Description of Business and Basis of Presentation	9 Months Ended
Sep. 30, 2017
Accounting Policies [Abstract]
Description of Business and Basis of Presentation	Description of Business and Basis of Presentation LivePerson, Inc. (the “Company” or “LivePerson”) 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) and international offices in Amsterdam, Berlin, London, Mannheim, Melbourne, Milan, Paris, Ra'anana (Israel), Reading (UK), and Tokyo. LivePerson provides mobile and online business messaging solutions that power digital communication between brands and consumers. LiveEngage, the Company’s enterprise-class, cloud-based platform, enables businesses to create a meaningful connection with consumers via messaging. As consumers have reoriented their digital lives around the smartphone, messaging apps have become their preferred communication channel to connect with each other. LivePerson allows brands to align with this new consumer preference by deploying messaging at scale for customer care and sales as an alternative to email or to calling a contact center. LiveEngage is designed to securely deploy messaging at scale for brands with tens of millions of customers and many thousands of customer care agents. Key benefits include a sophisticated proactive targeting engine and a robust suite of text and mobile messaging, real-time chat messaging, content delivery, customer sentiment, and cobrowsing offerings that power intelligent digital engagement with consumers. LiveEngage powers conversations across each of a brand’s primary digital channels, including mobile apps, mobile and desktop web browsers, social media and third-party consumer messaging platforms. LivePerson optimizes campaign outcomes for sales and service transactions by combining website visitor data with other historical, behavioral, and operational information to develop insights into each step of a consumer’s journey. LivePerson’s products, coupled with its domain knowledge, industry expertise and consulting services, have been proven to maximize the effectiveness of consumer engagement. The Company’s primary revenue source is from the sale of LivePerson services to businesses of all sizes. The Company also offers 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”). Basis of Presentation The accompanying condensed consolidated financial statements as of September 30, 2017 and for the three and nine months ended September 30, 2017 and 2016 are unaudited. In the opinion of management, the unaudited condensed consolidated financial statements have been prepared on the same basis as the annual financial statements and reflect all adjustments, which include only normal recurring adjustments, necessary to present fairly the consolidated financial position of LivePerson as of September 30, 2017, and the consolidated results of operations, comprehensive loss and cash flows for the interim periods ended September 30, 2017 and 2016. The financial data and other information disclosed in these notes to the condensed consolidated financial statements related to these periods are unaudited. The results of operations for any interim period are not necessarily indicative of the results of operations for any other future interim period or for a full fiscal year. The condensed consolidated balance sheet at December 31, 2016 has been derived from audited consolidated financial statements at that date. Certain information and note disclosures normally included in financial statements prepared in accordance with generally accepted accounting principles in the United States (“GAAP”) have been condensed or omitted pursuant to the rules and regulations of the Securities and Exchange Commission (the “SEC”). These unaudited interim condensed consolidated financial statements should be read in conjunction with the Company’s audited consolidated financial statements and notes thereto for the year ended December 31, 2016 included in the Company’s Annual Report on Form 10-K filed with the SEC on March 10, 2017. Principles of Consolidation The condensed consolidated financial statements include the Company and its wholly-owned subsidiaries. All intercompany balances and transactions have been eliminated. Use of Estimates The preparation of the Company’s condensed consolidated financial statements in conformity with GAAP requires management to make estimates and assumptions that affect the reported amounts of assets and liabilities and disclosure of contingent assets and liabilities at the date of the condensed consolidated financial statements and the reported amounts of income and expenses during the reporting period. These estimates are based on information available as of the date of the condensed consolidated financial statements; therefore, actual results could differ from management’s estimates. Recently Issued Accounting Standards In August 2017, the Financial Accounting Standards Board (“FASB”) issued Accounting Standards Update No. 2017-12 "Derivatives and Hedging (Topic 815): Targeted Improvements to Accounting for Hedging Activities" ("ASU 2017-12"). This new standard refines and expands hedge accounting for both financial (e.g., interest rate) and commodity risks. Its provisions create more transparency around how economic results are presented, both on the face of the financial statements and in the footnotes, for investors and analysts. ASU 2017-12 is effective for fiscal years, and interim periods within those fiscal years, beginning after December 15, 2018, for public companies. Early adoption is permitted in any interim period or fiscal years before the effective date of the standard. The Company does not expect the adoption of ASU 2017-12 to have a material effect on its financial position, results of operations or cash flows. In May 2017, FASB issued Accounting Standards Update No. 2017-09, "Compensation-Stock Compensation (Topic 718): Scope of Modification Accounting" (“ASU 2017-09”). This update clarifies and reduces both (i) diversity in practice and (ii) cost and complexity when applying the guidance in Topic 718, to a change to the terms and conditions of a share-based payment award. ASU 2017-09 is effective for financial statements issued for annual periods, and interim periods within those annual periods, beginning after December 15, 2017. Early adoption is permitted. The amendments in this ASU should be applied prospectively to an award modified on or after the adoption date. The Company is currently evaluating the impact of this updated standard, but does not believe this update will have a significant impact on its consolidated financial statements. In January 2017, FASB issued Accounting Standards Update 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 to have a material effect on its financial position, results of operations or cash flows. In January 2017, the FASB issued Accounting Standards Update No. 2017-01, "Business Combinations (Topic 805): Clarifying the Definition of a Business" (“ASU 2017-01”). This update clarifies the definition of a business with the objective of adding guidance to assist entities with evaluating whether transactions should be accounted for as acquisitions (or disposals) of businesses. The amendments in this update provide a screen to determine when a set is not a business. If the screen is not met, it (1) requires that to be considered a business, a set must include, at a minimum, an input and a substantive process that together significantly contribute to the ability to create output and (2) removes the evaluation of whether a market participant could replace the missing elements. ASU 2017-01 is effective for financial statements issued for annual periods beginning after December 15, 2017, and interim periods within those annual periods. The Company does not expect the adoption of ASU 2017-01 to have a material effect on its financial position, results of operations or cash flows. In March 2016, the FASB issued Accounting Standards Update No. 2016-09, “Compensation -Stock Compensation (Topic 718): Improvements to Employee Share-Based Payment Accounting” (“ASU 2016-09”). This update is intended to improve the accounting for employee share-based payments and affects all organizations that issue share-based payment awards to their employees. Several aspects of the accounting for share-based payment award transactions are simplified, including:(a) income tax consequences; (b) classification of awards as either equity or liabilities; and (c) classification on the statement of cash flows. The Company adopted this ASU as of the beginning of the first quarter of 2017 and has elected to continue to estimate expected forfeitures over the course of a vesting period. Further, the ASU eliminates the requirement to delay the recognition of excess tax benefits until they reduce current taxes payable. The adoption of ASU 2016-09 did not have any material impact on the Company’s financial statements. In February 2016, the FASB issued Accounting Standards Update 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. Certain targeted improvements were made to align, where necessary, lessor accounting with the lessee accounting model and Topic 606, “Revenue from Contracts with Customers”. The new lease guidance also simplified the accounting for sale and leaseback transactions primarily because lessees must recognize lease assets and lease liabilities. Lessees will no longer be provided with a source of off-balance sheet financing. Lessees (for capital and operating leases) and lessors (for sales-type, direct financing, and operating leases) must 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. Lessees and lessors may not apply a full retrospective transition approach. ASU 2016-02 is effective for financial statements issued for annual periods beginning after December 15, 2018. While the Company is currently assessing the impact ASU 2016-02 will have on the consolidated financial statements, the Company expects the primary impact to its consolidated financial position upon adoption will be the recognition, on a discounted basis, of its minimum commitments under non-cancelable operating leases on the consolidated balance sheets resulting in the recording of right of use assets and lease obligations. The Company is also currently evaluating the timing of adoption and the impact that the standard will have on its condensed consolidated financial statements and related disclosures. In May 2014, the FASB issued ASC Update No. 2014-09, Revenue from Contracts with Customers (“Topic 606”), which has been subsequently updated. The purpose of Update No. 2014-09 is to provide enhancements to the quality and consistency of how revenue is reported while also improving comparability in the financial statements of companies using U.S. GAAP and International Financial Reporting Standards. The core principle requires entities to recognize revenue in a manner that depicts the transfer of goods or services to customers in amounts that reflect the consideration an entity expects to be entitled to in exchange for those goods or services. Topic 606, as amended, becomes effective for annual periods beginning after December 15, 2017, at which point we plan to adopt the standard. The Company currently plans to adopt the standard using the “modified retrospective method.” Under that method, the Company will apply the rules to contracts that are not completed as of January 1, 2018, and recognize the cumulative effect of the initial adoption as an adjustment to the opening balance of retained earnings. The Company has reached preliminary conclusions on our key revenue streams related to the standard and are finalizing our accounting policies. Based on its initial assessment, the Company believes the timing of revenue recognition for its primary revenue stream, hosted services within its Business segment, will not materially change. Upon adopting Topic 606, the Company will provide additional disclosures in the notes to the consolidated financial statements, specifically related to disaggregated revenue, contract balances and performance obligations. In the third quarter of 2017, the Company provided global training to its finance team on Topic 606. In the fourth quarter of 2017, the Company will perform a simulation of its new accounting processes and procedures to prepare its team for the month-end close process upon adoption of Topic 606. The Company will implement new internal controls to address risks associated with applying the five-step model, specifically related to judgments made in connection to variable consideration and applying the constraint. Additionally, the Company will establish monitoring controls to identify new sales arrangements and changes in its business environment that could impact its current accounting assessment. The Company expects to finalize its impact assessment and redesign impacted processes, policies and controls during the fourth quarter of 2017.

Description of Business and Basis of Presentation

LivePerson, Inc. (the “Company” or “LivePerson”) 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) and international offices in Amsterdam, Berlin, London, Mannheim, Melbourne, Milan, Paris, Ra'anana (Israel), Reading (UK), and Tokyo.

LivePerson provides mobile and online business messaging solutions that power digital communication between brands and consumers. LiveEngage, the Company’s enterprise-class, cloud-based platform, enables businesses to create a meaningful connection with consumers via messaging. As consumers have reoriented their digital lives around the smartphone, messaging apps have become their preferred communication channel to connect with each other. LivePerson allows brands to align with this new consumer preference by deploying messaging at scale for customer care and sales as an alternative to email or to calling a contact center.

LiveEngage is designed to securely deploy messaging at scale for brands with tens of millions of customers and many thousands of customer care agents. Key benefits include a sophisticated proactive targeting engine and a robust suite of text and mobile messaging, real-time chat messaging, content delivery, customer sentiment, and cobrowsing offerings that power intelligent digital engagement with consumers. LiveEngage powers conversations across each of a brand’s primary digital channels, including mobile apps, mobile and desktop web browsers, social media and third-party consumer messaging platforms.

LivePerson optimizes campaign outcomes for sales and service transactions by combining website visitor data with other historical, behavioral, and operational information to develop insights into each step of a consumer’s journey. LivePerson’s products, coupled with its domain knowledge, industry expertise and consulting services, have been proven to maximize the effectiveness of consumer engagement.

The Company’s primary revenue source is from the sale of LivePerson services to businesses of all sizes. The Company also offers 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”).

Basis of Presentation

The accompanying condensed consolidated financial statements as of September 30, 2017 and for the three and nine months ended September 30, 2017 and 2016 are unaudited. In the opinion of management, the unaudited condensed consolidated financial statements have been prepared on the same basis as the annual financial statements and reflect all adjustments, which include only normal recurring adjustments, necessary to present fairly the consolidated financial position of LivePerson as of September 30, 2017, and the consolidated results of operations, comprehensive loss and cash flows for the interim periods ended September 30, 2017 and 2016. The financial data and other information disclosed in these notes to the condensed consolidated financial statements related to these periods are unaudited. The results of operations for any interim period are not necessarily indicative of the results of operations for any other future interim period or for a full fiscal year. The condensed consolidated balance sheet at December 31, 2016 has been derived from audited consolidated financial statements at that date.

Certain information and note disclosures normally included in financial statements prepared in accordance with generally accepted accounting principles in the United States (“GAAP”) have been condensed or omitted pursuant to the rules and regulations of the Securities and Exchange Commission (the “SEC”). These unaudited interim condensed consolidated financial statements should be read in conjunction with the Company’s audited consolidated financial statements and notes thereto for the year ended December 31, 2016 included in the Company’s Annual Report on Form 10-K filed with the SEC on March 10, 2017.

Principles of Consolidation

The condensed consolidated financial statements include the Company and its wholly-owned subsidiaries. All intercompany balances and transactions have been eliminated.

Use of Estimates

The preparation of the Company’s condensed consolidated financial statements in conformity with GAAP requires management to make estimates and assumptions that affect the reported amounts of assets and liabilities and disclosure of contingent assets and liabilities at the date of the condensed consolidated financial statements and the reported amounts of income and expenses during the reporting period. These estimates are based on information available as of the date of the condensed consolidated financial statements; therefore, actual results could differ from management’s estimates.

Recently Issued Accounting Standards

In August 2017, the Financial Accounting Standards Board (“FASB”) issued Accounting Standards Update No. 2017-12 "Derivatives and Hedging (Topic 815): Targeted Improvements to Accounting for Hedging Activities" ("ASU 2017-12"). This new standard refines and expands hedge accounting for both financial (e.g., interest rate) and commodity risks. Its provisions create more transparency around how economic results are presented, both on the face of the financial statements and in the footnotes, for investors and analysts. ASU 2017-12 is effective for fiscal years, and interim periods within those fiscal years, beginning after December 15, 2018, for public companies. Early adoption is permitted in any interim period or fiscal years before the effective date of the standard. The Company does not expect the adoption of ASU 2017-12 to have a material effect on its financial position, results of operations or cash flows.

In May 2017, FASB issued Accounting Standards Update No. 2017-09, "Compensation-Stock Compensation (Topic 718): Scope of Modification Accounting" (“ASU 2017-09”). This update clarifies and reduces both (i) diversity in practice and (ii) cost and complexity when applying the guidance in Topic 718, to a change to the terms and conditions of a share-based payment award. ASU 2017-09 is effective for financial statements issued for annual periods, and interim periods within those annual periods, beginning after December 15, 2017. Early adoption is permitted. The amendments in this ASU should be applied prospectively to an award modified on or after the adoption date. The Company is currently evaluating the impact of this updated standard, but does not believe this update will have a significant impact on its consolidated financial statements.

In January 2017, FASB issued Accounting Standards Update 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 to have a material effect on its financial position, results of operations or cash flows.

In January 2017, the FASB issued Accounting Standards Update No. 2017-01, "Business Combinations (Topic 805): Clarifying the Definition of a Business" (“ASU 2017-01”). This update clarifies the definition of a business with the objective of adding guidance to assist entities with evaluating whether transactions should be accounted for as acquisitions (or disposals) of businesses. The amendments in this update provide a screen to determine when a set is not a business. If the screen is not met, it (1) requires that to be considered a business, a set must include, at a minimum, an input and a substantive process that together significantly contribute to the ability to create output and (2) removes the evaluation of whether a market participant could replace the missing elements. ASU 2017-01 is effective for financial statements issued for annual periods beginning after December 15, 2017, and interim periods within those annual periods. The Company does not expect the adoption of ASU 2017-01 to have a material effect on its financial position, results of operations or cash flows.

In March 2016, the FASB issued Accounting Standards Update No. 2016-09, “Compensation -Stock Compensation (Topic 718): Improvements to Employee Share-Based Payment Accounting” (“ASU 2016-09”). This update is intended to improve the accounting for employee share-based payments and affects all organizations that issue share-based payment awards to their employees. Several aspects of the accounting for share-based payment award transactions are simplified, including:(a) income tax consequences; (b) classification of awards as either equity or liabilities; and (c) classification on the statement of cash flows. The Company adopted this ASU as of the beginning of the first quarter of 2017 and has elected to continue to estimate expected forfeitures over the course of a vesting period. Further, the ASU eliminates the requirement to delay the recognition of excess tax benefits until they reduce current taxes payable. The adoption of ASU 2016-09 did not have any material impact on the Company’s financial statements.

In February 2016, the FASB issued Accounting Standards Update 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. Certain targeted improvements were made to align, where necessary, lessor accounting with the lessee accounting model and Topic 606, “Revenue from Contracts with Customers”. The new lease guidance also simplified the accounting for sale and leaseback transactions primarily because lessees must recognize lease assets and lease liabilities. Lessees will no longer be provided with a source of off-balance sheet financing. Lessees (for capital and operating leases) and lessors (for sales-type, direct financing, and operating leases) must 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. Lessees and lessors may not apply a full retrospective transition approach. ASU 2016-02 is effective for financial statements issued for annual periods beginning after December 15, 2018. While the Company is currently assessing the impact ASU 2016-02 will have on the consolidated financial statements, the Company expects the primary impact to its consolidated financial position upon adoption will be the recognition, on a discounted basis, of its minimum commitments under non-cancelable operating leases on the consolidated balance sheets resulting in the recording of right of use assets and lease obligations. The Company is also currently evaluating the timing of adoption and the impact that the standard will have on its condensed consolidated financial statements and related disclosures.

In May 2014, the FASB issued ASC Update No. 2014-09, Revenue from Contracts with Customers (“Topic 606”), which has been subsequently updated. The purpose of Update No. 2014-09 is to provide enhancements to the quality and consistency of how revenue is reported while also improving comparability in the financial statements of companies using U.S. GAAP and International Financial Reporting Standards. The core principle requires entities to recognize revenue in a manner that depicts the transfer of goods or services to customers in amounts that reflect the consideration an entity expects to be entitled to in exchange for those goods or services. Topic 606, as amended, becomes effective for annual periods beginning after December 15, 2017, at which point we plan to adopt the standard. The Company currently plans to adopt the standard using the “modified retrospective method.” Under that method, the Company will apply the rules to contracts that are not completed as of January 1, 2018, and recognize the cumulative effect of the initial adoption as an adjustment to the opening balance of retained earnings.

The Company has reached preliminary conclusions on our key revenue streams related to the standard and are finalizing our accounting policies. Based on its initial assessment, the Company believes the timing of revenue recognition for its primary revenue stream, hosted services within its Business segment, will not materially change. Upon adopting Topic 606, the Company will provide additional disclosures in the notes to the consolidated financial statements, specifically related to disaggregated revenue, contract balances and performance obligations.

In the third quarter of 2017, the Company provided global training to its finance team on Topic 606. In the fourth quarter of 2017, the Company will perform a simulation of its new accounting processes and procedures to prepare its team for the month-end close process upon adoption of Topic 606. The Company will implement new internal controls to address risks associated with applying the five-step model, specifically related to judgments made in connection to variable consideration and applying the constraint. Additionally, the Company will establish monitoring controls to identify new sales arrangements and changes in its business environment that could impact its current accounting assessment. The Company expects to finalize its impact assessment and redesign impacted processes, policies and controls during the fourth quarter of 2017.