ChannelAdvisor (ECOM) 10-K 27 Feb 14 2013 FY Annual report Financial data

Document_and_Entity_Informatio

Document and Entity Information (USD $)	12 Months Ended
	Dec. 31, 2013	Jan. 31, 2014	Jun. 28, 2013
Document Document And Entity Information [Abstract]	'	'	'
Entity Registrant Name	'CHANNELADVISOR CORP	'	'
Entity Central Index Key	'0001169652	'	'
Current Fiscal Year End Date	'--12-31	'	'
Entity Filer Category	'Non-accelerated Filer	'	'
Document Type	'10-K	'	'
Document Period End Date	31-Dec-13	'	'
Document Fiscal Period Focus	'FY	'	'
Document Fiscal Year Focus	'2013	'	'
Amendment Flag	'false	'	'
Entity Common Stock, Shares Outstanding	'	24,326,101	'
Entity Well-known Seasoned Issuer	'No	'	'
Entity Voluntary Filers	'No	'	'
Entity Current Reporting Status	'Yes	'	'
Entity Public Float	'	'	$159,748,028

Consolidated_Balance_Sheets

Consolidated Balance Sheets (USD $)	Dec. 31, 2013	Dec. 31, 2012
In Thousands, unless otherwise specified
Assets	'	'
Cash and cash equivalents	$104,406	$10,865
Accounts receivable, net of allowance of $561 and $191 as of December 31, 2013 and 2012, respectively	13,951	9,571
Prepaid expenses and other current assets	3,571	2,589
Total current assets	121,928	23,025
Property and equipment, net	9,088	4,315
Goodwill	16,106	16,106
Intangible assets, net	670	1,245
Restricted cash	685	687
Other assets	309	2,644
Total assets	148,786	48,022
Liabilities, redeemable convertible preferred stock and stockholders' equity (deficit)	'	'
Accounts payable	4,237	1,269
Accrued expenses	7,492	4,650
Deferred revenue	14,093	9,750
Current portion of long-term debt	0	3,370
Other current liabilities	1,723	980
Total current liabilities	27,545	20,019
Long-term debt, net of current portion	0	7,602
Series A and Series C warrants liability	0	3,235
Long-term capital leases, net of current portion	1,558	1,136
Other long-term liabilities	1,903	1,714
Total liabilities	31,006	33,706
Commitments and contingencies (Note 5)	'	'
Redeemable convertible preferred stock:	'	'
Redeemable convertible preferred stock	0	90,495
Stockholders' equity (deficit):	'	'
Preferred stock, $0.001 par value, 5,000,000 and 0 shares authorized, no shares issued and outstanding as of December 31, 2013 and 2012, respectively	0	0
Common stock, $0.001 par value, 100,000,000 and 303,500,000 shares authorized, 23,643,872 and 1,240,193 shares issued and outstanding as of December 31, 2013 and 2012, respectively	24	1
Additional paid-in capital	218,330	3,584
Accumulated other comprehensive loss	-471	-289
Accumulated deficit	-100,103	-79,475
Total stockholders' equity (deficit)	117,780	-76,179
Total liabilities, redeemable convertible preferred stock and stockholders' equity (deficit)	148,786	48,022
Redeemable Convertible Series A Preferred Stock [Member]	'	'
Redeemable convertible preferred stock:	'	'
Redeemable convertible preferred stock	0	18,887
Redeemable Convertible Series B Preferred Stock [Member]	'	'
Redeemable convertible preferred stock:	'	'
Redeemable convertible preferred stock	0	18,000
Redeemable Convertible Series B-1 Preferred Stock [Member]	'	'
Redeemable convertible preferred stock:	'	'
Redeemable convertible preferred stock	0	3,000
Redeemable Convertible Series C Preferred Stock [Member]	'	'
Redeemable convertible preferred stock:	'	'
Redeemable convertible preferred stock	$0	$50,608

Consolidated_Balance_Sheets_Pa

Consolidated Balance Sheets (Parenthetical) (USD $)	Dec. 31, 2013	Dec. 31, 2012	Dec. 31, 2013	Dec. 31, 2012	Dec. 31, 2013	Dec. 31, 2012	Dec. 31, 2013	Dec. 31, 2012	Dec. 31, 2013	Dec. 31, 2012
In Thousands, except Share data, unless otherwise specified			Redeemable Convertible Series A Preferred Stock [Member]	Redeemable Convertible Series A Preferred Stock [Member]	Redeemable Convertible Series B Preferred Stock [Member]	Redeemable Convertible Series B Preferred Stock [Member]	Redeemable Convertible Series B-1 Preferred Stock [Member]	Redeemable Convertible Series B-1 Preferred Stock [Member]	Redeemable Convertible Series C Preferred Stock [Member]	Redeemable Convertible Series C Preferred Stock [Member]
Allowance for doubtful accounts receivable, current	$561	$191	'	'	'	'	'	'	'	'
Preferred stock, par value	$0.00	$0	'	'	'	'	'	'	'	'
Preferred stock, shares authorized	5,000,000	0	'	'	'	'	'	'	'	'
Preferred stock, shares issued	0	0	'	'	'	'	'	'	'	'
Preferred stock, shares outstanding	0	0	'	'	'	'	'	'	'	'
Redeemable convertible preferred stock, par value	'	'	$0	$0.00	$0	$0.00	$0	$0.00	$0	$0.00
Redeemable convertible preferred stock, shares authorized	'	'	0	94,069,763	0	40,641,227	0	5,660,378	0	80,000,000
Redeemable convertible preferred stock, shares issued	'	'	0	93,821,393	0	40,641,227	0	5,660,378	0	73,880,351
Redeemable convertible preferred stock, shares outstanding	'	'	0	93,821,393	0	40,641,227	0	5,660,378	0	73,880,351
Common stock, par value	$0.00	$0.00	'	'	'	'	'	'	'	'
Common stock, shares authorized	100,000,000	303,500,000	'	'	'	'	'	'	'	'
Common stock, shares issued	23,643,872	1,240,193	'	'	'	'	'	'	'	'
Common stock, shares outstanding	23,643,872	1,240,193	'	'	'	'	'	'	'	'

Consolidated_Statements_of_Ope

Consolidated Statements of Operations (USD $)	12 Months Ended
In Thousands, except Share data, unless otherwise specified	Dec. 31, 2013	Dec. 31, 2012	Dec. 31, 2011
Income Statement [Abstract]	'	'	'
Revenue	$68,004	$53,587	$43,570
Cost of revenue	18,088	14,749	12,248
Gross profit	49,916	38,838	31,322
Operating expenses:	'	'	'
Sales and marketing	37,458	24,326	19,106
Research and development	12,669	10,109	8,842
General and administrative	14,154	8,252	6,551
Total operating expenses	64,281	42,687	34,499
Loss from operations	-14,365	-3,849	-3,177
Other (expense) income:	'	'	'
Loss on extinguishment of debt	-3,112	0	0
Interest expense, net	-2,960	-1,185	-642
Other income, net	12	31	6
Total other (expense) income	-6,060	-1,154	-636
Loss before income taxes	-20,425	-5,003	-3,813
Income tax expense (benefit)	203	-70	51
Net loss	($20,628)	($4,933)	($3,864)
Net loss per share:	'	'	'
Basic and diluted (in dollars per share)	($1.51)	($4.23)	($3.45)
Weighted average common shares outstanding:	'	'	'
Basic and diluted (in shares)	13,695,804	1,164,942	1,120,902

Consolidated_Statements_of_Com

Consolidated Statements of Comprehensive Loss (USD $)	12 Months Ended
In Thousands, unless otherwise specified	Dec. 31, 2013	Dec. 31, 2012	Dec. 31, 2011
Statement of Comprehensive Income [Abstract]	'	'	'
Net loss	($20,628)	($4,933)	($3,864)
Other comprehensive loss:	'	'	'
Foreign currency translation adjustments	-182	-45	70
Total comprehensive loss	($20,810)	($4,978)	($3,794)

Consolidated_Statement_of_Chan

Consolidated Statement of Changes in Stockholders' (Deficit) Equity (USD $)	Total	Common Stock [Member]	Additional Paid-In Capital [Member]	Accumulated Other Comprehensive Loss [Member]	Accumulated Deficit [Member]
In Thousands, except Share data, unless otherwise specified
Balance, amount at Dec. 31, 2010	($68,307)	$1	$2,684	($314)	($70,678)
Balance, shares at Dec. 31, 2010	'	1,069,305	'	'	'
Increase (Decrease) in Stockholders' Equity [Roll Forward]	'	'	'	'	'
Conversion of redeemable convertible preferred stock to common stock, amount	0	'	'	'	'
Exercise of stock options, amount	98	'	98	'	'
Exercise of stock options, shares	'	71,264	'	'	'
Accretion of issuance costs on redeemable convertible preferred stock	-50	'	-50	'	'
Stock-based compensation expense	200	'	200	'	'
Net loss	-3,864	'	'	'	-3,864
Foreign currency translation adjustments	70	'	'	70	'
Balance, amount at Dec. 31, 2011	-71,853	1	2,932	-244	-74,542
Balance, shares at Dec. 31, 2011	'	1,140,569	'	'	'
Increase (Decrease) in Stockholders' Equity [Roll Forward]	'	'	'	'	'
Conversion of redeemable convertible preferred stock to common stock, amount	0	'	'	'	'
Repurchase and retirement of common stock, amount	-193	'	-193	'	'
Repurchase and retirement of common stock, shares	'	-25,000	'	'	'
Exercise of stock options, amount	222	'	222	'	'
Exercise of stock options, shares	'	124,624	'	'	'
Accretion of issuance costs on redeemable convertible preferred stock	-15	'	-15	'	'
Stock-based compensation expense	638	'	638	'	'
Net loss	-4,933	'	'	'	-4,933
Foreign currency translation adjustments	-45	'	'	-45	'
Balance, amount at Dec. 31, 2012	-76,179	1	3,584	-289	-79,475
Balance, shares at Dec. 31, 2012	'	1,240,193	'	'	'
Increase (Decrease) in Stockholders' Equity [Roll Forward]	'	'	'	'	'
Conversion of redeemable convertible preferred stock to common stock, amount	91,150	13	91,137	'	'
Conversion of redeemable convertible preferred stock to common stock, shares	'	13,401,499	'	'	'
Conversion of redeemable convertible preferred stock warrants to common stock warrants	3,632	'	3,632	'	'
Issuance of common stock from public offerings, net of issuance costs, amount	113,848	8	113,840	'	'
Issuance of common stock from public offerings, net of issuance costs, shares	'	7,612,500	'	'	'
Exercise of common stock warrants, amount	1,592	1	1,591	'	'
Exercise of common stock warrants, shares	'	662,362	'	'	'
Exercise of stock options, amount	2,448	1	2,447	'	'
Exercise of stock options, shares	727,318	727,318	'	'	'
Accretion of issuance costs on redeemable convertible preferred stock	0	'	'	'	'
Stock-based compensation expense	2,099	'	2,099	'	'
Net loss	-20,628	'	'	'	-20,628
Foreign currency translation adjustments	-182	'	'	-182	'
Balance, amount at Dec. 31, 2013	$117,780	$24	$218,330	($471)	($100,103)
Balance, shares at Dec. 31, 2013	'	23,643,872	'	'	'

Consolidated_Statements_of_Cas

Consolidated Statements of Cash Flows (USD $)	12 Months Ended
In Thousands, unless otherwise specified	Dec. 31, 2013	Dec. 31, 2012	Dec. 31, 2011
Cash flows from operating activities	'	'	'
Net loss	($20,628)	($4,933)	($3,864)
Adjustments to reconcile net loss to net cash and cash equivalents (used in) provided by operating activities:	'	'	'
Depreciation and amortization	3,722	2,903	2,061
Loss on extinguishment of debt	3,112	0	0
Bad debt expense	527	162	71
Deferred income taxes	-12	30	49
Change in fair value of preferred stock warrants	1,052	5	261
Accretion of debt discount	547	372	9
Non-cash stock-based compensation expense	2,099	638	200
Change in lease incentive obligation	-21	-21	114
Amortization of debt issuance costs	38	57	29
Change in deferred rent	51	544	302
Gain on disposal of furniture and equipment	0	0	-1
Changes in assets and liabilities:	'	'	'
Accounts receivable	-4,917	-1,966	-1,537
Prepaid expenses and other assets	-1,026	-1,102	-809
Restricted cash	-1	199	0
Accounts payable and accrued expenses	5,672	381	1,365
Deferred revenue	4,471	3,922	1,911
Net cash and cash equivalents (used in) provided by operating activities	-5,314	1,191	161
Cash flows from investing activities	'	'	'
Purchases of property and equipment	-3,711	-1,930	-1,723
Payment of internal-use software development costs	-1,507	-164	0
Net cash and cash equivalents used in investing activities	-5,218	-2,094	-1,723
Cash flows from financing activities	'	'	'
Proceeds from issuance of common stock, net of underwriting discounts and commissions	118,463	0	0
Proceeds from issuance of debt, net of debt issuance costs	0	9,873	1,000
Repayment of debt and capital leases	-14,230	-1,548	-1,541
Payment of debt extinguishment costs	-1,200	0	0
Payment of deferred offering costs	-2,909	-1,548	0
Proceeds from exercise of common stock warrants	1,592	0	0
Proceeds from exercise of stock options	2,448	222	98
Repurchase and retirement of common stock	0	-193	0
Net cash and cash equivalents provided by (used in) financing activities	104,164	6,806	-443
Effect of currency exchange rate changes on cash and cash equivalents	-91	-36	64
Net increase (decrease) in cash and cash equivalents	93,541	5,867	-1,941
Cash and Cash Equivalents, beginning of period	10,865	4,998	6,939
Cash and Cash Equivalents, end of period	104,406	10,865	4,998
Supplemental disclosure of cash flow information	'	'	'
Cash paid for interest	1,334	614	376
Cash paid for income taxes, net	92	64	18
Supplemental disclosure of noncash investing and financing activities	'	'	'
Conversion of redeemable convertible preferred stock to common stock	91,150	0	0
Reclassification of warrant liability to equity	3,632	0	0
Accretion of issuance costs on Preferred Stock	0	15	50
Deferred offering costs included in accounts payable and accrued expenses	73	743	0
Accrued capital expenditures	627	0	433
Capital lease obligations entered into for the purchase of fixed assets	$1,454	$2,014	$98

Description_of_the_Business

Description of the Business	12 Months Ended
	Dec. 31, 2013
Organization, Consolidation and Presentation of Financial Statements [Abstract]	'
Description of the Business	'
	Description of the Business
	ChannelAdvisor Corporation (“ChannelAdvisor” or the “Company”) was incorporated in the state of Delaware and capitalized in June 2001. The Company began operations in July 2001. ChannelAdvisor is a provider of software-as-a-service ("SaaS") solutions that allow retailers and manufacturers to integrate, manage and monitor their merchandise sales across hundreds of online channels. The Company is headquartered in Morrisville, North Carolina and has offices in England, Ireland, Germany, Australia, Hong Kong and Brazil.

Significant_Accounting_Policie

Significant Accounting Policies	12 Months Ended
	Dec. 31, 2013
Accounting Policies [Abstract]	'
Significant Accounting Policies	'
	Significant Accounting Policies
	Principles of Consolidation
	The accompanying consolidated financial statements include the accounts of the Company and its wholly-owned subsidiaries. All intercompany accounts and transactions have been eliminated in consolidation.
	Reverse Stock Split
	On May 9, 2013, the Company’s amended and restated certificate of incorporation was amended to effect a 1-for-16 reverse stock split of its outstanding common stock. The reverse stock split did not cause an adjustment to the par value or the authorized shares of the common stock. As a result of the reverse stock split, the share amounts under the Company’s employee incentive plan and common stock warrants were automatically adjusted. The accompanying consolidated financial statements and notes to the consolidated financial statements give retroactive effect to the reverse stock split for all periods presented.
	Public Offerings
	On May 29, 2013, the Company closed the initial public offering ("IPO") of its common stock pursuant to a registration statement on Form S-1 that was declared effective on May 22, 2013. In the IPO, the Company sold an aggregate of 6,612,500 shares of common stock, including the full exercise of the underwriters’ option to purchase additional shares, at a public offering price of $14.00 per share. Net proceeds were approximately $82.0 million, after deducting underwriting discounts and commissions of $6.5 million and offering expenses of $4.1 million. Costs directly associated with the IPO were capitalized and recorded as deferred offering costs prior to the closing of the IPO. These costs were recorded as a reduction of the IPO proceeds received in calculating the amount to be recorded in additional paid-in capital.
	Upon the closing of the IPO, certain Series C warrants that would otherwise have expired were automatically net exercised into 206,038 shares of redeemable convertible preferred stock. All then-outstanding shares of the Company’s redeemable convertible preferred stock were automatically converted into 13,401,499 shares of common stock. The remaining warrants to purchase redeemable convertible preferred stock outstanding as of the closing of the IPO automatically converted into warrants to purchase an aggregate of 216,491 shares of common stock, and the preferred stock warrant liability was reclassified to additional paid-in capital as of May 29, 2013.
	In addition, upon the closing of the IPO, the Company’s certificate of incorporation was amended and restated to authorize 5,000,000 shares of undesignated preferred stock and 100,000,000 shares of common stock.
	On November 12, 2013, the Company closed a registered public offering of its common stock pursuant to a registration statement on Form S-1 that was declared effective on November 5, 2013. In the registered public offering, the Company sold and issued 1,000,000 shares of common stock at a public offering price of $34.00 per share. Net proceeds were approximately $31.9 million, after deducting underwriting discounts and commissions of $1.6 million and offering expenses of $0.5 million.
	Recently Adopted Accounting Pronouncements
	The Company has reviewed accounting pronouncements that were issued as of December 31, 2013 and does not believe that these pronouncements will have a material impact on its financial position or results of operations.
	Use of Estimates
	The preparation of financial statements in conformity with United States generally accepted accounting principles (“U.S. GAAP”) requires management to make estimates and assumptions that affect the amounts reported in the consolidated financial statements and accompanying notes. Actual results could differ from those estimates.
	On an ongoing basis, the Company evaluates its estimates, including those related to the accounts receivable allowance, the useful lives of long-lived assets and other intangible assets, assumptions used for purposes of determining stock-based compensation, income taxes, and the fair value of the Series A and Series C warrants and the Company’s common stock prior to the closing of the IPO, among others. The Company bases its estimates on historical experience and on various other assumptions that it believes to be reasonable, the results of which form the basis for making judgments about the carrying value of assets and liabilities.
	Cash and Cash Equivalents
	The Company considers all highly liquid investments maturing within ninety days or less at the time of purchase to be cash equivalents. Cash and cash equivalents are comprised of cash and money market funds. Due to the short-term nature and liquidity of these financial instruments, the carrying value of these assets approximates fair value.
	Restricted Cash
	Restricted cash represents cash that is not readily available for general purpose cash needs. Restricted cash is classified as a long-term asset based on the timing and nature of when and how the cash is expected to be used or when the restrictions are expected to lapse.
	As of December 31, 2013 and 2012, the Company had restricted cash of $0.7 million related to its operations in the United States. Of this amount, $0.6 million has been used as collateral for potential chargebacks resulting from the Company’s processing of customers’ credit cards as of December 31, 2013 and 2012. The remaining restricted cash at December 31, 2013 and 2012 relates to cash set aside as a requirement for leasing the Company’s operating sites or for miscellaneous banking activity as required by the Company’s banks.
	In addition, certain of the Company's foreign subsidiaries had nominal restricted cash balances as of December 31, 2013 and 2012.
	Revenue Recognition and Deferred Revenue
	The majority of the Company’s revenue is derived from subscription fees paid by customers for access to and usage of the Company’s cloud-based SaaS platform for a specified period of time, which is typically one year. A portion of the subscription fee is typically fixed and is based on a specified minimum amount of gross merchandise value (“GMV”) that a customer expects to process through the Company’s platform over the contract term. The remaining portion of the subscription fee is variable and is based on a specified percentage of GMV processed through the Company’s platform in excess of the customer’s specified minimum GMV amount. In addition, other sources of revenue consist primarily of implementation fees, which may include fees for providing launch assistance and training. The Company recognizes revenue when there is persuasive evidence of an arrangement, the service has been provided to the customer, the collection of the fee is reasonably assured and the amount of the fee to be paid by the customer is fixed or determinable. The Company’s contractual arrangements include performance, termination and cancellation provisions, but do not provide for refunds. Customers do not have the contractual right to take possession of the Company’s software at any time.
	The Company’s arrangements generally contain multiple elements comprised of subscription and implementation services. The Company evaluates each element in an arrangement to determine whether it represents a separate unit of accounting. An element constitutes a separate unit of accounting when the delivered item has standalone value and delivery of the undelivered element is probable and within the Company’s control. The Company’s implementation services are not sold separately from the subscription and there is no alternative use for them. As such, the Company has determined the implementation services do not have standalone value. Accordingly, subscription and implementation services are combined and recognized as a single unit of accounting.
	The Company generally recognizes the fixed portion of subscription fees and implementation fees ratably over the contract term. Recognition begins when the customer has access to the Company’s platform and transactions can be processed, provided all other revenue recognition criteria have been met. Some customers elect a managed-service solution and contract with the Company to manage some or all aspects of the Company’s SaaS solutions on the customer’s behalf for a specified period of time, which is typically one year. Under these managed-service arrangements, customer transactions cannot be processed through the Company’s platform until the completion of the implementation services. As such, revenue is contingent upon the Company’s completion of the implementation services and recognition commences when transactions can be processed on the Company’s platform, provided all other revenue recognition criteria have been satisfied. At that time, the Company recognizes a pro-rata portion of the fees earned since the inception of the arrangement. The balance of the fees is recognized ratably over the remaining contract term.
	The Company recognizes the variable portion of subscription fee revenue in the period in which the related GMV is processed, provided all other revenue recognition criteria have been met.
	Sales taxes collected from customers and remitted to government authorities are excluded from revenue.
	Deferred revenue represents the unearned portion of fixed subscription fees and implementation fees. Deferred amounts will generally be recognized within one year. Those amounts that are expected to be recognized in greater than one year are recorded in other long-term liabilities in the accompanying consolidated balance sheets.
	Sales Commissions
	Sales commissions are expensed when the related subscription agreement is executed by the customer.
	Cost of Revenue
	Cost of revenue primarily consists of personnel and related costs, including salaries, bonuses, payroll taxes and stock compensation, co-location facility costs for the Company’s data centers, depreciation expense for computer equipment directly associated with generating revenue, credit card transaction fees and infrastructure maintenance costs. In addition, the Company allocates a portion of overhead, such as rent, additional depreciation and amortization and employee benefits costs, to cost of revenue based on headcount.
	Fair Value of Financial Instruments
	The carrying amounts of certain of the Company’s financial instruments, including cash and cash equivalents, accounts receivable, accounts payable and accrued expenses, approximate their respective fair values due to their short-term nature. Prior to the closing of the IPO on May 29, 2013, at which time certain Series C warrants were automatically net exercised and the remaining warrants converted into common stock warrants, the Company's Series A and Series C warrants were recorded at fair value.
	The Company uses a three-tier fair value hierarchy to classify and disclose all assets and liabilities measured at fair value on a recurring basis, as well as assets and liabilities measured at fair value on a non-recurring basis, in periods subsequent to their initial measurement. The hierarchy requires the Company to use observable inputs when available, and to minimize the use of unobservable inputs when determining fair value. The three tiers are defined as follows:
	•Level 1. Observable inputs based on unadjusted quoted prices in active markets for identical assets or liabilities;
	•Level 2. Inputs, other than quoted prices in active markets, that are observable either directly or indirectly; and
	•Level 3. Unobservable inputs for which there is little or no market data, which require the Company to develop its own assumptions.
	Assets and Liabilities Measured at Fair Value on a Recurring Basis
	The Company evaluates its financial assets and liabilities subject to fair value measurements on a recurring basis to determine the appropriate level in which to classify them for each reporting period. This determination requires significant judgments to be made. The following table summarizes the conclusions reached as of December 31, 2012 (in thousands):
		Balance as of				Level 1				Level 2			Level 3
		December 31,
		2012
	Liabilities:
	Series A warrants(1)	$	88			$	—			$	—		$	88
	Series C warrants(1)	3,147				—				—			3,147
		$	3,235			$	—			$	—		$	3,235
	_______________________
	(1) In order to determine the fair value of the redeemable convertible preferred stock warrants, the Company used a hybrid of the probability-weighted expected return method (“PWERM”) and the option pricing model ("OPM"), collectively referred to as the “Hybrid Method,” for the year ended December 31, 2012. The Hybrid Method is a PWERM model in which one of the valuation scenarios is modeled using an OPM.
	Significant inputs for the OPM included an estimate of the fair value of the Series A and Series C redeemable convertible preferred stock, the remaining contractual life of the warrants, an estimate of the timing of a liquidity event, a risk-free rate of interest and an estimate of the Company’s stock volatility using the volatilities of guideline peer companies. Significant inputs for the PWERM included an estimate of the Company’s equity value, a weighted average cost of capital and an estimated probability and timing for each valuation scenario.
	Assets and Liabilities Measured at Fair Value on a Recurring Basis Using Significant Unobservable Inputs
	The following table presents the changes in the Company’s Level 3 instruments measured at fair value on a recurring basis during the years ended December 31, 2013, 2012 and 2011 (in thousands):
		Series A												Series C
			2013				2012				2011			2013			2012			2011
	Balance as of January 1		$	88			$	113			$	63		$	3,147		$	479		$	268
	Issuance of Series C warrant		—				—				—			—			2,705			—
	Cashless exercise of warrants		(166		)		(67		)		—			(489		)	—			—
	Change in fair value of warrant liability		78				42				50			974			(37		)	211
	Reclassification of warrant liability to equity		—				—				—			(3,632		)	—			—
	Balance as of December 31		$	—			$	88			$	113		$	—		$	3,147		$	479
	Concentration of Credit Risk
	Financial instruments that subject the Company to significant concentrations of credit risk consist primarily of cash and cash equivalents and accounts receivable. All of the Company’s cash and cash equivalents are held at financial institutions that management believes to be of high credit quality. The Company’s cash and cash equivalent accounts exceed federally insured limits. The Company has not experienced any losses on cash and cash equivalents to date. To manage accounts receivable risk, the Company maintains an allowance for doubtful accounts.
	The Company did not have any customers that individually comprised a significant concentration of its accounts receivable as of December 31, 2013 and 2012, or a significant concentration of its revenue for the years ended December 31, 2013, 2012 and 2011.
Accounts Receivable and Allowance for Doubtful Accounts
The Company extends credit to customers without requiring collateral. Accounts receivable are stated at realizable value, net of an allowance for doubtful accounts. The Company utilizes the allowance method to provide for doubtful accounts based on management’s evaluation of the collectability of amounts due. The Company’s estimate is based on historical collection experience and a review of the current status of accounts receivable. Historically, actual write-offs for uncollectible accounts have not significantly differed from the Company’s estimates.
The following table presents the changes in the Company’s allowance for doubtful accounts during the years ended December 31, 2013, 2012 and 2011 (in thousands):
	Balance at				Additions				Deductions			Balance at
	Beginning				Charged To							End of
	of Period				Expense/							Period
					Against
					Revenue
Allowance for doubtful accounts:
Year ended December 31, 2013	$	191			$	594			$	(224	)	$	561
Year ended December 31, 2012	115				222				(146		)	191
Year ended December 31, 2011	192				202				(279		)	115
Other Receivables
Under certain customer arrangements, the Company collects and remits monthly activity-based fees incurred on specific channels on the customers’ behalf. The Company records the amounts due from customers as a result of these arrangements as other receivables.
Other receivables of $1.7 million and $1.5 million are included in prepaid expenses and other current assets on the consolidated balance sheets as of December 31, 2013 and 2012, respectively.
Deferred Offering Costs
Deferred offering costs of $2.3 million are included in other assets on the consolidated balance sheet as of December 31, 2012. Upon the completion of the IPO, these amounts were offset against the proceeds of the offering and included in stockholders’ equity (deficit). There were no amounts capitalized as of December 31, 2013.
Property and Equipment
Property and equipment are recorded at cost. Expenditures for major additions and improvements are capitalized. Depreciation and amortization is provided over the estimated useful lives of the related assets using the straight-line method.
The estimated useful lives for significant property and equipment categories are generally as follows:
Purchased software, including internal-use software	3 years
Computer hardware	3 years
Furniture and office equipment	3 to 5 years
Leasehold improvements	Lesser of remaining lease term or useful life
Repairs and maintenance costs are expensed as incurred.
Identifiable Intangible Assets
The Company acquired intangible assets in connection with its business acquisitions. These assets were recorded at their estimated fair values at the acquisition date and are being amortized over their respective estimated useful lives using the straight-line method. The estimated useful lives used in computing amortization are as follows:
Customer relationships	5 to 8 years
Proprietary software	8 years
Trade name	5 years
Impairment of Long-Lived Assets
The Company reviews long-lived assets and definite-lived intangible assets for impairment whenever events or changes in circumstances indicate the carrying amount of an asset may not be recoverable. Recoverability of the long-lived asset is measured by a comparison of the carrying amount of the asset or asset group to future undiscounted net cash flows expected to be generated by the asset or asset group. If such assets are not recoverable, the impairment to be recognized, if any, is measured by the amount by which the carrying amount of the assets exceeds the estimated fair value of the assets or asset group. Assets held for sale are reported at the lower of the carrying amount or fair value, less costs to sell. As of December 31, 2013 and 2012, management does not believe any long-lived assets are impaired and has not identified any assets as being held for sale.
Goodwill
Goodwill represents the excess of the aggregate of the fair value of consideration transferred in a business combination over the fair value of assets acquired, net of liabilities assumed. Goodwill is not amortized, but is subject to an annual impairment test. The Company tests goodwill for impairment annually on December 31, or more frequently if events or changes in business circumstances indicate the asset might be impaired.
The Company has determined that it has a single, entity-wide reporting unit. Prior to the IPO, the Company determined the fair value of its reporting unit primarily using a discounted cash flow analysis, which required significant assumptions and estimates about future operations. Significant judgments inherent in this analysis included the determination of an appropriate discount rate, estimated terminal value and the amount and timing of expected future cash flows. Subsequent to the IPO, the Company uses market capitalization to determine the fair value of its entity-wide reporting unit.
During the year ended December 31, 2012, the Company adopted ASU 2011-08, “Intangibles — Goodwill and Other (Topic 350): Testing Goodwill for Impairment,” which gives entities testing goodwill for impairment the option of performing a qualitative assessment to determine whether it is more likely than not that the fair value of a reporting unit is less than its carrying amount. During this assessment, the Company first assesses qualitative factors to determine whether it is more likely than not that the fair value of its reporting unit is less than its carrying amount. Qualitative factors considered include, but are not limited to, macroeconomic conditions, industry and market conditions, company-specific events, changes in circumstances and after-tax cash flows. As of December 31, 2013, the Company determined that its reporting unit did not have a carrying value that was more likely than not to exceed its fair value.
If the qualitative factors indicate that it is more likely than not that the fair value of the reporting unit is less than its carrying amount, the Company would test goodwill for impairment at the reporting unit level using a two-step approach. The first step is to compare the fair value of the reporting unit to the carrying value of the net assets assigned to the reporting unit. If the fair value of the reporting unit is greater than the carrying value of the net assets assigned to the reporting unit, the assigned goodwill is not considered impaired. If the fair value is less than the reporting unit’s carrying value, step two is performed to measure the amount of the impairment, if any. In the second step, the fair value of goodwill is determined by deducting the fair value of the reporting unit’s identifiable assets and liabilities from the fair value of the reporting unit as a whole, as if the reporting unit had just been acquired and the fair value was being initially allocated. If the carrying value of goodwill exceeds the implied fair value, an impairment charge would be recorded in the period the determination is made.
As a result of the Company’s annual impairment test as of December 31, 2013 and 2012, goodwill was not considered impaired and, as such, no impairment charges were recorded.
Advertising Costs
The Company expenses advertising costs as incurred. The amount expensed during the years ended December 31, 2013, 2012 and 2011 was $4.6 million, $2.1 million and $1.9 million, respectively.
Software Development Costs
The Company capitalizes certain internal-use software development costs, consisting primarily of direct labor associated with creating the internally developed software and third-party consulting fees associated with implementing software purchased for internal use. Software development projects generally include three stages: the preliminary project stage (in which all costs are expensed as incurred), the application development stage (in which certain costs are capitalized) and the post-implementation/operation stage (in which all costs are expensed as incurred). The costs incurred during the application development stage primarily include the costs of designing the application, coding and testing of the system. Capitalized costs are amortized using the straight-line method over the estimated useful life of the software once it is ready for its intended use.
Software development costs of $0.3 million and $0.2 million related to creating internally developed software and implementing software purchased for internal use were capitalized during the years ended December 31, 2013 and 2012, respectively, and are included in property and equipment in the accompanying consolidated balance sheets. Amortization expense related to this capitalized internally developed software was $0.1 million and $20,000 for the years ended December 31, 2013 and 2012, respectively, and is included in cost of revenue or general and administrative expense in the accompanying consolidated statements of operations. The net book value of capitalized internally developed software was $0.3 million and $0.1 million at December 31, 2013 and 2012, respectively.
Software development costs of $1.8 million related to configuring and implementing hosted third-party software applications that the Company will use in its business operations were capitalized during the year ended December 31, 2013 and are included in property and equipment in the accompanying consolidated balance sheets. Amortization expense related to these capitalized assets was $0.1 million for the year ended December 31, 2013 and is included in general and administrative expense in the accompanying consolidated statements of operations. The net book value of these capitalized assets was $1.7 million and $0 as of December 31, 2013 and 2012, respectively.
During the year ended December 31, 2011, the costs incurred during the application development stage were not significant and were charged to operations in the accompanying consolidated statement of operations.
Income Taxes
Income taxes are accounted for under the asset and liability method of accounting. Deferred tax assets and liabilities are recognized for the future tax consequences attributable to differences between the financial statement carrying amounts of existing assets and liabilities and their respective tax bases, as well as for operating loss and tax credit carryforwards. Deferred tax assets and liabilities are measured using enacted tax rates expected to apply to taxable income in the years in which those temporary differences are expected to be recovered or settled. The effect on deferred tax assets and liabilities of a change in tax rates is recognized in the results of operations in the period that includes the enactment date. The measurement of a deferred tax asset is reduced, if necessary, by a valuation allowance if it is more likely than not that some portion or all of the deferred tax asset will not be realized.
The Company applies the accounting guidance for uncertainties in income taxes, which prescribes a recognition threshold and measurement process for recording uncertain tax positions taken, or expected to be taken, in a tax return in the financial statements. Additionally, the guidance also prescribes the treatment for the derecognition, classification, accounting in interim periods and disclosure requirements for uncertain tax positions. The Company accrues for the estimated amount of taxes for uncertain tax positions if it is more likely than not that the Company would be required to pay such additional taxes. An uncertain tax position will be recognized if it is more likely than not to be sustained. The Company did not have any accrued interest or penalties associated with unrecognized tax positions as of December 31, 2013 and 2012.
Foreign Currency Translation
The functional currency of the Company’s non-U.S. operations is the local currency. Assets and liabilities denominated in foreign currencies are translated into U.S. dollars at exchange rates prevailing at the balance sheet dates. Revenue and expenses are translated into U.S. dollars using the average rates of exchange prevailing during the period. Gains or losses resulting from the translation of assets and liabilities are included as a component of accumulated other comprehensive loss in stockholders’ equity (deficit). Gains and losses resulting from foreign currency transactions are recognized as other (expense) income. The Company did not have any gains or losses resulting from foreign currency transactions during the years ended December 31, 2013, 2012 and 2011.
Stock-Based Compensation
The Company accounts for stock-based compensation awards based on the fair value of the award as of the grant date. The Company recognizes stock-based compensation expense using the accelerated attribution method, net of estimated forfeitures, in which compensation cost for each vesting tranche in an award is recognized ratably from the service inception date to the vesting date for that tranche.
The Company uses the Black-Scholes option pricing model for estimating the fair value of stock options. The use of the option valuation model requires the input of highly subjective assumptions, including the fair value of the Company’s common stock prior to the IPO, the expected life of the option and the expected stock price volatility based on peer companies. Additionally, the recognition of expense requires the estimation of the number of options that will ultimately vest and the number of options that will ultimately be forfeited.
Basic and Diluted Loss per Common Share
The Company uses the two-class method to compute net loss per common share because the Company has issued securities, other than common stock, that contractually entitled the holders to participate in dividends and earnings of the Company. The two-class method requires earnings for the period to be allocated between common stock and participating securities based upon their respective rights to receive distributed and undistributed earnings. Prior to their conversion to common shares, each series of the Company’s redeemable convertible preferred stock was entitled to participate on an as-if-converted basis in distributions, when and if declared by the board of directors, that were made to common stockholders, and as a result these shares were considered participating securities. During 2013, certain shares issued as a result of the early exercise of stock options, which were subject to repurchase by the Company, were entitled to receive non-forfeitable dividends during the vesting period and as a result were also considered participating securities.
Under the two-class method, for periods with net income, basic net income per common share is computed by dividing the net income attributable to common stockholders by the weighted average number of shares of common stock outstanding during the period. Net income attributable to common stockholders is computed by subtracting from net income the portion of current year earnings that the participating securities would have been entitled to receive pursuant to their dividend rights had all of the year’s earnings been distributed. No such adjustment to earnings is made during periods with a net loss, as the holders of the participating securities have no obligation to fund losses. Diluted net loss per common share is computed under the two-class method by using the weighted average number of shares of common stock outstanding, plus, for periods with net income attributable to common stockholders, the potential dilutive effects of stock options and warrants. In addition, the Company analyzes the potential dilutive effect of the outstanding participating securities under the “if-converted” method when calculating diluted earnings per share, in which it is assumed that the outstanding participating securities convert into common stock at the beginning of the period. The Company reports the more dilutive of the approaches (two-class or “if-converted”) as its diluted net income per share during the period. Due to net losses for the years ended December 31, 2013, 2012 and 2011, basic and diluted loss per share were the same, as the effect of potentially dilutive securities would have been anti-dilutive.

Property_and_Equipment

Property and Equipment	12 Months Ended
	Dec. 31, 2013
Property, Plant and Equipment [Abstract]	'
Property and Equipment	'
	Property and Equipment
	Property and equipment consisted of the following as of December 31, 2013 and 2012 (in thousands):
		2013			2012
	Purchased software, including internal-use software	$	6,103		$	3,564
	Computer hardware	12,886			9,346
	Furniture and office equipment	3,012			1,750
	Leasehold improvements	1,507			948
		23,508			15,608
	Less: accumulated depreciation	(14,420		)	(11,293		)
		$	9,088		$	4,315
	Depreciation expense for the years ended December 31, 2013, 2012 and 2011 was $3.1 million, $2.1 million and $1.2 million, respectively.

Goodwill_and_Intangible_Assets

Goodwill and Intangible Assets	12 Months Ended
	Dec. 31, 2013
Goodwill and Intangible Assets Disclosure [Abstract]	'
Goodwill and Intangible Assets	'
	Goodwill and Intangible Assets
	Intangible assets consisted of the following at December 31, 2013 and 2012 (in thousands):
		2013
		Gross Carrying		Accumulated			Net Carrying		Weighted Average
		Amount		Amortization			Amount		Useful Life (in  years)
	Customer relationships	$	4,745	$	(4,225	)	$	520	6.5
	Proprietary software	1,010		(860		)	150		6.8
	Trade name	400		(400		)	—		5
		$	6,155	$	(5,485	)	$	670	6.5
		2012
		Gross Carrying		Accumulated			Net Carrying		Weighted Average
		Amount		Amortization			Amount		Useful Life (in  years)
	Customer relationships	$	4,745	$	(3,779	)	$	966	6.5
	Proprietary software	1,010		(771		)	239		6.8
	Trade name	400		(360		)	40		5
		$	6,155	$	(4,910	)	$	1,245	6.5
	Amortization expense for the years ended December 31, 2013, 2012 and 2011 was $0.6 million, $0.8 million and $0.8 million, respectively. As of December 31, 2013, expected amortization expense over the remaining intangible asset lives is as follows (in thousands):
	2014	$	395
	2015	275
	Total	$	670
	There were no changes to goodwill during the years ended December 31, 2013 and 2012.

Commitments_and_Contingencies

Commitments and Contingencies	12 Months Ended
	Dec. 31, 2013
Commitments and Contingencies Disclosure [Abstract]	'
Commitments and Contingencies	'
	Commitments and Contingencies
	Operating and Capital Lease Commitments
	The Company leases office facilities and certain equipment under non-cancelable operating and capital leases. Future minimum lease payments are as follows (in thousands):
		Operating Leases		Capital Leases
	Year Ending December 31,
	2014	$	1,973	$	1,570
	2015	1,997		1,172
	2016	1,972		450
	2017	1,738		3
	2018	1,827		1
	Thereafter	5,810		—
	Total minimum lease payments	$	15,317	3,196
	Less: imputed interest			(251		)
	Less: current portion			(1,387		)
	Capital lease obligations, net of current portion			$	1,558
	The gross book value of fixed assets under capital leases as of December 31, 2013 and 2012 was approximately $4.2 million and $2.2 million, respectively. The net book value of fixed assets under capital leases as of December 31, 2013 and 2012 was approximately $2.7 million and $1.7 million, respectively. Capital lease obligations are included in other current liabilities and long-term capital leases in the accompanying consolidated balance sheets. The amortization of fixed assets under capital leases is included in depreciation expense in the accompanying consolidated statements of operations.
	Future minimum lease payments due under the non-cancelable operating lease arrangements contain fixed rent increases over the term of the lease. Rent expense on these operating leases is recognized over the term of the lease on a straight-line basis. The excess of rent expense over future minimum lease payments due has been reported in other current liabilities and other long-term liabilities in the accompanying consolidated balance sheets. As of December 31, 2013 and 2012, deferred rent related to these leases totaled $1.2 million and $1.1 million, respectively.
	In January 2011, the lease agreement for the Company’s headquarters, located in Morrisville, North Carolina (the “Morrisville lease”), was amended to extend the lease through September 2021. This amendment included a one-time cash payment to the Company of $0.2 million to be used at the Company’s sole and absolute discretion. This amount was received and recorded as a lease incentive obligation that is amortized against rent expense on a straight-line basis through the life of the lease. As of December 31, 2013, total payments for the remaining term of the Morrisville lease were $9.8 million.
	Total rent expense for the years ended December 31, 2013, 2012 and 2011 was $1.8 million, $1.7 million and $1.1 million, respectively.
	Legal Contingencies
	The Company is a party to a variety of legal proceedings that arise in the normal course of business. While the results of such normal course legal proceedings cannot be predicted with certainty, management believes, based on current knowledge, that the final outcome of any matters will not have a material adverse effect on the Company’s business, financial position, results of operations or cash flows.

Debt_Notes

Debt (Notes)	12 Months Ended
	Dec. 31, 2013
Debt Disclosure [Abstract]	'
Debt	'
	Debt
	Long-term debt consisted of the following at December 31, 2013 and 2012 (in thousands):
		2013		2012
	Revolving line of credit	$	—	$	3,300
	Equipment line of credit	—		70
	Subordinated loan	—		10,000
	Debt discount	—		(2,398		)
	Total debt	—		10,972
	Current portion of long-term debt	—		3,370
	Debt, net of current portion	$	—	$	7,602
	In December 2009, the Company entered into a loan and security agreement (the “Loan and Security Agreement”) with a lender. The Loan and Security Agreement includes a revolving line of aggregate advances (the “Revolving Line of Credit”) totaling $4.3 million. The Revolving Line of Credit had an initial term of 364 days and the Company immediately drew $2.3 million, and subsequently drew an additional $1.0 million during 2011. Interest-only payments are to be made monthly on any outstanding advances during the term at the greater of: the lender’s prime rate plus 0.75%; or 4.75%. In July 2012, the Company amended its Loan and Security Agreement with its lender to increase the borrowing capacity under the Revolving Line of Credit by $1.7 million to $6.0 million, and modify the interest rate of the Revolving Line of Credit to be the lender’s prime rate plus 1.0%.
	The loan is collateralized by all of the Company’s assets, excluding intellectual property. The lender has been granted a negative pledge on all intellectual property of the Company. In conjunction with this transaction, the Company issued to the lender a warrant to purchase shares of Series C redeemable convertible preferred stock (see Note 9, "Warrants"). As of December 31, 2012, all outstanding borrowings under the Revolving Line of Credit were included in the current portion of long-term debt in the accompanying consolidated balance sheet. Each year, the Company has amended its Loan and Security Agreement with its lender to extend the maturity date of the Revolving Line of Credit. In September 2013, the Company amended its Loan and Security Agreement to extend the maturity date to September 17, 2014.
	In June 2010, the Company amended its Loan and Security Agreement with its lender to provide for an equipment line of credit (the “Equipment Line of Credit”), which matures on June 1, 2014. The Equipment Line of Credit provides for the purchase of up to $1.0 million of fixed assets. Principal plus interest is payable monthly over 36 months. Interest is charged at 6.50%. The Equipment Line of Credit is collateralized by the same assets as the Company’s Revolving Line of Credit, in addition to any fixed assets that were purchased utilizing the Equipment Line of Credit.
	As of December 31, 2013, the Company had no amounts outstanding under the Loan and Security Agreement.
	Under the terms of the Loan and Security Agreement, the Company is required to meet and maintain certain monthly and annual financial and nonfinancial covenants. As of December 31, 2013, the Company was in compliance with all such covenants.
	In March 2012, the Company signed a loan and security agreement (the "Subordinated Loan Agreement") with a subordinated lender, which was amended in October 2013. The Subordinated Loan Agreement called for the Company to borrow between $5.0 million and $10.0 million through the end of 2012. Payments on the debt were interest only through March 1, 2015 and principal and interest from March 1, 2015 through the maturity date of February 28, 2017. Interest was payable monthly at an annual rate of 10.5%. In March 2012, the Company borrowed $5.0 million under this Subordinated Loan Agreement and as a condition of the loan, the Company issued to the lender a warrant to purchase shares of Series C redeemable convertible preferred stock (see Note 9, "Warrants"). In December 2012, the Company borrowed the remaining $5.0 million available under the Subordinated Loan Agreement with the subordinated lender. As a result of this additional borrowing, the warrant to purchase Series C redeemable convertible preferred stock became exercisable for additional shares. In November 2013, the Company entered into a payoff agreement with the lender pursuant to which the Company paid all amounts due and owing under the Subordinated Loan Agreement and terminated the Subordinated Loan Agreement. Under the payoff agreement, the Company paid the lender approximately $11.3 million, of which $1.2 million represented a fixed prepayment fee and other extinguishment costs. In connection with this prepayment, the Company recognized a pre-tax loss on extinguishment of debt of $3.1 million during year ended December 31, 2013, representing the difference between the par value and payoff amount of the loan, increased by the write-off of unamortized debt issuance costs and accelerated amortization of the remaining debt discount.

Income_Taxes_Notes

Income Taxes (Notes)	12 Months Ended
	Dec. 31, 2013
Income Tax Disclosure [Abstract]	'
Income Taxes	'
	Income Taxes
	The components of loss before income taxes for the years ended December 31 2013, 2012 and 2011 were as follows (in thousands):
		2013				2012				2011
	Domestic	$	(7,222	)		$	1,821			$	1,061
	Foreign	(13,203		)		(6,824		)		(4,874		)
	Total loss before income taxes	$	(20,425	)		$	(5,003	)		$	(3,813	)
	The provision for income tax expense (benefit) included the following for the years ended December 31, 2013, 2012 and 2011 (in thousands):
		2013				2012				2011
	Current:
	Federal	$	22			$	46			$	4
	State	193				55				(2		)
	Foreign	—				(201		)		—
	Total	215				(100		)		2
	Deferred:
	Federal	(26		)		28				47
	State	14				2				2
	Total	(12		)		30				49
	Total tax expense (benefit)	$	203			$	(70	)		$	51
	Deferred income taxes reflect the net tax effect of temporary differences between the carrying amount of assets and liabilities for financial reporting purposes and the amounts used for income tax purposes. The components of the Company’s net deferred tax assets (liabilities) as of December 31, 2013, 2012 and 2011 were as follows (in thousands):
		2013				2012				2011
	Current:
	Deferred tax assets:
	Other assets	$	832			$	585			$	576
	Valuation allowance	(726		)		(539		)		(529		)
	Total deferred tax assets	106				46				47
	Deferred tax liabilities:
	Other liabilities	71				11				3
	Net deferred tax asset, current	$	35			$	35			$	44
	Noncurrent:
	Deferred tax assets:
	Domestic tax loss carryforwards	$	18,898			$	17,288			$	18,067
	Foreign tax loss carryforwards	7,673				5,526				4,202
	Tax credits	78				57				11
	Other assets	866				900				1,149
	Valuation allowance	(26,206		)		(22,040		)		(21,615		)
	Total deferred tax assets	1,309				1,731				1,814
	Deferred tax liabilities:
	Fixed assets	1,149				1,214				518
	Other liabilities	383				752				1,510
	Total deferred tax liabilities	1,532				1,966				2,028
	Net deferred tax liability, noncurrent	$	(223	)		$	(235	)		$	(214	)
	At December 31, 2013, 2012 and 2011, the Company had federal gross operating loss carryforwards of $62.5 million, $46.3 million and $48.8 million, respectively, that expire beginning in 2022. At December 31, 2013, 2012 and 2011, the Company had state net economic loss carryforwards of $55.2 million, $45.1 million and $44.8 million, respectively, that expire beginning in 2018. The Company’s federal and state net operating losses include $12.0 million of excess tax benefits related to deductions from the exercise of nonqualified stock options. The tax benefit of these deductions has not been recognized in deferred tax assets. If utilized, the benefits from these deductions will be recorded as adjustments to taxes payable and additional paid-in-capital. The utilization of the net operating loss and tax credit carryforwards may be subject to limitation under the rules regarding a change in stock ownership as determined by the Internal Revenue Code and state and foreign tax laws. The Company is in the process of assessing any limitations, particularly related to net operating loss carryforwards from its acquired entities. At December 31, 2013, 2012 and 2011, the Company also had foreign net operating loss (“NOL”) carryforwards for use against future tax in those jurisdictions of $25.1 million, $16.4 million and $12.4 million, respectively, that expire beginning in 2019.
	A valuation allowance has been recognized to offset the deferred tax assets related to all NOL carryforwards. The total increase in valuation allowance of $4.4 million during the year ended December 31, 2013 was allocable to current operating activities. Two notable items related to the valuation allowance analysis are the deferred tax liability associated with an indefinite-lived intangible asset and the U.S. federal alternative minimum tax credit carryforward. Specifically, the deferred tax liability associated with the tax deductible amortization on the indefinite-lived intangible asset cannot be netted against other deferred tax assets in arriving at the valuation allowance to be recorded. In addition, the deferred tax asset related to the alternative minimum tax credit carryforward has no expiration date under federal tax law. Since both the deferred tax liability and the deferred tax asset have indefinite lives, they offset each other to arrive at the net deferred tax liability.
	The utilization of the loss carryforwards to reduce future income taxes will depend on the Company’s ability to generate sufficient taxable income prior to the expiration of the NOL carryforwards. In addition, the maximum annual use of NOL carryforwards is limited in certain situations after changes in stock ownership occur. There were no recognized tax benefits related to NOL carryforwards for the year ended December 31, 2013. Income tax expense (benefit) for the years ended December 31 2013, 2012 and 2011 was $0.2 million, $(0.1) million and $0.1 million, respectively.
	Undistributed earnings of the Company’s foreign subsidiaries are considered permanently reinvested and, accordingly, no provision for U.S. federal or state income taxes has been provided thereon. The cumulative amount of undistributed earnings of the Company’s non-U.S. subsidiaries was approximately $0.8 million for each of the years ended December 31, 2013, 2012 and 2011. The determination of the deferred tax liability, which requires complex analysis of international tax situations related to repatriation, is not practicable at this time. The Company is presently investing in international operations located in Europe, Asia, Australia and South America. The Company is funding the working capital needs of its foreign operations through its U.S. operations. In the future, the Company will utilize its foreign undistributed earnings, as well as continued funding from its U.S. operations, to support its continued foreign investment.
	A reconciliation of the difference between the effective income tax rate and the statutory federal income tax rate for the years ended December 31, 2013, 2012 and 2011 is as follows:
		2013			2012			2011
	U.S. statutory federal rate	34	%		34	%		34	%
	Increase (decrease) resulting from:
	State taxes, net of federal benefit	1.6			(0.8	)		0.5
	Nondeductible expenses	(5.2	)		(9.2	)		(6.2	)
	Effect of foreign tax rate differential	(8.0	)		(13.3	)		(10.8	)
	NOL adjustment	—			—			(35.1	)
	Change in valuation allowance	(22.4	)		(6.6	)		15.8
	Other	(1.0	)		(2.7	)		0.6
	Effective tax rate	(1.0	)%		1.4	%		(1.2	)%
	The nondeductible expenses during the year ended December 31, 2013 primarily related to stock compensation expense associated with incentive stock options and nondeductible interest expense.
	Effective January 1, 2009, the Company adopted the provisions of the Financial Accounting Standards Board ("FASB") guidance on accounting for uncertainty in income taxes. These provisions provide a comprehensive model for the recognition, measurement and disclosure in financial statements of uncertain income tax positions that a company has taken or expects to take on a tax return.
	As a result of implementing these provisions, the Company did not identify any material tax positions that would be required for inclusion in the financial statements under this accounting guidance. As of December 31, 2013 and 2012, the Company had no accrued interest or penalties related to the tax contingencies. The Company’s policy for recording interest and penalties is to record them as a component of provision for income taxes.
	The Company has analyzed its filing positions in all significant federal, state and foreign jurisdictions where it is required to file income tax returns, as well as open tax years in these jurisdictions. With few exceptions, the Company is no longer subject to U.S. federal and state and local tax examinations by tax authorities for years prior to 2010, although carryforward attributes that were generated prior to 2010 may still be adjusted upon examination by the Internal Revenue Service if they either have been or will be used in a future period. The Company is no longer subject to examination in foreign tax jurisdictions for tax periods 2008 and prior. No income tax returns are currently under examination by taxing authorities.

Stockholders_Equity_Deficit_an

Stockholders' Equity (Deficit) and Redeemable Convertible Preferred Stock (Notes)	12 Months Ended
	Dec. 31, 2013
Equity [Abstract]	'
Stockholders' Equity (Deficit) and Redeemable Convertible Preferred Stock	'
	Stockholders’ Equity (Deficit) and Redeemable Convertible Preferred Stock
	The following table summarizes the issuances of redeemable convertible preferred stock prior to the IPO:
	Name		Price per			Number of		Conversion
			Share			Shares		Price per Share
	Series A		$	0.2		93,966,024		$	3.2
	Series B		$	0.44		40,641,227		$	7.04
	Series B-1		$	0.53		5,660,378		$	8.48
	Series C		$	0.69		74,156,709		$	10.96
	Series A, Series B, Series B-1 and Series C redeemable convertible preferred stock are collectively referred to as the “Preferred Stock” and individually as the “Series A,” “Series B,” “Series B-1” and “Series C.” Each of the prices per share above is referred to as the Original Issue Price, and excludes the cost of issuance.
	The following table presents a summary of activity for the Preferred Stock issued and outstanding for the years ended December 31, 2013, 2012 and 2011 (in thousands):
		Redeemable Convertible Preferred Stock
		Series A			Series B			Series B-1			Series C			Total
														Amount
	Balance, January 1, 2011	18,805			17,989			2,998			50,571			90,363
	Accretion of issuance costs on Preferred Stock	11			8			1			30			50
	Balance, December 31, 2011	18,816			17,997			2,999			50,601			90,413
	Cashless exercise of warrants	67			—			—			—			67
	Accretion of issuance costs on Preferred Stock	4			3			1			7			15
	Balance, December 31, 2012	$	18,887		$	18,000		$	3,000		$	50,608		$	90,495
	Cashless exercise of warrants	166			—			—			489			655
	Conversion of Preferred Stock into common stock	(19,053		)	(18,000		)	(3,000		)	(51,097		)	(91,150		)
	Balance, December 31, 2013	$	—		$	—		$	—		$	—		$	—
	Upon the closing of the IPO, certain Series C warrants that would otherwise have terminated were automatically net exercised into 206,038 shares of redeemable convertible preferred stock. All then-outstanding shares of the Company’s redeemable convertible preferred stock were automatically converted into 13,401,499 shares of common stock. The remaining warrants to purchase redeemable convertible preferred stock outstanding as of the closing of the IPO automatically converted into warrants to purchase an aggregate of 216,491 shares of common stock.
	In addition, upon the closing of the IPO, the Company’s certificate of incorporation was amended and restated to authorize 5,000,000 shares of undesignated preferred stock and 100,000,000 shares of common stock. Both the common stock and undesignated preferred stock have a par value of $0.001 per share.

Warrants

Warrants	12 Months Ended
	Dec. 31, 2013
Other Liabilities Disclosure [Abstract]	'
Warrants	'
	Warrants
	Preferred Stock Warrants
	In conjunction with previous long-term debt borrowings, the Company issued warrants to purchase shares of Series A and Series C. As of December 31, 2012, the holders of the Series A and Series C warrants were entitled to purchase a total of 175,000 shares of Series A and 4,586,121 shares of Series C. The warrants could be exercised in whole or in part at any time and included a cashless exercise feature, allowing the holder to receive fewer shares of Series A or Series C in exchange for the warrant, rather than paying cash to exercise. The warrants were classified as a liability as of December 31, 2012 in the accompanying consolidated balance sheet.
	The fair values of the Series A warrants and Series C warrants were estimated to be $0.1 million and $3.1 million, respectively, at December 31, 2012. The inputs into the fair value model for the warrants, which are discussed in Note 2, "Significant Accounting Policies - Fair Value of Financial Instruments," were considered Level 3 inputs under ASC 820, "Fair Value Measurements and Disclosures." Prior to the closing of the IPO, all changes in the fair value of the warrants were recorded in interest expense in the accompanying consolidated statements of operations. The Company recorded interest expense of $1.1 million, $5,000 and $0.3 million for the years ended December 31, 2013, 2012 and 2011, respectively, related to the fair value adjustment of the warrants.
	Certain Series C warrants that would have otherwise terminated upon the closing of the IPO were automatically net exercised for an aggregate of 206,038 shares of Series C, which were then automatically converted into 12,874 shares of common stock upon the closing of the IPO. The remaining warrants to purchase redeemable convertible preferred stock converted into warrants to purchase an aggregate of 216,491 shares of common stock, and the related preferred stock warrant liability at its then fair value of $3.6 million was reclassified to additional paid-in capital upon the closing of the IPO.
	In May 2013, a holder of Series A and Series C warrants exercised those warrants on a cashless basis and received 144,631 shares of Series A and 70,320 shares of Series C, respectively, in exchange for the warrants. These shares of Series A and Series C converted into an aggregate of 13,433 shares of common stock upon the closing of the IPO.
	Common Stock Warrants
	In 2007 and 2008, in conjunction with the Series C funding, the Company also issued warrants to purchase 1,616,113 shares of common stock, of which 958,019 and 658,094 have exercise prices per share of $16.00 and $10.96, respectively. The 2007 and 2008 warrants expire in 2014 and 2015, respectively. The warrants may be exercised in whole or in part at any time and include a cashless exercise feature, which allows the holder to receive fewer shares of common stock in exchange for the warrant rather than paying cash to exercise.
	In June 2013, the holder of a warrant to purchase common stock executed a cashless exercise and received 194,885 shares of common stock in exchange for the warrant.
	In September 2013, the holder of a warrant to purchase common stock executed a cashless exercise and received 6,511 shares of common stock in exchange for the warrant.
	In November 2013, in connection with our registered public offering, the holders of certain warrants to purchase common stock executed cashless exercises and received 317,011 shares of common stock in exchange for the warrants. In addition, certain holders of warrants to purchase common stock executed exercises and received 55,316 shares of common stock in exchange for the warrants.
	In December 2013, the holder of a warrant to purchase common stock executed an exercise and received 88,639 shares of common stock in exchange for the warrant.

Equity_Incentive_Plans_and_Sto

Equity Incentive Plans and Stock-Based Compensation	12 Months Ended
	Dec. 31, 2013
Disclosure of Compensation Related Costs, Share-based Payments [Abstract]	'
Equity Incentive Plans and Stock-Based Compensation	'
	Equity Incentive Plans and Stock-Based Compensation
	In May 2013, the Company’s board of directors adopted, and the Company’s stockholders approved, the 2013 Equity Incentive Plan (the “2013 Plan”), pursuant to which the Company initially reserved 1,250,000 shares of its common stock for issuance to its employees, directors and non-employee third parties. The 2013 Plan provides for the grant of incentive stock options to employees, and for the grant of nonqualified stock options, restricted stock awards, restricted stock unit awards, stock appreciation rights, performance stock awards and other forms of stock compensation to the Company’s employees, directors, and non-employee third parties. The number of shares of common stock reserved for issuance under the 2013 Plan will automatically increase on January 1 each year, for a period of ten years, from January 1, 2014 through January 1, 2023, by 5% of the total number of shares of the Company’s common stock outstanding on December 31 of the preceding calendar year, or a lesser number of shares as may be determined by the Company’s board of directors. Accordingly, on January 1, 2014 the number of shares reserved for issuance under the 2013 Plan increased by 1,182,194 shares. As a result of the adoption of the 2013 Plan, no further grants may be made under the 2001 Stock Plan described below (the “2001 Plan”). As of December 31, 2013, 1,104,951 shares remained available for future grant under the 2013 Plan.
	The 2001 Plan provided for the grant of incentive stock options to employees, and for the grant of nonqualified stock options to employees, directors and non-employee third parties. Stock options were granted at exercise prices not less than the estimated fair market value of the Company’s common stock at the date of grant. Stock options generally expire ten years from the date of grant. Certain options are eligible for exercise prior to vesting. Shares issued as a result of early exercise are subject to repurchase by the Company upon termination of employment or services, at the lesser of the price paid or the fair value of the shares on the repurchase date. No such shares were outstanding at December 31, 2013 or 2012.
	Stock-based compensation expense related to stock options is included in the following line items in the accompanying consolidated statements of operations for the years ended December 31, 2013, 2012 and 2011 (in thousands):
		2013				2012			2011
	Cost of revenue	$	204			$	64		$	15
	Sales and marketing	607				224			16
	Research and development	348				105			58
	General and administrative	940				245			111
		$	2,099			$	638		$	200
	The Company values stock options using the Black-Scholes option-pricing model, which requires the input of subjective assumptions, including the risk-free interest rate, expected life, expected stock price volatility and dividend yield. The risk-free interest rate assumption is based upon observed interest rates for constant maturity U.S. Treasury securities consistent with the expected term of the Company’s employee stock options. The expected life represents the period of time the stock options are expected to be outstanding and is based on the “simplified method.” Under the “simplified method,” the expected life of an option is presumed to be the mid-point between the vesting date and the end of the contractual term. The Company used the “simplified method” due to the lack of sufficient historical exercise data to provide a reasonable basis upon which to otherwise estimate the expected life of the stock options. Expected volatility is based on historical volatilities for publicly traded stock of comparable companies over the estimated expected life of the stock options. The Company assumed no dividend yield because dividends are not expected to be paid in the near future, which is consistent with the Company’s history of not paying dividends.
	The following table summarizes the assumptions used for estimating the fair value of stock options granted for the years ended December 31, 2013, 2012 and 2011:
		2013		2012		2011
	Risk-free interest rate	0.3% - 1.7%		0.1% - 0.9%		0.4% - 2.0%
	Expected term (years)	5.00 - 6.25		4.00 - 6.25		6.25
	Expected volatility	43% - 59%		49% - 60%		28% - 56%
	Dividend yield	0%		0%		0%
	The following is a summary of the option activity for the year ended December 31, 2013:
		Number of			Weighted Average			Weighted		Aggregate
		Options			Exercise Price			Average		Intrinsic Value
								Remaining
								Contractual
								Term
								(in years)		(in thousands)
	Outstanding balance at December 31, 2012	2,202,712			$	3.84
	Granted	722,625			12.74
	Exercised	(727,318	)		3.36
	Forfeited	(104,042	)		8.3
	Expired	(25,336	)		2.67
	Outstanding balance at December 31, 2013	2,068,641			$	6.95		7.8		$	71,914
	Exercisable at December 31, 2013	938,151			$	3.3		6.6		$	36,039
	Vested and expected to vest at December 31, 2013	1,813,530			$	6.62		7.68		$	63,636
	The weighted average grant date fair value for the Company's stock options granted during the years ended December 31, 2013, 2012 and 2011 was $5.29, $2.88 and $0.80 per share, respectively. The total fair value of stock options vested during the years ended December 31, 2013, 2012 and 2011 was $0.9 million, $0.4 million and $0.2 million, respectively. The total compensation cost related to nonvested awards not yet recognized as of December 31, 2013 was $2.2 million and will be recognized over a weighted average period of approximately 1.9 years. The aggregate intrinsic value of stock options exercised during the years ended December 31, 2013, 2012, and 2011 was $17.6 million, $0.7 million and $0.1 million, respectively.

Net_Loss_Per_Share

Net Loss Per Share	12 Months Ended
	Dec. 31, 2013
Earnings Per Share [Abstract]	'
Net Loss Per Share	'
	Net Loss Per Share
	Diluted loss per share is the same as basic loss per share for all periods presented because the effects of potentially dilutive items were anti-dilutive given the Company’s net loss. The following securities have been excluded from the calculation of weighted average common shares outstanding because the effect is anti-dilutive for the years ended December 31, 2013, 2012 and 2011:
		2013	2012	2011
	Redeemable convertible preferred stock:
	Series A	—	5,863,825	5,857,864
	Series B	—	2,540,066	2,540,066
	Series B-1	—	353,767	353,767
	Series C	—	4,617,513	4,617,513
	Warrants to purchase common stock	986,784	1,616,113	1,616,113
	Warrants to purchase Series A redeemable convertible preferred stock	—	10,937	21,484
	Warrants to purchase Series C redeemable convertible preferred stock	—	286,625	89,750
	Stock options	2,068,641	2,202,712	1,936,191

Segment_and_Geographic_Informa

Segment and Geographic Information	12 Months Ended
	Dec. 31, 2013
Segment Reporting [Abstract]	'
Segment and Geographic Information	'
	Segment and Geographic Information
	Operating segments are defined as components of an enterprise for which discrete financial information is available that is evaluated regularly by the chief operating decision maker (“CODM”) for purposes of allocating resources and evaluating financial performance. The Company’s CODM reviews financial information presented on a consolidated basis for purposes of allocating resources and evaluating financial performance. As such, the Company’s operations constitute a single operating segment and one reportable segment.
	Substantially all assets were held in the United States during the years ended December 31, 2013 and 2012. The following table summarizes revenue by geography for the years ended December 31, 2013, 2012 and 2011 (in thousands):
		2013		2012		2011
	Revenue:
	Domestic	$	53,832	$	42,140	$	34,805
	International	14,172		11,447		8,765
	Total	$	68,004	$	53,587	$	43,570

Retirement_Plan_Notes

Retirement Plan (Notes)	12 Months Ended
	Dec. 31, 2013
Compensation and Retirement Disclosure [Abstract]	'
Retirement Plan	'
	Retirement Plan
	The Company established the ChannelAdvisor Corporation 401(k) Profit Sharing Plan (the “Retirement Plan”), a contributory profit sharing plan, to cover all employees who qualify under the terms of the plan. Eligible employees may elect to contribute to the Retirement Plan up to 100% of their compensation, limited by the IRS-imposed maximum. Prior to April 1, 2011, the Company did not match employee contributions to the Retirement Plan. Effective April 1, 2011, the Company began matching 50% of employee contributions up to 3% of base salary. Employer contributions were $0.3 million, $0.3 million and $0.2 million for the years ended December 31, 2013, 2012 and 2011, respectively.

Selected_Quarterly_Information

Selected Quarterly Information (unaudited) (Notes)	12 Months Ended
	Dec. 31, 2013
Quarterly Financial Information Disclosure [Abstract]	'
Selected Quarterly Information (unaudited)	'
	Selected Quarterly Information (unaudited)
		Three Months Ended
		March 31,			June 30,			September 30,			December 31,
		2013			2013			2013			2013
		(in thousands, except per share amounts)
	Revenue	$	14,922		$	15,976		$	16,620		$	20,486
	Gross profit	10,975			11,507			12,065			15,369
	Loss from operations	(2,137		)	(3,496		)	(3,741		)	(4,991		)
	Net loss	(2,730		)	(4,997		)	(4,292		)	(8,609		)
	Net loss per share:
	Basic and diluted	(2.10		)	(0.56		)	(0.20		)	(0.38		)
		Three Months Ended
		March 31,			June 30,			September 30,			December 31,
		2012			2012			2012			2012
		(in thousands, except per share amounts)
	Revenue	$	12,166		$	12,408		$	13,020		$	15,993
	Gross profit	8,920			8,778			9,189			11,951
	(Loss) income from operations	(809		)	(2,347		)	(1,517		)	824
	Net (loss) income	(851		)	(2,750		)	(1,958		)	626
	Net (loss) income per share:
	Basic and diluted	(0.74		)	(2.39		)	(1.68		)	0.04

Subsequent_Events

Subsequent Events	12 Months Ended
	Dec. 31, 2013
Subsequent Events [Abstract]	'
Subsequent Events	'
	Subsequent Events
	In January 2014, the holders of certain warrants to purchase common stock executed cashless exercises and received 664,058 shares of common stock in exchange for the warrants.
	Effective as of January 3, 2014, the Company signed ten-year lease agreements with five-year break options for its office in London, England. Total collective future minimum lease payments for the five- and ten-year lease terms are approximately £4.4 million and £9.4 million ($7.3 million and $15.5 million, based on the exchange rate as of December 31, 2013), respectively.

Significant_Accounting_Policie1

Significant Accounting Policies (Policies)	12 Months Ended
	Dec. 31, 2013
Accounting Policies [Abstract]	'
Principles of Consolidation	'
	Principles of Consolidation
	The accompanying consolidated financial statements include the accounts of the Company and its wholly-owned subsidiaries. All intercompany accounts and transactions have been eliminated in consolidation.
Reverse Stock Split	'
	Reverse Stock Split
	On May 9, 2013, the Company’s amended and restated certificate of incorporation was amended to effect a 1-for-16 reverse stock split of its outstanding common stock. The reverse stock split did not cause an adjustment to the par value or the authorized shares of the common stock. As a result of the reverse stock split, the share amounts under the Company’s employee incentive plan and common stock warrants were automatically adjusted. The accompanying consolidated financial statements and notes to the consolidated financial statements give retroactive effect to the reverse stock split for all periods presented.
Public Offerings	'
	Public Offerings
	On May 29, 2013, the Company closed the initial public offering ("IPO") of its common stock pursuant to a registration statement on Form S-1 that was declared effective on May 22, 2013. In the IPO, the Company sold an aggregate of 6,612,500 shares of common stock, including the full exercise of the underwriters’ option to purchase additional shares, at a public offering price of $14.00 per share. Net proceeds were approximately $82.0 million, after deducting underwriting discounts and commissions of $6.5 million and offering expenses of $4.1 million. Costs directly associated with the IPO were capitalized and recorded as deferred offering costs prior to the closing of the IPO. These costs were recorded as a reduction of the IPO proceeds received in calculating the amount to be recorded in additional paid-in capital.
	Upon the closing of the IPO, certain Series C warrants that would otherwise have expired were automatically net exercised into 206,038 shares of redeemable convertible preferred stock. All then-outstanding shares of the Company’s redeemable convertible preferred stock were automatically converted into 13,401,499 shares of common stock. The remaining warrants to purchase redeemable convertible preferred stock outstanding as of the closing of the IPO automatically converted into warrants to purchase an aggregate of 216,491 shares of common stock, and the preferred stock warrant liability was reclassified to additional paid-in capital as of May 29, 2013.
	In addition, upon the closing of the IPO, the Company’s certificate of incorporation was amended and restated to authorize 5,000,000 shares of undesignated preferred stock and 100,000,000 shares of common stock.
	On November 12, 2013, the Company closed a registered public offering of its common stock pursuant to a registration statement on Form S-1 that was declared effective on November 5, 2013. In the registered public offering, the Company sold and issued 1,000,000 shares of common stock at a public offering price of $34.00 per share. Net proceeds were approximately $31.9 million, after deducting underwriting discounts and commissions of $1.6 million and offering expenses of $0.5 million.
Recent Accounting Pronouncements	'
	Recently Adopted Accounting Pronouncements
	The Company has reviewed accounting pronouncements that were issued as of December 31, 2013 and does not believe that these pronouncements will have a material impact on its financial position or results of operations.
Use of Estimates	'
	Use of Estimates
	The preparation of financial statements in conformity with United States generally accepted accounting principles (“U.S. GAAP”) requires management to make estimates and assumptions that affect the amounts reported in the consolidated financial statements and accompanying notes. Actual results could differ from those estimates.
	On an ongoing basis, the Company evaluates its estimates, including those related to the accounts receivable allowance, the useful lives of long-lived assets and other intangible assets, assumptions used for purposes of determining stock-based compensation, income taxes, and the fair value of the Series A and Series C warrants and the Company’s common stock prior to the closing of the IPO, among others. The Company bases its estimates on historical experience and on various other assumptions that it believes to be reasonable, the results of which form the basis for making judgments about the carrying value of assets and liabilities.
Cash and Cash Equivalents	'
	Cash and Cash Equivalents
	The Company considers all highly liquid investments maturing within ninety days or less at the time of purchase to be cash equivalents. Cash and cash equivalents are comprised of cash and money market funds. Due to the short-term nature and liquidity of these financial instruments, the carrying value of these assets approximates fair value.
Restricted Cash	'
	Restricted Cash
	Restricted cash represents cash that is not readily available for general purpose cash needs. Restricted cash is classified as a long-term asset based on the timing and nature of when and how the cash is expected to be used or when the restrictions are expected to lapse.
	As of December 31, 2013 and 2012, the Company had restricted cash of $0.7 million related to its operations in the United States. Of this amount, $0.6 million has been used as collateral for potential chargebacks resulting from the Company’s processing of customers’ credit cards as of December 31, 2013 and 2012. The remaining restricted cash at December 31, 2013 and 2012 relates to cash set aside as a requirement for leasing the Company’s operating sites or for miscellaneous banking activity as required by the Company’s banks.
Revenue Recognition and Deferred Revenue	'
	Revenue Recognition and Deferred Revenue
	The majority of the Company’s revenue is derived from subscription fees paid by customers for access to and usage of the Company’s cloud-based SaaS platform for a specified period of time, which is typically one year. A portion of the subscription fee is typically fixed and is based on a specified minimum amount of gross merchandise value (“GMV”) that a customer expects to process through the Company’s platform over the contract term. The remaining portion of the subscription fee is variable and is based on a specified percentage of GMV processed through the Company’s platform in excess of the customer’s specified minimum GMV amount. In addition, other sources of revenue consist primarily of implementation fees, which may include fees for providing launch assistance and training. The Company recognizes revenue when there is persuasive evidence of an arrangement, the service has been provided to the customer, the collection of the fee is reasonably assured and the amount of the fee to be paid by the customer is fixed or determinable. The Company’s contractual arrangements include performance, termination and cancellation provisions, but do not provide for refunds. Customers do not have the contractual right to take possession of the Company’s software at any time.
	The Company’s arrangements generally contain multiple elements comprised of subscription and implementation services. The Company evaluates each element in an arrangement to determine whether it represents a separate unit of accounting. An element constitutes a separate unit of accounting when the delivered item has standalone value and delivery of the undelivered element is probable and within the Company’s control. The Company’s implementation services are not sold separately from the subscription and there is no alternative use for them. As such, the Company has determined the implementation services do not have standalone value. Accordingly, subscription and implementation services are combined and recognized as a single unit of accounting.
	The Company generally recognizes the fixed portion of subscription fees and implementation fees ratably over the contract term. Recognition begins when the customer has access to the Company’s platform and transactions can be processed, provided all other revenue recognition criteria have been met. Some customers elect a managed-service solution and contract with the Company to manage some or all aspects of the Company’s SaaS solutions on the customer’s behalf for a specified period of time, which is typically one year. Under these managed-service arrangements, customer transactions cannot be processed through the Company’s platform until the completion of the implementation services. As such, revenue is contingent upon the Company’s completion of the implementation services and recognition commences when transactions can be processed on the Company’s platform, provided all other revenue recognition criteria have been satisfied. At that time, the Company recognizes a pro-rata portion of the fees earned since the inception of the arrangement. The balance of the fees is recognized ratably over the remaining contract term.
	The Company recognizes the variable portion of subscription fee revenue in the period in which the related GMV is processed, provided all other revenue recognition criteria have been met.
	Sales taxes collected from customers and remitted to government authorities are excluded from revenue.
	Deferred revenue represents the unearned portion of fixed subscription fees and implementation fees. Deferred amounts will generally be recognized within one year. Those amounts that are expected to be recognized in greater than one year are recorded in other long-term liabilities in the accompanying consolidated balance sheets.
Sales Commissions	'
	Sales Commissions
	Sales commissions are expensed when the related subscription agreement is executed by the customer.
Cost of Revenue	'
	Cost of Revenue
	Cost of revenue primarily consists of personnel and related costs, including salaries, bonuses, payroll taxes and stock compensation, co-location facility costs for the Company’s data centers, depreciation expense for computer equipment directly associated with generating revenue, credit card transaction fees and infrastructure maintenance costs. In addition, the Company allocates a portion of overhead, such as rent, additional depreciation and amortization and employee benefits costs, to cost of revenue based on headcount.
Fair Value of Financial Instruments	'
	Fair Value of Financial Instruments
	The carrying amounts of certain of the Company’s financial instruments, including cash and cash equivalents, accounts receivable, accounts payable and accrued expenses, approximate their respective fair values due to their short-term nature. Prior to the closing of the IPO on May 29, 2013, at which time certain Series C warrants were automatically net exercised and the remaining warrants converted into common stock warrants, the Company's Series A and Series C warrants were recorded at fair value.
	The Company uses a three-tier fair value hierarchy to classify and disclose all assets and liabilities measured at fair value on a recurring basis, as well as assets and liabilities measured at fair value on a non-recurring basis, in periods subsequent to their initial measurement. The hierarchy requires the Company to use observable inputs when available, and to minimize the use of unobservable inputs when determining fair value. The three tiers are defined as follows:
	•Level 1. Observable inputs based on unadjusted quoted prices in active markets for identical assets or liabilities;
	•Level 2. Inputs, other than quoted prices in active markets, that are observable either directly or indirectly; and
	•Level 3. Unobservable inputs for which there is little or no market data, which require the Company to develop its own assumptions.
	Assets and Liabilities Measured at Fair Value on a Recurring Basis
	The Company evaluates its financial assets and liabilities subject to fair value measurements on a recurring basis to determine the appropriate level in which to classify them for each reporting period. This determination requires significant judgments to be made. The following table summarizes the conclusions reached as of December 31, 2012 (in thousands):
		Balance as of		Level 1		Level 2		Level 3
		December 31,
		2012
	Liabilities:
	Series A warrants(1)	$	88	$	—	$	—	$	88
	Series C warrants(1)	3,147		—		—		3,147
		$	3,235	$	—	$	—	$	3,235
	_______________________
	(1) In order to determine the fair value of the redeemable convertible preferred stock warrants, the Company used a hybrid of the probability-weighted expected return method (“PWERM”) and the option pricing model ("OPM"), collectively referred to as the “Hybrid Method,” for the year ended December 31, 2012. The Hybrid Method is a PWERM model in which one of the valuation scenarios is modeled using an OPM.
	Significant inputs for the OPM included an estimate of the fair value of the Series A and Series C redeemable convertible preferred stock, the remaining contractual life of the warrants, an estimate of the timing of a liquidity event, a risk-free rate of interest and an estimate of the Company’s stock volatility using the volatilities of guideline peer companies. Significant inputs for the PWERM included an estimate of the Company’s equity value, a weighted average cost of capital and an estimated probability and timing for each valuation scenario.
Concentration of Credit Risk	'
	Concentration of Credit Risk
	Financial instruments that subject the Company to significant concentrations of credit risk consist primarily of cash and cash equivalents and accounts receivable. All of the Company’s cash and cash equivalents are held at financial institutions that management believes to be of high credit quality. The Company’s cash and cash equivalent accounts exceed federally insured limits. The Company has not experienced any losses on cash and cash equivalents to date. To manage accounts receivable risk, the Company maintains an allowance for doubtful accounts.
	The Company did not have any customers that individually comprised a significant concentration of its accounts receivable as of December 31, 2013 and 2012, or a significant concentration of its revenue for the years ended December 31, 2013, 2012 and 2011.
Accounts Receivable and Allowance for Doubtful Accounts	'
	Accounts Receivable and Allowance for Doubtful Accounts
	The Company extends credit to customers without requiring collateral. Accounts receivable are stated at realizable value, net of an allowance for doubtful accounts. The Company utilizes the allowance method to provide for doubtful accounts based on management’s evaluation of the collectability of amounts due. The Company’s estimate is based on historical collection experience and a review of the current status of accounts receivable. Historically, actual write-offs for uncollectible accounts have not significantly differed from the Company’s estimates.
Other Receivables	'
	Other Receivables
	Under certain customer arrangements, the Company collects and remits monthly activity-based fees incurred on specific channels on the customers’ behalf. The Company records the amounts due from customers as a result of these arrangements as other receivables.
	Other receivables of $1.7 million and $1.5 million are included in prepaid expenses and other current assets on the consolidated balance sheets as of December 31, 2013 and 2012, respectively.
Deferred Offering Costs	'
	Deferred Offering Costs
	Deferred offering costs of $2.3 million are included in other assets on the consolidated balance sheet as of December 31, 2012. Upon the completion of the IPO, these amounts were offset against the proceeds of the offering and included in stockholders’ equity (deficit). There were no amounts capitalized as of December 31, 2013.
Property and Equipment	'
	Property and Equipment
	Property and equipment are recorded at cost. Expenditures for major additions and improvements are capitalized. Depreciation and amortization is provided over the estimated useful lives of the related assets using the straight-line method.
	The estimated useful lives for significant property and equipment categories are generally as follows:
	Purchased software, including internal-use software	3 years
	Computer hardware	3 years
	Furniture and office equipment	3 to 5 years
	Leasehold improvements	Lesser of remaining lease term or useful life
	Repairs and maintenance costs are expensed as incurred.
Identifiable Intangible Assets	'
	Identifiable Intangible Assets
	The Company acquired intangible assets in connection with its business acquisitions. These assets were recorded at their estimated fair values at the acquisition date and are being amortized over their respective estimated useful lives using the straight-line method. The estimated useful lives used in computing amortization are as follows:
	Customer relationships	5 to 8 years
	Proprietary software	8 years
	Trade name	5 years
Impairment of Long-Lived Assets	'
	Impairment of Long-Lived Assets
	The Company reviews long-lived assets and definite-lived intangible assets for impairment whenever events or changes in circumstances indicate the carrying amount of an asset may not be recoverable. Recoverability of the long-lived asset is measured by a comparison of the carrying amount of the asset or asset group to future undiscounted net cash flows expected to be generated by the asset or asset group. If such assets are not recoverable, the impairment to be recognized, if any, is measured by the amount by which the carrying amount of the assets exceeds the estimated fair value of the assets or asset group. Assets held for sale are reported at the lower of the carrying amount or fair value, less costs to sell. As of December 31, 2013 and 2012, management does not believe any long-lived assets are impaired and has not identified any assets as being held for sale.
Goodwill	'
	Goodwill
	Goodwill represents the excess of the aggregate of the fair value of consideration transferred in a business combination over the fair value of assets acquired, net of liabilities assumed. Goodwill is not amortized, but is subject to an annual impairment test. The Company tests goodwill for impairment annually on December 31, or more frequently if events or changes in business circumstances indicate the asset might be impaired.
	The Company has determined that it has a single, entity-wide reporting unit. Prior to the IPO, the Company determined the fair value of its reporting unit primarily using a discounted cash flow analysis, which required significant assumptions and estimates about future operations. Significant judgments inherent in this analysis included the determination of an appropriate discount rate, estimated terminal value and the amount and timing of expected future cash flows. Subsequent to the IPO, the Company uses market capitalization to determine the fair value of its entity-wide reporting unit.
	During the year ended December 31, 2012, the Company adopted ASU 2011-08, “Intangibles — Goodwill and Other (Topic 350): Testing Goodwill for Impairment,” which gives entities testing goodwill for impairment the option of performing a qualitative assessment to determine whether it is more likely than not that the fair value of a reporting unit is less than its carrying amount. During this assessment, the Company first assesses qualitative factors to determine whether it is more likely than not that the fair value of its reporting unit is less than its carrying amount. Qualitative factors considered include, but are not limited to, macroeconomic conditions, industry and market conditions, company-specific events, changes in circumstances and after-tax cash flows. As of December 31, 2013, the Company determined that its reporting unit did not have a carrying value that was more likely than not to exceed its fair value.
	If the qualitative factors indicate that it is more likely than not that the fair value of the reporting unit is less than its carrying amount, the Company would test goodwill for impairment at the reporting unit level using a two-step approach. The first step is to compare the fair value of the reporting unit to the carrying value of the net assets assigned to the reporting unit. If the fair value of the reporting unit is greater than the carrying value of the net assets assigned to the reporting unit, the assigned goodwill is not considered impaired. If the fair value is less than the reporting unit’s carrying value, step two is performed to measure the amount of the impairment, if any. In the second step, the fair value of goodwill is determined by deducting the fair value of the reporting unit’s identifiable assets and liabilities from the fair value of the reporting unit as a whole, as if the reporting unit had just been acquired and the fair value was being initially allocated. If the carrying value of goodwill exceeds the implied fair value, an impairment charge would be recorded in the period the determination is made.
	As a result of the Company’s annual impairment test as of December 31, 2013 and 2012, goodwill was not considered impaired and, as such, no impairment charges were recorded.
Advertising Costs	'
	Advertising Costs
	The Company expenses advertising costs as incurred. The amount expensed during the years ended December 31, 2013, 2012 and 2011 was $4.6 million, $2.1 million and $1.9 million, respectively.
Software Development Costs	'
	Software Development Costs
	The Company capitalizes certain internal-use software development costs, consisting primarily of direct labor associated with creating the internally developed software and third-party consulting fees associated with implementing software purchased for internal use. Software development projects generally include three stages: the preliminary project stage (in which all costs are expensed as incurred), the application development stage (in which certain costs are capitalized) and the post-implementation/operation stage (in which all costs are expensed as incurred). The costs incurred during the application development stage primarily include the costs of designing the application, coding and testing of the system. Capitalized costs are amortized using the straight-line method over the estimated useful life of the software once it is ready for its intended use.
	Software development costs of $0.3 million and $0.2 million related to creating internally developed software and implementing software purchased for internal use were capitalized during the years ended December 31, 2013 and 2012, respectively, and are included in property and equipment in the accompanying consolidated balance sheets. Amortization expense related to this capitalized internally developed software was $0.1 million and $20,000 for the years ended December 31, 2013 and 2012, respectively, and is included in cost of revenue or general and administrative expense in the accompanying consolidated statements of operations. The net book value of capitalized internally developed software was $0.3 million and $0.1 million at December 31, 2013 and 2012, respectively.
	Software development costs of $1.8 million related to configuring and implementing hosted third-party software applications that the Company will use in its business operations were capitalized during the year ended December 31, 2013 and are included in property and equipment in the accompanying consolidated balance sheets. Amortization expense related to these capitalized assets was $0.1 million for the year ended December 31, 2013 and is included in general and administrative expense in the accompanying consolidated statements of operations. The net book value of these capitalized assets was $1.7 million and $0 as of December 31, 2013 and 2012, respectively.
	During the year ended December 31, 2011, the costs incurred during the application development stage were not significant and were charged to operations in the accompanying consolidated statement of operations.
Income Taxes	'
	Income Taxes
	Income taxes are accounted for under the asset and liability method of accounting. Deferred tax assets and liabilities are recognized for the future tax consequences attributable to differences between the financial statement carrying amounts of existing assets and liabilities and their respective tax bases, as well as for operating loss and tax credit carryforwards. Deferred tax assets and liabilities are measured using enacted tax rates expected to apply to taxable income in the years in which those temporary differences are expected to be recovered or settled. The effect on deferred tax assets and liabilities of a change in tax rates is recognized in the results of operations in the period that includes the enactment date. The measurement of a deferred tax asset is reduced, if necessary, by a valuation allowance if it is more likely than not that some portion or all of the deferred tax asset will not be realized.
	The Company applies the accounting guidance for uncertainties in income taxes, which prescribes a recognition threshold and measurement process for recording uncertain tax positions taken, or expected to be taken, in a tax return in the financial statements. Additionally, the guidance also prescribes the treatment for the derecognition, classification, accounting in interim periods and disclosure requirements for uncertain tax positions. The Company accrues for the estimated amount of taxes for uncertain tax positions if it is more likely than not that the Company would be required to pay such additional taxes. An uncertain tax position will be recognized if it is more likely than not to be sustained. The Company did not have any accrued interest or penalties associated with unrecognized tax positions as of December 31, 2013 and 2012.
	The Company’s policy for recording interest and penalties is to record them as a component of provision for income taxes.
Foreign Currency Translation	'
	Foreign Currency Translation
	The functional currency of the Company’s non-U.S. operations is the local currency. Assets and liabilities denominated in foreign currencies are translated into U.S. dollars at exchange rates prevailing at the balance sheet dates. Revenue and expenses are translated into U.S. dollars using the average rates of exchange prevailing during the period. Gains or losses resulting from the translation of assets and liabilities are included as a component of accumulated other comprehensive loss in stockholders’ equity (deficit). Gains and losses resulting from foreign currency transactions are recognized as other (expense) income. The Company did not have any gains or losses resulting from foreign currency transactions during the years ended December 31, 2013, 2012 and 2011.
Stock-Based Compensation	'
	Stock-Based Compensation
	The Company accounts for stock-based compensation awards based on the fair value of the award as of the grant date. The Company recognizes stock-based compensation expense using the accelerated attribution method, net of estimated forfeitures, in which compensation cost for each vesting tranche in an award is recognized ratably from the service inception date to the vesting date for that tranche.
	The Company uses the Black-Scholes option pricing model for estimating the fair value of stock options. The use of the option valuation model requires the input of highly subjective assumptions, including the fair value of the Company’s common stock prior to the IPO, the expected life of the option and the expected stock price volatility based on peer companies. Additionally, the recognition of expense requires the estimation of the number of options that will ultimately vest and the number of options that will ultimately be forfeited.
Basic and Diluted Loss per Common Share	'
	Basic and Diluted Loss per Common Share
	The Company uses the two-class method to compute net loss per common share because the Company has issued securities, other than common stock, that contractually entitled the holders to participate in dividends and earnings of the Company. The two-class method requires earnings for the period to be allocated between common stock and participating securities based upon their respective rights to receive distributed and undistributed earnings. Prior to their conversion to common shares, each series of the Company’s redeemable convertible preferred stock was entitled to participate on an as-if-converted basis in distributions, when and if declared by the board of directors, that were made to common stockholders, and as a result these shares were considered participating securities. During 2013, certain shares issued as a result of the early exercise of stock options, which were subject to repurchase by the Company, were entitled to receive non-forfeitable dividends during the vesting period and as a result were also considered participating securities.
	Under the two-class method, for periods with net income, basic net income per common share is computed by dividing the net income attributable to common stockholders by the weighted average number of shares of common stock outstanding during the period. Net income attributable to common stockholders is computed by subtracting from net income the portion of current year earnings that the participating securities would have been entitled to receive pursuant to their dividend rights had all of the year’s earnings been distributed. No such adjustment to earnings is made during periods with a net loss, as the holders of the participating securities have no obligation to fund losses. Diluted net loss per common share is computed under the two-class method by using the weighted average number of shares of common stock outstanding, plus, for periods with net income attributable to common stockholders, the potential dilutive effects of stock options and warrants. In addition, the Company analyzes the potential dilutive effect of the outstanding participating securities under the “if-converted” method when calculating diluted earnings per share, in which it is assumed that the outstanding participating securities convert into common stock at the beginning of the period. The Company reports the more dilutive of the approaches (two-class or “if-converted”) as its diluted net income per share during the period. Due to net losses for the years ended December 31, 2013, 2012 and 2011, basic and diluted loss per share were the same, as the effect of potentially dilutive securities would have been anti-dilutive.

Significant_Accounting_Policie2

Significant Accounting Policies Significant Accounting Policies (Tables)	12 Months Ended
	Dec. 31, 2013
Accounting Policies [Abstract]	'
Liabilities Measured at Fair Value on Recurring Basis	'
	The following table summarizes the conclusions reached as of December 31, 2012 (in thousands):
		Balance as of				Level 1				Level 2			Level 3
		December 31,
		2012
	Liabilities:
	Series A warrants(1)	$	88			$	—			$	—		$	88
	Series C warrants(1)	3,147				—				—			3,147
		$	3,235			$	—			$	—		$	3,235
	_______________________
	(1) In order to determine the fair value of the redeemable convertible preferred stock warrants, the Company used a hybrid of the probability-weighted expected return method (“PWERM”) and the option pricing model ("OPM"), collectively referred to as the “Hybrid Method,” for the year ended December 31, 2012. The Hybrid Method is a PWERM model in which one of the valuation scenarios is modeled using an OPM.
	Significant inputs for the OPM included an estimate of the fair value of the Series A and Series C redeemable convertible preferred stock, the remaining contractual life of the warrants, an estimate of the timing of a liquidity event, a risk-free rate of interest and an estimate of the Company’s stock volatility using the volatilities of guideline peer companies. Significant inputs for the PWERM included an estimate of the Company’s equity value, a weighted average cost of capital and an estimated probability and timing for each valuation scenario.
Changes in Company's Level 3 Instruments Measured at Fair Value on Recurring Basis	'
	The following table presents the changes in the Company’s Level 3 instruments measured at fair value on a recurring basis during the years ended December 31, 2013, 2012 and 2011 (in thousands):
		Series A												Series C
			2013				2012				2011			2013			2012			2011
	Balance as of January 1		$	88			$	113			$	63		$	3,147		$	479		$	268
	Issuance of Series C warrant		—				—				—			—			2,705			—
	Cashless exercise of warrants		(166		)		(67		)		—			(489		)	—			—
	Change in fair value of warrant liability		78				42				50			974			(37		)	211
	Reclassification of warrant liability to equity		—				—				—			(3,632		)	—			—
	Balance as of December 31		$	—			$	88			$	113		$	—		$	3,147		$	479
Changes in Allowance for Doubtful Accounts	'
	The following table presents the changes in the Company’s allowance for doubtful accounts during the years ended December 31, 2013, 2012 and 2011 (in thousands):
		Balance at				Additions				Deductions			Balance at
		Beginning				Charged To							End of
		of Period				Expense/							Period
						Against
						Revenue
	Allowance for doubtful accounts:
	Year ended December 31, 2013	$	191			$	594			$	(224	)	$	561
	Year ended December 31, 2012	115				222				(146		)	191
	Year ended December 31, 2011	192				202				(279		)	115
Schedule of Property and Equipment	'
	The estimated useful lives for significant property and equipment categories are generally as follows:
	Purchased software, including internal-use software	3 years
	Computer hardware	3 years
	Furniture and office equipment	3 to 5 years
	Leasehold improvements	Lesser of remaining lease term or useful life
	Property and equipment consisted of the following as of December 31, 2013 and 2012 (in thousands):
		2013				2012
	Purchased software, including internal-use software	$	6,103			$	3,564
	Computer hardware	12,886				9,346
	Furniture and office equipment	3,012				1,750
	Leasehold improvements	1,507				948
		23,508				15,608
	Less: accumulated depreciation	(14,420		)		(11,293		)
		$	9,088			$	4,315
Schedule of Intangible Assets	'
	The estimated useful lives used in computing amortization are as follows:
	Customer relationships	5 to 8 years
	Proprietary software	8 years
	Trade name	5 years
	Intangible assets consisted of the following at December 31, 2013 and 2012 (in thousands):
		2013
		Gross Carrying				Accumulated				Net Carrying			Weighted Average
		Amount				Amortization				Amount			Useful Life (in  years)
	Customer relationships	$	4,745			$	(4,225	)		$	520		6.5
	Proprietary software	1,010				(860		)		150			6.8
	Trade name	400				(400		)		—			5
		$	6,155			$	(5,485	)		$	670		6.5
		2012
		Gross Carrying				Accumulated				Net Carrying			Weighted Average
		Amount				Amortization				Amount			Useful Life (in  years)
	Customer relationships	$	4,745			$	(3,779	)		$	966		6.5
	Proprietary software	1,010				(771		)		239			6.8
	Trade name	400				(360		)		40			5
		$	6,155			$	(4,910	)		$	1,245		6.5

Property_and_Equipment_Tables

Property and Equipment (Tables)	12 Months Ended
	Dec. 31, 2013
Property, Plant and Equipment [Abstract]	'
Schedule of Property and Equipment	'
	The estimated useful lives for significant property and equipment categories are generally as follows:
	Purchased software, including internal-use software	3 years
	Computer hardware	3 years
	Furniture and office equipment	3 to 5 years
	Leasehold improvements	Lesser of remaining lease term or useful life
	Property and equipment consisted of the following as of December 31, 2013 and 2012 (in thousands):
		2013			2012
	Purchased software, including internal-use software	$	6,103		$	3,564
	Computer hardware	12,886			9,346
	Furniture and office equipment	3,012			1,750
	Leasehold improvements	1,507			948
		23,508			15,608
	Less: accumulated depreciation	(14,420		)	(11,293		)
		$	9,088		$	4,315

Goodwill_and_Intangible_Assets1

Goodwill and Intangible Assets (Tables)	12 Months Ended
	Dec. 31, 2013
Goodwill and Intangible Assets Disclosure [Abstract]	'
Schedule of Intangible Assets	'
	The estimated useful lives used in computing amortization are as follows:
	Customer relationships	5 to 8 years
	Proprietary software	8 years
	Trade name	5 years
	Intangible assets consisted of the following at December 31, 2013 and 2012 (in thousands):
		2013
		Gross Carrying		Accumulated			Net Carrying		Weighted Average
		Amount		Amortization			Amount		Useful Life (in  years)
	Customer relationships	$	4,745	$	(4,225	)	$	520	6.5
	Proprietary software	1,010		(860		)	150		6.8
	Trade name	400		(400		)	—		5
		$	6,155	$	(5,485	)	$	670	6.5
		2012
		Gross Carrying		Accumulated			Net Carrying		Weighted Average
		Amount		Amortization			Amount		Useful Life (in  years)
	Customer relationships	$	4,745	$	(3,779	)	$	966	6.5
	Proprietary software	1,010		(771		)	239		6.8
	Trade name	400		(360		)	40		5
		$	6,155	$	(4,910	)	$	1,245	6.5
Expected Future Amortization Expense	'
	As of December 31, 2013, expected amortization expense over the remaining intangible asset lives is as follows (in thousands):
	2014	$	395
	2015	275
	Total	$	670

Commitments_and_Contingencies_

Commitments and Contingencies (Tables)	12 Months Ended
	Dec. 31, 2013
Commitments and Contingencies Disclosure [Abstract]	'
Schedule of Future Minimum Lease Payments	'
	The Company leases office facilities and certain equipment under non-cancelable operating and capital leases. Future minimum lease payments are as follows (in thousands):
		Operating Leases		Capital Leases
	Year Ending December 31,
	2014	$	1,973	$	1,570
	2015	1,997		1,172
	2016	1,972		450
	2017	1,738		3
	2018	1,827		1
	Thereafter	5,810		—
	Total minimum lease payments	$	15,317	3,196
	Less: imputed interest			(251		)
	Less: current portion			(1,387		)
	Capital lease obligations, net of current portion			$	1,558

Debt_Tables

Debt (Tables)	12 Months Ended
	Dec. 31, 2013
Debt Disclosure [Abstract]	'
Schedule of Long-term Debt	'
	Long-term debt consisted of the following at December 31, 2013 and 2012 (in thousands):
		2013		2012
	Revolving line of credit	$	—	$	3,300
	Equipment line of credit	—		70
	Subordinated loan	—		10,000
	Debt discount	—		(2,398		)
	Total debt	—		10,972
	Current portion of long-term debt	—		3,370
	Debt, net of current portion	$	—	$	7,602

Income_Taxes_Tables

Income Taxes (Tables)	12 Months Ended
	Dec. 31, 2013
Income Tax Disclosure [Abstract]	'
Components of Loss before Income Taxes	'
	The components of loss before income taxes for the years ended December 31 2013, 2012 and 2011 were as follows (in thousands):
		2013				2012				2011
	Domestic	$	(7,222	)		$	1,821			$	1,061
	Foreign	(13,203		)		(6,824		)		(4,874		)
	Total loss before income taxes	$	(20,425	)		$	(5,003	)		$	(3,813	)
Schedule of Provision for Income Tax Expense (Benefit)	'
	The provision for income tax expense (benefit) included the following for the years ended December 31, 2013, 2012 and 2011 (in thousands):
		2013				2012				2011
	Current:
	Federal	$	22			$	46			$	4
	State	193				55				(2		)
	Foreign	—				(201		)		—
	Total	215				(100		)		2
	Deferred:
	Federal	(26		)		28				47
	State	14				2				2
	Total	(12		)		30				49
	Total tax expense (benefit)	$	203			$	(70	)		$	51
Components of Net Deferred Tax Assets (Liabilities)	'
	The components of the Company’s net deferred tax assets (liabilities) as of December 31, 2013, 2012 and 2011 were as follows (in thousands):
		2013				2012				2011
	Current:
	Deferred tax assets:
	Other assets	$	832			$	585			$	576
	Valuation allowance	(726		)		(539		)		(529		)
	Total deferred tax assets	106				46				47
	Deferred tax liabilities:
	Other liabilities	71				11				3
	Net deferred tax asset, current	$	35			$	35			$	44
	Noncurrent:
	Deferred tax assets:
	Domestic tax loss carryforwards	$	18,898			$	17,288			$	18,067
	Foreign tax loss carryforwards	7,673				5,526				4,202
	Tax credits	78				57				11
	Other assets	866				900				1,149
	Valuation allowance	(26,206		)		(22,040		)		(21,615		)
	Total deferred tax assets	1,309				1,731				1,814
	Deferred tax liabilities:
	Fixed assets	1,149				1,214				518
	Other liabilities	383				752				1,510
	Total deferred tax liabilities	1,532				1,966				2,028
	Net deferred tax liability, noncurrent	$	(223	)		$	(235	)		$	(214	)
Schedule of Effective Income Tax Rate Reconciliation	'
	A reconciliation of the difference between the effective income tax rate and the statutory federal income tax rate for the years ended December 31, 2013, 2012 and 2011 is as follows:
		2013			2012			2011
	U.S. statutory federal rate	34	%		34	%		34	%
	Increase (decrease) resulting from:
	State taxes, net of federal benefit	1.6			(0.8	)		0.5
	Nondeductible expenses	(5.2	)		(9.2	)		(6.2	)
	Effect of foreign tax rate differential	(8.0	)		(13.3	)		(10.8	)
	NOL adjustment	—			—			(35.1	)
	Change in valuation allowance	(22.4	)		(6.6	)		15.8
	Other	(1.0	)		(2.7	)		0.6
	Effective tax rate	(1.0	)%		1.4	%		(1.2	)%

Stockholders_Equity_Deficit_an1

Stockholders' Equity (Deficit) and Redeemable Convertible Preferred Stock (Tables)	12 Months Ended
	Dec. 31, 2013
Temporary Equity [Line Items]	'
Summary of Issuances of Redeemable Convertible Preferred Stock	'
	The following table summarizes the issuances of redeemable convertible preferred stock prior to the IPO:
	Name		Price per			Number of		Conversion
			Share			Shares		Price per Share
	Series A		$	0.2		93,966,024		$	3.2
	Series B		$	0.44		40,641,227		$	7.04
	Series B-1		$	0.53		5,660,378		$	8.48
	Series C		$	0.69		74,156,709		$	10.96
Redeemable Convertible Preferred Stock [Member]	'
Temporary Equity [Line Items]	'
Summary of Activity for Redeemable Convertible Preferred Stock	'
	The following table presents a summary of activity for the Preferred Stock issued and outstanding for the years ended December 31, 2013, 2012 and 2011 (in thousands):
		Redeemable Convertible Preferred Stock
		Series A			Series B			Series B-1			Series C			Total
														Amount
	Balance, January 1, 2011	18,805			17,989			2,998			50,571			90,363
	Accretion of issuance costs on Preferred Stock	11			8			1			30			50
	Balance, December 31, 2011	18,816			17,997			2,999			50,601			90,413
	Cashless exercise of warrants	67			—			—			—			67
	Accretion of issuance costs on Preferred Stock	4			3			1			7			15
	Balance, December 31, 2012	$	18,887		$	18,000		$	3,000		$	50,608		$	90,495
	Cashless exercise of warrants	166			—			—			489			655
	Conversion of Preferred Stock into common stock	(19,053		)	(18,000		)	(3,000		)	(51,097		)	(91,150		)
	Balance, December 31, 2013	$	—		$	—		$	—		$	—		$	—

Equity_Incentive_Plans_and_Sto1

Equity Incentive Plans and Stock-Based Compensation (Tables)	12 Months Ended
	Dec. 31, 2013
Disclosure of Compensation Related Costs, Share-based Payments [Abstract]	'
Summary of Stock-Based Compensation Expense	'
	Stock-based compensation expense related to stock options is included in the following line items in the accompanying consolidated statements of operations for the years ended December 31, 2013, 2012 and 2011 (in thousands):
		2013				2012			2011
	Cost of revenue	$	204			$	64		$	15
	Sales and marketing	607				224			16
	Research and development	348				105			58
	General and administrative	940				245			111
		$	2,099			$	638		$	200
Summary of Weighted-Average Assumptions Used for Estimating Fair Value of Stock Granted	'
	The following table summarizes the assumptions used for estimating the fair value of stock options granted for the years ended December 31, 2013, 2012 and 2011:
		2013		2012		2011
	Risk-free interest rate	0.3% - 1.7%		0.1% - 0.9%		0.4% - 2.0%
	Expected term (years)	5.00 - 6.25		4.00 - 6.25		6.25
	Expected volatility	43% - 59%		49% - 60%		28% - 56%
	Dividend yield	0%		0%		0%
Summary of Stock Option Activity	'
	The following is a summary of the option activity for the year ended December 31, 2013:
		Number of			Weighted Average			Weighted		Aggregate
		Options			Exercise Price			Average		Intrinsic Value
								Remaining
								Contractual
								Term
								(in years)		(in thousands)
	Outstanding balance at December 31, 2012	2,202,712			$	3.84
	Granted	722,625			12.74
	Exercised	(727,318	)		3.36
	Forfeited	(104,042	)		8.3
	Expired	(25,336	)		2.67
	Outstanding balance at December 31, 2013	2,068,641			$	6.95		7.8		$	71,914
	Exercisable at December 31, 2013	938,151			$	3.3		6.6		$	36,039
	Vested and expected to vest at December 31, 2013	1,813,530			$	6.62		7.68		$	63,636

Net_Loss_Per_Share_Tables

Net Loss Per Share (Tables)	12 Months Ended
	Dec. 31, 2013
Earnings Per Share [Abstract]	'
Schedule of Securities Excluded from Calculation of Weighted Average Common Shares Outstanding	'
	The following securities have been excluded from the calculation of weighted average common shares outstanding because the effect is anti-dilutive for the years ended December 31, 2013, 2012 and 2011:
		2013	2012	2011
	Redeemable convertible preferred stock:
	Series A	—	5,863,825	5,857,864
	Series B	—	2,540,066	2,540,066
	Series B-1	—	353,767	353,767
	Series C	—	4,617,513	4,617,513
	Warrants to purchase common stock	986,784	1,616,113	1,616,113
	Warrants to purchase Series A redeemable convertible preferred stock	—	10,937	21,484
	Warrants to purchase Series C redeemable convertible preferred stock	—	286,625	89,750
	Stock options	2,068,641	2,202,712	1,936,191

Segment_and_Geographic_Informa1

Segment and Geographic Information (Tables)	12 Months Ended
	Dec. 31, 2013
Segment Reporting [Abstract]	'
Summary of Revenue by Geography	'
	The following table summarizes revenue by geography for the years ended December 31, 2013, 2012 and 2011 (in thousands):
		2013		2012		2011
	Revenue:
	Domestic	$	53,832	$	42,140	$	34,805
	International	14,172		11,447		8,765
	Total	$	68,004	$	53,587	$	43,570

Selected_Quarterly_Information1

Selected Quarterly Information (unaudited) (Tables)	12 Months Ended
	Dec. 31, 2013
Quarterly Financial Information Disclosure [Abstract]	'
Schedule of quarterly financial information	'
		Three Months Ended
		March 31,			June 30,			September 30,			December 31,
		2013			2013			2013			2013
		(in thousands, except per share amounts)
	Revenue	$	14,922		$	15,976		$	16,620		$	20,486
	Gross profit	10,975			11,507			12,065			15,369
	Loss from operations	(2,137		)	(3,496		)	(3,741		)	(4,991		)
	Net loss	(2,730		)	(4,997		)	(4,292		)	(8,609		)
	Net loss per share:
	Basic and diluted	(2.10		)	(0.56		)	(0.20		)	(0.38		)
		Three Months Ended
		March 31,			June 30,			September 30,			December 31,
		2012			2012			2012			2012
		(in thousands, except per share amounts)
	Revenue	$	12,166		$	12,408		$	13,020		$	15,993
	Gross profit	8,920			8,778			9,189			11,951
	(Loss) income from operations	(809		)	(2,347		)	(1,517		)	824
	Net (loss) income	(851		)	(2,750		)	(1,958		)	626
	Net (loss) income per share:
	Basic and diluted	(0.74		)	(2.39		)	(1.68		)	0.04

Significant_Accounting_Policie3

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

0 Months Ended

12 Months Ended

0 Months Ended

29-May-13

9-May-13

Dec. 31, 2013

Dec. 31, 2012

Dec. 31, 2011

Dec. 31, 2013

Dec. 31, 2012

Dec. 31, 2013

Dec. 31, 2012

29-May-13

Dec. 31, 2008

29-May-13

Nov. 12, 2013

29-May-13

segment

Software and Software Development Costs [Member]

Software and Software Development Costs [Member]

Hosted Software Configuration Costs [Member]

Hosted Software Configuration Costs [Member]

Redeemable Convertible Preferred Stock [Member]

Common Stock [Member]

Common Stock [Member]

Registered Public Offering [Member]

Initial Public Offering [Member]

Series C Warrants [Member]

Series C Warrants [Member]

Significant Accounting Policies [Line Items]

'

'

'

'

'

'

'

'

'

'

'

'

'

'

Reverse stock split ratio

'

0.0625

'

'

'

'

'

'

'

'

'

'

'

'

Sale of common stock

'

'

'

'

'

'

'

'

'

'

'

'

1,000,000

6,612,500

Offering price

'

'

'

'

'

'

'

'

'

'

'

'

$34

$14

Net proceeds from common stock

'

'

$113,848,000

'

'

'

'

'

'

'

'

'

$31,900,000

$82,000,000

Underwriting discounts and commissions

'

'

'

'

'

'

'

'

'

'

'

'

1,600,000

6,500,000

Offering expenses

'

'

'

'

'

'

'

'

'

'

'

'

500,000

4,100,000

Warrants to purchase stock

'

'

'

'

'

'

'

'

'

206,038

1,616,113

216,491

'

'

Conversion of redeemable convertible preferred stock to common stock, shares

13,401,499

'

'

'

'

'

'

'

'

'

'

'

'

'

Preferred stock, shares authorized

5,000,000

'

5,000,000

0

'

'

'

'

'

'

'

'

'

'

Common stock, shares authorized

100,000,000

'

100,000,000

303,500,000

'

'

'

'

'

'

'

'

'

'

Other receivables

'

'

1,700,000

1,500,000

'

'

'

'

'

'

'

'

'

'

Deferred offering costs

'

'

0

2,300,000

'

'

'

'

'

'

'

'

'

'

Number of reportable segments

'

'

1

'

'

'

'

'

'

'

'

'

'

'

Advertising expense

'

'

4,600,000

2,100,000

1,900,000

'

'

'

'

'

'

'

'

'

Capitalized computer software, additions

'

'

'

'

'

300,000

200,000

1,800,000

'

'

'

'

'

'

Amortization expense on capitalized internally developed software

'

'

'

'

'

100,000

20,000

100,000

'

'

'

'

'

'

Capitalized internally developed software, net book value

'

'

'

'

'

$300,000

$100,000

$1,700,000

$0

'

'

'

'

'

Significant_Accounting_Policie4

Significant Accounting Policies - Restricted Cash (Details) (United States, USD $)	Dec. 31, 2013	Dec. 31, 2012
In Millions, unless otherwise specified
United States	'	'
Restricted Cash and Cash Equivalents Items [Line Items]	'	'
Restricted cash	$0.70	$0.70
Restricted cash used as collateral	$0.60	$0.60

Significant_Accounting_Policie5

Significant Accounting Policies - Assets and Liabilities Measured at Fair Value on Recurring Basis (Details) (USD $)	Dec. 31, 2013	Dec. 31, 2012
In Thousands, unless otherwise specified
Fair Value Of Assets And Liabilities Measured On Recurring Basis (Line Items)	'	'
Warrants and Rights Outstanding	$0	$3,235
Level 1 [Member]	'	'
Fair Value Of Assets And Liabilities Measured On Recurring Basis (Line Items)	'	'
Warrants and Rights Outstanding	'	0
Level 2 [Member]	'	'
Fair Value Of Assets And Liabilities Measured On Recurring Basis (Line Items)	'	'
Warrants and Rights Outstanding	'	0
Level 3 [Member]	'	'
Fair Value Of Assets And Liabilities Measured On Recurring Basis (Line Items)	'	'
Warrants and Rights Outstanding	'	3,235
Series A Warrants [Member]	'	'
Fair Value Of Assets And Liabilities Measured On Recurring Basis (Line Items)	'	'
Warrants and Rights Outstanding	'	88	[1]
Series A Warrants [Member] | Level 1 [Member]	'	'
Fair Value Of Assets And Liabilities Measured On Recurring Basis (Line Items)	'	'
Warrants and Rights Outstanding	'	0	[1]
Series A Warrants [Member] | Level 2 [Member]	'	'
Fair Value Of Assets And Liabilities Measured On Recurring Basis (Line Items)	'	'
Warrants and Rights Outstanding	'	0	[1]
Series A Warrants [Member] | Level 3 [Member]	'	'
Fair Value Of Assets And Liabilities Measured On Recurring Basis (Line Items)	'	'
Warrants and Rights Outstanding	'	88	[1]
Series C Warrants [Member]	'	'
Fair Value Of Assets And Liabilities Measured On Recurring Basis (Line Items)	'	'
Warrants and Rights Outstanding	'	3,147	[1]
Series C Warrants [Member] | Level 1 [Member]	'	'
Fair Value Of Assets And Liabilities Measured On Recurring Basis (Line Items)	'	'
Warrants and Rights Outstanding	'	0	[1]
Series C Warrants [Member] | Level 2 [Member]	'	'
Fair Value Of Assets And Liabilities Measured On Recurring Basis (Line Items)	'	'
Warrants and Rights Outstanding	'	0	[1]
Series C Warrants [Member] | Level 3 [Member]	'	'
Fair Value Of Assets And Liabilities Measured On Recurring Basis (Line Items)	'	'
Warrants and Rights Outstanding	'	$3,147	[1]
[1]	In order to determine the fair value of the redeemable convertible preferred stock warrants, the Company used a hybrid of the probability-weighted expected return method (bPWERMb) and the option pricing model ("OPM"), collectively referred to as the bHybrid Method,b for the year ended DecemberB 31, 2012. The Hybrid Method is a PWERM model in which one of the valuation scenarios is modeled using an OPM. Significant inputs for the OPM included an estimate of the fair value of the SeriesB A and SeriesB C redeemable convertible preferred stock, the remaining contractual life of the warrants, an estimate of the timing of a liquidity event, a risk-free rate of interest and an estimate of the Companybs stock volatility using the volatilities of guideline peer companies. Significant inputs for the PWERM included an estimate of the Companybs equity value, a weighted average cost of capital and an estimated probability and timing for each valuation scenario.

Significant_Accounting_Policie6

Significant Accounting Policies Significant Accounting Policies - Changes in Company's Level 3 Instruments Measured at Fair Value on Recurring Basis (Details) (USD $)	0 Months Ended	12 Months Ended
In Thousands, unless otherwise specified	29-May-13	Dec. 31, 2013	Dec. 31, 2012	Dec. 31, 2011
Fair Value, Liabilities Measured on Recurring Basis, Unobservable Input Reconciliation, Calculation [Roll Forward]	'	'	'	'
Reclassification of warrant liability to equity	($3,632)	($3,632)	$0	$0
Series A Warrants [Member]	'	'	'	'
Fair Value, Liabilities Measured on Recurring Basis, Unobservable Input Reconciliation, Calculation [Roll Forward]	'	'	'	'
Beginning Balance	'	88	113	63
Issuance of Series C warrant	'	0	0	0
Cashless exercise of warrants	'	-166	-67	0
Change in fair value of warrant liability	'	78	42	50
Reclassification of warrant liability to equity	'	0	0	0
Ending Balance	'	0	88	113
Series C Warrants [Member]	'	'	'	'
Fair Value, Liabilities Measured on Recurring Basis, Unobservable Input Reconciliation, Calculation [Roll Forward]	'	'	'	'
Beginning Balance	'	3,147	479	268
Issuance of Series C warrant	'	0	2,705	0
Cashless exercise of warrants	'	-489	0	0
Change in fair value of warrant liability	'	974	-37	211
Reclassification of warrant liability to equity	'	-3,632	0	0
Ending Balance	'	$0	$3,147	$479

Significant_Accounting_Policie7

Significant Accounting Policies - Allowance for Doubtful Accounts (Details) (Allowance for Doubtful Accounts [Member], USD $)	12 Months Ended
In Thousands, unless otherwise specified	Dec. 31, 2013	Dec. 31, 2012	Dec. 31, 2011
Allowance for Doubtful Accounts [Member]	'	'	'
Allowance for Doubtful Accounts Receivable [Roll Forward]	'	'	'
Balance at Beginning of Period	$191	$115	$192
Additions Charged to Expense/Against Revenue	594	222	202
Deductions	-224	-146	-279
Balance at End of Period	$561	$191	$115

Significant_Accounting_Policie8

Significant Accounting Policies - Estimated Useful Lives for Significant Property and Equipment (Details)	12 Months Ended
	Dec. 31, 2013
Purchased software, including internal-use software [Member]	'
Property, Plant and Equipment [Line Items]	'
Estimated useful life	'3 years
Computer hardware [Member]	'
Property, Plant and Equipment [Line Items]	'
Estimated useful life	'3 years
Minimum [Member] | Furniture and office equipment [Member]	'
Property, Plant and Equipment [Line Items]	'
Estimated useful life	'3 years
Maximum [Member] | Furniture and office equipment [Member]	'
Property, Plant and Equipment [Line Items]	'
Estimated useful life	'5 years

Significant_Accounting_Policie9

Significant Accounting Policies - Estimated Useful Lives Used in Computing Amortization (Detail)	12 Months Ended
	Dec. 31, 2013
Customer Relationships [Member] | Minimum [Member]	'
Finite-Lived Intangible Assets [Line Items]	'
Estimated useful life of intangible asset	'5 years
Customer Relationships [Member] | Maximum [Member]	'
Finite-Lived Intangible Assets [Line Items]	'
Estimated useful life of intangible asset	'8 years
Proprietary Software [Member]	'
Finite-Lived Intangible Assets [Line Items]	'
Estimated useful life of intangible asset	'8 years
Trade Name [Member]	'
Finite-Lived Intangible Assets [Line Items]	'
Estimated useful life of intangible asset	'5 years

Property_and_Equipment_Additio

Property and Equipment - Additional Information (Details) (USD $)	12 Months Ended
In Millions, unless otherwise specified	Dec. 31, 2013	Dec. 31, 2012	Dec. 31, 2011
Property, Plant and Equipment [Abstract]	'	'	'
Depreciation expense	$3.10	$2.10	$1.20

Property_and_Equipment_Summary

Property and Equipment - Summary of Property and Equipment (Details) (USD $)	Dec. 31, 2013	Dec. 31, 2012
In Thousands, unless otherwise specified
Property, Plant and Equipment [Line Items]	'	'
Property and equipment, gross	$23,508	$15,608
Less: accumulated depreciation	-14,420	-11,293
Property and equipment, net	9,088	4,315
Purchased software, including internal use software [Member]	'	'
Property, Plant and Equipment [Line Items]	'	'
Property and equipment, gross	6,103	3,564
Computer hardware [Member]	'	'
Property, Plant and Equipment [Line Items]	'	'
Property and equipment, gross	12,886	9,346
Furniture and office equipment [Member]	'	'
Property, Plant and Equipment [Line Items]	'	'
Property and equipment, gross	3,012	1,750
Leasehold improvements [Member]	'	'
Property, Plant and Equipment [Line Items]	'	'
Property and equipment, gross	$1,507	$948

Goodwill_and_Intangible_Assets2

Goodwill and Intangible Assets - Additional Information (Details) (USD $)	12 Months Ended
	Dec. 31, 2013	Dec. 31, 2012	Dec. 31, 2011
Goodwill and Intangible Assets Disclosure [Abstract]	'	'	'
Amortization expense	$600,000	$800,000	$800,000
Goodwill, Period Increase (Decrease)	$0	$0	'

Goodwill_and_Intangible_Assets3

Goodwill and Intangible Assets - Summary of Intangible Assets (Details) (USD $)	12 Months Ended
In Thousands, unless otherwise specified	Dec. 31, 2013	Dec. 31, 2012
Finite-Lived Intangible Assets [Line Items]	'	'
Gross Carrying Amount	$6,155	$6,155
Accumulated Amortization	-5,485	-4,910
Net Carrying Amount	670	1,245
Weighted Average Useful Life (in years)	'6 years 6 months	'6 years 6 months
Customer Relationships [Member]	'	'
Finite-Lived Intangible Assets [Line Items]	'	'
Gross Carrying Amount	4,745	4,745
Accumulated Amortization	-4,225	-3,779
Net Carrying Amount	520	966
Weighted Average Useful Life (in years)	'6 years 6 months	'6 years 6 months
Proprietary Software [Member]	'	'
Finite-Lived Intangible Assets [Line Items]	'	'
Gross Carrying Amount	1,010	1,010
Accumulated Amortization	-860	-771
Net Carrying Amount	150	239
Weighted Average Useful Life (in years)	'6 years 9 months 18 days	'6 years 9 months 18 days
Trade Name [Member]	'	'
Finite-Lived Intangible Assets [Line Items]	'	'
Gross Carrying Amount	400	400
Accumulated Amortization	-400	-360
Net Carrying Amount	$0	$40
Weighted Average Useful Life (in years)	'5 years 0 months	'5 years 0 months

Goodwill_and_Intangible_Assets4

Goodwill and Intangible Assets - Expected Amortization Expense (Details) (USD $)	Dec. 31, 2013	Dec. 31, 2012
In Thousands, unless otherwise specified
Goodwill and Intangible Assets Disclosure [Abstract]	'	'
2014	$395	'
2015	275	'
Net Carrying Amount	$670	$1,245

Commitments_and_Contingencies_1

Commitments and Contingencies - Future Minimum Lease Payments (Details) (USD $)	Dec. 31, 2013	Dec. 31, 2012
In Thousands, unless otherwise specified
Operating Leases	'	'
2014	$1,973	'
2015	1,997	'
2016	1,972	'
2017	1,738	'
2018	1,827	'
Thereafter	5,810	'
Total minimum lease payments	15,317	'
Capital Leases	'	'
2014	1,570	'
2015	1,172	'
2016	450	'
2017	3	'
2018	1	'
Thereafter	0	'
Total minimum lease payments	3,196	'
Less: imputed interest	-251	'
Less: current portion	-1,387	'
Capital lease obligations, net of current portion	$1,558	$1,136

Commitments_and_Contingencies_2

Commitments and Contingencies - Capital Leases (Details) (USD $)	Dec. 31, 2013	Dec. 31, 2012
In Millions, unless otherwise specified
Commitments and Contingencies Disclosure [Abstract]	'	'
Fixed assets under capital leases, gross	$4.20	$2.20
Fixed assets under capital leases, net	$2.70	$1.70

Commitments_and_Contingencies_3

Commitments and Contingencies - Operating Leases (Details) (USD $)	12 Months Ended
	Dec. 31, 2013	Dec. 31, 2012	Dec. 31, 2011	Dec. 31, 2013	Jan. 31, 2011
				Morrisville Lease [Member]	Morrisville Lease [Member]
Property Subject to or Available for Operating Lease [Line Items]	'	'	'	'	'
Deferred rent	$1,200,000	$1,100,000	'	'	'
Lease incentive obligation	'	'	'	'	200,000
Total remaining lease payments	15,317,000	'	'	9,800,000	'
Rent expense	$1,800,000	$1,700,000	$1,100,000	'	'

Debt_Schedule_of_Longterm_Debt

Debt - Schedule of Long-term Debt (Details) (USD $)	Dec. 31, 2013	Dec. 31, 2012
In Thousands, unless otherwise specified
Debt Instrument [Line Items]	'	'
Debt discount	$0	($2,398)
Total debt	0	10,972
Current portion of long-term debt	0	3,370
Debt, net of current portion	0	7,602
Subordinated Loan [Member]	'	'
Debt Instrument [Line Items]	'	'
Long-term Debt, Gross	0	10,000
Revolving Credit Facility [Member] | Line of Credit [Member]	'	'
Debt Instrument [Line Items]	'	'
Long-term Debt, Gross	0	3,300
Equipment Line of Credit [Member] | Line of Credit [Member]	'	'
Debt Instrument [Line Items]	'	'
Long-term Debt, Gross	$0	$70

Debt_Loan_and_Security_Agreeme

Debt - Loan and Security Agreement (Details) (December 2009 Loan and Security Agreement Debt [Member], USD $)	Dec. 31, 2013	Jul. 31, 2012	Dec. 31, 2009	Dec. 31, 2011	Jul. 31, 2012	Dec. 31, 2009	Jun. 30, 2010
		Revolving Credit Facility [Member]	Revolving Credit Facility [Member]	Revolving Credit Facility [Member]	Revolving Credit Facility [Member]	Revolving Credit Facility [Member]	Equipment Line of Credit [Member]
					Prime Rate [Member]	Prime Rate [Member]
Debt Instrument [Line Items]	'	'	'	'	'	'	'
Maximum borrowing capacity	'	$6,000,000	$4,300,000	'	'	'	$1,000,000
Term of debt	'	'	'364 days	'	'	'	'
Proceeds from line of credit	'	'	2,300,000	1,000,000	'	'	'
Basis spread on variable rate	'	'	'	'	1.00%	0.75%	'
Interest rate	'	'	4.75%	'	'	'	6.50%
Increase in borrowing capacity	'	1,700,000	'	'	'	'	'
Payment of principal plus interest, term	'	'	'	'	'	'	'36 months
Future principal payments	$0	'	'	'	'	'	'

Debt_Subordinated_Debt_Details

Debt - Subordinated Debt (Details) (USD $)	12 Months Ended			1 Months Ended
	Dec. 31, 2013	Dec. 31, 2012	Dec. 31, 2011	Nov. 30, 2013	Dec. 31, 2012	Mar. 31, 2012	Mar. 31, 2012	Mar. 31, 2012
				March 2012 Loan and Security Agreement Debt [Member]	March 2012 Loan and Security Agreement Debt [Member]	March 2012 Loan and Security Agreement Debt [Member]	March 2012 Loan and Security Agreement Debt [Member]	March 2012 Loan and Security Agreement Debt [Member]
				Subordinated Loan [Member]	Subordinated Loan [Member]	Subordinated Loan [Member]	Minimum [Member]	Maximum [Member]
							Subordinated Loan [Member]	Subordinated Loan [Member]
Debt Instrument [Line Items]	'	'	'	'	'	'	'	'
Borrowing capacity	'	'	'	'	'	'	$5,000,000	$10,000,000
Interest rate	'	'	'	'	'	10.50%	'	'
Debt borrowed	'	'	'	'	5,000,000	5,000,000	'	'
Early repayment of subordinated debt	'	'	'	11,300,000	'	'	'	'
Payment of debt extinguishment costs	1,200,000	0	0	1,200,000	'	'	'	'
Loss on extinguishment of debt	$3,112,000	$0	$0	'	'	'	'	'

Income_Taxes_Additional_Inform

Income Taxes - Additional Information (Details) (USD $)	12 Months Ended
	Dec. 31, 2013	Dec. 31, 2012	Dec. 31, 2011
	return
Income Tax Disclosure [Abstract]	'	'	'
Income tax expense (benefit)	$203,000	($70,000)	$51,000
Undistributed earnings of foreign subsidiaries	800,000	800,000	800,000
Unrecognized tax benefits, income tax penalties and interest accrued	$0	$0	'
Income tax returns under examination, number	0	'	'

Income_Taxes_Components_of_Los

Income Taxes - Components of Loss Before Income Taxes (Details) (USD $)	12 Months Ended
In Thousands, unless otherwise specified	Dec. 31, 2013	Dec. 31, 2012	Dec. 31, 2011
Income Tax Disclosure [Abstract]	'	'	'
Domestic	($7,222)	$1,821	$1,061
Foreign	-13,203	-6,824	-4,874
Loss before income taxes	($20,425)	($5,003)	($3,813)

Income_Taxes_Provision_for_Inc

Income Taxes - Provision for Income Tax Expense (Details) (USD $)	12 Months Ended
In Thousands, unless otherwise specified	Dec. 31, 2013	Dec. 31, 2012	Dec. 31, 2011
Current:	'	'	'
Federal	$22	$46	$4
State	193	55	-2
Foreign	0	-201	0
Total	215	-100	2
Deferred:	'	'	'
Federal	-26	28	47
State	14	2	2
Total	-12	30	49
Total tax expense (benefit)	$203	($70)	$51

Income_Taxes_Components_of_Net

Income Taxes - Components of Net Deferred Tax Assets (Liabilities) (Details) (USD $)	Dec. 31, 2013	Dec. 31, 2012	Dec. 31, 2011
In Thousands, unless otherwise specified
Deferred tax assets:	'	'	'
Other assets	$832	$585	$576
Valuation allowance	-726	-539	-529
Total deferred tax assets	106	46	47
Deferred tax liabilities:	'	'	'
Other liabilities	71	11	3
Net deferred tax asset, current	35	35	44
Deferred tax assets:	'	'	'
Domestic tax loss carryforwards	18,898	17,288	18,067
Foreign tax loss carryforwards	7,673	5,526	4,202
Tax credits	78	57	11
Other assets	866	900	1,149
Valuation allowance	-26,206	-22,040	-21,615
Total deferred tax assets	1,309	1,731	1,814
Deferred tax liabilities:	'	'	'
Fixed assets	1,149	1,214	518
Other liabilities	383	752	1,510
Total deferred tax liabilities	1,532	1,966	2,028
Net deferred tax liability, noncurrent	($223)	($235)	($214)

Income_Taxes_Operating_Loss_Ca

Income Taxes - Operating Loss Carryforwards (Details) (USD $)	12 Months Ended
In Millions, unless otherwise specified	Dec. 31, 2013	Dec. 31, 2013	Dec. 31, 2012	Dec. 31, 2011	Dec. 31, 2013	Dec. 31, 2012	Dec. 31, 2011	Dec. 31, 2013	Dec. 31, 2012	Dec. 31, 2011
		Federal [Member]	Federal [Member]	Federal [Member]	State [Member]	State [Member]	State [Member]	Foreign [Member]	Foreign [Member]	Foreign [Member]
Operating Loss Carryforwards [Line Items]	'	'	'	'	'	'	'	'	'	'
Operating loss carryforwards	'	$62.50	$46.30	$48.80	$55.20	$45.10	$44.80	$25.10	$16.40	$12.40
Carryforward related to excess stock option benefits	12	'	'	'	'	'	'	'	'	'
Increase in valuation allowance	4.4	'	'	'	'	'	'	'	'	'
Tax benefit related to NOL carryforwards	$0	'	'	'	'	'	'	'	'	'

Income_Taxes_Effective_Income_

Income Taxes - Effective Income Tax Reconciliation (Details)	12 Months Ended
	Dec. 31, 2013	Dec. 31, 2012	Dec. 31, 2011
Income Tax Disclosure [Abstract]	'	'	'
U.S. statutory federal rate	34.00%	34.00%	34.00%
Increase (decrease) resulting from:	'	'	'
State taxes, net of federal benefit	1.60%	-0.80%	0.50%
Nondeductible expenses	-5.20%	-9.20%	-6.20%
Effect of foreign tax rate differential	-8.00%	-13.30%	-10.80%
NOL adjustment	0.00%	0.00%	-35.10%
Change in valuation allowance	-22.40%	-6.60%	15.80%
Other	-1.00%	-2.70%	0.60%
Effective tax rate	-1.00%	1.40%	-1.20%

Stockholders_Equity_Deficit_an2

Stockholders' Equity (Deficit) and Redeemable Convertible Preferred Stock - Redeemable Preferred Stock (Details) (USD $)	Dec. 31, 2013	28-May-13	Dec. 31, 2012
Redeemable Convertible Series A Preferred Stock [Member]	'	'	'
Temporary Equity [Line Items]	'	'	'
Price per Share	'	$0.20	'
Number of Shares	0	93,966,024	93,821,393
Conversion Price per Share	'	$3.20	'
Redeemable Convertible Series B Preferred Stock [Member]	'	'	'
Temporary Equity [Line Items]	'	'	'
Price per Share	'	$0.44	'
Number of Shares	0	40,641,227	40,641,227
Conversion Price per Share	'	$7.04	'
Redeemable Convertible Series B-1 Preferred Stock [Member]	'	'	'
Temporary Equity [Line Items]	'	'	'
Price per Share	'	$0.53	'
Number of Shares	0	5,660,378	5,660,378
Conversion Price per Share	'	$8.48	'
Redeemable Convertible Series C Preferred Stock [Member]	'	'	'
Temporary Equity [Line Items]	'	'	'
Price per Share	'	$0.69	'
Number of Shares	0	74,156,709	73,880,351
Conversion Price per Share	'	$10.96	'

Stockholders_Equity_Deficit_an3

Stockholders' Equity (Deficit) and Redeemable Convertible Preferred Stock - Summary of Activity (Details) (USD $)	12 Months Ended
In Thousands, unless otherwise specified	Dec. 31, 2013	Dec. 31, 2012	Dec. 31, 2011
Increase (Decrease) in Temporary Equity [Roll Forward]	'	'	'
Beginning balance	$90,495	$90,413	$90,363
Cashless exercise of warrants	655	67	'
Accretion of issuance costs on Preferred Stock	0	15	50
Conversion of Preferred Stock into common stock	-91,150	0	0
Ending balance	0	90,495	90,413
Redeemable Convertible Series A Preferred Stock [Member]	'	'	'
Increase (Decrease) in Temporary Equity [Roll Forward]	'	'	'
Beginning balance	18,887	18,816	18,805
Cashless exercise of warrants	166	67	'
Accretion of issuance costs on Preferred Stock	'	4	11
Conversion of Preferred Stock into common stock	-19,053	'	'
Ending balance	0	18,887	18,816
Redeemable Convertible Series B Preferred Stock [Member]	'	'	'
Increase (Decrease) in Temporary Equity [Roll Forward]	'	'	'
Beginning balance	18,000	17,997	17,989
Cashless exercise of warrants	0	0	'
Accretion of issuance costs on Preferred Stock	'	3	8
Conversion of Preferred Stock into common stock	-18,000	'	'
Ending balance	0	18,000	17,997
Redeemable Convertible Series B-1 Preferred Stock [Member]	'	'	'
Increase (Decrease) in Temporary Equity [Roll Forward]	'	'	'
Beginning balance	3,000	2,999	2,998
Cashless exercise of warrants	0	0	'
Accretion of issuance costs on Preferred Stock	'	1	1
Conversion of Preferred Stock into common stock	-3,000	'	'
Ending balance	0	3,000	2,999
Redeemable Convertible Series C Preferred Stock [Member]	'	'	'
Increase (Decrease) in Temporary Equity [Roll Forward]	'	'	'
Beginning balance	50,608	50,601	50,571
Cashless exercise of warrants	489	0	'
Accretion of issuance costs on Preferred Stock	'	7	30
Conversion of Preferred Stock into common stock	-51,097	'	'
Ending balance	$0	$50,608	$50,601

Stockholders_Equity_Deficit_an4

Stockholders' Equity (Deficit) and Redeemable Convertible Preferred Stock - Additional Information (Details) (USD $)	0 Months Ended				0 Months Ended
	29-May-13	Dec. 31, 2013	Dec. 31, 2012	Dec. 31, 2012	29-May-13	Dec. 31, 2012	29-May-13	Dec. 31, 2008	29-May-13
				Redeemable Convertible Series A Preferred Stock [Member]	Redeemable Convertible Series C Preferred Stock [Member]	Redeemable Convertible Series C Preferred Stock [Member]	Redeemable Convertible Preferred Stock [Member]	Common Stock [Member]	Common Stock [Member]
							Series C Warrants [Member]		Series C Warrants [Member]
Class of Stock [Line Items]	'	'	'	'	'	'	'	'	'
Warrants to purchase stock	'	'	'	175,000	'	4,586,121	206,038	1,616,113	216,491
Conversion of redeemable convertible preferred stock to common stock, shares	13,401,499	'	'	'	12,874	'	'	'	'
Preferred stock, shares authorized	5,000,000	5,000,000	0	'	'	'	'	'	'
Common stock, shares authorized	100,000,000	100,000,000	303,500,000	'	'	'	'	'	'
Preferred stock, par value	'	$0.00	$0	'	'	'	'	'	'
Common stock, par value	'	$0.00	$0.00	'	'	'	'	'	'

Warrants_Additional_Informatio

Warrants - Additional Information (Detail) (USD $)

0 Months Ended

12 Months Ended

1 Months Ended

0 Months Ended

1 Months Ended

12 Months Ended

1 Months Ended

0 Months Ended

1 Months Ended

In Thousands, except Share data, unless otherwise specified

29-May-13

Dec. 31, 2013

Dec. 31, 2012

Dec. 31, 2011

Dec. 31, 2013

Dec. 31, 2012

Dec. 31, 2011

Dec. 31, 2013

Dec. 31, 2012

Dec. 31, 2011

31-May-13

29-May-13

Nov. 07, 2013

Dec. 31, 2013

Nov. 30, 2013

Sep. 30, 2013

Jun. 30, 2013

Dec. 31, 2008

29-May-13

Dec. 31, 2007

Dec. 31, 2008

31-May-13

Dec. 31, 2012

29-May-13

31-May-13

Dec. 31, 2012

Series A Warrants [Member]

Series A Warrants [Member]

Series A Warrants [Member]

Series C Warrants [Member]

Series C Warrants [Member]

Series C Warrants [Member]

Redeemable Convertible Series A and Series C Preferred Stock [Member]

Redeemable Convertible Preferred Stock [Member]

Common Stock [Member]

Common Stock [Member]

Common Stock [Member]

Common Stock [Member]

Common Stock [Member]

Common Stock [Member]

Common Stock [Member]

Common Stock [Member]

Common Stock [Member]

Redeemable Convertible Series A Preferred Stock [Member]

Redeemable Convertible Series A Preferred Stock [Member]

Redeemable Convertible Series C Preferred Stock [Member]

Redeemable Convertible Series C Preferred Stock [Member]

Redeemable Convertible Series C Preferred Stock [Member]

Series C Warrants [Member]

Series C Warrants [Member]

Warrants Expire in 2014 [Member]

Warrants Expire in 2015 [Member]

Class of Warrant or Right [Line Items]

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

Warrants to purchase stock

'

'

'

'

'

'

'

'

'

'

'

206,038

'

'

'

'

'

1,616,113

216,491

958,019

658,094

'

175,000

'

'

4,586,121

Warrants and Rights Outstanding

'

$0

$3,235

'

'

$88

[1]

'

'

$3,147

[1]

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

Fair value adjustment of warrants

'

1,052

5

261

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

Conversion of preferred stock to common stock

13,401,499

'

'

'

'

'

'

'

'

'

13,433

'

'

'

'

'

'

'

'

'

'

'

'

12,874

'

'

Reclassification of warrant liability to equity

$3,632

$3,632

$0

$0

$0

$0

$0

$3,632

$0

$0

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

Cashless exercise of warrant into redeemable convertible preferred stock

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

144,631

'

'

70,320

'

Warrants exercise price

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

16

10.96

'

'

'

'

'

Warrants expiration period

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'2014

'2015

'

'

'

'

'

Exercise of common stock warrants

'

'

'

'

'

'

'

'

'

'

'

'

317,011

88,639

55,316

6,511

194,885

'

'

'

'

'

'

'

'

'

[1]

In order to determine the fair value of the redeemable convertible preferred stock warrants, the Company used a hybrid of the probability-weighted expected return method (bPWERMb) and the option pricing model ("OPM"), collectively referred to as the bHybrid Method,b for the year ended DecemberB 31, 2012. The Hybrid Method is a PWERM model in which one of the valuation scenarios is modeled using an OPM. Significant inputs for the OPM included an estimate of the fair value of the SeriesB A and SeriesB C redeemable convertible preferred stock, the remaining contractual life of the warrants, an estimate of the timing of a liquidity event, a risk-free rate of interest and an estimate of the Companybs stock volatility using the volatilities of guideline peer companies. Significant inputs for the PWERM included an estimate of the Companybs equity value, a weighted average cost of capital and an estimated probability and timing for each valuation scenario.

Equity_Incentive_Plans_and_Sto2

Equity Incentive Plans and Stock-Based Compensation - Additional Information (Detail) (USD $)	12 Months Ended			1 Months Ended				0 Months Ended	12 Months Ended
In Millions, except Share data, unless otherwise specified	Dec. 31, 2013	Dec. 31, 2012	Dec. 31, 2011	31-May-13	Dec. 31, 2013	Dec. 31, 2013	Dec. 31, 2012	Jan. 02, 2014	Dec. 31, 2013
				2013 Plan [Member]	2013 Plan [Member]	2001 Plan [Member]	2001 Plan [Member]	Subsequent Event [Member]	Stock Options [Member]
								2013 Plan [Member]	2001 Plan [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]	'	'	'	'	'	'	'	'	'
Number of shares reserved for issuance	'	'	'	1,250,000	'	'	'	'	'
Description of increase in common stock reserved for issuance	'	'	'	'The number of shares of common stock reserved for issuance under the 2013 Plan will automatically increase on JanuaryB 1 each year, for a period of ten years, from JanuaryB 1, 2014 through JanuaryB 1, 2023, by 5% of the total number of shares of the Companybs common stock outstanding on DecemberB 31 of the preceding calendar year, or a lesser number of shares as may be determined by the Companybs board of directors.	'	'	'	'	'
Common stock reserved for issuance increase, automatic increase, term	'	'	'	'10 years	'	'	'	'	'
Number of shares reserved for issuance, automatic increase, start-date	'	'	'	1-Jan-14	'	'	'	'	'
Number of shares reserved for issuance, automatic increase, end-date	'	'	'	1-Jan-23	'	'	'	'	'
Number of shares reserved for issuance, automatic increase, percent of common stock outstanding of preceding calendar year	'	'	'	5.00%	'	'	'	'	'
Number of additional shares authorized	'	'	'	'	'	'	'	1,182,194	'
Number of shares available for future grant	'	'	'	'	1,104,951	'	'	'	'
Stock options expiration period	'	'	'	'	'	'	'	'	'10 years
Shares of common stock subject to repurchase	'	'	'	'	'	0	0	'	'
Weighted average grant date fair value	$5.29	$2.88	$0.80	'	'	'	'	'	'
Total fair value of stock options vested during period	$0.90	$0.40	$0.20	'	'	'	'	'	'
Aggregate unrecognized stock-based compensation cost	2.2	'	'	'	'	'	'	'	'
Unrecognized compensation cost related to nonvested awards, Weighted-average period recognized	'1 year 10 months 24 days	'	'	'	'	'	'	'	'
Aggregate intrinsic value of stock options exercised	$17.60	$0.70	$0.10	'	'	'	'	'	'

Equity_Incentive_Plans_and_Sto3

Equity Incentive Plans and Stock-Based Compensation - Summary of Stock-Based Compensation Expense (Detail) (USD $)	12 Months Ended
In Thousands, unless otherwise specified	Dec. 31, 2013	Dec. 31, 2012	Dec. 31, 2011
Stock-Based Compensation [Line Items]	'	'	'
Stock-based compensation expense	$2,099	$638	$200
Cost of Revenue [Member]	'	'	'
Stock-Based Compensation [Line Items]	'	'	'
Stock-based compensation expense	204	64	15
Sales and Marketing [Member]	'	'	'
Stock-Based Compensation [Line Items]	'	'	'
Stock-based compensation expense	607	224	16
Research and Development [Member]	'	'	'
Stock-Based Compensation [Line Items]	'	'	'
Stock-based compensation expense	348	105	58
General and Administrative [Member]	'	'	'
Stock-Based Compensation [Line Items]	'	'	'
Stock-based compensation expense	$940	$245	$111

Equity_Incentive_Plans_and_Sto4

Equity Incentive Plans and Stock-Based Compensation - Summary of Weighted-Average Assumptions Used for Estimating Fair Value of Stock Granted (Detail) (Stock Options [Member])	12 Months Ended
	Dec. 31, 2013	Dec. 31, 2012	Dec. 31, 2011
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]	'	'	'
Expected term (years)	'	'	'6 years 3 months
Dividend yield	0.00%	0.00%	0.00%
Minimum [Member]	'	'	'
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]	'	'	'
Risk-free interest rate	0.30%	0.10%	0.40%
Expected term (years)	'5 years	'4 years	'
Expected volatility	43.00%	49.00%	28.00%
Maximum [Member]	'	'	'
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]	'	'	'
Risk-free interest rate	1.70%	0.90%	2.00%
Expected term (years)	'6 years 3 months	'6 years 3 months	'
Expected volatility	59.00%	60.00%	56.00%

Equity_Incentive_Plans_and_Sto5

Equity Incentive Plans and Stock-Based Compensation - Summary of Stock Option Activity (Detail) (USD $)	12 Months Ended
In Thousands, except Share data, unless otherwise specified	Dec. 31, 2013
Number of Options	'
Number of Options, Beginning balance	2,202,712
Number of Options, Granted	722,625
Number of Options, Exercised	-727,318
Number of Options, Forfeited	-104,042
Number of Options, Expired	-25,336
Number of Options, Ending balance	2,068,641
Number of Options, Exercisable	938,151
Number of Options, Vested and expected to vest	1,813,530
Weighted Average Exercise Price	'
Weighted Average Exercise Price, Beginning balance	$3.84
Weighted Average Exercise Price, Granted	$12.74
Weighted Average Exercise Price, Exercised	$3.36
Weighted Average Exercise Price, Forfeited	$8.30
Weighted Average Exercise Price, Expired	$2.67
Weighted Average Exercise Price, Ending balance	$6.95
Weighted Average Exercise Price, Exercisable	$3.30
Weighted Average Exercise Price, Vested and expected to vest	$6.62
Weighted Average Remaining Contractual Term, Outstanding	'7 years 9 months 18 days
Weighted Average Remaining Contractual Term, Exercisable	'6 years 7 months 6 days
Weighted Average Remaining Contractual Term, Vested and expected to vest	'7 years 8 months 5 days
Aggregate Intrinsic Value, Ending balance	$71,914
Aggregate Intrinsic Value, Exercisable	36,039
Aggregate Intrinsic Value, Vested and expected to vest	$63,636

Net_Loss_Per_Share_Schedule_of

Net Loss Per Share - Schedule of Securities Excluded from Calculation of Weighted Average Common Shares Outstanding (Detail)	12 Months Ended
	Dec. 31, 2013	Dec. 31, 2012	Dec. 31, 2011
Redeemable Convertible Series A Preferred Stock [Member]	'	'	'
Antidilutive Securities Excluded from Computation of Earnings Per Share [Line Items]	'	'	'
Antidilutive securities excluded from calculation of weighted average common shares outstanding	0	5,863,825	5,857,864
Redeemable Convertible Series B Preferred Stock [Member]	'	'	'
Antidilutive Securities Excluded from Computation of Earnings Per Share [Line Items]	'	'	'
Antidilutive securities excluded from calculation of weighted average common shares outstanding	0	2,540,066	2,540,066
Redeemable Convertible Series B-1 Preferred Stock [Member]	'	'	'
Antidilutive Securities Excluded from Computation of Earnings Per Share [Line Items]	'	'	'
Antidilutive securities excluded from calculation of weighted average common shares outstanding	0	353,767	353,767
Redeemable Convertible Series C Preferred Stock [Member]	'	'	'
Antidilutive Securities Excluded from Computation of Earnings Per Share [Line Items]	'	'	'
Antidilutive securities excluded from calculation of weighted average common shares outstanding	0	4,617,513	4,617,513
Warrants to Purchase Common Stock [Member]	'	'	'
Antidilutive Securities Excluded from Computation of Earnings Per Share [Line Items]	'	'	'
Antidilutive securities excluded from calculation of weighted average common shares outstanding	986,784	1,616,113	1,616,113
Warrants to Purchase Series A Redeemable Convertible Preferred Stock [Member]	'	'	'
Antidilutive Securities Excluded from Computation of Earnings Per Share [Line Items]	'	'	'
Antidilutive securities excluded from calculation of weighted average common shares outstanding	0	10,937	21,484
Warrants to Purchase Series C Redeemable Convertible Preferred Stock [Member]	'	'	'
Antidilutive Securities Excluded from Computation of Earnings Per Share [Line Items]	'	'	'
Antidilutive securities excluded from calculation of weighted average common shares outstanding	0	286,625	89,750
Stock Options [Member]	'	'	'
Antidilutive Securities Excluded from Computation of Earnings Per Share [Line Items]	'	'	'
Antidilutive securities excluded from calculation of weighted average common shares outstanding	2,068,641	2,202,712	1,936,191

Segment_and_Geographic_Informa2

Segment and Geographic Information - Additional Information (Detail)	12 Months Ended
	Dec. 31, 2013
	segment
Segment Reporting [Abstract]	'
Number of reportable segments	1
Number of operating segment	1

Segment_and_Geographic_Informa3

Segment and Geographic Information - Summary of Revenue by Geography (Detail) (USD $)	3 Months Ended								12 Months Ended
In Thousands, unless otherwise specified	Dec. 31, 2013	Sep. 30, 2013	Jun. 30, 2013	Mar. 31, 2013	Dec. 31, 2012	Sep. 30, 2012	Jun. 30, 2012	Mar. 31, 2012	Dec. 31, 2013	Dec. 31, 2012	Dec. 31, 2011
Segment Reporting Information [Line Items]	'	'	'	'	'	'	'	'	'	'	'
Revenue	$20,486	$16,620	$15,976	$14,922	$15,993	$13,020	$12,408	$12,166	$68,004	$53,587	$43,570
Domestic [Member]	'	'	'	'	'	'	'	'	'	'	'
Segment Reporting Information [Line Items]	'	'	'	'	'	'	'	'	'	'	'
Revenue	'	'	'	'	'	'	'	'	53,832	42,140	34,805
International [Member]	'	'	'	'	'	'	'	'	'	'	'
Segment Reporting Information [Line Items]	'	'	'	'	'	'	'	'	'	'	'
Revenue	'	'	'	'	'	'	'	'	$14,172	$11,447	$8,765

Retirement_Plan_Details

Retirement Plan (Details) (USD $)	12 Months Ended
In Millions, unless otherwise specified	Dec. 31, 2013	Dec. 31, 2012	Dec. 31, 2011
Schedule of Defined Contribution Plans [Line Items]	'	'	'
Maximum employee contribution to defined contribution plan, percent of compensation	100.00%	'	'
Matching contributions, percent of employee contributions	50.00%	'	'
Employer contributions	$0.30	$0.30	$0.20
Maximum [Member]	'	'	'
Schedule of Defined Contribution Plans [Line Items]	'	'	'
Maximum matching contribution, percent of base salary	3.00%	'	'

Selected_Quarterly_Information2

Selected Quarterly Information (unaudited) (Details) (USD $)	3 Months Ended								12 Months Ended
In Thousands, except Per Share data, unless otherwise specified	Dec. 31, 2013	Sep. 30, 2013	Jun. 30, 2013	Mar. 31, 2013	Dec. 31, 2012	Sep. 30, 2012	Jun. 30, 2012	Mar. 31, 2012	Dec. 31, 2013	Dec. 31, 2012	Dec. 31, 2011
Quarterly Financial Information Disclosure [Abstract]	'	'	'	'	'	'	'	'	'	'	'
Revenue	$20,486	$16,620	$15,976	$14,922	$15,993	$13,020	$12,408	$12,166	$68,004	$53,587	$43,570
Gross Profit	15,369	12,065	11,507	10,975	11,951	9,189	8,778	8,920	49,916	38,838	31,322
(Loss) income from operations	-4,991	-3,741	-3,496	-2,137	824	-1,517	-2,347	-809	-14,365	-3,849	-3,177
Net (loss) income	($8,609)	($4,292)	($4,997)	($2,730)	$626	($1,958)	($2,750)	($851)	($20,628)	($4,933)	($3,864)
Net (loss) income per share:	'	'	'	'	'	'	'	'	'	'	'
Basic and diluted (in dollars per share)	($0.38)	($0.20)	($0.56)	($2.10)	$0.04	($1.68)	($2.39)	($0.74)	($1.51)	($4.23)	($3.45)

Subsequent_Events_Additional_I

Subsequent Events - Additional Information (Detail)	Dec. 31, 2013	Jan. 03, 2014	Jan. 03, 2014	Jan. 03, 2014	Jan. 03, 2014	Nov. 07, 2013	Dec. 31, 2013	Nov. 30, 2013	Sep. 30, 2013	Jun. 30, 2013	Jan. 31, 2014
In Thousands, except Share data, unless otherwise specified	USD ($)	Ten-year lease [Member]	Ten-year lease [Member]	Five-year lease [Member]	Five-year lease [Member]	Common Stock [Member]	Common Stock [Member]	Common Stock [Member]	Common Stock [Member]	Common Stock [Member]	Common Stock [Member]
		London, England [Member]	London, England [Member]	London, England [Member]	London, England [Member]						Subsequent Event [Member]
		Subsequent Event [Member]	Subsequent Event [Member]	Subsequent Event [Member]	Subsequent Event [Member]
		USD ($)	GBP (£)	USD ($)	GBP (£)
Subsequent Event [Line Items]	'	'	'	'	'	'	'	'	'	'	'
Exercise of common stock warrants, shares	'	'	'	'	'	317,011	88,639	55,316	6,511	194,885	664,058
Term of contract	'	'10 years	'10 years	'5 years	'5 years	'	'	'	'	'	'
Break option term	'	'5 years	'5 years	'	'	'	'	'	'	'	'
Future minimum lease payments	$15,317	$15,500	£ 9,400	$7,300	£ 4,400	'	'	'	'	'	'