LivePerson (LPSN) 10-Q 11 May 15 2015 Q1 Quarterly report Financial data

Document_and_Entity_Informatio

Document and Entity Information	3 Months Ended
	Mar. 31, 2015	5-May-15
Document - Document And Entity Information [Abstract]
Document Type	10-Q
Amendment Flag	FALSE
Document Period End Date	31-Mar-15
Document Fiscal Year Focus	2015
Document Fiscal Period Focus	Q1
Trading Symbol	lpsn
Entity Registrant Name	LIVEPERSON INC
Entity Central Index Key	1102993
Current Fiscal Year End Date	-19
Entity Filer Category	Accelerated Filer
Entity Common Stock, Shares Outstanding		57,051,150

CONDENSED_CONSOLIDATED_BALANCE

CONDENSED CONSOLIDATED BALANCE SHEETS (USD $)	Mar. 31, 2015	Dec. 31, 2014
In Thousands, unless otherwise specified
CURRENT ASSETS:
Cash and cash equivalents	$40,836	$49,372
Accounts receivable, net of allowance for doubtful accounts of $1,360 and $1,275 as of March 31, 2015 and December 31, 2014, respectively	35,588	31,382
Prepaid expenses and other current assets	12,919	10,374
Deferred tax assets, net	1,236	2,575
Total current assets	90,579	93,703
Property and equipment, net	20,973	19,583
Intangibles, net	30,629	32,620
Goodwill	80,310	80,848
Deferred tax assets, net	11,281	10,762
Other assets	2,316	2,301
Total assets	236,088	239,817
CURRENT LIABILITIES:
Accounts payable	12,568	8,985
Accrued expenses and other current liabilities	31,531	37,772
Deferred revenue	10,216	11,992
Total current liabilities	54,315	58,749
Other liabilities	724	731
Total liabilities	55,039	59,480
Commitments and contingencies (See Note 10)
STOCKHOLDERS’ EQUITY (See Note 11):
Common stock	58	57
Additional paid-in capital	277,801	274,046
Treasury stock	-1	-1
Accumulated deficit	-94,682	-92,627
Accumulated other comprehensive loss	-2,127	-1,138
Total stockholders’ equity	181,049	180,337
Total liabilities and stockholders’ equity	$236,088	$239,817

CONDENSED_CONSOLIDATED_BALANCE1

CONDENSED CONSOLIDATED BALANCE SHEETS (Parenthetical) (USD $)	Mar. 31, 2015	Dec. 31, 2014
In Thousands, unless otherwise specified
Statement of Financial Position [Abstract]
Accounts receivable, allowance for doubtful accounts	$1,360	$1,275

CONDENSED_CONSOLIDATED_STATEME

CONDENSED CONSOLIDATED STATEMENTS OF OPERATIONS (USD $)	3 Months Ended
In Thousands, except Share data, unless otherwise specified	Mar. 31, 2015		Mar. 31, 2014
Revenue	$59,770		$47,828
Costs and expenses (1) (2)
Cost of revenue (3)	16,254	[1],[2],[3]	11,735	[1],[2],[3]
Sales and marketing	24,294	[1],[3]	18,395	[1],[3]
General and administrative	10,164	[1],[3]	9,499	[1],[3]
Product development	9,800	[1],[3]	8,951	[1],[3]
Amortization of purchased intangibles	1,313		190
Total costs and expenses	61,825		48,770
Loss from operations	-2,055		-942
Other expense	-231		-83
Loss before benefit from income taxes	-2,286		-1,025
Benefit from income taxes	-228		-231
Net loss	-2,058		-794
Basic net (loss) income per common share (in dollars per share)	($0.04)		($0.01)
Diluted net (loss) income per common share (in dollars per share)	($0.04)		($0.01)
Weighted average shares outstanding used in basic net (loss) income per common share calculation (in shares)	56,291,383		54,666,535
Weighted average shares outstanding used in diluted net (loss) income per common share calculation (in shares)	56,291,383		54,666,535
Stock compensation expense	2,794		2,697
Cost of revenue [Member]
Costs and expenses (1) (2)
Amortization of purchased intangibles	839		868
Stock compensation expense	328		360
Depreciation expense	1,903		1,397
Sales and marketing expense [Member]
Costs and expenses (1) (2)
Stock compensation expense	595		814
Depreciation expense	250		207
Product development expense [Member]
Costs and expenses (1) (2)
Stock compensation expense	939		680
Depreciation expense	188		177
General and administrative expense [Member]
Costs and expenses (1) (2)
Stock compensation expense	932		843
Depreciation expense	$237		$200
[1]	Amounts include depreciation expense as follows: Cost of revenue $1,732 and $1,445 for the three months ended September 30, 2014 and 2013, respectively and $4,776 and $4,565 for the nine months ended September 30, 2014 and 2013, respectively, Sales and marketing $195 and $23 for the three months ended September 30, 2014 and 2013, respectively and $603 and $68 for the nine months ended September 30, 2014 and 2013, respectively, Product development $180 and $166 for the three months ended September 30, 2014 and 2013, respectively and $529 and $526 for the nine months ended September 30, 2014 and 2013, respectively, and General and administrative $237 and $368 for the three months ended September 30, 2014 and 2013, respectively and $651 and $891 for the nine months ended September 30, 2014 and 2013, respectively.
[2]	3) Amounts include amortization expense as follows: Cost of revenue $1,732 and $1,445 for the three months ended March 31, 2015 and 2014, respectively.
[3]	Amounts include stock compensation expense as follows: Cost of revenue $365 and $635 for the three months ended September 30, 2014 and 2013, respectively and $1209 and $1557 for the nine months ended September 30, 2014 and 2013, respectively, Sales and marketing $1030 and $844 for the three months ended September 30, 2014 and 2013, respectively and $2,766 and $2,159 for the nine months ended September 30, 2014 and 2013, respectively, Product development $1,171 and $1,241 for the three months ended September 30, 2014 and 2013, respectively and $2,783 and $2,922 for the nine months ended September 30, 2014 and 2013, respectively, and General and administrative $1,088 and $1,078 for the three months ended September 30, 2014 and 2013, respectively and $2,800 and $3,111 for the nine months ended September 30, 2014 and 2013, respectively.

CONDENSED_CONSOLIDATED_STATEME1

CONDENSED CONSOLIDATED STATEMENTS OF COMPREHENSIVE (LOSS) INCOME (USD $)	3 Months Ended
In Thousands, unless otherwise specified	Mar. 31, 2015	Mar. 31, 2014
Statement of Comprehensive Income [Abstract]
Net loss	($2,058)	($794)
Foreign currency translation adjustment	-989	140
Comprehensive loss	($3,047)	($654)

CONDENSED_CONSOLIDATED_STATEME2

CONDENSED CONSOLIDATED STATEMENTS OF CASH FLOWS (USD $)	3 Months Ended
In Thousands, unless otherwise specified	Mar. 31, 2015	Mar. 31, 2014
OPERATING ACTIVITIES:
Net loss	($2,058)	($794)
Adjustments to reconcile net loss to net cash used in operating activities:
Stock-based compensation expense	2,794	2,697
Depreciation	2,578	1,981
Amortization of purchased intangibles	2,152	1,058
Deferred income taxes and other non-cash tax items	820	-76
Provision for doubtful accounts, net	403	271
Changes in operating assets and liabilities:
Accounts receivable	-4,609	48
Prepaid expenses and other current assets	-2,544	-3,930
Other assets	-15	460
Accounts payable	1,359	1,114
Accrued expenses and other current liabilities	-7,045	-3,828
Deferred revenue	-1,776	-1,586
Other liabilities	361	-414
Net cash used in operating activities	-7,580	-2,999
INVESTING ACTIVITIES:
Purchases of property and equipment, including capitalized software	-1,783	-1,456
Investment in technology licenses	0	-3,174
Payments for acquisitions and intangible assets, net of cash acquired	0	-125
Net cash used in investing activities	-1,783	-4,755
FINANCING ACTIVITIES:
Excess tax benefit from the exercise of employee stock options	751	0
Proceeds from issuance of common stock in connection with the exercise of options	2,284	2,978
Repurchase of common stock	-2,058	-7,841
Net cash provided by (used in) financing activities	977	-4,863
EFFECT OF FOREIGN EXCHANGE RATE CHANGES ON CASH AND CASH EQUIVALENTS	-150	84
CHANGE IN CASH AND CASH EQUIVALENTS	-8,536	-12,533
CASH AND CASH EQUIVALENTS - Beginning of the period	49,372	91,906
CASH AND CASH EQUIVALENTS - End of the period	40,836	79,373
SUPPLEMENTAL DISCLOSURE OF OTHER CASH FLOW INFORMATION:
Cash paid for income taxes	583	1,037
SUPPLEMENTAL DISCLOSURE OF NON-CASH INVESTING AND FINANCING ACTIVITIES:
Purchase of property and equipment recorded in accounts payable	2,224	1,174
Acquisition costs in connection with NexGraph recorded in accrued expenses	$0	$375

Description_of_Business_and_Ba

Description of Business and Basis of Presentation	3 Months Ended
	Mar. 31, 2015
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 offices in Amsterdam, Atlanta, Berlin, London, Mannheim, Melbourne, Milan, Ra'anana, Reading (UK), San Francisco and Tokyo.
	LivePerson provides online engagement solutions offering a cloud-based platform which enables businesses to proactively connect with consumers through chat, voice and content delivery, across multiple channels and screens, including websites, social media, tablets and mobile devices. The Company’s engagements are driven by insights derived from a broad set of consumer and business data, including historical, behavioral, operational, and third party data. Each engagement is based on proprietary analytics and a real-time understanding of consumer needs and business objectives. The Company’s products, coupled with its domain knowledge and industry expertise, have been proven to maximize the effectiveness of the online channel — by increasing sales, as well as consumer satisfaction and loyalty ratings for its customers, while also enabling its customers to reduce consumer service costs.
	LivePerson monitors and analyzes valuable online consumer behavioral data on behalf of its customers. Spanning the breadth of an online visitor session, starting from an initial keyword search through actions on their customer’s website, and even into a shopping cart and an executed sale, this data enables the Company to develop unique insights into consumer behavior during specific transactions within a customer’s user base.
	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 real-time chat with individual consumers (“Users”).
	Basis of Presentation
	The accompanying condensed consolidated financial statements as of March 31, 2015 and for the three months ended March 31, 2015 and 2014 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 March 31, 2015, and the consolidated results of operations, comprehensive loss and cash flows for the interim periods ended March 31, 2015 and 2014. 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, 2014 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, 2014, included in the Company’s Annual Report on Form 10-K filed with the SEC on March 12, 2015.
	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
	On February 18, 2015, the Financial Accounting Standards Board (“FASB”) issued Accounting Standards Update (“ASU”) 2015-02, Consolidation: Amendments to the Consolidation Analysis (“ASU 2015-02”), which affects reporting entities that are required to evaluate whether they should consolidate certain legal entities. All legal entities are subject to reevaluation under the revised consolidation model. The standard amends the consolidation requirements in ASC 810. ASU 2015-02 is effective for fiscal periods beginning after December 15, 2015 for public companies, and early adoption is permitted. The Company does not expect to early adopt ASU 2015-02, which will be effective for its fiscal year ending December 31, 2016. The Company does not believe the standard will have a material impact on its consolidated financial statements.
	In May 2014, the FASB issued ASU 2014-09, Revenue from Contracts with Customers (“ASU 2014-09”), which supersedes most existing revenue recognition guidance under GAAP. The core principle of ASU 2014-09 is to recognize revenues when promised goods or services are transferred to customers in an amount that reflects the consideration to which an entity expects to be entitled for those goods or services. ASU 2014-09 defines a five step process to achieve this core principle and, in doing so, more judgment and estimates may be required within the revenue recognition process than are required under existing GAAP. The standard is effective for annual periods beginning after December 15, 2016, and interim periods therein, using either of the following transition methods: (i) a full retrospective approach reflecting the application of the standard in each prior reporting period with the option to elect certain practical expedients, or (ii) a retrospective approach with the cumulative effect of initially adopting ASU 2014-09 recognized at the date of adoption (which includes additional footnote disclosures).

Revenue_Recognition

Revenue Recognition	3 Months Ended
	Mar. 31, 2015
Revenue Recognition [Abstract]
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. Because the Company provides its application as a service, the Company follows the provisions of FASB Accounting Standards Codification (“ASC”) 605-10-S99, “Revenue Recognition” and ASC 605-25, “Revenue Recognition with Multiple-Element Arrangements.” The Company charges a monthly fee, which varies by type of service, the level of customer usage and website traffic, and in some cases, the number of orders placed via the Company’s online engagement solutions.
	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 605-45, “Principal Agent Considerations,” the Company records revenue for transactions in which it acts as an agent on a net basis, and revenue for transactions in which it acts as a principal on a gross basis.
	The Company also sells certain of the LivePerson services directly via Internet download.  These services are marketed as LiveEngage for small to medium-sized businesses, and are paid for almost exclusively by credit card.  Credit card payments accelerate cash flow and reduce the Company’s collection risk, subject to the merchant bank's right to hold back cash pending settlement of the transactions.  Sales of LiveEngage may occur with or without the assistance of an online sales representative, rather than through face-to-face or telephone contact that is typically required for traditional direct sales.
	The Company recognizes monthly service revenue based upon the fee charged for the LivePerson services, provided that there is persuasive evidence of an arrangement, no significant Company obligations remain, collection of the resulting receivable is probable and the amount of fees to be paid is fixed or determinable. The Company’s service agreements typically have twelve month terms and, in some cases, are terminable or may terminate upon 30 to 90 days’ notice without penalty. When professional service fees add value to the customer on a standalone basis, the Company recognizes professional service fees upon completion and customer acceptance. ASU 2009-13 establishes a selling price hierarchy for determining the selling price of a deliverable, which is based on: (a) vendor-specific objective evidence; (b) third-party evidence; or (c) best estimated selling price. If a professional services arrangement does not qualify for separate accounting, the Company recognizes the fees, and the related labor costs, ratably over the contracted period.
	For revenue from the Company's Consumer segment generated from online transactions between Experts and Users, the Company recognizes revenue net of the Expert fees in accordance with ASC 605-45, “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 User and retains a portion of the fee, and then remits the balance to the Expert. Revenue from these transactions is recognized when there is persuasive evidence of an arrangement, no significant Company obligations remain, collection of the resulting receivable is probable and the amount of fees to be paid is fixed and determinable.

Net_Loss_Per_Share

Net Loss Per Share	3 Months Ended
	Mar. 31, 2015
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 three months ended March 31, 2015 and 2014 does not include the effect of options to purchase 10,152,741 and 9,678,582 shares of common stock, respectively, as the effect of their inclusion is anti-dilutive.
	A reconciliation of shares used in calculating basic and diluted earnings per share follows:
		Three Months Ended
		March 31,
		2015	2014
	Basic	56,291,383	54,666,535
	Effect of assumed exercised options	—	—
	Diluted	56,291,383	54,666,535

Segment_Information

Segment Information	3 Months Ended
	Mar. 31, 2015
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 facilitates real-time online interactions – chat, voice and content delivery across multiple channels and screens for global corporations of all sizes. The Consumer segment facilitates online transactions between Experts and Users and sells its services to consumers. 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 condensed 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 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 three months ended March 31, 2015, 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	$	50,613	$	—	$	—		$	50,613
	Hosted services – Consumer	—		3,696		—			3,696
	Professional services	5,461		—		—			5,461
	Total revenue	56,074		3,696		—			59,770
	Cost of revenue	15,617		637		—			16,254
	Sales and marketing	22,852		1,442		—			24,294
	Amortization of purchased intangibles	1,313		—		—			1,313
	Unallocated corporate expenses	—		—		19,964			19,964
	Operating income (loss)	$	16,292	$	1,617	$	(19,964	)	$	(2,055	)
	Summarized financial information by segment for the three months ended March 31, 2014, 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	$	39,680	$	—	$	—		$	39,680
	Hosted services – Consumer	—		3,910		—			3,910
	Professional services	4,238		—		—			4,238
	Total revenue	43,918		3,910		—			47,828
	Cost of revenue	11,220		515		—			11,735
	Sales and marketing	16,918		1,477		—			18,395
	Amortization of purchased intangibles	190		—		—			190
	Unallocated corporate expenses	—		—		18,450			18,450
	Operating income (loss)	$	15,590	$	1,918	$	(18,450	)	$	(942	)
	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 revenues attributable to domestic and foreign operations for the periods presented (amounts in thousands):
		Three Months Ended
		March 31,
		2015		2014
	United States	$	41,442	$	31,098
	Other Americas (1)	2,703		2,150
	Total Americas	44,145		33,248
	EMEA (2)	11,784		10,515
	APAC (3)	3,841		4,065
	Total revenue	$	59,770	$	47,828
	(1) Canada, Latin America and South America
	(2) Europe, the Middle East and Africa (“EMEA”)
	(3) Asia-Pacific (“APAC”)
	The following table presents the Company's long-lived assets by geographic region for the periods presented (amounts in thousands):
		March 31,		December 31,
		2015		2014
	United States	$	109,517	$	109,006
	Israel	18,173		18,982
	Australia	8,132		8,500
	Netherlands	7,709		7,686
	Other (1)	1,978		1,940
	Total long-lived assets	$	145,509	$	146,114
	(1) United Kingdom, Germany, Japan and Italy
	No individual customer accounted for 10% or more of consolidated revenue for any of the periods presented. One customer accounted for approximately 16% and 22% of accounts receivable as of March 31, 2015 and December 31, 2014, respectively.

Goodwill_and_Intangible_Assets

Goodwill and Intangible Assets	3 Months Ended
	Mar. 31, 2015
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 three months ended March 31, 2015 are as follows (amounts in thousands):
		Business			Consumer			Total
	Balance as of December 31, 2014	$	72,824		$	8,024		$	80,848
	Adjustments to goodwill:
	Foreign exchange adjustment	(538		)	—			(538		)
	Balance as of March 31, 2015	$	72,286		$	8,024		$	80,310
	The changes in the carrying amount of goodwill for the year ended December 31, 2014 are as follows (amounts in thousands):
		Business			Consumer			Total
	Balance as of December 31, 2013	$	24,700		$	8,024		$	32,724
	Adjustments to goodwill:
	Acquisitions	48,124			—			48,124
	Balance as of December 31, 2014	$	72,824		$	8,024		$	80,848
	Intangible Assets
	Intangible assets are summarized as follows (see Note 8) (amounts in thousands):
		As of March 31, 2015
		Gross			Accumulated			Net Carrying Amount			Weighted
		Carrying			Amortization						Average
		Amount									Amortization
											Period
	Amortizing intangible assets:
	Technology	$	28,005		$	(12,379	)	$	15,626		5.3 years
	Customer relationships	16,008			(4,818		)	11,190			7.9 years
	Trade names	1,287			(946		)	341			2.8 years
	Non-compete agreements	1,446			(721		)	725			2.3 years
	Patents	3,290			(584		)	2,706			9.9 years
	Other	312			(271		)	41			3.0 years
	Total	$	50,348		$	(19,719	)	$	30,629
		As of December 31, 2014
		Gross			Accumulated			Net Carrying Amount			Weighted
		Carrying			Amortization						Average
		Amount									Amortization
											Period
	Amortizing intangible assets:
	Technology	$	27,844		$	(11,303	)	$	16,541		5.3 years
	Customer relationships	16,008			(4,055		)	11,953			7.9 years
	Trade names	1,287			(817		)	470			2.8 years
	Non-compete agreements	1,446			(625		)	821			2.3 years
	Patents	3,290			(500		)	2,790			9.9 years
	Other	312			(267		)	45			3.0 years
	Total	$	50,187		$	(17,567	)	$	32,620
	Amortization expense is calculated over the estimated useful life of the asset. Aggregate amortization expense for intangible assets was $2.2 million and $1.1 million for the three months ended March 31, 2015 and 2014, respectively. For the three months ended March 31, 2015 and 2014, respectively, a portion of this amortization is included in cost of revenue. Estimated amortization expense for the next five years is as follows (amounts in thousands):
		Estimated Amortization Expense
	2015	$	5,828
	2016	6,755
	2017	4,934
	2018	2,815
	2019	2,809
	Thereafter	7,488
	Total	$	30,629

Property_and_Equipment

Property and Equipment	3 Months Ended
	Mar. 31, 2015
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):
		March 31,			December 31,
		2015			2014
	Computer equipment and software	$	59,122		$	55,293
	Furniture, equipment and building improvements	9,578			9,439
		68,700			64,732
	Less: accumulated depreciation	(47,727		)	(45,149		)
	Total	$	20,973		$	19,583

Accrued_Liabilities

Accrued Liabilities	3 Months Ended
	Mar. 31, 2015
Payables and Accruals [Abstract]
Accrued Liabilities	Accrued and Other Current Liabilities
	The following table presents the detail of accrued and other current liabilities for the periods presented (amounts in thousands):
		March 31,		December 31,
		2015		2014
	Payroll and other employee related costs	$	10,893	$	15,373
	Professional services and consulting and other vendor fees	9,730		9,258
	Sales commissions	1,448		3,268
	Contingent earnout (see Notes 8 and 9)	6,591		6,940
	Other	2,869		2,933
	Total	$	31,531	$	37,772

Acquisitions

Acquisitions	3 Months Ended
	Mar. 31, 2015
Business Combinations [Abstract]
Acquisitions	Acquisitions
	Engage Pty Ltd.
	On November 9, 2012, the Company acquired all of the outstanding shares of Engage Pty Ltd. (“Engage”), an Australian provider of cloud-based customer contact solutions. The transaction was accounted for under the purchase method of accounting and, accordingly, the operating results of Engage were included in the Company’s consolidated results of operations from the date of acquisition.
	The purchase price was approximately $10.6 million. The total acquisition costs incurred in the year ended December 31, 2012 were approximately $0.5 million and are included in general and administrative expenses in the Company’s condensed consolidated statements of operations for the same period. The acquisition enhances the Company’s ability to offer intelligent engagement solutions to businesses in the Asia Pacific region. Of the total purchase price, $0.8 million was allocated to the net book values of the acquired assets and assumed liabilities. The historical carrying amounts of such assets and liabilities approximated their fair values. All receivables acquired are expected to be collectible. The purchase price in excess of the fair value of the net book values of the assets acquired and liabilities assumed was allocated to intangible assets based on management’s best estimate of fair values, taking into account all relevant information available at the time of acquisition, and the excess was allocated to goodwill. The goodwill is not deductible for tax purposes. The intangible assets are being amortized over their expected period of benefit. The purchase price includes approximately $1.7 million of potential earn-out consideration for the shareholders if certain revenue targets are achieved. The earn-out is payable in shares of LivePerson common stock and cash. The Company recorded the contingent earn-out as part of the purchase price. In accordance with ASC 480, the Company has classified this amount as a liability and the amount is included in accrued expenses in the March 31, 2015 condensed consolidated balance sheets, due to the variable number of shares that will be issued if and when the targets are achieved. The Company assessed this earn-out at March 31, 2015 with no change from the original estimate. There was a decrease in the liability during the quarter ended March 31, 2015 as a result of a payment made of $0.3 million. The Company will assess the earn-out calculation in future periods and any future adjustments will affect operating income.
	NexGraph, LLC
	On March 11, 2014, the Company acquired all the outstanding shares of NexGraph, LLC (“NexGraph”), a company focused on analytic solutions, in exchange for aggregate cash consideration of $0.5 million. Of the purchase price, $0.1 million was allocated to Intangibles, net, of which was fully amortized as of March 31, 2015; and $0.4 million of the purchase price was allocated to Goodwill.
	Synchronite, LLC
	On June 2, 2014, the Company acquired Synchronite, LLC (“Synchronite”), a German-based start-up that provides co-browsing technology. The transaction was accounted for under the purchase method of accounting and, accordingly, the operating results of Synchronite were included in the Company’s consolidated results of operations from the date of acquisition.
	The allocation of the total purchase price of approximately $4.1 million was based upon the estimated fair value of Synchronite's net tangible and identifiable intangible assets as of the date of acquisition. The total acquisition costs incurred were approximately $0.4 million and are included in general and administrative expenses in the Company’s condensed consolidated statements of operations. Of the total purchase price, $45,000 was allocated to the net book values of the acquired assets and assumed liabilities. The historical carrying amounts of such assets and liabilities approximated their fair values. All receivables acquired are expected to be collectible. The purchase price includes approximately $2.7 million of goodwill and approximately $1.5 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 purchase price includes $1.8 million of potential earn-out consideration for the shareholders if complete product integration is achieved. The earn-out is payable in shares of LivePerson common stock and cash. The Company recorded the contingent earn-out as part of the purchase price. In accordance with ASC 480, the Company has classified this amount as a liability and the amount is included in accrued expenses in the March 31, 2015 condensed consolidated balance sheet, due to the variable number of shares that will be issued if and when the targets are achieved. The Company has assessed the earn-out calculation at March 31, 2015, with no change from the original estimate, and will assess the earn-out calculation in future periods and any future adjustments will affect operating income.
	The components of the intangible assets are as follows (amounts in thousands):
		Weighted		Amount
		Average Useful
		Life (Months)
	Technology	120		$	1,082
	Trade-name	48		62
	Customer relationships	84		247
	Non-compete agreements	36		60
				$	1,451
	Contact At Once!, LLC
	On November 7, 2014, the Company acquired Contact At Once!, LLC (“CAO!”), a software company with a cloud-based platform that instantly connects consumers with businesses through instant messaging, text messaging, chat, social media and video over the internet for consumer-to-business sales conversions. The transaction was accounted for under the purchase method of accounting and, accordingly, the operating results of CAO! were included in the Company’s consolidated results of operations from the date of acquisition. The Company is in the process of finalizing all fair value and purchase accounting adjustments.
	The allocation of the total purchase price of approximately $67.0 million, which includes approximately $42.8 million in cash, approximately $20.0 million in shares of common stock and approximately $4.2 million of potential earn-out consideration in cash, was based upon the estimated fair value of CAO!'s net tangible and identifiable intangible assets as of the date of acquisition. The historical carrying amounts of such assets and liabilities approximated their fair values. All receivables acquired are expected to be collectible. The purchase price includes approximately $45.1 million of goodwill and approximately $20.4 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 purchase price includes $4.2 million of potential earn-out consideration for the shareholders if certain targeted financial, strategic and integration objectives is achieved. The earn-out is payable in cash. The Company recorded the contingent earn-out as part of the purchase price. In accordance with ASC 480, the Company has classified this amount as a liability and is included in accrued expenses in the December 31, 2014 consolidated balance sheet. The Company has assessed this earn-out at March 31, 2015, with no change from the original estimate, and will assess the earn-out calculation in future periods and any future adjustments will affect operating income.
	Management’s preliminary allocation of the purchase price in connection with the CAO! acquisition is as follows (amounts in thousands):
	Cash	$	480
	Accounts receivable	2,694
	Other currents assets	289
	Property and equipment	231
	Other assets	43
	Intangible assets	20,400
	Goodwill	45,064
		69,201
	Liabilities assumed	(2,203		)
	Total purchase price consideration	$	66,998
	The components of the intangible assets are as follows (amounts in thousands):
		Weighted		Amount
		Average Useful
		Life (Months)
	Technology	96		$	8,400
	Trade-name	12		500
	Customer relationships	120		10,700
	Non-compete agreements	36		800
				$	20,400

Fair_Value_Measurements

Fair Value Measurements	3 Months Ended
	Mar. 31, 2015
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 Company's assets and liabilities that are measured at fair value on a recurring basis, by level, within the fair value hierarchy as of March 31, 2015 and December 31, 2014, are summarized as follows (amounts in thousands):
		March 31, 2015												December 31, 2014
		Level 1				Level 2				Level 3		Total		Level 1		Level 2		Level 3		Total
	Assets:
	Cash equivalents:
	Money market funds	$	3,088			$	—			$	—	$	3,088	$	3,987	$	—	$	—	$	3,987
	Total assets	$	3,088			$	—			$	—	$	3,088	$	3,987	$	—	$	—	$	3,987
	Liabilities:
	Contingent earn-out	$	—			$	—			$	6,590	$	6,590	$	—	$	—	$	6,940	$	6,940
	Foreign currency derivative contracts	—				423				—		423		—		—		—		—
	Total liabilities	$	—			$	423			$	6,590	$	7,013	$	—	$	—	$	6,940	$	6,940
	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 only asset that is measured at fair value on a recurring basis is money market funds, based on quoted market prices in active markets and therefore classified as level 1 within the fair value hierarchy. The Company's contingent earn-out liability and foreign currency derivative contract liability are measured at fair value on a recurring basis and are classified as level 3 and level 2, respectively, 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 a combination of discounted cash flows and other 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.
	The contingent earn-out in connection with the acquisition of Engage is $0.7 million and $0.9 million as of March 31, 2015 and December 31, 2014, respectively, and is recorded in accrued expenses in the condensed consolidated balance sheets. This earn-out is based on the potential earn-out consideration if certain revenue targets are achieved. The contingent earn-out balance was increased by $1.8 million in June 2014 in connection with the acquisition of Synchronite and $4.2 million in November 2014 in connection with the acquisition of CAO!. The contingent earn-out amounts are recorded in accrued expense on the condensed consolidated balance sheets as they are payable in 2015. The contingent earn-out relating to Synchronite is based on the fulfillment of a complete product integration and a minimum number of “Co-Browse” interactions per month. The contingent earn-out relating to CAO! is based on achieving certain target financial, strategic and integration objectives and milestones.
	The changes in fair value of the Level 3 liabilities are as follows (amounts in thousands):
		Contingent Earn-Out
		31-Mar-15				31-Dec-14
	Balance, Beginning of Period	$	6,940			$	1,660
	Synchronite addition (see Note 8)	—				1,810
	CAO! addition (see Note 8)	—				4,220
	Cash payment	(350		)		(750		)
	Balance, End of Period	$	6,590			$	6,940
	Derivative Financial Instruments
	The Company is exposed to foreign exchange risks that in part are managed by using derivative financial instruments. Beginning January 2015, the Company entered into foreign currency forward contracts related to risks associated with foreign operations. The Company does not use derivatives for trading purposes and at March 31, 2015 has no derivatives that are designated as fair value hedges. 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.
	The following summarizes certain information regarding the Company’s outstanding foreign currency derivative contracts related primarily to intercompany receivables and payables for the periods presented (in thousands):
			31-Mar-15				31-Mar-14
	Notional amount of foreign currency derivative contracts		$	38,236			$	—
	Fair value of foreign currency derivatives contracts		$	423			$	—
	The fair value of the Company's derivative instruments are summarized below (in thousands):
					Fair Value of Derivative Instruments
			Balance Sheet Location		31-Mar-15				31-Mar-14
	Derivative Liabilities
	Derivatives not designated as hedging instruments:
	Foreign currency derivatives contracts		Accrued expenses and other liabilities		$	423			$	—
	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 Income Statement
			Location		31-Mar-15				31-Mar-14
	Foreign currency derivatives contracts		Other expense		$	7			$	—

Commitments_and_Contingencies

Commitments and Contingencies	3 Months Ended
	Mar. 31, 2015
Commitments and Contingencies Disclosure [Abstract]
Commitments and Contingencies	Commitments and Contingencies
	Contractual Obligations
	The Company leases facilities and certain equipment under agreements accounted for as operating leases. These leases generally require the Company to pay all executory costs such as maintenance and insurance. Rental expense for operating leases for the three months ended March 31, 2015 and 2014 was approximately $2.5 million and $2.2 million, respectively.
	Employee Benefit Plans
	The Company has a 401(k) defined contribution plan covering all eligible employees. The Company provides 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. Salaries and related expenses include $0.4 million and $0.3 million of employer matching contributions for the three months ended March 31, 2015 and 2014, respectively.

Stockholders_Equity

Stockholders' Equity	3 Months Ended
	Mar. 31, 2015
Disclosure of Compensation Related Costs, Share-based Payments [Abstract]
Stockholders' Equity	Stockholders' Equity
	Common Stock
	As of March 31, 2015, there were 100,000,000 shares of common stock authorized, and 57,039,125 shares issued and outstanding. As of December 31, 2014, there were 100,000,000 shares of common stock authorized, and 56,701,331 shares issued and outstanding. The par value for common shares is $0.001.
	Preferred Stock
	As of March 31, 2015 and December 31, 2014, 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
	On December 10, 2012, the Company’s Board of Directors approved a stock repurchase program through June 30, 2014. Under the stock repurchase program, the Company is 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. On March 13, 2014, the Company's Board of Directors increased the aggregate purchase price of the stock repurchase program from $30.0 million to $40.0 million. On July 23, 2014, the Company's Board of Directors increased the aggregate purchase price of the stock repurchase program from $40.0 million to $50.0 million. On March 5, 2015, the Company's Board of Directors extended the expiration date of the program out to December 31, 2016. There were 176,172 shares repurchased under this program during 2015, of which 33,360 shares were recorded in treasury stock at par on the condensed consolidated balance sheets as of March 31, 2015. As of March 31, 2015, approximately $8.2 million remained available for purchase under the program.
	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 (with limited exceptions). Incremental compensation costs arising from subsequent modifications of awards after the grant date must be recognized.
	The following table summarizes stock-based compensation expense related to employee stock options under ASC 718-10 included in Company’s statements of operations for the periods presented (amounts in thousands):
		Three Months Ended
		March 31,
		2015				2014
	Cost of revenue	$	328			$	360
	Sales and marketing expense	595				814
	Product development expense	939				680
	General and administrative expense	932				843
	Total stock based compensation included in costs and expenses	$	2,794			$	2,697
	The per share weighted average fair value of stock options granted during the three months ended March 31, 2015 and 2014 was $4.64 and $6.25, 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:
		Three Months Ended
		March 31,
		2015		2014
	Dividend yield	0.00%		0.00%
	Risk-free interest rate	1.30%		1.50%
	Expected life (in years)	5		5
	Historical volatility	49.70%		53.70%
	A description of the methods used in the significant assumptions used to estimate the fair value of stock-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 (as amended and restated, 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 stock incentive 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, thereby reserving for issuance 23,817,744 shares of common stock in the aggregate. Options to acquire common stock granted thereunder have 10-year terms. As of March 31, 2015, approximately 13,100,000 shares of common stock were reserved for issuance under the 2009 Plan (taking into account all option exercises through March 31, 2015).
	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. As of March 31, 2015, approximately 519,000 shares of common stock were reserved for issuance under the Employee Stock Purchase Plan (taking into account all share purchases through March 31, 2015).
	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			Weighted
					Average
					Exercise Price
	Balance outstanding at December 31, 2014	10,769,149			$	10.95
	Granted	434,550			10.53
	Exercised	(430,533	)		4.03
	Cancelled or expired	(620,425	)		12.38
	Balance outstanding at March 31, 2015	10,152,741			$	11.13		7.31	$	9,027
	Options vested and expected to vest at March 31, 2015	8,600,976			$	11.13		7.01	$	8,766
	Options exercisable at March 31, 2015	4,354,151			$	10.5		5.68	$	7,900
	The total fair value of stock options exercised during the three months ended March 31, 2015 was approximately $1.1 million. As of March 31, 2015, there was approximately $25.6 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 2.6 years.
	A summary of the status of the Company’s nonvested shares as of December 31, 2014, and changes during the three months ended March 31, 2015 is as follows:
		Options			Weighted
					Average Grant-
					Date Fair Value
	Nonvested Shares at December 31, 2014	6,032,315			$	5.66
	Granted	434,550			4.64
	Vested	(47,850	)		5.1
	Cancelled or expired	(620,425	)		6.09
	Nonvested Shares at March 31, 2015	5,798,590			$	5.59
	The total intrinsic value of nonvested options at March 31, 2015 was approximately $1.1 million.

Legal_Matters

Legal Matters	3 Months Ended
	Mar. 31, 2015
Commitments and Contingencies Disclosure [Abstract]
Legal Matters	Legal Matters
	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 disclosures 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 out of 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 our 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.

Description_of_Business_and_Ba1

Description of Business and Basis of Presentation (Policies)	3 Months Ended
	Mar. 31, 2015
Accounting Policies [Abstract]
SUMMARY OF OPERATIONS	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 offices in Amsterdam, Atlanta, Berlin, London, Mannheim, Melbourne, Milan, Ra'anana, Reading (UK), San Francisco and Tokyo.
	LivePerson provides online engagement solutions offering a cloud-based platform which enables businesses to proactively connect with consumers through chat, voice and content delivery, across multiple channels and screens, including websites, social media, tablets and mobile devices. The Company’s engagements are driven by insights derived from a broad set of consumer and business data, including historical, behavioral, operational, and third party data. Each engagement is based on proprietary analytics and a real-time understanding of consumer needs and business objectives. The Company’s products, coupled with its domain knowledge and industry expertise, have been proven to maximize the effectiveness of the online channel — by increasing sales, as well as consumer satisfaction and loyalty ratings for its customers, while also enabling its customers to reduce consumer service costs.
	LivePerson monitors and analyzes valuable online consumer behavioral data on behalf of its customers. Spanning the breadth of an online visitor session, starting from an initial keyword search through actions on their customer’s website, and even into a shopping cart and an executed sale, this data enables the Company to develop unique insights into consumer behavior during specific transactions within a customer’s user base.
	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 real-time chat with individual consumers (“Users”).
BASIS OF PRESENTATION	Basis of Presentation
	The accompanying condensed consolidated financial statements as of March 31, 2015 and for the three months ended March 31, 2015 and 2014 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 March 31, 2015, and the consolidated results of operations, comprehensive loss and cash flows for the interim periods ended March 31, 2015 and 2014. 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, 2014 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, 2014, included in the Company’s Annual Report on Form 10-K filed with the SEC on March 12, 2015.
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. Because the Company provides its application as a service, the Company follows the provisions of FASB Accounting Standards Codification (“ASC”) 605-10-S99, “Revenue Recognition” and ASC 605-25, “Revenue Recognition with Multiple-Element Arrangements.” The Company charges a monthly fee, which varies by type of service, the level of customer usage and website traffic, and in some cases, the number of orders placed via the Company’s online engagement solutions.
	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 605-45, “Principal Agent Considerations,” the Company records revenue for transactions in which it acts as an agent on a net basis, and revenue for transactions in which it acts as a principal on a gross basis.
	The Company also sells certain of the LivePerson services directly via Internet download.  These services are marketed as LiveEngage for small to medium-sized businesses, and are paid for almost exclusively by credit card.  Credit card payments accelerate cash flow and reduce the Company’s collection risk, subject to the merchant bank's right to hold back cash pending settlement of the transactions.  Sales of LiveEngage may occur with or without the assistance of an online sales representative, rather than through face-to-face or telephone contact that is typically required for traditional direct sales.
	The Company recognizes monthly service revenue based upon the fee charged for the LivePerson services, provided that there is persuasive evidence of an arrangement, no significant Company obligations remain, collection of the resulting receivable is probable and the amount of fees to be paid is fixed or determinable. The Company’s service agreements typically have twelve month terms and, in some cases, are terminable or may terminate upon 30 to 90 days’ notice without penalty. When professional service fees add value to the customer on a standalone basis, the Company recognizes professional service fees upon completion and customer acceptance. ASU 2009-13 establishes a selling price hierarchy for determining the selling price of a deliverable, which is based on: (a) vendor-specific objective evidence; (b) third-party evidence; or (c) best estimated selling price. If a professional services arrangement does not qualify for separate accounting, the Company recognizes the fees, and the related labor costs, ratably over the contracted period.
	For revenue from the Company's Consumer segment generated from online transactions between Experts and Users, the Company recognizes revenue net of the Expert fees in accordance with ASC 605-45, “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 User and retains a portion of the fee, and then remits the balance to the Expert. Revenue from these transactions is recognized when there is persuasive evidence of an arrangement, no significant Company obligations remain, collection of the resulting receivable is probable and the amount of fees to be paid is fixed and determinable.
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 three months ended March 31, 2015 and 2014 does not include the effect of options to purchase 10,152,741 and 9,678,582 shares of common stock, respectively, as the effect of their inclusion is anti-dilutive.
	A reconciliation of shares used in calculating basic and diluted earnings per share follows:
		Three Months Ended
		March 31,
		2015	2014
	Basic	56,291,383	54,666,535
	Effect of assumed exercised options	—	—
	Diluted	56,291,383	54,666,535
SEGMENT REPORTING	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 facilitates real-time online interactions – chat, voice and content delivery across multiple channels and screens for global corporations of all sizes. The Consumer segment facilitates online transactions between Experts and Users and sells its services to consumers. 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 condensed 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 and income tax expense because management does not use this information to measure performance of the operating segments.
GOODWILL AND INTANGIBLE ASSETS	Amortization expense is calculated over the estimated useful life of the asset.
STOCK-BASED COMPENSATION	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 (with limited exceptions). Incremental compensation costs arising from subsequent modifications of awards after the grant date must be recognized.

Net_Loss_Per_Share_Tables

Net Loss Per Share (Tables)	3 Months Ended
	Mar. 31, 2015
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:
		Three Months Ended
		March 31,
		2015	2014
	Basic	56,291,383	54,666,535
	Effect of assumed exercised options	—	—
	Diluted	56,291,383	54,666,535

Segment_Information_Tables

Segment Information (Tables)	3 Months Ended
	Mar. 31, 2015
Segment Reporting [Abstract]
Summary of Financial Information by Segment	Summarized financial information by segment for the three months ended March 31, 2015, 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	$	50,613	$	—	$	—		$	50,613
	Hosted services – Consumer	—		3,696		—			3,696
	Professional services	5,461		—		—			5,461
	Total revenue	56,074		3,696		—			59,770
	Cost of revenue	15,617		637		—			16,254
	Sales and marketing	22,852		1,442		—			24,294
	Amortization of purchased intangibles	1,313		—		—			1,313
	Unallocated corporate expenses	—		—		19,964			19,964
	Operating income (loss)	$	16,292	$	1,617	$	(19,964	)	$	(2,055	)
	Summarized financial information by segment for the three months ended March 31, 2014, 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	$	39,680	$	—	$	—		$	39,680
	Hosted services – Consumer	—		3,910		—			3,910
	Professional services	4,238		—		—			4,238
	Total revenue	43,918		3,910		—			47,828
	Cost of revenue	11,220		515		—			11,735
	Sales and marketing	16,918		1,477		—			18,395
	Amortization of purchased intangibles	190		—		—			190
	Unallocated corporate expenses	—		—		18,450			18,450
	Operating income (loss)	$	15,590	$	1,918	$	(18,450	)	$	(942	)
Revenues Attributable to Domestic and Foreign Operations	The following table presents the Company’s revenues attributable to domestic and foreign operations for the periods presented (amounts in thousands):
		Three Months Ended
		March 31,
		2015		2014
	United States	$	41,442	$	31,098
	Other Americas (1)	2,703		2,150
	Total Americas	44,145		33,248
	EMEA (2)	11,784		10,515
	APAC (3)	3,841		4,065
	Total revenue	$	59,770	$	47,828
	(1) Canada, Latin America and South America
	(2) Europe, the Middle East and Africa (“EMEA”)
	(3) Asia-Pacific (“APAC”)
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):
		March 31,		December 31,
		2015		2014
	United States	$	109,517	$	109,006
	Israel	18,173		18,982
	Australia	8,132		8,500
	Netherlands	7,709		7,686
	Other (1)	1,978		1,940
	Total long-lived assets	$	145,509	$	146,114
Long Lived Assets By Geography [Table Text Block]	The following table presents the Company's long-lived assets by geographic region for the periods presented (amounts in thousands):
		March 31,		December 31,
		2015		2014
	United States	$	109,517	$	109,006
	Israel	18,173		18,982
	Australia	8,132		8,500
	Netherlands	7,709		7,686
	Other (1)	1,978		1,940
	Total long-lived assets	$	145,509	$	146,114
	(1) United Kingdom, Germany, Japan and Italy

Goodwill_and_Intangible_Assets1

Goodwill and Intangible Assets (Tables)	3 Months Ended
	Mar. 31, 2015
Goodwill and Intangible Assets Disclosure [Abstract]
Changes in Carrying Amount of Goodwill	The changes in the carrying amount of goodwill for the three months ended March 31, 2015 are as follows (amounts in thousands):
		Business			Consumer			Total
	Balance as of December 31, 2014	$	72,824		$	8,024		$	80,848
	Adjustments to goodwill:
	Foreign exchange adjustment	(538		)	—			(538		)
	Balance as of March 31, 2015	$	72,286		$	8,024		$	80,310
	The changes in the carrying amount of goodwill for the year ended December 31, 2014 are as follows (amounts in thousands):
		Business			Consumer			Total
	Balance as of December 31, 2013	$	24,700		$	8,024		$	32,724
	Adjustments to goodwill:
	Acquisitions	48,124			—			48,124
	Balance as of December 31, 2014	$	72,824		$	8,024		$	80,848
Summary of Intangible Assets	Intangible assets are summarized as follows (see Note 8) (amounts in thousands):
		As of March 31, 2015
		Gross			Accumulated			Net Carrying Amount			Weighted
		Carrying			Amortization						Average
		Amount									Amortization
											Period
	Amortizing intangible assets:
	Technology	$	28,005		$	(12,379	)	$	15,626		5.3 years
	Customer relationships	16,008			(4,818		)	11,190			7.9 years
	Trade names	1,287			(946		)	341			2.8 years
	Non-compete agreements	1,446			(721		)	725			2.3 years
	Patents	3,290			(584		)	2,706			9.9 years
	Other	312			(271		)	41			3.0 years
	Total	$	50,348		$	(19,719	)	$	30,629
		As of December 31, 2014
		Gross			Accumulated			Net Carrying Amount			Weighted
		Carrying			Amortization						Average
		Amount									Amortization
											Period
	Amortizing intangible assets:
	Technology	$	27,844		$	(11,303	)	$	16,541		5.3 years
	Customer relationships	16,008			(4,055		)	11,953			7.9 years
	Trade names	1,287			(817		)	470			2.8 years
	Non-compete agreements	1,446			(625		)	821			2.3 years
	Patents	3,290			(500		)	2,790			9.9 years
	Other	312			(267		)	45			3.0 years
	Total	$	50,187		$	(17,567	)	$	32,620
Schedule of Finite-Lived Intangible Assets, Future Amortization Expense	Estimated amortization expense for the next five years is as follows (amounts in thousands):
		Estimated Amortization Expense
	2015	$	5,828
	2016	6,755
	2017	4,934
	2018	2,815
	2019	2,809
	Thereafter	7,488
	Total	$	30,629

Property_and_Equipment_Tables

Property and Equipment (Tables)	3 Months Ended
	Mar. 31, 2015
Property, Plant and Equipment [Abstract]
Summary of Property and Equipment	The following table presents the detail of property and equipment for the periods presented (amounts in thousands):
		March 31,			December 31,
		2015			2014
	Computer equipment and software	$	59,122		$	55,293
	Furniture, equipment and building improvements	9,578			9,439
		68,700			64,732
	Less: accumulated depreciation	(47,727		)	(45,149		)
	Total	$	20,973		$	19,583

Accrued_Liabilities_Tables

Accrued Liabilities (Tables)	3 Months Ended
	Mar. 31, 2015
Payables and Accruals [Abstract]
Accrued Liabilities	The following table presents the detail of accrued and other current liabilities for the periods presented (amounts in thousands):
		March 31,		December 31,
		2015		2014
	Payroll and other employee related costs	$	10,893	$	15,373
	Professional services and consulting and other vendor fees	9,730		9,258
	Sales commissions	1,448		3,268
	Contingent earnout (see Notes 8 and 9)	6,591		6,940
	Other	2,869		2,933
	Total	$	31,531	$	37,772

Acquisitions_Tables

Acquisitions (Tables)	3 Months Ended
	Mar. 31, 2015
Synchronite, LLC [Member]
Business Acquisition [Line Items]
Components of Intangible Assets	The components of the intangible assets are as follows (amounts in thousands):
		Weighted		Amount
		Average Useful
		Life (Months)
	Technology	120		$	1,082
	Trade-name	48		62
	Customer relationships	84		247
	Non-compete agreements	36		60
				$	1,451
Contact At Once! [Member]
Business Acquisition [Line Items]
Purchase Price Preliminary Allocation	Management’s preliminary allocation of the purchase price in connection with the CAO! acquisition is as follows (amounts in thousands):
	Cash	$	480
	Accounts receivable	2,694
	Other currents assets	289
	Property and equipment	231
	Other assets	43
	Intangible assets	20,400
	Goodwill	45,064
		69,201
	Liabilities assumed	(2,203		)
	Total purchase price consideration	$	66,998
Components of Intangible Assets	The components of the intangible assets are as follows (amounts in thousands):
		Weighted		Amount
		Average Useful
		Life (Months)
	Technology	96		$	8,400
	Trade-name	12		500
	Customer relationships	120		10,700
	Non-compete agreements	36		800
				$	20,400

Fair_Value_Measurements_Tables

Fair Value Measurements (Tables)	3 Months Ended
	Mar. 31, 2015
Fair Value Disclosures [Abstract]
Fair Value, Assets Measured 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 March 31, 2015 and December 31, 2014, are summarized as follows (amounts in thousands):
		March 31, 2015												December 31, 2014
		Level 1				Level 2				Level 3		Total		Level 1		Level 2		Level 3		Total
	Assets:
	Cash equivalents:
	Money market funds	$	3,088			$	—			$	—	$	3,088	$	3,987	$	—	$	—	$	3,987
	Total assets	$	3,088			$	—			$	—	$	3,088	$	3,987	$	—	$	—	$	3,987
	Liabilities:
	Contingent earn-out	$	—			$	—			$	6,590	$	6,590	$	—	$	—	$	6,940	$	6,940
	Foreign currency derivative contracts	—				423				—		423		—		—		—		—
	Total liabilities	$	—			$	423			$	6,590	$	7,013	$	—	$	—	$	6,940	$	6,940
Change 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
		31-Mar-15				31-Dec-14
	Balance, Beginning of Period	$	6,940			$	1,660
	Synchronite addition (see Note 8)	—				1,810
	CAO! addition (see Note 8)	—				4,220
	Cash payment	(350		)		(750		)
	Balance, End of Period	$	6,590			$	6,940
Schedule of Derivative Instruments	The following summarizes certain information regarding the Company’s outstanding foreign currency derivative contracts related primarily to intercompany receivables and payables for the periods presented (in thousands):
			31-Mar-15				31-Mar-14
	Notional amount of foreign currency derivative contracts		$	38,236			$	—
	Fair value of foreign currency derivatives contracts		$	423			$	—
Schedule of Derivative Liabilities at Fair Value	The fair value of the Company's derivative instruments are summarized below (in thousands):
					Fair Value of Derivative Instruments
			Balance Sheet Location		31-Mar-15				31-Mar-14
	Derivative Liabilities
	Derivatives not designated as hedging instruments:
	Foreign currency derivatives contracts		Accrued expenses and other liabilities		$	423			$	—
Gain (Losses) on Derivative Instruments Recognized in 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 Income Statement
			Location		31-Mar-15				31-Mar-14
	Foreign currency derivatives contracts		Other expense		$	7			$	—

Stockholders_Equity_Tables

Stockholders' Equity (Tables)	3 Months Ended
	Mar. 31, 2015
Disclosure of Compensation Related Costs, Share-based Payments [Abstract]
Summary of Stock-Based Compensation Expense Related to Employee Stock Options	The following table summarizes stock-based compensation expense related to employee stock options under ASC 718-10 included in Company’s statements of operations for the periods presented (amounts in thousands):
		Three Months Ended
		March 31,
		2015				2014
	Cost of revenue	$	328			$	360
	Sales and marketing expense	595				814
	Product development expense	939				680
	General and administrative expense	932				843
	Total stock based compensation included in costs and expenses	$	2,794			$	2,697
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:
		Three Months Ended
		March 31,
		2015		2014
	Dividend yield	0.00%		0.00%
	Risk-free interest rate	1.30%		1.50%
	Expected life (in years)	5		5
	Historical volatility	49.70%		53.70%
Summary 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			Weighted
					Average
					Exercise Price
	Balance outstanding at December 31, 2014	10,769,149			$	10.95
	Granted	434,550			10.53
	Exercised	(430,533	)		4.03
	Cancelled or expired	(620,425	)		12.38
	Balance outstanding at March 31, 2015	10,152,741			$	11.13		7.31	$	9,027
	Options vested and expected to vest at March 31, 2015	8,600,976			$	11.13		7.01	$	8,766
	Options exercisable at March 31, 2015	4,354,151			$	10.5		5.68	$	7,900
Summary of Status of Nonvested Shares	A summary of the status of the Company’s nonvested shares as of December 31, 2014, and changes during the three months ended March 31, 2015 is as follows:
		Options			Weighted
					Average Grant-
					Date Fair Value
	Nonvested Shares at December 31, 2014	6,032,315			$	5.66
	Granted	434,550			4.64
	Vested	(47,850	)		5.1
	Cancelled or expired	(620,425	)		6.09
	Nonvested Shares at March 31, 2015	5,798,590			$	5.59

Revenue_Recognition_Details

Revenue Recognition (Details)	3 Months Ended
	Mar. 31, 2015
Revenue Recognition, Multiple-deliverable Arrangements [Line Items]
Typical service agreements	12 months
Minimum [Member]
Revenue Recognition, Multiple-deliverable Arrangements [Line Items]
Typical service agreements termination notice period	30 days
Maximum [Member]
Revenue Recognition, Multiple-deliverable Arrangements [Line Items]
Typical service agreements termination notice period	90 days

Net_Loss_Per_Share_Narrative_D

Net Loss Per Share (Narrative) (Details)	3 Months Ended
	Mar. 31, 2015	Mar. 31, 2014
Earnings Per Share [Abstract]
Effect of option to purchase share of common stock on diluted net income per share	10,152,741	9,678,582

Net_Loss_Per_Share_Reconciliat

Net Loss Per Share (Reconciliation of Shares Used in Calculating Basic and Diluted Earnings Per Share) (Details)	3 Months Ended
	Mar. 31, 2015	Mar. 31, 2014
Earnings Per Share [Abstract]
Basic	56,291,383	54,666,535
Effect of assumed exercised options	0	0
Diluted	56,291,383	54,666,535

Segment_Information_Narrative_

Segment Information (Narrative) (Details)	3 Months Ended	12 Months Ended
	Mar. 31, 2015	Dec. 31, 2013
Segment Reporting [Abstract]
Number of operating segments	2
Customer Concentration Risk [Member] | Accounts Receivable [Member]
Concentration Risk [Line Items]
Concentration risk, percentage	16.00%	22.00%

Segment_Information_Summary_of

Segment Information (Summary of Financial Information by Segment) (Details) (USD $)	3 Months Ended
In Thousands, unless otherwise specified	Mar. 31, 2015		Mar. 31, 2014
Revenue
Hosted services – Business	$50,613		$39,680
Hosted services – Consumer	3,696		3,910
Professional services	5,461		4,238
Revenue	59,770		47,828
Cost of revenue	16,254	[1],[2],[3]	11,735	[1],[2],[3]
Sales and marketing	24,294	[1],[3]	18,395	[1],[3]
Amortization of purchased intangibles	1,313		190
Unallocated corporate expenses	19,964		18,450
Operating income (loss)	-2,055		-942
Business [Member]
Revenue
Hosted services – Business	50,613		39,680
Professional services	5,461		4,238
Revenue	56,074		43,918
Cost of revenue	15,617		11,220
Sales and marketing	22,852		16,918
Amortization of purchased intangibles	1,313		190
Operating income (loss)	16,292		15,590
Consumer [Member]
Revenue
Hosted services – Consumer	3,696		3,910
Revenue	3,696		3,910
Cost of revenue	637		515
Sales and marketing	1,442		1,477
Operating income (loss)	1,617		1,918
Corporate [Member]
Revenue
Unallocated corporate expenses	19,964		18,450
Operating income (loss)	($19,964)		($18,450)
[1]	Amounts include depreciation expense as follows: Cost of revenue $1,732 and $1,445 for the three months ended September 30, 2014 and 2013, respectively and $4,776 and $4,565 for the nine months ended September 30, 2014 and 2013, respectively, Sales and marketing $195 and $23 for the three months ended September 30, 2014 and 2013, respectively and $603 and $68 for the nine months ended September 30, 2014 and 2013, respectively, Product development $180 and $166 for the three months ended September 30, 2014 and 2013, respectively and $529 and $526 for the nine months ended September 30, 2014 and 2013, respectively, and General and administrative $237 and $368 for the three months ended September 30, 2014 and 2013, respectively and $651 and $891 for the nine months ended September 30, 2014 and 2013, respectively.
[2]	3) Amounts include amortization expense as follows: Cost of revenue $1,732 and $1,445 for the three months ended March 31, 2015 and 2014, respectively.
[3]	Amounts include stock compensation expense as follows: Cost of revenue $365 and $635 for the three months ended September 30, 2014 and 2013, respectively and $1209 and $1557 for the nine months ended September 30, 2014 and 2013, respectively, Sales and marketing $1030 and $844 for the three months ended September 30, 2014 and 2013, respectively and $2,766 and $2,159 for the nine months ended September 30, 2014 and 2013, respectively, Product development $1,171 and $1,241 for the three months ended September 30, 2014 and 2013, respectively and $2,783 and $2,922 for the nine months ended September 30, 2014 and 2013, respectively, and General and administrative $1,088 and $1,078 for the three months ended September 30, 2014 and 2013, respectively and $2,800 and $3,111 for the nine months ended September 30, 2014 and 2013, respectively.

Segment_Information_Revenues_A

Segment Information (Revenues Attributable to Domestic and Foreign Operations) (Details) (USD $)	3 Months Ended
In Thousands, unless otherwise specified	Mar. 31, 2015		Mar. 31, 2014
Segment Reporting Information [Line Items]
Revenue	$59,770		$47,828
United States [Member]
Segment Reporting Information [Line Items]
Revenue	41,442		31,098
Other Americas [Member]
Segment Reporting Information [Line Items]
Revenue	2,703	[1]	2,150	[1]
Americas [Member]
Segment Reporting Information [Line Items]
Revenue	44,145		33,248
EMEA [Member]
Segment Reporting Information [Line Items]
Revenue	11,784	[2]	10,515	[2]
APAC [Member]
Segment Reporting Information [Line Items]
Revenue	$3,841	[3]	$4,065	[3]
[1]	Canada, Latin America and South America
[2]	Europe, the Middle East and Africa (“EMEA”)
[3]	Asia-Pacific (“APAC”)

Segment_Information_LongLived_

Segment Information (Long-Lived Assets by Geographic Region) (Details) (USD $)	Mar. 31, 2015	Dec. 31, 2014
In Thousands, unless otherwise specified
Segment Reporting Information [Line Items]
Total long-lived assets	$145,509	$146,114
United States [Member]
Segment Reporting Information [Line Items]
Total long-lived assets	109,517	109,006
Israel [Member]
Segment Reporting Information [Line Items]
Total long-lived assets	18,173	18,982
Australia [Member]
Segment Reporting Information [Line Items]
Total long-lived assets	8,132	8,500
Netherlands [Member]
Segment Reporting Information [Line Items]
Total long-lived assets	7,709	7,686
United Kingdom [Member]
Segment Reporting Information [Line Items]
Total long-lived assets	$1,978	$1,940

Goodwill_and_Intangible_Assets2

Goodwill and Intangible Assets (Narrative) (Details) (USD $)	3 Months Ended
In Thousands, unless otherwise specified	Mar. 31, 2015	Mar. 31, 2014
Goodwill and Intangible Assets Disclosure [Abstract]
Aggregate amortization expense for intangible assets	$2,152	$1,058

Goodwill_and_Intangible_Assets3

Goodwill and Intangible Assets (Changes in Carrying Amount of Goodwill) (Details) (USD $)	12 Months Ended	3 Months Ended
In Thousands, unless otherwise specified	Dec. 31, 2014	Mar. 31, 2015	Dec. 31, 2013
Goodwill [Line Items]
Beginning Balance	$32,724
Goodwill Acquisitions	48,124
Ending Balance	80,848	80,310
Business [Member]
Goodwill [Line Items]
Beginning Balance	24,700
Goodwill Acquisitions	48,124
Ending Balance	72,824	72,286
Consumer [Member]
Goodwill [Line Items]
Beginning Balance			8,024
Ending Balance	8,024	8,024	8,024
Synchronite, LLC [Member]
Goodwill [Line Items]
Goodwill, Translation Adjustments		-538
Ending Balance		2,700
Synchronite, LLC [Member] | Business [Member]
Goodwill [Line Items]
Goodwill, Translation Adjustments		($538)

Goodwill_and_Intangible_Assets4

Goodwill and Intangible Assets (Summary of Intangible Assets) (Details) (USD $)	3 Months Ended		12 Months Ended
In Thousands, unless otherwise specified	Mar. 31, 2015	Mar. 31, 2014	Dec. 31, 2014
Acquired Finite-Lived Intangible Assets [Line Items]
Gross Carrying Amount	$50,348	$50,187
Accumulated Amortization	-19,719		-17,567
Intangibles, net	30,629		32,620
Technology [Member]
Acquired Finite-Lived Intangible Assets [Line Items]
Gross Carrying Amount	28,005	27,844
Accumulated Amortization	-12,379		-11,303
Intangibles, net	15,626		16,541
Weighted Average Amortization Period	5 years 3 months 18 days		5 years 3 months 18 days
Customer relationships [Member]
Acquired Finite-Lived Intangible Assets [Line Items]
Gross Carrying Amount	16,008	16,008
Accumulated Amortization	-4,818		-4,055
Intangibles, net	11,190		11,953
Weighted Average Amortization Period	7 years 10 months 18 days		7 years 10 months 18 days
Trade names [Member]
Acquired Finite-Lived Intangible Assets [Line Items]
Gross Carrying Amount	1,287	1,287
Accumulated Amortization	-946		-817
Intangibles, net	341		470
Weighted Average Amortization Period	2 years 9 months 12 days		2 years 9 months 12 days
Non-compete agreements [Member]
Acquired Finite-Lived Intangible Assets [Line Items]
Gross Carrying Amount	1,446	1,446
Accumulated Amortization	-721		-625
Intangibles, net	725		821
Weighted Average Amortization Period	2 years 3 months 12 days		2 years 3 months 12 days
Patents [Member]
Acquired Finite-Lived Intangible Assets [Line Items]
Gross Carrying Amount	3,290	3,290
Accumulated Amortization	-584		-500
Intangibles, net	2,706		2,790
Weighted Average Amortization Period	9 years 10 months 18 days		9 years 10 months 18 days
Other [Member]
Acquired Finite-Lived Intangible Assets [Line Items]
Gross Carrying Amount	312	312
Accumulated Amortization	-271		-267
Intangibles, net	$41		$45
Weighted Average Amortization Period	3 years		3 years

Goodwill_and_Intangible_Assets5

Goodwill and Intangible Assets (Future Amortization Expense) (Details) (USD $)	Mar. 31, 2015
In Thousands, unless otherwise specified
Goodwill and Intangible Assets Disclosure [Abstract]
2015	$5,828
2016	6,755
2017	4,934
2018	2,815
2019	2,809
Thereafter	7,488
Total	$30,629

Property_and_Equipment_Details

Property and Equipment (Details) (USD $)	Mar. 31, 2015	Dec. 31, 2014
In Thousands, unless otherwise specified
Property, Plant and Equipment [Line Items]
Property plant and equipment gross	$68,700	$64,732
Less: accumulated depreciation	-47,727	-45,149
Total	20,973	19,583
Computer Equipment And Software [Member]
Property, Plant and Equipment [Line Items]
Property plant and equipment gross	59,122	55,293
Furniture, Equipment and Building Improvements [Member]
Property, Plant and Equipment [Line Items]
Property plant and equipment gross	$9,578	$9,439

Accrued_Liabilities_Details

Accrued Liabilities (Details) (USD $)	Mar. 31, 2015	Dec. 31, 2014
In Thousands, unless otherwise specified
Payables and Accruals [Abstract]
Payroll and other employee related costs	$10,893	$15,373
Professional services and consulting and other vendor fees	9,730	9,258
Sales commissions	1,448	3,268
Contingent earnout (see Notes 8 and 9)	6,591	6,940
Other	2,869	2,933
Total	$31,531	$37,772

Acquisitions_Narrative_Details

Acquisitions (Narrative) (Details) (USD $)	0 Months Ended	12 Months Ended	1 Months Ended	0 Months Ended	3 Months Ended	0 Months Ended
	Nov. 09, 2012	Dec. 31, 2013	Mar. 31, 2014	Jun. 02, 2014	Mar. 31, 2015	Nov. 07, 2014	Nov. 08, 2014	Dec. 31, 2014
Business Acquisition [Line Items]
Goodwill		$32,724,000			$80,310,000			$80,848,000
Engage Pty Ltd. [Member]
Business Acquisition [Line Items]
Business acquisition, acquisition date	9-Nov-12
Acquisition costs incurred to acquire entity		500,000
Assets acquired liabilities assumed, net	800,000
Potential earn-out consideration	1,700,000				300,000
Engage [Member]
Business Acquisition [Line Items]
Total consideration transferred	10,600,000
NexGraph, LLC [Member]
Business Acquisition [Line Items]
Business acquisition, acquisition date			11-Mar-14
Acquired Intangible Assets Amount			500,000
Intangible assets			100,000
Goodwill			400,000
Synchronite, LLC [Member]
Business Acquisition [Line Items]
Business acquisition, acquisition date				2-Jun-14
Total consideration transferred				4,100,000
Acquisition costs incurred to acquire entity					400,000
Assets acquired liabilities assumed, net				45,000
Potential earn-out consideration				1,800,000
Intangible assets				1,451,000	1,450,000
Goodwill					2,700,000
Contact At Once! [Member]
Business Acquisition [Line Items]
Business acquisition, acquisition date						7-Nov-14
Total consideration transferred							67,000,000
Acquired intangible asset, aggregate cash consideration						66,998,000
Potential earn-out consideration						4,200,000
Intangible assets						20,400,000
Goodwill						45,064,000
Cash payment						42,800,000
Consideration transferred, shares						$20,000,000

Acquisitions_Purchase_Price_Pr

Acquisitions (Purchase Price Preliminary Allocation) (Details) (USD $)	Mar. 31, 2015	Dec. 31, 2014	Dec. 31, 2013	Nov. 07, 2014
In Thousands, unless otherwise specified
Business Acquisition [Line Items]
Goodwill	$80,310	$80,848	$32,724
Contact At Once! [Member]
Business Acquisition [Line Items]
Cash				480
Accounts receivable				2,694
Other currents assets				289
Property and equipment				231
Other assets				43
Intangible assets				20,400
Goodwill				45,064
Total assets				69,201
Liabilities assumed				-2,203
Total purchase price consideration				$66,998

Acquisitions_Components_of_Int

Acquisitions (Components of Intangible Assets) (Details) (USD $)	3 Months Ended	12 Months Ended	0 Months Ended
In Thousands, unless otherwise specified	Mar. 31, 2015	Dec. 31, 2014	Nov. 07, 2014	Jun. 02, 2014
Contact At Once! [Member]
Business Acquisition [Line Items]
Intangible assets			$20,400
Synchronite, LLC [Member]
Business Acquisition [Line Items]
Intangible assets	1,450			1,451
Technology [Member]
Business Acquisition [Line Items]
Weighted average useful life	5 years 3 months 18 days	5 years 3 months 18 days
Technology [Member] | Contact At Once! [Member]
Business Acquisition [Line Items]
Weighted average useful life			96 months
Intangible assets			8,400
Technology [Member] | Synchronite, LLC [Member]
Business Acquisition [Line Items]
Weighted average useful life				120 months
Intangible assets				1,082
Trade Names [Member]
Business Acquisition [Line Items]
Weighted average useful life	2 years 9 months 12 days	2 years 9 months 12 days
Trade Names [Member] | Contact At Once! [Member]
Business Acquisition [Line Items]
Weighted average useful life			12 months
Intangible assets			500
Trade Names [Member] | Synchronite, LLC [Member]
Business Acquisition [Line Items]
Weighted average useful life				48 months
Intangible assets				62
Customer Relationships [Member] | Contact At Once! [Member]
Business Acquisition [Line Items]
Weighted average useful life			120 months
Intangible assets			10,700
Customer Relationships [Member] | Synchronite, LLC [Member]
Business Acquisition [Line Items]
Weighted average useful life				84 months
Intangible assets				247
Non-compete Agreements [Member]
Business Acquisition [Line Items]
Weighted average useful life	2 years 3 months 12 days	2 years 3 months 12 days
Non-compete Agreements [Member] | Contact At Once! [Member]
Business Acquisition [Line Items]
Weighted average useful life			36 months
Intangible assets			800
Non-compete Agreements [Member] | Synchronite, LLC [Member]
Business Acquisition [Line Items]
Weighted average useful life				36 months
Intangible assets				$60

Fair_Value_Measurements_Detail

Fair Value Measurements (Details) (Recurring [Member], USD $)	3 Months Ended	12 Months Ended	0 Months Ended
In Thousands, unless otherwise specified	Mar. 31, 2015	Dec. 31, 2014	Jun. 02, 2014	Nov. 07, 2014
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Assets, Fair Value Disclosure	$3,088	$3,987
Liabilities, Fair Value Disclosure	7,013	6,940
Level 1 [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Assets, Fair Value Disclosure	3,088	3,987
Level 2 [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Liabilities, Fair Value Disclosure	423	0
Level 3 [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Liabilities, Fair Value Disclosure	6,590	6,940
Money Market Funds [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Assets, Fair Value Disclosure	3,088	3,987
Money Market Funds [Member] | Level 1 [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Assets, Fair Value Disclosure	3,088	3,987
Contingent Earn-Out [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Liabilities, Fair Value Disclosure	6,590	6,940
Contingent Earn-Out [Member] | Level 3 [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Liabilities, Fair Value Disclosure	6,590	6,940
Foreign Currency Derivatives Contracts [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Liabilities, Fair Value Disclosure	423	0
Foreign Currency Derivatives Contracts [Member] | Level 2 [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Liabilities, Fair Value Disclosure	423	0
Engage [Member] | Contingent Earn-Out [Member] | Level 3 [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Liabilities, Fair Value Disclosure	700	900
Synchronite, LLC [Member] | Level 3 [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Change in contingent consideration	0	1,810
Synchronite, LLC [Member] | Contingent Earn-Out [Member] | Level 3 [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Change in contingent consideration			1,800
Contact At Once! [Member] | Level 3 [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Change in contingent consideration	0	4,220
Contact At Once! [Member] | Contingent Earn-Out [Member] | Level 3 [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Change in contingent consideration				$4,200

Fair_Value_Measurements_Level_

Fair Value Measurements Level 3 Liabilities (Details) (USD $)	3 Months Ended	12 Months Ended	0 Months Ended
In Thousands, unless otherwise specified	Mar. 31, 2015	Dec. 31, 2014	Jun. 02, 2014	Nov. 07, 2014
Recurring [Member] | Level 3 [Member]
Business Combination, Contingent Consideration Arrangements, Change In Contingent Consideration Liability [Roll Forward]
Balance, Beginning of Period	$6,940	$1,660
Cash payment	-350	-750
Balance, End of Period	6,590	6,940
Synchronite, LLC [Member]
Business Combination, Contingent Consideration Arrangements, Change In Contingent Consideration Liability [Roll Forward]
Balance, End of Period			1,800
Synchronite, LLC [Member] | Recurring [Member] | Level 3 [Member]
Business Combination, Contingent Consideration Arrangements, Change In Contingent Consideration Liability [Roll Forward]
Synchronite addition	0	1,810
Contact At Once! [Member]
Business Combination, Contingent Consideration Arrangements, Change In Contingent Consideration Liability [Roll Forward]
Balance, Beginning of Period				4,200
Balance, End of Period				4,200
Contact At Once! [Member] | Recurring [Member] | Level 3 [Member]
Business Combination, Contingent Consideration Arrangements, Change In Contingent Consideration Liability [Roll Forward]
Synchronite addition	0	4,220
Contingent Earn-Out [Member] | Synchronite, LLC [Member] | Recurring [Member] | Level 3 [Member]
Business Combination, Contingent Consideration Arrangements, Change In Contingent Consideration Liability [Roll Forward]
Synchronite addition			1,800
Contingent Earn-Out [Member] | Contact At Once! [Member] | Recurring [Member] | Level 3 [Member]
Business Combination, Contingent Consideration Arrangements, Change In Contingent Consideration Liability [Roll Forward]
Synchronite addition				$4,200

Fair_Value_Measurements_Deriva

Fair Value Measurements Derivative Financial Instruments (Details) (Foreign Currency Derivatives Contracts [Member], USD $)	3 Months Ended
In Thousands, unless otherwise specified	Mar. 31, 2015	Mar. 31, 2014	Dec. 31, 2014
Derivative [Line Items]
Notional amount	$38,236		$0
Fair value	423		0
Accrued Expenses And Other Liabilities [Member] | Not Designated as Hedging Instrument [Member]
Derivative [Line Items]
Derivative liabilities	423		0
Other Expense [Member]
Derivative [Line Items]
Gain (losses) on derivative instruments	$7	$0

Commitments_and_Contingencies_

Commitments and Contingencies (Details) (USD $)	3 Months Ended
	Mar. 31, 2015	Mar. 31, 2014
Commitments and Contingencies Disclosure [Abstract]
Rental expense for operating leases	$2,500,000	$2,200,000
Defined benefit plan employer matching contribution on first five percent of employee compensation	50.00%
Percentage of employees' eligible compensation for employer matching contribution	5.00%
Defined benefit plan employer contribution limit	6,000
Defined benefit plan employer contribution vesting period	5 years
Defined benefit plan employer contribution	$400,000	$300,000

Stockholders_Equity_Narrative_

Stockholders' Equity (Narrative) (Details) (USD $)	3 Months Ended
	Mar. 31, 2015	Mar. 31, 2014	Dec. 31, 2014	Jun. 30, 2010	Jul. 23, 2014	Mar. 13, 2014	Dec. 10, 2012
Common Stock, Number of Shares, Par Value and Other Disclosures [Abstract]
Common stock, shares authorized	100,000,000		100,000,000
Common stock, shares issued (in shares)	57,039,125		56,701,331
Common stock, shares outstanding (in shares)	54,584,170		54,484,760
Common stock, par value (in dollars per share)	$0.00		$0.00
Preferred Stock, Number of Shares, Par Value and Other Disclosures [Abstract]
Preferred stock, shares authorized	5,000,000		5,000,000
Preferred stock, shares issued (in shares)	0		0
Preferred stock, shares outstanding (in shares)	0		0
Preferred stock, par value (in dollars per share)	$0.00		$0.00
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Sharebased Compensation Arrangement By Sharebased Payment Award Options Nonvested Aggregate Intrinsic Value	$1,100,000
Treasury Stock, Shares	33,360
Weighted average fair value of stock options granted	$4.64	$6.25
Dividend yield	0.00%	0.00%
Share-based Compensation Arrangement by Share-based Payment Award, Fair Value Assumptions, Expected Term	5 years	5 years
Share-based Compensation Arrangement By Share-based Payment Award, Fair Value Assumptions, Period Used To Determine Volatility	5 years
Stock option term	10 years
Total value of stock options exercised	1,100,000
Incentive Stock Option [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Unrecognized compensation cost related to nonvested share-based compensation arrangements	25,600,000
Weighted average recognition period of unrecognized compensation cost	2 years 7 months 6 days
1998 Plan [Member] | Incentive Stock Option [Member] | Maximum [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Shares of common stock available for issuance	5,850,000
2000 Plan [Member] | Incentive Stock Option [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Increase in number of shares of common stock available for issuance	4,150,000
1998 and 2000 Plan [Member] | Incentive Stock Option [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Shares of common stock available for issuance	10,000,000
2009 Plan [Member] | Incentive Stock Option [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Shares of common stock available for issuance	13,100,000
Increase in number of shares of common stock available for issuance	6,000,000
2010 Employee Stock Purchase Plan [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Shares of common stock available for issuance	519,000			1,000,000
2009 Plan [Member] | 2009 Plan [Member] | Incentive Stock Option [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Shares of common stock available for issuance	23,817,744
Increase in number of shares of common stock available for issuance	4,250,000
2012 Stock Repurchase Program [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Stock repurchase program, authorized amount					50,000,000	40,000,000	30,000,000
Stock repurchased during period, shares	176,172
Stock repurchase program, remaining authorized repurchase amount	$8,200,000

Stockholders_Equity_Summary_of

Stockholders' Equity (Summary of Stock-Based Compensation Expense Related to Employee Stock Options) (Details) (USD $)	3 Months Ended
In Thousands, unless otherwise specified	Mar. 31, 2015	Mar. 31, 2014
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Stock-based compensation expense	$2,794	$2,697
Cost of revenue [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Stock-based compensation expense	328	360
Sales and marketing expense [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Stock-based compensation expense	595	814
Product development expense [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Stock-based compensation expense	939	680
General and administrative expense [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Stock-based compensation expense	$932	$843

Stockholders_Equity_Weighted_A

Stockholders' Equity (Weighted Average Assumptions of Fair Value Options Using Black-Scholes Option-Pricing Model) (Details)	3 Months Ended
	Mar. 31, 2015	Mar. 31, 2014
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Dividend yield	0.00%	0.00%
Risk-free interest rate	1.30%	1.50%
Expected life (in years)	5 years	5 years
Historical volatility	49.70%	53.70%

Stockholders_Equity_Summary_of1

Stockholders' Equity (Summary of Stock Option Activity and Weighted Average Exercise Prices) (Details) (USD $)	3 Months Ended
In Thousands, except Share data, unless otherwise specified	Mar. 31, 2015
Options
Options outstanding at December 31, 2014	10,769,149
Options granted	434,550
Options exercised	-430,533
Options cancelled	-620,425
Options outstanding at March 31, 2015	10,152,741
Options vested and expected to vest at March 31, 2015	8,600,976
Options exercisable at March 31, 2015	4,354,151
Weighted Average Exercise Price
Options outstanding at December 31, 2013	$10.95
Options granted	$10.53
Options exercised	$4.03
Options cancelled	$12.38
Options outstanding at March 31, 2015	$11.13
Options vested and expected to vest at March 31, 2015	$11.13
Options exercisable at March 31, 2015	$10.50
Weighted Average Remaining Contractual Term (in years)
Options outstanding at March 31, 2015	7 years 3 months 22 days
Options vested and expected to vest at March 31, 2015	7 years 0 months 4 days
Options exercisable at March 31, 2015	5 years 8 months 5 days
Aggregate Intrinsic Value
Options outstanding at March 31, 2015	$9,027
Options vested and expected to vest at March 31, 2015	8,766
Options exercisable at March 31, 2015	$7,900

Stockholders_Equity_Summary_of2

Stockholders' Equity (Summary of Status of Nonvested Shares) (Details) (USD $)	3 Months Ended
	Mar. 31, 2015
Shares
Nonvested Shares at December 31, 2014	6,032,315
Granted	434,550
Vested	-47,850
Cancelled or expired	-620,425
Nonvested Shares at March 31, 2015	5,798,590
Weighted Average Grant-Date Fair Value
Nonvested Shares at December 31, 2014	$5.66
Granted	$4.64
Vested	$5.10
Cancelled or expired	$6.09
Nonvested Shares at March 31, 2015	$5.59