Apptio 10-Q 3 Aug 18 2018 Q2 Quarterly report Financial data

Document and Entity Information

Document and Entity Information - shares	6 Months Ended
	Jun. 30, 2018	Jul. 31, 2018
Document And Entity Information [Abstract]
Document Type	10-Q
Amendment Flag	false
Document Period End Date	Jun. 30, 2018
Document Fiscal Year Focus	2,018
Document Fiscal Period Focus	Q2
Trading Symbol	APTI
Entity Registrant Name	Apptio Inc
Entity Central Index Key	1,419,625
Current Fiscal Year End Date	--12-31
Entity Filer Category	Accelerated Filer
Entity Common Stock, Shares Outstanding		44,574,796

Condensed Consolidated Balance

Condensed Consolidated Balance Sheets (Unaudited) - USD ($) $ in Thousands	Jun. 30, 2018	Dec. 31, 2017
Current assets
Cash and cash equivalents	$ 174,994	$ 55,069
Short-term investments	74,390	93,901
Accounts receivable, net of allowance for doubtful accounts of $317 and $413	59,136	68,782
Deferred costs	13,705	11,898
Prepaid expenses and other current assets	4,824	5,079
Total current assets	327,049	234,729
Long-term assets
Property and equipment, net of accumulated depreciation of $20,982 and $17,091	9,352	10,437
Long-term investments	5,493
Deferred costs, net of current portion	18,155	17,182
Acquisition-related intangible assets, net	19,008
Goodwill	31,004
Other long-term assets	989	983
Total assets	411,050	263,331
Current liabilities
Accounts payable	6,753	5,598
Accrued payroll and other expenses	16,484	16,481
Deferred revenue	118,346	116,831
Deferred rent	940	892
Capital leases	25	21
Total current liabilities	142,548	139,823
Long-term liabilities
Convertible senior notes, net	108,153
Deferred revenue, net of current portion	6,022	2,470
Deferred rent, net of current portion	2,987	3,483
Capital leases, net of current portion	110	26
Asset retirement obligation	198	199
Total liabilities	260,018	146,001
Commitments and contingencies (Note 14)
Stockholders’ equity
Class A and Class B Common stock	5	4
Additional paid-in capital	361,277	314,301
Accumulated other comprehensive income (loss)	11	(110)
Accumulated deficit	(210,261)	(196,865)
Total stockholders’ equity	151,032	117,330
Total liabilities and stockholders' equity	$ 411,050	$ 263,331

Condensed Consolidated Balance3

Condensed Consolidated Balance Sheets (Parenthetical) (Unaudited) - USD ($) $ in Thousands	Jun. 30, 2018	Dec. 31, 2017
Statement Of Financial Position [Abstract]
Allowance for doubtful accounts	$ 444	$ 413
Accumulated depreciation	$ 24,257	$ 21,924

Condensed Consolidated Statemen

Condensed Consolidated Statements of Operations (Unaudited) - USD ($) shares in Thousands, $ in Thousands	3 Months Ended		6 Months Ended
	Jun. 30, 2018	Jun. 30, 2017	Jun. 30, 2018	Jun. 30, 2017
Revenue
Revenue	$ 59,045	$ 45,225	$ 113,115	$ 89,156
Cost of revenue
Cost of revenue	19,215	14,519	36,629	29,938
Gross profit	39,830	30,706	76,486	59,218
Operating expenses
Research and development	12,177	10,263	24,074	19,921
Sales and marketing	24,024	20,992	46,702	40,609
General and administrative	7,499	6,620	17,653	13,154
Total operating expenses	43,700	37,875	88,429	73,684
Loss from operations	(3,870)	(7,169)	(11,943)	(14,466)
Other (expense) income
Interest expense	(1,912)	(10)	(2,124)	(20)
Interest income	871	275	1,249	533
Other income (expense), net	10	(1)	(28)	(13)
Foreign exchange (loss) gain	(576)	119	(462)	66
Loss before income taxes	(5,477)	(6,786)	(13,308)	(13,900)
Benefit from (provision for) income taxes	180	(126)	(88)	(151)
Net loss	$ (5,297)	$ (6,912)	$ (13,396)	$ (14,051)
Net loss per share attributable to common stockholders, basic and diluted	$ (0.12)	$ (0.18)	$ (0.31)	$ (0.36)
Weighted-average shares used to compute net loss per share attributable to common stockholders, basic and diluted	43,921	39,175	43,345	38,793
Subscription
Revenue
Revenue	$ 49,206	$ 37,247	$ 94,677	$ 73,434
Cost of revenue
Cost of revenue	9,671	7,252	18,620	15,102
Professional services
Revenue
Revenue	9,839	7,978	18,438	15,722
Cost of revenue
Cost of revenue	$ 9,544	$ 7,267	$ 18,009	$ 14,836

Condensed Consolidated Stateme5

Condensed Consolidated Statements of Comprehensive Loss (Unaudited) - USD ($) $ in Thousands	3 Months Ended		6 Months Ended
	Jun. 30, 2018	Jun. 30, 2017	Jun. 30, 2018	Jun. 30, 2017
Statement Of Income And Comprehensive Income [Abstract]
Net loss	$ (5,297)	$ (6,912)	$ (13,396)	$ (14,051)
Other comprehensive loss
Foreign currency translation adjustment	25		45
Unrealized gain (loss) on available-for-sale securities	39	(30)	76	(53)
Total comprehensive loss	$ (5,233)	$ (6,942)	$ (13,275)	$ (14,104)

Condensed Consolidated Stateme6

Condensed Consolidated Statements of Cash Flows (Unaudited) - USD ($) $ in Thousands		6 Months Ended
		Jun. 30, 2018	Jun. 30, 2017
Cash flows from operating activities
Net loss		$ (13,396)	$ (14,051)	[1]
Adjustments to reconcile net loss to net cash provided by operating activities
Depreciation and amortization		2,684	3,082	[1]
(Accretion of discounts)/amortization of premiums on investments		(237)	54	[1]
Amortization of acquisition-related intangible assets		1,492
Amortization of deferred costs		7,950	6,616	[1]
Amortization of debt discount and issuance costs		1,774	18	[1]
Loss (gain) on disposal of property and equipment		47	(4)	[1]
Stock-based compensation		10,531	7,310	[1]
Foreign exchange loss (gain)		462	(66)	[1]
Change in operating assets and liabilities, net of impact of business combination
Accounts receivable		15,508	7,330	[1]
Prepaid expenses and other assets		89	1,481	[1]
Deferred costs		(8,163)	(6,119)	[1]
Accounts payable		839	1,037	[1]
Accrued expenses		(1,328)	(1,727)	[1]
Deferred revenue		(9,674)	(2,820)	[1]
Deferred rent		(446)	(398)	[1]
Net cash provided by operating activities		8,132	1,743	[1]
Cash flows from investing activities
Business combination, net of cash acquired		(39,041)
Purchases of property and equipment		(1,396)	(2,236)	[1]
Proceeds from sales of equipment	[1]		9
Proceeds from maturities of investments		81,550	19,700	[1]
Purchases of investments		(67,218)	(28,898)	[1]
Return of (payments for) security deposits		50	(29)	[1]
Net cash used in investing activities		(26,055)	(11,454)	[1]
Cash flows from financing activities
Proceeds from borrowings on convertible notes, net of discounts		139,438
Purchase of capped calls		(17,092)
Proceeds from exercises of common stock options		13,942	5,495	[1]
Payment of issuance costs on convertible notes		(465)
Proceeds from purchases of stock under employee stock purchase plan		2,391	2,251	[1]
Payment of initial public offering costs	[1]		(243)
Principal payments on capital lease obligations		(13)	(21)	[1]
Net cash provided by financing activities		138,201	7,482	[1]
Foreign currency effect on cash, cash equivalents and restricted cash		(353)	56	[1]
Net increase (decrease) in cash, cash equivalents and restricted cash		119,925	(2,173)	[1]
Cash, cash equivalents and restricted cash
Beginning of period		55,069	42,007	[1]
End of period		174,994	39,834	[1]
Supplemental non-cash disclosures
Debt issuance costs in accounts payable and accrued expenses		4
Purchases under capital lease obligations		144
Property and equipment additions in accounts payable and accrued expenses		347	$ 742	[1]
Class A Common Stock
Supplemental non-cash disclosures
Class A Common stock issued in business combination		$ 4,617
[1]	See Note 1 for a summary of adjustments

Description of Operations and S

Description of Operations and Summary of Significant Accounting Policies	6 Months Ended
	Jun. 30, 2018
Description Of Operations And Summary Of Significant Accounting Policies [Abstract]
Description of Operations and Summary of Significant Accounting Policies	Note 1. Description of Operations and Summary of Significant Accounting Policies Operations Apptio, Inc., or the Company, was incorporated on October 2, 2007 and is headquartered in Bellevue, Washington. The Company develops and sells Technology Business Management, or TBM, solutions. The Company’s cloud-based platform and SaaS applications enable IT leaders to analyze, optimize and plan technology investments, and benchmark their financial and operational performance against peers. The Company operates primarily in North America, Europe and Australia. Basis of Presentation The accompanying unaudited condensed consolidated financial statements have been prepared in accordance with generally accepted accounting principles in the United States of America, or GAAP, and applicable rules and regulations of the Securities and Exchange Commission, or SEC, regarding interim financial reporting. Certain information and note disclosures normally included in the financial statements prepared in accordance with GAAP have been condensed or omitted pursuant to such rules and regulations. Therefore, these condensed consolidated financial statements should be read in conjunction with the consolidated financial statements and notes included in the Company’s Annual Report on Form 10-K for the fiscal year ended December 31, 2017 filed with the SEC on February 21, 2018, or Form 10-K. The condensed consolidated balance sheet as of December 31, 2017, included herein, was derived from the audited annual financial statements as of that date, but does not include all disclosures including certain notes required by GAAP on an annual reporting basis. In the opinion of management, the accompanying unaudited condensed consolidated financial statements reflect all normal recurring adjustments necessary to fairly state the financial position, results of operations, comprehensive loss and cash flows for the interim periods, but are not necessarily indicative of the results of operations to be anticipated for the full year 2018 or any future period. Reclassifications In the condensed consolidated statements of operations, certain prior year amounts have been reclassified to conform to the current year presentation. Specifically, “interest expense” and “interest income” were previously included in the line item "interest income (expense) and other, net" and is now separately stated. There was no change to total net loss as a result of the reclassification. Principles of Consolidation The condensed consolidated financial statements include the Company and its wholly-owned subsidiaries. All intercompany balances and transactions have been eliminated. Use of Estimates The preparation of condensed consolidated financial statements in conformity with GAAP requires management to make estimates and assumptions that affect the reported amounts of assets and liabilities and the disclosure of contingent assets and liabilities at the date of the consolidated financial statements and the reported amounts of revenue and expenses during the reporting period. Actual results could differ materially from those estimates. Certain Significant Risks and Uncertainties The Company continues to be subject to the risks and challenges associated with other companies at a similar stage of development, including risks associated with: dependence on key personnel; successful marketing and sale of its solutions and adaptation of such solutions to changing market dynamics and customer preferences; competition from alternative products and services, including from larger companies that have greater name recognition, longer operating histories, more and better established customer relationships and greater resources than the Company; and the ability to raise additional capital to support future growth. Since inception through June 30, 2018, the Company has incurred losses from operations, has accumulated a deficit of $210.3 million, and has been dependent on equity and debt financing, and to a lesser extent, cash flows from operations, to fund its business. Significant Accounting Policies There have been no material changes to the Company’s significant accounting policies and estimates as previously disclosed in the Company’s Form 10-K, except for the accounting policies for revenue recognition and deferred costs that were updated as a result of adopting Accounting Standard Update, or ASU, 2014-09, Revenue from Contracts with Customers (Topic 606) Recently Adopted Accounting Pronouncements Revenue The Company derives its revenue from The Company follows a five-step approach to recognizing revenue: (1) identify the contract with a customer; (2) identify the separate performance obligations in the contract; (3) determine the transaction price; (4) allocate the transaction price to the separate performance obligations in the contract; and (5) recognize revenue when (or as) the entity satisfies a performance obligation. The Company enters The Company typically invoices customers for subscription fees in annual increments upon execution of the initial contract or subsequent renewal. The Company recognizes Professional - If Fees for The Company also sells applications through third-party resellers. These arrangements typically call for the reseller to retain a portion of the subscription fee paid by the customer as compensation. Since the Company is responsible for the fulfillment of the goods and services and have the primary responsibility for the good or service meeting customer expectations, the Company is the principal in these transactions and records revenue on a gross basis based on the amount billed to the reseller. Reseller fees are capitalized and amortized through sales and marketing expense as discussed under Deferred Costs below. All subscription and support fees that are billed in advance are recorded as a contract liability, presented in the condensed consolidated balance sheets as deferred revenue. Deferred revenue represents Deferred Costs Deferred costs consist of sales commissions earned by the Company’s sales force and fees paid to third-party resellers and are considered incremental and recoverable costs of obtaining a contract with a customer. Sales commissions for subscription contracts are deferred and then amortized on a straight-line basis over a period of benefit that the Company has determined to be four years for new subscription agreements, over the term of the respective subscription for renewals of subscription agreements, and over one year for service contracts. The Company determined the period of benefit by taking into consideration our customer contracts, our technology and other factors. These costs are classified as current or noncurrent based on the timing of when the Company expects to recognize the expense. Business Combinations The Company uses its best estimates and assumptions to assign fair value to the tangible and intangible assets acquired and liabilities assumed as of the acquisition date. The estimates are inherently uncertain and subject to refinement. During the measurement period, which may be up to one year from the acquisition date, the Company may record adjustments to the fair value of these tangible and intangible assets acquired and liabilities assumed, with the corresponding offset to goodwill. Upon the conclusion of the measurement period or final determination of the fair value of assets acquired or liabilities assumed, whichever comes first, any subsequent adjustments are recorded in the period identified in the condensed consolidated statements of operations. Goodwill and Acquisition-Related Other Intangible Assets Goodwill represents the excess of the purchase price in a business combination over the fair value of the net tangible and intangible assets acquired. The Company evaluates and tests the recoverability of goodwill for impairment at least annually, or more frequently if circumstances indicate that goodwill may not be recoverable. The Company performs the impairment testing by first assessing qualitative factors to determine whether the existence of events or circumstances leads to a determination that it is more likely than not that the fair value of its reporting unit is less than its carrying amount. If, after assessing the totality of events or circumstances, the Company determines it is more likely than not that the fair value of a reporting unit is less than its carrying amount, a goodwill impairment test is performed. To calculate any potential impairment, the Company compares the fair value of a reporting unit with its carrying amount, including goodwill. Any excess of the carrying amount of the reporting unit's goodwill over its fair value is recognized as an impairment loss, and the carrying value of goodwill is written down. For purposes of goodwill impairment testing, there is one reporting unit. The Company periodically reviews the carrying amounts of acquired intangible assets for impairment whenever events or changes in circumstances indicate that the carrying amount of the asset group may not be recoverable. The Company measures the recoverability of this asset group by comparing the amount of each asset group to the future undiscounted cash flows it expects the asset group to generate. If the Company considers any of this asset group to be impaired, the impairment to be recognized equals the amount by which the carrying value of the asset group exceeds its fair value. In addition, the Company periodically evaluates the estimated remaining useful lives of long-lived assets to determine whether events or changes in circumstances a revision to the remaining period of amortization. Intangible assets are amortized over their useful lives ranging from two to ten years. Foreign Currency Translation The functional currency for most of the Company’s foreign subsidiaries is the U.S. dollar, while one uses local currency. The results of operations for the Company’s international subsidiaries whose functional currency is the U.S. dollar are remeasured from the local currency into U.S. dollars using the average exchange rates during each period. The majority of the assets and liabilities are remeasured using exchange rates at the end of each period. All equity transactions and certain assets are remeasured using historical rates. The Company translates the foreign functional currency financial statements to U.S dollars for the entity that does not have U.S. dollars as their functional currency using the exchange rates at the balance sheet date for assets and liabilities, the period average exchange rates for revenues and expenses, and the historical exchange rates for equity transactions and certain assets. The effects of foreign currency translation adjustments are recorded in accumulated other comprehensive income (loss) as a component of stockholders' equity, and related periodic movements are summarized as a line item in the condensed consolidated statements of comprehensive loss. Convertible Senior Notes The Company accounts for the issued Convertible Senior Notes, or the Notes, as separate liability and equity components. The Company determined the carrying amount of the liability component based on the fair value of a similar debt instrument excluding the embedded conversion option. The carrying amount of the equity component representing the conversion option was determined by deducting the fair value of the liability component from the par value of the Notes as a whole. This difference represents a debt discount that is amortized to interest expense over the term of the Notes using the effective interest rate method. The equity component is not remeasured as long as it continues to meet the conditions for equity classification. The Company has allocated issuance costs incurred to the liability and equity components. Issuance costs attributable to the liability component are being amortized to interest expense over the respective term of the Notes, and issuance costs attributable to the equity components were netted with the respective equity component in additional paid in capital. In connection with the issuance of the Notes, the Company entered into capped call transactions with certain counterparties affiliated with the initial purchasers and others. By entering into the capped call transactions, the Company mitigates potential dilution resulting from the issuance of the Notes, effectively increasing the conversion price of the Notes. Recently Adopted Accounting Pronouncements In May 2014, the Financial Accounting Standards Board, or FASB, issued ASU 2014-09, Revenue from Contracts with Customers (Topic 606), The Company adopted the requirements of the new standard as of January 1, 2018, utilizing the full retrospective transition method. Adoption of the new standard resulted in changes to our policies for revenue recognition and sales commissions as detailed above. The impact of adopting the new standard on 2017 revenues in the consolidated financial statements was not material. The primary impact of adopting the new standard is the requirement for the Company to capitalize certain contract costs, such as commissions, which were previously being expensed as incurred. These costs are now capitalized and amortized over a period of benefit that the Company has determined to be between one and four years for subscription agreements. Commissions on service arrangements are now capitalized and amortized over a period of benefit that the Company has determined to be one year. The Company has adjusted its condensed consolidated financial statements from amounts previously reported due to the adoption of ASU No. 2014-09. Select unaudited condensed consolidated balance sheet line items, which reflect the adoption of ASU No. 2014-09, are as follows (in thousands): December 31, 2017 As Previously Reported Adjustments As Adjusted Assets: Deferred costs $ — $ 11,898 $ 11,898 Deferred costs, net of current portion — 17,182 17,182 Liabilities and Stockholders’ Equity Accumulated deficit (225,945 ) 29,080 (196,865 ) Select unaudited condensed consolidated statement of operations line items, which reflect the adoption of ASU No. 2014-09, are as follows (in thousands): Three Months Ended June 30, 2017 As Previously Reported Adjustments As Adjusted Operating expenses: Sales and marketing $ 21,094 $ (102 ) $ 20,992 Loss from operations (7,271 ) 102 (7,169 ) Foreign exchange loss 120 (1 ) 119 Net loss $ (7,013 ) $ 101 $ (6,912 ) Net loss per share attributable to common stockholders, basic and diluted $ (.18 ) $ - $ (.18 ) Six Months Ended June 30, 2017 As Previously Reported Adjustments As Adjusted Operating expenses: Sales and marketing $ 40,120 $ 489 $ 40,609 Loss from operations (13,977 ) (489 ) (14,466 ) Foreign exchange loss 68 (2 ) 66 Net loss $ (13,560 ) $ (491 ) $ (14,051 ) Net loss per share attributable to common stockholders, basic and diluted $ (.35 ) $ (.01 ) $ (.36 ) Select unaudited condensed consolidated statement of cash flows line items, which reflect the adoption of ASU No. 2014-09, are as follows (in thousands): Six Months Ended June 30, 2017 As Previously Reported Adjustments As Adjusted Cash flows from operating activities: Net loss $ (13,560 ) (491 ) $ (14,051 ) Adjustments to reconcile net loss to net cash provided by operating activities: Amortization of deferred costs — 6,616 6,616 Foreign exchange (gain) loss (68 ) 2 (66 ) Change in operating assets and liabilities Deferred costs — (6,119 ) (6,119 ) Net cash provided by operating activities 1,735 8 1,743 Foreign currency effect on cash, cash equivalents and restricted cash 64 (8 ) 56 Net decrease in cash, cash equivalents and restricted cash (2,173 ) — (2,173 ) Cash, cash equivalents and restricted cash End of period $ 39,834 $ — $ 39,834 New Accounting Pronouncements Not Yet Adopted In June 2018, the FASB issued ASU No. 2018-07, Compensation-Stock Compensation (Topic 718): Improvements to Nonemployee Share-Based Payment Accounting In January 2017, the FASB issued ASU No. 2017-04, Intangibles—Goodwill and Other (Topic 350): Simplifying the Test for Goodwill Impairment In October 2016, the FASB issued ASU 2016-16 , Inter-Entity Transfers of Assets other than Inventory In February 2016, the FASB issued ASU 2016-02, Leases (Topic 842)

Fair Value Measurements

Fair Value Measurements	6 Months Ended
	Jun. 30, 2018
Fair Value Disclosures [Abstract]
Fair Value Measurements	Note 2. Fair Value Measurements The following tables present information about the Company’s financial assets and liabilities that have been measured at fair value as of June 30, 2018 and December 31, 2017, and indicates the fair value hierarchy of the valuation inputs utilized to determine such fair value (in thousands): June 30, 2018 Level 1 Level 2 Total Money market funds $ 10,181 $ — $ 10,181 Corporate notes and obligations — 32,557 32,557 U.S. government treasury securities 47,326 — 47,326 $ 57,507 $ 32,557 $ 90,064 December 31, 2017 Level 1 Level 2 Total Money market funds $ 24,225 $ — $ 24,225 Corporate notes and obligations — 38,020 38,020 U.S. government treasury securities 55,881 — 55,881 $ 80,106 $ 38,020 $ 118,126 At June 30, 2018 f c

Investments

Investments	6 Months Ended
	Jun. 30, 2018
Available For Sale Securities [Abstract]
Investments	Note 3. Investments Available-for-sale securities consist of fixed-income securities that are accounted for at fair value. Available-for-sale securities with an original maturity of 90 days or less are classified within cash and cash equivalents in the condensed consolidated balance sheets. Premiums and discounts are factored into the cost basis of the investment and amortized over the life through maturity. June 30, 2018 Amortized Gross Unrealized Gross Unrealized Fair Cost Gains Losses Value Amounts maturing in one year or less Corporate notes and obligations $ 27,069 $ — $ (5 ) $ 27,064 U.S. government treasury securities 47,339 2 (15 ) 47,326 Total short-term available-for-sale debt securities $ 74,408 $ 2 $ (20 ) $ 74,390 Amounts maturing in greater than one year Corporate notes and obligations $ 5,509 $ — $ (16 ) $ 5,493 U.S. government treasury securities — — — — Total long-term available-for-sale debt securities $ 5,509 $ — $ (16 ) $ 5,493 December 31, 2017 Amortized Gross Unrealized Gross Unrealized Fair Cost Gains Losses Value Amounts maturing in one year or less Corporate notes and obligations $ 38,044 $ — $ (24 ) $ 38,020 U.S. government treasury securities 55,967 — (86 ) 55,881 Total short-term available-for-sale debt securities $ 94,011 $ — $ (110 ) $ 93,901 As interest rates increase, those securities purchased at a lower yield show a mark-to-market unrealized loss. The longer the duration of these securities, the more susceptible they are to changes in market interest rates and bond yields. The unrealized losses are due primarily to changes in interest rates. The Company regularly reviews investments for other-than-temporary impairment using both qualitative and quantitative criteria. The following table presents gross unrealized losses and fair values for those investments that were in an unrealized loss position as of June 30, 2018 aggregated by investment category and the length of time that individual securities have been in a continuous loss position (in thousands): June 30, 2018 Less than 12 months 12 months or greater Fair Value Unrealized Loss Fair Value Unrealized Loss Corporate notes and obligations $ 16,647 $ (21 ) $ — $ — U.S. government treasury securities 33,924 (14 ) — — Total available-for-sale debt securities $ 50,571 $ (35 ) $ — $ — The Company does not consider any of the unrealized losses on its investments to be other-than-temporarily impaired based on its evaluation of available evidence, which includes the Company’s intent as of June 30, 2018 to hold these investments until the cost basis is recovered. Realized gains and losses on sales of available-for-sale securities were immaterial for all periods presented.

Deferred Costs

Deferred Costs	6 Months Ended
	Jun. 30, 2018
Deferred Costs Capitalized Prepaid And Other Assets Disclosure [Abstract]
Deferred Costs	Note 4. Deferred costs Deferred costs, which primarily consist of deferred sales commissions, were $31.9 million and $29.1 million as of June 30, 2018 and December 31, 2017, respectively. The Company capitalized $5.3 million and $3.4 million during the three months ended June 30, 2018 and 2017, respectively, and $8.2 million and $6.1 million during the six months ended June 30, 2018 and 2017, respectively. In addition, the Company acquired $2.7 million of deferred costs related to capitalized commissions, in connection with the business combination noted below. Amortization expense for the deferred costs was $4.0 million and $3.3 million during the three months ended June 30, 2018 and 2017, respectively, and $7.9 million and $6.6 million during the six months ended June 30, 2018 and 2017, respectively. Impairment losses related to deferred costs were immaterial for all periods presented.

Business Combinations

Business Combinations	6 Months Ended
	Jun. 30, 2018
Business Combinations [Abstract]
Business Combinations	Note 5. Business Combinations On February 2, 2018, the Company acquired all outstanding membership interests of Digital Fuel SV, LLC, or Digital Fuel, a provider of IT business management tools, to extend its leadership role of the Technology Business Management market and broaden the Company’s customer base. The Company allocated the purchase price of the acquisition to identifiable assets acquired and liabilities assumed based on their estimated fair values as of the acquisition date. The excess of the purchase price over the aggregate fair values was recorded as goodwill. The Company calculated the fair value of the assets acquired using the income and cost approaches (or a combination thereof). Fair values were determined based on Level 3 inputs including estimated future cash flows, discount rates, royalty rates, growth rates, sales projections, retention rates and terminal values, all of which require significant management judgment. During the second quarter of 2018, the Company finalized the purchase price allocation. Measurement period adjustments recorded during the period were not material. The total consideration for this acquisition was approximately (in thousands, except share data): Cash $ 39,138 Common stock (176,406 shares) 4,617 Total $ 43,755 The following table summarizes the fair values of the tangible and intangible assets acquired and liabilities assumed as of the acquisition date (in thousands): Purchase Consideration Useful life (in years) Cash $ 97 Accounts receivable 6,267 Other tangible assets 2,804 Acquired developed technology 8,100 4 Customer contracts and related relationships 11,400 10 Order backlog 500 2 Trademarks and trade name 500 3 Accounts payable, deferred revenue and other liabilities (16,917 ) Net assets acquired 12,751 Goodwill 31,004 Total $ 43,755 The excess of purchase consideration over the fair value of net tangible and identifiable intangible assets acquired was recorded as goodwill. The Company believes the goodwill resulting from this business combination represents the synergies expected from expanded market opportunities when integrating the acquired technologies with our offerings . The acquired entity's of operations have been included in the condensed consolidated financial statements of the Company from the date of acquisition. Pro forma and historical results of operations for this acquisition are not presented as the financial impact to the Company's condensed consolidated financial statements is immaterial.

Goodwill and Acquisition-Relate

Goodwill and Acquisition-Related Intangible Assets	6 Months Ended
	Jun. 30, 2018
Goodwill And Intangible Assets Disclosure [Abstract]
Acquisition-Related Intangible Assets	Note 6. Acquisition-Related Intangible Assets Intangible assets acquired through the Company’s business combination are as follows (in thousands): June 30, 2018 Gross Carrying Amount Accumulated Amortization Net Carrying Amount Acquired developed technology $ 8,100 $ (844 ) $ 7,256 Customer contracts and related relationship assets 11,400 (475 ) $ 10,925 Order backlog 500 (104 ) $ 396 Trademarks and trade name 500 (69 ) 431 Total $ 20,500 $ (1,492 ) $ 19,008 The weighted average remaining useful life of the intangible assets is seven years. The expected future amortization expense for intangible assets as of June 30, 2018 is as follows (in thousands): Years Ending December 31, 2018 $ 1,791 2019 3,582 2020 3,353 2021 3,179 2022 1,309 Thereafter 5,794 Total future amortization expense $ 19,008

Convertible Senior Debt

Convertible Senior Debt	6 Months Ended
	Jun. 30, 2018
Debt Disclosure [Abstract]
Convertible Senior Debt	Note 7. Convertible Senior Notes In March 2018, the Company issued and sold $143.8 million aggregate principal amount of 0.875% convertible senior notes, or the Notes, in a private placement exempt from the registration requirements of the Securities Act of 1933. The Notes mature on April 1, 2023, unless earlier repurchased by the Company or converted by the holder pursuant to the terms of the Notes. Interest is payable semi-annually in arrears on April 1 and October 1 of each year, commencing on October 1, 2018. The Company received net proceeds from the offering of approximately $139.4 million, net of initial purchase discounts and debt issuance costs. The Notes are governed by an Indenture between the Company and U.S. Bank, National Association, as trustee. The Notes are unsecured and rank senior in right of payment to the Company’s future indebtedness that is expressly subordinated in right of payment to the Notes; equal in right of payment to the Company’s existing and future indebtedness that is not so subordinated; effectively subordinated 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 subordinated to all existing and future indebtedness and other liabilities incurred by the Company’s subsidiaries. Upon conversion, the Company will pay or deliver, as the case may be, cash, shares of the Company’s Class A common stock or a combination of cash and shares of Class A common stock, at the Company’s election. The Notes have an initial conversion rate of 25.4544 shares of Class A common stock per $1,000 principal amount of Notes. This represents an initial effective conversion price of approximately $39.29 per share of Class A common stock and approximately 3.7 million shares issuable upon conversion. Throughout the term of the Notes, the conversion rate may be adjusted upon the occurrence of certain events. Holders of the Notes will not receive any cash payment representing accrued and unpaid interest, if any, upon conversion of a Note, except in limited circumstances. Accrued but unpaid interest will be deemed to be paid by cash, shares of the Company’s Class A common stock or a combination of cash and shares of the Company’s Class A common stock paid or delivered, as the case may be, to the holder upon conversion of a Note. Prior to the close of business on the business day immediately preceding January 1, 2023, the Notes will be convertible at the option of holders during certain periods, only upon satisfaction of certain conditions set forth below. On or after January 1, 2023, until the close of business on the scheduled trading day immediately preceding the maturity date, holders may convert all or any portion of their Notes at the conversion rate at any time regardless of whether the conditions set forth below have been met. Holders may convert all or a portion of their Notes prior to the close of business on the business day immediately preceding January 1, 2023, in multiples of $1,000 principal amount, only under the following circumstances: • during any calendar quarter commencing after the calendar quarter ending on June 30, 2018 (and only during such calendar quarter), if the last reported sale price of the Company’s Class A common stock for at least 20 trading days (whether or not consecutive) during a period of 30 consecutive trading days ending on, and including, the last trading day of the immediately preceding calendar quarter is greater than or equal to 130% of the conversion price on each applicable trading day; • during the five business day period after any five consecutive trading day period, or the Notes Measurement Period, in which the “trading price” (as the term is defined in the Indenture) per $1,000 principal amount of notes for each trading day of such Notes Measurement Period was less than 98% of the product of the last reported sale price of the Company’s Class A common stock and the conversion rate on each such trading day; • upon the occurrence of specified corporate events described in the Indenture. The Company may not redeem the Notes prior to April 5, 2021. The Company may redeem for cash all or any portion of the Notes, at the Company’s option, on or after April 5, 2021 if the last reported sale price of our 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 (including the last trading day of such period) ending not more than three trading days preceding the date on which the Company provides notice of redemption at a redemption price equal to 100% of the principal amount of the Notes to be redeemed, plus any accrued and unpaid interest to, but excluding the redemption date. No sinking fund is provided for the Notes. As of June 30, 2018, the Notes were not yet convertible. The Company estimated the implied interest rate of its Notes to be approximately 6.34%, assuming no conversion option. Assumptions used in the estimate were a five-year LIBOR swap rate plus the Company’s credit spread as the borrowing rate of a similar nonconvertible debt instrument to determine the present value of the liability component. The estimated implied interest rate was applied to the Notes, which resulted in a fair value of the liability component of $110.0 million upon issuance, calculated as the present value of implied future payments based on the $143.8 million aggregate principal amount. The excess of the principal amount of the liability component over its carrying amount, or the debt discount, is amortized to interest expense over the term of the Notes. The $33.8 million difference between the aggregate principal amount of $143.8 million and the estimated fair value of the liability component was recorded in additional paid-in capital as the Notes were not considered redeemable. In accounting for the transaction costs related to the issuance of the Notes, the Company allocated the total amount incurred to the liability and equity components based on their estimated relative fair values. Issuance costs attributable to the liability component, totaling $3.6 million, are being amortized to interest expense over the term of the Notes, and issuance costs attributable to the equity component, totaling $1.1 million, were netted with the equity component in shareholders’ equity. The Notes consist of the following (in thousands): June 30, 2018 December 31, 2017 Liability component: Principal $ 143,750 $ — Less: debt discount, net of amortization (35,597 ) — Net carrying amount $ 108,153 — Equity component (a) 32,637 — (a) The following table sets forth total interest expense recognized related to the Notes (in thousands): Six Months Ended June 30, 2018 2017 Contractual interest expense $ 350 $ — Amortization of debt discount 1,598 — Amortization of issuance costs 176 — Total interest expense $ 2,124 — As of June 30, 2018, the fair value of the Notes, which was determined based on inputs that are observable in the market or that could be derived from, or corroborated with, observable market data, quoted price of the Notes in an over-the-counter market (Level 2), and carrying value of debt instruments (carrying value excludes the equity component of the Company’s convertible notes classified in equity) were as follows (in thousands): June 30, 2018 December 31, 2017 Fair Value Carrying Value Fair Value Carrying value Convertible senior notes $ 160,820 $ 108,153 — — In connection with the issuance of the Notes, the Company entered into capped call transactions, or Capped Calls, with certain counterparties affiliated with the initial purchasers and others. By entering into the Capped Calls, the Company mitigates potential dilution from the conversion of the Notes, effectively increasing the conversion price of the Notes. Under the Capped Calls, the Company purchased capped call options that in the aggregate relate to the total number of shares of the Company’s Class A common stock underlying the Notes, with an initial strike price of approximately $39.29 per share, which corresponds to the initial conversion price of the Notes and is subject to anti-dilution adjustments substantially similar to those applicable to the conversion rate of the Notes, and have a cap price of approximately $60.44, and is subject to certain adjustments under the terms of the Capped Calls. The cost of the purchased Capped Calls of $17.1 million was recorded to shareholders’ equity and will not be re-measured. Based on the closing price of our Class A common stock of $36.20 on June 30, 2018, the if-converted value of the Notes was less than their respective principal amounts.

Stockholders' Equity

Stockholders' Equity	6 Months Ended
	Jun. 30, 2018
Stockholders Equity Note [Abstract]
Stockholders' Equity	Note 8. Stockholders’ Equity Preferred Stock As of June 30, 2018, the Company had authorized 5,000,000 shares of preferred stock, par value $0.0001, of which no shares were outstanding. Common Stock As of June 30, 2018, the Company had authorized 451,000,000 shares of Class A common stock, par value $0.0001 per share, of which 44,567,831 shares were issued and outstanding. Holders of Class A common stock are entitled to one vote per share. During the three months ended June 30, 2018, 1,928,417 shares of Class B common stock were converted into 1,928,417 shares of Class A common stock at the request of the holders thereof. Additionally, 9,195,917 shares of Class B common stock, constituting all of the shares of Class B common stock that were issued and outstanding, were automatically converted into shares of Class A common stock, as the Class B common stock ceased to represent at least 25% of the outstanding common stock. Prior to the conversion, the Company had authorized 44,000,000 shares of Class B Common stock. Upon conversion, 36,286,260 were retired, leaving 7,713,740 shares authorized, par value $0.0001 per share. There are no shares of Class B common stock outstanding as of June 30, 2018.

Warrants

Warrants	6 Months Ended
	Jun. 30, 2018
Warrants [Abstract]
Warrants	Note 9. Warrants On March 8, 2018, the remaining warrant holder exercised warrants to purchase 10,604 shares of Class B common stock. The Company issued 5,532 shares of Class B common stock, which immediately converted to Class A common stock, through a cashless exercise of the warrants. The impact of this exercise was immaterial to the condensed consolidated financial statements. There were no remaining common stock warrants outstanding as of June 30, 2018.

Equity Incentive Plans

Equity Incentive Plans	6 Months Ended
	Jun. 30, 2018
Disclosure Of Compensation Related Costs Sharebased Payments [Abstract]
Equity Incentive Plans	Note 10. Equity Incentive Plans 2016 Equity Incentive Plan The Company’s 2016 Equity Incentive Plan, or the 2016 Plan, became effective on September 21, 2016. The 2016 Plan provides for the grant of incentive stock options, or ISOs, within the meaning of Section 422 of the Internal Revenue Code, to the Company’s employees or any of the Company’s subsidiaries’ employees, and for the grant of non-statutory stock options, or NSOs, restricted stock, restricted stock units, stock appreciation rights, performance units and performance shares to employees, directors and consultants of the Company and the Company’s subsidiaries’ employees and consultants. As of June 30, 2018, the total number of shares available for issuance under the 2016 Plan was 5,629,839. These available shares will automatically increase each January 1, by the least of 5,500,000 shares of Class A common stock, 5% of the outstanding shares of all classes of the Company’s common stock as of the last day of the Company’s immediately preceding fiscal year, and such other amount as the Company’s board of directors may determine on or before the last day of the Company’s immediately preceding fiscal year. 2016 Employee Stock Purchase Plan The Company’s Employee Stock Purchase Plan, or 2016 ESPP, became effective on September 21, 2016. As of June 30, 2018, the total number of shares of Class A common stock available for issuance under the 2016 ESPP was 1,117,643. These available shares will automatically increase each January 1, by the least of 1,600,000 shares of Class A common stock, 1% of the number of shares of all classes of the Company’s common stock outstanding on the immediately preceding fiscal year, and such lesser number of shares as determined by the Company’s board of directors. The 2016 ESPP allows eligible employees to purchase shares of the Company’s Class A common stock at a discount through payroll deductions of their eligible compensation, subject to any plan limitations. The 2016 ESPP provides for separate six-month offering periods beginning November 30 and May 31 of each fiscal year. On each purchase date, eligible employees will purchase the Company’s Class A common stock at a price per share equal to 85% of the lesser of (1) the fair market value of the Company’s Class A common stock on the first trading day of the offering period, and (2) the fair market value of the Company’s common stock on the purchase date. During the three and six months ended June 30, 2018, 125,121 shares of Class A common stock were purchased under the 2016 ESPP. Stock Options Stock option activity during the six months ended June 30, 2018 was as follows (in thousands, except per share and contractual life data): Weighted- Weighted- Average Average Remaining Total Options Exercise Price Contractual Intrinsic Outstanding per Share Life (years) Value Outstanding at December 31, 2017 7,490 $ 10.76 Options granted — — Options exercised (1,747 ) 7.98 Options forfeited or canceled (224 ) 15.36 Outstanding at June 30, 2018 5,519 $ 11.46 6.33 $ 136,542 Vested and expected to vest at June 30, 2018 5,390 $ 11.38 6.29 $ 133,804 Exercisable at June 30, 2018 3,804 $ 9.90 5.63 $ 100,037 As of June 30, 2018, there was a total of $10.1 million of unrecognized compensation cost, adjusted for estimated forfeitures, related to unvested stock-based compensation arrangements associated with options granted. That cost is expected to be recognized over a weighted-average remaining expected term of 1.9 years. RSUs RSU activity under the 2016 Plan during the six months ended June 30, 2018 was as follows (in thousands, except per share data): Weighted-Average RSUs Grant Date Fair Value Outstanding per Share Non-Vested outstanding at December 31, 2017 2,030 $ 16.15 Granted 1,124 31.37 Vested (400 ) 14.84 Forfeited or canceled (187 ) 18.42 Non-Vested outstanding at June 30, 2018 2,567 $ 22.85 As of June 30, 2018, total unrecognized compensation cost, adjusted for estimated forfeitures, related to unvested RSUs was approximately $55.1 million and the weighted-average remaining vesting period was 3.3 years. Stock-based compensation expense recognized in the Company’s statement of operations was as follows (in thousands): Three Months Ended June 30, Six Months Ended June 30, 2018 2017 2018 2017 Cost of revenue Subscription $ 289 $ 240 $ 608 $ 597 Professional services 479 230 807 548 Operating expenses Research and development 1,399 1,112 2,792 2,153 Sales and marketing 1,706 1,077 3,136 2,077 General and administrative 1,706 1,026 3,188 1,935 Total stock-based compensation $ 5,579 $ 3,685 $ 10,531 $ 7,310

Deferred Revenue and Performanc

Deferred Revenue and Performance Obligations	6 Months Ended
	Jun. 30, 2018
Revenue Recognition And Deferred Revenue [Abstract]
Deferred Revenue and Performance Obligations	Note 11. Deferred Revenue and Performance Obligations For subscription and services revenue, the Company typically invoices in advance of providing services. Deferred revenue represents the unearned revenue on cash receipts or accounts receivable for the sale of subscriptions and professional services for which services have not yet been provided. In the case where amounts are not collected, but the service has been provided and the revenue has been recognized, the amounts are recorded in accounts receivable. The opening and ending balances of the Company’s deferred revenue are as follows: Six Months Ended June 30, 2018 Subscription Services Total Deferred revenue balance at December 31, 2017 $ 110,934 $ 8,367 $ 119,301 Revenue recognized during the period (94,677 ) (15,824 ) (110,501 ) Additions to deferred revenue during the period, including deferred revenue acquired 98,095 17,473 115,568 Deferred revenue balance at June 30, 2018 $ 114,352 $ 10,016 $ 124,368 During the three months ended June 30, 2018 and 2017, $44.7 million and $34.5 million of subscription revenue was recognized, respectively, that was included in the deferred revenue balances at the beginning of the respective periods. During the three months ended June 30, 2018 and 2017, $2.4 million and $1.6 million of professional services revenue was recognized, respectively, that was included in the deferred revenue balances at the beginning of the respective periods. During the six months ended June 30, 2018 and 2017, $74.0 million and $61.1 million of subscription revenue was recognized, respectively, that was included in the deferred revenue balances at the beginning of the respective periods. During the six months ended June 30, 2018 and 2017, $5.3 million and $4.4 million of professional services revenue was recognized, respectively, that was included in the deferred revenue balances at the beginning of the respective periods. Transaction Price Allocated to the Remaining Performance Obligations As of June 30, 2018, approximately $226.9 million of subscription revenue is expected to be recognized from remaining performance obligations for subscription contracts. The Company expects to recognize revenue on approximately 90% of these remaining performance obligations over the next 24 months, with the balance recognized thereafter. As of June 30, 2018, approximately $12.1 million of services revenue is expected to be recognized from remaining performance obligations for service contracts. The Company will recognize the remaining performance obligations for services revenue as services are performed.

Net Loss Per Share Attributable

Net Loss Per Share Attributable to Common Stockholders	6 Months Ended
	Jun. 30, 2018
Earnings Per Share [Abstract]
Net Loss Per Share Attributable to Common Stockholders	Note 12. Net Loss Per Share Attributable to Common Stockholders The Company calculates basic net loss per share attributable to common stockholders by dividing the net loss attributable to common stockholders by the weighted-average number of shares of common stock outstanding during the period. The diluted net loss per share attributable to common stockholders is computed by giving effect to all potential dilutive common stock equivalents outstanding for the period. For purposes of this calculation, options to purchase common stock, common stock related to unvested restricted stock units, warrants to purchase common stock, convertible senior notes to the extent dilutive, and common stock issuable pursuant to the employee stock purchase plan are considered common stock equivalents but have been excluded from the calculation of diluted net loss per share attributable to common stockholders as their effect is antidilutive. Basic and diluted net loss per share was the same for each period presented, as the inclusion of all potential common shares outstanding would have been antidilutive. The following table sets forth the computation of basic and diluted net loss per share (in thousands, except per share data): Three Months Ended June 30, Six Months Ended June 30, 2018 2017 2018 2017 *As Adjusted *As Adjusted Numerator: Net loss attributable to common stockholders $ (5,297 ) $ (6,912 ) $ (13,396 ) $ (14,051 ) Denominator: Weighted-average common shares outstanding - basic and diluted 43,921 39,175 43,345 38,793 Net loss per common share - basic and diluted $ (0.12 ) $ (0.18 ) $ (0.31 ) $ (0.36 ) *See Note 1 for a summary of adjustments The following weighted-average outstanding shares of potentially dilutive securities were excluded from the computation of diluted net loss per share attributable to common stockholders for the periods presented because the impact of including them would have been antidilutive (in thousands): Three Months Ended June 30, Six Months Ended June 30, 2018 2017 2018 2017 *As Adjusted *As Adjusted Stock options to purchase common stock 5,993 10,145 6,463 10,587 Unvested restricted stock units (RSUs) 2,389 1,286 2,228 966 Common stock issuable under 2016 ESPP 122 212 127 231 Warrants to purchase common stock — 11 4 11 Convertible senior notes 3,515 — 1,942 — 12,019 11,654 10,764 11,795 *See Note 1 for a summary of adjustments

Segments

Segments	6 Months Ended
	Jun. 30, 2018
Segment Reporting [Abstract]
Segments	Note 13. Segments The Company operates its business as one operating segment. Its chief operating decision makers, or CODMs, are its Chief Executive Officer and Chief Financial Officer. The CODMs review separate revenue information for the Company’s subscription and professional services revenue, and all other financial information, including free cash flow, presented on a consolidated basis, for purposes of making operating decisions, assessing financial performance and allocating resources. Revenue The following table sets forth the Company’s total revenue by geographic area for the three and six months ended June 30, 2018 and 2017, as determined based on the billing address of the customer (in thousands): Three Months Ended June 30, Six Months Ended June 30, 2018 2017 2018 2017 Americas $ 40,283 $ 32,630 $ 77,874 $ 64,540 EMEA 15,561 10,492 28,747 20,542 APAC 3,201 2,103 6,494 4,074 $ 59,045 $ 45,225 $ 113,115 $ 89,156 Revenue attributed to the United States was approximately 99% and 100% of Americas revenue for the three months ended June 30, 2018 and 2017, respectively, and 98% and 99% for the six months ended June 30, 2018 and 2017, respectively.

Commitments and Contingencies

Commitments and Contingencies	6 Months Ended
	Jun. 30, 2018
Commitments And Contingencies Disclosure [Abstract]
Commitments and Contingencies	Note 14. Commitments and Contingencies Leases The Company has entered into non-cancellable operating leases, primarily related to rental of office space and certain office equipment. Certain lease agreements include rent payment escalation clauses and free rent (rent holidays). The total amount of base rentals over the term of the leases is charged to expense using the straight-line method with the amount of the rental expense in excess of lease payments recorded as a deferred rent liability. There have been no material changes to operating leases compared to those discussed in Note 11 of the notes to the consolidated financial statements as disclosed in the Company’s Form 10-K. Other Commitments The Company has entered into certain other non-cancellable agreements for software and marketing services that specify all significant terms, including fixed or minimum services to be used, pricing provisions and the approximate timing of the transaction. There have been no material changes for commitments compared to those discussed in Note 11 of the notes to the consolidated financial statements as disclosed in the Company’s Form 10-K. Legal Matters From time to time, the Company has become involved in claims and other legal matters arising in the ordinary course of business. The Company makes a provision for a liability relating to legal matters when it is both probable that a liability has been incurred and the amount of the loss can be reasonably estimated. These provisions are reviewed at least quarterly and adjusted to reflect the impacts of negotiations, estimated settlements, legal rulings, advice of legal counsel and other information and events pertaining to a particular matter. Although claims are inherently unpredictable, the Company is currently not aware of any matters that may have a material adverse effect on the Company’s business, financial position, results of operations or cash flows, individually or in the aggregate.

Description of Operations and21

Description of Operations and Summary of Significant Accounting Policies (Policies)	6 Months Ended
	Jun. 30, 2018
Description Of Operations And Summary Of Significant Accounting Policies [Abstract]
Basis of Presentation	Basis of Presentation The accompanying unaudited condensed consolidated financial statements have been prepared in accordance with generally accepted accounting principles in the United States of America, or GAAP, and applicable rules and regulations of the Securities and Exchange Commission, or SEC, regarding interim financial reporting. Certain information and note disclosures normally included in the financial statements prepared in accordance with GAAP have been condensed or omitted pursuant to such rules and regulations. Therefore, these condensed consolidated financial statements should be read in conjunction with the consolidated financial statements and notes included in the Company’s Annual Report on Form 10-K for the fiscal year ended December 31, 2017 filed with the SEC on February 21, 2018, or Form 10-K. The condensed consolidated balance sheet as of December 31, 2017, included herein, was derived from the audited annual financial statements as of that date, but does not include all disclosures including certain notes required by GAAP on an annual reporting basis. In the opinion of management, the accompanying unaudited condensed consolidated financial statements reflect all normal recurring adjustments necessary to fairly state the financial position, results of operations, comprehensive loss and cash flows for the interim periods, but are not necessarily indicative of the results of operations to be anticipated for the full year 2018 or any future period.
Reclassifications	Reclassifications In the condensed consolidated statements of operations, certain prior year amounts have been reclassified to conform to the current year presentation. Specifically, “interest expense” and “interest income” were previously included in the line item "interest income (expense) and other, net" and is now separately stated. There was no change to total net loss as a result of the reclassification.
Principles of Consolidation	Principles of Consolidation The condensed consolidated financial statements include the Company and its wholly-owned subsidiaries. All intercompany balances and transactions have been eliminated.
Use of Estimates	Use of Estimates The preparation of condensed consolidated financial statements in conformity with GAAP requires management to make estimates and assumptions that affect the reported amounts of assets and liabilities and the disclosure of contingent assets and liabilities at the date of the consolidated financial statements and the reported amounts of revenue and expenses during the reporting period. Actual results could differ materially from those estimates.
Certain Significant Risks And Uncertainties	Certain Significant Risks and Uncertainties The Company continues to be subject to the risks and challenges associated with other companies at a similar stage of development, including risks associated with: dependence on key personnel; successful marketing and sale of its solutions and adaptation of such solutions to changing market dynamics and customer preferences; competition from alternative products and services, including from larger companies that have greater name recognition, longer operating histories, more and better established customer relationships and greater resources than the Company; and the ability to raise additional capital to support future growth. Since inception through June 30, 2018, the Company has incurred losses from operations, has accumulated a deficit of $210.3 million, and has been dependent on equity and debt financing, and to a lesser extent, cash flows from operations, to fund its business.
Revenue Recognition	Revenue The Company derives its revenue from The Company follows a five-step approach to recognizing revenue: (1) identify the contract with a customer; (2) identify the separate performance obligations in the contract; (3) determine the transaction price; (4) allocate the transaction price to the separate performance obligations in the contract; and (5) recognize revenue when (or as) the entity satisfies a performance obligation. The Company enters The Company typically invoices customers for subscription fees in annual increments upon execution of the initial contract or subsequent renewal. The Company recognizes Professional - If Fees for The Company also sells applications through third-party resellers. These arrangements typically call for the reseller to retain a portion of the subscription fee paid by the customer as compensation. Since the Company is responsible for the fulfillment of the goods and services and have the primary responsibility for the good or service meeting customer expectations, the Company is the principal in these transactions and records revenue on a gross basis based on the amount billed to the reseller. Reseller fees are capitalized and amortized through sales and marketing expense as discussed under Deferred Costs below. All subscription and support fees that are billed in advance are recorded as a contract liability, presented in the condensed consolidated balance sheets as deferred revenue. Deferred revenue represents
Deferred Costs	Deferred Costs Deferred costs consist of sales commissions earned by the Company’s sales force and fees paid to third-party resellers and are considered incremental and recoverable costs of obtaining a contract with a customer. Sales commissions for subscription contracts are deferred and then amortized on a straight-line basis over a period of benefit that the Company has determined to be four years for new subscription agreements, over the term of the respective subscription for renewals of subscription agreements, and over one year for service contracts. The Company determined the period of benefit by taking into consideration our customer contracts, our technology and other factors. These costs are classified as current or noncurrent based on the timing of when the Company expects to recognize the expense.
Business Combinations	Business Combinations The Company uses its best estimates and assumptions to assign fair value to the tangible and intangible assets acquired and liabilities assumed as of the acquisition date. The estimates are inherently uncertain and subject to refinement. During the measurement period, which may be up to one year from the acquisition date, the Company may record adjustments to the fair value of these tangible and intangible assets acquired and liabilities assumed, with the corresponding offset to goodwill. Upon the conclusion of the measurement period or final determination of the fair value of assets acquired or liabilities assumed, whichever comes first, any subsequent adjustments are recorded in the period identified in the condensed consolidated statements of operations.
Goodwill and Acquisition-Related Other Intangible Assets	Goodwill and Acquisition-Related Other Intangible Assets Goodwill represents the excess of the purchase price in a business combination over the fair value of the net tangible and intangible assets acquired. The Company evaluates and tests the recoverability of goodwill for impairment at least annually, or more frequently if circumstances indicate that goodwill may not be recoverable. The Company performs the impairment testing by first assessing qualitative factors to determine whether the existence of events or circumstances leads to a determination that it is more likely than not that the fair value of its reporting unit is less than its carrying amount. If, after assessing the totality of events or circumstances, the Company determines it is more likely than not that the fair value of a reporting unit is less than its carrying amount, a goodwill impairment test is performed. To calculate any potential impairment, the Company compares the fair value of a reporting unit with its carrying amount, including goodwill. Any excess of the carrying amount of the reporting unit's goodwill over its fair value is recognized as an impairment loss, and the carrying value of goodwill is written down. For purposes of goodwill impairment testing, there is one reporting unit. The Company periodically reviews the carrying amounts of acquired intangible assets for impairment whenever events or changes in circumstances indicate that the carrying amount of the asset group may not be recoverable. The Company measures the recoverability of this asset group by comparing the amount of each asset group to the future undiscounted cash flows it expects the asset group to generate. If the Company considers any of this asset group to be impaired, the impairment to be recognized equals the amount by which the carrying value of the asset group exceeds its fair value. In addition, the Company periodically evaluates the estimated remaining useful lives of long-lived assets to determine whether events or changes in circumstances a revision to the remaining period of amortization. Intangible assets are amortized over their useful lives ranging from two to ten years.
Foreign Currency Translation	Foreign Currency Translation The functional currency for most of the Company’s foreign subsidiaries is the U.S. dollar, while one uses local currency. The results of operations for the Company’s international subsidiaries whose functional currency is the U.S. dollar are remeasured from the local currency into U.S. dollars using the average exchange rates during each period. The majority of the assets and liabilities are remeasured using exchange rates at the end of each period. All equity transactions and certain assets are remeasured using historical rates. The Company translates the foreign functional currency financial statements to U.S dollars for the entity that does not have U.S. dollars as their functional currency using the exchange rates at the balance sheet date for assets and liabilities, the period average exchange rates for revenues and expenses, and the historical exchange rates for equity transactions and certain assets. The effects of foreign currency translation adjustments are recorded in accumulated other comprehensive income (loss) as a component of stockholders' equity, and related periodic movements are summarized as a line item in the condensed consolidated statements of comprehensive loss.
Convertible Senior Notes	Convertible Senior Notes The Company accounts for the issued Convertible Senior Notes, or the Notes, as separate liability and equity components. The Company determined the carrying amount of the liability component based on the fair value of a similar debt instrument excluding the embedded conversion option. The carrying amount of the equity component representing the conversion option was determined by deducting the fair value of the liability component from the par value of the Notes as a whole. This difference represents a debt discount that is amortized to interest expense over the term of the Notes using the effective interest rate method. The equity component is not remeasured as long as it continues to meet the conditions for equity classification. The Company has allocated issuance costs incurred to the liability and equity components. Issuance costs attributable to the liability component are being amortized to interest expense over the respective term of the Notes, and issuance costs attributable to the equity components were netted with the respective equity component in additional paid in capital. In connection with the issuance of the Notes, the Company entered into capped call transactions with certain counterparties affiliated with the initial purchasers and others. By entering into the capped call transactions, the Company mitigates potential dilution resulting from the issuance of the Notes, effectively increasing the conversion price of the Notes.
Recently Adopted Accounting Pronouncements	Recently Adopted Accounting Pronouncements In May 2014, the Financial Accounting Standards Board, or FASB, issued ASU 2014-09, Revenue from Contracts with Customers (Topic 606), The Company adopted the requirements of the new standard as of January 1, 2018, utilizing the full retrospective transition method. Adoption of the new standard resulted in changes to our policies for revenue recognition and sales commissions as detailed above. The impact of adopting the new standard on 2017 revenues in the consolidated financial statements was not material. The primary impact of adopting the new standard is the requirement for the Company to capitalize certain contract costs, such as commissions, which were previously being expensed as incurred. These costs are now capitalized and amortized over a period of benefit that the Company has determined to be between one and four years for subscription agreements. Commissions on service arrangements are now capitalized and amortized over a period of benefit that the Company has determined to be one year. The Company has adjusted its condensed consolidated financial statements from amounts previously reported due to the adoption of ASU No. 2014-09. Select unaudited condensed consolidated balance sheet line items, which reflect the adoption of ASU No. 2014-09, are as follows (in thousands): December 31, 2017 As Previously Reported Adjustments As Adjusted Assets: Deferred costs $ — $ 11,898 $ 11,898 Deferred costs, net of current portion — 17,182 17,182 Liabilities and Stockholders’ Equity Accumulated deficit (225,945 ) 29,080 (196,865 ) Select unaudited condensed consolidated statement of operations line items, which reflect the adoption of ASU No. 2014-09, are as follows (in thousands): Three Months Ended June 30, 2017 As Previously Reported Adjustments As Adjusted Operating expenses: Sales and marketing $ 21,094 $ (102 ) $ 20,992 Loss from operations (7,271 ) 102 (7,169 ) Foreign exchange loss 120 (1 ) 119 Net loss $ (7,013 ) $ 101 $ (6,912 ) Net loss per share attributable to common stockholders, basic and diluted $ (.18 ) $ - $ (.18 ) Six Months Ended June 30, 2017 As Previously Reported Adjustments As Adjusted Operating expenses: Sales and marketing $ 40,120 $ 489 $ 40,609 Loss from operations (13,977 ) (489 ) (14,466 ) Foreign exchange loss 68 (2 ) 66 Net loss $ (13,560 ) $ (491 ) $ (14,051 ) Net loss per share attributable to common stockholders, basic and diluted $ (.35 ) $ (.01 ) $ (.36 ) Select unaudited condensed consolidated statement of cash flows line items, which reflect the adoption of ASU No. 2014-09, are as follows (in thousands): Six Months Ended June 30, 2017 As Previously Reported Adjustments As Adjusted Cash flows from operating activities: Net loss $ (13,560 ) (491 ) $ (14,051 ) Adjustments to reconcile net loss to net cash provided by operating activities: Amortization of deferred costs — 6,616 6,616 Foreign exchange (gain) loss (68 ) 2 (66 ) Change in operating assets and liabilities Deferred costs — (6,119 ) (6,119 ) Net cash provided by operating activities 1,735 8 1,743 Foreign currency effect on cash, cash equivalents and restricted cash 64 (8 ) 56 Net decrease in cash, cash equivalents and restricted cash (2,173 ) — (2,173 ) Cash, cash equivalents and restricted cash End of period $ 39,834 $ — $ 39,834
New Accounting Pronouncements Not Yet Adopted	New Accounting Pronouncements Not Yet Adopted In June 2018, the FASB issued ASU No. 2018-07, Compensation-Stock Compensation (Topic 718): Improvements to Nonemployee Share-Based Payment Accounting In January 2017, the FASB issued ASU No. 2017-04, Intangibles—Goodwill and Other (Topic 350): Simplifying the Test for Goodwill Impairment In October 2016, the FASB issued ASU 2016-16 , Inter-Entity Transfers of Assets other than Inventory In February 2016, the FASB issued ASU 2016-02, Leases (Topic 842)

Description of Operations and22

Description of Operations and Summary of Significant Accounting Policies (Tables)	6 Months Ended
	Jun. 30, 2018
ASU 2014-09
New Accounting Pronouncements Or Change In Accounting Principle [Line Items]
Summary of Select Unaudited Condensed Consolidated Financial Statements Reflect Adoption of Accounting Standards	The Company has adjusted its condensed consolidated financial statements from amounts previously reported due to the adoption of ASU No. 2014-09. Select unaudited condensed consolidated balance sheet line items, which reflect the adoption of ASU No. 2014-09, are as follows (in thousands): December 31, 2017 As Previously Reported Adjustments As Adjusted Assets: Deferred costs $ — $ 11,898 $ 11,898 Deferred costs, net of current portion — 17,182 17,182 Liabilities and Stockholders’ Equity Accumulated deficit (225,945 ) 29,080 (196,865 ) Select unaudited condensed consolidated statement of operations line items, which reflect the adoption of ASU No. 2014-09, are as follows (in thousands): Three Months Ended June 30, 2017 As Previously Reported Adjustments As Adjusted Operating expenses: Sales and marketing $ 21,094 $ (102 ) $ 20,992 Loss from operations (7,271 ) 102 (7,169 ) Foreign exchange loss 120 (1 ) 119 Net loss $ (7,013 ) $ 101 $ (6,912 ) Net loss per share attributable to common stockholders, basic and diluted $ (.18 ) $ - $ (.18 ) Six Months Ended June 30, 2017 As Previously Reported Adjustments As Adjusted Operating expenses: Sales and marketing $ 40,120 $ 489 $ 40,609 Loss from operations (13,977 ) (489 ) (14,466 ) Foreign exchange loss 68 (2 ) 66 Net loss $ (13,560 ) $ (491 ) $ (14,051 ) Net loss per share attributable to common stockholders, basic and diluted $ (.35 ) $ (.01 ) $ (.36 ) Select unaudited condensed consolidated statement of cash flows line items, which reflect the adoption of ASU No. 2014-09, are as follows (in thousands): Six Months Ended June 30, 2017 As Previously Reported Adjustments As Adjusted Cash flows from operating activities: Net loss $ (13,560 ) (491 ) $ (14,051 ) Adjustments to reconcile net loss to net cash provided by operating activities: Amortization of deferred costs — 6,616 6,616 Foreign exchange (gain) loss (68 ) 2 (66 ) Change in operating assets and liabilities Deferred costs — (6,119 ) (6,119 ) Net cash provided by operating activities 1,735 8 1,743 Foreign currency effect on cash, cash equivalents and restricted cash 64 (8 ) 56 Net decrease in cash, cash equivalents and restricted cash (2,173 ) — (2,173 ) Cash, cash equivalents and restricted cash End of period $ 39,834 $ — $ 39,834

Fair Value Measurements (Tables

Fair Value Measurements (Tables)	6 Months Ended
	Jun. 30, 2018
Fair Value Disclosures [Abstract]
Schedule of Financial Assets and Liabilities Measured at Fair Value	The following tables present information about the Company’s financial assets and liabilities that have been measured at fair value as of June 30, 2018 and December 31, 2017, and indicates the fair value hierarchy of the valuation inputs utilized to determine such fair value (in thousands): June 30, 2018 Level 1 Level 2 Total Money market funds $ 10,181 $ — $ 10,181 Corporate notes and obligations — 32,557 32,557 U.S. government treasury securities 47,326 — 47,326 $ 57,507 $ 32,557 $ 90,064 December 31, 2017 Level 1 Level 2 Total Money market funds $ 24,225 $ — $ 24,225 Corporate notes and obligations — 38,020 38,020 U.S. government treasury securities 55,881 — 55,881 $ 80,106 $ 38,020 $ 118,126

Investments (Tables)

Investments (Tables)	6 Months Ended
	Jun. 30, 2018
Available For Sale Securities [Abstract]
Amortized Cost and Fair Value on Available-for-Sale Investments and Unrealized Gains and Losses	The amortized cost and fair value on the available-for-sale investments and unrealized gains and losses as of June 30, 2018 and December 31, 2017 were as follows (in thousands): June 30, 2018 Amortized Gross Unrealized Gross Unrealized Fair Cost Gains Losses Value Amounts maturing in one year or less Corporate notes and obligations $ 27,069 $ — $ (5 ) $ 27,064 U.S. government treasury securities 47,339 2 (15 ) 47,326 Total short-term available-for-sale debt securities $ 74,408 $ 2 $ (20 ) $ 74,390 Amounts maturing in greater than one year Corporate notes and obligations $ 5,509 $ — $ (16 ) $ 5,493 U.S. government treasury securities — — — — Total long-term available-for-sale debt securities $ 5,509 $ — $ (16 ) $ 5,493 December 31, 2017 Amortized Gross Unrealized Gross Unrealized Fair Cost Gains Losses Value Amounts maturing in one year or less Corporate notes and obligations $ 38,044 $ — $ (24 ) $ 38,020 U.S. government treasury securities 55,967 — (86 ) 55,881 Total short-term available-for-sale debt securities $ 94,011 $ — $ (110 ) $ 93,901
Gross Unrealized Losses and Fair Value for Investments in Unrealized Loss Position	The following table presents gross unrealized losses and fair values for those investments that were in an unrealized loss position as of June 30, 2018 aggregated by investment category and the length of time that individual securities have been in a continuous loss position (in thousands): June 30, 2018 Less than 12 months 12 months or greater Fair Value Unrealized Loss Fair Value Unrealized Loss Corporate notes and obligations $ 16,647 $ (21 ) $ — $ — U.S. government treasury securities 33,924 (14 ) — — Total available-for-sale debt securities $ 50,571 $ (35 ) $ — $ —

Business Combinations (Tables)

Business Combinations (Tables)	6 Months Ended
	Jun. 30, 2018
Business Combinations [Abstract]
Summary of Total Consideration for Acquisition	The total consideration for this acquisition was approximately (in thousands, except share data): Cash $ 39,138 Common stock (176,406 shares) 4,617 Total $ 43,755
Summary of Fair Values of Tangible and Intangible Assets Acquired and Liabilities Assumed	The following table summarizes the fair values of the tangible and intangible assets acquired and liabilities assumed as of the acquisition date (in thousands): Purchase Consideration Useful life (in years) Cash $ 97 Accounts receivable 6,267 Other tangible assets 2,804 Acquired developed technology 8,100 4 Customer contracts and related relationships 11,400 10 Order backlog 500 2 Trademarks and trade name 500 3 Accounts payable, deferred revenue and other liabilities (16,917 ) Net assets acquired 12,751 Goodwill 31,004 Total $ 43,755

Goodwill and Acquisition-Rela26

Goodwill and Acquisition-Related Intangible Assets (Tables)	6 Months Ended
	Jun. 30, 2018
Goodwill And Intangible Assets Disclosure [Abstract]
Intangible Assets Acquired through Business Combination	Intangible assets acquired through the Company’s business combination are as follows (in thousands): June 30, 2018 Gross Carrying Amount Accumulated Amortization Net Carrying Amount Acquired developed technology $ 8,100 $ (844 ) $ 7,256 Customer contracts and related relationship assets 11,400 (475 ) $ 10,925 Order backlog 500 (104 ) $ 396 Trademarks and trade name 500 (69 ) 431 Total $ 20,500 $ (1,492 ) $ 19,008
Expected Future Amortization Expense for Intangible Assets	The weighted average remaining useful life of the intangible assets is seven years. The expected future amortization expense for intangible assets as of June 30, 2018 is as follows (in thousands): Years Ending December 31, 2018 $ 1,791 2019 3,582 2020 3,353 2021 3,179 2022 1,309 Thereafter 5,794 Total future amortization expense $ 19,008

Convertible Senior Debt (Tables

Convertible Senior Debt (Tables)	6 Months Ended
	Jun. 30, 2018
Debt Disclosure [Abstract]
Components of Notes	The Notes consist of the following (in thousands): June 30, 2018 December 31, 2017 Liability component: Principal $ 143,750 $ — Less: debt discount, net of amortization (35,597 ) — Net carrying amount $ 108,153 — Equity component (a) 32,637 — (a)
Interest Expense Recognized Related to Notes	The following table sets forth total interest expense recognized related to the Notes (in thousands): Six Months Ended June 30, 2018 2017 Contractual interest expense $ 350 $ — Amortization of debt discount 1,598 — Amortization of issuance costs 176 — Total interest expense $ 2,124 —
Fair Value and Carrying Value of Convertible Senior Notes	As of June 30, 2018, the fair value of the Notes, which was determined based on inputs that are observable in the market or that could be derived from, or corroborated with, observable market data, quoted price of the Notes in an over-the-counter market (Level 2), and carrying value of debt instruments (carrying value excludes the equity component of the Company’s convertible notes classified in equity) were as follows (in thousands): June 30, 2018 December 31, 2017 Fair Value Carrying Value Fair Value Carrying value Convertible senior notes $ 160,820 $ 108,153 — —

Equity Incentive Plans (Tables)

Equity Incentive Plans (Tables)	6 Months Ended
	Jun. 30, 2018
Disclosure Of Compensation Related Costs Sharebased Payments [Abstract]
Summary of Stock Option Activity	Stock option activity during the six months ended June 30, 2018 was as follows (in thousands, except per share and contractual life data): Weighted- Weighted- Average Average Remaining Total Options Exercise Price Contractual Intrinsic Outstanding per Share Life (years) Value Outstanding at December 31, 2017 7,490 $ 10.76 Options granted — — Options exercised (1,747 ) 7.98 Options forfeited or canceled (224 ) 15.36 Outstanding at June 30, 2018 5,519 $ 11.46 6.33 $ 136,542 Vested and expected to vest at June 30, 2018 5,390 $ 11.38 6.29 $ 133,804 Exercisable at June 30, 2018 3,804 $ 9.90 5.63 $ 100,037
Summary of RSU Activity Under 2016 Plan	RSU activity under the 2016 Plan during the six months ended June 30, 2018 was as follows (in thousands, except per share data): Weighted-Average RSUs Grant Date Fair Value Outstanding per Share Non-Vested outstanding at December 31, 2017 2,030 $ 16.15 Granted 1,124 31.37 Vested (400 ) 14.84 Forfeited or canceled (187 ) 18.42 Non-Vested outstanding at June 30, 2018 2,567 $ 22.85
Summary of Stock Based Compensation Expenses	Stock-based compensation expense recognized in the Company’s statement of operations was as follows (in thousands): Three Months Ended June 30, Six Months Ended June 30, 2018 2017 2018 2017 Cost of revenue Subscription $ 289 $ 240 $ 608 $ 597 Professional services 479 230 807 548 Operating expenses Research and development 1,399 1,112 2,792 2,153 Sales and marketing 1,706 1,077 3,136 2,077 General and administrative 1,706 1,026 3,188 1,935 Total stock-based compensation $ 5,579 $ 3,685 $ 10,531 $ 7,310

Deferred Revenue and Performa29

Deferred Revenue and Performance Obligations (Tables)	6 Months Ended
	Jun. 30, 2018
Revenue Recognition And Deferred Revenue [Abstract]
Summary of Deferred Revenue Balances	The opening and ending balances of the Company’s deferred revenue are as follows: Six Months Ended June 30, 2018 Subscription Services Total Deferred revenue balance at December 31, 2017 $ 110,934 $ 8,367 $ 119,301 Revenue recognized during the period (94,677 ) (15,824 ) (110,501 ) Additions to deferred revenue during the period, including deferred revenue acquired 98,095 17,473 115,568 Deferred revenue balance at June 30, 2018 $ 114,352 $ 10,016 $ 124,368

Net Loss Per Share Attributab30

Net Loss Per Share Attributable to Common Stockholders (Tables)	6 Months Ended
	Jun. 30, 2018
Earnings Per Share [Abstract]
Computation of Basic and Diluted Net Loss Per Share	The following table sets forth the computation of basic and diluted net loss per share (in thousands, except per share data): Three Months Ended June 30, Six Months Ended June 30, 2018 2017 2018 2017 *As Adjusted *As Adjusted Numerator: Net loss attributable to common stockholders $ (5,297 ) $ (6,912 ) $ (13,396 ) $ (14,051 ) Denominator: Weighted-average common shares outstanding - basic and diluted 43,921 39,175 43,345 38,793 Net loss per common share - basic and diluted $ (0.12 ) $ (0.18 ) $ (0.31 ) $ (0.36 ) *See Note 1 for a summary of adjustments
Schedule of Antidilutive Securities Excluded from Computation of Diluted Net Loss Per Share	The following weighted-average outstanding shares of potentially dilutive securities were excluded from the computation of diluted net loss per share attributable to common stockholders for the periods presented because the impact of including them would have been antidilutive (in thousands): Three Months Ended June 30, Six Months Ended June 30, 2018 2017 2018 2017 *As Adjusted *As Adjusted Stock options to purchase common stock 5,993 10,145 6,463 10,587 Unvested restricted stock units (RSUs) 2,389 1,286 2,228 966 Common stock issuable under 2016 ESPP 122 212 127 231 Warrants to purchase common stock — 11 4 11 Convertible senior notes 3,515 — 1,942 — 12,019 11,654 10,764 11,795 *See Note 1 for a summary of adjustments

Segments (Tables)

Segments (Tables)	6 Months Ended
	Jun. 30, 2018
Segment Reporting [Abstract]
Summary of Revenue by Geographic Areas	The following table sets forth the Company’s total revenue by geographic area for the three and six months ended June 30, 2018 and 2017, as determined based on the billing address of the customer (in thousands): Three Months Ended June 30, Six Months Ended June 30, 2018 2017 2018 2017 Americas $ 40,283 $ 32,630 $ 77,874 $ 64,540 EMEA 15,561 10,492 28,747 20,542 APAC 3,201 2,103 6,494 4,074 $ 59,045 $ 45,225 $ 113,115 $ 89,156

Description of Operations and32

Description of Operations and Summary of Significant Accounting Policies - Additional Information (Details) - USD ($) $ in Thousands	6 Months Ended
	Jun. 30, 2018	Dec. 31, 2017
Description Of Operations And Summary Of Significant Accounting Policies [Line Items]
Accumulated deficit	$ (210,261)	$ (196,865)
Subscription contracts
Description Of Operations And Summary Of Significant Accounting Policies [Line Items]
Contracts amortization period	4 years
Service contracts
Description Of Operations And Summary Of Significant Accounting Policies [Line Items]
Contracts amortization period	1 year

Description of Operations and33

Description of Operations and Summary of Significant Accounting Policies - Summary of Select Unaudited Condensed Consolidated Balance Sheet Reflect Adoption of Accounting Standards (Details) - USD ($) $ in Thousands	Jun. 30, 2018	Dec. 31, 2017
Assets
Deferred costs	$ 13,705	$ 11,898
Deferred costs, net of current portion	18,155	17,182
Liabilities and Stockholders’ Equity
Accumulated deficit	$ (210,261)	(196,865)
ASU 2014-09 | As Previously Reported
Liabilities and Stockholders’ Equity
Accumulated deficit		(225,945)
ASU 2014-09 | Adjustments
Assets
Deferred costs		11,898
Deferred costs, net of current portion		17,182
Liabilities and Stockholders’ Equity
Accumulated deficit		$ 29,080

Description of Operations and34

Description of Operations and Summary of Significant Accounting Policies - Summary of Select Unaudited Condensed Consolidated Statement of Operations Reflect Adoption of Accounting Standards (Details) - USD ($) $ / shares in Units, $ in Thousands	3 Months Ended		6 Months Ended
	Jun. 30, 2018	Jun. 30, 2017	Jun. 30, 2018	Jun. 30, 2017
Operating expenses
Sales and marketing	$ 24,024	$ 20,992	$ 46,702	$ 40,609
Loss from operations	(3,870)	(7,169)	(11,943)	(14,466)
Foreign exchange loss	(576)	119	(462)	66
Net loss	$ (5,297)	$ (6,912)	$ (13,396)	$ (14,051)
Net loss per share attributable to common stockholders, basic and diluted	$ (0.12)	$ (0.18)	$ (0.31)	$ (0.36)
ASU 2014-09 | As Previously Reported
Operating expenses
Sales and marketing		$ 21,094		$ 40,120
Loss from operations		(7,271)		(13,977)
Foreign exchange loss		120		68
Net loss		$ (7,013)		$ (13,560)
Net loss per share attributable to common stockholders, basic and diluted		$ (0.18)		$ (0.35)
ASU 2014-09 | Adjustments
Operating expenses
Sales and marketing		$ (102)		$ 489
Loss from operations		102		(489)
Foreign exchange loss		(1)		(2)
Net loss		$ 101		$ (491)
Net loss per share attributable to common stockholders, basic and diluted				$ (0.01)

Description of Operations and35

Description of Operations and Summary of Significant Accounting Policies - Summary of Select Unaudited Condensed Consolidated Statement of Cash Flows Reflect Adoption of Accounting Standards (Details) - USD ($) $ in Thousands	3 Months Ended			6 Months Ended
	Jun. 30, 2018	Jun. 30, 2017		Jun. 30, 2018	Jun. 30, 2017
Cash flows from operating activities
Net loss	$ (5,297)	$ (6,912)		$ (13,396)	$ (14,051)
Adjustments to reconcile net loss to net cash provided by operating activities:
Amortization of deferred costs				7,950	6,616	[1]
Foreign exchange loss (gain)				462	(66)	[1]
Change in operating assets and liabilities
Deferred costs				(8,163)	(6,119)	[1]
Net cash provided by operating activities				8,132	1,743	[1]
Foreign currency effect on cash, cash equivalents and restricted cash				(353)	56	[1]
Net decrease in cash, cash equivalents and restricted cash				119,925	(2,173)	[1]
Cash, cash equivalents and restricted cash
End of period	$ 174,994	39,834	[1]	$ 174,994	39,834	[1]
ASU 2014-09 | As Previously Reported
Cash flows from operating activities
Net loss		(7,013)			(13,560)
Adjustments to reconcile net loss to net cash provided by operating activities:
Foreign exchange loss (gain)					(68)
Change in operating assets and liabilities
Net cash provided by operating activities					1,735
Foreign currency effect on cash, cash equivalents and restricted cash					64
Net decrease in cash, cash equivalents and restricted cash					(2,173)
Cash, cash equivalents and restricted cash
End of period		39,834			39,834
ASU 2014-09 | Adjustments
Cash flows from operating activities
Net loss		$ 101			(491)
Adjustments to reconcile net loss to net cash provided by operating activities:
Amortization of deferred costs					6,616
Foreign exchange loss (gain)					2
Change in operating assets and liabilities
Deferred costs					(6,119)
Net cash provided by operating activities					8
Foreign currency effect on cash, cash equivalents and restricted cash					$ (8)
[1]	See Note 1 for a summary of adjustments

Fair Value Measurements - Sched

Fair Value Measurements - Schedule of Financial Assets and Liabilities Measured at Fair Value (Details) - USD ($) $ in Thousands	Jun. 30, 2018	Dec. 31, 2017
Fair Value Assets And Liabilities Measured On Recurring And Nonrecurring Basis Valuation Techniques [Line Items]
Fair value, net asset (liability)	$ 90,064	$ 118,126
Level 1
Fair Value Assets And Liabilities Measured On Recurring And Nonrecurring Basis Valuation Techniques [Line Items]
Fair value, net asset (liability)	57,507	80,106
Level 2
Fair Value Assets And Liabilities Measured On Recurring And Nonrecurring Basis Valuation Techniques [Line Items]
Fair value, net asset (liability)	32,557	38,020
Money Market Funds
Fair Value Assets And Liabilities Measured On Recurring And Nonrecurring Basis Valuation Techniques [Line Items]
Fair value, assets	10,181	24,225
Money Market Funds | Level 1
Fair Value Assets And Liabilities Measured On Recurring And Nonrecurring Basis Valuation Techniques [Line Items]
Fair value, assets	10,181	24,225
Corporate Notes and Obligations
Fair Value Assets And Liabilities Measured On Recurring And Nonrecurring Basis Valuation Techniques [Line Items]
Fair value, assets	32,557	38,020
Corporate Notes and Obligations | Level 2
Fair Value Assets And Liabilities Measured On Recurring And Nonrecurring Basis Valuation Techniques [Line Items]
Fair value, assets	32,557	38,020
U.S. Government Treasury Securities
Fair Value Assets And Liabilities Measured On Recurring And Nonrecurring Basis Valuation Techniques [Line Items]
Fair value, assets	47,326	55,881
U.S. Government Treasury Securities | Level 1
Fair Value Assets And Liabilities Measured On Recurring And Nonrecurring Basis Valuation Techniques [Line Items]
Fair value, assets	$ 47,326	$ 55,881

Investments - Amortized Cost an

Investments - Amortized Cost and Fair Value on Available-for-Sale Investments and Unrealized Gains and Losses (Details) - USD ($) $ in Thousands	Mar. 31, 2018	Dec. 31, 2017
Schedule Of Available For Sale Securities [Line Items]
Available-for-sale debt securities, Amortized Cost	$ 5,509
Available-for-sale debt securities, Gross Unrealized Losses	(16)
Available-for-sale debt securities, Fair Value	5,493
Amounts Maturing in One Year or Less
Schedule Of Available For Sale Securities [Line Items]
Available-for-sale debt securities, Amortized Cost	74,408	$ 94,011
Available-for-sale debt securities, Gross Unrealized Gains	2
Available-for-sale debt securities, Gross Unrealized Losses	(20)	(110)
Available-for-sale debt securities, Fair Value	74,390	93,901
Amounts Maturing in One Year or Less | Corporate Notes and Obligations
Schedule Of Available For Sale Securities [Line Items]
Available-for-sale debt securities, Amortized Cost	27,069	38,044
Available-for-sale debt securities, Gross Unrealized Losses	(5)	(24)
Available-for-sale debt securities, Fair Value	27,064	38,020
Amounts Maturing in One Year or Less | U.S. Government Treasury Securities
Schedule Of Available For Sale Securities [Line Items]
Available-for-sale debt securities, Amortized Cost	47,339	55,967
Available-for-sale debt securities, Gross Unrealized Gains	2
Available-for-sale debt securities, Gross Unrealized Losses	(15)	(86)
Available-for-sale debt securities, Fair Value	47,326	$ 55,881
Amounts Maturing in Greater than One Year | Corporate Notes and Obligations
Schedule Of Available For Sale Securities [Line Items]
Available-for-sale debt securities, Amortized Cost	5,509
Available-for-sale debt securities, Gross Unrealized Losses	(16)
Available-for-sale debt securities, Fair Value	$ 5,493

Investments - Gross Unrealized

Investments - Gross Unrealized Losses and Fair Value for Investments in Unrealized Loss Position (Details) $ in Thousands	Jun. 30, 2018USD ($)
Schedule Of Available For Sale Securities [Line Items]
Less than 12 months, Fair Value	$ 50,571
Less than 12 months, Unrealized Loss	(35)
Corporate Notes and Obligations
Schedule Of Available For Sale Securities [Line Items]
Less than 12 months, Fair Value	16,647
Less than 12 months, Unrealized Loss	(21)
U.S. Government Treasury Securities
Schedule Of Available For Sale Securities [Line Items]
Less than 12 months, Fair Value	33,924
Less than 12 months, Unrealized Loss	$ (14)

Investments - Additional Inform

Investments - Additional Information (Details)	6 Months Ended
	Jun. 30, 2018USD ($)
Available For Sale Securities [Abstract]
Other-than-temporarily impairment, unrealized losses on available-for-sale investments	$ 0

Deferred Costs - Additional Inf

Deferred Costs - Additional Information (Details) - USD ($) $ in Millions	3 Months Ended		6 Months Ended
	Jun. 30, 2018	Jun. 30, 2017	Jun. 30, 2018	Jun. 30, 2017
Deferred Costs Capitalized Prepaid And Other Assets Disclosure [Abstract]
Deferred sales commissions	$ 31.9	$ 29.1	$ 31.9	$ 29.1
Deferred costs capitalized	5.3	3.4	8.2	6.1
Acquisition related costs			2.7
Amortization expense for deferred costs	$ 4	$ 3.3	$ 7.9	$ 6.6

Business Combinations - Additio

Business Combinations - Additional Information (Details) - USD ($) $ in Millions	Feb. 02, 2018	Jun. 30, 2018
Business Acquisition [Line Items]
Acquisition related costs		$ 2.7
Digital Fuel
Business Acquisition [Line Items]
Business combination, date of acquisition	Feb. 2, 2018
Acquisition related costs	$ 1.9

Business Combinations - Summary

Business Combinations - Summary of Total Consideration for Acquisition (Details) - Digital Fuel $ in Thousands	Feb. 02, 2018USD ($)
Business Acquisition [Line Items]
Cash	$ 39,138
Common stock (176,406 shares)	4,617
Total	$ 43,755

Business Combinations - Summa43

Business Combinations - Summary of Total Consideration for Acquisition (Parenthetical) (Details)	Feb. 02, 2018shares
Digital Fuel | Class A Common Stock
Business Acquisition [Line Items]
Number of shares issued for acquisition	176,406

Business Combinations - Summa44

Business Combinations - Summary of Fair Values of Tangible and Intangible Assets Acquired and Liabilities Assumed (Details) - USD ($) $ in Thousands	6 Months Ended
	Jun. 30, 2018	Feb. 02, 2018
Business Acquisition [Line Items]
Goodwill	$ 31,004
Useful life of acquired intangible assets	7 years
Digital Fuel
Business Acquisition [Line Items]
Cash		$ 97
Accounts receivable		6,267
Other tangible assets		2,804
Accounts payable, deferred revenue and other liabilities		(16,917)
Net assets acquired		12,751
Goodwill		31,004
Total		43,755
Digital Fuel | Acquired developed technology
Business Acquisition [Line Items]
Purchase consideration of finite-lived intangibles		8,100
Useful life of acquired intangible assets	4 years
Digital Fuel | Customer contracts and related relationships
Business Acquisition [Line Items]
Purchase consideration of finite-lived intangibles		11,400
Useful life of acquired intangible assets	10 years
Digital Fuel | Order backlog
Business Acquisition [Line Items]
Purchase consideration of finite-lived intangibles		500
Useful life of acquired intangible assets	2 years
Digital Fuel | Trademarks and trade name
Business Acquisition [Line Items]
Purchase consideration of finite-lived intangibles		$ 500
Useful life of acquired intangible assets	3 years

Acquisition-Related Intangible

Acquisition-Related Intangible Assets - Intangible Assets Acquired through Business Combination (Details) $ in Thousands	Jun. 30, 2018USD ($)
Finite Lived Intangible Assets [Line Items]
Gross Carrying Amount	$ 20,500
Accumulated Amortization	(1,492)
Net Carrying Amount	19,008
Acquired developed technology
Finite Lived Intangible Assets [Line Items]
Gross Carrying Amount	8,100
Accumulated Amortization	(844)
Net Carrying Amount	7,256
Customer contracts and related relationships
Finite Lived Intangible Assets [Line Items]
Gross Carrying Amount	11,400
Accumulated Amortization	(475)
Net Carrying Amount	10,925
Order backlog
Finite Lived Intangible Assets [Line Items]
Gross Carrying Amount	500
Accumulated Amortization	(104)
Net Carrying Amount	396
Trademarks and trade name
Finite Lived Intangible Assets [Line Items]
Gross Carrying Amount	500
Accumulated Amortization	(69)
Net Carrying Amount	$ 431

Acquisition-Related Intangibl46

Acquisition-Related Intangible Assets - Additional Information (Details)	6 Months Ended
	Jun. 30, 2018
Goodwill And Intangible Assets Disclosure [Abstract]
Useful life of acquired intangible assets	7 years

Acquisition-Related Intangibl47

Acquisition-Related Intangible Assets - Expected Future Amortization Expense for Intangible Assets (Details) $ in Thousands	Jun. 30, 2018USD ($)
Goodwill And Intangible Assets Disclosure [Abstract]
2,018	$ 1,791
2,019	3,582
2,020	3,353
2,021	3,179
2,022	1,309
Thereafter	5,794
Net Carrying Amount	$ 19,008

Convertible Senior Notes - Addi

Convertible Senior Notes - Additional Information (Details) $ / shares in Units, $ in Thousands	1 Months Ended	3 Months Ended	6 Months Ended
	Mar. 31, 2018USD ($)	Mar. 31, 2018USD ($)	Jun. 30, 2018USD ($)dSinkingFund$ / sharesshares
Debt Instrument [Line Items]
Net proceeds from offering	$ 139,400		$ 139,438
Notes initial conversion rate of common stock | shares			25.4544
Conversion rate of common stock per principal amount of Notes | $ / shares			$ 1,000
Debt instrument conversion price per share | $ / shares			$ 39.29
Debt instrument shares issuable upon conversion | shares			3,700,000
Convertible notes, conversion start date			Jan. 1, 2023
Number of consecutive trading days | d			30
Debt discount recorded in additional paid-in-capital			$ 32,637
Issuance costs attributable to liability component			3,600
Issuance costs attributable to equity component			$ 1,100
Class A Common Stock
Debt Instrument [Line Items]
Debt instrument shares issuable upon conversion | shares			1,928,417
Initial strike price | $ / shares			39.29
Cap price | $ / shares			60.44
Cost of purchased capped calls			$ 17,100
Closing Price of common stock | $ / shares			$ 36.20
LIBOR | Interest Rate Swap
Debt Instrument [Line Items]
Derivative contract term		5 years
Minimum
Debt Instrument [Line Items]
Number of trading days | d			20
Conversion Condition One
Debt Instrument [Line Items]
Number of consecutive trading days | d			30
Minimum percentage of conversion price			130.00%
Conversion Condition One | Minimum
Debt Instrument [Line Items]
Number of trading days | d			20
Conversion Condition Two
Debt Instrument [Line Items]
Number of consecutive trading days | d			5
Number of business days			5 days
Notes measurement maximum percentage			98.00%
Convertible Debt
Debt Instrument [Line Items]
Convertible senior notes	$ 143,800	$ 143,800	$ 143,750
Convertible senior notes percentage	0.875%	0.875%
Debt instrument due date	Apr. 1, 2023
Debt instrument, description	Interest is payable semi-annually in arrears on April 1 and October 1 of each year, commencing on October 1, 2018.
Convertible notes redemption period			Apr. 5, 2021
Number of trading days to provide notice of redemption			3 days
Redemption price, percentage			100.00%
Number of sinking fund provided for notes | SinkingFund			0
6.34% Convertible Notes
Debt Instrument [Line Items]
Estimated implied interest rate on notes			6.34%
Fair value of liability component			$ 110,000
Debt discount recorded in additional paid-in-capital			$ 33,800

Convertible Senior Notes - Comp

Convertible Senior Notes - Components of Notes (Details) - USD ($) $ in Thousands	Jun. 30, 2018	Mar. 31, 2018
Liability component:
Net carrying amount	$ 108,153
Equity component	32,637
Convertible Debt
Liability component:
Convertible senior notes	143,750	$ 143,800
Less: debt discount, net of amortization	$ (35,597)

Convertible Senior Notes - Co50

Convertible Senior Notes - Components of Notes (Parenthetical) (Details) $ in Millions	6 Months Ended
	Jun. 30, 2018USD ($)
Debt Disclosure [Abstract]
Issuance costs attributable to equity component	$ 1.1

Convertible Senior Notes - Inte

Convertible Senior Notes - Interest Expense Recognized Related to Notes (Details) $ in Thousands	6 Months Ended
	Jun. 30, 2018USD ($)
Debt Disclosure [Abstract]
Contractual interest expense	$ 350
Amortization of debt discount	1,598
Amortization of issuance costs	176
Total interest expense	$ 2,124

Convertible Senior Notes - Fair

Convertible Senior Notes - Fair Value and Carrying Value of Convertible Senior Notes (Details) $ in Thousands	Jun. 30, 2018USD ($)
Convertible senior notes, Fair Value
Debt Instrument [Line Items]
Convertible senior notes, Fair Value	$ 160,820
Convertible senior notes, Carrying Value
Debt Instrument [Line Items]
Convertible senior notes, Fair Value	$ 108,153

Stockholders' Equity - Addition

Stockholders' Equity - Additional Information (Details)	6 Months Ended
	Jun. 30, 2018$ / sharesshares
Class Of Stock [Line Items]
Preferred stock, shares authorized	5,000,000
Preferred stock, par value | $ / shares	$ 0.0001
Preferred stock, shares outstanding	0
Number of shares issued for conversion	3,700,000
Class A Common Stock
Class Of Stock [Line Items]
Common stock, shares authorized	451,000,000
Common stock, par value | $ / shares	$ 0.0001
Common stock, shares issued	44,567,831
Common stock, shares outstanding	44,567,831
Common stock, entitled for voting rights	one vote per share
Number of shares issued for conversion	1,928,417
Class B Common Stock
Class Of Stock [Line Items]
Common stock, shares authorized	7,713,740
Common stock, par value | $ / shares	$ 0.0001
Common stock, shares outstanding	0
Percentage of outstanding common stock, minimum	25.00%
Number of shares converted	1,928,417
Number of Class B common stock converted to Class A common stock as a result of ceasing to represent minimum threshold	9,195,917
Treasury stock retired	36,286,260
Number of shares authorized prior to conversion	44,000,000

Warrants - Additional Informati

Warrants - Additional Information (Details) - shares	Jun. 30, 2018	Mar. 08, 2018
Class B Common Stock
Class Of Warrant Or Right [Line Items]
Warrants issued to purchase shares		10,604
Common stock issued through cashless exercise of warrant		5,532
Common Stock
Class Of Warrant Or Right [Line Items]
Warrants outstanding	0

Equity Incentive Plans - Additi

Equity Incentive Plans - Additional Information (Details) $ in Millions	3 Months Ended	6 Months Ended
	Jun. 30, 2018USD ($)shares	Jun. 30, 2018USD ($)shares
Stock Option
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Unrecognized compensation cost | $	$ 10.1	$ 10.1
Weighted-average remaining expected term		1 year 10 months 24 days
RSU
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Weighted-average remaining expected term		3 years 3 months 18 days
Unrecognized compensation cost | $	$ 55.1	$ 55.1
2016 Equity Incentive Plan
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Shares available for future issuance	5,629,839	5,629,839
Automatically increase percentage of shares of all classes of company's common stock outstanding	5.00%	5.00%
2016 Equity Incentive Plan | Minimum
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Automatically increase of shares reserved for issuance	5,500,000	5,500,000
2016 Employee Stock Purchase Plan
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Automatically increase percentage of shares of all classes of company's common stock outstanding	1.00%	1.00%
2016 Employee Stock Purchase Plan | Class A Common Stock
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Shares available for future issuance	1,117,643	1,117,643
Automatically increase of shares reserved for issuance	1,600,000	1,600,000
Purchase price of common stock, percent		85.00%
Number of shares purchased	125,121	125,121

Equity Incentive Plans - Summar

Equity Incentive Plans - Summary of Stock Option Activity (Details) - Stock Option $ / shares in Units, $ in Thousands	6 Months Ended
	Jun. 30, 2018USD ($)$ / sharesshares
Options Outstanding
Outstanding at beginning of period | shares	7,490,000
Options exercised | shares	(1,747,000)
Options forfeited or canceled | shares	(224,000)
Outstanding at end of period | shares	5,519,000
Vested and expected to vest at end of period | shares	5,390,000
Exercisable at end of period | shares	3,804,000
Weighted Average Exercise Price per Share
Outstanding at beginning of period | $ / shares	$ 10.76
Options exercised | $ / shares	7.98
Options forfeited or canceled | $ / shares	15.36
Outstanding at end of period | $ / shares	11.46
Vested and expected to vest at end of period | $ / shares	11.38
Exercisable at end of period | $ / shares	$ 9.90
Share-based Compensation Arrangement by Share-based Payment Award, Options, Additional Disclosures [Abstract]
Outstanding	6 years 3 months 29 days
Vested and expected to vest at end of period	6 years 3 months 14 days
Exercisable at end of period	5 years 7 months 17 days
Total Intrinsic Value | $	$ 136,542
Vested and expected to vest at end of period | $	133,804
Exercisable at end of period | $	$ 100,037

Equity Incentive Plans - Summ57

Equity Incentive Plans - Summary of RSU Activity Under 2016 Plan (Details) - RSU shares in Thousands	6 Months Ended
	Jun. 30, 2018$ / sharesshares
RSU Outstanding
Non-Vested outstanding at beginning period | shares	2,030
Granted | shares	1,124
Vested | shares	(400)
Forfeited or canceled | shares	(187)
Non-Vested outstanding at end of period | shares	2,567
Weighted-Average Grant Date Fair Value per Share
Non-Vested outstanding at begging period | $ / shares	$ 16.15
Granted | $ / shares	31.37
Vested | $ / shares	14.84
Forfeited or canceled | $ / shares	18.42
Non-Vested outstanding at end of period | $ / shares	$ 22.85

Equity Incentive Plans - Summ58

Equity Incentive Plans - Summary of Stock Based Compensation Expenses (Details) - USD ($) $ in Thousands	3 Months Ended		6 Months Ended
	Jun. 30, 2018	Jun. 30, 2017	Jun. 30, 2018	Jun. 30, 2017
Employee Service Share Based Compensation Allocation Of Recognized Period Costs [Line Items]
Stock-based compensation	$ 5,579	$ 3,685	$ 10,531	$ 7,310
Cost of Revenue Subscription
Employee Service Share Based Compensation Allocation Of Recognized Period Costs [Line Items]
Stock-based compensation	289	240	608	597
Cost of Revenue Professional Services
Employee Service Share Based Compensation Allocation Of Recognized Period Costs [Line Items]
Stock-based compensation	479	230	807	548
Research and Development
Employee Service Share Based Compensation Allocation Of Recognized Period Costs [Line Items]
Stock-based compensation	1,399	1,112	2,792	2,153
Sales and Marketing
Employee Service Share Based Compensation Allocation Of Recognized Period Costs [Line Items]
Stock-based compensation	1,706	1,077	3,136	2,077
General and Administrative
Employee Service Share Based Compensation Allocation Of Recognized Period Costs [Line Items]
Stock-based compensation	$ 1,706	$ 1,026	$ 3,188	$ 1,935

Deferred Revenue and Performa59

Deferred Revenue and Performance Obligations - Summary of Deferred Revenue Balances (Details) $ in Thousands	6 Months Ended
	Jun. 30, 2018USD ($)
Deferred Revenue Arrangement [Line Items]
Deferred revenue balance at December 31, 2017	$ 119,301
Revenue recognized during the period	(110,501)
Additions to deferred revenue during the period, including deferred revenue acquired	115,568
Deferred revenue balance at June 30, 2018	124,368
Subscription
Deferred Revenue Arrangement [Line Items]
Deferred revenue balance at December 31, 2017	110,934
Revenue recognized during the period	(94,677)
Additions to deferred revenue during the period, including deferred revenue acquired	98,095
Deferred revenue balance at June 30, 2018	114,352
Services
Deferred Revenue Arrangement [Line Items]
Deferred revenue balance at December 31, 2017	8,367
Revenue recognized during the period	(15,824)
Additions to deferred revenue during the period, including deferred revenue acquired	17,473
Deferred revenue balance at June 30, 2018	$ 10,016

Deferred Revenue and Performa60

Deferred Revenue and Performance Obligations - Additional Information (Details) - USD ($) $ in Millions	3 Months Ended		6 Months Ended
	Jun. 30, 2018	Jun. 30, 2017	Jun. 30, 2018	Jun. 30, 2017
Deferred Revenue Arrangement [Line Items]
Percentage of revenue expected to be recognized from remaining performance obligation			90.00%
Revenue, remaining performance obligation, expected timing of satisfaction, period	24 months		24 months
Subscription
Deferred Revenue Arrangement [Line Items]
Recognition of deferred revenue	$ 44.7	$ 34.5	$ 74	$ 61.1
Revenue expected to be recognized from remaining performance obligation	226.9		226.9
Professional Services
Deferred Revenue Arrangement [Line Items]
Recognition of deferred revenue	2.4	$ 1.6	5.3	$ 4.4
Revenue expected to be recognized from remaining performance obligation	$ 12.1		$ 12.1

Net Loss Per Share Attributab61

Net Loss Per Share Attributable to Common Stockholders - Computation of Basic and Diluted Net Loss Per Share (Details) - USD ($) $ / shares in Units, shares in Thousands, $ in Thousands	3 Months Ended		6 Months Ended
	Jun. 30, 2018	Jun. 30, 2017	Jun. 30, 2018	Jun. 30, 2017
Numerator:
Net loss attributable to common stockholders	$ (5,297)	$ (6,912)	$ (13,396)	$ (14,051)
Denominator:
Weighted-average common shares outstanding - basic and diluted	43,921	39,175	43,345	38,793
Net loss per common share - basic and diluted	$ (0.12)	$ (0.18)	$ (0.31)	$ (0.36)

Net Loss Per Share Attributab62

Net Loss Per Share Attributable to Common Stockholders - Schedule of Antidilutive Securities Excluded from Computation of Diluted Net Loss Per Share (Details) - shares shares in Thousands	3 Months Ended		6 Months Ended
	Jun. 30, 2018	Jun. 30, 2017	Jun. 30, 2018	Jun. 30, 2017
Antidilutive Securities Excluded From Computation Of Earnings Per Share [Line Items]
Antidilutive securities excluded from computation of diluted net loss per share	12,019	11,654	10,764	11,795
Common Stock Issuable under 2016 ESPP
Antidilutive Securities Excluded From Computation Of Earnings Per Share [Line Items]
Antidilutive securities excluded from computation of diluted net loss per share	122	212	127	231
Stock Options to Purchase Common Stock
Antidilutive Securities Excluded From Computation Of Earnings Per Share [Line Items]
Antidilutive securities excluded from computation of diluted net loss per share	5,993	10,145	6,463	10,587
Unvested Restricted Stock Units (RSUs)
Antidilutive Securities Excluded From Computation Of Earnings Per Share [Line Items]
Antidilutive securities excluded from computation of diluted net loss per share	2,389	1,286	2,228	966
Warrants to Purchase Common Stock
Antidilutive Securities Excluded From Computation Of Earnings Per Share [Line Items]
Antidilutive securities excluded from computation of diluted net loss per share		11	4	11
Convertible Senior Notes
Antidilutive Securities Excluded From Computation Of Earnings Per Share [Line Items]
Antidilutive securities excluded from computation of diluted net loss per share	3,515		1,942

Segments - Additional Informati

Segments - Additional Information (Details) - Segment	3 Months Ended		6 Months Ended
	Jun. 30, 2018	Jun. 30, 2017	Jun. 30, 2018	Jun. 30, 2017
Segment Reporting Information [Line Items]
Number of operating segment			1
North America | Revenue | Geographic Concentration Risk
Segment Reporting Information [Line Items]
Percentage of revenue attributable to United States	99.00%	100.00%	98.00%	99.00%

Segments - Summary of Revenue b

Segments - Summary of Revenue by Geographic Areas (Details) - USD ($) $ in Thousands	3 Months Ended		6 Months Ended
	Jun. 30, 2018	Jun. 30, 2017	Jun. 30, 2018	Jun. 30, 2017
Revenues From External Customers And Long Lived Assets [Line Items]
Revenue	$ 59,045	$ 45,225	$ 113,115	$ 89,156
Americas
Revenues From External Customers And Long Lived Assets [Line Items]
Revenue	40,283	32,630	77,874	64,540
EMEA
Revenues From External Customers And Long Lived Assets [Line Items]
Revenue	15,561	10,492	28,747	20,542
APAC
Revenues From External Customers And Long Lived Assets [Line Items]
Revenue	$ 3,201	$ 2,103	$ 6,494	$ 4,074