company was incorporated in California in 1999 and was reincorporated in Delaware on September 26, 2013. Basis of Presentation and Consolidation The unaudited condensed consolidated financial statements and accompanying notes of the Company reflect all adjustments (all of which are normal, recurring in nature and those discussed in these notes) that are, in the opinion of management, necessary for a fair presentation of the interim periods presented. All intercompany balances and transactions have been eliminated in consolidation. The results of operations for the interim periods presented are not necessarily indicative of the results to be expected for any subsequent quarter or for the entire year ending December 31, 2018. Certain information and note disclosures normally included in annual consolidated financial statements prepared in accordance with generally accepted accounting principles in the United States of America (“U.S. GAAP”) have been condensed or omitted under the rules and regulations of the Securities and Exchange Commission (“SEC”). Effective January 1, 2018, the Company adopted the requirements of Accounting Standards Update (“ASU”) No. 2014-09, Revenue from Contracts with Customers (Topic 606) the Financial Accounting Standards Board (“FASB”), Other Assets and Deferred Costs - Contracts with Customers The unaudited condensed consolidated financial statements should be read in conjunction with the Company’s audited consolidated financial statements and related notes included in the Company’s Annual Report on Form 10-K for the year ended December 31, 2017, Use of Estimates The preparation of condensed consolidated financial statements in conformity with U.S. GAAP requires management to make estimates and assumptions that affect the reported amounts of assets and liabilities, disclosure of contingent assets and liabilities at the date of the condensed consolidated financial statements, and the reported amounts of revenues and expenses during the reporting period. The significant estimates made by management affect revenues, the allowance for doubtful accounts, deferred sales commission costs, goodwill, share-based compensation, capitalization of internally developed software, return reserves, provision for income taxes, uncertain tax positions, loss contingencies, sales tax liabilities, and accrued liabilities. Management periodically evaluates these estimates and will make adjustments prospectively based upon the results of such periodic evaluations. Actual results could differ from these estimates. Changes in Significant Accounting Policies Except for the accounting policies for revenue recognition and deferred commissions that were updated as a result of adopting Topic 606, there have been no changes to our significant accounting policies described in the Annual Report on Form 10-K for the year ended December 31, 2017, that have had a material impact on the Company’s condensed consolidated financial statements and related notes. Revenue Recognition The Company derives its revenues primarily from software subscriptions, sale of products, and professional services. Revenues are recognized when control of these services is transferred to the customers, in an amount that reflects the consideration the Company expects to be entitled to in exchange for those services. The Company determines revenue recognition through the following steps: • identification of the contract or the contracts, with a customer; • identification of the performance obligations in the contract; • determination of the transaction price; • allocation of the transaction price to the performance obligations in the contract; and • recognition of revenue when, or as, the Company satisfies a performance obligation. The Company recognizes revenues as follows: Software subscriptions revenue Software subscriptions revenue is generated from the sale of subscriptions to the Company’s software applications and related services, which have contractual terms typically ranging from one month to five years, and include recurring fixed plan subscription fees and variable usage-based fees for usage in excess of plan limits. Arrangements with customers do not provide the customer with the right to take possession of the Company’s software at any time. Instead, customers are granted continuous access to the services over the contractual period. The Company transfers control evenly over the contractual period by providing stand-ready service. Accordingly, the fixed consideration related to subscription is generally recognized over time on a straight-line basis over the contract term beginning on the date the Company’s service is made available to the customer. The Company may offer its customer services for no consideration during the initial months. Such discounts are recognized ratably over the term of the contract. Fees for additional minutes of usage in excess of plan limits are deemed to be variable consideration that meet the allocation exception for variable consideration as they are specific to the month that the usage occurs. The Company’s subscription contracts typically allow the customers to terminate their services within the first 30 or 60 days and receive a refund for any amounts paid. After the termination period ends, the contract is non-cancellable and the customer is obligated to pay for the remaining term of the contract. Accordingly, the Company considers the non-cancellable term of the contract to begin after the expiration of the termination period. The Company has service-level agreements with customers warranting defined levels of uptime reliability and performance and these customers can get credits or refunds if the Company fails to meet those levels. If the services do not meet certain criteria, fees are subject to adjustment or refund representing a form of variable consideration. 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 the Company’s historical experience, current trends and the Company’s expectations regarding future experience. The Company monitors the accuracy of its sales reserve estimates by reviewing actual returns and credits and adjusts them for its future expectations to determine the adequacy of its current and future reserve needs. If actual future returns and credits differ from past experience, additional reserves may be required. Other revenue Other revenue is generated from product revenues from sales of phones and professional implementation services. Product revenue is recognized when the products have been delivered to the customer. The amount of revenue recognized for products is adjusted for expected returns, which are estimated based on historical data. The Company offers professional services that support implementation and deployment of its subscription services. Professional services do not result in significant customization of the product and are generally short-term in duration. The majority of our professional services contracts are on a fixed price basis and revenue is recognized over time as services are performed. Deferred sales commission costs The Company capitalizes sales commission expenses and associated payroll taxes paid to internal sales personnel, value added resellers and channel partners that are incremental to obtaining customer contracts. These costs are deferred and then amortized over the expected period of benefit, which is estimated to be five years. The Company has determined the period of benefit taking into consideration the expected subscription term and expected renewals of its customer contracts, the duration of its relationships with its customers, its technology and other factors. Amortization expense is included in sales and marketing expenses in the accompanying condensed consolidated statement of operations. Disaggregation of revenue The following table provides information about disaggregated revenue by primary geographical markets: Three Months Ended March 31, 2018 2017 Primary geographical markets North America 95.9 % 97.1 % Others 4.1 2.9 Total revenues 100.0 % 100.0 % The Company derived approximately 86.1% and 82.9% of subscription revenues from RingCentral Office product for the three months ended March 31, 2018 and 2017, respectively. Deferred revenue During the first quarter of 2018 the Company recognized revenue of $33.7 million that was included in the corresponding deferred revenue balance at the beginning of the period. Remaining performance obligations The typical subscription term ranges from one month to five years. Contract revenue as of March 31, 2018, that has not yet been recognized was $424 million. This excludes contracts with an original expected length of less than one year. The Company expects to recognize revenue of $269 million over the next 12 months and $155 million thereafter. Share-Based Compensation Share-based compensation expense resulting from options, restricted stock units (“RSUs”), performance-based awards, and employee stock purchase plan (“ESPP”) rights granted is measured as the grant date fair value of the award and is recognized using the straight-line attribution method over the requisite service period of the award, which is generally the vesting period. The Company estimates the fair value of stock options, ESPP rights, and performance based awards using the Black-Scholes-Merton option-pricing model. The Company estimates the fair value of RSUs as the closing market value of its Class A Common Stock on the grant date. For awards with performance-based and service-based conditions, compensation cost is recognized over the requisite service period if it is probable that the performance condition will be satisfied. The expense for performance-based awards is evaluated each quarter based on the achievement of the performance conditions. The effect of a change in the estimated number of performance based awards expected to be earned is recognized in the period those estimates are revised. Compensation expense for stock options and RSUs granted to non-employees is revalued, or marked to market, as of each reporting date until the stock options and RSUs are vested. Compensation expense is recognized net of estimated forfeiture activity, which is based on historical forfeiture rates. Recent Accounting Pronouncements Not Yet Adopted In February 2016, the FASB issued ASU 2016-02, Leases (Topic 842) In January 2017, the FASB issued ASU 2017-04, Simplifying the Test for Goodwill Impairment In February 2018, the FASB issues ASU 2018-03, Technical Corrections and Improvements to Financial Statements – Overall (Sub Topic 825-10) – Recognition and Measurement of Financial Assets and Financial Liabilities Financial Instruments-Overall: Recognition and Measurement of Financial Assets and Liabilities

Impact of Recent Accounting Pro

Impact of Recent Accounting Pronouncements	3 Months Ended
	Mar. 31, 2018
New Accounting Pronouncements And Changes In Accounting Principles [Abstract]
Impact of Recent Accounting Pronouncements	Note 2. Impact of Recent Accounting Pronouncements On January 1, 2018, the Company adopted Topic 606 utilizing the full retrospective method of transition. The Company adjusted its condensed consolidated financial statements from amounts previously reported due to the adoption of Topic 606. Select condensed consolidated balance sheet line items, which reflect the adoption of the new ASU are as follows (in thousands): December 31, 2017 As Reported Adoption of Topic 606 As Adjusted Assets Accounts receivable, net $ 45,339 $ 1,351 $ 46,690 Deferred sales commission costs — 15,424 15,424 Deferred sales commission costs, noncurrent — 37,871 37,871 Liabilities Deferred revenue 64,415 (1,498 ) 62,917 Stockholders' equity $ 172,202 $ 56,144 $ 228,346 The following table reflects the effect of adoption of Topic 606 on the Company’s condensed consolidated statement of operations for the three months ended March 31, 2017 (in thousands): Three Months Ended March 31, 2017 As Reported Adoption of Topic 606 As Adjusted Revenues Software subscriptions $ 103,687 $ 443 $ 104,130 Other 8,104 — 8,104 Total revenues 111,791 443 112,234 Gross profit 84,485 443 84,928 Operating expenses Sales and marketing 58,894 (4,629 ) 54,265 Operating loss (7,301 ) 5,072 (2,229 ) Net loss $ (7,309 ) $ 5,072 $ (2,237 ) Basic and diluted Net loss per Common Share $ (0.10 ) $ 0.07 $ (0.03 ) Weighted-average number of shares used in computing net loss per share Basic and diluted 74,682 — 74,682 The following table reflects the effect of adoption of Topic 606 on the Company’s condensed consolidated statement of cash flows for the three months ended March 31, 2017 (in thousands): Three Months Ended March 31, 2017 As Reported Adoption of Topic 606 As Adjusted Cash flows from operating activities Net loss $ (7,309 ) $ 5,072 $ (2,237 ) Adjustments to reconcile net loss to net cash provided by operating activities: Amortization of deferred sales commission costs — 2,597 2,597 Changes in operating assets and liabilities: Accounts receivable (1,371 ) (223 ) (1,594 ) Deferred sales commission costs — (7,226 ) (7,226 ) Deferred revenue 4,209 (220 ) 3,989 Net cash provided by operating activities 8,710 — 8,710

Other Revenue and Cost of Reven

Other Revenue and Cost of Revenue	3 Months Ended
	Mar. 31, 2018
Organization Consolidation And Presentation Of Financial Statements [Abstract]
Other Revenue and Cost of Revenue	Note 3. Other Revenue and Cost of Revenue Other revenues are primarily comprised of product revenue from the sale of pre-configured phones, phone rentals, and professional services. For the three months ended March 31, 2018 and 2017, the majority of other revenues consisted of product revenues from sales of phones. Product revenues were $8.0 million and $6.1 million for the three months ended March 31, 2018 and 2017, respectively. Product cost of revenues were $7.2 million and $5.9 million for the three months ended March 31, 2018 and 2017, respectively.

Financial Statement Components

Financial Statement Components	3 Months Ended
	Mar. 31, 2018
Organization Consolidation And Presentation Of Financial Statements [Abstract]
Financial Statement Components	Note 4. Financial Statement Components Cash and cash equivalents consisted of the following (in thousands): March 31, December 31, 2018 2017 Cash $ 44,133 $ 70,893 Money market funds 510,830 110,299 Total cash and cash equivalents $ 554,963 $ 181,192 The Company has an immaterial restricted cash balance as of March 31, 2018 and December 31, 2017, included in the cash balance above. Accounts receivable, net consisted of the following (in thousands): March 31, December 31, 2018 2017 As Adjusted Accounts receivable $ 48,227 $ 42,243 Unbilled accounts receivable 8,189 5,159 Allowance for doubtful accounts (1,037 ) (712 ) Accounts receivable, net $ 55,379 $ 46,690 Prepaid expenses and other current assets consisted of the following (in thousands): March 31, December 31, 2018 2017 Prepaid expenses $ 17,076 $ 13,690 Inventory 229 198 Other current assets 6,813 7,624 Total prepaid expenses and other current assets $ 24,118 $ 21,512 Property and equipment, net consisted of the following (in thousands): March 31, December 31, 2018 2017 Computer hardware and software $ 80,626 $ 74,555 Internal-use software development costs 20,867 18,217 Furniture and fixtures 6,314 6,293 Leasehold improvements 5,249 4,311 Total property and equipment 113,056 103,376 Less: accumulated depreciation and amortization (62,925 ) (60,078 ) Property and equipment, net $ 50,131 $ 43,298 Depreciation and amortization expense was $4.5 million and $3.5 million for the three months ended March 31, 2018 and 2017, respectively. Accrued liabilities consisted of the following (in thousands): March 31, December 31, 2018 2017 Accrued compensation and benefits $ 16,401 $ 18,578 Accrued sales, use and telecom related taxes 13,366 11,828 Accrued marketing 9,943 7,020 Other accrued expenses 24,852 17,551 Total accrued liabilities $ 64,562 $ 54,977 The carrying values of intangible assets are as follows (in thousands): March 31, 2018 December 31, 2017 Estimated Lives Cost Accumulated Amortization Acquired Intangibles, Net Cost Accumulated Amortization Acquired Intangibles, Net Customer relationships 2 to 5 years $ 22,822 $ 1,756 $ 21,066 $ 840 $ 840 $ - Developed technology 5 years 3,010 1,699 1,311 3,010 1,548 1,462 Total acquired intangible assets $ 25,832 $ 3,455 $ 22,377 $ 3,850 $ 2,388 $ 1,462 During the three months ended March 31, 2018, the Company acquired $22.0 million of customer relationships. See Note 6. Amortization expense from acquired intangible assets for the three months ended March 31, 2018 and 2017 was $1.1 million and $0.3 million, respectively. Amortization of developed technology is included in cost of revenues and amortization of customer relationships is included in sales and marketing expenses in the condensed consolidated statements of operations. At March 31, 2018, the weighted average amortization period for customer relationships and developed technology was approximately 4.8 years and 2.2 years, respectively. Estimated amortization expense for acquired intangible assets for the following five fiscal years and thereafter is as follows (in thousands): 2018 (remaining) $ 3,749 2019 4,998 2020 4,654 2021 4,396 2022 onwards 4,580 Total estimated amortization expense $ 22,377 Deferred Sales Commission Costs Deferred sales commission costs, which relate to sales commission costs capitalized for incremental cost of obtaining customer contracts, were $56.8 million and $53.3 million as of March 31, 2018 and December 31, 2017, respectively. Amortization expense for the deferred sales commission costs for the three months ended March 31, 2018 and 2017 were $4.0 million and $2.6 million, respectively. There was no impairment loss in relation to the costs capitalized for the periods presented.

Fair Value of Financial Instrum

Fair Value of Financial Instruments	3 Months Ended
	Mar. 31, 2018
Fair Value Disclosures [Abstract]
Fair Value of Financial Instruments	Note 5. Fair Value of Financial Instruments 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. The Company measures and reports certain cash equivalents, including money market funds and certificates of deposit, at fair value in accordance with the provisions of the authoritative accounting guidance that addresses fair value measurements. This guidance establishes a hierarchy for inputs used in measuring fair value that maximizes the use of observable inputs and minimizes the use of unobservable inputs by requiring that the most observable inputs be used when available. The hierarchy is broken down into three levels based on the reliability of the inputs as follows: Level 1: Valuations based on observable inputs that reflect unadjusted quoted prices in active markets for identical assets or liabilities. Level 2: Valuations based on 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: Valuations based on 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 techniques. The financial assets carried at fair value were determined using the following inputs (in thousands): Balance at March 31, 2018 (Level 1) (Level 2) (Level 3) Cash equivalents: Money market funds $ 510,830 $ 510,830 $ — $ — Balance at December 31, 2017 (Level 1) (Level 2) (Level 3) Cash equivalents: Money market funds $ 110,299 $ 110,299 $ — $ — The As of March 31, 2018, the fair value of the 0% convertible senior notes due 2023 (the “Notes”) (described in Note 7 below) was approximately $463.8 million. The fair value was determined based on the quoted price for the Notes in an inactive market on the last trading day of the reporting period and is considered as Level 2 in the fair value hierarchy.

Customer Base Acquisition

Customer Base Acquisition	3 Months Ended
	Mar. 31, 2018
Business Combinations [Abstract]
Customer Base Acquisition	Note 6. Customer Base Acquisition On January 16, 2018, the Company acquired from AT&T, Inc. (“AT&T”) the existing customer base of the RingCentral Office Hand solution, for which AT&T acted as a reseller, for a total purchase consideration of up to $26.0 million. The purchase price consisted of a $20.0 million cash payment upon closing of the transaction and up to $6.0 million in earn-out payments based on achievement of certain milestones. The transition of the customer base is expected to be completed over a period of one year from the close of the transaction. The Company has entered into a Transition Services Agreement (“TSA”) for a period of one year for the transition of these customers. The total purchase consideration was estimated to be $24.1 million upon the close of the transaction, consisting of $20.2 million cash payments, including transaction costs, and $3.8 million earn-out consideration. The transaction is accounted for as an asset acquisition. The value of the total consideration was allocated between the customer relationship intangible asset and the TSA services based on their relative fair value. As of March 31, 2018, the amount allocated to the customer relationship intangible asset was approximately $22.0 million and will be amortized over the expected useful life of five years. The value allocated to the TSA was $2.1 million and will be amortized over a period of one year which is the period in which customers will be transitioned. The following table summarizes the fair value of assets acquired as of the date of acquisition (in thousands): Fair Value Estimated Useful Life Customer relationships $ 21,982 5 years Transition Services Agreement 2,082 1 year Net assets acquired $ 24,064

Convertible Senior Notes

Convertible Senior Notes	3 Months Ended
	Mar. 31, 2018
Debt Disclosure [Abstract]
Convertible Senior Notes	Note 7. Convertible Senior Notes In March 2018, the Company issued $400.0 million aggregate principal amount of 0% convertible senior notes due 2023 in a private placement and an additional $60.0 million aggregate principal amount of such notes pursuant to the exercise in full of the over-allotment options of the initial purchasers. The Notes do not bear regular interest, and the principal amount of the Notes does not accrete. The Notes may bear special interest under specified circumstances relating to the Company’s failure to comply with its reporting obligations under the indenture relating to the issuance of Notes (the “Indenture”) or if the Notes are not freely tradeable as required by the indenture. The Notes will mature on March 15, 2023, unless earlier repurchased or redeemed by the Company or converted pursuant to their terms. The total net proceeds from the debt offering, after deducting initial purchase discounts and debt issuance costs, were approximately $449.5 million. Each $1,000 principal amount of the Notes is initially convertible into 12.2782 shares of the Company’s Class A common stock par value $0.0001 (“Class A Common Stock”), which is equivalent to an initial conversion price of approximately $81.45 per share. The conversion rate is subject to adjustment upon the occurrence of certain specified events but will not be adjusted for any accrued and unpaid special interest. In addition, upon the occurrence of a make-whole fundamental change or a redemption period, each as defined in the Indenture, the Company will, in certain circumstances, increase the conversion rate by a number of additional shares for a holder that elects to convert its Notes in connection with such make-whole fundamental change or during the relevant redemption period. Prior to the close of business on the business day immediately preceding December 15, 2022, the Notes will be convertible only under the following circumstances: (1) during any calendar quarter commencing after June 30, 2018, and only during such calendar quarter, if the last reported sale price of the Class A Common Stock for at least 20 trading days (whether or not consecutive) in a period of 30 consecutive trading days ending on the last trading day of the immediately preceding calendar quarter is more than 130% of the conversion price on each applicable trading day; (2) during the five business days period after any five consecutive trading days period in which, for each trading day of that period, the trading price per $1,000 principal amount of Notes for such trading day was less than 98% of the product of the last reported sale price of the Class A Common Stock and the conversion rate on each such trading day; (3) upon the Company’s notice that it is redeeming any or all of the Notes, at any time prior to the close of business on the scheduled trading day immediately preceding the redemption date; or (4) upon the occurrence of specified corporate events. On or after December 15, 2022, until the close of business on the scheduled trading day immediately preceding the maturity date, holders of the Notes may convert all or a portion of their Notes regardless of the foregoing conditions. Upon conversion, the Company will pay or deliver, as the case may be, cash, shares of Class A Common Stock, or a combination of cash and shares of Class A Common Stock, at the Company’s election. It is the Company’s current intent to settle the principal amount of the Notes with cash. During the three months ended March 31, 2018, the conditions allowing holders of the Notes to convert were not met. The Company may redeem the Notes, at its option, on or after September 20, 2020, at a redemption price equal to 100% of the principal amount thereof, plus accrued and unpaid special interest if the last reported sale price of the Class A Common Stock has been at least 130% of the conversion price then in effect for at least 20 trading days (whether or not consecutive) during any 30 consecutive trading day period ending within not more than three trading days preceding the date on which the Company provides written notice of redemption. No sinking fund is provided for the Notes. Upon the occurrence of a fundamental change (as defined in the Indenture) prior to the maturity date, holders may require the Company to repurchase all or a portion of the Notes for cash at a price equal to 100% of the principal amount of the Notes to be repurchased, plus any accrued and unpaid special interest to, but excluding, the fundamental change repurchase date. The Notes are senior unsecured obligations and will rank senior in right of payment to any of the Company’s indebtedness that is expressly subordinated in right of payment to the Notes; equal in right of payment with the Company’s existing and future liabilities that are not so subordinated; effectively junior in right of payment to any of the Company’s secured indebtedness to the extent of the value of the assets securing such indebtedness; and structurally junior to all indebtedness and other liabilities (including trade payables) of current or future subsidiaries of the Company. The foregoing description is qualified in its entirety by reference to the text of the Indenture and the Form of 0% Convertible Senior Notes due 2023, which are attached as Exhibits 4.1 and 4.2, respectively, to this Quarterly Report on Form 10-Q and are incorporated herein by reference. In accounting for the issuance of the Notes, the Company separated the Notes into liability and equity components. The carrying amount of the liability component was calculated by measuring the fair value of a similar debt instrument that does not have an associated convertible feature. The carrying amount of the equity component representing the conversion option was $101.1 million and was determined by deducting the fair value of the liability component from the par value of the Notes. The equity component is not remeasured as long as it continues to meet the conditions for equity classification. The excess of the principal amount of the liability component over its carrying amount (“debt discount”) is amortized to interest expense at an effective interest rate over the contractual terms of the Notes. In accounting for the transaction costs related to the Notes, the Company allocated the total amount incurred to the liability and equity components of the Notes based on the proportion of the proceeds allocated to the debt and equity components. Issuance costs attributable to the liability component were $8.2 million were recorded as additional debt discount and will be amortized to interest expense using the effective interest method over the contractual terms of the Notes. Issuance costs attributable to the equity component were netted with the equity component in stockholders’ equity. The net carrying amount of the liability component of the Notes was as follows (in thousands): March 31, 2018 Principal $ 460,000 Unamortized discount (99,859 ) Unamortized issuance cost (8,137 ) Net carrying amount $ 352,004 The net carrying amount of the equity component of the Notes was as follows (in thousands): March 31, 2018 Proceeds allocated to the conversion option (debt discount) $ 101,141 Issuance cost (2,318 ) Net carrying amount $ 98,823 The following table sets forth the interest expense recognized related to the Notes (in thousands): March 31, 2018 Contractual interest expense $ - Amortization of debt discount 1,282 Amortization of debt issuance costs 88 Total interest expense related to the Notes $ 1,370 In connection with the offering of the Notes, the Company entered into privately-negotiated capped call transactions with certain counterparties (the “Capped Calls”). The Capped Calls each have an initial strike price of approximately $81.45 per share, subject to certain adjustments, which corresponds to the initial conversion price of the Notes. The Capped Calls have initial cap prices of $119.035 per share, subject to certain adjustments. The Capped Calls cover, subject to anti-dilution adjustments, approximately 5.6 million shares of Class A Common Stock. The Capped Calls are generally intended to reduce or offset the potential dilution to the Class A Common Stock upon any conversion of the Notes with such reduction or offset, as the case may be, subject to a cap based on the cap price. The Capped Calls settle in components with the last component expiring on March 13, 2023. The Capped Calls are subject to either adjustment or termination upon the occurrence of specified extraordinary events affecting the Company, including a merger event; a tender offer; and a nationalization, insolvency or delisting involving the Company. In addition, the Capped Calls are subject to certain specified additional disruption events that may give rise to a termination of the Capped Calls, including changes in law; insolvency filings; and hedging disruptions. The Capped Call transactions are recorded in stockholders’ equity and are not accounted for as derivatives. The net cost of $49.9 million incurred to purchase the Capped Call transactions was recorded as a reduction to additional paid-in capital on the consolidated balance sheet. Concurrently with the issuance of the Notes, the Company’s board of directors approved the repurchase of an aggregate of 239,425, or $15.0 million of, shares of the Company’s outstanding Class A Common Stock in privately negotiated transactions at a price of $62.65 per share, which was equal to the closing price per share of the Company’s Class A Common Stock on March 1, 2018, the date of the pricing of the offering of the Notes. The share repurchase was recorded as a reduction of additional paid-in capital on the consolidated balance sheet.

Commitments and Contingencies

Commitments and Contingencies	3 Months Ended
	Mar. 31, 2018
Commitments And Contingencies Disclosure [Abstract]
Commitments and Contingencies	Note 8. 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. Sales Tax Liability The Company regularly increases its sales and marketing activities in various states within the U.S., which may create nexus in those states to collect sales taxes on sales to customers. Although the Company is diligent in collecting and remitting such taxes, there is uncertainty as to what constitutes sufficient in-state presence for a state to levy taxes, fees, and surcharges for sales made over the Internet. As of March 31, 2018 and December 31, 2017, the Company recorded a long-term sales tax liability of $2.3 million and $2.6 million, respectively, which is included in other long-term liabilities, 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 condensed 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. The Company recorded a current sales tax liability for non-contingent amounts expected to be remitted in the next twelve months of $9.8 million and $9.0 million as of March 31, 2018 and December 31, 2017, respectively, which is included in accrued liabilities in the condensed consolidated balance sheet. Legal Matters From time to time, the Company may be involved in a variety of claims, lawsuits, investigations, and proceedings relating to contractual disputes, intellectual property rights, employment matters, regulatory compliance matters, and other litigation matters relating to various claims that arise in the normal course of business. 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. TCPA Matters On April 21, 2016, Supply Pro Sorbents, LLC (“SPS”) filed a putative class action against the Company in the United States District Court for the Northern District of California, alleging common law conversion and violations of the federal Telephone Consumer Protection Act (“TCPA”) arising from fax cover sheets used by the Company’s customers when sending facsimile transmissions over the Company’s system (“SPS Lawsuit”). SPS seeks statutory damages, costs, attorneys’ fees and an injunction in connection with its TCPA claim, and unspecified damages and punitive damages in connection with its conversion claim. On July 6, 2016, the Company filed a Petition for Expedited Declaratory Ruling before the Federal Communications Commission (“FCC”), requesting that the FCC issue a ruling clarifying certain portions of its regulations promulgated under TCPA at issue in the SPS Lawsuit (“Petition”). The Petition remains pending. On July 8, 2016, the Company filed a motion to dismiss the SPS Lawsuit in its entirety, along with a collateral motion to dismiss or stay the SPS Lawsuit pending a ruling by the FCC on the Company’s Petition. On October 7, 2016, the Court granted the Company’s motion to dismiss and gave SPS 20 days to amend its complaint. The Court concurrently dismissed the Company’s motion to dismiss or stay as moot. Plaintiff filed its amended complaint on October 27, 2016, alleging essentially the same theories and claims. On November 21, 2016, the Company filed a motion to dismiss the amended complaint, along with a renewed motion to dismiss or stay the case pending resolution of the FCC Petition. On July 17, 2017, the Court granted the Company’s motion to dismiss with prejudice and concurrently dismissed the Company’s motion to dismiss or stay as moot. SPS filed a notice of appeal to the Ninth Circuit Court of Appeals on July 28, 2017. SPS’s opening brief on appeal was filed on December 20, 2017, and the Company’s opposition brief was filed on February 20, 2018. SPS filed its reply brief on April 12, 2018. Oral argument in the appeal has not yet been scheduled. It is too early to predict the outcome of the SPS Lawsuit. Based on the information known by the Company as of the date of this filing and the rules and regulations applicable to the preparation of the Company’s condensed consolidated financial statements, it is not possible to provide an estimated amount of any such loss or range of loss that may occur. On November 17, 2017, Joann Hurley (“Hurley”), filed a second amended complaint in an ongoing putative class action lawsuit pending in the United States District Court for the Southern District of West Virginia, adding the Company as a named defendant and alleging that the Company and other defendants violated the TCPA and regulations promulgated thereunder by allegedly using an automated telephone dialing system to deliver prerecorded political messages to Hurley, an incumbent running for reelection, and others. Hurley alternatively alleges that the Company is vicariously liable for the actions of its co-defendants. Hurley seeks statutory, compensatory, consequential, incidental and punitive damages, costs, and attorneys’ fees in connection with her claims. The Company was served with the second amended complaint on January 4, 2018. On March 23, 2018, the Company filed a motion to dismiss the complaint for lack of standing and failure to sufficiently state a claim on which relief may be granted. Hurley filed her opposition brief on April 6, 2018, and the Company filed its reply brief on April 13, 2018. The motion is currently pending before the court. It is too early to predict the outcome of this lawsuit. Based on the information known by the Company as of the date of this filing and the rules and regulations applicable to the preparation of the Company’s condensed consolidated financial statements, it is not possible to provide an estimated amount of any such loss or range of loss that may occur. Patent Infringement Matter On April 25, 2017, Uniloc USA, Inc. and Uniloc Luxembourg, S.A. (together, “Uniloc”) filed in the U.S. District Court for the Eastern District of Texas two actions against the Company alleging infringement of U.S. Patent Nos. 7,804,948; 7,853,000; and 8,571,194 by RingCentral’s Glip unified communications application. The plaintiffs seek a declaration that the Company has infringed the patents, damages according to proof, injunctive relief, as well as their costs, attorney’s fees, expenses and interest. On October 9, 2017, the Company filed a motion to dismiss or transfer requesting that the case be transferred to the United States District Court for the Northern District of California. In response to the motion, plaintiffs filed a first amended complaint on October 24, 2017. The Company filed a renewed motion to dismiss or transfer on November 15, 2017. Although briefing on that motion has been completed, the motion has not yet been decided. On February 5, 2018, Uniloc moved to stay the litigation pending the resolution of certain third-party inter partes review proceedings (“IPRs”) before the United States Patent and Trademark Office. On February 9, 2018, the court stayed the litigation pending resolution of the IPRs without prejudice to or waiver of the Company’s motion to dismiss or transfer. This litigation is still in its earliest stages. Based on the information known by the Company as of the date of this filing and the rules and regulations applicable to the preparation of the Company’s condensed consolidated financial statements, it is not possible to provide an estimated amount of any such loss or range of loss that may occur. The Company intends to vigorously defend against this lawsuit.

Share-Based Compensation

Share-Based Compensation	3 Months Ended
	Mar. 31, 2018
Disclosure Of Compensation Related Costs Sharebased Payments [Abstract]
Share-Based Compensation	Note 9. Share-Based Compensation A summary of share-based compensation expense recognized in the Company’s condensed consolidated statements of operations is as follows (in thousands): Three Months Ended March 31, 2018 2017 Cost of revenues $ 1,010 $ 757 Research and development 3,094 1,859 Sales and marketing 5,041 3,525 General and administrative 4,122 2,794 Total share-based compensation expense $ 13,267 $ 8,935 A summary of share-based compensation expense by award type is as follows (in thousands): Three Months Ended March 31, 2018 2017 Options $ 1,128 $ 2,190 Employee stock purchase plan rights 735 461 Restricted stock units 11,404 6,284 Total share-based compensation expense $ 13,267 $ 8,935 Equity Incentive Plans As of March 31, 2018, a total of 14,271,990 shares remained available for grant under the 2013 Equity Incentive Plan (“2013 Plan”). A summary of option activity under all of the Company’s equity incentive plans at March 31, 2018 and changes during the period 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, 2017 5,286 $ 10.30 4.2 $ 201,480 Granted — — Exercised (387 ) 9.52 Canceled/Forfeited (6 ) 24.21 Outstanding at March 31, 2018 4,893 $ 10.35 3.9 $ 260,183 Vested and expected to vest as of March 31, 2018 4,841 $ 10.28 3.9 $ 257,637 Exercisable as of March 31, 2018 4,366 $ 9.62 3.9 $ 235,212 The weighted average grant date fair value of options granted and the total intrinsic value of options exercised were as follows (in thousands, except weighted average grant date fair value): Three Months Ended March 31, 2018 2017 Weighted average grant date fair value per share $ — $ 8.87 Total intrinsic value of options exercised $ 19,962 $ 5,448 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 rate, and dividend yield. No options were granted for the three months ended March 31, 2018. The weighted-average assumptions used in the option pricing model in the periods presented were as follows: Three Months Ended March 31, 2018 2017 Expected term for employees (in years) — 4.4 Expected term for non-employees (in years) 3.5 5.2 Risk-free interest rate 2.4 % 1.8 % Expected volatility 41.6 % 44.0 % Expected dividend yield 0 % 0 % As of March 31, 2018, there was approximately $3.0 million of unrecognized share-based compensation expense, net of estimated forfeitures, related to non-vested stock option grants, which will be recognized on a straight-line basis over the remaining weighted-average vesting period of approximately 1.2 years. Employee Stock Purchase Plan The Employee Stock Purchase Plan (“ESPP”) allows eligible employees to purchase shares of the Company’s Class A common stock at a discounted price, 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 periods are for a period of six months and generally start 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 Class A common stock at the beginning of the six month offering period and (ii) 90% of the fair value of the Company’s Class A common stock at the end of the six month offering period. As of March 31, 2018, there was a total of $0.3 million of unrecognized share-based compensation expense, net of estimated forfeitures, related to ESPP, which will be recognized on a straight-line basis over the remaining weighted-average vesting period of approximately 0.1 years. At March 31, 2018, a total of 3,500,243 shares were available for issuance under the ESPP. Restricted Stock Units The 2013 Plan provides for the issuance of restricted stock units (“RSUs”) to employees, directors, and consultants. RSUs issued under the 2013 Plan generally vest over four years. A summary of activity of RSUs under the 2013 Plan at March 31, 2018 and changes during the period then ended is presented in the following table: Number of Weighted- RSUs Average Aggregate Outstanding Grant Date Fair Intrinsic Value (in thousands) Value Per Share (in thousands) Outstanding at December 31, 2017 4,281 $ 25.51 $ 207,197 Granted 141 62.95 Released (429 ) 21.27 Canceled/Forfeited (113 ) 25.83 Outstanding at March 31, 2018 3,880 $ 27.32 $ 246,356 As of March 31, 2018, there was a total of $76.7 million of unrecognized share-based compensation expense, net of estimated forfeitures, related to restricted stock units, which will be recognized on a straight-line basis over the remaining weighted-average vesting period of approximately 2.6 years. Bonus Plan In December 2017, the Board adopted the Selective 2018 Key Employee Equity Bonus Plan (“KEEB Plan”), which became effective on January 1, 2018. The KEEB Plan allows the recipients to earn fully vested shares of the Company’s common stock upon the achievement of quarterly service and performance conditions. Although no RSUs were issued under the KEEB Plan as of March 31, 2018 as the service period has not yet been completed, the Company recognized an estimated $1.5 million of expense on a straight-line basis during the three months ended March 31, 2018, based on a total requisite service period of approximately 0.4 years. The unrecognized share-based compensation expense was approximately $0.8 million, which will be recognized over the remaining service period of 0.1 year. The shares issued under this plan will be issued from the Company’s 2013 Plan shares available for issuance.

Segment Reporting

Segment Reporting	3 Months Ended
	Mar. 31, 2018
Segment Reporting [Abstract]
Segment Reporting	Note 10. Segment Reporting 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 reportable segment. Concentrations Revenue by geographic location is based on the billing address of the customer. More than 90% Generally, over 69% of the Company’s total billings are collected through credit card payments. The Company’s accounts receivable balance of $55.4 million as of March 31, 2018 primarily consists of receivables due from larger customers and carriers who are billed on invoices at customary payment terms. As the Company moves up-market and acquires larger customers, the Company expects the accounts receivable balance to increase. At March 31, 2018 and December 31, 2017, one of the Company’s carriers accounted for 20% and 17% of the Company’s total accounts receivable, respectively. Long-lived assets by geographic location is based on the location of the legal entity that owns the asset. At March 31, 2018 and December 31, 2017, more than 90% and 85% of the Company’s consolidated long-lived assets, respectively, were located in the U.S. with no single country outside of the U. S. representing more than 10% of the Company’s consolidated long-lived assets.

Income Taxes

Income Taxes	3 Months Ended
	Mar. 31, 2018
Income Tax Disclosure [Abstract]
Income Taxes	Note 11. Income Taxes The provision for income taxes for the three The realization of tax benefits of net deferred tax assets is dependent upon future levels of taxable income, of an appropriate character, in the periods the items are expected to be deductible or taxable. Based on the available objective evidence, the Company does not believe it is more likely than not that the net deferred tax assets will be realizable. Accordingly, the Company has provided a full valuation allowance against the entire domestic and the majority of the foreign net deferred tax assets as of March 31, 2018 and December 31, 2017. The Company intends to maintain the full valuation allowance on the U.S. net deferred tax assets until sufficient positive evidence exists to support a reversal of, or decrease in, the valuation allowance. During the three months ended March 31, 2018, there have been no significant changes to the total amount of unrecognized tax benefits.

Basic and Diluted Net Loss Per

Basic and Diluted Net Loss Per Share	3 Months Ended
	Mar. 31, 2018
Earnings Per Share [Abstract]
Basic and Diluted Net Loss Per Share	Note 12. 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 forfeiture 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, and ESPP, to the extent dilutive. For the three months ended March 31, 2018 and 2017, 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. The following table sets forth the computation of the Company’s basic and diluted net loss per share of common stock (in thousands, except per share data): Three Months Ended March 31, 2018 2017 As Adjusted Numerator Net loss $ (2,716 ) $ (2,237 ) Denominator Weighted-average common shares for basic and diluted net loss per share 78,341 74,682 Basic and diluted net loss per share $ (0.03 ) $ (0.03 ) The following table summarizes the potentially dilutive common shares that were excluded from diluted weighted-average common shares outstanding because including them would have had an anti-dilutive effect (in thousands): Three Months Ended March 31, 2018 2017 Shares of common stock issuable under equity incentive awards outstanding 9,328 11,581 Potential common shares excluded from diluted net loss per share 9,328 11,581 Since the Company expects to settle the principal amount of its outstanding convertible senior notes in cash and any excess in shares of the Company’s common stock, the Company uses the treasury stock method for calculating any potential dilutive effect of the conversion spread on diluted net income per share, if applicable. The conversion spread will have a dilutive impact on diluted net income per share of common stock when the average market price of the Company’s common stock for a given period exceeds the conversion price of $81.45 per share for the Notes.

Related Party Transactions

Related Party Transactions	3 Months Ended
	Mar. 31, 2018
Related Party Transactions [Abstract]
Related Party Transactions	Note 13. Related Party Transactions In the ordinary course of business, the Company made purchases from Google Inc., at which one of the Company’s directors serves as President, Americas. Total payables to Google Inc. at March 31, 2018 and December 31, 2017 were $2.3 million and $1.1 million, respectively. Total expenses incurred from Google Inc. were $5.1 million and $4.0 million in the three months ended March 31, 2018 and 2017, respectively.

Description of Business and S19

Description of Business and Summary of Significant Accounting Policies (Policies)	3 Months Ended
	Mar. 31, 2018
Organization Consolidation And Presentation Of Financial Statements [Abstract]
Basis of Presentation and Consolidation	Basis of Presentation and Consolidation The unaudited condensed consolidated financial statements and accompanying notes of the Company reflect all adjustments (all of which are normal, recurring in nature and those discussed in these notes) that are, in the opinion of management, necessary for a fair presentation of the interim periods presented. All intercompany balances and transactions have been eliminated in consolidation. The results of operations for the interim periods presented are not necessarily indicative of the results to be expected for any subsequent quarter or for the entire year ending December 31, 2018. Certain information and note disclosures normally included in annual consolidated financial statements prepared in accordance with generally accepted accounting principles in the United States of America (“U.S. GAAP”) have been condensed or omitted under the rules and regulations of the Securities and Exchange Commission (“SEC”). Effective January 1, 2018, the Company adopted the requirements of Accounting Standards Update (“ASU”) No. 2014-09, Revenue from Contracts with Customers (Topic 606) the Financial Accounting Standards Board (“FASB”), Other Assets and Deferred Costs - Contracts with Customers The unaudited condensed consolidated financial statements should be read in conjunction with the Company’s audited consolidated financial statements and related notes included in the Company’s Annual Report on Form 10-K for the year ended December 31, 2017,
Use of Estimates	Use of Estimates The preparation of condensed consolidated financial statements in conformity with U.S. GAAP requires management to make estimates and assumptions that affect the reported amounts of assets and liabilities, disclosure of contingent assets and liabilities at the date of the condensed consolidated financial statements, and the reported amounts of revenues and expenses during the reporting period. The significant estimates made by management affect revenues, the allowance for doubtful accounts, deferred sales commission costs, goodwill, share-based compensation, capitalization of internally developed software, return reserves, provision for income taxes, uncertain tax positions, loss contingencies, sales tax liabilities, and accrued liabilities. Management periodically evaluates these estimates and will make adjustments prospectively based upon the results of such periodic evaluations. Actual results could differ from these estimates.
Changes in Significant Accounting Policies	Changes in Significant Accounting Policies Except for the accounting policies for revenue recognition and deferred commissions that were updated as a result of adopting Topic 606, there have been no changes to our significant accounting policies described in the Annual Report on Form 10-K for the year ended December 31, 2017, that have had a material impact on the Company’s condensed consolidated financial statements and related notes.
Revenue Recognition	Revenue Recognition The Company derives its revenues primarily from software subscriptions, sale of products, and professional services. Revenues are recognized when control of these services is transferred to the customers, in an amount that reflects the consideration the Company expects to be entitled to in exchange for those services. The Company determines revenue recognition through the following steps: • identification of the contract or the contracts, with a customer; • identification of the performance obligations in the contract; • determination of the transaction price; • allocation of the transaction price to the performance obligations in the contract; and • recognition of revenue when, or as, the Company satisfies a performance obligation. The Company recognizes revenues as follows: Software subscriptions revenue Software subscriptions revenue is generated from the sale of subscriptions to the Company’s software applications and related services, which have contractual terms typically ranging from one month to five years, and include recurring fixed plan subscription fees and variable usage-based fees for usage in excess of plan limits. Arrangements with customers do not provide the customer with the right to take possession of the Company’s software at any time. Instead, customers are granted continuous access to the services over the contractual period. The Company transfers control evenly over the contractual period by providing stand-ready service. Accordingly, the fixed consideration related to subscription is generally recognized over time on a straight-line basis over the contract term beginning on the date the Company’s service is made available to the customer. The Company may offer its customer services for no consideration during the initial months. Such discounts are recognized ratably over the term of the contract. Fees for additional minutes of usage in excess of plan limits are deemed to be variable consideration that meet the allocation exception for variable consideration as they are specific to the month that the usage occurs. The Company’s subscription contracts typically allow the customers to terminate their services within the first 30 or 60 days and receive a refund for any amounts paid. After the termination period ends, the contract is non-cancellable and the customer is obligated to pay for the remaining term of the contract. Accordingly, the Company considers the non-cancellable term of the contract to begin after the expiration of the termination period. The Company has service-level agreements with customers warranting defined levels of uptime reliability and performance and these customers can get credits or refunds if the Company fails to meet those levels. If the services do not meet certain criteria, fees are subject to adjustment or refund representing a form of variable consideration. 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 the Company’s historical experience, current trends and the Company’s expectations regarding future experience. The Company monitors the accuracy of its sales reserve estimates by reviewing actual returns and credits and adjusts them for its future expectations to determine the adequacy of its current and future reserve needs. If actual future returns and credits differ from past experience, additional reserves may be required. Other revenue Other revenue is generated from product revenues from sales of phones and professional implementation services. Product revenue is recognized when the products have been delivered to the customer. The amount of revenue recognized for products is adjusted for expected returns, which are estimated based on historical data. The Company offers professional services that support implementation and deployment of its subscription services. Professional services do not result in significant customization of the product and are generally short-term in duration. The majority of our professional services contracts are on a fixed price basis and revenue is recognized over time as services are performed. Deferred sales commission costs The Company capitalizes sales commission expenses and associated payroll taxes paid to internal sales personnel, value added resellers and channel partners that are incremental to obtaining customer contracts. These costs are deferred and then amortized over the expected period of benefit, which is estimated to be five years. The Company has determined the period of benefit taking into consideration the expected subscription term and expected renewals of its customer contracts, the duration of its relationships with its customers, its technology and other factors. Amortization expense is included in sales and marketing expenses in the accompanying condensed consolidated statement of operations. Disaggregation of revenue The following table provides information about disaggregated revenue by primary geographical markets: Three Months Ended March 31, 2018 2017 Primary geographical markets North America 95.9 % 97.1 % Others 4.1 2.9 Total revenues 100.0 % 100.0 % The Company derived approximately 86.1% and 82.9% of subscription revenues from RingCentral Office product for the three months ended March 31, 2018 and 2017, respectively. Deferred revenue During the first quarter of 2018 the Company recognized revenue of $33.7 million that was included in the corresponding deferred revenue balance at the beginning of the period. Remaining performance obligations The typical subscription term ranges from one month to five years. Contract revenue as of March 31, 2018, that has not yet been recognized was $424 million. This excludes contracts with an original expected length of less than one year. The Company expects to recognize revenue of $269 million over the next 12 months and $155 million thereafter.
Share-Based Compensation	Share-Based Compensation Share-based compensation expense resulting from options, restricted stock units (“RSUs”), performance-based awards, and employee stock purchase plan (“ESPP”) rights granted is measured as the grant date fair value of the award and is recognized using the straight-line attribution method over the requisite service period of the award, which is generally the vesting period. The Company estimates the fair value of stock options, ESPP rights, and performance based awards using the Black-Scholes-Merton option-pricing model. The Company estimates the fair value of RSUs as the closing market value of its Class A Common Stock on the grant date. For awards with performance-based and service-based conditions, compensation cost is recognized over the requisite service period if it is probable that the performance condition will be satisfied. The expense for performance-based awards is evaluated each quarter based on the achievement of the performance conditions. The effect of a change in the estimated number of performance based awards expected to be earned is recognized in the period those estimates are revised. Compensation expense for stock options and RSUs granted to non-employees is revalued, or marked to market, as of each reporting date until the stock options and RSUs are vested. Compensation expense is recognized net of estimated forfeiture activity, which is based on historical forfeiture rates.
Recent Accounting Pronouncements Not Yet Adopted	Recent Accounting Pronouncements Not Yet Adopted In February 2016, the FASB issued ASU 2016-02, Leases (Topic 842) In January 2017, the FASB issued ASU 2017-04, Simplifying the Test for Goodwill Impairment In February 2018, the FASB issues ASU 2018-03, Technical Corrections and Improvements to Financial Statements – Overall (Sub Topic 825-10) – Recognition and Measurement of Financial Assets and Financial Liabilities Financial Instruments-Overall: Recognition and Measurement of Financial Assets and Liabilities

Description of Business and S20

Description of Business and Summary of Significant Accounting Policies (Tables)	3 Months Ended
	Mar. 31, 2018
Organization Consolidation And Presentation Of Financial Statements [Abstract]
Disaggregated of Revenue by Primary Geographical Market, Major Product Lines and Timing of Revenue Recognition	The following table provides information about disaggregated revenue by primary geographical markets: Three Months Ended March 31, 2018 2017 Primary geographical markets North America 95.9 % 97.1 % Others 4.1 2.9 Total revenues 100.0 % 100.0 %

Impact of Recent Accounting P21

Impact of Recent Accounting Pronouncements (Tables)	3 Months Ended
	Mar. 31, 2018
Adoption of Topic 606
Effect of Adoption of Topic 606 on Condensed Consolidated Balance Sheet Line Items, Condensed Consolidated Statement of Operations and Condensed Consolidated Statement of Cash Flows	Select condensed consolidated balance sheet line items, which reflect the adoption of the new ASU are as follows (in thousands): December 31, 2017 As Reported Adoption of Topic 606 As Adjusted Assets Accounts receivable, net $ 45,339 $ 1,351 $ 46,690 Deferred sales commission costs — 15,424 15,424 Deferred sales commission costs, noncurrent — 37,871 37,871 Liabilities Deferred revenue 64,415 (1,498 ) 62,917 Stockholders' equity $ 172,202 $ 56,144 $ 228,346 The following table reflects the effect of adoption of Topic 606 on the Company’s condensed consolidated statement of operations for the three months ended March 31, 2017 (in thousands): Three Months Ended March 31, 2017 As Reported Adoption of Topic 606 As Adjusted Revenues Software subscriptions $ 103,687 $ 443 $ 104,130 Other 8,104 — 8,104 Total revenues 111,791 443 112,234 Gross profit 84,485 443 84,928 Operating expenses Sales and marketing 58,894 (4,629 ) 54,265 Operating loss (7,301 ) 5,072 (2,229 ) Net loss $ (7,309 ) $ 5,072 $ (2,237 ) Basic and diluted Net loss per Common Share $ (0.10 ) $ 0.07 $ (0.03 ) Weighted-average number of shares used in computing net loss per share Basic and diluted 74,682 — 74,682 The following table reflects the effect of adoption of Topic 606 on the Company’s condensed consolidated statement of cash flows for the three months ended March 31, 2017 (in thousands): Three Months Ended March 31, 2017 As Reported Adoption of Topic 606 As Adjusted Cash flows from operating activities Net loss $ (7,309 ) $ 5,072 $ (2,237 ) Adjustments to reconcile net loss to net cash provided by operating activities: Amortization of deferred sales commission costs — 2,597 2,597 Changes in operating assets and liabilities: Accounts receivable (1,371 ) (223 ) (1,594 ) Deferred sales commission costs — (7,226 ) (7,226 ) Deferred revenue 4,209 (220 ) 3,989 Net cash provided by operating activities 8,710 — 8,710

Financial Statement Components

Financial Statement Components (Tables)	3 Months Ended
	Mar. 31, 2018
Statement Of Financial Position [Abstract]
Components of Cash and Cash Equivalents	Cash and cash equivalents consisted of the following (in thousands): March 31, December 31, 2018 2017 Cash $ 44,133 $ 70,893 Money market funds 510,830 110,299 Total cash and cash equivalents $ 554,963 $ 181,192
Components of Accounts Receivable, Net	Accounts receivable, net consisted of the following (in thousands): March 31, December 31, 2018 2017 As Adjusted Accounts receivable $ 48,227 $ 42,243 Unbilled accounts receivable 8,189 5,159 Allowance for doubtful accounts (1,037 ) (712 ) Accounts receivable, net $ 55,379 $ 46,690
Components of Prepaid Expenses and Other Current Assets	Prepaid expenses and other current assets consisted of the following (in thousands): March 31, December 31, 2018 2017 Prepaid expenses $ 17,076 $ 13,690 Inventory 229 198 Other current assets 6,813 7,624 Total prepaid expenses and other current assets $ 24,118 $ 21,512
Components of Property and Equipment, Net	Property and equipment, net consisted of the following (in thousands): March 31, December 31, 2018 2017 Computer hardware and software $ 80,626 $ 74,555 Internal-use software development costs 20,867 18,217 Furniture and fixtures 6,314 6,293 Leasehold improvements 5,249 4,311 Total property and equipment 113,056 103,376 Less: accumulated depreciation and amortization (62,925 ) (60,078 ) Property and equipment, net $ 50,131 $ 43,298
Components of Accrued Liabilities	Accrued liabilities consisted of the following (in thousands): March 31, December 31, 2018 2017 Accrued compensation and benefits $ 16,401 $ 18,578 Accrued sales, use and telecom related taxes 13,366 11,828 Accrued marketing 9,943 7,020 Other accrued expenses 24,852 17,551 Total accrued liabilities $ 64,562 $ 54,977
Summary of Carrying Values of Intangible Assets	The carrying values of intangible assets are as follows (in thousands): March 31, 2018 December 31, 2017 Estimated Lives Cost Accumulated Amortization Acquired Intangibles, Net Cost Accumulated Amortization Acquired Intangibles, Net Customer relationships 2 to 5 years $ 22,822 $ 1,756 $ 21,066 $ 840 $ 840 $ - Developed technology 5 years 3,010 1,699 1,311 3,010 1,548 1,462 Total acquired intangible assets $ 25,832 $ 3,455 $ 22,377 $ 3,850 $ 2,388 $ 1,462
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): 2018 (remaining) $ 3,749 2019 4,998 2020 4,654 2021 4,396 2022 onwards 4,580 Total estimated amortization expense $ 22,377

Fair Value of Financial Instr23

Fair Value of Financial Instruments (Tables)	3 Months Ended
	Mar. 31, 2018
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 March 31, 2018 (Level 1) (Level 2) (Level 3) Cash equivalents: Money market funds $ 510,830 $ 510,830 $ — $ — Balance at December 31, 2017 (Level 1) (Level 2) (Level 3) Cash equivalents: Money market funds $ 110,299 $ 110,299 $ — $ —

Customer Base Acquisition (Tabl

Customer Base Acquisition (Tables)	3 Months Ended
	Mar. 31, 2018
Business Combinations [Abstract]
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): Fair Value Estimated Useful Life Customer relationships $ 21,982 5 years Transition Services Agreement 2,082 1 year Net assets acquired $ 24,064

Convertible Senior Notes (Table

Convertible Senior Notes (Tables)	3 Months Ended
	Mar. 31, 2018
Debt Disclosure [Abstract]
Summary of Net Carrying Amount of Liability Component and Equity Component of Notes	The net carrying amount of the liability component of the Notes was as follows (in thousands): March 31, 2018 Principal $ 460,000 Unamortized discount (99,859 ) Unamortized issuance cost (8,137 ) Net carrying amount $ 352,004 The net carrying amount of the equity component of the Notes was as follows (in thousands): March 31, 2018 Proceeds allocated to the conversion option (debt discount) $ 101,141 Issuance cost (2,318 ) Net carrying amount $ 98,823
Schedule of Interest Expense Recognized Related to Notes	The following table sets forth the interest expense recognized related to the Notes (in thousands): March 31, 2018 Contractual interest expense $ - Amortization of debt discount 1,282 Amortization of debt issuance costs 88 Total interest expense related to the Notes $ 1,370

Share-Based Compensation (Table

Share-Based Compensation (Tables)	3 Months Ended
	Mar. 31, 2018
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 condensed consolidated statements of operations is as follows (in thousands): Three Months Ended March 31, 2018 2017 Cost of revenues $ 1,010 $ 757 Research and development 3,094 1,859 Sales and marketing 5,041 3,525 General and administrative 4,122 2,794 Total share-based compensation expense $ 13,267 $ 8,935
Summary of Share-Based Compensation Expense by Award Type	A summary of share-based compensation expense by award type is as follows (in thousands): Three Months Ended March 31, 2018 2017 Options $ 1,128 $ 2,190 Employee stock purchase plan rights 735 461 Restricted stock units 11,404 6,284 Total share-based compensation expense $ 13,267 $ 8,935
Summary of Stock Option Activity Plans	A summary of option activity under all of the Company’s equity incentive plans at March 31, 2018 and changes during the period 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, 2017 5,286 $ 10.30 4.2 $ 201,480 Granted — — Exercised (387 ) 9.52 Canceled/Forfeited (6 ) 24.21 Outstanding at March 31, 2018 4,893 $ 10.35 3.9 $ 260,183 Vested and expected to vest as of March 31, 2018 4,841 $ 10.28 3.9 $ 257,637 Exercisable as of March 31, 2018 4,366 $ 9.62 3.9 $ 235,212
Weighted Average Grant Date Fair Value of Options Granted and Total Intrinsic Value of Options Exercised	The weighted average grant date fair value of options granted and the total intrinsic value of options exercised were as follows (in thousands, except weighted average grant date fair value): Three Months Ended March 31, 2018 2017 Weighted average grant date fair value per share $ — $ 8.87 Total intrinsic value of options exercised $ 19,962 $ 5,448
Weighted Average Assumptions Used to Fair Value of Stock Options Granted	The weighted-average assumptions used in the option pricing model in the periods presented were as follows: Three Months Ended March 31, 2018 2017 Expected term for employees (in years) — 4.4 Expected term for non-employees (in years) 3.5 5.2 Risk-free interest rate 2.4 % 1.8 % Expected volatility 41.6 % 44.0 % Expected dividend yield 0 % 0 %
Summary of RSUs Activity	The 2013 Plan provides for the issuance of restricted stock units (“RSUs”) to employees, directors, and consultants. RSUs issued under the 2013 Plan generally vest over four years. A summary of activity of RSUs under the 2013 Plan at March 31, 2018 and changes during the period then ended is presented in the following table: Number of Weighted- RSUs Average Aggregate Outstanding Grant Date Fair Intrinsic Value (in thousands) Value Per Share (in thousands) Outstanding at December 31, 2017 4,281 $ 25.51 $ 207,197 Granted 141 62.95 Released (429 ) 21.27 Canceled/Forfeited (113 ) 25.83 Outstanding at March 31, 2018 3,880 $ 27.32 $ 246,356

Basic and Diluted Net Loss Pe27

Basic and Diluted Net Loss Per Share (Tables)	3 Months Ended
	Mar. 31, 2018
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 of common stock (in thousands, except per share data): Three Months Ended March 31, 2018 2017 As Adjusted Numerator Net loss $ (2,716 ) $ (2,237 ) Denominator Weighted-average common shares for basic and diluted net loss per share 78,341 74,682 Basic and diluted net loss per share $ (0.03 ) $ (0.03 )
Potential Shares of Common Stock Excluded from Diluted Weighted-Average Common Shares Outstanding	The following table summarizes the potentially dilutive common shares that were excluded from diluted weighted-average common shares outstanding because including them would have had an anti-dilutive effect (in thousands): Three Months Ended March 31, 2018 2017 Shares of common stock issuable under equity incentive awards outstanding 9,328 11,581 Potential common shares excluded from diluted net loss per share 9,328 11,581

Description of Business and S28

Description of Business and Summary of Significant Accounting Policies - Additional Information (Detail) - USD ($) $ in Millions	3 Months Ended
	Mar. 31, 2018	Mar. 31, 2017
Description Of Business And Summary Of Significant Accounting Policies [Line Items]
Deferred revenue	$ 33.7
RingCentral Office Product
Description Of Business And Summary Of Significant Accounting Policies [Line Items]
Percentage of subscriptions	86.10%	82.90%
Accounting Standards Update 2014-09
Description Of Business And Summary Of Significant Accounting Policies [Line Items]
Deffered contract costs, expected amortization period of benefit	5 years
Remaining performance obligation contract revenue not yet recognized	$ 424
Remaining performance obligation revenue recognize in next twelve months	269
Remaining performance obligation revenue recognize in greater than next twelve months	$ 155
Minimum
Description Of Business And Summary Of Significant Accounting Policies [Line Items]
Contractual arrangement subscriptions period	1 month
Subscription contracts services termination period	30 days
Minimum | Accounting Standards Update 2014-09
Description Of Business And Summary Of Significant Accounting Policies [Line Items]
Remaining performance obligation, subscription term	1 month
Maximum
Description Of Business And Summary Of Significant Accounting Policies [Line Items]
Contractual arrangement subscriptions period	5 years
Subscription contracts services termination period	60 days
Maximum | Accounting Standards Update 2014-09
Description Of Business And Summary Of Significant Accounting Policies [Line Items]
Remaining performance obligation, subscription term	5 years

Description of Business and S29

Description of Business and Summary of Significant Accounting Policies - Disaggregated of Revenue by Primary Geographical Market, Major Product Lines and Timing of Revenue Recognition (Detail)	3 Months Ended
	Mar. 31, 2018	Mar. 31, 2017
Disaggregation Of Revenue [Line Items]
Total revenues	100.00%	100.00%
North America
Disaggregation Of Revenue [Line Items]
Total revenues	95.90%	97.10%
Others
Disaggregation Of Revenue [Line Items]
Total revenues	4.10%	2.90%

Impact of Recent Accounting P30

Impact of Recent Accounting Pronouncements - Effect of Adoption of ASU on Condensed Consolidated Balance Sheet Line Items (Detail) - USD ($) $ in Thousands	Mar. 31, 2018	Dec. 31, 2017
Assets
Accounts receivable, net	$ 55,379	$ 46,690
Deferred sales commission costs	16,649	15,424
Deferred sales commission costs, noncurrent	40,140	37,871
Liabilities
Deferred revenue	68,037	62,917
Stockholders' equity	$ 275,866	228,346
Adoption of Topic 606 | As Reported
Assets
Accounts receivable, net		45,339
Liabilities
Deferred revenue		64,415
Stockholders' equity		172,202
Adoption of Topic 606 | Adoption of Topic 606
Assets
Accounts receivable, net		1,351
Deferred sales commission costs		15,424
Deferred sales commission costs, noncurrent		37,871
Liabilities
Deferred revenue		(1,498)
Stockholders' equity		$ 56,144

Impact of Recent Accounting P31

Impact of Recent Accounting Pronouncements - Effect of Adoption of Topic 606 on Condensed Consolidated Statement of Operations (Detail) - USD ($) $ / shares in Units, shares in Thousands, $ in Thousands	3 Months Ended
	Mar. 31, 2018	Mar. 31, 2017
Revenues
Software subscriptions	$ 136,960	$ 104,130
Other	13,383	8,104
Total revenues	150,343	112,234
Gross profit	114,669	84,928
Operating expenses
Sales and marketing	71,920	54,265
Operating loss	(1,351)	(2,229)
Net loss	$ (2,716)	$ (2,237)
Basic and diluted	$ (0.03)	$ (0.03)
Weighted-average number of shares used in computing net loss per share
Basic and diluted	78,341	74,682
Adoption of Topic 606 | As Reported
Revenues
Software subscriptions		$ 103,687
Other		8,104
Total revenues		111,791
Gross profit		84,485
Operating expenses
Sales and marketing		58,894
Operating loss		(7,301)
Net loss		$ (7,309)
Basic and diluted		$ (0.10)
Weighted-average number of shares used in computing net loss per share
Basic and diluted		74,682
Adoption of Topic 606 | Adoption of Topic 606
Revenues
Software subscriptions		$ 443
Total revenues		443
Gross profit		443
Operating expenses
Sales and marketing		(4,629)
Operating loss		5,072
Net loss		$ 5,072
Basic and diluted		$ 0.07

Impact of Recent Accounting P32

Impact of Recent Accounting Pronouncements - Effect of Adoption of Topic 606 on Condensed Consolidated Statement of Cash Flows (Detail) - USD ($) $ in Thousands	3 Months Ended
	Mar. 31, 2018	Mar. 31, 2017
Cash flows from operating activities
Net loss	$ (2,716)	$ (2,237)
Adjustments to reconcile net loss to net cash provided by operating activities:
Amortization of deferred sales commission costs	3,984	2,597
Changes in operating assets and liabilities:
Accounts receivable	(9,243)	(1,594)
Deferred sales commission costs		(7,226)
Deferred revenue	5,120	3,989
Net cash provided by operating activities	$ 12,185	8,710
Adoption of Topic 606 | As Reported
Cash flows from operating activities
Net loss		(7,309)
Changes in operating assets and liabilities:
Accounts receivable		(1,371)
Deferred revenue		4,209
Net cash provided by operating activities		8,710
Adoption of Topic 606 | Adoption of Topic 606
Cash flows from operating activities
Net loss		5,072
Adjustments to reconcile net loss to net cash provided by operating activities:
Amortization of deferred sales commission costs		2,597
Changes in operating assets and liabilities:
Accounts receivable		(223)
Deferred sales commission costs		(7,226)
Deferred revenue		$ (220)

Other Revenue and Cost of Rev33

Other Revenue and Cost of Revenue - Additional Information (Detail) - USD ($) $ in Millions	3 Months Ended
	Mar. 31, 2018	Mar. 31, 2017
Organization Consolidation And Presentation Of Financial Statements [Abstract]
Product revenues	$ 8	$ 6.1
Product cost of revenues	$ 7.2	$ 5.9

Financial Statement Component34

Financial Statement Components - Components of Cash and Cash Equivalents (Detail) - USD ($) $ in Thousands	Mar. 31, 2018	Dec. 31, 2017
Cash And Cash Equivalents [Abstract]
Cash	$ 44,133	$ 70,893
Money market funds	510,830	110,299
Total cash and cash equivalents	$ 554,963	$ 181,192

Financial Statement Component35

Financial Statement Components - Components of Accounts Receivable, Net (Detail) - USD ($) $ in Thousands	Mar. 31, 2018	Dec. 31, 2017
Receivables [Abstract]
Accounts receivable	$ 48,227	$ 42,243
Unbilled accounts receivable	8,189	5,159
Allowance for doubtful accounts	(1,037)	(712)
Accounts receivable, net	$ 55,379	$ 46,690

Financial Statement Component36

Financial Statement Components - Components of Prepaid Expenses and Other Current Assets (Detail) - USD ($) $ in Thousands	Mar. 31, 2018	Dec. 31, 2017
Prepaid Expense And Other Assets Current [Abstract]
Prepaid expenses	$ 17,076	$ 13,690
Inventory	229	198
Other current assets	6,813	7,624
Total prepaid expenses and other current assets	$ 24,118	$ 21,512

Financial Statement Component37

Financial Statement Components - Components of Property and Equipment, Net (Detail) - USD ($) $ in Thousands	Mar. 31, 2018	Dec. 31, 2017
Property Plant And Equipment [Line Items]
Total property and equipment	$ 113,056	$ 103,376
Less: accumulated depreciation and amortization	(62,925)	(60,078)
Property and equipment, net	50,131	43,298
Computer hardware and software
Property Plant And Equipment [Line Items]
Total property and equipment	80,626	74,555
Internal-use software development costs
Property Plant And Equipment [Line Items]
Total property and equipment	20,867	18,217
Furniture and fixtures
Property Plant And Equipment [Line Items]
Total property and equipment	6,314	6,293
Leasehold improvements
Property Plant And Equipment [Line Items]
Total property and equipment	$ 5,249	$ 4,311

Financial Statement Component38

Financial Statement Components - Additional Information (Detail) - USD ($)	3 Months Ended
	Mar. 31, 2018	Mar. 31, 2017	Dec. 31, 2017
Finite Lived Intangible Assets [Line Items]
Depreciation and amortization	$ 4,500,000	$ 3,500,000
Amortization expense of Intangible Assets	1,100,000	300,000
Deferred sales commission costs	56,800,000		$ 53,300,000
Amortization of deferred sales commission costs	3,984,000	2,597,000
Impairment loss in relation to costs capitalized	$ 0	$ 0
Customer Relationships
Finite Lived Intangible Assets [Line Items]
Weighted average amortization periods	4 years 9 months 18 days
Customer relationships, acquired during period	$ 21,982,000
Developed Techonolgy
Finite Lived Intangible Assets [Line Items]
Weighted average amortization periods	2 years 2 months 12 days

Financial Statement Component39

Financial Statement Components - Components of Accrued Liabilities (Detail) - USD ($) $ in Thousands	Mar. 31, 2018	Dec. 31, 2017
Payables And Accruals [Abstract]
Accrued compensation and benefits	$ 16,401	$ 18,578
Accrued sales, use and telecom related taxes	13,366	11,828
Accrued marketing	9,943	7,020
Other accrued expenses	24,852	17,551
Total accrued liabilities	$ 64,562	$ 54,977

Financial Statement Component40

Financial Statement Components - Summary of Carrying Values of Intangible Assets (Detail) - USD ($) $ in Thousands	3 Months Ended	12 Months Ended
	Mar. 31, 2018	Dec. 31, 2017
Finite Lived Intangible Assets [Line Items]
Cost	$ 25,832	$ 3,850
Accumulated Amortization	3,455	2,388
Acquired Intangibles, Net	$ 22,377	1,462
Customer Relationships
Finite Lived Intangible Assets [Line Items]
Estimated Lives	5 years
Cost	$ 22,822	840
Accumulated Amortization	1,756	$ 840
Acquired Intangibles, Net	$ 21,066
Customer Relationships | Minimum
Finite Lived Intangible Assets [Line Items]
Estimated Lives	2 years	2 years
Customer Relationships | Maximum
Finite Lived Intangible Assets [Line Items]
Estimated Lives	5 years	5 years
Developed Techonolgy
Finite Lived Intangible Assets [Line Items]
Estimated Lives	5 years	5 years
Cost	$ 3,010	$ 3,010
Accumulated Amortization	1,699	1,548
Acquired Intangibles, Net	$ 1,311	$ 1,462

Financial Statement Component41

Financial Statement Components - Summary of Estimated Amortization Expense for Acquired Intangible Assets (Detail) - USD ($) $ in Thousands	Mar. 31, 2018	Dec. 31, 2017
Finite Lived Intangible Assets Future Amortization Expense [Abstract]
2018 (remaining)	$ 3,749
2,019	4,998
2,020	4,654
2,021	4,396
2022 onwards	4,580
Acquired Intangibles, Net	$ 22,377	$ 1,462

Fair Value of Financial Instr42

Fair Value of Financial Instruments - Financial Assets Carried at Fair Value (Detail) - Fair Value, Measurements, Recurring - Money market funds - USD ($) $ in Thousands	Mar. 31, 2018	Dec. 31, 2017
Fair Value Assets And Liabilities Measured On Recurring And Nonrecurring Basis [Line Items]
Money market funds	$ 510,830	$ 110,299
Level 1
Fair Value Assets And Liabilities Measured On Recurring And Nonrecurring Basis [Line Items]
Money market funds	$ 510,830	$ 110,299

Fair Value of Financial Instr43

Fair Value of Financial Instruments - Additional Information (Detail) - Convertible Senior Notes Due 2023 $ in Millions	Mar. 31, 2018USD ($)
Fair Value Assets And Liabilities Measured On Recurring And Nonrecurring Basis [Line Items]
Debt instrument, interest rate	0.00%
Level 2
Fair Value Assets And Liabilities Measured On Recurring And Nonrecurring Basis [Line Items]
Fair value of convertible senior notes	$ 463.8
Debt instrument, interest rate	0.00%

Customer Base Acquisition - Add

Customer Base Acquisition - Additional Information (Detail) - USD ($) $ in Thousands	Jan. 16, 2018	Mar. 31, 2018	Dec. 31, 2017
Customer Relationships
Business Acquisition [Line Items]
Total consideration allocated between intangible assets		$ 21,982
Estimated Lives		5 years
TSA
Business Acquisition [Line Items]
Total consideration allocated between intangible assets		$ 2,100
Estimated Lives		1 year
Maximum | Customer Relationships
Business Acquisition [Line Items]
Estimated Lives		5 years	5 years
Minimum | Customer Relationships
Business Acquisition [Line Items]
Estimated Lives		2 years	2 years
RingCentral Office@Hand solution
Business Acquisition [Line Items]
Total purchase consideration		$ 24,100
Cash payments	$ 20,000	20,200
Earn-out payments		$ 3,800
Customer base transition expected completion period	1 year
Period of transition services agreement	1 year
RingCentral Office@Hand solution | Maximum
Business Acquisition [Line Items]
Total purchase consideration	$ 26,000
Earn-out payments	$ 6,000

Customer Base Acquisition - Sum

Customer Base Acquisition - Summary of Fair Value of Assets Acquired (Detail) $ in Thousands	3 Months Ended
	Mar. 31, 2018USD ($)
Business Acquisition [Line Items]
Net assets acquired, Fair Value	$ 24,064
Customer Relationships
Business Acquisition [Line Items]
Fair Value	$ 21,982
Estimated Useful Life	5 years
Transition Services Agreement
Business Acquisition [Line Items]
Fair Value	$ 2,082
Estimated Useful Life	1 year

Convertible Senior Notes - Addi

Convertible Senior Notes - Additional Information (Detail)	1 Months Ended	3 Months Ended
	Mar. 31, 2018USD ($)$ / sharesshares	Mar. 31, 2018USD ($)d$ / sharesshares	Mar. 01, 2018$ / shares
Debt Instrument [Line Items]
Aggregate principal amount	$ 460,000,000	$ 460,000,000
Proceeds from issuance debt, net of discounts and issuance costs		$ 449,457,000
Descripition of convertible notes at option of holders		Prior to the close of business on the business day immediately preceding December 15, 2022, the Notes will be convertible only under the following circumstances: (1) during any calendar quarter commencing after June 30, 2018, and only during such calendar quarter, if the last reported sale price of the Class A Common Stock for at least 20 trading days (whether or not consecutive) in a period of 30 consecutive trading days ending on the last trading day of the immediately preceding calendar quarter is more than 130% of the conversion price on each applicable trading day; (2) during the five business days period after any five consecutive trading days period in which, for each trading day of that period, the trading price per $1,000 principal amount of Notes for such trading day was less than 98% of the product of the last reported sale price of the Class A Common Stock and the conversion rate on each such trading day; (3) upon the Company’s notice that it is redeeming any or all of the Notes, at any time prior to the close of business on the scheduled trading day immediately preceding the redemption date; or (4) upon the occurrence of specified corporate events.
Net cost incurred in connection with transaction		$ 49,910,000
Repurchase of common stock value		$ 15,000,000
Class A common stock
Debt Instrument [Line Items]
Repurchase of common stock shares | shares	239,425	239,425
Repurchase of common stock value		$ 15,000,000
Shares issued, price per share | $ / shares			$ 62.65
Convertible Senior Notes Due 2023
Debt Instrument [Line Items]
Debt instrument, interest rate	0.00%	0.00%
Proceeds from issuance debt, net of discounts and issuance costs	$ 449,500,000
Conversion price per share | $ / shares	$ 81.45	$ 81.45
Carrying amount of equity component representing conversion option	$ 101,141,000	$ 101,141,000
Debt issuance costs attributed to liability component		$ 8,200,000
Convertible Senior Notes Due 2023 | Capped call
Debt Instrument [Line Items]
Initial strike price | $ / shares		$ 81.45
Initial cap price | $ / shares	119.035	119.035
Settlement, expiry date		Mar. 13, 2023
Net cost incurred in connection with transaction		$ 49,900,000
Convertible Senior Notes Due 2023 | Scenario Three
Debt Instrument [Line Items]
Number of trading days | d		20
Number of consecutive trading days | d		30
Percentage of last reported sale price to conversion price on each applicable trading day		130.00%
Debt redemption price percentage		100.00%
Convertible Senior Notes Due 2023 | Class A common stock
Debt Instrument [Line Items]
Principal amount of note convertible in to shares	$ 1,000
Debt conversion, converted instrument, shares issued | shares	12.2782
Stock par value | $ / shares	$ 0.0001	$ 0.0001
Conversion price per share | $ / shares	$ 81.45	$ 81.45
Convertible Senior Notes Due 2023 | Class A common stock | Capped call
Debt Instrument [Line Items]
Option Indexed to Issuer's Equity, Shares | shares		5,600,000
Convertible Senior Notes Due 2023 | Class A common stock | Scenario One
Debt Instrument [Line Items]
Number of trading days | d		20
Number of consecutive trading days | d		30
Percentage of last reported sale price to conversion price on each applicable trading day		130.00%
Convertible Senior Notes Due 2023 | Class A common stock | Scenario Two
Debt Instrument [Line Items]
Number of consecutive trading days | d		5
Percentage of last reported sale price to conversion price on each applicable trading day		98.00%
Notes measurement business period		5 days
Convertible Senior Notes Due 2023 | Private Placement
Debt Instrument [Line Items]
Aggregate principal amount	$ 400,000,000	$ 400,000,000
Convertible Senior Notes Due 2023 | Over-Allotment
Debt Instrument [Line Items]
Additional principal amount	$ 60,000,000	$ 60,000,000

Convertible Senior Notes - Summ

Convertible Senior Notes - Summary of Net Carrying Amount of Liability Component of Notes (Detail) $ in Thousands	Mar. 31, 2018USD ($)
Debt Disclosure [Abstract]
Aggregate principal amount	$ 460,000
Unamortized discount	(99,859)
Unamortized issuance cost	(8,137)
Net carrying amount	$ 352,004

Convertible Senior Notes - Su48

Convertible Senior Notes - Summary of Net Carrying Amount of Equity Component of Notes (Detail) - Convertible Senior Notes Due 2023 $ in Thousands	Mar. 31, 2018USD ($)
Debt Instrument [Line Items]
Proceeds allocated to the conversion option (debt discount)	$ 101,141
Issuance cost	(2,318)
Net carrying amount	$ 98,823

Convertible Senior Notes - Sche

Convertible Senior Notes - Schedule of Interest Expense Recognized Related to Notes (Detail) - USD ($) $ in Thousands	3 Months Ended
	Mar. 31, 2018	Mar. 31, 2017
Debt Instrument [Line Items]
Total interest expense related to the Notes	$ 1,411	$ 79
Convertible Senior Notes Due 2023
Debt Instrument [Line Items]
Amortization of debt discount	1,282
Amortization of debt issuance costs	88
Total interest expense related to the Notes	$ 1,370

Commitments and Contingencies -

Commitments and Contingencies - Additional Information (Detail) - USD ($) $ in Millions	Mar. 31, 2018	Dec. 31, 2017
Commitments And Contingencies Disclosure [Abstract]
Long-term sales tax liability	$ 2.3	$ 2.6
Current sales tax liability for non-contingent amounts	$ 9.8	$ 9

Share-Based Compensation - Summ

Share-Based Compensation - Summary of Share-Based Compensation Expense Recognized to Statements of Operations (Detail) - USD ($) $ in Thousands	3 Months Ended
	Mar. 31, 2018	Mar. 31, 2017
Employee Service Share Based Compensation Allocation Of Recognized Period Costs [Line Items]
Share-based compensation expense	$ 13,267	$ 8,935
Cost of Revenues
Employee Service Share Based Compensation Allocation Of Recognized Period Costs [Line Items]
Share-based compensation expense	1,010	757
Research and Development
Employee Service Share Based Compensation Allocation Of Recognized Period Costs [Line Items]
Share-based compensation expense	3,094	1,859
Sales and Marketing
Employee Service Share Based Compensation Allocation Of Recognized Period Costs [Line Items]
Share-based compensation expense	5,041	3,525
General and Administrative
Employee Service Share Based Compensation Allocation Of Recognized Period Costs [Line Items]
Share-based compensation expense	$ 4,122	$ 2,794

Share-Based Compensation - Su52

Share-Based Compensation - Summary of Share-Based Compensation Expense by Award Type (Detail) - USD ($) $ in Thousands	3 Months Ended
	Mar. 31, 2018	Mar. 31, 2017
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Share-based compensation expense	$ 13,267	$ 8,935
Options
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Share-based compensation expense	1,128	2,190
Restricted Stock Units
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Share-based compensation expense	11,404	6,284
Employee Stock Purchase Plan Rights
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Share-based compensation expense	$ 735	$ 461

Share-Based Compensation - Addi

Share-Based Compensation - Additional Information (Detail) $ in Millions	3 Months Ended
	Mar. 31, 2018USD ($)shares
2013 Employee stock purchase plan
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Available for future grants | shares	3,500,243
Unrecognized share-based compensation expense, remaining weighted-average vesting periods	1 month 6 days
Eligible compensation under the Employee Stock Purchase Plan	15.00%
Purchase of maximum shares by employees under Employee Stock Purchase Plan | shares	3,000
Unrecognized share-based compensation expense | $	$ 0.3
Class A common stock | 2013 Employee stock purchase plan | Beginning of the Six Month Offering Period
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Purchase price of Employee Stock Purchase Plan as a percentage of fair value	90.00%
Class A common stock | 2013 Employee stock purchase plan | End of the Six Month Offering Period
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Purchase price of Employee Stock Purchase Plan as a percentage of fair value	90.00%
Employee Stock Option
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Unrecognized share-based compensation expense | $	$ 3
Unrecognized share-based compensation expense, remaining weighted-average vesting periods	1 year 2 months 12 days
Restricted Stock Units
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Unrecognized share-based compensation expense, remaining weighted-average vesting periods	2 years 7 months 6 days
Vesting period contractual term	4 years
Unrecognized share-based compensation expense | $	$ 76.7
2013 Equity Incentive Plan
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Available for future grants | shares	14,271,990
Number of options granted | shares	0
Key Employee Equity Bonus Plan
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Estimated share-based compensation expense recognized | $	$ 1.5
Share based compensation requisite service period recognition	4 months 24 days
Key Employee Equity Bonus Plan | Restricted Stock Units
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Unrecognized share-based compensation expense, remaining weighted-average vesting periods	1 month 6 days
Unrecognized share-based compensation expense | $	$ 0.8
Number of shares issued | shares	0

Share-Based Compensation - Su54

Share-Based Compensation - Summary of Stock Option Activity Plans (Detail) - USD ($) $ / shares in Units, shares in Thousands, $ in Thousands	3 Months Ended	12 Months Ended
	Mar. 31, 2018	Dec. 31, 2017
Number of Options Outstanding
Number of Options Outstanding, Beginning Balance	5,286
Number of Options Outstanding, Exercised	(387)
Number of Options Outstanding, Canceled/Forfeited	(6)
Number of Options Outstanding, Ending Balance	4,893	5,286
Number of Options Outstanding, Vested and expected to vest	4,841
Number of Options Outstanding, Exercisable	4,366
Weighted-Average Exercise Price Per Share
Weighted-Average Exercise Price Per Share, Beginning Balance	$ 10.30
Weighted-Average Exercise Price Per Share, Exercised	9.52
Weighted-Average Exercise Price Per Share, Canceled/Forfeited	24.21
Weighted-Average Exercise Price Per Share, Ending Balance	10.35	$ 10.30
Weighted-Average Exercise Price Per Share, Vested and expected to vest	10.28
Weighted-Average Exercise Price Per Share, Exercisable	$ 9.62
Weighted-Average Contractual Term
Weighted-Average Contractual Term	3 years 10 months 24 days	4 years 2 months 12 days
Weighted-Average Contractual Term, Vested and expected to vest	3 years 10 months 24 days
Weighted-Average Contractual Term, Exercisable	3 years 10 months 24 days
Aggregate Intrinsic Value
Aggregate Intrinsic Value, Outstanding	$ 260,183	$ 201,480
Aggregate Intrinsic Value, Vested and expected to vest	257,637
Aggregate Intrinsic Value, Exercisable	$ 235,212

Share-Based Compensation - Weig

Share-Based Compensation - Weighted Average Grant Date Fair Value of Options Granted and Total Intrinsic Value of Options Exercised (Detail) - USD ($) $ / shares in Units, $ in Thousands	3 Months Ended
	Mar. 31, 2018	Mar. 31, 2017
Disclosure Of Compensation Related Costs Sharebased Payments [Abstract]
Weighted average grant date fair value per share		$ 8.87
Total intrinsic value of options exercised	$ 19,962	$ 5,448

Share-Based Compensation - We56

Share-Based Compensation - Weighted Average Assumptions Used to Fair Value of Stock Options Granted (Detail)	3 Months Ended
	Mar. 31, 2018	Mar. 31, 2017
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Risk-free interest rate	2.40%	1.80%
Expected volatility	41.60%	44.00%
Expected dividend yield	0.00%	0.00%
Options
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Expected term (in years)		4 years 4 months 24 days
Non Employee Stock Option
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Expected term (in years)	3 years 6 months	5 years 2 months 12 days

Share-Based Compensation - Su57

Share-Based Compensation - Summary of RSUs Activity (Detail) - Restricted Stock Units - USD ($) $ / shares in Units, shares in Thousands, $ in Thousands	3 Months Ended
	Mar. 31, 2018	Dec. 31, 2017
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Number of RSUs Outstanding, Beginning Balance	4,281
Number of RSUs Outstanding, Granted	141
Number of RSUs Outstanding, Released	(429)
Number of RSUs Outstanding, Canceled/Forfeited	(113)
Number of RSUs Outstanding, Ending Balance	3,880
Weighted-Average Grant Date Fair Value Per Share, Beginning Balance	$ 25.51
Weighted-Average Grant Date Fair Value Per Share, Granted	62.95
Weighted-Average Grant Date Fair Value Per Share, Released	21.27
Weighted-Average Grant Date Fair Value Per Share, Canceled/Forfeited	25.83
Weighted-Average Grant Date Fair Value Per Share, Ending Balance	$ 27.32
Aggregate Intrinsic Value, Outstanding	$ 246,356	$ 207,197

Segment Reporting - Additional

Segment Reporting - Additional Information (Detail) $ in Thousands	3 Months Ended		12 Months Ended
	Mar. 31, 2018USD ($)SegmentCountry	Mar. 31, 2017	Dec. 31, 2017USD ($)Country
Concentration Risk [Line Items]
Number of reporting segment | Segment	1
Percentage of total billings collected through credit cards	69.00%
Accounts receivable | $	$ 55,379		$ 46,690
Accounts Receivable | Customer Concentration Risk
Concentration Risk [Line Items]
Concentration risk	20.00%		17.00%
Non-US [Member] | Long-lived Assets | Geographic Concentration Risk
Concentration Risk [Line Items]
Number of foreign countries representing more than ten percent | Country	0		0
Minimum | U.S. | Sales Revenue, Segment | Geographic Concentration Risk
Concentration Risk [Line Items]
Concentration risk	90.00%	90.00%
Minimum | U.S. | Long-lived Assets | Geographic Concentration Risk
Concentration Risk [Line Items]
Concentration risk	90.00%		85.00%

Income Taxes - Additional Infor

Income Taxes - Additional Information (Detail) - USD ($)	3 Months Ended
	Mar. 31, 2018	Mar. 31, 2017
Income Tax Disclosure [Abstract]
Provision (benefit) for income taxes	$ 27,000	$ 51,000
Unrecognized tax benefits	$ 0

Basic and Diluted Net Loss Pe60

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
	Mar. 31, 2018	Mar. 31, 2017
Numerator
Net loss	$ (2,716)	$ (2,237)
Denominator
Weighted-average common shares for basic and diluted net loss per share	78,341	74,682
Basic and diluted net loss per share	$ (0.03)	$ (0.03)

Basic and Diluted Net Loss Pe61

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	3 Months Ended
	Mar. 31, 2018	Mar. 31, 2017
Antidilutive Securities Excluded From Computation Of Earnings Per Share [Line Items]
Potential common shares excluded from diluted net loss per share	9,328	11,581
Equity Incentive Awards
Antidilutive Securities Excluded From Computation Of Earnings Per Share [Line Items]
Potential common shares excluded from diluted net loss per share	9,328	11,581

Basic and Diluted Net Loss Pe62

Basic and Diluted Net Loss Per Share - Additional Information (Detail)	Mar. 31, 2018$ / shares
Convertible Senior Notes Due 2023
Earnings Per Share [Line Items]
Conversion price per share	$ 81.45

Related Party Transactions - Ad

Related Party Transactions - Additional Information (Detail) - Google Inc. - USD ($) $ in Millions	3 Months Ended
	Mar. 31, 2018	Mar. 31, 2017	Dec. 31, 2017
Related Party Transaction [Line Items]
Total payables to related party	$ 2.3		$ 1.1
Total expenses incurred from related party	$ 5.1	$ 4