LivePerson (LPSN) 10-K 2 Mar 20 2019 FY Annual report Financial data

Cover Page

Cover Page - USD ($)	12 Months Ended
	Dec. 31, 2019	Feb. 24, 2020	Jun. 30, 2019
Cover page.
Document Type	10-K
Document Annual Report	true
Document Period End Date	Dec. 31, 2019
Document Transition Report	false
Entity File Number	000-30141
Entity Registrant Name	LIVEPERSON, INC.
Entity Central Index Key	0001102993
Current Fiscal Year End Date	--12-31
Document Fiscal Year Focus	2019
Document Fiscal Period Focus	FY
Amendment Flag	false
Entity Incorporation, State or Country Code	DE
Entity Tax Identification Number	13-3861628
Entity Address, Address Line One	475 Tenth Avenue, 5th Floor
Entity Address, City or Town	New York
Entity Address, State or Province	NY
Entity Address, Postal Zip Code	10018
City Area Code	212
Local Phone Number	609-4200
Title of 12(b) Security	Common Stock, par value $0.001 per share
Trading Symbol	LPSN
Security Exchange Name	NASDAQ
Entity Well-known Seasoned Issuer	No
Entity Voluntary Filers	No
Entity Current Reporting Status	Yes
Entity Interactive Data Current	Yes
Entity Filer Category	Large Accelerated Filer
Entity Small Business	false
Entity Emerging Growth Company	false
Entity Shell Company	false
Entity Public Float			$ 1,207,203,816
Entity Common Stock, Shares Outstanding		64,108,516
Documents Incorporated by Reference	Portions of the registrant’s definitive proxy statement for the 2020 Annual Meeting of Stockholders, which we plan to file subsequent to the date hereof, are incorporated by reference into Items 10, 11, 12, 13 and 14 of Part III of this Form 10-K.

Consolidated Balance Sheets

Consolidated Balance Sheets - USD ($) $ in Thousands	Dec. 31, 2019	Dec. 31, 2018
CURRENT ASSETS:
Cash and cash equivalents	$ 176,523	$ 66,449
Accounts receivable, net of allowance for doubtful accounts of $3,070 and $2,276, in 2019 and 2018, respectively	87,620	46,023
Prepaid expenses and other current assets	13,964	9,252
Total current assets	278,107	121,724
Operating lease right of use asset	15,680
Property and equipment, net	76,236	43,735
Contract acquisition costs	31,965	13,361
Intangibles, net	11,812	13,832
Goodwill	94,987	95,031
Deferred tax assets	2,179	713
Other assets	1,744	1,707
Total assets	512,710	290,103
CURRENT LIABILITIES:
Accounts payable	12,302	8,174
Accrued expenses and other current liabilities	62,778	50,662
Deferred revenue	88,751	55,015
Operating lease liability	6,602
Total current liabilities	170,433	113,851
Deferred revenue, net of current portion	438	222
Convertible senior notes, net	179,012	0
Other liabilities	72	4,205
Operating lease liability, net of current portion	12,865
Deferred tax liability	1,355	1,096
Total liabilities	364,175	119,374
Commitments and contingencies (See Note 9)
STOCKHOLDERS' EQUITY:
Preferred stock, $0.001 par value - 5,000,000 shares authorized, none issued	0	0
Common stock, $0.001 par value - 200,000,000 and 100,000,000 shares authorized, 66,543,073 and 63,676,229 shares issued, and 63,833,243 and 60,994,944 shares outstanding as of December 31, 2019 and 2018, respectively	67	64
Additional paid-in capital	436,557	362,590
Treasury stock, at cost; 2,709,830 and 2,681,285 shares respectively	(3)	(3)
Accumulated deficit	(283,562)	(187,491)
Accumulated other comprehensive loss	(4,524)	(4,431)
Total stockholders’ equity	148,535	170,729
Total liabilities and stockholders’ equity	$ 512,710	$ 290,103

Consolidated Balance Sheets (Pa

Consolidated Balance Sheets (Parenthetical) - USD ($) $ in Thousands	Dec. 31, 2019	Dec. 31, 2018
Statement of Financial Position [Abstract]
Accounts receivable, allowance for doubtful accounts	$ 3,070	$ 2,276
Preferred stock, par value (in dollars per share)	$ 0.001	$ 0.001
Preferred stock, shares authorized (in shares)	5,000,000	5,000,000
Preferred stock, shares issued (in shares)	0	0
Common stock, par value (in dollars per share)	$ 0.001	$ 0.001
Common stock, shares authorized (in shares)	200,000,000	100,000,000
Common stock, shares issued (in shares)	66,543,073	63,676,229
Common stock, shares outstanding (in shares)	63,833,243	60,994,944
Treasury stock, at cost (in shares)	2,709,830	2,681,285

Consolidated Statements of Oper

Consolidated Statements of Operations - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2019	Dec. 31, 2018	Dec. 31, 2017
Revenue	$ 291,609	$ 249,838	$ 218,876
Costs and expenses:
Cost of revenue	78,878	62,479	58,205
Sales and marketing	156,814	103,344	90,905
General and administrative	56,967	45,873	43,124
Product development	82,145	55,707	40,034
Restructuring costs	2,043	4,468	2,594
Amortization of purchased intangibles	1,794	1,670	1,840
Total costs and expenses	378,641	273,541	236,702
Loss from operations	(87,032)	(23,703)	(17,826)
Other (expense) income, net
Interest (expense) income	(7,407)	22	26
Other income (expense), net	1,213	(493)	110
Total Other (expense) income, net	(6,194)	(471)	136
Loss before provision for income taxes	(93,226)	(24,174)	(17,690)
Provision for income taxes	2,845	858	501
Net loss	$ (96,071)	$ (25,032)	$ (18,191)
Net loss per share of common stock:
Basic (in dollars per share)	$ (1.53)	$ (0.42)	$ (0.32)
Diluted (in dollars per share)	$ (1.53)	$ (0.42)	$ (0.32)
Weighted-average shares used to compute net loss income per share:
Basic (in shares)	62,593,026	59,203,400	56,358,017
Diluted (in shares)	62,593,026	59,203,400	56,358,017
Additional information on costs and expenses:
Stock compensation expense	$ 44,105	$ 14,841	$ 8,944
Depreciation and amortization expense	16,366	14,188	12,358
Cost of revenue
Additional information on costs and expenses:
Stock compensation expense	4,218	996	448
Depreciation and amortization expense	8,557	7,831	7,150
Amortization of purchased intangibles	1,138	1,143	2,842
Sales and marketing
Additional information on costs and expenses:
Stock compensation expense	10,010	5,374	2,500
Depreciation and amortization expense	1,642	1,520	1,625
General and administrative
Additional information on costs and expenses:
Stock compensation expense	12,216	4,921	3,691
Depreciation and amortization expense	908	1,083	1,226
Product development
Additional information on costs and expenses:
Stock compensation expense	17,661	3,550	2,305
Depreciation and amortization expense	$ 5,259	$ 3,754	$ 2,357

Consolidated Statements of Comp

Consolidated Statements of Comprehensive Loss - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2019	Dec. 31, 2018	Dec. 31, 2017
Statement of Comprehensive Income [Abstract]
Net loss	$ (96,071)	$ (25,032)	$ (18,191)
Foreign currency translation adjustment	(93)	(1,896)	3,625
Comprehensive loss	$ (96,164)	$ (26,928)	$ (14,566)

Consolidated Statements of Stoc

Consolidated Statements of Stockholders' Equity - USD ($) $ in Thousands	Total	Common Stock	Treasury Stock	Additional Paid-In Capital	Accumulated Deficit	Accumulated Other Comprehensive Loss
Beginning Balance (in shares) at Dec. 31, 2016		58,276,447	(2,340,105)
Beginning Balance at Dec. 31, 2016	$ 138,476	$ 58	$ (2)	$ 289,524	$ (144,944)	$ (6,160)
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Common stock issued upon exercise of stock options (in shares)	854,000	853,885
Common stock issued upon exercise of stock options	$ 7,491	$ 1		7,490
Common stock issued upon vesting of restricted stock units (in shares)		363,429
Common stock issued upon vesting of restricted stock units	1	$ 1
Stock-based compensation	8,944			8,944
Common stock issued under Employee Stock Purchase Plan (in shares)		170,208
Common stock issued under Employee Stock Purchase Plan	1,459			1,459
Common stock repurchase (in shares)			(247,430)
Common stock repurchase	(1,742)		$ (1)	(1,741)
Net loss	(18,191)				(18,191)
Other comprehensive income (loss)	3,625					3,625
Ending Balance (in shares) at Dec. 31, 2017		59,663,969	(2,587,535)
Ending Balance at Dec. 31, 2017	$ 140,063	$ 60	$ (3)	305,676	(163,135)	(2,535)
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Common stock issued upon exercise of stock options (in shares)	3,120,000	3,120,404
Common stock issued upon exercise of stock options	$ 32,791	$ 3		32,788
Common stock issued upon vesting of restricted stock units (in shares)		361,539
Common stock issued upon vesting of restricted stock units	1	$ 1
Stock-based compensation	14,841			14,841
Common stock issued under Employee Stock Purchase Plan (in shares)		150,989
Common stock issued under Employee Stock Purchase Plan	2,480			2,480
Common stock repurchase (in shares)			(93,750)
Common stock repurchase	(1,345)		$ 0	(1,345)
ASC 606 prior period adjustment	676				676
Issuance of common stock in connection with acquisitions (in shares)		379,328
Issuance of common stock in connection with acquisitions	8,150			8,150
Net loss	(25,032)				(25,032)
Other comprehensive income (loss)	(1,896)					(1,896)
Ending Balance (in shares) at Dec. 31, 2018		63,676,229	(2,681,285)
Ending Balance at Dec. 31, 2018	$ 170,729	$ 64	$ (3)	362,590	(187,491)	(4,431)
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Common stock issued upon exercise of stock options (in shares)	1,523,000	1,523,018
Common stock issued upon exercise of stock options	$ 16,918	$ 2		16,916
Common stock issued upon vesting of restricted stock units (in shares)		1,197,576
Common stock issued upon vesting of restricted stock units	1,000	$ 1		999
Stock-based compensation	25,083			25,083
Common stock issued under Employee Stock Purchase Plan (in shares)		146,250
Common stock issued under Employee Stock Purchase Plan	4,142			4,142
Common stock repurchase (in shares)			(28,545)
Common stock repurchase	(903)		$ 0	(903)
Equity component of convertible senior notes	52,900			52,900
Equity component of convertible senior notes issuance costs	(1,986)			(1,986)
Purchase of capped call option	(23,184)			(23,184)
Net loss	(96,071)				(96,071)
Other comprehensive income (loss)	(93)					(93)
Ending Balance (in shares) at Dec. 31, 2019		66,543,073	(2,709,830)
Ending Balance at Dec. 31, 2019	$ 148,535	$ 67	$ (3)	$ 436,557	$ (283,562)	$ (4,524)

Consolidated Statements of Cash

Consolidated Statements of Cash Flows - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2019	Dec. 31, 2018	Dec. 31, 2017
OPERATING ACTIVITIES:
Net loss	$ (96,071)	$ (25,032)	$ (18,191)
Adjustments to reconcile net loss to net cash (used in) provided by operating activities:
Stock-based compensation expense	44,105	14,841	8,944
Depreciation and amortization	16,366	14,188	12,358
Amortization of tenant allowance	(516)	(326)	(166)
Amortization of purchased intangibles	2,932	2,813	4,682
Amortization of debt issuance costs	956	0	0
Accretion of debt discount on convertible senior notes	7,605	0	0
Change in fair value of contingent consideration	(328)	0	0
Provision for doubtful accounts, net	2,159	1,788	1,895
Deferred income taxes	(1,207)	(309)	(2,397)
Changes in operating assets and liabilities, net of acquisitions:
Accounts receivable	(43,757)	(9,662)	(7,998)
Prepaid expenses and other current assets	(4,712)	(12,993)	9,270
Contract acquisition costs noncurrent	(13,718)	(1,635)	(11,137)
Other assets	(30)	(107)	(38)
Accounts payable	3,808	2,199	(2,743)
Accrued expenses and other current liabilities	(10,882)	(205)	7,838
Deferred revenue	33,953	19,005	8,418
Increase in operating lease liability	388	0	0
Other liabilities	(209)	214	(445)
Net cash (used in) provided by operating activities	(59,158)	4,779	10,290
INVESTING ACTIVITIES:
Purchases of property and equipment, including capitalized software	(47,582)	(21,938)	(17,390)
Payments for acquisitions and intangible assets, net of cash acquired	(924)	(7,286)	(441)
Cash held as collateral	0	1,451	2,511
Net cash used in investing activities	(48,506)	(27,773)	(15,320)
FINANCING ACTIVITIES:
Repurchase of common stock	(903)	(1,345)	(1,742)
Proceeds from issuance of common stock in connection with the exercise of options and ESPP	21,060	35,271	8,951
Proceeds from issuance of convertible senior notes	230,000	0	0
Payment of issuance costs in connection with convertible senior notes	(8,635)	0	0
Payment related to contingent consideration	(487)	0	0
Purchase of capped call option	(23,184)	0	0
Net cash provided by financing activities	217,851	33,926	7,209
EFFECT OF FOREIGN EXCHANGE RATE CHANGES ON CASH AND CASH EQUIVALENTS	(113)	(598)	3,047
CHANGE IN CASH AND CASH EQUIVALENTS	110,074	10,334	5,226
CASH AND CASH EQUIVALENTS - Beginning of the year	66,449	56,115	50,889
CASH AND CASH EQUIVALENTS - End of the year	176,523	66,449	56,115
SUPPLEMENTAL DISCLOSURE OF OTHER CASH FLOW INFORMATION:
Cash paid for income taxes	3,304	5,144	1,551
SUPPLEMENTAL DISCLOSURE OF NON-CASH INVESTING AND FINANCING ACTIVITIES:
Purchase of property and equipment recorded in accounts payable	1,198	190	936
Leasehold improvements funded by landlord	0	1,551	0
Operating lease right of use asset (1)	21,588
Operating lease liabilities- short-term and long term	(19,467)
Conversable Dec 13 2019
SUPPLEMENTAL DISCLOSURE OF NON-CASH INVESTING AND FINANCING ACTIVITIES:
Issuance of shares of common stock in connection with acquisition	$ 1,000	0	0
Issuance of shares of common stock in connection with acquisition (in shares)	38,462
BotCentral
SUPPLEMENTAL DISCLOSURE OF NON-CASH INVESTING AND FINANCING ACTIVITIES:
Issuance of shares of common stock in connection with acquisition	$ 0	$ 1,000	0
Issuance of shares of common stock in connection with acquisition (in shares)		85,861
Conversable Sep 27 2018
SUPPLEMENTAL DISCLOSURE OF NON-CASH INVESTING AND FINANCING ACTIVITIES:
Issuance of shares of common stock in connection with acquisition	0	$ 2,850	0
Issuance of shares of common stock in connection with acquisition (in shares)		115,385
Conversable Inc
SUPPLEMENTAL DISCLOSURE OF NON-CASH INVESTING AND FINANCING ACTIVITIES:
Fair value of contingent earn-out in connection with the acquisition recorded in accrued expenses	0	$ 1,496	0
AdvantageTec
SUPPLEMENTAL DISCLOSURE OF NON-CASH INVESTING AND FINANCING ACTIVITIES:
Issuance of shares of common stock in connection with acquisition	0	$ 4,300	0
Issuance of shares of common stock in connection with acquisition (in shares)		178,082
Fair value of contingent earn-out in connection with the acquisition recorded in accrued expenses	$ 0	$ 876	$ 0

Description of Business and Sum

Description of Business and Summary of Significant Accounting Policies	12 Months Ended
	Dec. 31, 2019
Accounting Policies [Abstract]
Description of Business and Summary of Significant Accounting Policies	Description of Business and Summary of Significant Accounting Policies LivePerson, Inc. (“LivePerson”, the “Company”, “we” or “our”) was incorporated in the State of Delaware in November 1995 and the LivePerson service was introduced in November 1998. In April 2000, the company completed an initial public offering and is currently traded on the NASDAQ Global Select Market and the Tel Aviv Stock Exchange. LivePerson is headquartered in New York City with U.S. offices in Alpharetta (Georgia), Austin (Texas), San Francisco (California) and Seattle (Washington), and international offices in Amsterdam (Netherlands), Berlin (Germany), Delhi (India), London (United Kingdom), Mannheim (Germany), Melbourne (Australia), Milan (Italy), Paris (France), Ra'anana (Israel), Reading (United Kingdom), Singapore (Singapore), Tel Aviv (Israel), and Tokyo (Japan). LivePerson makes life easier for people and brands everywhere through messaging powered by AI and humans. During the past decade, the consumer has made the mobile device the center of their digital lives, and they have made mobile messaging the center of communication with friends, family and peers. Our technology enables consumers to connect with businesses through these same preferred conversational interfaces, including Facebook Messenger, SMS, WhatsApp, Apple Business Chat, Google Rich Business Messenger and Alexa. These messaging conversations harness human agents, bots and Artificial Intelligence (AI) to power convenient, personalized and content-rich journeys across the entire consumer lifecycle, from discovery and research, to sales, service and support, and even marketing, social and brick and mortar engagements. For example, consumers can look up product info like ratings, images and pricing, search for stores, see product inventory, schedule appointments, apply for credit, approve repairs, make purchases or payments - all without ever leaving the messaging channel. These AI and human-assisted conversational experiences constitute the Conversational Space. LiveEngage, our enterprise-class cloud-based platform, enables businesses to become conversational by securely deploying messaging, coupled with bots and AI, at scale for brands with tens of millions of customers and many thousands of customer care agents. LiveEngage powers conversations across each of a brand’s primary digital channels, including mobile apps, mobile and desktop web browsers, short message service (SMS), social media and third-party consumer messaging platforms. Brands can also use LiveEngage to message consumers when they dial a 1-800 number instead of forcing them to navigate interactive voice response systems (IVRs) and wait on hold. Similarly, LiveEngage can ingest traditional emails and convert them into messaging conversations, or embed messaging conversations directly into web advertisements, rather than redirect consumers to static website landing pages. LivePerson's robust, cloud-based suite of rich messaging, real-time chat, AI and automation offerings features consumer and agent facing bots, intelligent routing and capacity mapping, real-time intent detection and analysis, queue prioritization, customer sentiment, analytics and reporting, content delivery, Payment Card Industry (PCI) compliance, cobrowsing and a sophisticated proactive targeting engine. With LiveEngage, agents can manage all conversations with consumers through a single console interface, regardless of which disparate messaging endpoints the consumers originate from; i.e., WhatsApp, Line, Apple Business Chat, IVR, social, email, Amazon Alexa, or WeChat. An extensible application programming interface (API) stack facilitates a lower cost of ownership by facilitating robust integration into back-end systems, as well as enabling developers to build their own programs and services on top of the platform. More than 40 APIs and software development kits are available on LiveEngage. LivePerson’s Conversational AI offerings put the power of bot development, training, management and analysis into the hands of the contact center and its agents, the teams most familiar with how to structure sales and service conversations to drive successful outcomes. The platform enables what we call “the tango” of humans, AI and bots, whereby human agents act as bot managers, overseeing AI-powered conversations and seamlessly stepping into the flow when a personal touch is needed. Agents become ultra-efficient, leveraging the AI engine to serve up relevant content, define next-best actions and take over repetitive transactional work, so that the agent can focus on relationship building. By seamlessly integrating messaging with our proprietary Conversational AI, as well as third-party bots, LiveEngage offers brands a comprehensive approach to scaling automations across their millions of customer conversations. LivePerson's consumer services offering is an online marketplace that connects independent service providers (Experts) who provide information and knowledge for a fee via mobile and online messaging with individual consumers (Users). Users seek assistance and advice in various categories including personal counseling and coaching, computers and programming, education and tutoring, spirituality and religion, and other topics. Principles of Consolidation The consolidated financial statements reflect the operations of LivePerson and its wholly-owned subsidiaries. All significant intercompany balances and transactions have been eliminated in consolidation. Use of Estimates The preparation of the consolidated financial statements in accordance with accounting principles generally accepted in the United States of America (“GAAP”) requires the Company’s management to make a number of estimates and assumptions relating to the reported amounts of assets and liabilities, 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 period. Significant items subject to such estimates and assumptions include revenue recognition, stock-based compensation, accounts receivable, the valuation of goodwill and intangible assets, income taxes and legal contingencies. Actual results could differ from those estimates. Concentration of Credit Risk Financial instruments that potentially subject the Company to significant concentrations of credit risk consist primarily of cash and cash equivalents and accounts receivable which approximate fair value at December 31, 2019 because of the short-term nature of these instruments. The Company invests its cash and cash equivalents with financial institutions that it believes are of high quality, and the Company performs periodic evaluations of these instruments and the relative credit standings of the institutions with which it invests. At certain times, the Company’s cash balances with any one financial institution may exceed Federal Deposit Insurance Corporation insurance limits. The Company believes it mitigates its risk by depositing its cash balances with high credit, quality financial institutions. The Company performs ongoing credit evaluations of its customers’ financial condition (except for customers who purchase the LivePerson services by credit card via Internet download) and has established an allowance for doubtful accounts based upon factors surrounding the credit risk of customers, historical trends and other information. Concentration of credit risk is limited due to the Company’s large number of customers. No single customer accounted for or exceeded 10% of revenue in 2019 , 2018 or 2017 . Two customers exceeded 10% of the Company's total accounts receivable in 2019 with a balance of approximately $17.6 million . No single customer accounted for or exceeded 10% of the Company’s total accounts receivable in 2018 or in 2017. Foreign Currency Translation The Company’s operations are conducted in various countries around the world and the financial statements of its foreign subsidiaries are reported in the applicable foreign currencies (functional currencies). Financial information is translated from the applicable functional currency to the U.S. dollar (the reporting currency) for inclusion in the Company’s consolidated financial statements. Income, expenses and cash flows are translated at weighted average exchange rates prevailing during the fiscal period, and assets and liabilities are translated at fiscal period-end exchange rates. Resulting translation adjustments are included as a component of accumulated other comprehensive income (loss) in stockholders’ equity. Foreign exchange transaction gain or losses are included in Other Income (Expense), net in the accompanying consolidated statements of operations. Cash and Cash Equivalents The Company considers all highly liquid securities with original maturities of three months or less when acquired to be cash equivalents. Cash equivalents, which primarily consist of money market funds, are recorded at cost, which approximates fair value. Accounts Receivable Accounts receivable are recorded at the invoiced amount and do not bear interest. The allowance for doubtful accounts is the Company’s best estimate of the amount of probable credit losses in the Company’s existing accounts receivable. The Company determines the allowance based on historical write-off experience. The Company reviews its allowance for doubtful accounts monthly. Past due balances over 90 days and over a specified amount are reviewed individually for collectability. All other balances are reviewed on a pooled basis. Account balances are charged off against the allowance after all means of collection have been exhausted and the potential for recovery is considered remote. The Company does not have any off-balance sheet credit exposure related to its customers. The activity in the allowance for doubtful accounts is as follows (amounts in thousands): Year Ended December 31, Beginning Balance Additions Charged to Costs and Expenses Deductions / Write-Offs Ending Balance 2017 $ 1,732 $ 1,895 $ (2,309 ) $ 1,318 2018 $ 1,318 $ 1,814 $ (856 ) $ 2,276 2019 $ 2,276 $ 2,159 $ (1,365 ) $ 3,070 Property and Equipment Property and equipment are stated at cost, net of accumulated depreciation, and amortization. Depreciation and amortization is calculated using the straight-line method over the estimated useful lives of the related assets, generally three to five years for equipment and software. Leasehold improvements are amortized using the straight-line method over the shorter of the lease term or the estimated useful life of the asset. Depreciation expense, which includes amortization of internal use software totaled $16.4 million , $14.2 million , and $12.4 million for the years ended December 31, 2019 , 2018 and 2017 , respectively. Internal-Use Software Development Costs In accordance with the Financial Accounting Standards Board (“FASB”) Accounting Standards Codification (“ASC”) 350-40, ‘‘Internal-Use Software’’, the Company capitalizes its costs to develop its internal use software when preliminary development efforts are successfully completed, management has authorized and committed project funding, and it is probable that the project will be completed and the software will be used as intended. These costs are included in property and equipment in the Company's consolidated balance sheets and are amortized on a straight-line basis over the estimated useful life of the related asset, which approximates five years . Costs incurred prior to meeting these criteria, together with costs incurred for training and maintenance, are expensed as incurred. The Company capitalized internal-use software costs of $29.1 million , $11.7 million , and $8.3 million for the years ended December 31, 2019 , 2018 and 2017 , respectively. Goodwill and Intangible Assets The Company records goodwill when the consideration paid in a business combination exceeds the fair value of the net tangible assets and the identified intangible assets acquired. Goodwill is not amortized, but instead is required to be tested for impairment annually and whenever events or changes in circumstances indicate that the carrying value of goodwill may exceed its fair value. The Company performs testing for impairment of goodwill in its third quarter, or as events occur or circumstances change that would more likely than not reduce the fair value of the Company’s reporting units below their carrying amounts. A qualitative assessment is first made to determine whether it is necessary to perform the two-step quantitative goodwill impairment test. This initial qualitative assessment includes, among other things, consideration of: (i) market capitalization of the Company, (ii) past, current and projected future earnings and equity; (iii) recent trends and market conditions; and (iv) valuation metrics involving similar companies that are publicly-traded and acquisitions of similar companies, if available. If this initial qualitative assessment indicates that it is more likely than not that impairment exists, a second analysis will be performed, involving a comparison between the estimated fair values of the Company’s reporting unit with its respective carrying amount including goodwill. If the carrying value exceeds estimated fair value, there is an indication of potential impairment, and a third analysis is performed to measure the amount of impairment. The third analysis involves calculating an implied fair value of goodwill by measuring the excess of the estimated fair value of the reporting unit over the aggregate estimated fair values of the individual assets less liabilities. If the carrying value of goodwill exceeds the implied fair value of goodwill, an impairment charge is recorded for the excess. Intangible assets with estimable useful lives are amortized over their respective estimated useful lives to their estimated residual values, and reviewed for impairment in accordance with ASC 360-10-35, “Accounting for Impairment or Disposal of Long-Lived Assets.” The Company evaluates for goodwill impairment annually at September 30 th and at the end of the third quarter of 2019 , and 2018 , the Company determined that it was not more-likely that the fair value of the reporting units is less than their carrying amount. Accordingly, the Company did not perform the two-step goodwill impairment test on both the Company's Business and Consumer segments. The Company assessed qualitative facts while summarizing the totality of events and circumstances and considered the extent to which adverse events or circumstances could affect the reporting unit's fair value as well as the consideration of positive and mitigating events and circumstances that would affect the determination of whether it was more likely than not that the fair value of a reporting unit is less than its carrying amount. Business Combinations Business combinations are accounted for using the acquisition method and accordingly, the assets acquired (including identified intangible assets), the liabilities assumed and any noncontrolling interest in the acquired business are recorded at their acquisition date fair values. The Company’s acquisition model typically provides for an initial payment at closing and for future additional contingent purchase price obligations. Contingent purchase price obligations are recorded as deferred acquisition consideration on the balance sheet at the acquisition date fair value and are remeasured at each reporting period. Changes in such estimated values are recorded in the results of operations. For further information, see Note 8 of the Notes to the Consolidated Financial Statements included herein. For each acquisition, the Company undertakes a detailed review to identify other intangible assets and a valuation is performed for all such identified assets. The Company uses several market participant measurements to determine estimated value. This approach includes consideration of similar and recent transactions, as well as utilizing discounted expected cash flow methodologies. A substantial portion of the intangible asset value that the Company acquires is the specialized know-how of the workforce, which is treated as part of goodwill and is not required to be valued separately. The majority of the value of the identifiable intangible assets acquired is derived from customer relationships, including the related customer contracts, as well as trade names. In executing the Company’s overall acquisition strategy, one of the primary drivers in identifying and executing a specific transaction is the existence of, or the ability to, expand the existing client relationships. The expected benefits of the Company’s acquisitions are typically shared across multiple agencies and regions. Impairment of Long-Lived Assets In accordance with ASC 360-10, “Accounting for the Impairment or Disposal of Long-lived Assets,” long-lived assets, such as property and equipment, and purchased intangibles subject to amortization are reviewed for impairment whenever events or changes in circumstances indicate that the carrying value of an asset may not be recoverable. The amount of any impairment is measured as the difference between the carrying value and the fair value of the impaired asset. Revenue Recognition The majority of the Company’s revenue is generated from monthly service revenues and related professional services from the sale of the LivePerson services. Revenues are recognized when control of these services is transferred to the Company's customers, in an amount that reflects the consideration the Company expects to be entitled to in exchange for those services. The Company determines revenue recognition through the following steps: • Identification of the contract, or contracts, with a customer; • Identification of the performance obligations in the contract; • Determination of the transaction price; • Allocation of the transaction price to the performance obligations in the contract; and • Recognition of revenue when, or as, the Company satisfies a performance obligation. Total revenue of $291.6 million , $249.8 million , and $218.9 million was recognized during the years ended December 31, 2019 , December 31, 2018 and December 31, 2017, respectively. The Company has made the following accounting policy election and elected to use a practical expedient specific to certain revenue streams, as permitted by the FASB, in applying Topic 606. The Company utilizes the right-to-invoice practical expedient with regard to the recognition of revenue upon the invoicing of certain revenue streams, as revenue for those streams are billed monthly. Under Topic 606, the Company defers all incremental commission costs ("contract acquisition costs") to obtain the contract. The contract acquisition costs, which are comprised of prepaid sales commissions, have balances at December 31, 2019 and 2018 of $32.0 million and $13.4 million , respectively. The Company amortizes these costs over the related period of benefit using the customer expected life that the Company determined to be three to five years which is consistent with the transfer to the customer of the services to which the asset relates. The Company classifies contract acquisition costs as long-term unless they have an original amortization period of one year or less. Hosted Services- Business Revenue Hosted Services Business revenue is reported at the amount that reflects the ultimate consideration expected to be received and primarily consist of fees that provide customers access to LiveEngage, the Company’s enterprise-class, cloud-based platform. The Company has determined such access represents a stand-ready service provided continually throughout the contract term. As such, control and satisfaction of this stand-ready performance obligation is deemed to occur over time. The Company recognizes this revenue over time on a ratable basis over the contract term, beginning on the date that access to the LiveEngage platform is made available to the customer. The passage of time is deemed to be the most faithful depiction of the transfer of control of the services as the customer simultaneously receives and consumes the benefit provided by the Company’s performance. Subscription contracts are generally one year or longer in length, billed, monthly, quarterly or annually in advance. There is no significant variable consideration related to these arrangements. Additionally, for certain of the Company’s larger customers, the Company may provide call center labor through an arrangement with one or more of several qualified vendors. For most of these customers, the Company passes the fee it incurs with the labor provider and its fee for the hosted services through to its customers in the form of a fixed fee for each order placed via the Company’s online engagement solutions. For these Pay for Performance (‘‘PFP’’) arrangements in accordance with ASC-606, ‘‘Principal Agent Considerations’’, the Company acts as a principal in a transaction if it controls the specified goods or services before they are transferred to the customer. Professional Services Revenues Professional services revenue primarily consists of fees for deployment and optimization services, as well as training delivered on an on-demand basis which is deemed to represent a distinct stand-ready performance obligation. Professional Services Revenues are reported at the amount that reflects the ultimate consideration the Company expects to receive in exchange for such services. Control for the majority of the Company’s Professional Services contracts passes over time to the customer and is recognized ratably over the contracted period, as the passage of time is deemed to be the most faithful depiction of the transfer of control. For certain deployment services, which are not deemed to represent a distinct performance obligation, revenue will be recognized in the same manner as the fee for access to the LiveEngage platform, and as such will be recognized on a straight-line basis over the contract term. For services billed on a fixed price basis, revenue is recognized over time based on the proportion performed using inputs as the measure of progress toward complete satisfaction of the performance obligation. Professional service contracts are generally one year or longer in length, billed, monthly, quarterly or annually in advance. There is no significant variable consideration related to these arrangements. Contracts with Multiple Performance Obligations Some of the Company’s contracts with customers contain multiple performance obligations. For these contracts, the Company accounts for individual performance obligations separately if they are distinct. The transaction price is allocated to the separate performance obligations on a relative standalone selling price basis. The Company determines the standalone selling prices based on its overall pricing objectives, taking into consideration market conditions and other factors, including the value of its contracts, the cloud applications sold, and the number and types of users within its contracts. Hosted Services- Consumer Revenue For revenue from the Company’s Consumer segment generated from online transactions between Experts and Users, revenue is recognized at an amount net of Expert fees in accordance with ASC 606, “Principal Agent Considerations,” due primarily to the fact that the Expert is the primary obligor. Additionally, the Company performs as an agent without any risk of loss for collection, and is not involved in selecting the Expert or establishing the Expert’s fee. The Company collects a fee from the consumer and retains a portion of the fee, and then remits the balance to the Expert. Revenue from these transactions is recognized at the point in time when the transaction is complete and no significant performance obligations remain. Deferred Revenues The Company records deferred revenues when cash payments are received or due in advance of its performance. The increase in the deferred revenue balance for the year ended December 31, 2019 is primarily driven by cash payments received or due in advance of satisfying its performance obligations, partially offset by $42.4 million of revenues recognized that were included in the deferred revenue balance as of December 31, 2018 . The following table presents deferred revenue by revenue source (amounts in thousands): December 31, 2019 2018 Hosted services – Business $ 82,892 $ 51,689 Hosted services – Consumer 687 543 Professional services – Business 5,172 2,783 Total deferred revenue - short term $ 88,751 $ 55,015 Hosted services – Business $ — $ 19 Professional services – Business 438 203 Total deferred revenue - long term $ 438 $ 222 Disaggregated Revenue The following table presents the Company's revenues disaggregated by revenue source (amounts in thousands): December 31, 2019 2018 2017 Revenue: Hosted services – Business $ 225,705 $ 197,474 $ 178,686 Hosted services – Consumer 24,480 19,553 17,450 Professional services 41,424 32,811 22,740 Total revenue $ 291,609 $ 249,838 $ 218,876 Revenue by Geographic Location The Company is domiciled in the United States and has international operations in the United Kingdom, Asia-Pacific, Latin America and Western Europe, particularly France and Germany. The following table presents the Company's revenues attributable to domestic and foreign operations for the years ended (amounts in thousands): December 31, 2019 2018 2017 United States $ 170,815 $ 146,702 $ 137,433 Other Americas (1) 11,462 7,315 6,987 Total Americas 182,277 154,017 144,420 EMEA (2) (4) 78,301 71,318 56,310 APAC (3) 31,031 24,503 18,146 Total revenue $ 291,609 $ 249,838 $ 218,876 (1) Canada, Latin America and South America (2) Europe, the Middle East and Africa (“EMEA”) (3) Asia-Pacific (“APAC”) (4) Includes revenue from the United Kingdom of $50.4 million , $46.5 million , and $38.9 million for the year ended December 31, 2019 , 2018 , and 2017 , respectively. and from the Netherlands of $10.0 million , $8.7 million , and $2.0 million for the year ended December 31, 2019 , 2018 , and 2017 , respectively. Information about Contract Balances Amounts collected in advance of services being provided are accounted for as deferred revenue. Nearly all of the Company's deferred revenue balance is related to Hosted Services- Business Revenue. In some arrangements, the Company allows customers to pay for access to LiveEngage over the term of the software license. The Company refers to these as subscription transactions. Amounts recognized as revenue in excess of amounts billed are recorded as unbilled receivables. Unbilled receivables, anticipated to be invoiced in the next twelve months, are included in accounts receivable on the consolidated balance sheet. The opening and closing balances of the Company's accounts receivable, unbilled receivables, and deferred revenues are as follows (amounts in thousands): Accounts Receivable Unbilled Receivable Contract Acquisition Costs noncurrent Deferred Revenue (current) Deferred Revenue (long term) Opening Balance as of December 31, 2018 $ 34,211 $ 11,812 $ 13,361 $ 55,015 $ 222 Increase (decrease), net 36,107 5,490 18,604 33,736 216 Ending Balance as of December 31, 2019 $ 70,318 $ 17,302 $ 31,965 $ 88,751 $ 438 As of December 31, 2019 , the Company expects to recognize the long term performance obligations in 2020. Advertising Costs The Company expenses the cost of advertising and promoting its services as incurred in the sales and marketing expense on the consolidated statement of operations. Such costs totaled approximately $28.6 million , $17.4 million , and $15.8 million for the years ended December 31, 2019 , 2018 and 2017 , respectively. Stock-based Compensation In accordance with ASC Topic 718 -10, ‘‘Stock Compensation’’, the Company measures stock based awards at fair value and recognizes compensation expense for all share-based payment awards made to its employees and directors, including employee stock options. The Company estimates the fair value of stock options granted using the Black-Scholes valuation model. This model requires the Company to make estimates and assumptions including, among other things, estimates regarding the length of time an employee will retain vested stock options before exercising them, the estimated volatility of its common stock price and the number of options that will be forfeited prior to vesting. The fair value is then recognized on a straight line basis over the requisite service period of the award, which is generally three to four years . Changes in these estimates and assumptions can materially affect the determination of the fair value of the stock-based compensation and consequently, the related amount recognized in the consolidated statement of operations. Deferred Rent The Company records rent expense on a straight-line basis over the term of the related lease. The difference between the rent expense recognized for financial reporting purposes and the actual payments made in accordance with the lease agreement is recognized as deferred rent liability included in other liabilities on the Company’s consolidated balance sheets. Income Taxes Income taxes are accounted for under the asset and liability method. Under this method, deferred tax assets and liabilities are recognized for the future tax consequences attributable to differences between the financial statement carrying amounts of existing assets and liabilities and their respective tax bases and operating loss and tax credit carryforwards. Deferred tax assets and liabilities are measured using enacted tax rates expected to apply to taxable income in the years in which those temporary differences are expected to be recovered or settled. The effect on deferred tax assets and liabilities of a change in tax rates is recognized in results of operations in the period that the tax change occurs. In evaluating our ability to recover our deferred tax assets in the jurisdiction from which they arise, we consider all available positive and negative evidence, including scheduled reversals of deferred tax liabilities, projected future taxable income, tax-planning strategies, and results of recent operations. We include interest accrued on the underpayment of income taxes in interest expense and penalties, if any, related to unrecognized tax benefits in general and administrative expenses. Valuation allowances are established, when necessary, to reduce deferred tax assets to the amount expected to be realized Comprehensive Loss In accordance with ASC 220, ‘‘Comprehensive Income’’, the Company reports by major components and as a single total, the change in its net assets during the period from non-owner sources. Comprehensive income (loss) consists of net income (loss), and accumulated other comprehensive income (loss), which includes certain changes in equity that are excluded from net income (loss). The Company’s comprehensive loss for all periods presented is related to the effect of foreign currency translation. Recently Issued Accounting Standards In June 2016, the Financial Accounting Standards Board (“FASB”) issued Accounting Standards Update (‘‘ASU’’) 2016‑13, “Financial Instruments-Credit Losses: Measurement of Credit Losses on Financial Instruments,” which changes the impairment model for most financial assets. The new model uses a forward‑looking expected loss method, which will generally result in earlier recognition of allowances for losses. In November 2018, the FASB issued ASU 2018‑19, “Codification Improvements to Topic 326, Financial Instruments- Credit Losses,” which clarifies that receivables arising from operating leases are not within the scope of Topic 326, Financial Instruments-Credit Losses. Instead, impairment of receivables arising from operating leases should be accounted for in accordance with Topic 842, Leases . In April 2019, the FASB issued ASU 2019-04, ‘‘Codification Improvements to Topic 326, Financial Instruments-Credit Losses, Topic 815, Derivatives and Hedging, and Topic 825, Financial Instruments,’’ which clarifies treatment of certain credit losses. In May 2019, the FASB issued ASU 2019-05, ‘‘Financial Instruments - Credit Losses (Topic 326): Targeted Transition Relief,’’ which permits an entity, upon adoption of ASU 2016-13, to irrevocably elect the fair value option (on an instrument-by instrument basis) for eligible financial assets measured at amortized cost basis. These ASUs are effective for annual and interim periods beginning after January 1, 2020, and early adoption is permitted. The Company does

Net Loss per Share

Net Loss per Share	12 Months Ended
	Dec. 31, 2019
Earnings Per Share [Abstract]
Net Loss per Share	Net Loss per Share The Company calculates earnings per share (“EPS”) in accordance with the provisions of ASC 260-10 and the guidance of SEC Staff Accounting Bulletin (“SAB”) No. 98. Under ASC 260-10, basic EPS excludes dilution for common stock equivalents and is computed by dividing net income or loss attributable to common shareholders by the weighted average number of common shares outstanding for the period. All options, warrants or other potentially dilutive instruments issued for nominal consideration are required to be included in the calculation of basic and diluted net income attributable to common stockholders. Diluted EPS is calculated using the treasury stock method and reflects the potential dilution that could occur if securities or other contracts to issue common stock were exercised or converted into common stock and resulted in the issuance of common stock. Diluted net loss per common share for the year ended December 31, 2019 does not include the effect of options to purchase 8,848,907 shares of common stock awards as the effect of their inclusion is anti-dilutive. Diluted net loss per common share for the year ended December 31, 2018 does not include the effect of options to purchase 8,957,672 shares of common stock awards as the effect of their inclusion is anti-dilutive. Diluted net loss per common share for the year ended December 31, 2017 does not include the effect of options to purchase 8,831,798 shares of common stock awards as the effect of their inclusion is anti-dilutive. A reconciliation of shares used in calculating basic and diluted earnings per share follows: Year Ended December 31, 2019 2018 2017 Basic 62,593,026 59,203,400 56,358,017 Effect of assumed exercised options — — — Diluted 62,593,026 59,203,400 56,358,017

Segment Information

Segment Information	12 Months Ended
	Dec. 31, 2019
Segment Reporting [Abstract]
Segment Information	Segment Information The Company accounts for its segment information in accordance with the provisions of ASC 280-10, “Segment Reporting.” ASC 280-10 establishes annual and interim reporting standards for operating segments of a company. ASC 280-10 requires disclosures of selected segment-related financial information about products, major customers, and geographic areas based on the Company’s internal accounting methods. The Company is organized into two operating segments for purposes of making operating decisions and assessing performance. The Business segment enables brands to leverage LiveEngage’s sophisticated intelligence engine to connect with consumers through an integrated suite of mobile and online business messaging technologies. The Consumer segment facilitates online transactions between independent service providers (“Experts”) and individual consumers (“Users”) seeking information and knowledge for a fee via mobile and online messaging. Both segments currently generate their revenue primarily in the United States. The chief operating decision maker, who is the chief executive officer, evaluates performance, makes operating decisions, and allocates resources based on the operating income of each segment. The reporting segments follow the same accounting polices used in the preparation of the Company’s consolidated financial statements which are described in the summary of significant accounting policies. The Company allocates cost of revenue, sales and marketing and amortization of purchased intangibles to the segments, but it does not allocate product development expenses, general and administrative expenses, restructuring costs and income tax expense because management does not use this information to measure performance of the operating segments. There are currently no inter-segment sales. Summarized financial information by segment for the year ended December 31, 2019 , based on the Company’s internal financial reporting system utilized by the Company’s chief operating decision maker, follows (amounts in thousands): Business Consumer Corporate Consolidated Revenue: Hosted services – Business $ 225,705 $ — $ — $ 225,705 Hosted services – Consumer — 24,480 — 24,480 Professional services – Business 41,424 — — 41,424 Total revenue 267,129 24,480 — 291,609 Cost of revenue 74,460 4,418 — 78,878 Sales and marketing 140,880 15,934 — 156,814 Amortization of purchased intangibles 1,794 — — 1,794 Unallocated corporate expenses — — 141,155 141,155 Operating income (loss) $ 49,995 $ 4,128 $ (141,155 ) $ (87,032 ) Summarized financial information by segment for the year ended December 31, 2018 , based on the Company’s internal financial reporting system utilized by the Company’s chief operating decision maker, follows (amounts in thousands): Business Consumer Corporate Consolidated Revenue: Hosted services – Business $ 197,474 $ — $ — $ 197,474 Hosted services – Consumer — 19,553 — 19,553 Professional services – Business 32,811 — — 32,811 Total revenue 230,285 19,553 — 249,838 Cost of revenue 58,420 4,059 — 62,479 Sales and marketing 94,339 9,005 — 103,344 Amortization of purchased intangibles 1,670 — — 1,670 Unallocated corporate expenses — — 106,048 106,048 Operating income (loss) $ 75,856 $ 6,489 $ (106,048 ) $ (23,703 ) Summarized financial information by segment for the year ended December 31, 2017 , based on the Company’s internal financial reporting system utilized by the Company’s chief operating decision maker, follows (amounts in thousands): Business Consumer Corporate Consolidated Revenue: Hosted services – Business $ 178,686 $ — $ — $ 178,686 Hosted services – Consumer — 17,450 — 17,450 Professional services – Business 22,740 — — 22,740 Total revenue 201,426 17,450 — 218,876 Cost of revenue 54,600 3,605 — 58,205 Sales and marketing 82,420 8,485 — 90,905 Amortization of purchased intangibles 1,840 — — 1,840 Unallocated corporate expenses — — 85,752 85,752 Operating income (loss) $ 62,566 $ 5,360 $ (85,752 ) $ (17,826 ) Geographic Information The Company is domiciled in the United States and has international operations in the United Kingdom, Asia-Pacific, Latin America and Western Europe, particularly France and Germany. The following table presents the Company's long-lived assets by geographic region for the periods presented (amounts in thousands): December 31, 2019 2018 United States $ 177,776 $ 128,647 Israel 16,680 14,140 Australia 13,765 9,529 Netherlands 7,705 7,452 Other (1) 18,677 8,611 Total long-lived assets $ 234,603 $ 168,379 (1) United Kingdom, Germany, Japan, France, Italy, Singapore, Canada, and Spain

Property and Equipment

Property and Equipment	12 Months Ended
	Dec. 31, 2019
Property, Plant and Equipment [Abstract]
Property and Equipment	Property and Equipment The following table presents the detail of property and equipment for the periods presented (amounts in thousands): December 31, 2019 2018 Computer equipment and software $ 92,493 $ 79,161 Furniture, equipment and building improvements 16,487 14,132 Internal-use software development costs 52,544 19,240 161,524 112,533 Less: accumulated depreciation and amortization (85,288 ) (68,798 ) Total $ 76,236 $ 43,735 In accordance with its policy, the Company reviews the estimated useful lives of its fixed assets on an ongoing basis. As of December 31, 2019 and 2018, there was approximately $25.3 million , and 7.8 million , respectively, of internal-use software development costs related to projects currently still in development, therefore, are not yet subject to amortization. Aggregate depreciation and amortization expense for property and equipment was $16.4 million , $14.2 million and $12.4 million for the years ended December 31, 2019 , 2018 , and 2017

Goodwill and Intangible Assets

Goodwill and Intangible Assets	12 Months Ended
	Dec. 31, 2019
Goodwill and Intangible Assets Disclosure [Abstract]
Goodwill and Intangible Assets	Goodwill and Intangible Assets Goodwill The changes in the carrying amount of goodwill for the year ended December 31, 2019 are as follows (amounts in thousands): Business Consumer Total Balance as of December 31, 2018 $ 87,007 $ 8,024 $ 95,031 Adjustments to goodwill: Foreign exchange adjustments (44 ) — (44 ) Balance as of December 31, 2019 $ 86,963 $ 8,024 $ 94,987 The changes in the carrying amount of goodwill for the year ended December 31, 2018 are as follows (amounts in thousands): Business Consumer Total Balance as of December 31, 2017 $ 72,507 $ 8,024 $ 80,531 Adjustments to goodwill: Acquisitions 14,606 — 14,606 Foreign exchange adjustments (106 ) — (106 ) Balance as of December 31, 2018 $ 87,007 $ 8,024 $ 95,031 The total accumulated goodwill impairment charges are $23.5 million through December 31, 2019 . No impairment was recognized for the years ended December 31, 2019 , 2018 , and 2017 . Intangible Assets Intangible assets are summarized as follows (see Note 8) (amounts in thousands): December 31, 2019 Gross Carrying Amount Accumulated Amortization Net Carrying Amount Weighted Average Amortization Period Amortizing intangible assets: Technology $ 30,413 $ (25,187 ) $ 5,226 5.3 years Customer relationships 16,964 (12,958 ) 4,006 8.4 years Patents 3,267 (714 ) 2,553 12.8 years Other 262 (235 ) 27 2.7 years Total $ 50,906 $ (39,094 ) $ 11,812 December 31, 2018 Gross Carrying Amount Accumulated Amortization Net Carrying Amount Weighted Average Amortization Period Amortizing intangible assets: Technology $ 30,447 $ (23,615 ) $ 6,832 5.3 years Customer relationships 17,219 (11,786 ) 5,433 8.4 years Patents 2,074 (534 ) 1,540 12.4 years Other 262 (235 ) 27 2.7 years Total $ 50,002 $ (36,170 ) $ 13,832 Amortization expense is calculated over the estimated useful life of the asset. Aggregate amortization expense for intangible assets was $2.9 million , $2.8 million and $4.7 million for the years ended December 31, 2019 , 2018 and 2017 , respectively. For the years ended December 31, 2019 , 2018 and 2017 , a portion of this amortization is included in cost of revenue. Estimated amortization expense for the next five years are as follows (amounts in thousands): Estimated Amortization Expense 2020 $ 2,734 2021 2,520 2022 2,155 2023 904 2024 705 Thereafter 2,794 Total $ 11,812

Accrued Liabilities and Other C

Accrued Liabilities and Other Current Liabilities	12 Months Ended
	Dec. 31, 2019
Payables and Accruals [Abstract]
Accrued Liabilities and Other Current Liabilities	Accrued Liabilities and Other Current Liabilities The following table presents the detail of accrued liabilities and other current liabilities for the periods presented (amounts in thousands): December 31, 2019 2018 Payroll and other employee related costs $ 27,920 $ 19,014 Professional services, consulting and other vendor fees 20,382 17,461 Unrecognized tax benefits 2,053 1,913 Sales commissions 9,654 6,239 Contingent earn-out (Note 8) 557 2,372 Restructuring 314 977 Other 1,898 2,686 Total $ 62,778 $ 50,662

Convertible Senior Notes and Ca

Convertible Senior Notes and Capped Call Transactions	12 Months Ended
	Dec. 31, 2019
Debt Disclosure [Abstract]
Convertible Senior Notes and Capped Call Transactions	Convertible Senior Notes and Capped Call Transactions In March 2019, the Company issued $230.0 million aggregate principal amount of 0.750% Convertible Senior Notes due 2024 in a private placement, which amount includes $30.0 million aggregate principal amount of such Notes pursuant to the exercise in full of the over-allotment options of the initial purchasers (collectively, the “Notes”). The interest on the Notes is payable semi-annually in arrears on March 1 and September 1 of each year, beginning on September 1, 2019. The Notes will mature on March 1, 2024, unless earlier repurchased or redeemed by the Company or converted pursuant to their terms. The total net proceeds from the debt offering, after deducting debt issuance costs, paid or payable by us, was approximately $221.4 million . Each $1,000 principal amount of the Notes is initially convertible into 25.9182 shares of the Company’s common stock par value $0.001 , which is equivalent to an initial conversion price of approximately $38.58 per share. The conversion rate is subject to adjustment upon the occurrence of certain specified events but will not be adjusted for any accrued and unpaid interest. In addition, following certain corporate events that occur prior to the maturity date, the Company will increase the conversion rate for a holder who elects to convert its Notes in connection with such a corporate event. The Notes are not redeemable prior to the maturity date of the Notes and no sinking fund is provided for the Notes. If we undergo a fundamental change (as defined in the indenture governing the Notes) prior to the maturity date, holders may require us to repurchase for cash all or any portion of their Notes in principal amounts of $1,000 or a multiple thereof at a fundamental change repurchase price equal to 100% of the principal amount of the Notes to be repurchased, plus accrued and unpaid interest to, but excluding, the fundamental change repurchase date. Holders of the Notes may convert their Notes at their option at any time prior to the close of business on the business day immediately preceding November 1, 2023, in multiples of $1,000 principal amount, only under the following circumstances: (1) during any calendar quarter commencing after the calendar quarter ending on June 30, 2019 (and only during such calendar quarter), if the last reported sale price of the Company’s 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 for the Notes on each applicable trading day as determined by the Company; (2) during the five business day period after any five consecutive trading day period (the “measurement period”) in which the “trading price” (as defined in the indenture governing the Notes) per $1,000 principal amount of Notes for each trading day of the measurement period was less than 98% of the product of the last reported sale price of the Company’s common stock and the conversion rate for the Notes on each such trading day; or (3) upon the occurrence of specified corporate events. On or after November 1, 2023, holders may convert all or any portion of their Notes at any time prior to the close of business on the second scheduled trading day immediately preceding the maturity date, regardless of the foregoing circumstances. Upon conversion, the Company will pay or deliver, as the case may be, cash, shares of its common stock or a combination of cash and shares of its common stock, at the Company’s election. It is the Company’s current intent to settle the principal amount of its outstanding Notes in cash and any excess in shares of the Company’s common stock. As of December 31 2019, the conditions allowing holders of the Notes to convert were not met. The Notes are senior unsecured obligations and will rank senior in right of payment to any of the Company’s indebtedness that is expressly subordinated in right of payment to the Notes; equal in right of payment with the Company’s existing and future liabilities that are not so subordinated; effectively subordinated to any of the Company’s secured indebtedness to the extent of the value of the assets securing such indebtedness; and structurally junior to all indebtedness and other liabilities (including trade payables) of current or future subsidiaries of the Company. In accounting for the issuance of the Notes, the Company separated the Notes into liability and equity components. The carrying amount of the liability component was calculated by measuring the fair value of a similar debt instrument that does not have an associated convertible feature. The carrying amount of the equity component representing the conversion option was $52.9 million and was determined by deducting the fair value of the liability component from the par value of the Notes. The equity component is not remeasured as long as it continues to meet the conditions for equity classification. The excess of the principal amount of the liability component over its carrying amount, or the debt discount, is amortized to interest expense at an effective interest rate over the contractual terms of the Notes. In accounting for the transaction costs related to the Notes, the Company allocated the total amount incurred of approximately $8.6 million to the liability and equity components of the Notes based on the proportion of the proceeds allocated to the debt and equity components. Issuance costs attributable to the liability component were approximately $6.6 million , were recorded as an additional debt discount and are amortized to interest expense using the effective interest method over the contractual terms of the Notes. Issuance costs attributable to the equity component were approximately $2.0 million and recorded as a reduction of additional paid in capital in stockholders’ equity. The net carrying amount of the liability component of the Notes was as follows (in thousands): As of December 31, 2019 Principal $ 230,000 Unamortized discount (45,295 ) Unamortized issuance costs (5,693 ) Net carrying amount $ 179,012 The net carrying amount of the equity component of the Notes was as follows (in thousands): As of December 31, 2019 Proceeds allocated to the conversion options (debt discount) $ 52,900 Issuance costs (1,986 ) Net carrying amount $ 50,914 The following table sets forth the interest expense recognized related to the Notes (in thousands): For the Year Ended December 31, 2019 Contractual interest expense $ 1,438 Amortization of issuance costs 956 Amortization of debt discount 7,605 Total interest expense $ 9,999 The remaining term over which the debt discount and debt issuance costs will be amortized is 4.2 years . The effective interest rate on the debt was 5.88% for the year ended December 31 2019. Interest expense of $10.0 million is reflected as a component of interest (expense) income, net in the accompanying consolidated statement of operations for the year ended December 31, 2019. In connection with the offering of the Notes, the Company entered into privately-negotiated capped call option transactions with certain counterparties (the “capped calls”). The capped calls each have an initial strike price of approximately $38.58 per share, subject to certain adjustments, which corresponds to the initial conversion price of the Notes. The capped calls have initial cap prices of $57.16 per share, subject to certain adjustment events. The capped calls cover, subject to anti-dilution adjustments, approximately 5.96 million shares of common stock. The capped calls are generally intended to reduce or offset the potential dilution to the common stock upon any conversion of the Notes with such reduction or offset, as the case may be, subject to a cap based on the cap price. The capped calls expire on March 1, 2024, subject to earlier exercise. The capped calls are subject to either adjustment or termination upon the occurrence of specified extraordinary events affecting the Company, including a merger event, a tender offer, and a nationalization, insolvency or delisting involving the Company. In addition, the capped calls are subject to certain specified additional disruption events that may give rise to a termination of the capped calls, including changes in law, failure to deliver, and hedging disruptions. The capped calls are recorded in stockholders’ equity and are not accounted for as derivatives. The net cost of $23.2 million incurred to purchase the capped calls was recorded as a reduction to additional paid-in capital in the accompanying consolidated balance sheet.

Acquisitions

Acquisitions	12 Months Ended
	Dec. 31, 2019
Business Combinations [Abstract]
Acquisitions	Acquisitions AdvantageTec Inc. In October 2018, the Company entered into a stock purchase agreement to acquire the outstanding equity interest of AdvantageTec Inc. (“AdvantageTec”), a leading provider of texting solutions for service departments of automotive dealerships that helps enable the conversational experience across the entire dealership, including both front end/variable operations (new and used vehicle sales) and back end/fixed operations (parts and services). The purchase agreement was for total consideration of approximately $11.2 million , which includes approximately $6.0 million in cash, approximately $4.3 million in shares of common stock, and approximately $0.9 million of potential earn-out consideration in cash and shares of common stock. The earn-out is contingent upon achieving certain targeted financial, strategic and integration objectives and milestones and is included as part of the purchase price. During the year, the Company assessed this earn-out and recorded a $0.2 million fair value re-measurement adjustment, which was recorded in loss from operations as an increase in general and administrative expenses. In 2019, the Company made $0.5 million of payments in earn-out consideration, with potential future earn-out payments of $0.4 million . The purchase price allocation resulted in approximately $9.1 million of goodwill and approximately $2.2 million of intangible assets. The goodwill will not be deductible for tax purposes. The intangible assets are being amortized over their expected period of benefit. A deferred tax liability for the identified intangibles has been recorded. AdvantageTec Inc. enhances the Company’s messaging platform available for the automotive industry and is included in the Company's business segment. Conversable, Inc. In September 2018, the Company acquired the employees and technology assets of Conversable, Inc. a SaaS based Artificial Intelligence powered conversational platform, headquartered in Austin, Texas, for an aggregate estimated purchase price of $5.7 million . The estimated purchase price consisted of $1.3 million in cash, approximately $2.9 million in shares of common stock of the Company, and a potential earn-out consideration of $1.5 million in cash, which is based on achieving certain targeted financial, strategic, and integration objectives and milestones and is included as part of the purchase price. In 2019 the Company assessed this earn-out and recorded a $0.5 million fair value re-measurement adjustment, which was recorded in loss from operations as a decrease in general and administrative expenses. This transaction was accounted for under the purchase method of accounting and was based upon the estimated fair value of Conversable, Inc.'s net tangible and identifiable intangible assets as of the date of acquisition. The purchase price allocation resulted in approximately $5.5 million of goodwill and approximately $0.5 million of intangible assets. The goodwill will be deductible for tax purposes. The intangible assets are being amortized over their expected period of benefit. The allocation of the purchase price to net book value of acquired assets and liabilities resulted in a net liability $0.3 million , which includes accounts receivable, property and equipment, accrued expenses, and deferred revenue. Conversable Inc.’s capabilities will accelerate the ongoing expansion of the Company’s Conversational Space solutions and enhance the Company’s ability to deliver proactive and personalized content and services when and where the customer needs it, helping consumers find immediate service through messaging. Conversable, Inc. will be included in the Company’s business segment. The results of this acquisition were not significant to the results of operations for the year ended December 31, 2018. BotCentral, Inc. In January 2018, the Company acquired the employees and technology assets of BotCentral, Inc., a Silicon Valley based startup, for an approximate purchase price of $1.0 million in common stock of the Company. The Company incurred an additional $0.2 million related to acquisition costs. This transaction was accounted for as an asset purchase. The aggregate amount of approximately $0.2 million is included in intangibles on the Company’s consolidated balance sheet. With the team’s expertise and knowledge of LiveEngage platform, the team is bringing valuable insight for the Company’s customers and partners, and enabling the Company to more rapidly optimize its bot deployment capabilities, and grow the ecosystem. BotCentral, Inc. will be included in the Company’s business segment. The results of this acquisition were not significant to the results of operations for the year ended December 31, 2018.

Fair Value Measurements

Fair Value Measurements	12 Months Ended
	Dec. 31, 2019
Fair Value Disclosures [Abstract]
Fair Value Measurements	Fair Value Measurements The Company measures its cash equivalents at fair value based on an expected exit price as defined by the authoritative guidance on fair value measurements, which represents the amount that would be received on the sale of an asset or paid to transfer a liability, as the case may be, in an orderly transaction between market participants. As such, fair value may be based on assumptions that market participants would use in pricing an asset or liability. The authoritative guidance on fair value measurements establishes a consistent framework for measuring fair value on either a recurring or nonrecurring basis whereby inputs, used in valuation techniques, are assigned a hierarchical level. The following are the hierarchical levels of inputs to measure fair value: • Level 1: Observable inputs that reflect quoted prices (unadjusted) for identical assets or liabilities in active markets. • Level 2: Inputs reflect: quoted prices for identical assets or liabilities in markets that are not active; quoted prices for similar assets or liabilities in active markets; inputs other than quoted prices that are observable for the assets or liabilities; or inputs that are derived principally from or corroborated by observable market data by correlation or other means. • Level 3: Unobservable inputs reflecting the Company’s assumptions incorporated in valuation techniques used to determine fair value. These assumptions are required to be consistent with market participant assumptions that are reasonably available. Financial Assets and Liabilities The carrying amount of cash, accounts receivable, and accounts payable approximate their fair value due to their short-term nature. The Company's assets and liabilities that are measured at fair value on a recurring basis, by level, within the fair value hierarchy as of December 31, 2019 and December 31, 2018 , are summarized as follows (amounts in thousands). December 31, 2019 December 31, 2018 Level 1 Level 2 Level 3 Total Level 1 Level 2 Level 3 Total Assets: Cash equivalents: Money market funds $ 2,899 $ — $ — $ 2,899 $ 2,828 $ — $ — $ 2,828 Total assets $ 2,899 $ — $ — $ 2,899 $ 2,828 $ — $ — $ 2,828 Liabilities: Contingent earn-out $ — $ — $ 557 $ 557 $ — $ — $ 2,372 $ 2,372 Total liabilities $ — $ — $ 557 $ 557 $ — $ — $ 2,372 $ 2,372 In determining fair value, the Company utilizes valuation techniques that maximize the use of observable inputs and minimize the use of unobservable inputs to the extent possible as well as considers counterparty credit risk in its assessment of fair value. Observable or market inputs reflect market data obtained from independent sources, while unobservable inputs reflect the Company’s assumptions based on the best information available. The Company’s money market funds are measured at fair value on a recurring basis based on quoted market prices in active markets and are classified as level 1 within the fair value hierarchy. The Company’s contingent earn-out liability is measured at fair value on a recurring basis and is classified as level 3 within the fair value hierarchy. On a nonrecurring basis, the Company uses fair value measures when analyzing asset impairment. Long-lived tangible assets are reviewed for impairment whenever events or changes in circumstances indicate that the carrying amount of an asset may not be recoverable. If it is determined such indicators are present and the review indicates that the assets will not be fully recoverable, based on undiscounted estimated cash flows over the remaining amortization periods, their carrying values are reduced to estimated fair value. The Company uses an income approach and inputs that constitute level 3. During the third quarter of each year, the Company evaluates goodwill for impairment at the reporting unit level. The Company uses qualitative factors in accordance with ASU No. 2011-08 to determine whether it is ‘‘more likely than not’’ that the fair value of a reporting unit is less than its carrying amount as a basis for determining whether it is necessary to perform the two-step goodwill impairment test. This measurement is classified based on level 3 input. As of December 31, 2019 the fair value of the Notes, as further described in Note 7 above, was approximately $194.3 million . Management determines the fair value by utilizing an independent valuation specialist using the antithetic variable technique and is considered a Level 2 fair value measurement. The Company recorded a contingent earn-out of $2.4 million in December 2018 in connection with the acquisitions of Conversable, Inc. and AdvantageTec Inc. The contingent earn-out is based on achieving certain targeted financial, strategic, and integration objectives. The unobservable inputs considered are probability factors and the time value of money. During the year ended December 31, 2019, the contingent earn-out decreased by $1.8 million due to a decrease in re-measurement to fair value of Conversable, Inc. of $0.5 million and payments of $0.5 million in cash and $1.0 million in shares, offset in part by an increase of re-measurement to fair value of Advantage, Inc. of $0.2 million . The changes in fair value of the Level 3 liabilities are as follows (amounts in thousands): Contingent Earn-Out December 31, 2019 2018 Balance, Beginning of year $ 2,372 $ — Conversable, Inc. fair value adjustment (see Note 7) (496 ) 1,496 AdvantageTec, Inc. fair value adjustment (see Note 7) 168 876 Payments (1,487 ) — Balance, End of year $ 557 $ 2,372 Derivative Financial Instruments The Company is exposed to foreign exchange risks that in part are managed by using derivative financial instruments. The Company entered into foreign currency forward contracts related to risks associated with foreign operations. The Company does not use derivatives for trading purposes. Derivatives are recorded at their estimated fair values based upon Level 2 inputs. Derivatives designated and effective as cash flow hedges are reported as a component of other comprehensive income and reclassified to earnings in the same periods in which the hedged transactions impact earnings. Gains and losses related to derivatives not meeting the requirements of hedge accounting and the portion of derivatives related to hedge ineffectiveness are recognized in current earnings. As of December 31 2019 and 2018, the Company is not party to any foreign currency forward contracts and does not have any restricted cash balance. The following summarizes certain information regarding the Company’s derivatives that are not designated or are not effective as hedges (in thousands): Gain (losses) on Derivative Instruments Recognized in the Statement of Operations Statement of Operations Location December 31, 2019 December 31, 2018 December 31, 2017 Foreign currency derivatives contracts Other Income (Expense), net $ — $ (50 ) $ 236

Commitments and Contingencies

Commitments and Contingencies	12 Months Ended
	Dec. 31, 2019
Commitments and Contingencies Disclosure [Abstract]
Commitments and Contingencies	Commitments and Contingencies Contractual Obligations The Company leases facilities and certain car leases (the ‘‘leases’’) under agreements accounted for as operating leases. The leases have initial lease terms ranging from 1 to 12 years . Payments due under the lease contracts include primarily fixed payments. The lease terms include periods under options to extend or terminate the lease when it is reasonably certain that we will exercise that option. Currently, there are no operating leases where we believe it is reasonably certain that the Company will exercise any option to extend the initial term. The Company has evaluated its facility leases and determined which leases met the definition of the new standard in accordance with Topic 842. The Company also performed an evaluation of their other contracts with suppliers in accordance with Topic 842 and have determined that, except for the facilities and car leases described above, none of its supply contracts contain a lease. Further, the Company has made an accounting policy election to keep leases with a term of twelve months or less off the balance sheet. This policy applies to all classes of the underlying assets. The Company will recognize those lease payments and associated interest expense in the consolidated statement of operations evenly over the lease term. The Company elected the “package of practical expedients,” which permits the Company not to reassess under ASC 842 its prior conclusions about lease identification, lease classification and initial direct costs. The Company also made a policy election not to separate non-lease components from lease components. Furthermore, the Company elected to not capitalize leases with a term of 12 months or less and recognize the lease expense for such leases generally on a straight-line basis over the lease term. In connection with the leases, the Company recognized operating lease right-of-use assets of $15.7 million and an aggregate lease liability of $19.5 million in its consolidated balance sheet as of December 31, 2019 . The determination of the discount rate used to calculate the present value of the right-of-use assets and lease liabilities depends on whether an interest rate is specified in the lease or not. If the lease specifies a rate, that rate is used when calculating the present value of lease payments. If the rate is not readily determinable, which is generally the case for the Company, the Company’s incremental borrowing rate (“IBR”) as of the date of inception of the lease is used (for initial measurement, the IBR was determined as of the adoption date of the standard). The IBR is the rate of interest that the Company would have to pay to borrow on a collateralized basis over a similar term and amount equal to the lease payments in a similar economic environment. The Company used a ratings benchmark report against its peers in the technology sector. The Company has operating leases for its corporate offices and other service agreements. The Company's leases have remaining lease terms of 1 to 12 years , some of which include options to extend. The Company's lease expense for the year ended December 31, 2019 consisted entirely of operating leases was approximately $13.0 million . Operating lease payments, which reduced operating cash flows for the year ended December 31, 2019 was approximately $7.0 million . Supplemental balance sheet information related to leases was as follows: As of December 31, 2019 Operating Leases (in thousands, except lease term and discount rate) Right-of-use asset, net $ 15,680 Current operating lease liability 6,602 Long term operating lease liability 12,865 Total operating lease liability $ 19,467 Weighted Average Remaining Lease Term Operating leases 3.5 years Weighted Average Discount Rate Operating leases 7 % Future minimum lease payments under non-cancellable operating leases (with an initial or remaining lease terms in excess of one year) are as follows (amounts in thousands): Year Ending December 31, Operating Leases 2020 $ 7,787 2021 6,530 2022 3,746 2023 1,925 2024 1,148 Thereafter 864 Total minimum lease payments $ 22,000 Less: present value adjustment (2,533 ) Total operating lease liability $ 19,467 Rental expense for operating leases and other service agreements was approximately $13.0 million , $10.9 million and $9.9 million for the years ended December 31, 2019, 2018 and 2017 respectively. Employee Benefit Plans The Company has a 401(k) defined contribution plan covering all eligible employees. In 2018, the Company provided for employer matching contributions equal to 50% of employee contributions, up to the lesser of 5% of eligible compensation or $6,000 . Matching contributions are deposited into the employee’s 401(k) account and are subject to 5 year graded vesting. Beginning in 2019, the Company’s 401(k) policy was changed to a Safe Harbor Plan, whereby the Company matches 100% of the first 3% of eligible compensation and 50% of the next 2% of eligible compensation. Furthermore, the match is immediately vested. Total Company matching contributions were $3.2 million , $1.6 million , and $1.4 million for the years ended December 31, 2019 , 2018 and 2017 , respectively. Indemnifications The Company enters into service and license agreements in its ordinary course of business. Pursuant to some of these agreements, the Company agrees to indemnify certain customers from and against certain types of claims and losses suffered or incurred by them as a result of using the Company’s products. The Company also has agreements whereby its executive officers and directors are indemnified for certain events or occurrences while the officer or director is, or was serving, at the Company’s request in such capacity. The maximum potential amount of future payments the Company could be required to make under these indemnification agreements is unlimited; however, the Company has a directors and officers insurance policy that reduces its exposure and enables the Company to recover a portion of any future amounts paid. As a result of its insurance policy coverage, the Company believes the estimated fair value of these indemnification agreements is minimal. The Company has no liabilities recorded for these agreements as of December 31, 2019 and 2018. Non-Income Related Taxes The Company is in the process of finalizing its sales tax liability analysis for states that it has economic nexus in. Although it is probable that the Company will be subject to sales tax liabilities plus interest in these states, the amount is not estimable at December 31, 2019. The Company expects to finalize its analysis by March 31, 2020.

Stockholders' Equity

Stockholders' Equity	12 Months Ended
	Dec. 31, 2019
Equity [Abstract]
Stockholders' Equity	Stockholders’ Equity Common Stock In November 2019, the Company filed an amendment to its Certificate of Incorporation to authorize an additional 100,000,000 shares of common stock. As December 31, 2019 , there were 200,000,000 shares of common stock authorized, and 66,543,073 and 63,833,243 shares issued and outstanding, respectively. As of December 31, 2018 , there were 100,000,000 shares of common stock authorized, and 63,676,229 and 60,994,944 shares issued and outstanding, respectively. The par value for common shares is $0.001 . Preferred Stock As of December 31, 2019 and 2018 , there were 5,000,000 shares of preferred stock authorized, and zero shares issued and outstanding. The par value for preferred shares is $0.001 . Stock Repurchase Program From 2012 through 2018, the Company had a stock repurchase program in place pursuant to which the Company was authorized to repurchase shares of its common stock, in the open market or privately negotiated transactions, at times and prices considered appropriate by the Board of Directors depending upon prevailing market conditions and other corporate considerations. The timing and actual number of shares repurchased depend on a variety of factors including the timing of open trading windows, price, corporate and regulatory requirements and other market conditions. The program was discontinued at the end of 2018. The Company may or may not enter into a new stock repurchase program in the future. Stock-Based Compensation The Company follows FASB ASC 718-10, “Stock Compensation,” which addresses the accounting for transactions in which an entity exchanges its equity instruments for goods or services, with a primary focus on transactions in which an entity obtains employee services in share-based payment transactions. ASC 718-10 requires measurement of the cost of employee services received in exchange for an award of equity instruments based on the grant-date fair value of the award. Incremental compensation costs arising from subsequent modifications of awards after the grant date must be recognized. The per share weighted average fair value of stock options granted during the years ended December 31, 2019 , 2018 and 2017 was $12.12 , $6.60 , and $4.25 , respectively. The fair value of each option grant is estimated on the date of grant using the Black-Scholes option-pricing model with the following weighted average assumptions for the years ended December 31, 2019 , 2018 and 2017 : December 31, 2019 2018 2017 Dividend yield —% —% —% Risk-free interest rate 1.66% – 3.05% 2.5% – 3.1% 1.7% – 2.1% Expected life (in years) 5.0 5.0 5.0 Historical volatility 43.42% – 44% 43.5% – 48.4% 46.6% – 48.1% A description of the methods used in the significant assumptions used to estimate the fair value of stock-based-based compensation awards follows: Dividend yield – The Company uses 0% as it has never issued dividends and does not anticipate issuing dividends in the near term. Risk-free interest rate – The Company uses the market yield on U.S. Treasury securities at five years with constant maturity, representing the current expected life of stock options in years. Expected life – The Company uses historical data to estimate the expected life of a stock option. Historical volatility – The Company uses a trailing five year from grant date to determine volatility. Stock Option Plans During 1998, the Company established the Stock Option and Restricted Stock Purchase Plan (the “1998 Plan”). Under the 1998 Plan, the Board of Directors could issue incentive stock options or nonqualified stock options to purchase up to 5,850,000 shares of common stock. The 2000 Stock Incentive Plan (the “2000 Plan”) succeeded the 1998 Plan. Under the 2000 Plan, the options which had been outstanding under the 1998 Plan were incorporated in the 2000 Plan increasing the number of shares available for issuance under the plan by approximately 4,150,000 , thereby reserving for issuance 10,000,000 shares of common stock in the aggregate. The Company established the 2009 Stock Incentive Plan (the “2009 Plan”) as a successor to the 2000 Plan. Under the 2009 Plan, the options which had been outstanding under the 2000 Plan were incorporated into the 2009 Plan and the Company increased the number of shares available for issuance under the plan by 6,000,000 . The Company amended the 2009 Plan (the “Amended 2009 Plan”) effective June 7, 2012. The Amended 2009 Plan increased the number of shares authorized for issuance under the plan by an additional 4,250,000 . On June 2, 2017, the Company's Board of Directors amended and restated the Amended 2009 Plan effective April 30, 2017. The amended and restated plan increased the number of shares authorized for issuance under the plan by an additional 4,000,000 . On April 11, 2019, the Company’s Board of Directors adopted, and on June 6, 2019, the Company’s stockholders approved, the 2019 Stock Incentive Plan (‘‘2019 Stock Incentive Plan’’) to replace the Amended 2009 Plan, which was set to expire under its terms on June 9, 2019. Under the 2019 Stock Incentive Plan, the number of shares underlying options and other equity awards which remain outstanding, as well as the number of shares that remained available for grant, under the Amended 2009 Plan and under the Amended 2000 Plan were incorporated, as of June 6, 2019, into the 2019 Stock Incentive Plan. In addition, under the 2019 Stock Incentive Plan, 4,250,000 new shares were authorized for issuance. The number of shares authorized for issuance under the 2019 Stock Incentive Plan, the Amended 2009 Plan, and the 2000 Plan is 32,067,744 shares in the aggregate. Options to acquire common stock granted thereunder have 10 -year terms. As of December 31, 2019, approximately 4.1 million shares of common stock remained available for issuance under the 2019 Stock Incentive Plan (taking into account all option exercises and other equity award settlements through December 31, 2019). Employee Stock Purchase Plan In June 2010, the Company’s stockholders approved the 2010 Employee Stock Purchase Plan with 1,000,000 shares of common stock initially reserved for issuance. Subject to stockholder approval, which was obtained on June 2, 2017, the Company's Board of Directors amended and restated the 2010 Employee Stock Purchase Plan effective April 30, 2017. The amended and restated plan increased the number of shares authorized for issuance under the plan by an additional 1,000,000 , thereby reserving for issuance 2,000,000 shares of common stock in the aggregate. On April 11, 2019, the Company’s Board of Directors adopted, and on June 6, 2019, the Company’s stockholders approved, the 2019 Employee Stock Purchase Plan (the ‘‘2019 Employee Stock Purchase Plan’’) to replace the Amended and Restated 2010 Employee Stock Purchase Plan which was set to expire under its terms in June 2020. There are 1,000,000 shares authorized and reserved for issuance under the 2019 Employee Stock Purchase Plan. As of December 31, 2019, approximately 0.9 million shares of common stock remain available for issuance under the 2019 Employee Stock Purchase Plan (taking into account all share purchases through December 31 2019). Inducement Plan During January 2018, the Company established the Inducement Plan (the “2018 Plan”). Under the 2018 Plan, the Board of Directors can issue nonqualified stock options or other equity-based awards in respect of up to 1,500,000 shares of common stock. On April 25, 2018, the Company’s Board of Directors amended and restated the 2018 Plan (the ‘‘Amended 2018 Plan’’). The Amended 2018 Plan increased the number of shares authorized for issuance under the plan by an additional 500,000 shares, and subsequently the Board of Directors has approved and ratified, effective as of July 31, 2018, October 29, 2018 and February 13, 2019, increases of the number of shares authorized for issuance under the Amended 2018 Plan by 500,000 , 250,000 and 618,048 shares, respectively, constituting 3,368,048 shares of common stock in the aggregate being reserved for issuance pursuant to grants under the Amended 2018 Plan. As of December 31, 2019, approximately 0.8 million shares of common stock remained available for issuance under the Amended 2018 Plan (taking into account all option exercises and other equity award settlements through December 31 2019). Stock Option Activity A summary of the Company’s stock option activity and weighted average exercise prices follows: Stock Option Activity Weighted Average Remaining Contractual Term (in years) Aggregate Intrinsic Value (in thousands) Options (in thousands) Weighted Balance outstanding at December 31, 2016 7,769 $ 10.88 Granted 2,042 9.87 Exercised (854 ) 8.80 Cancelled or expired (998 ) 11.98 Balance outstanding at December 31, 2017 7,959 $ 10.71 5.85 $ 14,881 Options vested and expected to vest 7,163 $ 10.75 5.49 $ 13,197 Options exercisable at December 31, 2017 5,163 $ 11.17 4.50 $ 8,648 Balance outstanding at December 31, 2017 7,959 $ 10.71 Granted 2,033 15.00 Exercised (3,120 ) 10.70 Cancelled or expired (606 ) 10.03 Balance outstanding at December 31, 2018 6,266 $ 12.13 6.55 $ 43,348 Options vested and expected to vest 5,550 $ 11.89 6.28 $ 39,521 Options exercisable at December 31, 2018 3,278 $ 11.12 4.64 $ 25,367 Balance outstanding at December 31, 2018 6,266 $ 12.13 Granted 1,425 29.76 Exercised (1,523 ) 11.12 Cancelled or expired (369 ) 14.76 Balance outstanding at December 31, 2019 5,799 $ 16.57 6.79 $ 119,064 Options vested and expected to vest 5,096 $ 15.29 6.49 $ 110,934 Options exercisable at December 31, 2019 2,901 $ 12.03 4.95 $ 72,424 The total fair value of stock options exercised during the years ended December 31, 2019 and 2018 was approximately $8.0 million and $16.1 million , respectively. As of December 31, 2019 , there was approximately $22.7 million of total unrecognized compensation cost related to nonvested share-based compensation arrangements. That cost is expected to be recognized over a weighted average period of approximately 2.4 years. The following table summarizes information about outstanding and vested stock options as of December 31, 2019 : Options Outstanding Options Exercisable Range of Exercise Prices Number of Shares Outstanding (in thousands) Weighted-Average Remaining Contractual Life (Years) Weighted-Average Exercise Price Number of Shares (in thousands) Weighted-Average Exercise Price $6.23 - $7.6 643 6.37 $ 7.42 392 $ 7.40 $7.95 - $10.05 648 4.83 9.47 604 9.48 $10.13 - $11.95 621 5.93 10.85 476 10.53 $11.96 - $12.32 50 1.51 12.10 50 12.10 $12.45 - $12.45 782 7.91 12.45 287 12.45 $12.46 - $14.3 758 3.62 13.57 628 13.41 $14.5 - $17.88 580 6.44 16.11 271 16.60 $18.09 - $28.18 803 8.89 24.15 193 21.55 $28.23 - $32.37 756 9.38 29.93 — — $40.61 - $40.61 158 9.47 40.61 — — 5,799 6.79 $ 16.57 2,901 $ 12.03 Restricted Stock Unit Activity A summary of the Company’s restricted stock units (“RSUs”) activity and weighted average exercise prices follows: Restricted Stock Unit Activity Number of Shares (in thousands) Weighted Average Grant Date Fair Value (Per Share) Aggregate Fair Value (in thousands) Balance outstanding at December 31, 2016 1,188 $ 8.44 $ 8,968 Awarded 332 8.16 — Released (363 ) 8.48 — Forfeited (284 ) 8.46 — Non-vested and outstanding at December 31, 2017 873 $ 8.29 $ 10,053 Balance outstanding at December 31, 2017 873 $ 8.29 $ 10,053 Awarded 2,568 17.02 — Released (361 ) 9.49 — Forfeited (390 ) 9.49 — Non-vested and outstanding at December 31, 2018 2,690 $ 15.81 $ 50,756 Balance outstanding at December 31, 2018 2,690 $ 15.81 $ 50,756 Awarded 1,979 30.99 — Released (1,197 ) 14.24 — Forfeited (423 ) 20.28 — Non-vested and outstanding at December 31, 2019 3,049 $ 24.73 $ 112,848 Expected to vest 2,059 $ 22.97 $ 76,185 RSUs granted to employees generally vest over a three to four -year period, or upon achievement of certain performance conditions. As of December 31, 2019 , total unrecognized compensation cost, adjusted for estimated forfeitures, related to nonvested RSUs was approximately $76.2 million and the weighted-average remaining vesting period was 2.8 years. As of December 31, 2019, the Company accrued approximately $19.0 million in cash awards to be settled in shares of the Company's stock and recorded a corresponding expense, which is included as a component of stock-based compensation expense in the accompanying consolidated financial statements. Stock-based compensation expense recognized in the Company’s consolidated statements of operations and cash flows was $44.1 million and $14.8 million for the years ended December 31, 2019 and 2018, respectively.

Income Taxes

Income Taxes	12 Months Ended
	Dec. 31, 2019
Income Tax Disclosure [Abstract]
Income Taxes	Income Taxes Income taxes are accounted for under the asset and liability method. Under this method, deferred tax assets and liabilities are recognized for the future tax consequences attributable to differences between the financial statement carrying amounts of existing assets and liabilities and their respective tax bases and operating loss and tax credit carryforwards. Deferred tax assets and liabilities are measured using enacted tax rates expected to apply to taxable income in the years in which those temporary differences are expected to be recovered or settled. In assessing the realizability of deferred tax assets, management considers whether it is more likely than not that some portion or all of the deferred tax assets will be realized. The ultimate realization of deferred tax assets is dependent upon the generation of future taxable income during the periods in which those temporary differences are expected to become deductible. Management considers the scheduled reversal of deferred tax liabilities, projected future taxable income and tax planning strategies in making this assessment. The Company includes interest accrued on the underpayment of income taxes in interest expense and penalties, if any, related to unrecognized tax benefits in general and administrative expenses. The Company recorded a valuation allowance against its U.S. deferred tax asset as it considered its cumulative loss in recent years as a significant piece of negative evidence. Since valuation allowances are evaluated on a jurisdiction by jurisdiction basis, we believe that the deferred tax assets related to LivePerson Australia, LivePerson UK, Kasamba Israel, LivePerson Japan and LivePerson LTD Israel are more likely than not to be realized as these jurisdictions have positive cumulative pre-tax book income after adjusting for permanent and onetime items. During the year ended December 31, 2019 , there was an increase in the valuation recorded of $19.1 million . Under Section 382 of the Internal Revenue Code of 1986, as amended (the ‘‘Code’’), the Company’s use of its federal net operating loss (“NOL”) carryforwards may be limited if the Company experiences an ownership change, as defined in Section 382 of the Code. Such an annual limitation could result in the expiration of the NOL carryforwards before utilization. Corresponding provisions of state law may limit the Company’s ability to utilize NOL carryforwards for state tax purposes. As of December 31, 2019, the Company had approximately $203.5 million of federal NOL carryforwards available to offset future taxable income. Included in this amount is $5.1 million of federal NOL carryovers from the Company’s acquisition of Proficient. Approximately $41.2 million of these federal NOL carryforwards were generated in taxable years ending on or before December 31, 2017 and will expire in various years through 2037. Federal NOL carryforwards generated in taxable years ending after December 31, 2017, do not expire, but generally may only offset up to 80% of federal taxable income earned in a taxable year. The domestic and foreign components of (loss) before provision for income taxes consist of the following (amounts in thousands): Year Ended December 31, 2019 2018 2017 United States $ (105,961 ) $ (38,078 ) $ (25,585 ) Israel 2,791 3,163 3,458 United Kingdom 5,377 3,690 2,087 Netherlands (465 ) 3,235 1,568 Australia 716 686 (1,979 ) Germany 3,854 2,900 2,424 Other (1) 462 230 337 $ (93,226 ) $ (24,174 ) $ (17,690 ) (1) Includes Japan, Italy, Singapore, Canada, France, India and Spain No additional provision has been made for U.S. income taxes on the undistributed earnings of its Israeli subsidiary, LivePerson Ltd. (formerly HumanClick Ltd.), as such earnings have been taxed in the U.S. and accumulated earnings of the Company’s other foreign subsidiaries are immaterial through December 31, 2019 . The provision for income taxes consists of the following (amounts in thousands): Year Ended December 31, 2019 2018 2017 Current income taxes: U.S. Federal $ (452 ) $ (1,932 ) $ — State and local 89 67 47 Foreign 4,415 3,032 2,852 Total current income taxes 4,052 1,167 2,899 Deferred income taxes: U.S. Federal 126 (295 ) (1,289 ) State and local 135 (28 ) (1,144 ) Foreign (1,468 ) 14 35 Total deferred income taxes (1,207 ) (309 ) (2,398 ) Total provision for income taxes $ 2,845 $ 858 $ 501 The difference between the total income taxes computed at the federal statutory rate and the provision for income taxes consists of the following: Year Ended December 31, 2019 2018 2017 Federal statutory rate 21.00 % 21.00 % 34.00 % State taxes, net of federal benefit 2.95 % 3.30 % 4.09 % Non-deductible expenses – stock based compensation 1.82 % 4.73 % (0.78 )% Global Intangible Low Tax Income Inclusion (2.29 )% (7.99 )% — % Non-deductible expenses – Other (1.57 )% (2.58 )% (1.19 )% Foreign taxes (1.86 )% (1.34 )% (1.97 )% Valuation allowance (26.42 )% (28.91 )% 26.12 % Stock based compensation - excess tax benefit 6.18 % 6.10 % — % Effect of new tax legislation — % — % (56.84 )% Other (2.86 )% 2.09 % (6.26 )% Total provision (3.05 )% (3.60 )% (2.83 )% The effects of temporary differences and federal NOL carryforwards that give rise to significant portions of federal deferred tax assets and deferred tax liabilities at December 31, 2019 and 2018 are presented below (amounts in thousands): Year Ended December 31, 2019 2018 Deferred tax assets: Net operating loss carryforwards $ 49,423 $ 18,083 Original Issue Discount 5,201 — Interest 875 — Operating lease liability 3,306 — Accounts payable and accrued expenses 5,934 4,024 Non-cash compensation 4,195 9,597 Intangibles amortization 3,273 5,691 Allowance for doubtful accounts 419 315 Total deferred tax assets 72,626 37,710 Less valuation allowance (48,451 ) (30,185 ) Deferred tax assets, net of valuation allowance 24,175 7,525 Deferred tax liabilities: Property and equipment (6,361 ) (3,736 ) Goodwill amortization and contingent earn-out adjustments (3,430 ) (4,172 ) Convertible Notes Issuance (11,055 ) — Operating lease right of use asset (2,504 ) — Total deferred tax liabilities (23,350 ) (7,908 ) Net deferred tax assets (liabilities) $ 825 $ (383 ) We have income tax NOL carryforwards related to federal and Australian income tax carryforwards of $203.5 million and $5.3 million respectively. The Australian NOLs can be carried forward indefinitely. $162.3 million of the federal NOLs can be carried forward indefinitely. $6.0 million of the federal NOLs will expire between 2023 and 2026, and $34.9 million will expire between 2036 and 2037. ASC Topic 740-10 clarifies the accounting for uncertainty in income taxes recognized in the financial statements in accordance with other provisions contained within this guidance. This topic prescribes a recognition threshold and a measurement attribute for the financial statement recognition and measurement of tax positions taken or expected to be taken in a tax return. For those benefits to be recognized, a tax position must be more likely than not to be sustained upon examination by the taxing authorities. The amount recognized is measured as the largest amount of benefit that is greater than 50% likely of being realized upon ultimate audit settlement. The Company had unrecognized tax benefits of $2 million and $1.9 million as of December 31, 2019 and 2018, respectively. Accrued interest and penalties included in the Company's liability related to unrecognized tax benefits were immaterial at December 31, 2019 and 2018. A reconciliation of the beginning and ending amount of unrecognized tax benefits is as follows (in thousands): Year Ended December 31, 2019 2018 Unrecognized tax benefits balance at January 1 $ 1,921 $ 4,924 Gross increase for tax positions of prior years — — Gross increase for tax positions of current years 584 405 Decrease due to expiration of statue (452 ) (445 ) Decrease due to settlement — (2,963 ) Gross unrecognized tax benefits at December 31 $ 2,053 $ 1,921 The tax years subject to examination by major tax jurisdictions include the years 2015 and forward for U.S states and New York City, the years 2016 and forward for U.S. Federal, and the years 2015 and forward for certain foreign jurisdictions. The decrease of $0.5 million was related to expiration of the statute of limitations. Tax Reform The Tax Cuts and Jobs Act makes broad and complex changes to the U.S. federal tax laws that affect fiscal 2017 , including, but not limited to requiring a one-time repatriation tax on certain unrepatriated earnings of foreign subsidiaries that is payable over eight years (the ‘‘Repatriation Tax’’). The Tax Cuts and Jobs Act also establishes new tax laws that will affect 2018 and later years, including, but not limited to, a reduction of the U.S. federal corporate income tax rate from a maximum of 34% to a flat rate of 21% , a general elimination of U.S. federal income taxes on certain dividends from foreign subsidiaries and a new provision designed to tax global intangible low-taxed income (‘‘GILTI’’). The legislation reduced the U.S. corporate tax rate from the current rate of 35% to 21% for tax years beginning after December 31, 2017 . Under the Tax Cuts and Jobs Act, the Company’s $32.8 million in federal NOL carryforwards generated as of December 31, 2017 will continue to be carried forward for 20 years following their incurrence and are expected to be available to fully offset taxable income earned in future tax years. Federal net operating losses generated after 2017 will be carried forward indefinitely, but generally may only offset up to 80% of taxable income earned in a tax year. In the quarter ending December 31, 2017 , the Company revalued its deferred tax assets and liabilities due to these changes, including (a) revaluing the Company’s federal net deferred tax assets before valuation allowance using the 21% tax rate, resulting in a decreased federal deferred tax provision of $10.1 million ; (b) revaluing the Company’s federal valuation allowance using the 21% tax rate, including the impact of tax planning strategies, resulting in a federal deferred tax benefit to continuing operations of $12.6 million ; (c) recognizing a federal deferred tax benefit of $2.0 million for 80% of indefinite lived deferred tax liabilities, which are anticipated to be available as a source of taxable income upon reversal of deferred tax assets that would also have indefinite lives; and (d) recognizing a $1.2 million state deferred tax provision unaffected by the changes in the Tax Cuts and Jobs Act. The new legislation requires the Company to pay federal income tax on the unremitted earnings of its foreign subsidiaries though December 31, 2017 . Pursuant to SAB 118, the Company estimated the tax on unremitted earnings is zero due to an overall accumulated deficit in earnings and profits. As of the fourth quarter of 2018, the Company has finalized the preparation and analysis of the required information and has not changed from the estimate. The Tax Cuts and Jobs Act creates a new requirement that certain income earned by a foreign subsidiary must be included in the federal taxable income of the U.S. shareholder. This income (called Global Intangible Low-Taxed Income, or GILTI) is defined as the excess of a foreign subsidiaries income over a nominal return on fixed assets. The Company expects to be subject to this inclusion in future years. Under U.S. GAAP, the Company is allowed to make an accounting policy choice of either accounting for the effects of the GILTI inclusion as a current period expense, when incurred, or factoring such amounts into the Company’s measurement of its deferred taxes. The Company has elected to treat the effects of this provision as a period cost, and therefore, has not considered the impacts of GILTI on its deferred tax liabilities at December 31, 2019. The Company’s consolidated financial statements do not provide for any related tax liability on amounts that may be repatriated from foreign operations as the Company intends for these earnings to be indefinitely reinvested in operations outside the U.S. Accordingly, no deferred taxes have been provided for the basis difference in the foreign subsidiaries.

Legal Matters

Legal Matters	12 Months Ended
	Dec. 31, 2019
Loss Contingency, Information about Litigation Matters [Abstract]
Legal Matters	Legal Matters The Company previously filed an intellectual property suit against [24]7 Customer, Inc. (‘‘[24]7’’) in the Southern District of New York on March 6, 2014 seeking damages on the grounds that [24]7 reverse engineered and misappropriated the Company’s technology to develop competing products and misused the Company’s business information. On June 22, 2015 , [24]7 Customer, Inc. filed suit against the Company in the Northern District of California alleging patent infringement. On December 7, 2015 , [24]7 Customer Inc. filed a second patent infringement suit against the Company, also in the Northern District of California. On March 16, 2017, the New York case was voluntarily transferred and consolidated with the two California cases in the Northern District of California for all pre-trial purposes. Rulings by both the Court and the United States Patent Office in the Company’s favor have invalidated the majority of [24]7 patents that were asserted in the patent cases. Trial for the Company’s intellectual property and other claims asserted against [24]7 in the original litigation is currently set for April 27, 2020 . Trial for [24]7’s patent infringement claims is currently set for March 15, 2021. The Company believes the claims filed by [24]7 are entirely without merit and intends to defend them vigorously. The Company routinely assesses all of its litigation and threatened litigation as to the probability of ultimately incurring a liability, and records its best estimate of the ultimate loss in situations where the Company assesses the likelihood of loss as probable. From time to time, the Company is involved in or subject to legal, administrative and regulatory proceedings, claims, demands and investigations arising in the ordinary course of business, including direct claims brought by or against the Company with respect to intellectual property, contracts, employment and other matters, as well as claims brought against the Company’s customers for whom the Company has a contractual indemnification obligation. The Company accrues for a liability when it is both probable that a liability has been incurred and the amount of the loss can be reasonably estimated. Significant judgment is required in both the determination of probability and the determination as to whether a loss is reasonably estimable. In addition, in the event the Company determines that a loss is not probable, but is reasonably possible, and it becomes possible to develop what the Company believes to be a reasonable range of possible loss, then the Company will include disclosure related to such matter as appropriate and in compliance with ASC 450. The accruals or estimates, if any, resulting from the foregoing analysis, are reviewed at least quarterly and adjusted to reflect the impact of negotiations, settlements, rulings, advice of legal counsel and other information and events pertaining to a particular matter. To the extent there is a reasonable possibility that the losses could exceed the amounts already accrued, the Company will, as applicable, adjust the accrual in the period the determination is made, disclose an estimate of the additional loss or range of loss, indicate that the estimate is immaterial with respect to its financial statements as a whole or, if the amount of such adjustment cannot be reasonably estimated, disclose that an estimate cannot be made. From time to time, third parties assert claims against the Company regarding intellectual property rights, privacy issues and other matters arising in the ordinary course of business. Although the Company cannot be certain of the outcome of any litigation or the disposition of any claims, nor the amount of damages and exposure, if any, that the Company could incur, the Company currently believes that the final disposition of all existing matters will not have a material adverse effect on our business, results of operations, financial condition or cash flows. In addition, in the ordinary course of business, the Company is also subject to periodic threats of lawsuits, investigations and claims. Regardless of the outcome, litigation can have an adverse impact on the Company because of defense and settlement costs, diversion of management resources and other factors.

Restructuring Costs

Restructuring Costs	12 Months Ended
	Dec. 31, 2019
Restructuring and Related Activities [Abstract]
Restructuring Costs	Restructuring Costs The Company’s restructuring costs relate to wind-down and severance costs associated with re-prioritizing and reallocating resources to focus on areas showing high growth potential, as well as the termination of a large customer contract. In 2019 , we undertook a restructuring related primarily to a reorganization in order to promote continued globalization of our technology operations, drive improvements in quality assurance of existing products and creation of new add-on features to LiveEngage. The expense associated with this restructuring was approximately $2.0 million , $4.5 million , and $2.6 million during the years ended December 31, 2019 , 2018 , and 2017 , respectively, and is classified in the consolidated statements of operations as restructuring costs. The restructuring liability was approximately $0.3 million and $1.0 million as of December 31, 2019 and 2018 , respectively, and is classified as accrued expenses and other current liabilities on the consolidated balance sheets. The following table presents the detail of the liability for the Company’s restructuring charges for the periods presented (amounts in thousands): December 31, 2019 December 31, 2018 Balance, Beginning of the year $ 977 $ 2,338 Severance and other associated costs 2,043 4,468 Cash payments (2,706 ) (5,829 ) Balance, End of year $ 314 $ 977 The following table presents the detail of expenses for the Company’s restructuring charges for the periods presented (amounts in thousands): December 31, 2019 December 31, 2018 December 31, 2017 Severance and other associated costs $ 2,043 $ 4,468 $ 648 Wind down costs of legacy platform — — 1,946 Total restructuring costs $ 2,043 $ 4,468 $ 2,594

Description of Business and S_2

Description of Business and Summary of Significant Accounting Policies (Policies)	12 Months Ended
	Dec. 31, 2019
Accounting Policies [Abstract]
Summary of Operations	LivePerson, Inc. (“LivePerson”, the “Company”, “we” or “our”) was incorporated in the State of Delaware in November 1995 and the LivePerson service was introduced in November 1998. In April 2000, the company completed an initial public offering and is currently traded on the NASDAQ Global Select Market and the Tel Aviv Stock Exchange. LivePerson is headquartered in New York City with U.S. offices in Alpharetta (Georgia), Austin (Texas), San Francisco (California) and Seattle (Washington), and international offices in Amsterdam (Netherlands), Berlin (Germany), Delhi (India), London (United Kingdom), Mannheim (Germany), Melbourne (Australia), Milan (Italy), Paris (France), Ra'anana (Israel), Reading (United Kingdom), Singapore (Singapore), Tel Aviv (Israel), and Tokyo (Japan). LivePerson makes life easier for people and brands everywhere through messaging powered by AI and humans. During the past decade, the consumer has made the mobile device the center of their digital lives, and they have made mobile messaging the center of communication with friends, family and peers. Our technology enables consumers to connect with businesses through these same preferred conversational interfaces, including Facebook Messenger, SMS, WhatsApp, Apple Business Chat, Google Rich Business Messenger and Alexa. These messaging conversations harness human agents, bots and Artificial Intelligence (AI) to power convenient, personalized and content-rich journeys across the entire consumer lifecycle, from discovery and research, to sales, service and support, and even marketing, social and brick and mortar engagements. For example, consumers can look up product info like ratings, images and pricing, search for stores, see product inventory, schedule appointments, apply for credit, approve repairs, make purchases or payments - all without ever leaving the messaging channel. These AI and human-assisted conversational experiences constitute the Conversational Space. LiveEngage, our enterprise-class cloud-based platform, enables businesses to become conversational by securely deploying messaging, coupled with bots and AI, at scale for brands with tens of millions of customers and many thousands of customer care agents. LiveEngage powers conversations across each of a brand’s primary digital channels, including mobile apps, mobile and desktop web browsers, short message service (SMS), social media and third-party consumer messaging platforms. Brands can also use LiveEngage to message consumers when they dial a 1-800 number instead of forcing them to navigate interactive voice response systems (IVRs) and wait on hold. Similarly, LiveEngage can ingest traditional emails and convert them into messaging conversations, or embed messaging conversations directly into web advertisements, rather than redirect consumers to static website landing pages. LivePerson's robust, cloud-based suite of rich messaging, real-time chat, AI and automation offerings features consumer and agent facing bots, intelligent routing and capacity mapping, real-time intent detection and analysis, queue prioritization, customer sentiment, analytics and reporting, content delivery, Payment Card Industry (PCI) compliance, cobrowsing and a sophisticated proactive targeting engine. With LiveEngage, agents can manage all conversations with consumers through a single console interface, regardless of which disparate messaging endpoints the consumers originate from; i.e., WhatsApp, Line, Apple Business Chat, IVR, social, email, Amazon Alexa, or WeChat. An extensible application programming interface (API) stack facilitates a lower cost of ownership by facilitating robust integration into back-end systems, as well as enabling developers to build their own programs and services on top of the platform. More than 40 APIs and software development kits are available on LiveEngage. LivePerson’s Conversational AI offerings put the power of bot development, training, management and analysis into the hands of the contact center and its agents, the teams most familiar with how to structure sales and service conversations to drive successful outcomes. The platform enables what we call “the tango” of humans, AI and bots, whereby human agents act as bot managers, overseeing AI-powered conversations and seamlessly stepping into the flow when a personal touch is needed. Agents become ultra-efficient, leveraging the AI engine to serve up relevant content, define next-best actions and take over repetitive transactional work, so that the agent can focus on relationship building. By seamlessly integrating messaging with our proprietary Conversational AI, as well as third-party bots, LiveEngage offers brands a comprehensive approach to scaling automations across their millions of customer conversations. LivePerson's consumer services offering is an online marketplace that connects independent service providers (Experts) who provide information and knowledge for a fee via mobile and online messaging with individual consumers (Users). Users seek assistance and advice in various categories including personal counseling and coaching, computers and programming, education and tutoring, spirituality and religion, and other topics.
Principles of Consolidation	Principles of Consolidation The consolidated financial statements reflect the operations of LivePerson and its wholly-owned subsidiaries. All significant intercompany balances and transactions have been eliminated in consolidation.
Use of Estimates	Use of Estimates The preparation of the consolidated financial statements in accordance with accounting principles generally accepted in the United States of America (“GAAP”) requires the Company’s management to make a number of estimates and assumptions relating to the reported amounts of assets and liabilities, 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 period. Significant items subject to such estimates and assumptions include revenue recognition, stock-based compensation, accounts receivable, the valuation of goodwill and intangible assets, income taxes and legal contingencies. Actual results could differ from those estimates.
Concentration of Credit Risk	Concentration of Credit Risk Financial instruments that potentially subject the Company to significant concentrations of credit risk consist primarily of cash and cash equivalents and accounts receivable which approximate fair value at December 31, 2019 because of the short-term nature of these instruments. The Company invests its cash and cash equivalents with financial institutions that it believes are of high quality, and the Company performs periodic evaluations of these instruments and the relative credit standings of the institutions with which it invests. At certain times, the Company’s cash balances with any one financial institution may exceed Federal Deposit Insurance Corporation insurance limits. The Company believes it mitigates its risk by depositing its cash balances with high credit, quality financial institutions.
Foreign Currency Translation	Foreign Currency Translation The Company’s operations are conducted in various countries around the world and the financial statements of its foreign subsidiaries are reported in the applicable foreign currencies (functional currencies). Financial information is translated from the applicable functional currency to the U.S. dollar (the reporting currency) for inclusion in the Company’s consolidated financial statements. Income, expenses and cash flows are translated at weighted average exchange rates prevailing during the fiscal period, and assets and liabilities are translated at fiscal period-end exchange rates. Resulting translation adjustments are included as a component of accumulated other comprehensive income (loss) in stockholders’ equity. Foreign exchange transaction gain or losses are included in Other Income (Expense), net in the accompanying consolidated statements of operations.
Cash and Cash Equivalents	Cash and Cash Equivalents The Company considers all highly liquid securities with original maturities of three months or less when acquired to be cash equivalents. Cash equivalents, which primarily consist of money market funds, are recorded at cost, which approximates fair value.
Accounts Receivable	Accounts Receivable
Property and Equipment	Property and Equipment Property and equipment are stated at cost, net of accumulated depreciation, and amortization. Depreciation and amortization is calculated using the straight-line method over the estimated useful lives of the related assets, generally three to five years
Internal-Use Software Development Costs	Internal-Use Software Development Costs In accordance with the Financial Accounting Standards Board (“FASB”) Accounting Standards Codification (“ASC”) 350-40, ‘‘Internal-Use Software’’, the Company capitalizes its costs to develop its internal use software when preliminary development efforts are successfully completed, management has authorized and committed project funding, and it is probable that the project will be completed and the software will be used as intended. These costs are included in property and equipment in the Company's consolidated balance sheets and are amortized on a straight-line basis over the estimated useful life of the related asset, which approximates five years
Goodwill and Intangible Assets	Goodwill and Intangible Assets The Company records goodwill when the consideration paid in a business combination exceeds the fair value of the net tangible assets and the identified intangible assets acquired. Goodwill is not amortized, but instead is required to be tested for impairment annually and whenever events or changes in circumstances indicate that the carrying value of goodwill may exceed its fair value. The Company performs testing for impairment of goodwill in its third quarter, or as events occur or circumstances change that would more likely than not reduce the fair value of the Company’s reporting units below their carrying amounts. A qualitative assessment is first made to determine whether it is necessary to perform the two-step quantitative goodwill impairment test. This initial qualitative assessment includes, among other things, consideration of: (i) market capitalization of the Company, (ii) past, current and projected future earnings and equity; (iii) recent trends and market conditions; and (iv) valuation metrics involving similar companies that are publicly-traded and acquisitions of similar companies, if available. If this initial qualitative assessment indicates that it is more likely than not that impairment exists, a second analysis will be performed, involving a comparison between the estimated fair values of the Company’s reporting unit with its respective carrying amount including goodwill. If the carrying value exceeds estimated fair value, there is an indication of potential impairment, and a third analysis is performed to measure the amount of impairment. The third analysis involves calculating an implied fair value of goodwill by measuring the excess of the estimated fair value of the reporting unit over the aggregate estimated fair values of the individual assets less liabilities. If the carrying value of goodwill exceeds the implied fair value of goodwill, an impairment charge is recorded for the excess. Intangible assets with estimable useful lives are amortized over their respective estimated useful lives to their estimated residual values, and reviewed for impairment in accordance with ASC 360-10-35, “Accounting for Impairment or Disposal of Long-Lived Assets.” The Company evaluates for goodwill impairment annually at September 30 th and at the end of the third quarter of 2019 , and 2018 , the Company determined that it was not more-likely that the fair value of the reporting units is less than their carrying amount. Accordingly, the Company did not perform the two-step goodwill impairment test on both the Company's Business and Consumer segments. The Company assessed qualitative facts while summarizing the totality of events and circumstances and considered the extent to which adverse events or circumstances could affect the reporting unit's fair value as well as the consideration of positive and mitigating events and circumstances that would affect the determination of whether it was more likely than not that the fair value of a reporting unit is less than its carrying amount.
Impairment of Long-Lived Assets	Impairment of Long-Lived Assets In accordance with ASC 360-10, “Accounting for the Impairment or Disposal of Long-lived Assets,” long-lived assets, such as property and equipment, and purchased intangibles subject to amortization are reviewed for impairment whenever events or changes in circumstances indicate that the carrying value of an asset may not be recoverable. The amount of any impairment is measured as the difference between the carrying value and the fair value of the impaired asset.
Revenue Recognition	Revenue Recognition The majority of the Company’s revenue is generated from monthly service revenues and related professional services from the sale of the LivePerson services. Revenues are recognized when control of these services is transferred to the Company's customers, in an amount that reflects the consideration the Company expects to be entitled to in exchange for those services. The Company determines revenue recognition through the following steps: • Identification of the contract, or contracts, with a customer; • Identification of the performance obligations in the contract; • Determination of the transaction price; • Allocation of the transaction price to the performance obligations in the contract; and • Recognition of revenue when, or as, the Company satisfies a performance obligation. Total revenue of $291.6 million , $249.8 million , and $218.9 million was recognized during the years ended December 31, 2019 , December 31, 2018 and December 31, 2017, respectively. The Company has made the following accounting policy election and elected to use a practical expedient specific to certain revenue streams, as permitted by the FASB, in applying Topic 606. The Company utilizes the right-to-invoice practical expedient with regard to the recognition of revenue upon the invoicing of certain revenue streams, as revenue for those streams are billed monthly. Under Topic 606, the Company defers all incremental commission costs ("contract acquisition costs") to obtain the contract. The contract acquisition costs, which are comprised of prepaid sales commissions, have balances at December 31, 2019 and 2018 of $32.0 million and $13.4 million , respectively. The Company amortizes these costs over the related period of benefit using the customer expected life that the Company determined to be three to five years which is consistent with the transfer to the customer of the services to which the asset relates. The Company classifies contract acquisition costs as long-term unless they have an original amortization period of one year or less. Hosted Services- Business Revenue Hosted Services Business revenue is reported at the amount that reflects the ultimate consideration expected to be received and primarily consist of fees that provide customers access to LiveEngage, the Company’s enterprise-class, cloud-based platform. The Company has determined such access represents a stand-ready service provided continually throughout the contract term. As such, control and satisfaction of this stand-ready performance obligation is deemed to occur over time. The Company recognizes this revenue over time on a ratable basis over the contract term, beginning on the date that access to the LiveEngage platform is made available to the customer. The passage of time is deemed to be the most faithful depiction of the transfer of control of the services as the customer simultaneously receives and consumes the benefit provided by the Company’s performance. Subscription contracts are generally one year or longer in length, billed, monthly, quarterly or annually in advance. There is no significant variable consideration related to these arrangements. Additionally, for certain of the Company’s larger customers, the Company may provide call center labor through an arrangement with one or more of several qualified vendors. For most of these customers, the Company passes the fee it incurs with the labor provider and its fee for the hosted services through to its customers in the form of a fixed fee for each order placed via the Company’s online engagement solutions. For these Pay for Performance (‘‘PFP’’) arrangements in accordance with ASC-606, ‘‘Principal Agent Considerations’’, the Company acts as a principal in a transaction if it controls the specified goods or services before they are transferred to the customer. Professional Services Revenues Professional services revenue primarily consists of fees for deployment and optimization services, as well as training delivered on an on-demand basis which is deemed to represent a distinct stand-ready performance obligation. Professional Services Revenues are reported at the amount that reflects the ultimate consideration the Company expects to receive in exchange for such services. Control for the majority of the Company’s Professional Services contracts passes over time to the customer and is recognized ratably over the contracted period, as the passage of time is deemed to be the most faithful depiction of the transfer of control. For certain deployment services, which are not deemed to represent a distinct performance obligation, revenue will be recognized in the same manner as the fee for access to the LiveEngage platform, and as such will be recognized on a straight-line basis over the contract term. For services billed on a fixed price basis, revenue is recognized over time based on the proportion performed using inputs as the measure of progress toward complete satisfaction of the performance obligation. Professional service contracts are generally one year or longer in length, billed, monthly, quarterly or annually in advance. There is no significant variable consideration related to these arrangements. Contracts with Multiple Performance Obligations Some of the Company’s contracts with customers contain multiple performance obligations. For these contracts, the Company accounts for individual performance obligations separately if they are distinct. The transaction price is allocated to the separate performance obligations on a relative standalone selling price basis. The Company determines the standalone selling prices based on its overall pricing objectives, taking into consideration market conditions and other factors, including the value of its contracts, the cloud applications sold, and the number and types of users within its contracts. Hosted Services- Consumer Revenue For revenue from the Company’s Consumer segment generated from online transactions between Experts and Users, revenue is recognized at an amount net of Expert fees in accordance with ASC 606, “Principal Agent Considerations,” due primarily to the fact that the Expert is the primary obligor. Additionally, the Company performs as an agent without any risk of loss for collection, and is not involved in selecting the Expert or establishing the Expert’s fee. The Company collects a fee from the consumer and retains a portion of the fee, and then remits the balance to the Expert. Revenue from these transactions is recognized at the point in time when the transaction is complete and no significant performance obligations remain. Deferred Revenues The Company records deferred revenues when cash payments are received or due in advance of its performance. The increase in the deferred revenue balance for the year ended December 31, 2019 is primarily driven by cash payments received or due in advance of satisfying its performance obligations, partially offset by $42.4 million of revenues recognized that were included in the deferred revenue balance as of December 31, 2018 . The following table presents deferred revenue by revenue source (amounts in thousands): December 31, 2019 2018 Hosted services – Business $ 82,892 $ 51,689 Hosted services – Consumer 687 543 Professional services – Business 5,172 2,783 Total deferred revenue - short term $ 88,751 $ 55,015 Hosted services – Business $ — $ 19 Professional services – Business 438 203 Total deferred revenue - long term $ 438 $ 222 Disaggregated Revenue The following table presents the Company's revenues disaggregated by revenue source (amounts in thousands): December 31, 2019 2018 2017 Revenue: Hosted services – Business $ 225,705 $ 197,474 $ 178,686 Hosted services – Consumer 24,480 19,553 17,450 Professional services 41,424 32,811 22,740 Total revenue $ 291,609 $ 249,838 $ 218,876 Revenue by Geographic Location The Company is domiciled in the United States and has international operations in the United Kingdom, Asia-Pacific, Latin America and Western Europe, particularly France and Germany. The following table presents the Company's revenues attributable to domestic and foreign operations for the years ended (amounts in thousands): December 31, 2019 2018 2017 United States $ 170,815 $ 146,702 $ 137,433 Other Americas (1) 11,462 7,315 6,987 Total Americas 182,277 154,017 144,420 EMEA (2) (4) 78,301 71,318 56,310 APAC (3) 31,031 24,503 18,146 Total revenue $ 291,609 $ 249,838 $ 218,876 (1) Canada, Latin America and South America (2) Europe, the Middle East and Africa (“EMEA”) (3) Asia-Pacific (“APAC”) (4) Includes revenue from the United Kingdom of $50.4 million , $46.5 million , and $38.9 million for the year ended December 31, 2019 , 2018 , and 2017 , respectively. and from the Netherlands of $10.0 million , $8.7 million , and $2.0 million for the year ended December 31, 2019 , 2018 , and 2017 , respectively. Information about Contract Balances Amounts collected in advance of services being provided are accounted for as deferred revenue. Nearly all of the Company's deferred revenue balance is related to Hosted Services- Business Revenue. In some arrangements, the Company allows customers to pay for access to LiveEngage over the term of the software license. The Company refers to these as subscription transactions. Amounts recognized as revenue in excess of amounts billed are recorded as unbilled receivables. Unbilled receivables, anticipated to be invoiced in the next twelve months, are included in accounts receivable on the consolidated balance sheet. The opening and closing balances of the Company's accounts receivable, unbilled receivables, and deferred revenues are as follows (amounts in thousands): Accounts Receivable Unbilled Receivable Contract Acquisition Costs noncurrent Deferred Revenue (current) Deferred Revenue (long term) Opening Balance as of December 31, 2018 $ 34,211 $ 11,812 $ 13,361 $ 55,015 $ 222 Increase (decrease), net 36,107 5,490 18,604 33,736 216 Ending Balance as of December 31, 2019 $ 70,318 $ 17,302 $ 31,965 $ 88,751 $ 438 As of December 31, 2019 , the Company expects to recognize the long term performance obligations in 2020.
Advertising Costs	Advertising Costs
Stock-based Compensation	Stock-based Compensation In accordance with ASC Topic 718 -10, ‘‘Stock Compensation’’, the Company measures stock based awards at fair value and recognizes compensation expense for all share-based payment awards made to its employees and directors, including employee stock options. The Company estimates the fair value of stock options granted using the Black-Scholes valuation model. This model requires the Company to make estimates and assumptions including, among other things, estimates regarding the length of time an employee will retain vested stock options before exercising them, the estimated volatility of its common stock price and the number of options that will be forfeited prior to vesting. The fair value is then recognized on a straight line basis over the requisite service period of the award, which is generally three to four years . Changes in these estimates and assumptions can materially affect the determination of the fair value of the stock-based compensation and consequently, the related amount recognized in the consolidated statement of operations.
Deferred Rent	Deferred Rent The Company records rent expense on a straight-line basis over the term of the related lease. The difference between the rent expense recognized for financial reporting purposes and the actual payments made in accordance with the lease agreement is recognized as deferred rent liability included in other liabilities on the Company’s consolidated balance sheets.
Income Taxes	Income Taxes Income taxes are accounted for under the asset and liability method. Under this method, deferred tax assets and liabilities are recognized for the future tax consequences attributable to differences between the financial statement carrying amounts of existing assets and liabilities and their respective tax bases and operating loss and tax credit carryforwards. Deferred tax assets and liabilities are measured using enacted tax rates expected to apply to taxable income in the years in which those temporary differences are expected to be recovered or settled. The effect on deferred tax assets and liabilities of a change in tax rates is recognized in results of operations in the period that the tax change occurs. In evaluating our ability to recover our deferred tax assets in the jurisdiction from which they arise, we consider all available positive and negative evidence, including scheduled reversals of deferred tax liabilities, projected future taxable income, tax-planning strategies, and results of recent operations. We include interest accrued on the underpayment of income taxes in interest expense and penalties, if any, related to unrecognized tax benefits in general and administrative expenses. Valuation allowances are established, when necessary, to reduce deferred tax assets to the amount expected to be realized
Comprehensive Loss	Comprehensive Loss In accordance with ASC 220, ‘‘Comprehensive Income’’, the Company reports by major components and as a single total, the change in its net assets during the period from non-owner sources. Comprehensive income (loss) consists of net income (loss), and accumulated other comprehensive income (loss), which includes certain changes in equity that are excluded from net income (loss). The Company’s comprehensive loss for all periods presented is related to the effect of foreign currency translation.
Recently Issued Accounting Standards	Recently Issued Accounting Standards In June 2016, the Financial Accounting Standards Board (“FASB”) issued Accounting Standards Update (‘‘ASU’’) 2016‑13, “Financial Instruments-Credit Losses: Measurement of Credit Losses on Financial Instruments,” which changes the impairment model for most financial assets. The new model uses a forward‑looking expected loss method, which will generally result in earlier recognition of allowances for losses. In November 2018, the FASB issued ASU 2018‑19, “Codification Improvements to Topic 326, Financial Instruments- Credit Losses,” which clarifies that receivables arising from operating leases are not within the scope of Topic 326, Financial Instruments-Credit Losses. Instead, impairment of receivables arising from operating leases should be accounted for in accordance with Topic 842, Leases . In April 2019, the FASB issued ASU 2019-04, ‘‘Codification Improvements to Topic 326, Financial Instruments-Credit Losses, Topic 815, Derivatives and Hedging, and Topic 825, Financial Instruments,’’ which clarifies treatment of certain credit losses. In May 2019, the FASB issued ASU 2019-05, ‘‘Financial Instruments - Credit Losses (Topic 326): Targeted Transition Relief,’’ which permits an entity, upon adoption of ASU 2016-13, to irrevocably elect the fair value option (on an instrument-by instrument basis) for eligible financial assets measured at amortized cost basis. These ASUs are effective for annual and interim periods beginning after January 1, 2020, and early adoption is permitted. The Company does not expect the adoption of this standard to have a material effect on our consolidated financial statements. In August 2018, the FASB issued ASU No. 2018-15, ‘‘Customer’s Accounting for Implementation Costs Incurred in a Cloud Computing Arrangement That Is a Service Contract; Disclosures for Implementation Costs Incurred for Internal-Use Software and Cloud Computing Arrangements’’ (“ASU 2018-15”). This standard aligns the accounting for implementation costs incurred in a hosting arrangement that is a service contract with the accounting for implementation costs incurred to develop or obtain internal-use software under Accounting Standards Codification (‘‘ASC’’) 350-40, in order to determine which costs to capitalize and recognize as an asset. ASU 2018-15 is effective for annual reporting periods, and interim periods within those years, beginning after December 15, 2019, and can be applied either prospectively to implementation costs incurred after the date of adoption or retrospectively to all arrangements. The Company is currently in the process of evaluating the impact of the adoption of ASU 2018-230 on its consolidated financial statements. In January 2017, FASB issued ASU No. 2017-04, ‘‘Intangibles -Goodwill and Other (Topic 350): Simplifying the Test for Goodwill Impairment’’ (“ASU 2017-04”). This update addresses concerns over the cost and complexity of the two-step goodwill impairment test. The amendments in this update remove the second step of the test. An entity will apply a one-step quantitative test and record the amount of goodwill impairment as the excess of a reporting unit's carrying amount over its fair value, not to exceed the total amount of goodwill allocated to the reporting unit. The new guidance does not amend the optional qualitative assessment of goodwill impairment. ASU 2017-04 is effective for financial statements issued for annual periods beginning after December 15, 2019, and interim periods within those annual periods. The Company does not expect the adoption of ASU 2017-04 will have a material effect on its financial position, results of operations or cash flows. Recently Adopted Accounting Pronouncements In February 2016, the FASB issued ASU No. 2016-02, “Leases” (“ASU 2016-02”). ASU 2016-02 requires lessees to recognize the following for all leases (with the exception of short-term leases) at the commencement date: a lease liability, which is a lessee’s obligation to make lease payments arising from a lease, measured on a discounted basis; and a right-of-use asset, which is an asset that represents the lessee’s right to use, or control the use of, a specified asset for the lease term. Under the new guidance, lessor accounting is largely unchanged. Lessees (for capital and operating leases) and lessors (for sales-type, direct financing, and operating leases) may apply a modified retrospective transition approach for leases existing at, or entered into after, the beginning of the earliest comparative period presented in the financial statements. The modified retrospective approach would not require any transition accounting for leases that expired before the earliest comparative period presented. The Company adopted ASU No. 2016-02, ‘‘Leases’’ (Topic 842), as of January 1, 2019 using the modified transition approach. The modified transition approach provides a method for recording existing leases at adoption. As a result, the Company was not required to adjust its comparative period financial information for effects of the standard or make the new required lease disclosures for periods before the date of adoption (i.e. January 1, 2019). For its long-term operating lease, the Company recognized a right-of-use asset and a lease liability on its balance sheet. The lease liability is determined as the present value of future lease payments using an estimated rate of interest that the Company would have to pay to borrow equivalent funds on a collateralized basis at the lease commencement date. The right-of-use asset is based on the liability adjusted for any prepaid or deferred rent. The lease term at the commencement date is determined by considering whether renewal options and termination options are reasonably assured of exercise. Rent expense for the operating lease is recognized on a straight-line basis over the lease term and is included in operating expenses on the statements of operations. Variable lease payments include lease operating expenses. The adoption of the new standard resulted in the recording of additional net lease assets and lease liabilities of approximately $10.0 million . The standard did not materially impact the Company's consolidated net earnings and had no impact on cash flows. In June 2018, the FASB issued ASU No. 2018-07, ‘‘Compensation -Stock Compensation (Topic 718) - Improvements to Nonemployee Share-Based Payment Accounting’’ (‘‘ASU 2018-07’’). This new standard expands the scope of Topic 718, Compensation-Stock Compensation (which currently only includes share-based payments to employees) to include share-based payments issued to non-employees for goods or services. Consequently, the accounting for share-based payments to non-employees and employees will be substantially aligned. ASU 2018-07 is effective for public companies for fiscal years beginning after December 15, 2018, including interim periods within that fiscal year. The standard did not materially impact the Company's consolidated net earnings and had no impact on cash flows. Impact on Previously Issued Financial Statements for the Correction of an Error During the quarter ended December 31, 2019, the Company identified and corrected an immaterial error that affected previously issued consolidated financial statements for the quarters ended March 31, June 30, and September 30, 2019 and 2018, respectively, and for the year ended December 31, 2018. The error related to the misapplication of U.S. generally accepted accounting principles relating to the classification of its contract acquisition costs for sales commissions. The Company previously recorded contract acquisition costs, a non current asset, as a component of prepaid expenses and other current assets. The effects of the above correction on the Company’s consolidated balance sheets is as follows (amounts in thousands): 2019 As of March 31, As of June 30, As of September 30, Prepaid expenses and other current assets As previously reported $ 29,290 $ 35,317 $ 41,806 Adjustment (16,808 ) (19,995 ) (25,993 ) As revised 12,482 15,322 15,813 Current assets As previously reported 318,362 311,511 300,746 Adjustment (16,808 ) (19,995 ) (25,993 ) As revised 301,554 291,516 274,753 Contract acquisition costs As previously reported — — — Adjustment 16,808 19,995 25,993 As revised 16,808 19,995 25,993 2018 As of As of June 30, As of As of Prepaid expenses and other current assets As previously reported $ 13,194 $ 16,885 $ 18,722 $ 22,613 Adjustment (5,539 ) (7,852 ) (10,880 ) (13,361 ) As revised 7,655 9,033 7,842 9,252 Current assets As previously reported 116,787 124,957 136,800 135,085 Adjustment (5,539 ) (7,852 ) (10,880 ) (13,361 ) As revised 111,248 117,105 125,920 121,724 Contract acquisition costs As previously reported — — — — Adjustment 5,539 7,852 10,880 13,361 As revised 5,539 7,852 10,880 13,361

Description of Business and S_3

Description of Business and Summary of Significant Accounting Policies (Tables)	12 Months Ended
	Dec. 31, 2019
Accounting Policies [Abstract]
Schedule of Activity in the Allowance for Doubtful Accounts	The activity in the allowance for doubtful accounts is as follows (amounts in thousands): Year Ended December 31, Beginning Balance Additions Charged to Costs and Expenses Deductions / Write-Offs Ending Balance 2017 $ 1,732 $ 1,895 $ (2,309 ) $ 1,318 2018 $ 1,318 $ 1,814 $ (856 ) $ 2,276 2019 $ 2,276 $ 2,159 $ (1,365 ) $ 3,070
Schedule of Deferred Revenue by Revenue Source	The following table presents deferred revenue by revenue source (amounts in thousands): December 31, 2019 2018 Hosted services – Business $ 82,892 $ 51,689 Hosted services – Consumer 687 543 Professional services – Business 5,172 2,783 Total deferred revenue - short term $ 88,751 $ 55,015 Hosted services – Business $ — $ 19 Professional services – Business 438 203 Total deferred revenue - long term $ 438 $ 222
Schedule of Disaggregated of Revenue	Disaggregated Revenue The following table presents the Company's revenues disaggregated by revenue source (amounts in thousands): December 31, 2019 2018 2017 Revenue: Hosted services – Business $ 225,705 $ 197,474 $ 178,686 Hosted services – Consumer 24,480 19,553 17,450 Professional services 41,424 32,811 22,740 Total revenue $ 291,609 $ 249,838 $ 218,876
Schedule of Revenue by Geographic Location	The following table presents the Company's revenues attributable to domestic and foreign operations for the years ended (amounts in thousands): December 31, 2019 2018 2017 United States $ 170,815 $ 146,702 $ 137,433 Other Americas (1) 11,462 7,315 6,987 Total Americas 182,277 154,017 144,420 EMEA (2) (4) 78,301 71,318 56,310 APAC (3) 31,031 24,503 18,146 Total revenue $ 291,609 $ 249,838 $ 218,876 (1) Canada, Latin America and South America (2) Europe, the Middle East and Africa (“EMEA”) (3) Asia-Pacific (“APAC”) (4) Includes revenue from the United Kingdom of $50.4 million , $46.5 million , and $38.9 million for the year ended December 31, 2019 , 2018 , and 2017 , respectively. and from the Netherlands of $10.0 million , $8.7 million , and $2.0 million for the year ended December 31, 2019 , 2018 , and 2017 , respectively.
Schedule of Receivables, Contract Acquisition Costs, and Deferred Revenue	The opening and closing balances of the Company's accounts receivable, unbilled receivables, and deferred revenues are as follows (amounts in thousands): Accounts Receivable Unbilled Receivable Contract Acquisition Costs noncurrent Deferred Revenue (current) Deferred Revenue (long term) Opening Balance as of December 31, 2018 $ 34,211 $ 11,812 $ 13,361 $ 55,015 $ 222 Increase (decrease), net 36,107 5,490 18,604 33,736 216 Ending Balance as of December 31, 2019 $ 70,318 $ 17,302 $ 31,965 $ 88,751 $ 438
Schedule of Impact of Correction on Previously Issued Consolidated Financial Statements	The effects of the above correction on the Company’s consolidated balance sheets is as follows (amounts in thousands): 2019 As of March 31, As of June 30, As of September 30, Prepaid expenses and other current assets As previously reported $ 29,290 $ 35,317 $ 41,806 Adjustment (16,808 ) (19,995 ) (25,993 ) As revised 12,482 15,322 15,813 Current assets As previously reported 318,362 311,511 300,746 Adjustment (16,808 ) (19,995 ) (25,993 ) As revised 301,554 291,516 274,753 Contract acquisition costs As previously reported — — — Adjustment 16,808 19,995 25,993 As revised 16,808 19,995 25,993 2018 As of As of June 30, As of As of Prepaid expenses and other current assets As previously reported $ 13,194 $ 16,885 $ 18,722 $ 22,613 Adjustment (5,539 ) (7,852 ) (10,880 ) (13,361 ) As revised 7,655 9,033 7,842 9,252 Current assets As previously reported 116,787 124,957 136,800 135,085 Adjustment (5,539 ) (7,852 ) (10,880 ) (13,361 ) As revised 111,248 117,105 125,920 121,724 Contract acquisition costs As previously reported — — — — Adjustment 5,539 7,852 10,880 13,361 As revised 5,539 7,852 10,880 13,361

Net Loss per Share (Tables)

Net Loss per Share (Tables)	12 Months Ended
	Dec. 31, 2019
Earnings Per Share [Abstract]
Reconciliation of Shares Used in Calculating Basic and Diluted Earnings Per Share	A reconciliation of shares used in calculating basic and diluted earnings per share follows: Year Ended December 31, 2019 2018 2017 Basic 62,593,026 59,203,400 56,358,017 Effect of assumed exercised options — — — Diluted 62,593,026 59,203,400 56,358,017

Segment Information (Tables)

Segment Information (Tables)	12 Months Ended
	Dec. 31, 2019
Segment Reporting [Abstract]
Summary Of Financial Information By Segment	Summarized financial information by segment for the year ended December 31, 2019 , based on the Company’s internal financial reporting system utilized by the Company’s chief operating decision maker, follows (amounts in thousands): Business Consumer Corporate Consolidated Revenue: Hosted services – Business $ 225,705 $ — $ — $ 225,705 Hosted services – Consumer — 24,480 — 24,480 Professional services – Business 41,424 — — 41,424 Total revenue 267,129 24,480 — 291,609 Cost of revenue 74,460 4,418 — 78,878 Sales and marketing 140,880 15,934 — 156,814 Amortization of purchased intangibles 1,794 — — 1,794 Unallocated corporate expenses — — 141,155 141,155 Operating income (loss) $ 49,995 $ 4,128 $ (141,155 ) $ (87,032 ) Summarized financial information by segment for the year ended December 31, 2018 , based on the Company’s internal financial reporting system utilized by the Company’s chief operating decision maker, follows (amounts in thousands): Business Consumer Corporate Consolidated Revenue: Hosted services – Business $ 197,474 $ — $ — $ 197,474 Hosted services – Consumer — 19,553 — 19,553 Professional services – Business 32,811 — — 32,811 Total revenue 230,285 19,553 — 249,838 Cost of revenue 58,420 4,059 — 62,479 Sales and marketing 94,339 9,005 — 103,344 Amortization of purchased intangibles 1,670 — — 1,670 Unallocated corporate expenses — — 106,048 106,048 Operating income (loss) $ 75,856 $ 6,489 $ (106,048 ) $ (23,703 ) Summarized financial information by segment for the year ended December 31, 2017 , based on the Company’s internal financial reporting system utilized by the Company’s chief operating decision maker, follows (amounts in thousands): Business Consumer Corporate Consolidated Revenue: Hosted services – Business $ 178,686 $ — $ — $ 178,686 Hosted services – Consumer — 17,450 — 17,450 Professional services – Business 22,740 — — 22,740 Total revenue 201,426 17,450 — 218,876 Cost of revenue 54,600 3,605 — 58,205 Sales and marketing 82,420 8,485 — 90,905 Amortization of purchased intangibles 1,840 — — 1,840 Unallocated corporate expenses — — 85,752 85,752 Operating income (loss) $ 62,566 $ 5,360 $ (85,752 ) $ (17,826 )
Long-Lived Assets By Geographic Region	The following table presents the Company's long-lived assets by geographic region for the periods presented (amounts in thousands): December 31, 2019 2018 United States $ 177,776 $ 128,647 Israel 16,680 14,140 Australia 13,765 9,529 Netherlands 7,705 7,452 Other (1) 18,677 8,611 Total long-lived assets $ 234,603 $ 168,379 (1) United Kingdom, Germany, Japan, France, Italy, Singapore, Canada, and Spain

Property and Equipment (Tables)

Property and Equipment (Tables)	12 Months Ended
	Dec. 31, 2019
Property, Plant and Equipment [Abstract]
Schedule of Property And Equipment	The following table presents the detail of property and equipment for the periods presented (amounts in thousands): December 31, 2019 2018 Computer equipment and software $ 92,493 $ 79,161 Furniture, equipment and building improvements 16,487 14,132 Internal-use software development costs 52,544 19,240 161,524 112,533 Less: accumulated depreciation and amortization (85,288 ) (68,798 ) Total $ 76,236 $ 43,735

Goodwill and Intangible Assets

Goodwill and Intangible Assets (Tables)	12 Months Ended
	Dec. 31, 2019
Goodwill and Intangible Assets Disclosure [Abstract]
Schedule of Changes in Goodwill	The changes in the carrying amount of goodwill for the year ended December 31, 2019 are as follows (amounts in thousands): Business Consumer Total Balance as of December 31, 2018 $ 87,007 $ 8,024 $ 95,031 Adjustments to goodwill: Foreign exchange adjustments (44 ) — (44 ) Balance as of December 31, 2019 $ 86,963 $ 8,024 $ 94,987 The changes in the carrying amount of goodwill for the year ended December 31, 2018 are as follows (amounts in thousands): Business Consumer Total Balance as of December 31, 2017 $ 72,507 $ 8,024 $ 80,531 Adjustments to goodwill: Acquisitions 14,606 — 14,606 Foreign exchange adjustments (106 ) — (106 ) Balance as of December 31, 2018 $ 87,007 $ 8,024 $ 95,031
Summary of Intangible Assets	Intangible assets are summarized as follows (see Note 8) (amounts in thousands): December 31, 2019 Gross Carrying Amount Accumulated Amortization Net Carrying Amount Weighted Average Amortization Period Amortizing intangible assets: Technology $ 30,413 $ (25,187 ) $ 5,226 5.3 years Customer relationships 16,964 (12,958 ) 4,006 8.4 years Patents 3,267 (714 ) 2,553 12.8 years Other 262 (235 ) 27 2.7 years Total $ 50,906 $ (39,094 ) $ 11,812 December 31, 2018 Gross Carrying Amount Accumulated Amortization Net Carrying Amount Weighted Average Amortization Period Amortizing intangible assets: Technology $ 30,447 $ (23,615 ) $ 6,832 5.3 years Customer relationships 17,219 (11,786 ) 5,433 8.4 years Patents 2,074 (534 ) 1,540 12.4 years Other 262 (235 ) 27 2.7 years Total $ 50,002 $ (36,170 ) $ 13,832
Schedule of Future Amortization Expense	Estimated amortization expense for the next five years are as follows (amounts in thousands): Estimated Amortization Expense 2020 $ 2,734 2021 2,520 2022 2,155 2023 904 2024 705 Thereafter 2,794 Total $ 11,812

Accrued Liabilities and Other_2

Accrued Liabilities and Other Current Liabilities (Tables)	12 Months Ended
	Dec. 31, 2019
Payables and Accruals [Abstract]
Schedule of Accrued Liabilities	The following table presents the detail of accrued liabilities and other current liabilities for the periods presented (amounts in thousands): December 31, 2019 2018 Payroll and other employee related costs $ 27,920 $ 19,014 Professional services, consulting and other vendor fees 20,382 17,461 Unrecognized tax benefits 2,053 1,913 Sales commissions 9,654 6,239 Contingent earn-out (Note 8) 557 2,372 Restructuring 314 977 Other 1,898 2,686 Total $ 62,778 $ 50,662

Convertible Senior Notes and _2

Convertible Senior Notes and Capped Call Transactions (Tables)	12 Months Ended
	Dec. 31, 2019
Debt Disclosure [Abstract]
Schedule of Carrying Amount of Convertible Debt and Related Interest	The net carrying amount of the liability component of the Notes was as follows (in thousands): As of December 31, 2019 Principal $ 230,000 Unamortized discount (45,295 ) Unamortized issuance costs (5,693 ) Net carrying amount $ 179,012 The net carrying amount of the equity component of the Notes was as follows (in thousands): As of December 31, 2019 Proceeds allocated to the conversion options (debt discount) $ 52,900 Issuance costs (1,986 ) Net carrying amount $ 50,914 The following table sets forth the interest expense recognized related to the Notes (in thousands): For the Year Ended December 31, 2019 Contractual interest expense $ 1,438 Amortization of issuance costs 956 Amortization of debt discount 7,605 Total interest expense $ 9,999

Fair Value Measurements (Tables

Fair Value Measurements (Tables)	12 Months Ended
	Dec. 31, 2019
Fair Value Disclosures [Abstract]
Schedule of Assets and Liabilities Measured at Fair Value on Recurring Basis	The Company's assets and liabilities that are measured at fair value on a recurring basis, by level, within the fair value hierarchy as of December 31, 2019 and December 31, 2018 , are summarized as follows (amounts in thousands). December 31, 2019 December 31, 2018 Level 1 Level 2 Level 3 Total Level 1 Level 2 Level 3 Total Assets: Cash equivalents: Money market funds $ 2,899 $ — $ — $ 2,899 $ 2,828 $ — $ — $ 2,828 Total assets $ 2,899 $ — $ — $ 2,899 $ 2,828 $ — $ — $ 2,828 Liabilities: Contingent earn-out $ — $ — $ 557 $ 557 $ — $ — $ 2,372 $ 2,372 Total liabilities $ — $ — $ 557 $ 557 $ — $ — $ 2,372 $ 2,372
Schedule of Changes in Fair Value of Level 3 Liabilities	The changes in fair value of the Level 3 liabilities are as follows (amounts in thousands): Contingent Earn-Out December 31, 2019 2018 Balance, Beginning of year $ 2,372 $ — Conversable, Inc. fair value adjustment (see Note 7) (496 ) 1,496 AdvantageTec, Inc. fair value adjustment (see Note 7) 168 876 Payments (1,487 ) — Balance, End of year $ 557 $ 2,372
Schedule of Gains (Losses) on Derivative Instruments Recognized in the Income Statement	The following summarizes certain information regarding the Company’s derivatives that are not designated or are not effective as hedges (in thousands): Gain (losses) on Derivative Instruments Recognized in the Statement of Operations Statement of Operations Location December 31, 2019 December 31, 2018 December 31, 2017 Foreign currency derivatives contracts Other Income (Expense), net $ — $ (50 ) $ 236

Commitments and Contingencies (

Commitments and Contingencies (Tables)	12 Months Ended
	Dec. 31, 2019
Commitments and Contingencies Disclosure [Abstract]
Schedule of Lease Information	The determination of the discount rate used to calculate the present value of the right-of-use assets and lease liabilities depends on whether an interest rate is specified in the lease or not. If the lease specifies a rate, that rate is used when calculating the present value of lease payments. If the rate is not readily determinable, which is generally the case for the Company, the Company’s incremental borrowing rate (“IBR”) as of the date of inception of the lease is used (for initial measurement, the IBR was determined as of the adoption date of the standard). The IBR is the rate of interest that the Company would have to pay to borrow on a collateralized basis over a similar term and amount equal to the lease payments in a similar economic environment. The Company used a ratings benchmark report against its peers in the technology sector. The Company has operating leases for its corporate offices and other service agreements. The Company's leases have remaining lease terms of 1 to 12 years , some of which include options to extend. The Company's lease expense for the year ended December 31, 2019 consisted entirely of operating leases was approximately $13.0 million . Operating lease payments, which reduced operating cash flows for the year ended December 31, 2019 was approximately $7.0 million . Supplemental balance sheet information related to leases was as follows: As of December 31, 2019 Operating Leases (in thousands, except lease term and discount rate) Right-of-use asset, net $ 15,680 Current operating lease liability 6,602 Long term operating lease liability 12,865 Total operating lease liability $ 19,467 Weighted Average Remaining Lease Term Operating leases 3.5 years Weighted Average Discount Rate Operating leases 7 %
Schedule of Future Minimum Lease Payments Under Non-Cancelable Operating Leases	Future minimum lease payments under non-cancellable operating leases (with an initial or remaining lease terms in excess of one year) are as follows (amounts in thousands): Year Ending December 31, Operating Leases 2020 $ 7,787 2021 6,530 2022 3,746 2023 1,925 2024 1,148 Thereafter 864 Total minimum lease payments $ 22,000 Less: present value adjustment (2,533 ) Total operating lease liability $ 19,467

Stockholders' Equity (Tables)

Stockholders' Equity (Tables)	12 Months Ended
	Dec. 31, 2019
Equity [Abstract]
Weighted Average Assumptions of Fair Value Options Using Black-Scholes Option-Pricing Model	The fair value of each option grant is estimated on the date of grant using the Black-Scholes option-pricing model with the following weighted average assumptions for the years ended December 31, 2019 , 2018 and 2017 : December 31, 2019 2018 2017 Dividend yield —% —% —% Risk-free interest rate 1.66% – 3.05% 2.5% – 3.1% 1.7% – 2.1% Expected life (in years) 5.0 5.0 5.0 Historical volatility 43.42% – 44% 43.5% – 48.4% 46.6% – 48.1%
Schedule of Stock Option Activity and Weighted Average Exercise Prices	A summary of the Company’s stock option activity and weighted average exercise prices follows: Stock Option Activity Weighted Average Remaining Contractual Term (in years) Aggregate Intrinsic Value (in thousands) Options (in thousands) Weighted Balance outstanding at December 31, 2016 7,769 $ 10.88 Granted 2,042 9.87 Exercised (854 ) 8.80 Cancelled or expired (998 ) 11.98 Balance outstanding at December 31, 2017 7,959 $ 10.71 5.85 $ 14,881 Options vested and expected to vest 7,163 $ 10.75 5.49 $ 13,197 Options exercisable at December 31, 2017 5,163 $ 11.17 4.50 $ 8,648 Balance outstanding at December 31, 2017 7,959 $ 10.71 Granted 2,033 15.00 Exercised (3,120 ) 10.70 Cancelled or expired (606 ) 10.03 Balance outstanding at December 31, 2018 6,266 $ 12.13 6.55 $ 43,348 Options vested and expected to vest 5,550 $ 11.89 6.28 $ 39,521 Options exercisable at December 31, 2018 3,278 $ 11.12 4.64 $ 25,367 Balance outstanding at December 31, 2018 6,266 $ 12.13 Granted 1,425 29.76 Exercised (1,523 ) 11.12 Cancelled or expired (369 ) 14.76 Balance outstanding at December 31, 2019 5,799 $ 16.57 6.79 $ 119,064 Options vested and expected to vest 5,096 $ 15.29 6.49 $ 110,934 Options exercisable at December 31, 2019 2,901 $ 12.03 4.95 $ 72,424
Schedule of Share-based Compensation, Shares Authorized under Stock Option Plans, by Exercise Price Range	The following table summarizes information about outstanding and vested stock options as of December 31, 2019 : Options Outstanding Options Exercisable Range of Exercise Prices Number of Shares Outstanding (in thousands) Weighted-Average Remaining Contractual Life (Years) Weighted-Average Exercise Price Number of Shares (in thousands) Weighted-Average Exercise Price $6.23 - $7.6 643 6.37 $ 7.42 392 $ 7.40 $7.95 - $10.05 648 4.83 9.47 604 9.48 $10.13 - $11.95 621 5.93 10.85 476 10.53 $11.96 - $12.32 50 1.51 12.10 50 12.10 $12.45 - $12.45 782 7.91 12.45 287 12.45 $12.46 - $14.3 758 3.62 13.57 628 13.41 $14.5 - $17.88 580 6.44 16.11 271 16.60 $18.09 - $28.18 803 8.89 24.15 193 21.55 $28.23 - $32.37 756 9.38 29.93 — — $40.61 - $40.61 158 9.47 40.61 — — 5,799 6.79 $ 16.57 2,901 $ 12.03
Schedule of Share-based Compensation, Restricted Stock Units Award Activity	Restricted Stock Unit Activity A summary of the Company’s restricted stock units (“RSUs”) activity and weighted average exercise prices follows: Restricted Stock Unit Activity Number of Shares (in thousands) Weighted Average Grant Date Fair Value (Per Share) Aggregate Fair Value (in thousands) Balance outstanding at December 31, 2016 1,188 $ 8.44 $ 8,968 Awarded 332 8.16 — Released (363 ) 8.48 — Forfeited (284 ) 8.46 — Non-vested and outstanding at December 31, 2017 873 $ 8.29 $ 10,053 Balance outstanding at December 31, 2017 873 $ 8.29 $ 10,053 Awarded 2,568 17.02 — Released (361 ) 9.49 — Forfeited (390 ) 9.49 — Non-vested and outstanding at December 31, 2018 2,690 $ 15.81 $ 50,756 Balance outstanding at December 31, 2018 2,690 $ 15.81 $ 50,756 Awarded 1,979 30.99 — Released (1,197 ) 14.24 — Forfeited (423 ) 20.28 — Non-vested and outstanding at December 31, 2019 3,049 $ 24.73 $ 112,848 Expected to vest 2,059 $ 22.97 $ 76,185

Income Taxes (Tables)

Income Taxes (Tables)	12 Months Ended
	Dec. 31, 2019
Income Tax Disclosure [Abstract]
Schedule of Domestic and Foreign Components of Income Before Provision for Income Taxes	The domestic and foreign components of (loss) before provision for income taxes consist of the following (amounts in thousands): Year Ended December 31, 2019 2018 2017 United States $ (105,961 ) $ (38,078 ) $ (25,585 ) Israel 2,791 3,163 3,458 United Kingdom 5,377 3,690 2,087 Netherlands (465 ) 3,235 1,568 Australia 716 686 (1,979 ) Germany 3,854 2,900 2,424 Other (1) 462 230 337 $ (93,226 ) $ (24,174 ) $ (17,690 ) (1) Includes Japan, Italy, Singapore, Canada, France, India and Spain
Schedule of Provision For Income Taxes	The provision for income taxes consists of the following (amounts in thousands): Year Ended December 31, 2019 2018 2017 Current income taxes: U.S. Federal $ (452 ) $ (1,932 ) $ — State and local 89 67 47 Foreign 4,415 3,032 2,852 Total current income taxes 4,052 1,167 2,899 Deferred income taxes: U.S. Federal 126 (295 ) (1,289 ) State and local 135 (28 ) (1,144 ) Foreign (1,468 ) 14 35 Total deferred income taxes (1,207 ) (309 ) (2,398 ) Total provision for income taxes $ 2,845 $ 858 $ 501
Schedule of Reconciliation of Federal Statutory Tax Rate to Effective Income Tax Rate	The difference between the total income taxes computed at the federal statutory rate and the provision for income taxes consists of the following: Year Ended December 31, 2019 2018 2017 Federal statutory rate 21.00 % 21.00 % 34.00 % State taxes, net of federal benefit 2.95 % 3.30 % 4.09 % Non-deductible expenses – stock based compensation 1.82 % 4.73 % (0.78 )% Global Intangible Low Tax Income Inclusion (2.29 )% (7.99 )% — % Non-deductible expenses – Other (1.57 )% (2.58 )% (1.19 )% Foreign taxes (1.86 )% (1.34 )% (1.97 )% Valuation allowance (26.42 )% (28.91 )% 26.12 % Stock based compensation - excess tax benefit 6.18 % 6.10 % — % Effect of new tax legislation — % — % (56.84 )% Other (2.86 )% 2.09 % (6.26 )% Total provision (3.05 )% (3.60 )% (2.83 )%
Schedule of Federal Deferred Tax Assets and Deferred Tax Liabilities	The effects of temporary differences and federal NOL carryforwards that give rise to significant portions of federal deferred tax assets and deferred tax liabilities at December 31, 2019 and 2018 are presented below (amounts in thousands): Year Ended December 31, 2019 2018 Deferred tax assets: Net operating loss carryforwards $ 49,423 $ 18,083 Original Issue Discount 5,201 — Interest 875 — Operating lease liability 3,306 — Accounts payable and accrued expenses 5,934 4,024 Non-cash compensation 4,195 9,597 Intangibles amortization 3,273 5,691 Allowance for doubtful accounts 419 315 Total deferred tax assets 72,626 37,710 Less valuation allowance (48,451 ) (30,185 ) Deferred tax assets, net of valuation allowance 24,175 7,525 Deferred tax liabilities: Property and equipment (6,361 ) (3,736 ) Goodwill amortization and contingent earn-out adjustments (3,430 ) (4,172 ) Convertible Notes Issuance (11,055 ) — Operating lease right of use asset (2,504 ) — Total deferred tax liabilities (23,350 ) (7,908 ) Net deferred tax assets (liabilities) $ 825 $ (383 )
Schedule of Unrecognized Tax Benefits Roll Forward	A reconciliation of the beginning and ending amount of unrecognized tax benefits is as follows (in thousands): Year Ended December 31, 2019 2018 Unrecognized tax benefits balance at January 1 $ 1,921 $ 4,924 Gross increase for tax positions of prior years — — Gross increase for tax positions of current years 584 405 Decrease due to expiration of statue (452 ) (445 ) Decrease due to settlement — (2,963 ) Gross unrecognized tax benefits at December 31 $ 2,053 $ 1,921

Restructuring Costs (Tables)

Restructuring Costs (Tables)	12 Months Ended
	Dec. 31, 2019
Restructuring and Related Activities [Abstract]
Schedule of Restructuring and Related Costs	The following table presents the detail of the liability for the Company’s restructuring charges for the periods presented (amounts in thousands): December 31, 2019 December 31, 2018 Balance, Beginning of the year $ 977 $ 2,338 Severance and other associated costs 2,043 4,468 Cash payments (2,706 ) (5,829 ) Balance, End of year $ 314 $ 977 The following table presents the detail of expenses for the Company’s restructuring charges for the periods presented (amounts in thousands): December 31, 2019 December 31, 2018 December 31, 2017 Severance and other associated costs $ 2,043 $ 4,468 $ 648 Wind down costs of legacy platform — — 1,946 Total restructuring costs $ 2,043 $ 4,468 $ 2,594

Description of Business and S_4

Description of Business and Summary of Significant Accounting Policies - Narrative (Details) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2019	Dec. 31, 2018	Dec. 31, 2017	Jan. 01, 2019
Organization Consolidation And Summary Of Significant Accounting Policies [Line Items]
Accounts receivable	$ 87,620	$ 46,023
Depreciation and amortization expense	16,366	14,188	$ 12,358
Capitalized computer software	29,100	11,700	8,300
Total revenue	291,609	249,838	218,876
Prepaid commissions	32,000	13,400
Revenues recognized that were included in the deferred revenue balance	42,400
Advertising costs	28,600	$ 17,400	$ 15,800
Operating lease right of use asset	15,680
Operating lease liability	$ 19,467
Software and software development costs
Organization Consolidation And Summary Of Significant Accounting Policies [Line Items]
Property and equipment, useful life	5 years
Minimum
Organization Consolidation And Summary Of Significant Accounting Policies [Line Items]
Amortization period for prepaid commissions (in years)	3 years
Requisite service period	3 years
Minimum | Computer equipment and software
Organization Consolidation And Summary Of Significant Accounting Policies [Line Items]
Property and equipment, useful life	3 years
Maximum
Organization Consolidation And Summary Of Significant Accounting Policies [Line Items]
Amortization period for prepaid commissions (in years)	5 years
Requisite service period	4 years
Maximum | Computer equipment and software
Organization Consolidation And Summary Of Significant Accounting Policies [Line Items]
Property and equipment, useful life	5 years
ASU No. 2016-02
Organization Consolidation And Summary Of Significant Accounting Policies [Line Items]
Operating lease right of use asset				$ 10,000
Operating lease liability				$ 10,000
Customer Concentration Risk | Accounts Receivable | Two customers
Organization Consolidation And Summary Of Significant Accounting Policies [Line Items]
Accounts receivable	$ 17,600

Description of Business and S_5

Description of Business and Summary of Significant Accounting Policies - Accounts Receivable (Details) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2019	Dec. 31, 2018	Dec. 31, 2017
Allowance for doubtful accounts
Beginning Balance	$ 2,276	$ 1,318	$ 1,732
Additions Charged to Costs and Expenses	2,159	1,814	1,895
Deductions / Write-Offs	(1,365)	(856)	(2,309)
Ending Balance	$ 3,070	$ 2,276	$ 1,318

Description of Business and S_6

Description of Business and Summary of Significant Accounting Policies - Deferred Revenue (Details) - USD ($) $ in Thousands	Dec. 31, 2019	Dec. 31, 2018
Disaggregation of Revenue [Line Items]
Total deferred revenue - short term	$ 88,751	$ 55,015
Total deferred revenue - long term	438	222
Hosted Services - Business
Disaggregation of Revenue [Line Items]
Total deferred revenue - short term	82,892	51,689
Total deferred revenue - long term	0	19
Hosted Services - Consumer
Disaggregation of Revenue [Line Items]
Total deferred revenue - short term	687	543
Professional Services - Business
Disaggregation of Revenue [Line Items]
Total deferred revenue - short term	5,172	2,783
Total deferred revenue - long term	$ 438	$ 203

Description of Business and S_7

Description of Business and Summary of Significant Accounting Policies - Disaggregation of Revenue (Details) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2019	Dec. 31, 2018	Dec. 31, 2017
Disaggregation of Revenue [Line Items]
Total revenue	$ 291,609	$ 249,838	$ 218,876
Hosted Services - Business
Disaggregation of Revenue [Line Items]
Total revenue	225,705	197,474	178,686
Hosted Services - Consumer
Disaggregation of Revenue [Line Items]
Total revenue	24,480	19,553	17,450
Professional Services
Disaggregation of Revenue [Line Items]
Total revenue	$ 41,424	$ 32,811	$ 22,740

Description of Business and S_8

Description of Business and Summary of Significant Accounting Policies - Revenue by Geographic Region (Details) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2019	Dec. 31, 2018	Dec. 31, 2017
Disaggregation of Revenue [Line Items]
Total revenue	$ 291,609	$ 249,838	$ 218,876
United States
Disaggregation of Revenue [Line Items]
Total revenue	170,815	146,702	137,433
Other Americas
Disaggregation of Revenue [Line Items]
Total revenue	11,462	7,315	6,987
Total Americas
Disaggregation of Revenue [Line Items]
Total revenue	182,277	154,017	144,420
EMEA
Disaggregation of Revenue [Line Items]
Total revenue	78,301	71,318	56,310
APAC
Disaggregation of Revenue [Line Items]
Total revenue	31,031	24,503	18,146
United Kingdom
Disaggregation of Revenue [Line Items]
Total revenue	50,400	46,500	38,900
Netherlands
Disaggregation of Revenue [Line Items]
Total revenue	$ 10,000	$ 8,700	$ 2,000

Description of Business and S_9

Description of Business and Summary of Significant Accounting Policies Description of Business and Summary of Significant Accounting Policies - Receivables and Deferred Revenue (Details) $ in Thousands	12 Months Ended
	Dec. 31, 2019USD ($)
Contract Balances [Roll Forward]
Opening balance, Receivable	$ 46,023
Closing balance, Receivable	87,620
Opening balance, Contract Acquisition Costs noncurrent	13,400
Closing balance, Contract Acquisition Costs noncurrent	32,000
Opening balance, Deferred Revenue (current)	55,015
Increase (decrease) in current deferred revenue (current)	33,736
Closing balance, Deferred Revenue (current)	88,751
Ending balance, Deferred revenue (long-term)	222
Increase (decrease) in long-term deferred revenue, net	216
Closing balance, Deferred revenue (long-term)	438
Accounts Receivable
Contract Balances [Roll Forward]
Opening balance, Receivable	34,211
Increase (decrease) in accounts receivable, net	36,107
Closing balance, Receivable	70,318
Unbilled Receivable
Contract Balances [Roll Forward]
Opening balance, Receivable	11,812
Increase (decrease) in unbilled receivable, net	5,490
Closing balance, Receivable	17,302
Opening balance, Contract Acquisition Costs noncurrent	13,361
Increase (decrease) in contract acquisition costs noncurrent	18,604
Closing balance, Contract Acquisition Costs noncurrent	$ 31,965

Description of Business and _10

Description of Business and Summary of Significant Accounting Policies - Reclassification (Details) - USD ($) $ in Thousands	Dec. 31, 2019	Sep. 30, 2019	Jun. 30, 2019	Mar. 31, 2019	Dec. 31, 2018	Sep. 30, 2018	Jun. 30, 2018	Mar. 31, 2018
Reclassification [Line Items]
Prepaid expenses and other current assets	$ 13,964	$ 15,813	$ 15,322	$ 12,482	$ 9,252	$ 7,842	$ 9,033	$ 7,655
Current assets	278,107	274,753	291,516	301,554	121,724	125,920	117,105	111,248
Contract acquisition costs	$ 31,965	25,993	19,995	16,808	13,361	10,880	7,852	5,539
As previously reported
Reclassification [Line Items]
Prepaid expenses and other current assets		41,806	35,317	29,290	22,613	18,722	16,885	13,194
Current assets		300,746	311,511	318,362	135,085	136,800	124,957	116,787
Contract acquisition costs		0	0	0	0	0	0	0
Adjustment
Reclassification [Line Items]
Prepaid expenses and other current assets		(25,993)	(19,995)	(16,808)	(13,361)	(10,880)	(7,852)	(5,539)
Current assets		(25,993)	(19,995)	(16,808)	(13,361)	(10,880)	(7,852)	(5,539)
Contract acquisition costs		$ 25,993	$ 19,995	$ 16,808	$ 13,361	$ 10,880	$ 7,852	$ 5,539

Net Loss per Share (Details)

Net Loss per Share (Details) - shares	12 Months Ended
	Dec. 31, 2019	Dec. 31, 2018	Dec. 31, 2017
Earnings Per Share [Abstract]
Shares excluded from computation of earnings per share (in shares)	8,848,907	8,957,672	8,831,798
Weighted Average Number of Shares Outstanding
Basic (in shares)	62,593,026	59,203,400	56,358,017
Effect of assumed exercised options (in shares)	0	0	0
Diluted (in shares)	62,593,026	59,203,400	56,358,017

Segment Information - Narrative

Segment Information - Narrative (Details)	12 Months Ended
	Dec. 31, 2019segment
Segment Reporting [Abstract]
Number of operating segments	2

Segment Information - Summary o

Segment Information - Summary of Financial Information By Segment (Details) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2019	Dec. 31, 2018	Dec. 31, 2017
Segment Reporting Information [Line Items]
Total revenue	$ 291,609	$ 249,838	$ 218,876
Cost of revenue	78,878	62,479	58,205
Sales and marketing	156,814	103,344	90,905
Amortization of purchased intangibles	1,794	1,670	1,840
Unallocated corporate expenses	141,155	106,048	85,752
Loss from operations	(87,032)	(23,703)	(17,826)
Corporate
Segment Reporting Information [Line Items]
Unallocated corporate expenses	141,155	106,048	85,752
Loss from operations	(141,155)	(106,048)	(85,752)
Business | Operating Segments
Segment Reporting Information [Line Items]
Total revenue	267,129	230,285	201,426
Cost of revenue	74,460	58,420	54,600
Sales and marketing	140,880	94,339	82,420
Amortization of purchased intangibles	1,794	1,670	1,840
Loss from operations	49,995	75,856	62,566
Consumer | Operating Segments
Segment Reporting Information [Line Items]
Total revenue	24,480	19,553	17,450
Cost of revenue	4,418	4,059	3,605
Sales and marketing	15,934	9,005	8,485
Loss from operations	4,128	6,489	5,360
Hosted Services - Business
Segment Reporting Information [Line Items]
Total revenue	225,705	197,474	178,686
Hosted Services - Business | Business | Operating Segments
Segment Reporting Information [Line Items]
Total revenue	225,705	197,474	178,686
Hosted Services - Consumer
Segment Reporting Information [Line Items]
Total revenue	24,480	19,553	17,450
Hosted Services - Consumer | Consumer | Operating Segments
Segment Reporting Information [Line Items]
Total revenue	24,480	19,553	17,450
Professional Services - Business
Segment Reporting Information [Line Items]
Total revenue	41,424	32,811	22,740
Professional Services - Business | Business | Operating Segments
Segment Reporting Information [Line Items]
Total revenue	$ 41,424	$ 32,811	$ 22,740

Segment Information - Long-Live

Segment Information - Long-Lived Assets By Geographic Region (Details) - USD ($) $ in Thousands	Dec. 31, 2019	Dec. 31, 2018
Segment Reporting Information [Line Items]
Total long-lived assets	$ 234,603	$ 168,379
United States
Segment Reporting Information [Line Items]
Total long-lived assets	177,776	128,647
Israel
Segment Reporting Information [Line Items]
Total long-lived assets	16,680	14,140
Australia
Segment Reporting Information [Line Items]
Total long-lived assets	13,765	9,529
Netherlands
Segment Reporting Information [Line Items]
Total long-lived assets	7,705	7,452
Other
Segment Reporting Information [Line Items]
Total long-lived assets	$ 18,677	$ 8,611

Property and Equipment - Balanc

Property and Equipment - Balances (Details) - USD ($) $ in Thousands	Dec. 31, 2019	Dec. 31, 2018
Property and Equipment, Net
Property and equipment gross	$ 161,524	$ 112,533
Less: accumulated depreciation and amortization	(85,288)	(68,798)
Total	76,236	43,735
Computer equipment and software
Property and Equipment, Net
Property and equipment gross	92,493	79,161
Furniture, equipment and building improvements
Property and Equipment, Net
Property and equipment gross	16,487	14,132
Internal-use software development costs
Property and Equipment, Net
Property and equipment gross	$ 52,544	$ 19,240

Property and Equipment - Narrat

Property and Equipment - Narrative (Details) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2019	Dec. 31, 2018	Dec. 31, 2017
Property, Plant and Equipment [Abstract]
Internal-use software development costs not yet subject to amortization	$ 25,300	$ 7,800
Depreciation and amortization expense	$ 16,366	$ 14,188	$ 12,358

Goodwill and Intangible Asset_2

Goodwill and Intangible Assets - Changes in Carrying Amount of Goodwill (Details) - USD ($)	12 Months Ended
	Dec. 31, 2019	Dec. 31, 2018	Dec. 31, 2017
Goodwill [Roll Forward]
Beginning Balance	$ 95,031,000	$ 80,531,000
Acquisitions		14,606,000
Foreign exchange adjustments	(44,000)	(106,000)
Ending Balance	94,987,000	95,031,000	$ 80,531,000
Accumulated goodwill impairment charges	23,500,000
Goodwill impairment recognized	0	0	0
Business
Goodwill [Roll Forward]
Beginning Balance	87,007,000	72,507,000
Acquisitions		14,606,000
Foreign exchange adjustments	(44,000)	(106,000)
Ending Balance	86,963,000	87,007,000	72,507,000
Consumer
Goodwill [Roll Forward]
Beginning Balance	8,024,000	8,024,000
Foreign exchange adjustments	0	0
Ending Balance	$ 8,024,000	$ 8,024,000	$ 8,024,000

Goodwill and Intangible Asset_3

Goodwill and Intangible Assets - Summary of Intangible Assets (Details) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2019	Dec. 31, 2018
Acquired Finite-Lived Intangible Assets [Line Items]
Gross Carrying Amount	$ 50,906	$ 50,002
Accumulated Amortization	(39,094)	(36,170)
Net Carrying Amount	11,812	13,832
Technology
Acquired Finite-Lived Intangible Assets [Line Items]
Gross Carrying Amount	30,413	30,447
Accumulated Amortization	(25,187)	(23,615)
Net Carrying Amount	$ 5,226	$ 6,832
Weighted Average Amortization Period	5 years 3 months 18 days	5 years 3 months 18 days
Customer relationships
Acquired Finite-Lived Intangible Assets [Line Items]
Gross Carrying Amount	$ 16,964	$ 17,219
Accumulated Amortization	(12,958)	(11,786)
Net Carrying Amount	$ 4,006	$ 5,433
Weighted Average Amortization Period	8 years 4 months 24 days	8 years 4 months 24 days
Patents
Acquired Finite-Lived Intangible Assets [Line Items]
Gross Carrying Amount	$ 3,267	$ 2,074
Accumulated Amortization	(714)	(534)
Net Carrying Amount	$ 2,553	$ 1,540
Weighted Average Amortization Period	12 years 9 months 18 days	12 years 4 months 24 days
Other
Acquired Finite-Lived Intangible Assets [Line Items]
Gross Carrying Amount	$ 262	$ 262
Accumulated Amortization	(235)	(235)
Net Carrying Amount	$ 27	$ 27
Weighted Average Amortization Period	2 years 8 months 12 days	2 years 8 months 12 days

Goodwill and Intangible Asset_4

Goodwill and Intangible Assets - Summary of Amortization Expense (Details) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2019	Dec. 31, 2018	Dec. 31, 2017
Goodwill and Intangible Assets Disclosure [Abstract]
Aggregate amortization expense	$ 2,932	$ 2,813	$ 4,682
Estimated future amortization expense
2020	2,734
2021	2,520
2022	2,155
2023	904
2024	705
Thereafter	2,794
Total	$ 11,812	$ 13,832

Accrued Liabilities and Other_3

Accrued Liabilities and Other Current Liabilities (Details) - USD ($) $ in Thousands	Dec. 31, 2019	Dec. 31, 2018	Dec. 31, 2017
Payables and Accruals [Abstract]
Payroll and other employee related costs	$ 27,920	$ 19,014
Professional services, consulting and other vendor fees	20,382	17,461
Unrecognized tax benefits	2,053	1,913
Sales commissions	9,654	6,239
Contingent earn-out (Note 8)	557	2,372
Restructuring Reserve	314	977	$ 2,338
Other	1,898	2,686
Total	$ 62,778	$ 50,662

Convertible Senior Notes and _3

Convertible Senior Notes and Capped Call Transactions (Narrative) (Details) $ / shares in Units, shares in Thousands	1 Months Ended	12 Months Ended
	Mar. 31, 2019USD ($)equity_instrumentday$ / shares	Dec. 31, 2019USD ($)$ / sharesshares	Dec. 31, 2018$ / shares
Debt Instrument [Line Items]
Common stock, par value (in dollars per share) | $ / shares		$ 0.001	$ 0.001
Carry amount of equity component of convertible notes		$ 52,900,000
Total deferred issuance costs		8,600,000
Debt issuance costs attributable to liability		6,600,000
Adjustments to additional paid in capital related to issuance costs attributable to equity component		$ 1,986,000
Remaining amortization period for debt discount and debt issuance costs		4 years 2 months 12 days
Effective interest rate (percent)		5.88%
Number of shares of common stock covered by called caps (shares) | shares		5,960
Reduction to additional paid-in-capital related to called caps		$ 23,184,000
Capped Calls
Debt Instrument [Line Items]
Capped caps initial strike price (in dollars per share) | $ / shares		$ 38.58
Capped caps initial cap price (in dollars per share) | $ / shares		$ 57.16
Convertible Debt | Convertible Senior Notes
Debt Instrument [Line Items]
Aggregate principal	$ 230,000,000
Debt instrument stated rate (percent)	0.75%
Aggregate principal from exercise in full of over-allotment options	$ 30,000,000
Proceeds from debt offering, net of debt issuance costs	221,400,000
Debt instrument, unit of principal for conversion	$ 1,000
Number of shares per convertible note | equity_instrument	25.9182
Common stock, par value (in dollars per share) | $ / shares	$ 0.001
Convertible debt conversion price (in dollars per share) | $ / shares	$ 38.58
Percentage of principal amount paid if repurchase due to fundamental change (percent)	100.00%
Threshold trading days in consideration of note conversion | day	20
Threshold consecutive trading days in analysis of conversion price | day	30
Threshold percentage of stock price if converted	130.00%
Threshold for five day period, product of sale price of common stock and conversion rate of notes	98.00%
Carry amount of equity component of convertible notes		$ 52,900,000
Interest expense		9,999,000
Additional Paid-in Capital
Debt Instrument [Line Items]
Adjustments to additional paid in capital related to issuance costs attributable to equity component		1,986,000
Reduction to additional paid-in-capital related to called caps		23,184,000
Other expense, ent
Debt Instrument [Line Items]
Interest expense		$ 10,000,000

Convertible Senior Notes and _4

Convertible Senior Notes and Capped Call Transactions (Carrying Amount and Interest Expense) (Details) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2019	Dec. 31, 2018	Dec. 31, 2017
Carrying Amount of Equity Component:
Proceeds allocated to the conversion options (debt discount)	$ 52,900
Interest Expense:
Amortization of issuance costs	956	$ 0	$ 0
Amortization of debt discount	7,605	$ 0	$ 0
Convertible Debt | Convertible Senior Notes
Carrying Amount of Liability Component:
Principal	230,000
Unamortized discount	(45,295)
Unamortized issuance costs	(5,693)
Net carrying amount	179,012
Carrying Amount of Equity Component:
Proceeds allocated to the conversion options (debt discount)	52,900
Issuance costs	(1,986)
Net carrying amount	50,914
Interest Expense:
Contractual interest expense	1,438
Amortization of issuance costs	956
Amortization of debt discount	7,605
Total interest expense	$ 9,999

Acquisitions - Narrative (Detai

Acquisitions - Narrative (Details) - USD ($) $ in Thousands	1 Months Ended			12 Months Ended
	Oct. 31, 2018	Sep. 30, 2018	Jan. 31, 2018	Dec. 31, 2019	Dec. 31, 2018	Dec. 31, 2017
Business Acquisition [Line Items]
Payment related to contingent consideration				$ 487	$ 0	$ 0
Goodwill acquired in acquisition					14,606
Intangible assets acquired				50,906	$ 50,002
AdvantageTec
Business Acquisition [Line Items]
Aggregate purchase price	$ 11,200
Cash payment in acquisition	6,000
Equity consideration in acquisition	4,300
Potential earn-out consideration payments based on achieving targets	900			400
Goodwill acquired in acquisition	9,100
Intangible assets acquired	$ 2,200
Conversable Inc
Business Acquisition [Line Items]
Aggregate purchase price		$ 5,700
Cash payment in acquisition		1,300
Equity consideration in acquisition		2,900
Potential earn-out consideration payments based on achieving targets		1,500
Goodwill acquired in acquisition		5,500
Intangible assets acquired		500
Assets acquired liabilities assumed, net liability		$ (300)
BotCentral
Business Acquisition [Line Items]
Equity consideration in acquisition			$ 1,000
Business acquisition transaction costs			200
Intangible assets acquired			$ 200
Contingent earn-out
Business Acquisition [Line Items]
Payment related to contingent consideration				500
Contingent earn-out | AdvantageTec
Business Acquisition [Line Items]
Fair value adjustments				168
Contingent earn-out | Conversable Inc
Business Acquisition [Line Items]
Fair value adjustments				$ (496)

Fair Value Measurements - Narra

Fair Value Measurements - Narrative (Details) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2019	Dec. 31, 2018	Dec. 31, 2017
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Payment related to contingent consideration	$ 487	$ 0	$ 0
Conversable Inc and AdvantageTec
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Contingent earn-out		$ 2,400
Contingent earn-out
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Contingent earn-out decrease during the period	(1,800)
Payment related to contingent consideration	500
Equity issued as payment related to contingent consideration	1,000
Contingent earn-out | Conversable Inc
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Re-measurement to fair value increase (decrease)	(496)
Contingent earn-out | AdvantageTec
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Re-measurement to fair value increase (decrease)	168
Level 2 | Recurring | Convertible senior note
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Convertible senior note net	$ 194,300

Fair Value Measurements - Asset

Fair Value Measurements - Assets and Liabilities Measured at Fair Value (Details) - Recurring - USD ($) $ in Thousands	Dec. 31, 2019	Dec. 31, 2018
Assets:
Total assets	$ 2,899	$ 2,828
Liabilities:
Total liabilities	557	2,372
Money market funds
Assets:
Money market funds	2,899	2,828
Contingent earn-out
Liabilities:
Contingent earn-out	557	2,372
Level 1
Assets:
Total assets	2,899	2,828
Liabilities:
Total liabilities	0	0
Level 1 | Money market funds
Assets:
Money market funds	2,899	2,828
Level 1 | Contingent earn-out
Liabilities:
Contingent earn-out	0	0
Level 2
Assets:
Total assets	0	0
Liabilities:
Total liabilities	0	0
Level 2 | Money market funds
Assets:
Money market funds	0	0
Level 2 | Contingent earn-out
Liabilities:
Contingent earn-out	0	0
Level 3
Assets:
Total assets	0	0
Liabilities:
Total liabilities	557	2,372
Level 3 | Money market funds
Assets:
Money market funds	0	0
Level 3 | Contingent earn-out
Liabilities:
Contingent earn-out	$ 557	$ 2,372

Fair Value Measurements - Level

Fair Value Measurements - Level 3 Liabilities (Details) - Contingent earn-out - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2019	Dec. 31, 2018
Change in Fair Value of Level 3 Liability:
Balance, Beginning of year	$ 2,372	$ 0
Payments	(1,487)	0
Balance, End of year	557	2,372
Conversable Inc
Change in Fair Value of Level 3 Liability:
Additions		1,496
Fair value adjustments	(496)
AdvantageTec
Change in Fair Value of Level 3 Liability:
Additions		$ 876
Fair value adjustments	$ 168

Fair Value Measurements - Deriv

Fair Value Measurements - Derivative Financial Instruments (Details) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2019	Dec. 31, 2018	Dec. 31, 2017
Derivatives not designated as hedging instruments | Foreign currency derivative contracts | Other Income (Expense), net
Derivative [Line Items]
Gain (losses) on derivative instruments recognized in statements of operations	$ 0	$ (50)	$ 236

Commitments and Contingencies -

Commitments and Contingencies - Leases Narrative (Details) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2019	Dec. 31, 2018	Dec. 31, 2017
Lessee, Lease, Description [Line Items]
Operating lease right of use asset	$ 15,680
Operating lease liability	19,467
Lease expense for operating leases	13,000	$ 10,900	$ 9,900
Operating lease payments	$ 7,000
Minimum
Lessee, Lease, Description [Line Items]
Operating leases, initial lease terms	1 year
Maximum
Lessee, Lease, Description [Line Items]
Operating leases, initial lease terms	12 years

Commitments and Contingencies_2

Commitments and Contingencies - Lease Information (Details) $ in Thousands	Dec. 31, 2019USD ($)
Commitments and Contingencies Disclosure [Abstract]
Right-of-use asset, net	$ 15,680
Current operating lease liability	6,602
Long term operating lease liability	12,865
Total operating lease liability	$ 19,467
Operating leases, weighted average remaining lease term (in years)	3 years 6 months
Operating leases, weighted average discount rate (percent)	7.00%

Commitments and Contingencies_3

Commitments and Contingencies - Future Minimum Lease Payments Under Non-Cancelable Operating Leases (Details) $ in Thousands	Dec. 31, 2019USD ($)
Future Minimum Lease Payments
2020	$ 7,787
2021	6,530
2022	3,746
2023	1,925
2024	1,148
Thereafter	864
Total minimum lease payments	22,000
Less: present value adjustment	(2,533)
Total operating lease liability	$ 19,467

Commitments and Contingencies_4

Commitments and Contingencies - Employee Benefit Plans (Details) - USD ($)	9 Months Ended	12 Months Ended
	Sep. 30, 2018	Dec. 31, 2019	Dec. 31, 2018	Dec. 31, 2017
Other Commitments [Line Items]
Employer matching contribution, percent of match	50.00%
Employer matching contribution percent of eligible compensation	5.00%
Employer contribution limit	$ 6,000
Employer contribution vesting period	5 years
Employer matching contributions		$ 3,200,000	$ 1,600,000	$ 1,400,000
Match Step One
Other Commitments [Line Items]
Employer matching contribution, percent of match		100.00%
Employer matching contribution percent of eligible compensation		3.00%
Match Step Two
Other Commitments [Line Items]
Employer matching contribution, percent of match		50.00%
Employer matching contribution percent of eligible compensation		2.00%

Stockholders' Equity - Narrativ

Stockholders' Equity - Narrative (Details) - USD ($) $ / shares in Units, $ in Thousands	Apr. 11, 2019	Feb. 13, 2019	Oct. 29, 2018	Jul. 31, 2018	Apr. 25, 2018	Jun. 02, 2017	Apr. 30, 2017	Jun. 07, 2012	Nov. 30, 2019	Dec. 31, 2019	Sep. 30, 2019	Dec. 31, 2019	Dec. 31, 2018	Dec. 31, 2017	Dec. 31, 2009	Dec. 31, 2000	Jan. 31, 2018	Jun. 30, 2010	Dec. 31, 1998
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Increase in common stock authorized (in shares)									100,000,000
Common stock, shares authorized (in shares)										200,000,000		200,000,000	100,000,000
Common stock, shares issued (in shares)										66,543,073		66,543,073	63,676,229
Common stock, shares outstanding (in shares)										63,833,243		63,833,243	60,994,944
Common stock, par value (in dollars per share)										$ 0.001		$ 0.001	$ 0.001
Preferred stock, shares authorized (in shares)										5,000,000		5,000,000	5,000,000
Preferred stock, shares issued (in shares)										0		0	0
Preferred stock, shares outstanding (in shares)										0		0	0
Preferred stock, par value (in dollars per share)										$ 0.001		$ 0.001	$ 0.001
Weighted average fair value of stock options granted (in dollars per share)												$ 12.12	$ 6.60	$ 4.25
Dividend yield												0.00%	0.00%	0.00%
Expected life (in years)												5 years	5 years	5 years
Volatility determination period (in years)												5 years
Fair value of stock options exercised												$ 8,000	$ 16,100
Stock-based compensation expense												44,105	$ 14,841	$ 8,944
Accrual for cash awards to be settled in shares										$ 19,000		$ 19,000
2010 Employee Stock Purchase Plan
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Shares of common stock authorized and reserved for issuance (in shares)																		1,000,000
Amended and Restated 2010 Employee Stock Purchase Plan
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Shares of common stock authorized and reserved for issuance (in shares)						2,000,000
Increase in number of shares of common stock available for issuance (in shares)						1,000,000
2019 Employee Stock Purchase Plan
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Increase in number of shares of common stock available for issuance (in shares)										1,000,000
Shares of common stock available for issuance (in shares)										900,000		900,000
2018 Plan
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Shares of common stock authorized and reserved for issuance (in shares)										3,368,048		3,368,048					1,500,000
Increase in number of shares of common stock available for issuance (in shares)		618,048	250,000	500,000	500,000
Shares of common stock available for issuance (in shares)										800,000		800,000
Stock Option
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Unrecognized compensation cost										$ 22,700		$ 22,700
Weighted average recognition period of unrecognized compensation cost												2 years 4 months 24 days
Stock Option | 1998 Plan
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Shares of common stock authorized and reserved for issuance (in shares)																			5,850,000
Stock Option | 2000 Plan
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Shares of common stock authorized and reserved for issuance (in shares)																10,000,000
Increase in number of shares of common stock available for issuance (in shares)																4,150,000
Stock Option | 2009 Plan
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Increase in number of shares of common stock available for issuance (in shares)															6,000,000
Stock Option | 2009 Amended Plan
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Shares of common stock authorized and reserved for issuance (in shares)	32,067,744
Increase in number of shares of common stock available for issuance (in shares)	4,250,000						4,000,000	4,250,000
Stock option term (in years)											10 years
Shares of common stock available for issuance (in shares)										4,100,000		4,100,000
Restricted Stock Units (RSUs)
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Unrecognized compensation cost										$ 76,200		$ 76,200
Weighted average recognition period of unrecognized compensation cost												2 years 9 months 18 days
Restricted Stock Units (RSUs) | Minimum
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Vesting period (in years)												3 years
Restricted Stock Units (RSUs) | Maximum
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Vesting period (in years)												4 years

Stockholders' Equity - Weighted

Stockholders' Equity - Weighted Average Assumptions of Fair Value Options Using Black-Scholes Option-Pricing Model (Details)	12 Months Ended
	Dec. 31, 2019	Dec. 31, 2018	Dec. 31, 2017
Equity [Abstract]
Dividend yield	0.00%	0.00%	0.00%
Risk-free interest rate, minimum	1.66%	2.50%	1.70%
Risk-free interest rate, maximum	3.05%	3.10%	2.10%
Expected life (in years)	5 years	5 years	5 years
Historical volatility, minimum	43.42%	43.50%	46.60%
Historical volatility, maximum	44.00%	48.40%	48.10%

Stockholders' Equity - Summary

Stockholders' Equity - Summary of Stock Option Activity and Weighted Average Exercise Prices (Details) - USD ($) $ / shares in Units, shares in Thousands, $ in Thousands	12 Months Ended
	Dec. 31, 2019	Dec. 31, 2018	Dec. 31, 2017
Options
Options outstanding, beginning balance (in shares)	6,266	7,959	7,769
Granted (in shares)	1,425	2,033	2,042
Exercised (in shares)	(1,523)	(3,120)	(854)
Cancelled or expired (in shares)	(369)	(606)	(998)
Options outstanding, ending balance (in shares)	5,799	6,266	7,959
Options vested and expected to vest	5,096	5,550	7,163
Options exercisable	2,901	3,278	5,163
Weighted Average Exercise Price
Options outstanding, beginning balance (in dollars per share)	$ 12.13	$ 10.71	$ 10.88
Granted (in dollars per share)	29.76	15	9.87
Exercised (in dollars per share)	11.12	10.70	8.80
Cancelled (in dollars per share)	14.76	10.03	11.98
Options outstanding, ending balance (in dollars per share)	16.57	12.13	10.71
Options vested and expected to vest (in dollars per share)	15.29	11.89	10.75
Options exercisable (in dollars per share)	$ 12.03	$ 11.12	$ 11.17
Weighted Average Remaining Contractual Term (in years)
Options outstanding	6 years 9 months 14 days	6 years 6 months 18 days	5 years 10 months 6 days
Options vested and expected to vest	6 years 5 months 26 days	6 years 3 months 10 days	5 years 5 months 26 days
Options exercisable	4 years 11 months 12 days	4 years 7 months 20 days	4 years 6 months
Aggregate Intrinsic Value
Options outstanding	$ 119,064	$ 43,348	$ 14,881
Options vested and expected to vest	110,934	39,521	13,197
Options exercisable	$ 72,424	$ 25,367	$ 8,648

Stockholders' Equity - Summar_2

Stockholders' Equity - Summary of Outstanding and Vested Options (Details) shares in Thousands	12 Months Ended
	Dec. 31, 2019$ / sharesshares
Share-based Payment Arrangement, Option, Exercise Price Range [Line Items]
Options Outstanding, Number of Shares Outstanding | shares	5,799
Options Outstanding, Weighted-Average Remaining Contractual Life (Years)	6 years 9 months 14 days
Options Outstanding, Weighted-Average Exercise Price (in dollars per share)	$ 16.57
Options Exercisable, Number of Shares | shares	2,901
Options Exercisable, Weighted-Average Exercise Price (in dollars per share)	$ 12.03
$6.23 - $7.6
Share-based Payment Arrangement, Option, Exercise Price Range [Line Items]
Exercise price range, minimum (in dollars per share)	6.23
Exercise price range, maximum (in dollars per share)	$ 7.60000
Options Outstanding, Number of Shares Outstanding | shares	643
Options Outstanding, Weighted-Average Remaining Contractual Life (Years)	6 years 4 months 13 days
Options Outstanding, Weighted-Average Exercise Price (in dollars per share)	$ 7.42
Options Exercisable, Number of Shares | shares	392
Options Exercisable, Weighted-Average Exercise Price (in dollars per share)	$ 7.40
$7.95 - $10.05
Share-based Payment Arrangement, Option, Exercise Price Range [Line Items]
Exercise price range, minimum (in dollars per share)	7.95000
Exercise price range, maximum (in dollars per share)	$ 10.05
Options Outstanding, Number of Shares Outstanding | shares	648
Options Outstanding, Weighted-Average Remaining Contractual Life (Years)	4 years 9 months 29 days
Options Outstanding, Weighted-Average Exercise Price (in dollars per share)	$ 9.47
Options Exercisable, Number of Shares | shares	604
Options Exercisable, Weighted-Average Exercise Price (in dollars per share)	$ 9.48
$10.13 - $11.95
Share-based Payment Arrangement, Option, Exercise Price Range [Line Items]
Exercise price range, minimum (in dollars per share)	10.13
Exercise price range, maximum (in dollars per share)	$ 11.95
Options Outstanding, Number of Shares Outstanding | shares	621
Options Outstanding, Weighted-Average Remaining Contractual Life (Years)	5 years 11 months 4 days
Options Outstanding, Weighted-Average Exercise Price (in dollars per share)	$ 10.85
Options Exercisable, Number of Shares | shares	476
Options Exercisable, Weighted-Average Exercise Price (in dollars per share)	$ 10.53
$11.96 - $12.32
Share-based Payment Arrangement, Option, Exercise Price Range [Line Items]
Exercise price range, minimum (in dollars per share)	11.96
Exercise price range, maximum (in dollars per share)	$ 12.32
Options Outstanding, Number of Shares Outstanding | shares	50
Options Outstanding, Weighted-Average Remaining Contractual Life (Years)	1 year 6 months 3 days
Options Outstanding, Weighted-Average Exercise Price (in dollars per share)	$ 12.10
Options Exercisable, Number of Shares | shares	50
Options Exercisable, Weighted-Average Exercise Price (in dollars per share)	$ 12.10
$12.45 - $12.45
Share-based Payment Arrangement, Option, Exercise Price Range [Line Items]
Exercise price range, minimum (in dollars per share)	12.45
Exercise price range, maximum (in dollars per share)	$ 12.45
Options Outstanding, Number of Shares Outstanding | shares	782
Options Outstanding, Weighted-Average Remaining Contractual Life (Years)	7 years 10 months 28 days
Options Outstanding, Weighted-Average Exercise Price (in dollars per share)	$ 12.45
Options Exercisable, Number of Shares | shares	287
Options Exercisable, Weighted-Average Exercise Price (in dollars per share)	$ 12.45
$12.46 - $14.3
Share-based Payment Arrangement, Option, Exercise Price Range [Line Items]
Exercise price range, minimum (in dollars per share)	12.46
Exercise price range, maximum (in dollars per share)	$ 14.3
Options Outstanding, Number of Shares Outstanding | shares	758
Options Outstanding, Weighted-Average Remaining Contractual Life (Years)	3 years 7 months 13 days
Options Outstanding, Weighted-Average Exercise Price (in dollars per share)	$ 13.57
Options Exercisable, Number of Shares | shares	628
Options Exercisable, Weighted-Average Exercise Price (in dollars per share)	$ 13.41
$14.5 - $17.88
Share-based Payment Arrangement, Option, Exercise Price Range [Line Items]
Exercise price range, minimum (in dollars per share)	14.50
Exercise price range, maximum (in dollars per share)	$ 17.88
Options Outstanding, Number of Shares Outstanding | shares	580
Options Outstanding, Weighted-Average Remaining Contractual Life (Years)	6 years 5 months 8 days
Options Outstanding, Weighted-Average Exercise Price (in dollars per share)	$ 16.11
Options Exercisable, Number of Shares | shares	271
Options Exercisable, Weighted-Average Exercise Price (in dollars per share)	$ 16.60
$18.09 - $28.18
Share-based Payment Arrangement, Option, Exercise Price Range [Line Items]
Exercise price range, minimum (in dollars per share)	18.09
Exercise price range, maximum (in dollars per share)	$ 28.18
Options Outstanding, Number of Shares Outstanding | shares	803
Options Outstanding, Weighted-Average Remaining Contractual Life (Years)	8 years 10 months 20 days
Options Outstanding, Weighted-Average Exercise Price (in dollars per share)	$ 24.15
Options Exercisable, Number of Shares | shares	193
Options Exercisable, Weighted-Average Exercise Price (in dollars per share)	$ 21.55
$28.23 - $32.37
Share-based Payment Arrangement, Option, Exercise Price Range [Line Items]
Exercise price range, minimum (in dollars per share)	28.23
Exercise price range, maximum (in dollars per share)	$ 32.37
Options Outstanding, Number of Shares Outstanding | shares	756
Options Outstanding, Weighted-Average Remaining Contractual Life (Years)	9 years 4 months 17 days
Options Outstanding, Weighted-Average Exercise Price (in dollars per share)	$ 29.93
Options Exercisable, Number of Shares | shares	0
Options Exercisable, Weighted-Average Exercise Price (in dollars per share)	$ 0
$40.61 - $40.61
Share-based Payment Arrangement, Option, Exercise Price Range [Line Items]
Exercise price range, minimum (in dollars per share)	40.61
Exercise price range, maximum (in dollars per share)	$ 40.61
Options Outstanding, Number of Shares Outstanding | shares	158
Options Outstanding, Weighted-Average Remaining Contractual Life (Years)	9 years 5 months 19 days
Options Outstanding, Weighted-Average Exercise Price (in dollars per share)	$ 40.61
Options Exercisable, Number of Shares | shares	0
Options Exercisable, Weighted-Average Exercise Price (in dollars per share)	$ 0

Stockholders' Equity - Summar_3

Stockholders' Equity - Summary of Restricted Stock Unit Activity (Details) - Restricted Stock Units (RSUs) - USD ($) $ / shares in Units, shares in Thousands, $ in Thousands	12 Months Ended
	Dec. 31, 2019	Dec. 31, 2018	Dec. 31, 2017	Dec. 31, 2016
Share-based Compensation Arrangement by Share-based Payment Award, Equity Instruments Other than Options, Nonvested, Number of Shares [Roll Forward]
Balance outstanding, beginning (shares)	2,690	873	1,188
Awarded (shares)	1,979	2,568	332
Released (shares)	(1,197)	(361)	(363)
Forfeited (shares)	(423)	(390)	(284)
Non-vested and outstanding, ending (shares)	3,049	2,690	873
Expected to vest (shares)	2,059
Weighted Average Grant Date Fair Value (Per Share)
Balance outstanding, beginning (in dollars per share)	$ 15.81	$ 8.29	$ 8.44
Awarded (in dollars per share)	30.99	17.02	8.16
Released (in dollars per share)	14.24	9.49	8.48
Forfeited (in dollars per share)	20.28	9.49	8.46
Non-vested and outstanding, ending (in dollars per share)	24.73	$ 15.81	$ 8.29
Expected to vest (in dollars per share)	$ 22.97
Aggregate Fair Value
Non-vested and outstanding	$ 112,848	$ 50,756	$ 10,053	$ 8,968
Expected to vest	$ 76,185

Income Taxes - Narrative (Detai

Income Taxes - Narrative (Details) - USD ($) $ in Thousands	3 Months Ended	12 Months Ended
	Dec. 31, 2017	Dec. 31, 2019	Dec. 31, 2018	Dec. 31, 2017
Operating Loss Carryforwards [Line Items]
Valuation recorded		$ 19,100
Unrecognized tax benefits	$ 4,924	2,053	$ 1,921	$ 4,924
Decrease due to expiration of statue		452	445
Decrease in federal deferred tax provision upon remeasurement of net deferred taxes at newly enacted rate, provisional estimate	10,100
Federal deferred tax benefit upon remeasurement of valuation allowance at newly enacted rate, provisional estimate	12,600
Federal deferred tax benefit for indefinite lived deferred tax liabilities, provisional estimate	$ 2,000
Percentage of indefinite-lived deferred tax liabilities (percent)	80.00%
State deferred tax provision	$ 1,200	135	$ (28)	(1,144)
Federal
Operating Loss Carryforwards [Line Items]
Operating loss carryforwards		203,500
Operating loss carryforwards generated in taxable years ending on or before December 31 2017	$ 32,800	41,200		$ 32,800
Net operating loss carryforwards, not subject to expiration		162,300
Operating loss carryforwards, period of carryforward (in years)				20 years
Federal | Expiration between 2023 and 2026
Operating Loss Carryforwards [Line Items]
Net operating loss carryforwards, subject to expiration		6,000
Federal | Expiration between 2036 and 2037
Operating Loss Carryforwards [Line Items]
Net operating loss carryforwards, subject to expiration		34,900
Federal | Proficient
Operating Loss Carryforwards [Line Items]
Operating loss carryforwards		5,100
Foreign | Australian Taxation Office
Operating Loss Carryforwards [Line Items]
Operating loss carryforwards		$ 5,300

Income Taxes - Domestic and For

Income Taxes - Domestic and Foreign Components of Income Before Provision for Income Taxes (Details) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2019	Dec. 31, 2018	Dec. 31, 2017
Income Tax Contingency [Line Items]
United States	$ (105,961)	$ (38,078)	$ (25,585)
(Loss) income before provision for (benefit from) income taxes	(93,226)	(24,174)	(17,690)
Israel
Income Tax Contingency [Line Items]
Foreign	2,791	3,163	3,458
United Kingdom
Income Tax Contingency [Line Items]
Foreign	5,377	3,690	2,087
Netherlands
Income Tax Contingency [Line Items]
Foreign	(465)	3,235	1,568
Australia
Income Tax Contingency [Line Items]
Foreign	716	686	(1,979)
Germany [Member]
Income Tax Contingency [Line Items]
Foreign	3,854	2,900	2,424
Japan [Member]
Income Tax Contingency [Line Items]
Foreign	$ 462	$ 230	$ 337

Income Taxes - Schedule of Prov

Income Taxes - Schedule of Provision for Income Taxes (Details) - USD ($) $ in Thousands	3 Months Ended	12 Months Ended
	Dec. 31, 2017	Dec. 31, 2019	Dec. 31, 2018	Dec. 31, 2017
Current income taxes:
Current income taxes, U.S. Federal		$ (452)	$ (1,932)	$ 0
Current income taxes, State and local		89	67	47
Current income taxes, Foreign		4,415	3,032	2,852
Total current income taxes		4,052	1,167	2,899
Deferred income taxes:
Deferred income taxes, U.S. Federal		126	(295)	(1,289)
Deferred income taxes, State and local	$ 1,200	135	(28)	(1,144)
Deferred income taxes, Foreign		(1,468)	14	35
Total deferred income taxes		(1,207)	(309)	(2,398)
Total income taxes		$ 2,845	$ 858	$ 501

Income Taxes - Schedule of Reco

Income Taxes - Schedule of Reconciliations of Federal Statutory Tax Rate to Effective Income Tax Rate (Details)	12 Months Ended
	Dec. 31, 2019	Dec. 31, 2018	Dec. 31, 2017
Income Tax Disclosure [Abstract]
Federal statutory rate	21.00%	21.00%	34.00%
State taxes, net of federal benefit	2.95%	3.30%	4.09%
Non-deductible expenses – stock based compensation	1.82%	4.73%	(0.78%)
Global Intangible Low Tax Income Inclusion	(2.29%)	(7.99%)	0.00%
Non-deductible expenses – Other	(1.57%)	(2.58%)	(1.19%)
Foreign taxes	(1.86%)	(1.34%)	(1.97%)
Valuation allowance	(26.42%)	(28.91%)	26.12%
Stock based compensation - excess tax benefit	6.18%	6.10%	0.00%
Effect of new tax legislation	0	0	(0.5684)
Other	(2.86%)	2.09%	(6.26%)
Total provision	(3.05%)	(3.60%)	(2.83%)

Income Taxes - Schedule of Fede

Income Taxes - Schedule of Federal Deferred Tax Assets and Deferred Tax Liabilities (Details) - USD ($) $ in Thousands	Dec. 31, 2019	Dec. 31, 2018
Deferred tax assets:
Net operating loss carryforwards	$ 49,423	$ 18,083
Original Issue Discount	5,201	0
Interest	875	0
Operating lease liability	3,306	0
Accounts payable and accrued expenses	5,934	4,024
Non-cash compensation	4,195	9,597
Intangibles amortization	3,273	5,691
Allowance for doubtful accounts	419	315
Total deferred tax assets	72,626	37,710
Less valuation allowance	(48,451)	(30,185)
Deferred tax assets, net of valuation allowance	24,175	7,525
Deferred tax liabilities:
Property and equipment	(6,361)	(3,736)
Goodwill amortization and contingent earn-out adjustments	(3,430)	(4,172)
Convertible Notes Issuance	(11,055)	0
Operating lease right of use asset	(2,504)	0
Total deferred tax liabilities	(23,350)	(7,908)
Net deferred tax assets (liabilities)	$ 825
Net deferred tax assets (liabilities)		$ (383)

Income Taxes - Schedule of Unre

Income Taxes - Schedule of Unrecognized Tax Benefits (Details) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2019	Dec. 31, 2018
Reconciliation of Unrecognized Tax Benefits, Excluding Amounts Pertaining to Examined Tax Returns [Roll Forward]
Unrecognized tax benefits balance at January 1	$ 1,921	$ 4,924
Gross increase for tax positions of prior years	0	0
Gross increase for tax positions of current years	584	405
Decrease due to expiration of statue	(452)	(445)
Decrease due to settlement	0	(2,963)
Gross unrecognized tax benefits at December 31	$ 2,053	$ 1,921

Restructuring Costs - Narrative

Restructuring Costs - Narrative (Details) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2019	Dec. 31, 2018	Dec. 31, 2017
Restructuring and Related Activities [Abstract]
Restructuring charges	$ 2,043	$ 4,468	$ 2,594
Restructuring liability	$ 314	$ 977	$ 2,338

Restructuring Costs - Component

Restructuring Costs - Components of Restructuring Charges (Details) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2019	Dec. 31, 2018
Restructuring Reserve [Roll Forward]
Balance, Beginning of the year	$ 977	$ 2,338
Severance and other associated costs	2,043	4,468
Cash payments	(2,706)	(5,829)
Balance, End of year	$ 314	$ 977

Restructuring Costs - Expenses

Restructuring Costs - Expenses Related to Restructuring Charges (Details) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2019	Dec. 31, 2018	Dec. 31, 2017
Restructuring Cost and Reserve [Line Items]
Restructuring charges	$ 2,043	$ 4,468	$ 2,594
Severance and other associated costs
Restructuring Cost and Reserve [Line Items]
Restructuring charges	2,043	4,468	648
Wind down costs of legacy platform
Restructuring Cost and Reserve [Line Items]
Restructuring charges	$ 0	$ 0	$ 1,946