Constant Contact (CTCT) 10-Q 7 May 14 2014 Q1 Quarterly report Financial data

Document_and_Entity_Informatio

Document and Entity Information	3 Months Ended
	Mar. 31, 2014	2-May-14
Document And Entity Information [Abstract]	'	'
Document Type	'10-Q	'
Amendment Flag	'false	'
Document Period End Date	31-Mar-14	'
Document Fiscal Year Focus	'2014	'
Document Fiscal Period Focus	'Q1	'
Trading Symbol	'CTCT	'
Entity Registrant Name	'CONSTANT CONTACT, INC.	'
Entity Central Index Key	'0001405277	'
Current Fiscal Year End Date	'--12-31	'
Entity Filer Category	'Accelerated Filer	'
Entity Common Stock, Shares Outstanding	'	31,390,030

Condensed_Consolidated_Balance

Condensed Consolidated Balance Sheets (USD $)	Mar. 31, 2014	Dec. 31, 2013
In Thousands, unless otherwise specified
Current assets	'	'
Cash and cash equivalents	$87,059	$82,478
Marketable securities	43,760	40,723
Accounts receivable, net of allowance for doubtful accounts	136	180
Prepaid expenses and other current assets	10,843	9,175
Total current assets	141,798	132,556
Property and equipment, net	39,873	39,238
Restricted cash	1,300	1,300
Goodwill	95,505	95,505
Acquired intangible assets, net	3,788	4,355
Deferred taxes	9,574	9,574
Other assets	2,358	2,345
Total assets	294,196	284,873
Current liabilities	'	'
Accounts payable	6,519	6,783
Accrued expenses	11,967	10,903
Deferred revenue	37,326	35,256
Total current liabilities	55,812	52,942
Other long-term liabilities	1,962	2,060
Total liabilities	57,774	55,002
Commitments and contingencies (Note 7)	'	'
Stockholders' equity	'	'
Preferred stock; $0.01 par value; 5,000,000 shares authorized; no shares issued or outstanding at March 31, 2014 and December 31, 2013	'	'
Common stock; $0.01 par value; 100,000,000 shares authorized; 31,368,389 and 31,203,585 shares issued and outstanding at March 31, 2014 and December 31, 2013, respectively	314	312
Additional paid-in capital	235,160	229,457
Accumulated other comprehensive income	12	14
Retained earnings	936	88
Total stockholders' equity	236,422	229,871
Total liabilities and stockholders' equity	$294,196	$284,873

Condensed_Consolidated_Balance1

Condensed Consolidated Balance Sheets (Parenthetical) (USD $)	Mar. 31, 2014	Dec. 31, 2013
Statement Of Financial Position [Abstract]	'	'
Preferred stock, par value	$0.01	$0.01
Preferred stock, shares authorized	5,000,000	5,000,000
Preferred stock, shares issued	0	0
Preferred stock, shares outstanding	0	0
Common stock, par value	$0.01	$0.01
Common stock, shares authorized	100,000,000	100,000,000
Common stock, shares issued	31,368,389	31,203,585
Common stock, shares outstanding	31,368,389	31,203,585

Condensed_Consolidated_Stateme

Condensed Consolidated Statements of Operations (USD $)	3 Months Ended
In Thousands, except Per Share data, unless otherwise specified	Mar. 31, 2014	Mar. 31, 2013
Income Statement [Abstract]	'	'
Revenue	$78,874	$68,205
Cost of revenue	21,727	19,908
Gross profit	57,147	48,297
Operating expenses:	'	'
Research and development	13,074	10,268
Sales and marketing	32,800	30,802
General and administrative	10,120	9,840
Total operating expenses	55,994	50,910
Income (loss) from operations	1,153	-2,613
Interest and other income (expense), net	23	-29
Income (loss) before income taxes	1,176	-2,642
Income tax (expense) benefit	-328	1,988
Net income (loss)	$848	($654)
Net income (loss) per share:	'	'
Basic	$0.03	($0.02)
Diluted	$0.03	($0.02)
Weighted average shares outstanding used in computing per share amounts:	'	'
Basic	31,289	30,630
Diluted	32,442	30,630

Condensed_Consolidated_Stateme1

Condensed Consolidated Statements of Comprehensive Income (Loss) (USD $)	3 Months Ended
In Thousands, unless otherwise specified	Mar. 31, 2014	Mar. 31, 2013
Statement Of Income And Comprehensive Income [Abstract]	'	'
Net income (loss)	$848	($654)
Other comprehensive loss:	'	'
Net unrealized gains (losses) on marketable securities	-3	3
Translation adjustment	1	-4
Total other comprehensive loss	-2	-1
Comprehensive income (loss)	$846	($655)

Condensed_Consolidated_Stateme2

Condensed Consolidated Statements of Cash Flows (USD $)	3 Months Ended
In Thousands, unless otherwise specified	Mar. 31, 2014	Mar. 31, 2013
Cash flows from operating activities	'	'
Net income (loss)	$848	($654)
Adjustments to reconcile net income (loss) to net cash provided by operating activities:	'	'
Depreciation and amortization	5,911	5,115
Amortization of premiums on investments	55	70
Stock-based compensation expense	3,914	3,541
Provision for (recovery of) bad debts	5	-2
Deferred income taxes	'	-1,988
Income tax benefit from the exercise of stock options	-226	-6
Taxes paid related to net share settlement of restricted stock units	-751	-285
Changes in operating assets and liabilities, net of effects from acquisition:	'	'
Accounts receivable	39	25
Prepaid expenses and other current assets	-1,463	-3,186
Other assets	-13	157
Accounts payable	-264	-1,300
Accrued expenses	1,064	5,360
Deferred revenue	2,070	2,101
Other long-term liabilities	-98	60
Net cash provided by operating activities	11,091	9,008
Cash flows from investing activities	'	'
Purchases of marketable securities	-15,963	-1,909
Proceeds from maturities of marketable securities	12,865	8,634
Proceeds from sales of marketable securities	'	4,000
Increase in restricted cash	'	-550
Acquisition of property and equipment, including costs capitalized for development of internal use software	-5,929	-4,744
Net cash provided by (used in) investing activities	-9,027	5,431
Cash flows from financing activities	'	'
Proceeds from issuance of common stock pursuant to the exercise of stock options	2,290	182
Income tax benefit from the exercise of stock options	226	6
Net cash provided by financing activities	2,516	188
Effects of exchange rates on cash	1	-2
Net increase in cash and cash equivalents	4,581	14,625
Cash and cash equivalents, beginning of period	82,478	67,775
Cash and cash equivalents, end of period	87,059	82,400
Supplemental disclosure of noncash investing activities:	'	'
Capitalization of stock-based compensation	$50	$166

Nature_of_the_Business

Nature of the Business	3 Months Ended
	Mar. 31, 2014
Accounting Policies [Abstract]	'
Nature of the Business	'
	1. Nature of the Business
	Constant Contact, Inc. (the “Company”) was incorporated as a Massachusetts corporation in 1995 and was reincorporated in the State of Delaware in 2000. The Company is a leading provider of online marketing tools that are designed for small organizations, including small businesses, associations and non-profits. The Company seeks to help customers succeed by creating and growing their customer and member relationships through easy-to-use products combined with education, support, KnowHow® and coaching. The Company’s suite of online marketing tools, which include Email Marketing, EventSpot®, Social Campaigns™, SaveLocal™, SinglePlatform and Survey, enable customers to launch and monitor marketing campaigns across multiple channels, including email, social media, events, local deals, online listings and surveys. These products are marketed and sold directly by the Company and through a wide variety of partners primarily in the United States of America.

Summary_of_Significant_Account

Summary of Significant Accounting Policies	3 Months Ended
	Mar. 31, 2014
Accounting Policies [Abstract]	'
Summary of Significant Accounting Policies	'
	2. Summary of Significant Accounting Policies
	Basis of Presentation
	The accompanying consolidated financial statements include those of the Company and its subsidiaries, after elimination of all intercompany accounts and transactions. The accompanying consolidated financial statements have been prepared in conformity with accounting principles generally accepted in the United States of America (“GAAP”).
	The condensed consolidated balance sheet at December 31, 2013 was derived from audited financial statements, but does not include all disclosures required by GAAP. The accompanying unaudited condensed consolidated financial statements as of March 31, 2014 and for the three months ended March 31, 2014 and 2013 have been prepared by the Company, pursuant to the rules and regulations of the Securities and Exchange Commission (“SEC”) for interim financial statements. Certain information and footnote disclosures normally included in financial statements prepared in accordance with GAAP have been condensed or omitted pursuant to such rules and regulations. However, the Company believes that the disclosures are adequate to make the information presented not misleading. These condensed consolidated financial statements should be read in conjunction with the Company’s audited consolidated financial statements and the notes thereto for the year ended December 31, 2013 included in the Company’s Annual Report on Form 10-K, File Number 001-33707, on file with the SEC.
	In the opinion of management, all adjustments, consisting only of normal recurring adjustments necessary for a fair statement of the Company’s consolidated financial position as of March 31, 2014 and consolidated results of operations for the three months ended March 31, 2014 and 2013 and consolidated cash flows for the three months ended March 31, 2014 and 2013 have been made. The results of operations for the three months ended March 31, 2014 are not necessarily indicative of the results of operations that may be expected for the year ending December 31, 2014.
	Use of Estimates
	The preparation of financial statements in conformity with GAAP requires management to make estimates and assumptions that affect the reported amounts of assets and liabilities and the disclosure of contingent assets and liabilities at the date of the financial statements and the reported amounts of revenue and expenses during the reporting period. On an ongoing basis, management evaluates these estimates, judgments and assumptions, including those related to revenue recognition, stock-based compensation, goodwill and acquired intangible assets, capitalization of software and website development costs, liability for contingent consideration, litigation accruals and income taxes. The Company bases these estimates on historical and anticipated results and trends and on various other assumptions that the Company believes are reasonable under the circumstances, including assumptions as to future events. These estimates form the basis for making judgments about the carrying values of assets and liabilities and recorded revenue and expenses that are not readily apparent from other sources. Actual results could differ from these estimates.
	Revenue Recognition
	The Company provides access to its products primarily through subscription arrangements whereby the customer is charged a fee for access for a defined term. Subscription arrangements include access to use the Company’s software via the Internet and support services, such as telephone, email and chat support. When there is evidence of an arrangement, the fee is fixed or determinable and collectability is deemed reasonably assured, the Company recognizes revenue on a daily basis over the subscription period as the services are delivered. Delivery is considered to have commenced at the time the customer has paid for the products and has access to the account via a log-in and password. The Company generates revenue from its SaveLocal product by charging a fee to its customers based on the number of deals sold by its customers and the value of the successful deal. The Company recognizes revenue from the fee charged when there is evidence of an arrangement, the fee is fixed or determinable and collectability is deemed reasonably assured. The Company also offers ancillary services to its customers related to its subscription-based products such as custom services and training. When sold together, revenue from custom services, training and subscription products are accounted for separately based on vendor-specific objective evidence of fair value of each of the services as those services have value on a standalone basis and do not involve a significant degree of risk or unique acceptance criteria. Revenue from custom services and training is recognized as the services are performed.
	Deferred Revenue
	Deferred revenue consists of payments received in advance of delivery of the Company’s products described above and is recognized as the revenue recognition criteria are met. The Company’s customers generally pay for services in advance on a monthly, semiannual or annual basis.
	Accounts Receivable
	Management reviews accounts receivable on a periodic basis to determine if any receivables will potentially be uncollectible. The Company reserves for receivables that are determined to be uncollectible, if any, in its allowance for doubtful accounts. After the Company has exhausted all collection efforts, the outstanding receivable is written off against the allowance.
	Concentration of Credit Risk and Significant Products and Customers
	Financial instruments that potentially expose the Company to concentrations of credit risk consist primarily of cash, cash equivalents and marketable securities. As of March 31, 2014 and December 31, 2013, the Company had substantially all cash and investment balances at certain financial institutions without or in excess of federally insured limits, however, the Company maintains its cash balances and custody of its marketable securities with accredited financial institutions. The Company does not believe that it is subject to unusual credit risk beyond the normal credit risk associated with commercial banking relationships.
	For the three months ended March 31, 2014 and 2013, revenue from the Company’s email marketing product alone as a percentage of total revenue was approximately 84% and 85%, respectively. No customer accounted for more than 10% of total revenue during these periods.
	Goodwill and Acquired Intangible Assets
	The Company records goodwill when consideration paid in a business acquisition exceeds the fair value of the net tangible assets and the identified intangible assets acquired. Goodwill is not amortized, but rather is tested for impairment annually or more frequently if facts and circumstances warrant a review. The Company performs its annual assessment for impairment of goodwill on November 30th and has determined that there is a single reporting unit for the purpose of conducting this annual goodwill impairment assessment.
	Intangible assets are recorded at their estimated fair values at the date of acquisition. The Company amortizes acquired intangible assets over their estimated useful lives based on the pattern of consumption of the economic benefits or, if that pattern cannot be readily determined, on a straight-line basis.
	Software and Web Site Development Costs
	Research and development costs are expensed as incurred and primarily include salaries, fees to consultants and other related costs. Relative to development costs of its on-demand products and website, the Company capitalizes certain direct costs to develop functionality as well as certain upgrades and enhancements that are probable to result in additional functionality. The costs incurred in the preliminary stages of development are expensed as incurred. Once an application has reached the development stage, internal and external costs, if direct and incremental, are capitalized as part of property and equipment until the software is substantially complete and ready for its intended use. Capitalized software is amortized over a three-year period in the expense category to which the software relates.
	Foreign Currency Translation
	The functional currency of the Company’s UK operations is deemed to be the British pound. Accordingly, the assets and liabilities of the Company’s UK subsidiary are translated into United States dollars using the period-end exchange rate, and income and expense items are translated using the average exchange rate during the period. Cumulative translation adjustments are reflected as a separate component of stockholders’ equity. Foreign currency transaction gains and losses are charged to other income (expense) and were not material to the Company’s operations.
	Comprehensive Income (Loss)
	Comprehensive income (loss) includes net income (loss), as well as other changes in stockholders’ equity that result from transactions and economic events other than those with stockholders. The Company’s only elements of other comprehensive income (loss) are unrealized gains and losses on available-for-sale securities and translation adjustments.
	Cash and Cash Equivalents
	The Company considers all highly liquid investments with original maturities of three months or less at the time of acquisition to be cash equivalents. The Company also considers receivables related to customer credit card purchases of $3,034 and $2,901 as of March 31, 2014 and December 31, 2013, respectively, to be equivalent to cash. Cash equivalents are stated at fair value.
	Marketable Securities
	The Company’s marketable securities are classified as available-for-sale and are carried at fair value with the unrealized gains and losses reported as a component of accumulated other comprehensive income (loss) in stockholders’ equity. Realized gains and losses and declines in value judged to be other than temporary are included as a component of interest and other income (expense) based on the specific identification method.
	At March 31, 2014, marketable securities by security type consisted of:
			Amortized		Gross		Gross			Estimated
			Cost		Unrealized		Unrealized			Fair
					Gains		Losses			Value
	U.S. Treasury Notes		$	20,001	$	16	$	—		$	20,017
	Corporate and Agency Bonds			22,351		7		(12	)		22,346
	Commercial Paper			1,397		—		—			1,397
	Total		$	43,749	$	23	$	(12	)	$	43,760
	At March 31, 2014, marketable securities consisted of investments that mature within one year with the exception of government treasuries and corporate and agency bonds with a fair value of $21,964, which have maturities within two years.
	At December 31, 2013, marketable securities by security type consisted of:
			Amortized		Gross		Gross			Estimated
			Cost		Unrealized		Unrealized			Fair
					Gains		Losses			Value
	U.S. Treasury Notes		$	27,022	$	13	$	—		$	27,035
	Corporate and Agency Bonds			12,684		4		—			12,688
	Commercial Paper			1,000		—		—			1,000
	Total		$	40,706	$	17	$	—		$	40,723
	Fair Value of Financial Instruments
	Certain assets and liabilities are carried at fair value under GAAP. Fair value is defined as the exchange price that would be received for an asset or paid to transfer a liability (an exit price) in the principal or most advantageous market for the asset or liability in an orderly transaction between market participants on the measurement date. Valuation techniques used to measure fair value must maximize the use of observable inputs and minimize the use of unobservable inputs. A fair value hierarchy based on three levels of inputs, of which the first two are considered observable and the last is considered unobservable, is used to measure fair value:
		•		Level 1 — Quoted prices in active markets for identical assets or liabilities.
		•		Level 2 — Inputs other than Level 1 that are observable, either directly or indirectly, such as quoted prices for similar assets or liabilities, quoted prices in markets that are not active, or other inputs that are observable or can be corroborated by observable market data for substantially the full term of the assets or liabilities.
		•		Level 3 — Unobservable inputs that are supported by little or no market activity and that are significant to the fair value of the assets or liabilities.
	The following tables present the Company’s fair value hierarchy for its cash equivalents and marketable securities, which are measured at fair value on a recurring basis as of March 31, 2014 and December 31, 2013:
			Fair Value Measurements at March 31, 2014 Using
			Level 1		Level 2		Level 3			Total
	Financial Assets:
	Money Market Instruments		$	20,445	$	—	$	—		$	20,445
	U.S. Treasury Notes			20,017		—		—			20,017
	Corporate and Agency Bonds			—		22,346		—			22,346
	Commercial Paper			—		1,397		—			1,397
	Total		$	40,462	$	23,743	$	—		$	64,205
			Fair Value Measurements at December 31, 2013 Using
			Level 1		Level 2		Level 3			Total
	Financial Assets:
Money Market Instruments		$	23,444	$	—	$	—		$	23,444
U.S. Treasury Notes			27,035		—		—			27,035
Corporate and Agency Bonds			—		12,688		—			12,688
Commercial Paper			—		1,000		—			1,000
Total		$	50,479	$	13,688	$	—		$	64,167
The Company has a contingent consideration liability associated with the acquisition of SinglePlatform in June 2012, which has been assessed at $0 as of December 31, 2013 and March 31, 2014. Contingent consideration is measured at fair value and is based on significant inputs not observable in the market, which represents a Level 3 measurement within the fair value hierarchy. The valuation of the contingent consideration liability uses assumptions and estimates to forecast a range of outcomes for the contingent consideration. The Company assesses these assumptions and estimates on a quarterly basis as additional data impacting the assumptions is obtained. Changes in the fair value of the contingent consideration liability related to updated assumptions and estimates are recognized within the consolidated statements of operations. The first three revenue targets were not met and the Company does not believe the final revenue target (measured as of June 30, 2014) will be met.
The significant unobservable inputs used in the fair value measurement of contingent consideration are the probabilities of successful achievement of the targeted revenues, the six month periods in which the revenues are expected to be achieved and the discount rate. Increases or decreases in any of the forecasted scenarios or probabilities of success would result in a higher or lower fair value measurement, respectively. Increases or decreases in the actual achievement of milestones in the relevant period as compared to the estimated achievement would result in a higher or lower fair value measurement, respectively.
Property and Equipment
Property and equipment are recorded at cost and depreciated using the straight-line method over the estimated useful life of the assets or, where applicable and if shorter, over the lease term. Upon retirement or sale, the cost of assets disposed of and the related accumulated depreciation are eliminated from the accounts and any resulting gain or loss is credited or charged to the statement of operations. Repairs and maintenance costs are expensed as incurred.
Estimated useful lives of assets are as follows:
Computer equipment		3 years
Software		3 years
Furniture and fixtures		5 years
Leasehold improvements		Shorter of life of lease or
		estimated useful life
Long-Lived Assets
The Company reviews the carrying values of its long-lived assets for possible impairment when events or changes in circumstance indicate that the related carrying amount may not be recoverable. Undiscounted cash flows are compared to the carrying value and when required, impairment losses on assets to be held and used are recognized based on the excess of the asset’s carrying amount over the fair value of the asset. Long-lived assets to be disposed of are reported at the lower of carrying amount or fair value less cost to sell.
Net Income (Loss) Per Share
Basic net income (loss) per share is computed by dividing net income (loss) by the weighted average number of unrestricted common shares outstanding for the period.
Diluted net income (loss) per share is computed by dividing net income (loss) by the sum of the weighted average number of unrestricted common shares outstanding during the period and the weighted average number of potential common shares from the assumed exercise of stock options and the vesting of shares of restricted common stock and restricted stock units using the “treasury stock” method when the effect is not anti-dilutive.
The following is a summary of the shares used in computing diluted net income (loss) per share:
(in thousands)
		Three months ended
		March 31,
		2014		2013
Weighted average shares used in calculating basic net income (loss) per share			31,289		30,630
Stock options			1,029		—
Warrants			1		—
Unvested restricted stock and restricted stock units			123		—
Shares used in computing diluted net income (loss) per share			32,442		30,630
The following common stock equivalents were excluded from the computation of diluted net income (loss) per share because they had an anti-dilutive impact either because the proceeds under the treasury stock method were in excess of the average fair market value for the period or because the Company had a net loss in the period:
(in thousands)
		Three months ended
		March 31,
		2014		2013
Options to purchase common stock			1,031		5,538
Unvested restricted stock and restricted stock units			268		588
Warrants to purchase common stock			—		1
Total options and warrants exercisable into common stock, restricted stock units issuable in common stock and restricted stock			1,299		6,127
Advertising Expense
The Company expenses advertising as incurred.
Accounting for Stock-Based Compensation
The Company values all stock-based compensation, including grants of stock options, restricted stock and restricted stock units, at fair value on the date of grant, and expenses the fair value over the applicable service period. The straight-line method is applied to all grants with service conditions, while the graded vesting method is applied to all grants with both service and performance conditions.
Income Taxes
Income taxes are provided for tax effects of transactions reported in the financial statements and consist of income taxes currently due plus deferred income taxes related to timing differences between the basis of certain assets and liabilities for financial statement and income tax reporting purposes. Deferred taxes are determined based on the difference between the financial statement and tax basis of assets and liabilities using enacted tax rates in effect in the years in which the differences are expected to reverse. A valuation allowance is provided if, based upon the weight of available evidence, it is more likely than not that some or all of the deferred tax assets will not be realized.
The Company accounts for uncertainty in income taxes recognized in the financial statements by applying a two-step process to determine the amount of tax benefit to be recognized. First, the tax position must be evaluated to determine the likelihood that it will be sustained upon external examination. If the tax position is deemed “more-likely-than-not” to be sustained, the tax position is then assessed to determine the amount of benefit to recognize in the financial statements. The amount of the benefit that may be recognized is the largest amount that has a greater than 50% likelihood of being realized upon ultimate settlement.
Segment Data
The Company manages its operations as a single segment for purposes of assessing performance and making operating decisions. Revenue is generated predominately in the U.S. and all significant assets are held in the U.S.

Goodwill_and_Acquired_Intangib

Goodwill and Acquired Intangible Assets	3 Months Ended
	Mar. 31, 2014
Goodwill And Intangible Assets Disclosure [Abstract]	'
Goodwill and Acquired Intangible Assets	'
	3. Goodwill and Acquired Intangible Assets
	The carrying amount of goodwill was $95,505 at March 31, 2014 and December 31, 2013. Goodwill is not amortized, but instead is reviewed for impairment at least annually in the fourth quarter or more frequently when events and circumstances occur indicating that the recorded goodwill may be impaired.
	Intangible assets consist of the following:
				March 31, 2014						December 31, 2013
		Estimated		Gross		Accumulated		Net Carrying		Gross		Accumulated		Net Carrying
		Useful Life		Carrying		Amortization		Amount		Carrying		Amortization		Amount
				Amount						Amount
	Developed technology		3 years	$	4,357	$	2,619	$	1,738	$	4,357	$	2,336	$	2,021
	Customer relationships		3.75 years		3,315		2,076		1,239		3,315		1,855		1,460
	Publisher relationships		5 years		710		260		450		710		225		485
	Trade name		5 years		570		209		361		570		181		389
				$	8,952	$	5,164	$	3,788	$	8,952	$	4,597	$	4,355
	The Company amortizes the intangible assets over the estimated useful lives noted above. Amortization of the developed technology and publisher relationships assets is on a straight-line basis as the pattern of consumption of the economic benefits of the intangible assets cannot be reliably determined. The Company also amortizes the trade name asset over its estimated useful life on a straight-line basis as the straight-line basis is not materially different than the pattern of consumption of economic benefit basis. Customer relationships are amortized over their useful life based on the pattern of consumption of economic benefit of the asset. Amortization commences once the asset has been placed in service. Amortization expense for intangible assets was $567 and $560 for the three months ended March 31, 2014 and 2013, respectively. Amortization relating to developed technology and publisher relationships is recorded within cost of revenue and amortization of customer relationships and trade name is recorded within sales and marketing expense. Future estimated amortization expense for intangible assets as of March 31, 2014 is as follows:
	Remainder of 2014	$	1,628
	2015		1,583
	2016		470
	2017		107
	Total	$	3,788

StockBased_Awards

Stock-Based Awards	3 Months Ended
	Mar. 31, 2014
Disclosure Of Compensation Related Costs Sharebased Payments [Abstract]	'
Stock-Based Awards	'
	4. Stock-Based Awards
	Stock Incentive Plan
	The Company’s 2011 Stock Incentive Plan (the “2011 Plan”) permits the Company to make grants of incentive stock options, non-statutory stock options, restricted stock, restricted stock units, stock appreciation rights and other stock-based awards with a maximum term of seven years. These awards may be granted to the Company’s employees, officers, directors, consultants, and advisors. The Company reserved 4,200,000 shares of its common stock for issuance under the 2011 Plan. Additionally, per the terms of the 2011 Plan, shares of common stock previously reserved for issuance under the 2007 Stock Incentive Plan as well as shares reserved for outstanding awards under the 1999 Stock Option/Stock Issuance Plan for which the awards are cancelled, forfeited, repurchased or otherwise result in common stock not being issued will be added to the number of shares available for issuance under the 2011 Plan. Awards that are granted with a per share or per unit purchase price less than 100% of fair market value as of the date of grant (e.g., restricted stock and restricted stock unit awards) shall count towards the total number of shares reserved for issuance under the 2011 Plan on a two-for-one basis. As of March 31, 2014, 1,067,381 shares of common stock are available for issuance under the 2011 Plan.
	Inducement Award Plan
	The Company’s 2012 Inducement Award Plan (the “2012 Inducement Plan”) provides for the grant of non-statutory stock options and restricted stock unit awards as an inducement to an individual’s entering into employment with the Company or in connection with an acquisition. The Company may issue up to an aggregate of 257,780 shares of common stock pursuant to the 2012 Inducement Plan, subject to adjustment in the event of stock splits and other similar events. Shares issued under the 2012 Inducement Plan may consist in whole or in part of authorized but unissued shares or may be issued shares that the Company has reacquired (provided that open market purchases of shares using the proceeds from the exercise of awards do not increase the number of shares available for future grants). Options granted under the 2012 Inducement Plan must be granted at an exercise price that is not less than 100% of the fair market value of the common stock on the date of grant and may not be granted for a term in excess of seven years.
	If an award granted under the 2012 Inducement Plan expires or is terminated, surrendered or canceled without having been fully exercised or is forfeited in whole or in part (including as the result of shares of common stock subject to such award being repurchased by the Company) or otherwise results in any common stock not being issued, the unused common stock covered by such award will become available for issuance pursuant to a new award under the 2012 Inducement Plan. As of March 31, 2014, there are 77,711 shares of common stock available for issuance under the 2012 Inducement Plan. On April 1, 2014, the Company’s board of directors voted to terminate the 2012 Inducement Plan. As a result, no additional awards will be granted under this plan.
	The Company applies the fair value recognition provisions for all stock-based awards granted or modified in accordance with authoritative guidance. Under this guidance the Company records compensation costs over the requisite service period of the award based on the grant-date fair value. The straight-line method is applied to all grants with service conditions, while the graded vesting method is applied to all grants with both service and performance conditions.
	Stock Options
	The Company grants stock options to certain employees and directors. The vesting of most of these awards is time-based and the restrictions typically lapse 25% after one year and quarterly thereafter for the next 36 months in the case of employees and 33% after one year and quarterly thereafter for the next 24 months in the case of directors.
	Restricted Stock Units
	Upon vesting, restricted stock units entitle the holder to one share of common stock for each restricted stock unit. All restricted stock units currently granted have been classified as equity instruments as their terms require settlement in shares. The Company has outstanding restricted stock units with service-based vesting conditions, service and performance-based vesting conditions and market-based vesting conditions.
	Restricted stock units with service-based vesting and service-based and performance-based vesting conditions are valued on the grant date using the grant date market price of the underlying shares. Service-based vesting restrictions lapse over periods generally ranging from two to four years. Restricted stock units with both service-based and performance-based vesting conditions consist of restricted stock units which vest upon the achievement of minimum number of years of service and a targeted revenue run rate (the “ 2012 Revenue RSUs”) or a compounded annual growth rate in revenue over a specified period of time (the “ 2013 Revenue RSUs”). The number of 2012 Revenue RSUs that will vest upon the achievement of the performance condition and the service condition will vary based on when the performance condition is satisfied, from a maximum of 100% of the number of target shares to a threshold of 25% of the number of target shares with no vesting, absent certain circumstances in a change of control of the Company, if the targeted threshold is not achieved. If the revenue targets are not achieved by March 31, 2017, the 2012 Revenue RSUs will expire unvested. The number of 2013 Revenue RSUs that will vest upon the achievement of the performance condition and the service condition will vary based on the actual compound annual growth rate in revenue, from a maximum of 125% of the number of target shares to a threshold of 50% of the number of target shares with no vesting, absent certain circumstances in a change of control of the Company, if the targeted threshold is not achieved. If the targets are not achieved by December 31, 2016, the 2013 Revenue RSUs will expire unvested. The Company also has outstanding a small number of restricted stock units with other performance-based vesting criteria.
	Restricted stock units with market-based vesting conditions consist of restricted stock units which vest upon achievement of Total Shareholder Return targets (the “TSR units”). The number of TSR units that will vest upon achievement of the Total Shareholder Return target will vary based on the level of achievement from a maximum of 125% of the target shares to a threshold of 50% of the target shares with no vesting, absent certain circumstances in a change of control of the Company, if the threshold requirements are not achieved or the employee is no longer with the Company at the end of the measurement period. The TSR units are valued using a Monte Carlo simulation model. The number of awards expected to be earned, based on achievement of the TSR market condition, is factored into the grant date Monte Carlo valuation for the TSR unit. Compensation cost is recognized regardless of the eventual number of awards that are earned based on the market condition and is recognized on a straight-line basis over the requisite service period.
	Stock Purchase Plan
	Under the Company’s 2007 Employee Stock Purchase Plan, as amended (the “Purchase Plan”), six-month offering periods begin on January 1 and July 1 of each year during which employees may elect to purchase shares of the Company’s common stock according to the terms of the offering. Prior to July 1, 2013, the per share purchase price for each offering was equal to 85% of the closing market price of the Company’s common stock on the last day of the offering period. Starting with the offering period that began on July 1, 2013, the per share purchase price for offerings is equal to the lesser of 85% of the closing market price of the Company’s common stock on the first day or last day of the offering period. As of March 31, 2014, 381,135 shares of common stock are available for issuance to participating employees under the Purchase Plan.
	Stock-Based Compensation Expense
	The Company recognized stock-based compensation expense on all awards in the following expense categories:
		Three months ended
		March 31,
		2014		2013
	Cost of revenue	$	442	$	399
	Research and development		1,020		831
	Sales and marketing		1,032		984
	General and administrative		1,420		1,327
		$	3,914	$	3,541
	The Company capitalized approximately $50 and $166 of stock-based compensation related to the development of internal use software for the three months ended March 31, 2014 and 2013, respectively.

Income_Taxes

Income Taxes	3 Months Ended
	Mar. 31, 2014
Income Tax Disclosure [Abstract]	'
Income Taxes	'
	5. Income Taxes
	For the three months ended March 31, 2014 and 2013, the Company recorded an income tax expense of $328 and an income tax benefit of $1,988, respectively. Income tax is related to federal, state, and to a lesser extent, foreign tax obligations. The Company’s effective tax rate may vary from period to period based on changes in estimated taxable income or loss, changes to federal, state or foreign tax laws, deductibility of certain costs and expenses, and as a result of acquisitions.
	The Company’s estimated effective tax rate for 2014, which has been applied to the Company’s income before income taxes for the three months ended March 31, 2014, varies from the statutory rate primarily due to non-deductible stock-based compensation expense, that increases the effective tax rate, partially offset by state research and development credits that decrease the effective tax rate. The U.S. federal research and development credit has not yet been enacted for 2014 and therefore, is not included in the Company’s estimated effective tax rate for 2014. The income tax expense for the first quarter of 2014 was further reduced by the impact of disqualifying dispositions of incentive stock options during the period. The Company’s estimated effective tax rate for 2013, which has been applied to the Company’s loss before income taxes for the three months ended March 31, 2013, varies from the statutory rate primarily due to 2013 federal and state research and development credits that decrease the effective tax rate, partially offset by non-deductible stock-based compensation expense, that increases the effective tax rate. Additionally, for the three months ended March 31, 2013, the income tax benefit was increased by the 2012 federal research and development credit, which was treated as a discrete item. The American Taxpayer Relief Act of 2012 (the “Act”) was enacted on January 2, 2013. The Act retroactively reinstated the federal research and development credit from January 1, 2012 through December 31, 2013. As a result of the change in the tax law, the Company recognized a benefit of $1,324 to income tax expense in the first quarter of 2013, the quarter in which the law was enacted for certain expenses incurred in 2012.
	The Company had net deferred tax assets of $10,377 at December 31, 2013, which did not change materially at March 31, 2014.
	The Company has not recorded any amounts for unrecognized tax benefits as of March 31, 2014 or December 31, 2013. As of March 31, 2014 and December 31, 2013, the Company had no accrued interest or tax penalties recorded.

Accrued_Expenses

Accrued Expenses	3 Months Ended
	Mar. 31, 2014
Payables And Accruals [Abstract]	'
Accrued Expenses	'
	6. Accrued Expenses
		March 31,		December 31,
		2014		2013
	Payroll and payroll related	$	5,103	$	4,106
	Licensed software and maintenance		1,197		1,197
	Marketing programs		710		575
	Other accrued expenses		4,957		5,025
		$	11,967	$	10,903

Commitments_and_Contingencies

Commitments and Contingencies	3 Months Ended
	Mar. 31, 2014
Commitments And Contingencies Disclosure [Abstract]	'
Commitments and Contingencies	'
	7. Commitments and Contingencies
	Office Leases
	The Company has a lease for its headquarters space in Waltham, Massachusetts (the “Lease”) that is effective through September 2022 with one ten-year extension option. The Lease includes space the Company is currently occupying as well as space that will be made available at various points in time during the term.
	The Company leases office space for a sales and support office in Colorado under a lease agreement effective through April 2019 with three three-year extension options. The Company also leases small amounts of general office space in Florida, New York, California and the United Kingdom under lease agreements that expire at various dates through 2018.
	Lease incentives, payment escalations and rent holidays specified in the lease agreements are accrued or deferred as appropriate such that rent expense per square foot is recognized on a straight-line basis over the terms of occupancy.
	At March 31, 2014 and December 31, 2013, the Company had both prepaid rent and accrued rent balances related to its office leases. The prepaid rent balance was $468 as of March 31, 2014, of which $198 was included in prepaid expenses and other current assets and $270 was included in other assets. The accrued rent balance was $2,159 as of March 31, 2014, of which $363 was included in accrued expenses and $1,796 was included in other long-term liabilities. The prepaid rent balance was $634 at December 31, 2013, of which $128 was included in prepaid expenses and other current assets and $506 was included in other assets. The accrued rent balance was $2,239 at December 31, 2013, of which $351 was included in accrued expenses and $1,888 was included in other long-term liabilities.
	Total rent expense under office leases was $2,320 and $1,970 for the three months ended March 31, 2014 and 2013, respectively.
	As of March 31, 2014, future minimum lease payments under noncancelable office leases are as follows:
	Remainder of 2014	$	6,408
	2015		9,238
	2016		10,194
	2017		10,153
	2018		9,747
	Thereafter		30,954
	Total	$	76,694
	Third-Party Hosting Agreements
	The Company has agreements with two affiliated vendors to provide specialized space and equipment and related services from which the Company hosts its software applications.
	Payment escalations and rent holidays specified in these agreements are accrued or deferred as appropriate such that rent expense per square foot is recognized on a straight-line basis over the terms of occupancy. As of March 31, 2014 and December 31, 2013, the Company had both prepaid rent and accrued rent balances related to these agreements. As of March 31, 2014, the Company had prepaid rent of $771, of which $342 was included in prepaid expenses and other current assets and $429 was included in other assets. Of the accrued rent balance of $176, $10 was included in accrued expenses and $166 was included in other long-term liabilities. As of December 31, 2013, the Company had prepaid rent of $861, of which $360 was included in prepaid expenses and other current assets and $501 was included in other assets. The accrued rent balance of $173 was included in other long-term liabilities.
	Total rent expense under hosting agreements was $1,063 and $1,007 for the three months ended March 31, 2014 and 2013, respectively.
	The agreements include payment commitments that expire at various dates through mid-2017. As of March 31, 2014, future minimum payments under the agreements are as follows:
	Remainder of 2014	$	2,875
	2015		3,938
	2016		4,049
	2017		775
	Total	$	11,637
	Vendor Commitments
	As of March 31, 2014, the Company had issued both cancellable and non-cancellable purchase orders to various vendors and entered into contractual commitments with various vendors totaling $19,994 related primarily to marketing programs and other non-marketing goods and services to be delivered over the next twelve months.
	Letters of Credit and Restricted Cash
	As of March 31, 2014 and December 31, 2013, the Company maintained a letter of credit totaling $1,300 for the benefit of the landlord of the Lease. The landlord can draw against the letter of credit in the event of default by the Company. The Company was required to maintain a cash balance of at least $1,300 as of March 31, 2014 and December 31, 2013, respectively, to secure the letter of credit. These amounts were classified as restricted cash in the balance sheet at March 31, 2014 and December 31, 2013.
	Contingent Consideration
	The former shareholders of SinglePlatform were eligible to receive consideration of up to $30,000, which was contingent on the achievement of certain revenue targets within the period from July 1, 2012 to June 30, 2014, measured in six month intervals. If such conditions were achieved, the consideration would have been payable in cash. As of March 31, 2014, the first three targets had not been met. Additionally, the Company does not believe the final target will be met. Accordingly, the Company’s accrual for this contingency as of March 31, 2014 and December 31, 2013 was $0.
	Indemnification Obligations
	The Company enters into standard indemnification agreements with the Company’s channel partners and certain other third parties in the ordinary course of business. Pursuant to these agreements, the Company indemnifies and agrees to reimburse the indemnified party for losses incurred by the indemnified party in connection with certain intellectual property infringement and other claims by any third party with respect to the Company’s business and technology. Based on historical information and information known as of March 31, 2014, the Company does not expect it will incur any significant liabilities under these indemnification agreements.
	Legal Matters
	On September 24, 2012, RPost Holdings, Inc., RPost Communications Limited and RMail Limited (collectively, “RPost”) filed a complaint in the U.S. District Court for the Eastern District of Texas that named the Company as a defendant in a lawsuit. The complaint, which was served on the Company on December 26, 2012, alleges that certain elements of the Company’s email marketing technology infringe five patents held by RPost. RPost seeks an award for damages in an unspecified amount and injunctive relief. On February 11, 2013, RPost amended its complaint to name five of the Company’s partners as defendants. Under the Company’s contractual agreements with these partners, the Company is obligated to indemnify them for claims related to patent infringement. The Company filed a motion to sever and stay the claims against its partners and multiple motions to dismiss the claims against the Company. In January 2014, the case was stayed pending the resolution of certain state court and bankruptcy court actions involving RPost, to which the Company is not a party. RPost has asked the court to reconsider the order to stay the case. This litigation is in its very early stages. As a result, neither the ultimate outcome of this litigation nor an estimate of a probable loss or any reasonably possible losses can be assessed at this time. Nevertheless, the Company believes that it has meritorious defenses to any claim of infringement and intends to defend itself vigorously.
	On November 14, 2012, the Company filed a complaint in the U.S. District Court for the District of Delaware against Umbanet, Inc. (“Umbanet”) seeking a declaratory judgment that two patents held by Umbanet (the “Umbanet Patents”) are not infringed by a customer’s use of the Company’s email marketing product and that such patents are invalid (the “Delaware Case”). The Company filed the Delaware Case in response to a complaint filed by Umbanet in the U.S. District Court for the District of New Jersey against one of the Company’s customers alleging that the customer’s use of the Company’s email marketing product infringed the Umbanet Patents (the “New Jersey Case”). Umbanet filed a motion in the Delaware Case seeking to dismiss the complaint or, in the alternative, stay the case pending resolution of the New Jersey Case. The Company filed a motion in the New Jersey Case seeking to stay the case pending resolution of the Delaware Case. In January 2014, the judge in the New Jersey Case ordered that the case should proceed notwithstanding the pending Delaware Case. Following this decision, the Company voluntarily withdrew the Delaware Case. In April 2014, the New Jersey Case was dismissed with prejudice as part of a larger settlement between the Company and Umbanet, which settlement had no material effect on the Company.
	On March 7, 2013, CreateAds LLC (“CreateAds”) filed a complaint in the U.S. District Court for the District of Delaware that named the Company as a defendant in a lawsuit. The complaint, which was served on the Company on March 8, 2013, alleges that certain elements of the Company’s email marketing technology infringe a patent held by CreateAds. CreateAds seeks an award for damages in an unspecified amount and injunctive relief. The Company filed a motion to dismiss the complaint. In February 2014, the case was stayed pending a decision by the United States Supreme Court in the appeal of a patent case with issues very similar to the ones pending in the Company’s motion to dismiss. CreateAds has asked the court to reconsider the order to stay the case. Following the Supreme Court’s decision, which is expected in June 2014, the district court will decide the Company’s motion to dismiss the CreateAds complaint. This litigation is in its very early stages. As a result, neither the ultimate outcome of this matter nor an estimate of a probable loss or any reasonably possible losses can be assessed at this time. Nevertheless, the Company believes that it has meritorious defenses to any claim of infringement and intends to defend the lawsuit vigorously.
	The Company is from time to time subject to various other legal proceedings and claims, either asserted or unasserted, which arise in the ordinary course of its business. While the outcome of these other claims cannot be predicted with certainty, management does not believe that the outcome of any of these other legal matters will have a material adverse effect on the Company’s results of operations or financial condition.

401k_Savings_Plan

401(k) Savings Plan	3 Months Ended
	Mar. 31, 2014
Compensation And Retirement Disclosure [Abstract]	'
401(k) Savings Plan	'
	8. 401(k) Savings Plan
	The Company has a defined contribution savings plan under Section 401(k) of the Internal Revenue Code. This plan covers substantially all employees who meet minimum age and service requirements and allows participants to defer a portion of their annual compensation on a pre-tax basis. Company contributions to the plan may be made at the discretion of the Board of Directors. The Company elected to make matching contributions for the plan years ending December 31, 2014 and 2013 at a rate of 100% of each employee’s contribution up to a maximum matching contribution of 3% of the employee’s compensation and at a rate of 50% of each employee’s contribution in excess of 3% up to a maximum of 5% of the employee’s compensation.
	Through March 31, 2014 and 2013, the Company made matching contributions of $863 and $664 for the plan years ended December 31, 2014 and 2013, respectively.

Summary_of_Significant_Account1

Summary of Significant Accounting Policies (Policies)	3 Months Ended
	Mar. 31, 2014
Accounting Policies [Abstract]	'
Basis of Presentation	'
	Basis of Presentation
	The accompanying consolidated financial statements include those of the Company and its subsidiaries, after elimination of all intercompany accounts and transactions. The accompanying consolidated financial statements have been prepared in conformity with accounting principles generally accepted in the United States of America (“GAAP”).
	The condensed consolidated balance sheet at December 31, 2013 was derived from audited financial statements, but does not include all disclosures required by GAAP. The accompanying unaudited condensed consolidated financial statements as of March 31, 2014 and for the three months ended March 31, 2014 and 2013 have been prepared by the Company, pursuant to the rules and regulations of the Securities and Exchange Commission (“SEC”) for interim financial statements. Certain information and footnote disclosures normally included in financial statements prepared in accordance with GAAP have been condensed or omitted pursuant to such rules and regulations. However, the Company believes that the disclosures are adequate to make the information presented not misleading. These condensed consolidated financial statements should be read in conjunction with the Company’s audited consolidated financial statements and the notes thereto for the year ended December 31, 2013 included in the Company’s Annual Report on Form 10-K, File Number 001-33707, on file with the SEC.
	In the opinion of management, all adjustments, consisting only of normal recurring adjustments necessary for a fair statement of the Company’s consolidated financial position as of March 31, 2014 and consolidated results of operations for the three months ended March 31, 2014 and 2013 and consolidated cash flows for the three months ended March 31, 2014 and 2013 have been made. The results of operations for the three months ended March 31, 2014 are not necessarily indicative of the results of operations that may be expected for the year ending December 31, 2014.
Use of Estimates	'
	Use of Estimates
	The preparation of financial statements in conformity with GAAP requires management to make estimates and assumptions that affect the reported amounts of assets and liabilities and the disclosure of contingent assets and liabilities at the date of the financial statements and the reported amounts of revenue and expenses during the reporting period. On an ongoing basis, management evaluates these estimates, judgments and assumptions, including those related to revenue recognition, stock-based compensation, goodwill and acquired intangible assets, capitalization of software and website development costs, liability for contingent consideration, litigation accruals and income taxes. The Company bases these estimates on historical and anticipated results and trends and on various other assumptions that the Company believes are reasonable under the circumstances, including assumptions as to future events. These estimates form the basis for making judgments about the carrying values of assets and liabilities and recorded revenue and expenses that are not readily apparent from other sources. Actual results could differ from these estimates.
Revenue Recognition	'
	Revenue Recognition
	The Company provides access to its products primarily through subscription arrangements whereby the customer is charged a fee for access for a defined term. Subscription arrangements include access to use the Company’s software via the Internet and support services, such as telephone, email and chat support. When there is evidence of an arrangement, the fee is fixed or determinable and collectability is deemed reasonably assured, the Company recognizes revenue on a daily basis over the subscription period as the services are delivered. Delivery is considered to have commenced at the time the customer has paid for the products and has access to the account via a log-in and password. The Company generates revenue from its SaveLocal product by charging a fee to its customers based on the number of deals sold by its customers and the value of the successful deal. The Company recognizes revenue from the fee charged when there is evidence of an arrangement, the fee is fixed or determinable and collectability is deemed reasonably assured. The Company also offers ancillary services to its customers related to its subscription-based products such as custom services and training. When sold together, revenue from custom services, training and subscription products are accounted for separately based on vendor-specific objective evidence of fair value of each of the services as those services have value on a standalone basis and do not involve a significant degree of risk or unique acceptance criteria. Revenue from custom services and training is recognized as the services are performed.
Deferred Revenue	'
	Deferred Revenue
	Deferred revenue consists of payments received in advance of delivery of the Company’s products described above and is recognized as the revenue recognition criteria are met. The Company’s customers generally pay for services in advance on a monthly, semiannual or annual basis.
Accounts Receivable	'
	Accounts Receivable
	Management reviews accounts receivable on a periodic basis to determine if any receivables will potentially be uncollectible. The Company reserves for receivables that are determined to be uncollectible, if any, in its allowance for doubtful accounts. After the Company has exhausted all collection efforts, the outstanding receivable is written off against the allowance.
Concentration of Credit Risk and Significant Products and Customers	'
	Concentration of Credit Risk and Significant Products and Customers
	Financial instruments that potentially expose the Company to concentrations of credit risk consist primarily of cash, cash equivalents and marketable securities. As of March 31, 2014 and December 31, 2013, the Company had substantially all cash and investment balances at certain financial institutions without or in excess of federally insured limits, however, the Company maintains its cash balances and custody of its marketable securities with accredited financial institutions. The Company does not believe that it is subject to unusual credit risk beyond the normal credit risk associated with commercial banking relationships.
	For the three months ended March 31, 2014 and 2013, revenue from the Company’s email marketing product alone as a percentage of total revenue was approximately 84% and 85%, respectively. No customer accounted for more than 10% of total revenue during these periods.
Goodwill and Acquired Intangible Assets	'
	Goodwill and Acquired Intangible Assets
	The Company records goodwill when consideration paid in a business acquisition exceeds the fair value of the net tangible assets and the identified intangible assets acquired. Goodwill is not amortized, but rather is tested for impairment annually or more frequently if facts and circumstances warrant a review. The Company performs its annual assessment for impairment of goodwill on November 30th and has determined that there is a single reporting unit for the purpose of conducting this annual goodwill impairment assessment.
	Intangible assets are recorded at their estimated fair values at the date of acquisition. The Company amortizes acquired intangible assets over their estimated useful lives based on the pattern of consumption of the economic benefits or, if that pattern cannot be readily determined, on a straight-line basis.
Software and Web Site Development Costs	'
	Software and Web Site Development Costs
	Research and development costs are expensed as incurred and primarily include salaries, fees to consultants and other related costs. Relative to development costs of its on-demand products and website, the Company capitalizes certain direct costs to develop functionality as well as certain upgrades and enhancements that are probable to result in additional functionality. The costs incurred in the preliminary stages of development are expensed as incurred. Once an application has reached the development stage, internal and external costs, if direct and incremental, are capitalized as part of property and equipment until the software is substantially complete and ready for its intended use. Capitalized software is amortized over a three-year period in the expense category to which the software relates.
Foreign Currency Translation	'
	Foreign Currency Translation
	The functional currency of the Company’s UK operations is deemed to be the British pound. Accordingly, the assets and liabilities of the Company’s UK subsidiary are translated into United States dollars using the period-end exchange rate, and income and expense items are translated using the average exchange rate during the period. Cumulative translation adjustments are reflected as a separate component of stockholders’ equity. Foreign currency transaction gains and losses are charged to other income (expense) and were not material to the Company’s operations.
Comprehensive Income (Loss)	'
	Comprehensive Income (Loss)
	Comprehensive income (loss) includes net income (loss), as well as other changes in stockholders’ equity that result from transactions and economic events other than those with stockholders. The Company’s only elements of other comprehensive income (loss) are unrealized gains and losses on available-for-sale securities and translation adjustments.
Cash and Cash Equivalents	'
	Cash and Cash Equivalents
	The Company considers all highly liquid investments with original maturities of three months or less at the time of acquisition to be cash equivalents. The Company also considers receivables related to customer credit card purchases of $3,034 and $2,901 as of March 31, 2014 and December 31, 2013, respectively, to be equivalent to cash. Cash equivalents are stated at fair value.
Marketable Securities	'
	Marketable Securities
	The Company’s marketable securities are classified as available-for-sale and are carried at fair value with the unrealized gains and losses reported as a component of accumulated other comprehensive income (loss) in stockholders’ equity. Realized gains and losses and declines in value judged to be other than temporary are included as a component of interest and other income (expense) based on the specific identification method.
	At March 31, 2014, marketable securities by security type consisted of:
			Amortized		Gross		Gross			Estimated
			Cost		Unrealized		Unrealized			Fair
					Gains		Losses			Value
	U.S. Treasury Notes		$	20,001	$	16	$	—		$	20,017
	Corporate and Agency Bonds			22,351		7		(12	)		22,346
	Commercial Paper			1,397		—		—			1,397
	Total		$	43,749	$	23	$	(12	)	$	43,760
	At March 31, 2014, marketable securities consisted of investments that mature within one year with the exception of government treasuries and corporate and agency bonds with a fair value of $21,964, which have maturities within two years.
	At December 31, 2013, marketable securities by security type consisted of:
			Amortized		Gross		Gross			Estimated
			Cost		Unrealized		Unrealized			Fair
					Gains		Losses			Value
	U.S. Treasury Notes		$	27,022	$	13	$	—		$	27,035
	Corporate and Agency Bonds			12,684		4		—			12,688
	Commercial Paper			1,000		—		—			1,000
	Total		$	40,706	$	17	$	—		$	40,723
Fair Value of Financial Instruments	'
	Fair Value of Financial Instruments
	Certain assets and liabilities are carried at fair value under GAAP. Fair value is defined as the exchange price that would be received for an asset or paid to transfer a liability (an exit price) in the principal or most advantageous market for the asset or liability in an orderly transaction between market participants on the measurement date. Valuation techniques used to measure fair value must maximize the use of observable inputs and minimize the use of unobservable inputs. A fair value hierarchy based on three levels of inputs, of which the first two are considered observable and the last is considered unobservable, is used to measure fair value:
		•		Level 1 — Quoted prices in active markets for identical assets or liabilities.
		•		Level 2 — Inputs other than Level 1 that are observable, either directly or indirectly, such as quoted prices for similar assets or liabilities, quoted prices in markets that are not active, or other inputs that are observable or can be corroborated by observable market data for substantially the full term of the assets or liabilities.
		•		Level 3 — Unobservable inputs that are supported by little or no market activity and that are significant to the fair value of the assets or liabilities.
	The following tables present the Company’s fair value hierarchy for its cash equivalents and marketable securities, which are measured at fair value on a recurring basis as of March 31, 2014 and December 31, 2013:
			Fair Value Measurements at March 31, 2014 Using
			Level 1		Level 2		Level 3			Total
	Financial Assets:
	Money Market Instruments		$	20,445	$	—	$	—		$	20,445
	U.S. Treasury Notes			20,017		—		—			20,017
	Corporate and Agency Bonds			—		22,346		—			22,346
	Commercial Paper			—		1,397		—			1,397
	Total		$	40,462	$	23,743	$	—		$	64,205
			Fair Value Measurements at December 31, 2013 Using
			Level 1		Level 2		Level 3			Total
	Financial Assets:
	Money Market Instruments		$	23,444	$	—	$	—		$	23,444
	U.S. Treasury Notes			27,035		—		—			27,035
	Corporate and Agency Bonds			—		12,688		—			12,688
	Commercial Paper			—		1,000		—			1,000
	Total		$	50,479	$	13,688	$	—		$	64,167
	The Company has a contingent consideration liability associated with the acquisition of SinglePlatform in June 2012, which has been assessed at $0 as of December 31, 2013 and March 31, 2014. Contingent consideration is measured at fair value and is based on significant inputs not observable in the market, which represents a Level 3 measurement within the fair value hierarchy. The valuation of the contingent consideration liability uses assumptions and estimates to forecast a range of outcomes for the contingent consideration. The Company assesses these assumptions and estimates on a quarterly basis as additional data impacting the assumptions is obtained. Changes in the fair value of the contingent consideration liability related to updated assumptions and estimates are recognized within the consolidated statements of operations. The first three revenue targets were not met and the Company does not believe the final revenue target (measured as of June 30, 2014) will be met.
	The significant unobservable inputs used in the fair value measurement of contingent consideration are the probabilities of successful achievement of the targeted revenues, the six month periods in which the revenues are expected to be achieved and the discount rate. Increases or decreases in any of the forecasted scenarios or probabilities of success would result in a higher or lower fair value measurement, respectively. Increases or decreases in the actual achievement of milestones in the relevant period as compared to the estimated achievement would result in a higher or lower fair value measurement, respectively.
Property and Equipment	'
	Property and Equipment
	Property and equipment are recorded at cost and depreciated using the straight-line method over the estimated useful life of the assets or, where applicable and if shorter, over the lease term. Upon retirement or sale, the cost of assets disposed of and the related accumulated depreciation are eliminated from the accounts and any resulting gain or loss is credited or charged to the statement of operations. Repairs and maintenance costs are expensed as incurred.
	Estimated useful lives of assets are as follows:
	Computer equipment		3 years
	Software		3 years
	Furniture and fixtures		5 years
	Leasehold improvements		Shorter of life of lease or
			estimated useful life
Long-Lived Assets	'
	Long-Lived Assets
	The Company reviews the carrying values of its long-lived assets for possible impairment when events or changes in circumstance indicate that the related carrying amount may not be recoverable. Undiscounted cash flows are compared to the carrying value and when required, impairment losses on assets to be held and used are recognized based on the excess of the asset’s carrying amount over the fair value of the asset. Long-lived assets to be disposed of are reported at the lower of carrying amount or fair value less cost to sell.
Net Income (Loss) Per Share	'
	Net Income (Loss) Per Share
	Basic net income (loss) per share is computed by dividing net income (loss) by the weighted average number of unrestricted common shares outstanding for the period.
	Diluted net income (loss) per share is computed by dividing net income (loss) by the sum of the weighted average number of unrestricted common shares outstanding during the period and the weighted average number of potential common shares from the assumed exercise of stock options and the vesting of shares of restricted common stock and restricted stock units using the “treasury stock” method when the effect is not anti-dilutive.
	The following is a summary of the shares used in computing diluted net income (loss) per share:
	(in thousands)
			Three months ended
			March 31,
			2014		2013
	Weighted average shares used in calculating basic net income (loss) per share			31,289		30,630
	Stock options			1,029		—
	Warrants			1		—
	Unvested restricted stock and restricted stock units			123		—
	Shares used in computing diluted net income (loss) per share			32,442		30,630
	The following common stock equivalents were excluded from the computation of diluted net income (loss) per share because they had an anti-dilutive impact either because the proceeds under the treasury stock method were in excess of the average fair market value for the period or because the Company had a net loss in the period:
	(in thousands)
			Three months ended
			March 31,
			2014		2013
	Options to purchase common stock			1,031		5,538
	Unvested restricted stock and restricted stock units			268		588
	Warrants to purchase common stock			—		1
	Total options and warrants exercisable into common stock, restricted stock units issuable in common stock and restricted stock			1,299		6,127
Advertising Expense	'
	Advertising Expense
	The Company expenses advertising as incurred.
Accounting for Stock-Based Compensation	'
	Accounting for Stock-Based Compensation
	The Company values all stock-based compensation, including grants of stock options, restricted stock and restricted stock units, at fair value on the date of grant, and expenses the fair value over the applicable service period. The straight-line method is applied to all grants with service conditions, while the graded vesting method is applied to all grants with both service and performance conditions.
Income Taxes	'
	Income Taxes
	Income taxes are provided for tax effects of transactions reported in the financial statements and consist of income taxes currently due plus deferred income taxes related to timing differences between the basis of certain assets and liabilities for financial statement and income tax reporting purposes. Deferred taxes are determined based on the difference between the financial statement and tax basis of assets and liabilities using enacted tax rates in effect in the years in which the differences are expected to reverse. A valuation allowance is provided if, based upon the weight of available evidence, it is more likely than not that some or all of the deferred tax assets will not be realized.
	The Company accounts for uncertainty in income taxes recognized in the financial statements by applying a two-step process to determine the amount of tax benefit to be recognized. First, the tax position must be evaluated to determine the likelihood that it will be sustained upon external examination. If the tax position is deemed “more-likely-than-not” to be sustained, the tax position is then assessed to determine the amount of benefit to recognize in the financial statements. The amount of the benefit that may be recognized is the largest amount that has a greater than 50% likelihood of being realized upon ultimate settlement.
Segment Data	'
	Segment Data
	The Company manages its operations as a single segment for purposes of assessing performance and making operating decisions. Revenue is generated predominately in the U.S. and all significant assets are held in the U.S.

Summary_of_Significant_Account2

Summary of Significant Accounting Policies (Tables)	3 Months Ended
	Mar. 31, 2014
Accounting Policies [Abstract]	'
Summary of Marketable Securities by Security Type	'
	At March 31, 2014, marketable securities by security type consisted of:
		Amortized		Gross		Gross			Estimated
		Cost		Unrealized		Unrealized			Fair
				Gains		Losses			Value
	U.S. Treasury Notes	$	20,001	$	16	$	—		$	20,017
	Corporate and Agency Bonds		22,351		7		(12	)		22,346
	Commercial Paper		1,397		—		—			1,397
	Total	$	43,749	$	23	$	(12	)	$	43,760
	At March 31, 2014, marketable securities consisted of investments that mature within one year with the exception of government treasuries and corporate and agency bonds with a fair value of $21,964, which have maturities within two years.
	At December 31, 2013, marketable securities by security type consisted of:
		Amortized		Gross		Gross			Estimated
		Cost		Unrealized		Unrealized			Fair
				Gains		Losses			Value
	U.S. Treasury Notes	$	27,022	$	13	$	—		$	27,035
	Corporate and Agency Bonds		12,684		4		—			12,688
	Commercial Paper		1,000		—		—			1,000
	Total	$	40,706	$	17	$	—		$	40,723
Fair Value Hierarchy for Cash Equivalents and Marketable Securities Measured at Fair Value on Recurring Basis	'
	The following tables present the Company’s fair value hierarchy for its cash equivalents and marketable securities, which are measured at fair value on a recurring basis as of March 31, 2014 and December 31, 2013:
		Fair Value Measurements at March 31, 2014 Using
		Level 1		Level 2		Level 3			Total
	Financial Assets:
	Money Market Instruments	$	20,445	$	—	$	—		$	20,445
	U.S. Treasury Notes		20,017		—		—			20,017
	Corporate and Agency Bonds		—		22,346		—			22,346
	Commercial Paper		—		1,397		—			1,397
	Total	$	40,462	$	23,743	$	—		$	64,205
		Fair Value Measurements at December 31, 2013 Using
		Level 1		Level 2		Level 3			Total
	Financial Assets:
	Money Market Instruments	$	23,444	$	—	$	—		$	23,444
	U.S. Treasury Notes		27,035		—		—			27,035
	Corporate and Agency Bonds		—		12,688		—			12,688
	Commercial Paper		—		1,000		—			1,000
	Total	$	50,479	$	13,688	$	—		$	64,167
Estimated Useful Lives of Assets	'
	Estimated useful lives of assets are as follows:
	Computer equipment	3 years
	Software	3 years
	Furniture and fixtures	5 years
	Leasehold improvements	Shorter of life of lease or
		estimated useful life
Summary of Shares used in Computing Diluted Net Income (Loss) Per Share	'
	The following is a summary of the shares used in computing diluted net income (loss) per share:
	(in thousands)
		Three months ended
		March 31,
		2014		2013
	Weighted average shares used in calculating basic net income (loss) per share		31,289		30,630
	Stock options		1,029		—
	Warrants		1		—
	Unvested restricted stock and restricted stock units		123		—
	Shares used in computing diluted net income (loss) per share		32,442		30,630
Common Stock Equivalents Excluded from Computation of Diluted Net Income (Loss) Per Share	'
	The following common stock equivalents were excluded from the computation of diluted net income (loss) per share because they had an anti-dilutive impact either because the proceeds under the treasury stock method were in excess of the average fair market value for the period or because the Company had a net loss in the period:
	(in thousands)
		Three months ended
		March 31,
		2014		2013
	Options to purchase common stock		1,031		5,538
	Unvested restricted stock and restricted stock units		268		588
	Warrants to purchase common stock		—		1
	Total options and warrants exercisable into common stock, restricted stock units issuable in common stock and restricted stock		1,299		6,127

Goodwill_and_Acquired_Intangib1

Goodwill and Acquired Intangible Assets (Tables)	3 Months Ended
	Mar. 31, 2014
Goodwill And Intangible Assets Disclosure [Abstract]	'
Intangible Assets	'
	Intangible assets consist of the following:
				March 31, 2014						December 31, 2013
		Estimated		Gross		Accumulated		Net Carrying		Gross		Accumulated		Net Carrying
		Useful Life		Carrying		Amortization		Amount		Carrying		Amortization		Amount
				Amount						Amount
	Developed technology		3 years	$	4,357	$	2,619	$	1,738	$	4,357	$	2,336	$	2,021
	Customer relationships		3.75 years		3,315		2,076		1,239		3,315		1,855		1,460
	Publisher relationships		5 years		710		260		450		710		225		485
	Trade name		5 years		570		209		361		570		181		389
				$	8,952	$	5,164	$	3,788	$	8,952	$	4,597	$	4,355
Future Estimated Amortization Expense for Intangible Assets	'
	Future estimated amortization expense for intangible assets as of March 31, 2014 is as follows:
	Remainder of 2014	$	1,628
	2015		1,583
	2016		470
	2017		107
	Total	$	3,788

StockBased_Awards_Tables

Stock-Based Awards (Tables)	3 Months Ended
	Mar. 31, 2014
Disclosure Of Compensation Related Costs Sharebased Payments [Abstract]	'
Recognized Stock-Based Compensation Expense	'
	The Company recognized stock-based compensation expense on all awards in the following expense categories:
		Three months ended
		March 31,
		2014		2013
	Cost of revenue	$	442	$	399
	Research and development		1,020		831
	Sales and marketing		1,032		984
	General and administrative		1,420		1,327
		$	3,914	$	3,541

Accrued_Expenses_Tables

Accrued Expenses (Tables)	3 Months Ended
	Mar. 31, 2014
Payables And Accruals [Abstract]	'
Components of Accrued Expenses	'
		March 31,		December 31,
		2014		2013
	Payroll and payroll related	$	5,103	$	4,106
	Licensed software and maintenance		1,197		1,197
	Marketing programs		710		575
	Other accrued expenses		4,957		5,025
		$	11,967	$	10,903

Commitments_and_Contingencies_

Commitments and Contingencies (Tables)	3 Months Ended
	Mar. 31, 2014
Office Leases [Member]	'
Future Minimum Lease Payments under Leases and Agreements	'
	As of March 31, 2014, future minimum lease payments under noncancelable office leases are as follows:
	Remainder of 2014	$	6,408
	2015		9,238
	2016		10,194
	2017		10,153
	2018		9,747
	Thereafter		30,954
	Total	$	76,694
Third-Party Hosting Agreements [Member]	'
Future Minimum Lease Payments under Leases and Agreements	'
	As of March 31, 2014, future minimum payments under the agreements are as follows:
	Remainder of 2014	$	2,875
	2015		3,938
	2016		4,049
	2017		775
	Total	$	11,637

Summary_of_Significant_Account3

Summary of Significant Accounting Policies - Additional Information (Detail) (USD $)

3 Months Ended

3 Months Ended

3 Months Ended

In Thousands, unless otherwise specified

Mar. 31, 2014

Dec. 31, 2013

Mar. 31, 2014

Dec. 31, 2013

Mar. 31, 2014

Mar. 31, 2013

Mar. 31, 2014

Mar. 31, 2014

Mar. 31, 2013

Mar. 31, 2014

Mar. 31, 2014

Mar. 31, 2014

SinglePlatform [Member]

SinglePlatform [Member]

Sales [Member]

Sales [Member]

Maximum [Member]

Minimum [Member]

Minimum [Member]

Government Treasuries, Corporate and Agency Bonds [Member]

Corporate and Agency Bonds [Member]

Software and Website Development Costs [Member]

Customer

Customer

Sales [Member]

Sales [Member]

Maximum [Member]

Summary Of Significant Accounting Policies [Line Items]

'

'

'

'

'

'

'

'

'

'

'

'

Percentage of total revenue received

'

'

'

'

84.00%

85.00%

'

10.00%

10.00%

'

'

'

Number of customers accounted for more than specified percentage of revenue

'

'

'

'

0

0

'

'

'

'

'

'

Estimated economic life of the developed technology related to acquisition of SinglePlatform

'

'

'

'

'

'

'

'

'

'

'

'3 years

Cash and cash equivalents and short term investments maturity period

'3 months

'

'

'

'

'

'

'

'

'

'

'

Credit card receivables

$3,034

$2,901

'

'

'

'

'

'

'

'

'

'

Maturity period for marketable securities classified as available-for-sale

'

'

'

'

'

'

'1 year

'

'

'2 years

'

'

Fair value of agency bonds and treasury notes classified as available-for-sale securities

'

'

'

'

'

'

'

'

'

'

21,964

'

Fair value of the contingent consideration liability

$0

$0

$0

$0

'

'

'

'

'

'

'

'

Interval period to measure revenue targets

'6 months

'

'

'

'

'

'

'

'

'

'

'

Minimum percentage of probability of realizing the benefit upon ultimate settlement

50.00%

'

'

'

'

'

'

'

'

'

'

'

Summary_of_Significant_Account4

Summary of Significant Accounting Policies - Summary of Marketable Securities by Security Type (Detail) (USD $)	Mar. 31, 2014	Dec. 31, 2013
In Thousands, unless otherwise specified
Schedule of Available-for-sale Securities [Line Items]	'	'
Amortized Cost	$43,749	$40,706
Gross Unrealized Gains	23	17
Gross Unrealized Losses	-12	'
Estimated Fair Value	43,760	40,723
U.S. Treasury Notes [Member]	'	'
Schedule of Available-for-sale Securities [Line Items]	'	'
Amortized Cost	20,001	27,022
Gross Unrealized Gains	16	13
Gross Unrealized Losses	'	'
Estimated Fair Value	20,017	27,035
Corporate and Agency Bonds [Member]	'	'
Schedule of Available-for-sale Securities [Line Items]	'	'
Amortized Cost	22,351	12,684
Gross Unrealized Gains	7	4
Gross Unrealized Losses	-12	'
Estimated Fair Value	22,346	12,688
Commercial Paper [Member]	'	'
Schedule of Available-for-sale Securities [Line Items]	'	'
Amortized Cost	1,397	1,000
Gross Unrealized Gains	'	'
Gross Unrealized Losses	'	'
Estimated Fair Value	$1,397	$1,000

Summary_of_Significant_Account5

Summary of Significant Accounting Policies - Fair Value Hierarchy for Cash Equivalents and Marketable Securities Measured at Fair Value on Recurring Basis (Detail) (Recurring [Member], USD $)	Mar. 31, 2014	Dec. 31, 2013
In Thousands, unless otherwise specified
Financial Assets:	'	'
Total	$64,205	$64,167
Money Market Instruments [Member]	'	'
Financial Assets:	'	'
Cash and cash equivalents fair value disclosure	20,445	23,444
U.S. Treasury Notes [Member]	'	'
Financial Assets:	'	'
Available for sale securities fair value disclosure	20,017	27,035
Corporate and Agency Bonds [Member]	'	'
Financial Assets:	'	'
Available for sale securities fair value disclosure	22,346	12,688
Commercial Paper [Member]	'	'
Financial Assets:	'	'
Available for sale securities fair value disclosure	1,397	1,000
Level 1 [Member]	'	'
Financial Assets:	'	'
Total	40,462	50,479
Level 1 [Member] | Money Market Instruments [Member]	'	'
Financial Assets:	'	'
Cash and cash equivalents fair value disclosure	20,445	23,444
Level 1 [Member] | U.S. Treasury Notes [Member]	'	'
Financial Assets:	'	'
Available for sale securities fair value disclosure	20,017	27,035
Level 1 [Member] | Corporate and Agency Bonds [Member]	'	'
Financial Assets:	'	'
Available for sale securities fair value disclosure	'	'
Level 1 [Member] | Commercial Paper [Member]	'	'
Financial Assets:	'	'
Available for sale securities fair value disclosure	'	'
Level 2 [Member]	'	'
Financial Assets:	'	'
Total	23,743	13,688
Level 2 [Member] | Money Market Instruments [Member]	'	'
Financial Assets:	'	'
Cash and cash equivalents fair value disclosure	'	'
Level 2 [Member] | U.S. Treasury Notes [Member]	'	'
Financial Assets:	'	'
Available for sale securities fair value disclosure	'	'
Level 2 [Member] | Corporate and Agency Bonds [Member]	'	'
Financial Assets:	'	'
Available for sale securities fair value disclosure	22,346	12,688
Level 2 [Member] | Commercial Paper [Member]	'	'
Financial Assets:	'	'
Available for sale securities fair value disclosure	1,397	1,000
Level 3 [Member]	'	'
Financial Assets:	'	'
Total	'	'
Level 3 [Member] | Money Market Instruments [Member]	'	'
Financial Assets:	'	'
Cash and cash equivalents fair value disclosure	'	'
Level 3 [Member] | U.S. Treasury Notes [Member]	'	'
Financial Assets:	'	'
Available for sale securities fair value disclosure	'	'
Level 3 [Member] | Corporate and Agency Bonds [Member]	'	'
Financial Assets:	'	'
Available for sale securities fair value disclosure	'	'
Level 3 [Member] | Commercial Paper [Member]	'	'
Financial Assets:	'	'
Available for sale securities fair value disclosure	'	'

Summary_of_Significant_Account6

Summary of Significant Accounting Policies - Estimated Useful Lives of Assets (Detail)	3 Months Ended
	Mar. 31, 2014
Computer Equipment [Member]	'
Property, Plant and Equipment [Line Items]	'
Estimated useful lives of assets	'3 years
Software [Member]	'
Property, Plant and Equipment [Line Items]	'
Estimated useful lives of assets	'3 years
Furniture and Fixtures [Member]	'
Property, Plant and Equipment [Line Items]	'
Estimated useful lives of assets	'5 years
Leasehold Improvements [Member]	'
Property, Plant and Equipment [Line Items]	'
Estimated useful lives of Leasehold improvements	'Shorter of life of lease or estimated useful life

Summary_of_Significant_Account7

Summary of Significant Accounting Policies - Summary of Shares used in Computing Diluted Net Income (Loss) Per Share (Detail)	3 Months Ended
In Thousands, unless otherwise specified	Mar. 31, 2014	Mar. 31, 2013
Earnings Per Share, Diluted, by Common Class, Including Two Class Method [Line Items]	'	'
Weighted average shares used in calculating basic net income (loss) per share	31,289	30,630
Warrants	1	'
Shares used in computing diluted net income (loss) per share	32,442	30,630
Stock Options [Member]	'	'
Earnings Per Share, Diluted, by Common Class, Including Two Class Method [Line Items]	'	'
Stock options and unvested restricted stock	1,029	'
Unvested Restricted Stock and Restricted Stock Units [Member]	'	'
Earnings Per Share, Diluted, by Common Class, Including Two Class Method [Line Items]	'	'
Stock options and unvested restricted stock	123	'

Summary_of_Significant_Account8

Summary of Significant Accounting Policies - Common Stock Equivalents Excluded from Computation of Diluted Net Income (Loss) Per Share (Detail)	3 Months Ended
In Thousands, unless otherwise specified	Mar. 31, 2014	Mar. 31, 2013
Antidilutive Securities Excluded from Computation of Earnings Per Share [Line Items]	'	'
Total options and warrants exercisable into common stock, restricted stock units issuable in common stock and restricted stock	1,299	6,127
Stock Options [Member]	'	'
Antidilutive Securities Excluded from Computation of Earnings Per Share [Line Items]	'	'
Total options and warrants exercisable into common stock, restricted stock units issuable in common stock and restricted stock	1,031	5,538
Unvested Restricted Stock and Restricted Stock Units [Member]	'	'
Antidilutive Securities Excluded from Computation of Earnings Per Share [Line Items]	'	'
Total options and warrants exercisable into common stock, restricted stock units issuable in common stock and restricted stock	268	588
Warrants [Member]	'	'
Antidilutive Securities Excluded from Computation of Earnings Per Share [Line Items]	'	'
Total options and warrants exercisable into common stock, restricted stock units issuable in common stock and restricted stock	'	1

Goodwill_and_Acquired_Intangib2

Goodwill and Acquired Intangible Assets - Additional Information (Detail) (USD $)	3 Months Ended
In Thousands, unless otherwise specified	Mar. 31, 2014	Mar. 31, 2013	Dec. 31, 2013
Goodwill And Intangible Assets Disclosure [Abstract]	'	'	'
Carrying amount of goodwill	$95,505	'	$95,505
Amortization expense for intangible assets	$567	$560	'

Goodwill_and_Acquired_Intangib3

Goodwill and Acquired Intangible Assets - Intangible Assets (Detail) (USD $)	3 Months Ended
In Thousands, unless otherwise specified	Mar. 31, 2014	Dec. 31, 2013
Finite-Lived Intangible Assets [Line Items]	'	'
Gross Carrying Amount	$8,952	$8,952
Accumulated Amortization	5,164	4,597
Net Carrying Amount	3,788	4,355
Developed Technology [Member]	'	'
Finite-Lived Intangible Assets [Line Items]	'	'
Estimated Useful Life	'3 years	'
Gross Carrying Amount	4,357	4,357
Accumulated Amortization	2,619	2,336
Net Carrying Amount	1,738	2,021
Customer Relationships [Member]	'	'
Finite-Lived Intangible Assets [Line Items]	'	'
Estimated Useful Life	'3 years 9 months	'
Gross Carrying Amount	3,315	3,315
Accumulated Amortization	2,076	1,855
Net Carrying Amount	1,239	1,460
Publisher Relationships [Member]	'	'
Finite-Lived Intangible Assets [Line Items]	'	'
Estimated Useful Life	'5 years	'
Gross Carrying Amount	710	710
Accumulated Amortization	260	225
Net Carrying Amount	450	485
Trade Name [Member]	'	'
Finite-Lived Intangible Assets [Line Items]	'	'
Estimated Useful Life	'5 years	'
Gross Carrying Amount	570	570
Accumulated Amortization	209	181
Net Carrying Amount	$361	$389

Goodwill_and_Acquired_Intangib4

Goodwill and Acquired Intangible Assets - Future Estimated Amortization Expense for Intangible Assets (Detail) (USD $)	Mar. 31, 2014	Dec. 31, 2013
In Thousands, unless otherwise specified
Goodwill And Intangible Assets Disclosure [Abstract]	'	'
Remainder of 2014	$1,628	'
2015	1,583	'
2016	470	'
2017	107	'
Net Carrying Amount	$3,788	$4,355

StockBased_Awards_Additional_I

Stock-Based Awards - Additional Information (Detail) (USD $)	3 Months Ended
In Thousands, except Share data, unless otherwise specified	Mar. 31, 2014	Mar. 31, 2013
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]	'	'
Number of share of common stock for each restricted stock unit	1	'
Capitalized stock-based compensation expense	$50	$166
Employees [Member]	'	'
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]	'	'
Percentage of restrictions lapses on stock options after one year and quarterly thereafter	25.00%	'
Period for lapses of stock options thereafter	'36 months	'
Directors [Member]	'	'
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]	'	'
Percentage of restrictions lapses on stock options after one year and quarterly thereafter	33.00%	'
Period for lapses of stock options thereafter	'24 months	'
2012 Inducement Plan [Member]	'	'
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]	'	'
Maximum term of incentive stock options, non-statutory stock options, restricted stock, restricted stock units, stock appreciation rights and other stock-based awards	'7 years	'
Common stock shares reserved for issuance	257,780	'
Shares of common stock available for issuance	77,711	'
Minimum percentage of fair market value of per unit purchase price	100.00%	'
Inducement plan expiration description	'On April 1, 2014, the Company's board of directors voted to terminate the 2012 Inducement Plan. As a result, no additional awards will be granted under this plan.	'
2011 Stock Incentive Plan [Member]	'	'
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]	'	'
Maximum term of incentive stock options, non-statutory stock options, restricted stock, restricted stock units, stock appreciation rights and other stock-based awards	'7 years	'
Common stock shares reserved for issuance	4,200,000	'
Maximum percentage of fair market value of per unit purchase price	100.00%	'
Shares of common stock available for issuance	1,067,381	'
2007 Employee Stock Purchase Plan [Member]	'	'
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]	'	'
Shares of common stock available for issuance	381,135	'
Employee Stock Purchase Plan offering period	'6 months	'
Percentage of closing market price of common stock equals to per share purchase price for offerings	85.00%	'
Service-Based Vesting [Member] | 2012 Revenue RSU [Member]	'	'
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]	'	'
Performance stock units expiration date	31-Mar-17	'
Service-Based Vesting [Member] | 2013 Revenue RSU [Member]	'	'
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]	'	'
Performance stock units expiration date	31-Dec-16	'
Minimum [Member] | Service-Based Vesting [Member] | Restricted Stock Units [Member]	'	'
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]	'	'
Vesting period of restricted awards	'2 years	'
Minimum [Member] | Service-Based Vesting [Member] | 2012 Revenue RSU [Member]	'	'
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]	'	'
Percentage of target shares allowed to vest	25.00%	'
Minimum [Member] | Service-Based Vesting [Member] | 2013 Revenue RSU [Member]	'	'
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]	'	'
Percentage of target shares allowed to vest	50.00%	'
Minimum [Member] | Market-Based Vesting Conditions [Member] | Restricted Stock Units [Member]	'	'
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]	'	'
Percentage of target shares allowed to vest	50.00%	'
Maximum [Member] | Service-Based Vesting [Member] | Restricted Stock Units [Member]	'	'
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]	'	'
Vesting period of restricted awards	'4 years	'
Maximum [Member] | Service-Based Vesting [Member] | 2012 Revenue RSU [Member]	'	'
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]	'	'
Percentage of target shares allowed to vest	100.00%	'
Maximum [Member] | Service-Based Vesting [Member] | 2013 Revenue RSU [Member]	'	'
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]	'	'
Percentage of target shares allowed to vest	125.00%	'
Maximum [Member] | Market-Based Vesting Conditions [Member] | Restricted Stock Units [Member]	'	'
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]	'	'
Percentage of target shares allowed to vest	125.00%	'

StockBased_Awards_Recognized_S

Stock-Based Awards - Recognized Stock-Based Compensation Expense (Detail) (USD $)	3 Months Ended
In Thousands, unless otherwise specified	Mar. 31, 2014	Mar. 31, 2013
Employee Service Share-based Compensation, Allocation of Recognized Period Costs [Line Items]	'	'
Stock-based compensation expense	$3,914	$3,541
Cost of Revenue [Member]	'	'
Employee Service Share-based Compensation, Allocation of Recognized Period Costs [Line Items]	'	'
Stock-based compensation expense	442	399
Research and Development [Member]	'	'
Employee Service Share-based Compensation, Allocation of Recognized Period Costs [Line Items]	'	'
Stock-based compensation expense	1,020	831
Sales and Marketing [Member]	'	'
Employee Service Share-based Compensation, Allocation of Recognized Period Costs [Line Items]	'	'
Stock-based compensation expense	1,032	984
General and Administrative [Member]	'	'
Employee Service Share-based Compensation, Allocation of Recognized Period Costs [Line Items]	'	'
Stock-based compensation expense	$1,420	$1,327

Income_Taxes_Additional_Inform

Income Taxes - Additional Information (Detail) (USD $)	3 Months Ended
In Thousands, unless otherwise specified	Mar. 31, 2014	Mar. 31, 2013	Dec. 31, 2013
Income Tax Disclosure [Abstract]	'	'	'
Income tax (expense) benefit	($328)	$1,988	'
Effect of change in the tax law	'	1,324	'
Net deferred tax assets	10,377	'	10,377
Unrecognized tax benefits	0	'	0
Unrecognized tax benefits, accrued interest or tax penalties	$0	'	$0

Accrued_Expenses_Components_of

Accrued Expenses - Components of Accrued Expenses (Detail) (USD $)	Mar. 31, 2014	Dec. 31, 2013
In Thousands, unless otherwise specified
Payables And Accruals [Abstract]	'	'
Payroll and payroll related	$5,103	$4,106
Licensed software and maintenance	1,197	1,197
Marketing programs	710	575
Other accrued expenses	4,957	5,025
Accrued expenses, total	$11,967	$10,903

Commitments_and_Contingencies_1

Commitments and Contingencies - Additional Information (Detail) (USD $)	3 Months Ended
In Thousands, unless otherwise specified	Mar. 31, 2014	Mar. 31, 2013	Dec. 31, 2013
	Vendor
Operating Leased Assets [Line Items]	'	'	'
Expiration of lease agreement	'Various dates through mid-2017	'	'
Prepaid expenses and other current assets	$10,843	'	$9,175
Amount of contractual commitments with various vendors	19,994	'	'
Letter of credit for the benefit of the landlord	1,300	'	1,300
Cash balance to secure the letter of credit	1,300	'	1,300
Amount payable upon achievement of certain revenue targets	30,000	'	'
Accrual for contingency	0	'	0
Headquarters Space [Member]	'	'	'
Operating Leased Assets [Line Items]	'	'	'
Lease expiration date	22-Sep-22	'	'
Time period for extension option	'10 years	'	'
Number of extension option	1	'	'
Third-Party Hosting Agreements [Member]	'	'	'
Operating Leased Assets [Line Items]	'	'	'
Prepaid rent	771	'	861
Prepaid expenses and other current assets	342	'	360
Other assets	429	'	501
Accrued rent balance	176	'	'
Rent expense	1,063	1,007	'
Number of vendors provide for related services	2	'	'
Third-Party Hosting Agreements [Member] | Accrued Expenses [Member]	'	'	'
Operating Leased Assets [Line Items]	'	'	'
Accrued rent balance included in accrued expenses	10	'	'
Third-Party Hosting Agreements [Member] | Other Long-Term Liabilities [Member]	'	'	'
Operating Leased Assets [Line Items]	'	'	'
Accrued rent balance included in other long-term liabilities	166	'	173
Sales and Support Office [Member]	'	'	'
Operating Leased Assets [Line Items]	'	'	'
Time period for extension option	'3 years	'	'
Number of extension option	3	'	'
Expiration of lease agreement	'April 2019	'	'
General Office [Member]	'	'	'
Operating Leased Assets [Line Items]	'	'	'
Expiration of lease agreement	'Various dates through 2018	'	'
Office Leases [Member]	'	'	'
Operating Leased Assets [Line Items]	'	'	'
Prepaid rent	468	'	634
Prepaid expenses and other current assets	198	'	128
Other assets	270	'	506
Accrued rent balance	2,159	'	2,239
Rent expense	2,320	1,970	'
Office Leases [Member] | Accrued Expenses [Member]	'	'	'
Operating Leased Assets [Line Items]	'	'	'
Accrued rent balance included in accrued expenses	363	'	351
Office Leases [Member] | Other Long-Term Liabilities [Member]	'	'	'
Operating Leased Assets [Line Items]	'	'	'
Accrued rent balance included in other long-term liabilities	$1,796	'	$1,888

Commitments_and_Contingencies_2

Commitments and Contingencies - Future Minimum Lease Payments under Leases and Agreements (Detail) (USD $)	Mar. 31, 2014
In Thousands, unless otherwise specified
Office Leases [Member]	'
Operating Leased Assets [Line Items]	'
Remainder of 2014	$6,408
2015	9,238
2016	10,194
2017	10,153
2018	9,747
Thereafter	30,954
Total	76,694
Third-Party Hosting Agreements [Member]	'
Operating Leased Assets [Line Items]	'
Remainder of 2014	2,875
2015	3,938
2016	4,049
2017	775
Total	$11,637

401k_Savings_Plan_Additional_I

401(k) Savings Plan - Additional Information (Detail) (USD $)	3 Months Ended
In Thousands, unless otherwise specified	Mar. 31, 2014	Mar. 31, 2013
Defined Benefit Plan Disclosure [Line Items]	'	'
Contribution by employer to 401 (k) Savings Plan	$863	$664
Employee's Contributions up to 3% [Member]	'	'
Defined Benefit Plan Disclosure [Line Items]	'	'
Employer matching contribution, percent	100.00%	100.00%
Employee's Contributions Between 3% and 5% [Member]	'	'
Defined Benefit Plan Disclosure [Line Items]	'	'
Employer matching contribution, percent	50.00%	50.00%
100% of Matching Contribution [Member]	'	'
Defined Benefit Plan Disclosure [Line Items]	'	'
Percentage of the employee's compensation	3.00%	3.00%
50% of Matching Contribution [Member]	'	'
Defined Benefit Plan Disclosure [Line Items]	'	'
Percentage of the employee's compensation	5.00%	5.00%
50% of Matching Contribution [Member] | Minimum [Member]	'	'
Defined Benefit Plan Disclosure [Line Items]	'	'
Percentage of the employee's compensation	3.00%	3.00%