ChannelAdvisor (ECOM) 10-K 11 Feb 21 2020 FY Annual report Financial data

Cover

Cover - USD ($)	12 Months Ended
	Dec. 31, 2020	Feb. 01, 2021	Jun. 30, 2020
Cover [Abstract]
Document Type	10-K
Document Annual Report	true
Document Period End Date	Dec. 31, 2020
Current Fiscal Year End Date	--12-31
Document Transition Report	false
Entity File Number	001-35940
Entity Registrant Name	CHANNELADVISOR CORPORATION
Entity Incorporation, State or Country Code	DE
Entity Tax Identification Number	56-2257867
Entity Address, Address Line One	3025 Carrington Mill Boulevard
Entity Address, City or Town	Morrisville
Entity Address, State or Province	NC
Entity Address, Postal Zip Code	27560
City Area Code	919
Local Phone Number	228-4700
Title of 12(b) Security	Common Stock, $0.001 par value
Trading Symbol	ECOM
Security Exchange Name	NYSE
Entity Well-known Seasoned Issuer	No
Entity Voluntary Filers	No
Entity Current Reporting Status	Yes
Entity Interactive Data Current	Yes
Entity Filer Category	Accelerated Filer
Entity Small Business	false
Entity Emerging Growth Company	false
ICFR Auditor Attestation Flag	true
Entity Shell Company	false
Entity Public Float			$ 433,184,052
Entity Common Stock, Shares Outstanding (in shares)		29,047,290
Documents Incorporated by Reference	DOCUMENTS INCORPORATED BY REFERENCE Portions of the Company's definitive proxy statement, to be filed pursuant to Regulation 14A under the Securities Exchange Act of 1934, for its 2021 Annual Meeting of Stockholders are incorporated by reference in Part III of this Form 10-K.
Amendment Flag	false
Document Fiscal Year Focus	2020
Document Fiscal Period Focus	FY
Entity Central Index Key	0001169652

CONSOLIDATED BALANCE SHEETS

CONSOLIDATED BALANCE SHEETS - USD ($) $ in Thousands	Dec. 31, 2020	Dec. 31, 2019
Current assets:
Cash and cash equivalents	$ 71,545	$ 51,785
Accounts receivable, net of allowance of $417 and $733 as of December 31, 2020 and 2019, respectively	24,705	22,126
Prepaid expenses and other current assets	13,874	10,452
Total current assets	110,124	84,363
Operating lease right of use assets	8,141	11,128
Property and equipment, net	8,707	9,597
Goodwill	30,990	23,486
Intangible assets, net	4,155	1,285
Deferred contract costs, net of current portion	14,040	12,810
Long-term deferred tax assets, net	3,551	3,584
Other assets	953	614
Total assets	180,661	146,867
Current liabilities:
Accounts payable	158	409
Accrued expenses	14,008	8,577
Deferred revenue	22,819	21,000
Other current liabilities	6,029	6,431
Total current liabilities	43,014	36,417
Long-term operating leases, net of current portion	5,394	9,767
Long-term finance leases, net of current portion	8	27
Other long-term liabilities	2,154	1,007
Total liabilities	50,570	47,218
Commitments and contingencies (Note 6)
Stockholders' equity:
Preferred stock, $0.001 par value, 5,000,000 shares authorized, no shares issued and outstanding as of December 31, 2020 and 2019, respectively	0	0
Common stock, $0.001 par value, 100,000,000 shares authorized, 29,020,424 and 28,077,469 shares issued and outstanding as of December 31, 2020 and 2019, respectively	29	28
Additional paid-in capital	288,842	278,111
Accumulated other comprehensive loss	(1,095)	(1,740)
Accumulated deficit	(157,685)	(176,750)
Total stockholders' equity	130,091	99,649
Total liabilities and stockholders' equity	$ 180,661	$ 146,867
Common stock, shares issued (in shares)	29,020,424	28,077,469
Common stock, shares outstanding (in shares)	29,020,424	28,077,469

CONSOLIDATED BALANCE SHEETS (Pa

CONSOLIDATED BALANCE SHEETS (Parenthetical) - USD ($) $ in Thousands	Dec. 31, 2020	Dec. 31, 2019
Current assets:
Allowance for doubtful accounts receivable, current	$ 417	$ 733
Stockholders' equity:
Preferred stock, par value (in dollars per share)	$ 0.001	$ 0.001
Preferred stock, shares authorized (in shares)	5,000,000	5,000,000
Preferred stock, shares issued (in shares)	0	0
Preferred stock, shares outstanding (in shares)	0	0
Common stock, par value (in dollars per share)	$ 0.001	$ 0.001
Common stock, shares authorized (in shares)	100,000,000	100,000,000
Common stock, shares issued (in shares)	29,020,424	28,077,469
Common stock, shares outstanding (in shares)	29,020,424	28,077,469

CONSOLIDATED STATEMENTS OF OPER

CONSOLIDATED STATEMENTS OF OPERATIONS - USD ($)	12 Months Ended
	Dec. 31, 2020	Dec. 31, 2019	Dec. 31, 2018
Income Statement [Abstract]
Revenue	$ 145,072,000	$ 129,959,000	$ 131,218,000
Cost of revenue	30,354,000	29,008,000	29,501,000
Gross profit	114,718,000	100,951,000	101,717,000
Operating expenses:
Sales and marketing	52,905,000	52,813,000	60,080,000
Research and development	18,990,000	19,200,000	22,359,000
General and administrative	23,739,000	25,136,000	26,784,000
Total operating expenses	95,634,000	97,149,000	109,223,000
Income (loss) from operations	19,084,000	3,802,000	(7,506,000)
Other income (expense):
Interest income (expense), net	175,000	754,000	510,000
Other income (expense), net	9,000	(385,000)	9,000
Total other income (expense)	184,000	369,000	519,000
Income (loss) before income taxes	19,268,000	4,171,000	(6,987,000)
Income tax expense	443,000	689,000	614,000
Net income (loss)	$ 18,825,000	$ 3,482,000	$ (7,601,000)
Net income (loss) per share:
Basic (in dollars per share)	$ 0.66	$ 0.12	$ (0.28)
Diluted (in dollars per share)	$ 0.63	$ 0.12	$ (0.28)
Weighted average common shares outstanding:
Weighted average common shares outstanding, basic	28,616,401	27,886,278	27,138,274
Weighted average common shares outstanding, diluted	30,035,261	28,816,977	27,138,274

CONSOLIDATED STATEMENTS OF COMP

CONSOLIDATED STATEMENTS OF COMPREHENSIVE LOSS - USD ($)	12 Months Ended
	Dec. 31, 2020	Dec. 31, 2019	Dec. 31, 2018
Statement of Comprehensive Income [Abstract]
Net income (loss)	$ 18,825,000	$ 3,482,000	$ (7,601,000)
Other comprehensive (loss) income:
Foreign currency translation adjustments	645,000	(33,000)	(918,000)
Total comprehensive income (loss)	$ 19,470,000	$ 3,449,000	$ (8,519,000)

CONSOLIDATED STATEMENTS OF CHAN

CONSOLIDATED STATEMENTS OF CHANGES IN STOCKHOLDERS' EQUITY - USD ($)	Total	Common Stock	Additional Paid-In Capital	Accumulated Other Comprehensive Loss	Accumulated Deficit
Beginning balance (in shares) at Dec. 31, 2017		26,601,626
Beginning balance, amount at Dec. 31, 2017	$ 81,911,000	$ 27,000	$ 262,805,000	$ (789,000)	$ (180,132,000)
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Exercise of stock options and vesting of restricted stock units (in shares)		1,034,146
Exercise of stock options and vesting of restricted stock units	1,106,000	$ 0	1,106,000
Stock-based compensation expense	10,598,000		10,598,000
Statutory tax withholding related to net-share settlement of restricted stock units (in shares)		(288,657)
Statutory tax withholding related to net-share settlement of restricted stock units	(2,959,000)		(2,959,000)
Net income (loss)	(7,601,000)				(7,601,000)
Foreign currency translation adjustments	(918,000)			(918,000)
Ending balance (in shares) at Dec. 31, 2018		27,347,115
Ending balance, amount at Dec. 31, 2018	89,638,000	$ 27,000	271,550,000	(1,707,000)	(180,232,000)
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Exercise of stock options and vesting of restricted stock units (in shares)		1,021,730
Exercise of stock options and vesting of restricted stock units	975,000	$ 1,000	974,000
Stock-based compensation expense	8,976,000		8,976,000
Statutory tax withholding related to net-share settlement of restricted stock units (in shares)		(291,376)
Statutory tax withholding related to net-share settlement of restricted stock units	(3,389,000)		(3,389,000)
Net income (loss)	3,482,000				3,482,000
Foreign currency translation adjustments	(33,000)			(33,000)
Ending balance (in shares) at Dec. 31, 2019		28,077,469
Ending balance, amount at Dec. 31, 2019	99,649,000	$ 28,000	278,111,000	(1,740,000)	(176,750,000)
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Exercise of stock options and vesting of restricted stock units (in shares)		1,183,904
Exercise of stock options and vesting of restricted stock units	3,826,000	$ 1,000	3,825,000
Stock-based compensation expense	10,200,000		10,200,000
Statutory tax withholding related to net-share settlement of restricted stock units (in shares)		(240,949)
Statutory tax withholding related to net-share settlement of restricted stock units	(3,294,000)		(3,294,000)
Net income (loss)	18,825,000				18,825,000
Foreign currency translation adjustments	645,000			645,000
Ending balance (in shares) at Dec. 31, 2020		29,020,424
Ending balance, amount at Dec. 31, 2020	$ 130,091,000	$ 29,000	$ 288,842,000	$ (1,095,000)	$ (157,685,000)

CONSOLIDATED STATEMENTS OF CASH

CONSOLIDATED STATEMENTS OF CASH FLOWS - USD ($)	12 Months Ended
	Dec. 31, 2020	Dec. 31, 2019	Dec. 31, 2018
Cash flows from operating activities
Net income (loss)	$ 18,825,000	$ 3,482,000	$ (7,601,000)
Adjustments to reconcile net income (loss) to cash and cash equivalents provided by operating activities:
Depreciation and amortization	6,513,000	6,336,000	6,094,000
Bad debt expense	525,000	1,147,000	991,000
Stock-based compensation expense	10,200,000	8,976,000	10,598,000
Deferred income taxes	(39,000)	531,000	493,000
Other items, net	(829,000)	118,000	(851,000)
Changes in assets and liabilities, net of effects from acquisition:
Accounts receivable	(2,143,000)	361,000	2,634,000
Prepaid expenses and other assets	(1,728,000)	892,000	10,303,000
Deferred contract costs	2,572,000
Deferred contract costs		(3,146,000)	(6,730,000)
Accounts payable and accrued expenses	4,270,000	(2,306,000)	(10,936,000)
Deferred revenue	1,284,000	(3,383,000)	(3,765,000)
Cash and cash equivalents provided by operating activities	34,306,000	13,008,000	1,230,000
Cash flows from investing activities
Acquisition, net of cash acquired	(8,467,000)	0	0
Purchases of property and equipment	(1,704,000)	(986,000)	(2,045,000)
Payment of internal-use software development costs	(3,034,000)	(2,721,000)	(894,000)
Cash and cash equivalents used in investing activities	(13,205,000)	(3,707,000)	(2,939,000)
Cash flows from financing activities
Repayment of finance leases and debt	(1,808,000)	(2,209,000)	(2,241,000)
Proceeds from exercise of stock options	3,825,000	974,000	1,106,000
Payment of statutory tax withholding related to net-share settlement of restricted stock units	(3,294,000)	(3,389,000)	(2,959,000)
Payment of line of credit financing costs	(187,000)	0	0
Cash and cash equivalents used in financing activities	(1,464,000)	(4,624,000)	(4,094,000)
Effect of currency exchange rate changes on cash and cash equivalents	123,000	(77,000)	(434,000)
Net increase (decrease) in cash and cash equivalents	19,760,000	4,600,000	(6,237,000)
Cash and cash equivalents, beginning of period	51,785,000	47,185,000	53,422,000
Cash and cash equivalents, end of period	71,545,000	51,785,000	47,185,000
Supplemental disclosure of cash flow information
Cash paid for interest	160,000	215,000	30,000
Cash paid for income taxes, net	462,000	62,000	113,000
Supplemental disclosure of noncash investing and financing activities
Accrued capital expenditures	32,000	15,000	68,000
Finance lease obligations entered into for the purchase of fixed assets	$ 0	$ 46,000	$ 4,217,000

Description of the Business

Description of the Business	12 Months Ended
	Dec. 31, 2020
Organization, Consolidation and Presentation of Financial Statements [Abstract]
DESCRIPTION OF THE BUSINESS	DESCRIPTION OF THE BUSINESSChannelAdvisor 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, or SaaS, solutions and its mission is to connect and optimize the world's commerce. ChannelAdvisor's SaaS cloud platform helps brands and retailers worldwide improve their online performance by expanding sales channels, connecting with consumers around the world, optimizing their operations for peak performance and providing actionable analytics to improve competitiveness. The Company is headquartered in Morrisville, North Carolina and maintains sales, service, support and research and development offices in various domestic and international locations.

Significant Accounting Policies

Significant Accounting Policies	12 Months Ended
	Dec. 31, 2020
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. Depreciation and Amortization Depreciation and amortization expense is included in the following line items in the accompanying consolidated statements of operations for the years ended December 31, 2020, 2019 and 2018 (in thousands): 2020 2019 2018 Cost of revenue $ 4,211 $ 3,942 $ 3,610 Sales and marketing 624 775 884 Research and development 257 353 371 General and administrative 1,421 1,266 1,229 $ 6,513 $ 6,336 $ 6,094 Recent Accounting Pronouncements Standard Description Effect on the Financial Statements or Other Significant Matters Standards that the Company adopted effective January 1, 2020 Financial Instruments: Accounting Standards Update, or ASU, 2016-13, Financial Instruments - Credit Losses (Topic 326) Effective date: January 1, 2020 The standard replaces the incurred loss impairment methodology in current U.S. GAAP (defined below) with a methodology that reflects expected credit losses. The update is intended to provide financial statement users with more useful information about expected credit losses. The Company adopted this standard effective January 1, 2020. The adoption did not have a material impact on its consolidated financial statements. Intangibles: ASU 2018-15, Intangibles -Goodwill and Other - Internal-Use Software (Subtopic 350-40) Effective date: January 1, 2020 This standard aligns the requirements for capitalizing implementation costs incurred in a hosting arrangement that is a service contract with the requirements for capitalizing implementation costs incurred to develop or obtain internal-use software. The Company adopted this standard effective January 1, 2020. The adoption did not have a material impact on its consolidated financial statements. Income Taxes: ASU 2019-12, Income Taxes (Topic 740) Simplifying the Accounting for Income Taxes Effective date: January 1, 2020 This standard amends the approaches and methodologies in accounting for income taxes during interim periods and makes changes to certain income tax classifications. The new standard allows exceptions to the use of the incremental approach for intra-period tax allocation, when there is a loss from continuing operations and income or a gain from other items, and to the general methodology for calculating income taxes in an interim period, when a year-to-date loss exceeds the anticipated loss for the year. The standard also requires franchise or similar taxes partially based on income to be reported as income tax and the effects of enacted changes in tax laws or rates to be included in the annual effective tax rate computation from the date of enactment. Lastly, the Company would be required to evaluate when the step-up in the tax basis of goodwill is part of the business combination and when it should be considered a separate transaction. ASU 2019-12 is effective for fiscal years, and interim periods within those fiscal years, beginning after December 15, 2020. The Company early adopted this standard effective January 1, 2020. The early adoption did not have a material impact on its consolidated financial statements or related disclosures. The Company has reviewed other new accounting pronouncements that were issued as of December 31, 2020 and does not believe that these pronouncements are applicable to the Company, or that they will have a material impact on its financial position or results of operations. The Securities and Exchange Commission, or SEC, issued a final rule on November 19, 2020, adopting amendments to Regulation S-K to modernize, simplify and enhance certain disclosure requirements. The amendments reflect a principles-based, registrant-specific approach to disclosure intended to enhance the focus of financial disclosures on material information for the benefit of investors, while simplifying compliance efforts for registrants. Registrants are required to comply with the rule beginning with the first fiscal year ending on or after August 9, 2021, or the mandatory compliance date. Although registrants are not required to apply the amended rules until the mandatory compliance date, they may comply with the final amendments any time after the effective date, so long as disclosure responsive to an amended item is provided in its entirety. The Company early adopted these amendments, effective for this Annual Report. Use of Estimates The preparation of financial statements in conformity with United States generally accepted accounting principles, or 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, income taxes, assumptions used for purposes of determining stock-based compensation, leases, including estimating lease terms and extensions, and revenue recognition, including standalone selling prices for contracts with multiple performance obligations and the expected period of benefit for deferred contract costs, among others. Estimates and assumptions are also required to value assets acquired and liabilities assumed as well as contingent consideration, where applicable, in conjunction with business combinations. 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 with an original maturity of 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. Revenue Recognition Revenue is recognized when a customer obtains control of promised services, in an amount that reflects the consideration the Company expects to be entitled to receive in exchange for those services. In determining the amount of revenue to be recognized, the Company performs the following steps: (i) identification of the contract with a customer; (ii) identification of the promised services in the contract and determination of whether the promised services are performance obligations, including whether they are distinct in the context of the contract; (iii) determination of the transaction price; (iv) allocation of the transaction price to the performance obligations based on estimated selling prices; and (v) recognition of revenue when (or as) the Company satisfies each performance obligation. Refer to Note 8, "Revenue from Contracts with Customers" for a detailed discussion of accounting policies related to revenue recognition, including deferred revenue and sales commissions. Cost of Revenue Cost of revenue primarily consists of personnel and related costs, including salaries, bonuses, payroll taxes and stock-based compensation, co-location facility costs for the Company's data centers, depreciation expense for computer equipment and amortization of capitalized software 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 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. 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. The acquisition of Blueboard, a private limited company organized under the laws of France ("BlueBoard") on July 23, 2020 includes a contingent consideration arrangement, as described in Note 4 below. Contingent consideration was measured at fair value at the acquisition date and is remeasured at fair value at each reporting date until the contingency is resolved. The fair value of the contingent consideration related to the BlueBoard acquisition was estimated utilizing Black-Scholes option pricing models in which various scenarios for achievement of the financial targets and resulting payouts are then discounted to determine the present value of the resulting liability. Key assumptions used in the measurement of fair value of contingent consideration include the forecasted revenue growth, revenue volatility and discount rates among other assumptions. Changes in any valuation inputs in isolation may result in a significantly lower or higher fair value measurement in the future. Subsequent changes in the fair value of contingent consideration are recognized within general and administrative expenses in the Company’s consolidated statements of operations. As of December 31, 2020, the fair value of the contingent consideration was $1.3 million, of which $0.6 million is recorded in "Other current liabilities" and $0.7 million is recorded in "Other long-term liabilities." The following table presents the changes to the Company's liability for acquisition-related contingent consideration for the year ended December 31, 2020 (in thousands): Balance as of December 31, 2019 $ — Acquisition 1,516 Change in fair value (186) Balance as of December 31, 2020 $ 1,330 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 equivalents accounts exceed federally insured limits. The Company has not experienced any losses on its cash and cash equivalents accounts to date. To manage accounts receivable risk, the Company maintains an allowance for credit losses. The Company did not have any customers that individually comprised a significant concentration of its accounts receivable as of December 31, 2020 and 2019, or a significant concentration of its revenue for the years ended December 31, 2020, 2019 and 2018. Accounts Receivable and Allowance for Credit Losses The Company extends credit to customers without requiring collateral. Accounts receivable are stated at amortized cost, net of an allowance for credit losses. The Company records an allowance for credit losses at the time that accounts receivable are initially recorded based on its consideration of the current economic environment, expectations of future economic conditions, the Company's historical collection experience and a loss-rate approach whereby impairment is calculated by multiplying an estimated loss rate by the asset's amortized cost at the balance sheet date. The Company reassesses the allowance at each reporting date. When it becomes apparent, based on age or customer circumstances, that such amounts will not be collected, they are charged to the allowance. Payments subsequently received are credited to the credit loss expense account included within general and administrative expense in the consolidated statements of operations. The following table presents the changes in the Company's allowance for credit losses during the year ended December 31, 2020 (in thousands): Balance, Provision for credit losses (1) Write-offs, net of recoveries Balance, Allowance for credit losses: Year ended December 31, 2020 $ 733 525 (841) $ 417 (1) Includes adjustment recorded at January 1, 2020 as a result of the Company's adoption of Accounting Standards Update No. 2016-13, Financial Instruments - Credit Losses (Topic 326). 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 capitalized software development costs 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. 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. Capitalized software development costs related to creating internally developed software and implementing software purchased for internal use are included in property and equipment in the accompanying consolidated balance sheets. The Company capitalized software development costs of $3.1 million and $3.0 million during the years ended December 31, 2020 and 2019, respectively. Amortization expense related to capitalized internally developed software was $1.8 million, $0.8 million and $0.3 million for the years ended December 31, 2020, 2019 and 2018, respectively, and is included in cost of revenue or general and administrative expense in the accompanying consolidated statements of operations, depending upon the nature of the software development project. The net book value of capitalized internally developed software was $4.2 million and $2.9 million at December 31, 2020 and 2019, respectively. 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 and amortization methodology used in computing amortization are as follows: Estimated Useful Lives Amortization Methodology Customer relationships 7 years Straight-line Acquired technology 7 years Straight-line Impairment of Long-Lived Assets The Company reviews long-lived 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, 2020 and 2019, 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. The Company recorded goodwill in connection with its business acquisitions. Refer to Note 4 below for information regarding goodwill recorded in connection with the acquisition of BlueBoard. Goodwill is not amortized, but is subject to an annual impairment test, as described below. The Company has determined that it has a single, entity-wide reporting unit. The Company first assessed qualitative factors to determine whether it was more likely than not that the fair value of its single reporting unit was less than its carrying amount as a basis for determining whether it is necessary to perform the two-step goodwill impairment test under ASU No. 2011-08, Goodwill and Other (Topic 350): Testing Goodwill for Impairment. If the qualitative factors had indicated that it was more likely than not that the fair value of the reporting unit was less than its carrying amount, the Company would have tested 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. The Company performs its annual goodwill impairment analysis as of October 1, the first day of the fourth quarter. As a result of the Company's annual impairment analysis as of October 1, 2020 and 2019, 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, 2020, 2019 and 2018 was $3.5 million, $4.2 million and $5.7 million, respectively. 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. As of December 31, 2020, the Company recorded a nominal amount of accrued interest and penalties associated with unrecognized tax positions. As of December 31, 2019, the Company did not have any accrued interest or penalties associated with unrecognized tax positions. The Company's policy for recording interest and penalties is to record them as a component of provision for income taxes. Foreign Currency Translation The functional currency of the Company's non-U.S. operations is the local currency. Monetary assets and liabilities denominated in foreign currencies are translated into U.S. dollars at exchange rates prevailing at the balance sheet dates. Non-monetary assets and liabilities are translated at the historical rates in effect when the assets were acquired or obligations incurred. Revenue and expenses are translated into U.S. dollars using the average rates of exchange prevailing during the period. Translation gains or losses are included as a component of accumulated other comprehensive loss in stockholders' equity. Gains and losses resulting from foreign currency transactions are recognized as other income (expense). Stock-Based Compensation The Company accounts for stock-based compensation awards, which include stock options, time-based restricted stock units, or RSUs, and performance-based vesting restricted stock units, or PSUs, 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 the Company's stock price, as well as highly subjective assumptions, including the expected life of the option and the expected stock price volatility, which is estimated based on the historical volatility of the Company's stock. Additionally, the recognition of expense requires the estimation of the number of awards that will ultimately vest and the number of awards that will ultimately be forfeited. The fair value of the Company's common stock, for purposes of determining the grant date fair value of option, RSU and PSU awards, has been determined by using the closing market price per share of common stock as quoted on the New York Stock Exchange on the date of grant. Basic and Diluted Income (Loss) per Common Share Basic net income (loss) per share is calculated by dividing net income (loss) by the weighted-average number of shares of common stock outstanding for the period. Diluted net income (loss) per share is calculated giving effect to all potentially dilutive shares of common stock, including stock options, RSUs and PSUs. The dilutive effect of outstanding awards is reflected in diluted earnings per share by application of the treasury stock method.

Property and Equipment

Property and Equipment	12 Months Ended
	Dec. 31, 2020
Property, Plant and Equipment [Abstract]
PROPERTY AND EQUIPMENT	PROPERTY AND EQUIPMENT Property and equipment consisted of the following as of December 31, 2020 and 2019 (in thousands): 2020 2019 Purchased software, including capitalized software development costs $ 17,303 $ 13,965 Computer hardware 9,541 8,975 Furniture and office equipment 2,388 2,369 Leasehold improvements 7,368 7,244 Construction in process 48 46 36,648 32,599 Less: accumulated depreciation (27,941) (23,002) Property and equipment, net $ 8,707 $ 9,597 Depreciation expense for the years ended December 31, 2020, 2019 and 2018 was $5.7 million, $5.7 million and $5.5 million, respectively. During the year ended December 31, 2020, the Company disposed of purchased software, including capitalized software development costs, computer hardware, furniture and office equipment with a cost of $0.8 million and

Business Combination, Goodwill

Business Combination, Goodwill and Intangible Assets	12 Months Ended
	Dec. 31, 2020
Goodwill and Intangible Assets Disclosure [Abstract]
GOODWILL AND INTANGIBLE ASSETS	GOODWILL AND INTANGIBLE ASSETS Business Combination On July 23, 2020, the Company entered into a Share Purchase Agreement (the "Purchase Agreement") pursuant to which it acquired all of the issued and outstanding shares of Blueboard, a private limited company organized under the laws of France ("BlueBoard"). BlueBoard is headquartered in Paris, France and is a leader in e-commerce analytics. The acquisition of BlueBoard adds analytic capabilities, including actionable insights into how products are performing across thousands of retailer websites and marketplaces, to the Company's existing cloud-based e-commerce solutions. Under the Purchase Agreement, the Company paid to the shareholders of BlueBoard a cash purchase price of $9.0 million, which is subject to adjustment as set forth in the Purchase Agreement. A portion of the purchase price has been placed into escrow to secure the indemnification obligations of BlueBoard's shareholders until July 22, 2021. In addition to the purchase price paid at the closing, the Company may be obligated to pay up to $3.0 million to the BlueBoard shareholders upon the achievement of specified annual revenue targets through July 2023, as set forth in the Purchase Agreement. Pursuant to ASC Topic 805, Business Combinations , or ASC 805, this contingent consideration is deemed to be part of the purchase price and is recorded as a liability based on the estimated fair value of the consideration the Company expects to pay as of the acquisition date. As of December 31, 2020, $1.3 million of contingent consideration was recorded as a liability on the Company's condensed consolidated balance sheet. The acquisition has been accounted for under the acquisition method of accounting in accordance with ASC 805. Under the acquisition method of accounting, the Company allocated the purchase price to the identifiable assets acquired and liabilities assumed based on their estimated acquisition-date fair values. The fair values of the identifiable intangible assets were determined based on income approaches utilizing forecasted earnings assumptions. The excess of the purchase price over the net assets acquired is recorded as goodwill. Based on management's provisional assessment of the acquisition-date fair value of the assets acquired and liabilities assumed, the aggregate purchase price of $10.5 million, which is comprised of $9.0 million of cash and $1.5 million for contingent consideration noted above, has been allocated to the Company's assets and liabilities on a preliminary basis as follows: $7.5 million to goodwill, $3.7 million to identifiable intangible assets, including acquired technology of $3.3 million and customer relationships of $0.4 million, $0.6 million to long-term deferred tax liabilities and $0.1 million to working capital as a net current liability. The purchase price allocation in conjunction with the acquisition of BlueBoard is subject to change as additional information becomes available. Any adjustments will be made as soon as practicable, but not later than one year from the acquisition date. The goodwill arising from the acquisition of BlueBoard represents the future economic benefits expected to arise from other intangible assets that do not qualify for separate recognition, including acquired workforce, as well as expected future synergies. The goodwill recognized is not deductible for income tax purposes. The Company incurred transaction costs in connection with the acquisition of $0.5 million for the year ended December 31, 2020, which are included in general and administrative expense in the accompanying consolidated statements of operations. Comparative pro forma financial information for this acquisition has not been presented because the acquisition is not material to the Company's consolidated results of operations. Goodwill and Intangible Assets The following table shows the changes in the carrying amount of goodwill for the year ended December 31, 2020 (in thousands): Balance as of December 31, 2019 $ 23,486 Goodwill attributable to the BlueBoard acquisition 7,504 Balance as of December 31, 2020 $ 30,990 There were no changes to the Company's goodwill during the year ended December 31, 2019. Intangible assets consisted of the following as of December 31, 2020 and 2019 (in thousands): December 31, 2020 Gross Carrying Accumulated Net Carrying Weighted Average Customer relationships $ 2,603 $ (1,940) $ 663 7.0 Acquired technology 5,367 (1,875) 3,492 7.0 Total $ 7,970 $ (3,815) $ 4,155 7.0 December 31, 2019 Gross Carrying Accumulated Net Carrying Weighted Average Customer relationships $ 2,230 $ (1,598) $ 632 7.0 Acquired technology 2,030 (1,377) 653 7.0 Total $ 4,260 $ (2,975) $ 1,285 7.0 Amortization expense was $0.8 million for the year ended December 31, 2020 and $0.6 million for each of the years ended December 31, 2019 and 2018. As of December 31, 2020, expected amortization expense over the remaining intangible asset lives is as follows (in thousands): Year Ending December 31, 2021 $ 1,048 2022 596 2023 596 2024 557 2025 530 Thereafter 828 Total $ 4,155

Leases

Leases	12 Months Ended
	Dec. 31, 2020
Leases [Abstract]
Lessee, Finance Leases [Text Block]	LEASES Operating and Finance Lease Commitments The Company leases office facilities and certain equipment under non-cancelable operating and finance leases. The Company determines if an arrangement is a lease and whether its classification is operating or finance at inception. Leases with an initial term of twelve months or less that are not expected to be renewed are not recorded on the balance sheet. For such leases, lease expense for minimum lease payments is recognized on a straight-line basis over the lease term. Certain operating leases include options to renew, with renewal terms extending up to 10 years, subject to certain conditions and notice obligations set forth in the lease agreements. The exercise of lease renewal options is at the Company's discretion. Operating lease right of use, or ROU, assets represent the Company's right to use an underlying asset for the lease term and lease liabilities represent the Company's obligation to make lease payments arising from the lease. Operating lease ROU assets and operating lease liabilities are recognized based on the present value of the future minimum lease payments over the lease term at commencement date. As the Company's leases do not provide an implicit rate, the Company uses its incremental borrowing rate based on the Company's best estimate of the collateralized borrowing rate over a similar term at the commencement date of the lease in determining the present value of future payments. The operating lease ROU assets also include any lease payments made and lease incentives and initial direct costs incurred. The lease terms may include options to extend the lease when it is reasonably certain that the Company will exercise that option. The following table summarizes the Company's lease assets and liabilities as of December 31, 2020 and 2019 (in thousands): December 31, 2020 December 31, 2019 Assets Operating lease right of use assets $ 8,141 $ 11,128 Finance lease assets, included in Property and equipment, net (1) 495 1,917 Total leased assets $ 8,636 $ 13,045 Liabilities Current Operating lease liabilities, included in Other current liabilities $ 4,716 $ 4,177 Finance lease liabilities, included in Other current liabilities 15 1,418 Long-term Long-term operating leases, net of current portion 5,394 9,767 Finance leases, net of current portion $ 8 $ 27 Total lease liabilities $ 10,133 $ 15,389 (1) Finance leases are presented net of accumulated amortization of $5.8 million and $4.4 million as of December 31, 2020 and 2019, respectively. The following table summarizes the components of lease expense for the years ended December 31, 2020 and 2019 (in thousands): 2020 2019 Operating lease cost, included in General and administrative expense (1) $ 4,093 $ 4,808 Finance lease cost: Amortization of leased assets, included in General and administrative expense 1,421 2,041 Interest on lease liabilities, included in Other income (expense), net 35 140 Less: sublease income, reducing rent expense in General and administrative expense (2) (167) (168) Net lease cost $ 5,382 $ 6,821 (1) Excludes short-term lease costs of $0.2 million and $0.4 million for the years ended December 31, 2020 and 2019, respectively. (2) The Company subleases space to a third party for which it anticipates receiving $0.2 million in annual rental payments during the term of the sublease agreement, which is through August 2022. The following table summarizes other information related to leases for the years ended December 31, 2020 and 2019 (in thousands): 2020 2019 Supplemental cash flows information Cash paid for amounts included in the measurement of lease liabilities: Operating cash outflows from operating leases $ 4,501 $ 4,852 Operating cash outflows from finance leases 105 216 Financing cash outflows from finance leases 1,422 2,209 Weighted-average remaining lease term (years) Operating leases 2.22 3.20 Finance leases 0.41 1.37 Weighted-average discount rate Operating leases 5.48 % 5.50 % Finance leases 7.12 % 7.28 % The following table summarizes maturities of lease liabilities as of December 31, 2020 (in thousands): Operating Leases Finance Leases 2021 $ 5,130 $ 15 2022 4,360 8 2023 1,236 — Total lease payments $ 10,726 $ 23 Less: imputed interest (616) — Present value of lease liabilities $ 10,110 $ 23 As of December 31, 2020, the Company had no material operating or finance leases that had not yet commenced.

Commitments and Contingencies

Commitments and Contingencies	12 Months Ended
	Dec. 31, 2020
Commitments and Contingencies Disclosure [Abstract]
COMMITMENTS AND CONTINGENCIES	COMMITMENTS AND CONTINGENCIESFrom time to time, the Company is subject to litigation and claims arising in the ordinary course of business. It is not currently party to any material legal proceedings and it is not aware of any pending or threatened legal proceeding against the Company that it believes could have a material adverse effect on its business, operating results, cash flows or financial condition.

Line of Credit

Line of Credit	12 Months Ended
	Dec. 31, 2020
Debt Disclosure [Abstract]
LINE OF CREDIT	LINE OF CREDITOn August 5, 2020, the Company established a $25.0 million revolving credit facility with a commercial lender that is available for use until August 5, 2023. Proceeds from borrowings under the credit facility may be used for working capital and general corporate purposes, including acquisitions. Up to $10.0 million of the facility is available for letters of credit. Additionally, the Company may request increases to the facility, subject to the consent of the lender, provided that the aggregate amount of such increases during the term do not exceed $10.0 million. Amounts borrowed under the facility will bear interest equal to either a base rate plus 2.25% per annum or LIBOR plus 3.25% per annum. The Company will pay a fee on all outstanding letters of credit at a rate of 3.25% per annum. In addition, the Company will pay a quarterly fee at a rate of 0.50% per annum on the undrawn portion of the facility. As collateral for extension of credit under the facility, the Company granted security interests in substantially all of its assets and those of one of its subsidiaries. The agreement for the credit facility contains customary representations and warranties and subjects the Company to affirmative and negative covenants. As of December 31, 2020, the Company had not drawn on, or issued any letters of credit under, the credit facility.

Revenue from Contracts with Cus

Revenue from Contracts with Customers	12 Months Ended
	Dec. 31, 2020
Revenue from Contract with Customer [Abstract]
REVENUE FROM CONTRACTS WITH CUSTOMERS	REVENUE FROM CONTRACTS WITH CUSTOMERS Revenue Recognition The Company derives the majority of its revenue from subscription fees paid for access to and usage of its SaaS solutions for a specified contract term. A customer typically pays a recurring subscription fee based on a specified minimum amount of gross merchandise value (GMV) or advertising spend that the customer expects to process through the Company's platform. Subscription fees may also include implementation fees such as launch assistance and training fees. The remaining portion of a customer's fee is variable and is based on a specified percentage of GMV or advertising spend processed through the Company's platform in excess of the customer's specified minimum GMV or advertising spend amount. In most cases, the specified percentage of excess GMV or advertising spend on which the variable fee is based is fixed and does not vary depending on the amount of the excess. Subscription fees are billed in advance of the subscription term and are due in accordance with contract terms, which generally provide for payment within 30 days. Variable fees are subject to the same payment terms, although they are generally billed at the end of the period in which they are incurred. The Company also generates revenue from its solutions that allow brands to direct potential consumers from their websites and digital marketing campaigns to authorized resellers. The majority of the Company's contracts have a one year term. 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. Sales taxes collected from customers and remitted to government authorities are excluded from revenue. Customers may subscribe to the Company's SaaS solutions on a self-service or managed-service basis. Self-service subscriptions allow the customer to manage their own activity on the platform. Launch services are also available, although they are not required for the customer to access the platform. Revenue from self-service subscriptions, including subscription fees and fees associated with any elected launch services, is recognized ratably over the subscription term, which is typically one year, beginning on the date the customer has access to the platform. Managed-service subscriptions offer the customer an outsourced, managed platform experience. Implementation services are included with managed-service subscriptions and are necessary to launch on the platform. Revenue from managed-service subscriptions, including subscription fees and fees associated with implementation services, is recognized ratably over the subscription term, which is typically one year, beginning once implementation services are complete. As noted above, customers incur variable fees when the GMV or the advertising spend processed through the platform exceeds the GMV or advertising spend included in their subscriptions. In general, revenue from variable fees is recognized in the period in which the related GMV or advertising spend is processed through the platform. Disaggregation of Revenue The Company's customers are categorized as follows: Retailers. The Company generally categorizes a customer as a retailer if it primarily focuses on selling third-party products. Brands. The Company generally categorizes a customer as a brand if it primarily focuses on selling its own proprietary products. Other. Other is primarily comprised of strategic partnerships. The following table summarizes revenue disaggregation by customer type for the years ended December 31, 2020, 2019 and 2018 (in thousands): 2020 2019 2018 Retailers 87,704 84,316 89,992 Brands 47,999 38,470 32,628 Other 9,369 7,173 8,598 $ 145,072 $ 129,959 $ 131,218 Contracts with Multiple Performance Obligations Customers may elect to purchase a subscription to multiple modules, multiple modules with multiple service levels, or, for certain of the Company's solutions, multiple brands or geographies. The Company evaluates such contracts to determine whether the services to be provided are distinct and accordingly should be accounted for as separate performance obligations. If the Company determines that a contract has multiple performance obligations, the transaction price, which is the total price of the contract, is allocated to each performance obligation based on a relative standalone selling price method. The Company estimates standalone selling price based on observable prices in past transactions for which the product offering subject to the performance obligation has been sold separately. As the performance obligations are satisfied, revenue is recognized as discussed above. Transaction Price Allocated to Future Performance Obligations As the Company typically enters into contracts with customers for a twelve-month subscription term, a substantial majority of its performance obligations that have not yet been satisfied as of December 31, 2020 are part of a contract that has an original expected duration of one year or less. For contracts with an original expected duration of greater than one year, the aggregate transaction price allocated to the unsatisfied performance obligations was $30.6 million as of December 31, 2020, of which $19.0 million is expected to be recognized as revenue over the next twelve months. Deferred Revenue Deferred revenue generally represents the unearned portion of subscription fees. Deferred revenue is recorded when fees are invoiced in advance of performance. Deferred amounts are generally recognized within one year. Deferred revenue is included in the accompanying consolidated balance sheets under "Total current liabilities," net of any long-term portion that is included in "Other long-term liabilities." The following table summarizes deferred revenue activity for the year ended December 31, 2020 (in thousands): Balance, beginning of period Net additions Revenue recognized from deferred revenue Balance, end of period Deferred revenue $ 21,459 109,045 (107,203) $ 23,301 Of the $145.1 million of revenue recognized in the year ended December 31, 2020, $20.0 million was included in deferred revenue at January 1, 2020. Costs to Obtain Contracts The Company capitalizes sales commissions and a portion of other incentive compensation costs that are directly related to obtaining customer contracts and that would not have been incurred if the contract had not been obtained. These costs are included in the accompanying consolidated balance sheets and are classified as "Prepaid expenses and other current assets," net of any long-term portion that is included in "Deferred contract costs, net of current portion." As of December 31, 2020, $7.3 million was included in "Prepaid expenses and other current assets." Deferred contract costs are amortized to sales and marketing expense over the expected period of benefit, which the Company has determined to be 5 years based on the estimated customer relationship period. The following table summarizes deferred contract cost activity for the year ended December 31, 2020 (in thousands): Balance, beginning of period Additions Amortized costs (1) Balance, end of period Deferred contract costs $ 18,414 8,963 (6,044) $ 21,333 (1) Includes contract costs amortized to sales and marketing expense during the period and the impact from foreign currency exchange rate fluctuations.

Income Taxes

Income Taxes	12 Months Ended
	Dec. 31, 2020
Income Tax Disclosure [Abstract]
INCOME TAXES	INCOME TAXESThe components of income (loss) before income taxes for the years ended December 31, 2020, 2019 and 2018 were as follows (in thousands): 2020 2019 2018 Domestic $ 18,176 $ 1,994 $ (10,552) Foreign 1,092 2,177 3,565 Total income (loss) before income taxes $ 19,268 $ 4,171 $ (6,987) The provision for income tax expense (benefit) included the following for the years ended December 31, 2020, 2019 and 2018 (in thousands): 2020 2019 2018 Current: Federal $ (10) $ (10) $ (20) State 460 — — Foreign 32 168 141 Total 482 158 121 Deferred: Federal — — (211) State 3 (18) 12 Foreign (42) 549 692 Total (39) 531 493 Total tax expense $ 443 $ 689 $ 614 Additionally, the Company recorded $(0.1) million of foreign deferred income tax benefit and $0.1 million of foreign current income tax expense in other comprehensive income for the years ended December 31, 2020 and 2019, respectively. There was no impact on other comprehensive income for the year ended December 31, 2018. The Company accounts for the global intangible low taxed income inclusion as a period cost. The components of the Company's net deferred tax assets as of December 31, 2020 and 2019 were as follows (in thousands): 2020 2019 Deferred tax assets: Domestic tax loss carryforwards $ 27,651 $ 31,974 Foreign tax loss carryforwards 7,596 6,098 Stock-based compensation 3,092 3,129 Tax credits 4,345 3,860 Operating lease liability 2,277 3,121 Other assets 3,010 2,062 Valuation allowance (35,393) (38,603) Total deferred tax assets 12,578 11,641 Deferred tax liabilities: Fixed assets 1,000 821 Intangible assets 1,395 491 Capitalized contract costs 5,242 4,468 Right of use assets 1,840 2,478 Other liabilities 21 21 Total deferred tax liabilities 9,498 8,279 Net deferred tax asset $ 3,080 $ 3,362 At December 31, 2020 and 2019, the Company had federal net operating loss, or NOL, carryforwards of $110.3 million and $128.7 million, respectively, which expire beginning in 2026. At December 31, 2020 and 2019, the Company had state NOL carryforwards of $136.5 million and $151.1 million, respectively, which expire beginning in 2021. At December 31, 2020 and 2019, the Company had U.S. federal income tax credit carryforwards of $5.9 million and $5.1 million, respectively, which expire beginning in 2034. The utilization of the NOL and tax credit carryforwards may be subject to limitation under the rules regarding a change in stock ownership as defined under the Internal Revenue Code and state and foreign tax laws. During the year ended December 31, 2020, the Company assessed the limitations on its U.S. federal and state NOL carryforwards and determined that the Company is not prohibited from utilizing its NOL carryforwards, with the exception of $0.9 million and $0.2 million related to U.S. federal and state NOL carryforwards, respectively, from an acquired entity. As of December 31, 2020 and 2019, the Company also had foreign NOL carryforwards for use against future tax in those jurisdictions of $36.6 million and $32.3 million, respectively. The majority of the Company's foreign NOLs can be carried forward indefinitely. A valuation allowance has been recognized to offset deferred tax assets, primarily attributable to NOL carryforwards that the Company has determined are not more likely than not to be realized. There were net decreases in the valuation allowance of $3.2 million and $0.4 million during the years ended December 31, 2020 and 2019, respectively, that were allocable to operations. The Company does not generally consider deferred tax liabilities on indefinite-lived assets as a source of future taxable income available to be able to realize deferred tax assets. However, the Company considers the deferred tax liability associated with an indefinite-lived intangible asset as a source of future taxable income available to be able to realize the deferred tax asset recorded for the U.S. federal NOL carryforwards generated in years ended after December 31, 2017, which can be carried forward indefinitely. 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 asset, which is offset by a valuation allowance. Generally, undistributed earnings of the Company's foreign subsidiaries are indefinitely reinvested offshore and, accordingly, no provision for U.S. federal, state or foreign income taxes has been provided thereon. In the year ended December 31, 2019, the Company determined that the undistributed earnings of its foreign subsidiary located in China are no longer permanently reinvested. Accordingly, the Company recorded a deferred tax liability for this temporary difference. The amount of the deferred tax liability is nominal. The cumulative amount of undistributed earnings of the Company's non-U.S. subsidiaries for the years ended December 31, 2020 and 2019 was $0.5 million and nominal, respectively. 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 funding the working capital needs of its foreign operations through its U.S. operations. In the future, the Company will utilize any foreign undistributed earnings, as well as continued funding from its U.S. operations, to support its continued investment in foreign growth. A reconciliation of the difference between the effective income tax rate and the statutory federal income tax rate for the years ended December 31, 2020, 2019 and 2018 is as follows: 2020 2019 2018 U.S. statutory federal rate 21.0 % 21.0 % 21.0 % Increase (decrease) resulting from: State taxes, net of federal benefit 3.9 3.7 7.8 Nondeductible expenses and excludable income (0.4) 1.6 (3.7) Effect of foreign tax rate differential (0.2) 2.3 (0.5) Uncertain tax positions 1.8 4.9 (3.3) Research and development credit (4.8) (24.8) 15.1 Change in valuation allowance (17.0) (12.0) (36.4) Expiration of NOL carryforwards 0.7 4.0 (1.0) Stock-based compensation (0.9) 6.4 (9.8) Change in statutory tax rates (2.3) 4.0 0.6 Other 0.5 5.4 1.4 Effective tax rate 2.3 % 16.5 % (8.8) % The Company's effective tax rates for the years ended December 31, 2020, 2019 and 2018 are lower than the U.S. federal statutory rate 21% primarily due to operating losses which are subject to a valuation allowance. The Company cannot recognize the tax benefit of operating loss carryforwards generated in certain jurisdictions due to uncertainties relating to future taxable income in those jurisdictions in terms of both its timing and its sufficiency, which would enable the Company to realize the benefits of those carryforwards. The primary reason for the variances in the tax rate impacts from uncertain tax positions, research and development credits, change in valuation allowance, expiration of NOL carryforwards and stock-based compensation for the years ended December 31, 2020, 2019 and 2018 is the variance in income and loss before income taxes between the three years. The decrease and increase in the tax rate impact from change in valuation allowance in the year ended December 31, 2020, as compared to the years ended December 31, 2019 and 2018, respectively, is also partially attributable to the utilization of U.S. federal and state NOLs in the year ended December 31, 2020, which are offset by a valuation allowance. The decrease and increase in the impact on the tax rate from stock-based compensation in the year ended December 31, 2020, as compared to the years ended December 31, 2019 and 2018, respectively, is also partially attributable to an increase in stock-based compensation windfalls and deductions from disqualifying dispositions of incentive stock options in the year ended December 31, 2020. The Company's foreign jurisdictions comprise a mix of income and loss making entities. In the years ended December 31, 2020, 2019 and 2018, foreign income exceeded foreign losses. The Company accounts for uncertain tax provisions in accordance with Accounting Standards Codification Topic 740-10, Income Taxes ("ASC 740-10"). This guidance provides 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. The following table shows the changes in unrecognized tax benefits in accordance with ASC 740-10 for the years ended December 31, 2020, 2019 and 2018 (in thousands): 2020 2019 2018 Balance as of January 1, $ 1,601 $ 1,408 $ 1,282 Increases related to current tax positions 281 183 217 Increases related to prior year tax positions 150 20 12 Decreases related to prior year tax positions (109) (10) (103) Balance as of December 31, $ 1,923 $ 1,601 $ 1,408 Although the ultimate timing of the resolution and/or closure of audits is highly uncertain, the Company believes it is reasonably possible that a de minimis amount of unrecognized tax benefits could reverse in the next twelve months. 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 tax periods 2016 and prior, although carryforward attributes that were generated prior to 2017 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 2015 and prior. No income tax returns are currently under examination by taxing authorities.

Equity Incentive Plans and Stoc

Equity Incentive Plans and Stock-Based Compensation	12 Months Ended
	Dec. 31, 2020
Share-based Payment Arrangement [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, or 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, 2021 the number of shares reserved for issuance under the 2013 Plan increased by 1,451,021 shares. As of December 31, 2020, 3,443,894 shares remained available for future grant under the 2013 Plan. As a result of the adoption of the 2013 Plan, no further grants may be made under the former 2001 Stock Plan. In February 2020, the Company's Compensation Committee implemented changes to the equity compensation program for the Company's executive officers. Beginning in 2020, 50% of each executive's equity awards were granted in the form of performance-based vesting restricted stock units, or PSUs, that are eligible for vesting only if the Company achieves pre-defined targets set by the Compensation Committee for the Company's combined year-over-year revenue growth and adjusted earnings before interest, tax, depreciation and amortization, or EBITDA, margin over a multi-year measurement period (a two-year measurement period for fiscal 2020 grants), subject to the executive's continued service with the Company. For any PSUs to vest, revenue growth must be positive over the performance period. Vesting of these PSU awards is based on a sliding scale of actual performance against the pre-defined goals. The sliding scale ranges from zero vesting and forfeiture of the awards if the Company does not achieve the performance threshold, to an award of up to 150% of the target number of awards if the pre-defined maximum performance is achieved. As soon as reasonably practicable after the completion of the performance period, the Compensation Committee will determine the level of attainment of the performance goal and if the performance threshold is achieved, on the second anniversary of the grant date, subject to the executive's continued service as of that date, 50% of the earned PSU awards will vest and, on the third anniversary of the grant date, the remaining 50% of earned PSU awards will vest, subject to the executive's continued service as of that date. The Committee may make adjustments to the manner in which the achievement is determined as it deems equitable and appropriate to exclude the effect of unusual, non-recurring or infrequent matters, transactions or events affecting the Company or its consolidated financial statements; changes in accounting principles, practices or policies or in tax laws or other laws or requirements; or other similar events, matters or changed circumstances. Each adjustment, if any, shall be made solely for the purpose of maintaining the intended economics of the award in light of changed circumstances to prevent the dilution or enlargement of the executive's rights with respect to the PSUs. The fair value of the PSU awards is determined using the Company's stock price on the grant date. These awards are equity classified and will be expensed over the requisite service period based on the extent to which achievement of the performance metrics is probable. Stock-based compensation expense is included in the following line items in the accompanying consolidated statements of operations for the years ended December 31, 2020, 2019 and 2018 (in thousands): 2020 2019 2018 Cost of revenue $ 972 $ 995 $ 911 Sales and marketing 2,792 2,385 3,144 Research and development 2,168 1,898 2,152 General and administrative 4,268 3,698 4,391 $ 10,200 $ 8,976 $ 10,598 Stock Option Awards 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 estimated based on the historical volatility of the Company's stock. 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, 2019 and 2018: 2019 2018 Risk-free interest rate 1.8% - 2.5% 2.7% - 2.9% Expected term (years) 6.25 6.25 Expected volatility 37% - 41% 43% Dividend yield 0% 0% There were no stock options granted during the year ended December 31, 2020. The following is a summary of the option activity for the year ended December 31, 2020: Number of Weighted Average Weighted Aggregate (in years) (in thousands) Outstanding balance at December 31, 2019 2,196,766 $ 10.47 Granted — — Exercised (440,174) 8.69 Forfeited (5,355) 11.60 Expired (47,992) 12.38 Outstanding balance at December 31, 2020 1,703,245 $ 10.87 5.69 $ 9,160 Exercisable at December 31, 2020 1,189,509 $ 10.38 4.80 $ 7,122 Vested and expected to vest at December 31, 2020 1,594,971 $ 10.80 5.55 $ 8,727 The weighted average grant date fair value for the Company's stock options granted during the years ended December 31, 2019 and 2018 was $4.51 and $5.98 per share, respectively. The total fair value of stock options vested during the years ended December 31, 2020, 2019 and 2018 was $1.5 million, $1.8 million and $1.5 million, respectively. The total compensation cost related to nonvested stock options not yet recognized as of December 31, 2020 was $0.6 million and will be recognized over a weighted average period of approximately 1.3 years. The aggregate intrinsic value of stock options exercised during the years ended December 31, 2020, 2019, and 2018 was $2.3 million, $0.2 million and $0.6 million, respectively. Restricted Stock Units and Performance Stock Units The following table summarizes the RSU and PSU activity for the year ended December 31, 2020: Number of RSUs Weighted Average Grant-Date Fair Value Number of PSUs Weighted Average Grant-Date Fair Value Unvested as of December 31, 2019 2,086,646 $ 10.93 — $ — Granted 958,055 11.32 142,317 9.27 Vested (743,730) 11.21 — — Forfeited (240,143) 10.36 — — Unvested as of December 31, 2020 2,060,828 $ 11.08 142,317 $ 9.27

Net Income (Loss) Per Share

Net Income (Loss) Per Share	12 Months Ended
	Dec. 31, 2020
Earnings Per Share [Abstract]
NET INCOME (LOSS) PER SHARE	NET INCOME (LOSS) PER SHARE The following table summarizes the calculation of basic and diluted net income (loss) per share for the years ended December 31, 2020, 2019 and 2018 (in thousands, except share and per share data): 2020 2019 2018 Basic: Net income (loss) $ 18,825 $ 3,482 $ (7,601) Weighted average common shares outstanding, basic 28,616,401 27,886,278 27,138,274 Basic net income (loss) per share $ 0.66 $ 0.12 $ (0.28) Diluted: Net income (loss) $ 18,825 $ 3,482 $ (7,601) Weighted average common shares outstanding, basic 28,616,401 27,886,278 27,138,274 Dilutive effect of: Stock options 383,607 167,208 — Unvested RSUs 1,035,253 763,491 — Diluted weighted average common shares outstanding 30,035,261 28,816,977 27,138,274 Diluted net income (loss) per share $ 0.63 $ 0.12 $ (0.28) For the year ended December 31, 2018, the Company incurred a net loss and, therefore, the effect of the Company's outstanding stock options and unvested RSUs were not included in the calculation of diluted net loss per share as the effect would be anti-dilutive. The following equity instruments have been excluded from the calculation of diluted net income (loss) per share because the effect is anti-dilutive for the years ended December 31, 2020, 2019 and 2018: 2020 2019 2018 Stock options 437,927 1,626,757 2,208,141 RSUs 60,674 278,937 2,216,430

Restructuring

Restructuring	12 Months Ended
	Dec. 31, 2020
Restructuring and Related Activities [Abstract]
RESTRUCTURING	RESTRUCTURING In the third quarter of 2019, the Company implemented a plan to reduce its expenses and align its operations with evolving business needs, or the 2019 Actions. As part of this strategic initiative, the Company reduced its global workforce by approximately 10% and discontinued its physical operations in China. As a result of the implementation of the 2019 Actions, the Company paid and recognized severance and related costs of $1.4 million during the year ended December 31, 2019. These costs are included in the following line items in the accompanying consolidated statements of operations (in thousands): Cost of revenue $ 238 Sales and marketing 369 Research and development 142 General and administrative 560 Other (expense) income, net 120 $ 1,429

Segment and Geographic Informat

Segment and Geographic Information	12 Months Ended
	Dec. 31, 2020
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, or 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, 2020 and 2019. The following tables summarize revenue by geography and by product for the years ended December 31, 2020, 2019 and 2018 (in thousands): 2020 2019 2018 Revenue by geography (1) : Domestic $ 108,556 $ 97,111 $ 100,442 International 36,516 32,848 30,776 Total $ 145,072 $ 129,959 $ 131,218 Revenue by product: Marketplaces $ 107,425 $ 95,757 $ 96,321 Digital marketing 21,424 19,683 18,919 Other 16,223 14,519 15,978 Total $ 145,072 $ 129,959 $ 131,218 (1) Certain prior period amounts have been reclassified to conform to current period presentation. These reclassifications had no impact on the reported total revenue for the period.

Retirement Plan

Retirement Plan	12 Months Ended
	Dec. 31, 2020
Retirement Benefits [Abstract]
RETIREMENT PLANS	RETIREMENT PLANSThe Company provides retirement plans whereby participants may elect to contribute a portion of their annual compensation to the plans, after complying with certain requirements and subject to certain limitations. The Company contributed an aggregate of $1.9 million to the plans for the year ended December 31, 2020 and $1.7 million for each of the years ended December 31, 2019 and 2018.

Significant Accounting Polici_2

Significant Accounting Policies (Policies)	12 Months Ended
	Dec. 31, 2020
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.
Recent Accounting Pronouncements	Recent Accounting Pronouncements Standard Description Effect on the Financial Statements or Other Significant Matters Standards that the Company adopted effective January 1, 2020 Financial Instruments: Accounting Standards Update, or ASU, 2016-13, Financial Instruments - Credit Losses (Topic 326) Effective date: January 1, 2020 The standard replaces the incurred loss impairment methodology in current U.S. GAAP (defined below) with a methodology that reflects expected credit losses. The update is intended to provide financial statement users with more useful information about expected credit losses. The Company adopted this standard effective January 1, 2020. The adoption did not have a material impact on its consolidated financial statements. Intangibles: ASU 2018-15, Intangibles -Goodwill and Other - Internal-Use Software (Subtopic 350-40) Effective date: January 1, 2020 This standard aligns the requirements for capitalizing implementation costs incurred in a hosting arrangement that is a service contract with the requirements for capitalizing implementation costs incurred to develop or obtain internal-use software. The Company adopted this standard effective January 1, 2020. The adoption did not have a material impact on its consolidated financial statements. Income Taxes: ASU 2019-12, Income Taxes (Topic 740) Simplifying the Accounting for Income Taxes Effective date: January 1, 2020 This standard amends the approaches and methodologies in accounting for income taxes during interim periods and makes changes to certain income tax classifications. The new standard allows exceptions to the use of the incremental approach for intra-period tax allocation, when there is a loss from continuing operations and income or a gain from other items, and to the general methodology for calculating income taxes in an interim period, when a year-to-date loss exceeds the anticipated loss for the year. The standard also requires franchise or similar taxes partially based on income to be reported as income tax and the effects of enacted changes in tax laws or rates to be included in the annual effective tax rate computation from the date of enactment. Lastly, the Company would be required to evaluate when the step-up in the tax basis of goodwill is part of the business combination and when it should be considered a separate transaction. ASU 2019-12 is effective for fiscal years, and interim periods within those fiscal years, beginning after December 15, 2020. The Company early adopted this standard effective January 1, 2020. The early adoption did not have a material impact on its consolidated financial statements or related disclosures.
Use of Estimates	Use of Estimates The preparation of financial statements in conformity with United States generally accepted accounting principles, or 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, income taxes, assumptions used for purposes of determining stock-based compensation, leases, including estimating lease terms and extensions, and revenue recognition, including standalone selling prices for contracts with multiple performance obligations and the expected period of benefit for deferred contract costs, among others. Estimates and assumptions are also required to value assets acquired and liabilities assumed as well as contingent consideration, where applicable, in conjunction with business combinations. 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 with an original maturity of 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.
Revenue Recognition, Cost of Sales, Deferred Revenue and Costs to Obtain Contracts	Revenue Recognition Revenue is recognized when a customer obtains control of promised services, in an amount that reflects the consideration the Company expects to be entitled to receive in exchange for those services. In determining the amount of revenue to be recognized, the Company performs the following steps: (i) identification of the contract with a customer; (ii) identification of the promised services in the contract and determination of whether the promised services are performance obligations, including whether they are distinct in the context of the contract; (iii) determination of the transaction price; (iv) allocation of the transaction price to the performance obligations based on estimated selling prices; and (v) recognition of revenue when (or as) the Company satisfies each performance obligation. Refer to Note 8, "Revenue from Contracts with Customers" for a detailed discussion of accounting policies related to revenue recognition, including deferred revenue and sales commissions. Cost of Revenue Cost of revenue primarily consists of personnel and related costs, including salaries, bonuses, payroll taxes and stock-based compensation, co-location facility costs for the Company's data centers, depreciation expense for computer equipment and amortization of capitalized software 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 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. 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. The acquisition of Blueboard, a private limited company organized under the laws of France ("BlueBoard") on July 23, 2020 includes a contingent consideration arrangement, as described in Note 4 below. Contingent consideration was measured at fair value at the acquisition date and is remeasured at fair value at each reporting date until the contingency is resolved. The fair value of the contingent consideration related to the BlueBoard acquisition was estimated utilizing Black-Scholes option pricing models in which various scenarios for achievement of the financial targets and resulting payouts are then discounted to determine the present value of the resulting liability. Key assumptions used in the measurement of fair value of contingent consideration include the forecasted revenue growth, revenue volatility and discount rates among other assumptions. Changes in any valuation inputs in isolation may result in a significantly lower or higher fair value measurement in the future. Subsequent changes in the fair value of contingent consideration are recognized within general and administrative expenses in the Company’s consolidated statements of operations. As of December 31, 2020, the fair value of the contingent consideration was $1.3 million, of which $0.6 million is recorded in "Other current liabilities" and $0.7 million is recorded in "Other long-term liabilities." The following table presents the changes to the Company's liability for acquisition-related contingent consideration for the year ended December 31, 2020 (in thousands): Balance as of December 31, 2019 $ — Acquisition 1,516 Change in fair value (186) Balance as of December 31, 2020 $ 1,330
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 equivalents accounts exceed federally insured limits. The Company has not experienced any losses on its cash and cash equivalents accounts to date. To manage accounts receivable risk, the Company maintains an allowance for credit losses.
Accounts Receivable and Allowance for Doubtful Accounts	Accounts Receivable and Allowance for Credit Losses The Company extends credit to customers without requiring collateral. Accounts receivable are stated at amortized cost, net of an allowance for credit losses. The Company records an allowance for credit losses at the time that accounts receivable are initially recorded based on its consideration of the current economic environment, expectations of future economic conditions, the Company's historical collection experience and a loss-rate approach whereby impairment is calculated
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 capitalized software development costs 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 and amortization methodology used in computing amortization are as follows: Estimated Useful Lives Amortization Methodology Customer relationships 7 years Straight-line Acquired technology 7 years Straight-line
Impairment of Long-Lived Assets	Impairment of Long-Lived AssetsThe Company reviews long-lived 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.
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. The Company recorded goodwill in connection with its business acquisitions. Refer to Note 4 below for information regarding goodwill recorded in connection with the acquisition of BlueBoard. Goodwill is not amortized, but is subject to an annual impairment test, as described below. The Company has determined that it has a single, entity-wide reporting unit. The Company first assessed qualitative factors to determine whether it was more likely than not that the fair value of its single reporting unit was less than its carrying amount as a basis for determining whether it is necessary to perform the two-step goodwill impairment test under ASU No. 2011-08, Goodwill and Other (Topic 350): Testing Goodwill for Impairment. If the qualitative factors had indicated that it was more likely than not that the fair value of the reporting unit was less than its carrying amount, the Company would have tested 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. The Company performs its annual goodwill impairment analysis as of October 1, the first day of the fourth quarter. As a result of the Company's annual impairment analysis as of October 1, 2020 and 2019, goodwill was not considered impaired and, as such, no impairment charges were recorded.
Operating and Finance Lease Commitments	The Company leases office facilities and certain equipment under non-cancelable operating and finance leases. The Company determines if an arrangement is a lease and whether its classification is operating or finance at inception. Leases with an initial term of twelve months or less that are not expected to be renewed are not recorded on the balance sheet. For such leases, lease expense for minimum lease payments is recognized on a straight-line basis over the lease term. Certain operating leases include options to renew, with renewal terms extending up to 10 years, subject to certain conditions and notice obligations set forth in the lease agreements. The exercise of lease renewal options is at the Company's discretion. Operating lease right of use, or ROU, assets represent the Company's right to use an underlying asset for the lease term and lease liabilities represent the Company's obligation to make lease payments arising from the lease. Operating lease ROU assets and operating lease liabilities are recognized based on the present value of the future minimum lease payments over the
Advertising Costs	Advertising CostsThe Company expenses advertising costs as incurred.
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
Foreign Currency Translation	Foreign Currency TranslationThe functional currency of the Company's non-U.S. operations is the local currency. Monetary assets and liabilities denominated in foreign currencies are translated into U.S. dollars at exchange rates prevailing at the balance sheet dates. Non-monetary assets and liabilities are translated at the historical rates in effect when the assets were acquired or obligations incurred. Revenue and expenses are translated into U.S. dollars using the average rates of exchange prevailing during the period. Translation gains or losses are included as a component of accumulated other comprehensive loss in stockholders' equity. Gains and losses resulting from foreign currency transactions are recognized as other income (expense).
Stock-Based Compensation	Stock-Based Compensation The Company accounts for stock-based compensation awards, which include stock options, time-based restricted stock units, or RSUs, and performance-based vesting restricted stock units, or PSUs, 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.
Basic and Diluted Loss per Common Share	Basic and Diluted Income (Loss) per Common Share Basic net income (loss) per share is calculated by dividing net income (loss) by the weighted-average number of shares of common stock outstanding for the period. Diluted net income (loss) per share is calculated giving effect to all potentially dilutive shares of common stock, including stock options, RSUs and PSUs. The dilutive effect of outstanding awards is reflected in diluted earnings per share by application of the treasury stock method.

Significant Accounting Polici_3

Significant Accounting Policies (Tables)	12 Months Ended
	Dec. 31, 2020
Accounting Policies [Abstract]
Schedule of Depreciation and Amortization	Depreciation and amortization expense is included in the following line items in the accompanying consolidated statements of operations for the years ended December 31, 2020, 2019 and 2018 (in thousands): 2020 2019 2018 Cost of revenue $ 4,211 $ 3,942 $ 3,610 Sales and marketing 624 775 884 Research and development 257 353 371 General and administrative 1,421 1,266 1,229 $ 6,513 $ 6,336 $ 6,094
New Accounting Pronouncements	Standard Description Effect on the Financial Statements or Other Significant Matters Standards that the Company adopted effective January 1, 2020 Financial Instruments: Accounting Standards Update, or ASU, 2016-13, Financial Instruments - Credit Losses (Topic 326) Effective date: January 1, 2020 The standard replaces the incurred loss impairment methodology in current U.S. GAAP (defined below) with a methodology that reflects expected credit losses. The update is intended to provide financial statement users with more useful information about expected credit losses. The Company adopted this standard effective January 1, 2020. The adoption did not have a material impact on its consolidated financial statements. Intangibles: ASU 2018-15, Intangibles -Goodwill and Other - Internal-Use Software (Subtopic 350-40) Effective date: January 1, 2020 This standard aligns the requirements for capitalizing implementation costs incurred in a hosting arrangement that is a service contract with the requirements for capitalizing implementation costs incurred to develop or obtain internal-use software. The Company adopted this standard effective January 1, 2020. The adoption did not have a material impact on its consolidated financial statements. Income Taxes: ASU 2019-12, Income Taxes (Topic 740) Simplifying the Accounting for Income Taxes Effective date: January 1, 2020 This standard amends the approaches and methodologies in accounting for income taxes during interim periods and makes changes to certain income tax classifications. The new standard allows exceptions to the use of the incremental approach for intra-period tax allocation, when there is a loss from continuing operations and income or a gain from other items, and to the general methodology for calculating income taxes in an interim period, when a year-to-date loss exceeds the anticipated loss for the year. The standard also requires franchise or similar taxes partially based on income to be reported as income tax and the effects of enacted changes in tax laws or rates to be included in the annual effective tax rate computation from the date of enactment. Lastly, the Company would be required to evaluate when the step-up in the tax basis of goodwill is part of the business combination and when it should be considered a separate transaction. ASU 2019-12 is effective for fiscal years, and interim periods within those fiscal years, beginning after December 15, 2020. The Company early adopted this standard effective January 1, 2020. The early adoption did not have a material impact on its consolidated financial statements or related disclosures.
Schedule of Business Acquisition Contingent Consideration	The following table presents the changes to the Company's liability for acquisition-related contingent consideration for the year ended December 31, 2020 (in thousands): Balance as of December 31, 2019 $ — Acquisition 1,516 Change in fair value (186) Balance as of December 31, 2020 $ 1,330
Changes in Allowance for Doubtful Accounts	The following table presents the changes in the Company's allowance for credit losses during the year ended December 31, 2020 (in thousands): Balance, Provision for credit losses (1) Write-offs, net of recoveries Balance, Allowance for credit losses: Year ended December 31, 2020 $ 733 525 (841) $ 417
Schedule of Property and Equipment	The estimated useful lives for significant property and equipment categories are generally as follows: Purchased software, including capitalized software development costs 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, 2020 and 2019 (in thousands): 2020 2019 Purchased software, including capitalized software development costs $ 17,303 $ 13,965 Computer hardware 9,541 8,975 Furniture and office equipment 2,388 2,369 Leasehold improvements 7,368 7,244 Construction in process 48 46 36,648 32,599 Less: accumulated depreciation (27,941) (23,002) Property and equipment, net $ 8,707 $ 9,597
Schedule of Intangible Assets	The estimated useful lives and amortization methodology used in computing amortization are as follows: Estimated Useful Lives Amortization Methodology Customer relationships 7 years Straight-line Acquired technology 7 years Straight-line Intangible assets consisted of the following as of December 31, 2020 and 2019 (in thousands): December 31, 2020 Gross Carrying Accumulated Net Carrying Weighted Average Customer relationships $ 2,603 $ (1,940) $ 663 7.0 Acquired technology 5,367 (1,875) 3,492 7.0 Total $ 7,970 $ (3,815) $ 4,155 7.0 December 31, 2019 Gross Carrying Accumulated Net Carrying Weighted Average Customer relationships $ 2,230 $ (1,598) $ 632 7.0 Acquired technology 2,030 (1,377) 653 7.0 Total $ 4,260 $ (2,975) $ 1,285 7.0

Property and Equipment (Tables)

Property and Equipment (Tables)	12 Months Ended
	Dec. 31, 2020
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 capitalized software development costs 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, 2020 and 2019 (in thousands): 2020 2019 Purchased software, including capitalized software development costs $ 17,303 $ 13,965 Computer hardware 9,541 8,975 Furniture and office equipment 2,388 2,369 Leasehold improvements 7,368 7,244 Construction in process 48 46 36,648 32,599 Less: accumulated depreciation (27,941) (23,002) Property and equipment, net $ 8,707 $ 9,597

Business Combination, Goodwil_2

Business Combination, Goodwill and Intangible Assets (Tables)	12 Months Ended
	Dec. 31, 2020
Goodwill and Intangible Assets Disclosure [Abstract]
Schedule of Goodwill	The following table shows the changes in the carrying amount of goodwill for the year ended December 31, 2020 (in thousands): Balance as of December 31, 2019 $ 23,486 Goodwill attributable to the BlueBoard acquisition 7,504 Balance as of December 31, 2020 $ 30,990
Schedule of Intangible Assets	The estimated useful lives and amortization methodology used in computing amortization are as follows: Estimated Useful Lives Amortization Methodology Customer relationships 7 years Straight-line Acquired technology 7 years Straight-line Intangible assets consisted of the following as of December 31, 2020 and 2019 (in thousands): December 31, 2020 Gross Carrying Accumulated Net Carrying Weighted Average Customer relationships $ 2,603 $ (1,940) $ 663 7.0 Acquired technology 5,367 (1,875) 3,492 7.0 Total $ 7,970 $ (3,815) $ 4,155 7.0 December 31, 2019 Gross Carrying Accumulated Net Carrying Weighted Average Customer relationships $ 2,230 $ (1,598) $ 632 7.0 Acquired technology 2,030 (1,377) 653 7.0 Total $ 4,260 $ (2,975) $ 1,285 7.0
Expected Future Amortization Expense	As of December 31, 2020, expected amortization expense over the remaining intangible asset lives is as follows (in thousands): Year Ending December 31, 2021 $ 1,048 2022 596 2023 596 2024 557 2025 530 Thereafter 828 Total $ 4,155

Leases (Tables)

Leases (Tables)	12 Months Ended
	Dec. 31, 2020
Leases [Abstract]
Lease Assets And Lease Liabilities [Table Text Block]	The following table summarizes the Company's lease assets and liabilities as of December 31, 2020 and 2019 (in thousands): December 31, 2020 December 31, 2019 Assets Operating lease right of use assets $ 8,141 $ 11,128 Finance lease assets, included in Property and equipment, net (1) 495 1,917 Total leased assets $ 8,636 $ 13,045 Liabilities Current Operating lease liabilities, included in Other current liabilities $ 4,716 $ 4,177 Finance lease liabilities, included in Other current liabilities 15 1,418 Long-term Long-term operating leases, net of current portion 5,394 9,767 Finance leases, net of current portion $ 8 $ 27 Total lease liabilities $ 10,133 $ 15,389 (1) Finance leases are presented net of accumulated amortization of $5.8 million and $4.4 million as of December 31, 2020 and 2019, respectively.
Schedule of Lease Expense Components	The following table summarizes the components of lease expense for the years ended December 31, 2020 and 2019 (in thousands): 2020 2019 Operating lease cost, included in General and administrative expense (1) $ 4,093 $ 4,808 Finance lease cost: Amortization of leased assets, included in General and administrative expense 1,421 2,041 Interest on lease liabilities, included in Other income (expense), net 35 140 Less: sublease income, reducing rent expense in General and administrative expense (2) (167) (168) Net lease cost $ 5,382 $ 6,821 (1) Excludes short-term lease costs of $0.2 million and $0.4 million for the years ended December 31, 2020 and 2019, respectively. (2) The Company subleases space to a third party for which it anticipates receiving $0.2 million in annual rental payments during the term of the sublease agreement, which is through August 2022.
Other Information Related To Leases [Table Text Block]	The following table summarizes other information related to leases for the years ended December 31, 2020 and 2019 (in thousands): 2020 2019 Supplemental cash flows information Cash paid for amounts included in the measurement of lease liabilities: Operating cash outflows from operating leases $ 4,501 $ 4,852 Operating cash outflows from finance leases 105 216 Financing cash outflows from finance leases 1,422 2,209 Weighted-average remaining lease term (years) Operating leases 2.22 3.20 Finance leases 0.41 1.37 Weighted-average discount rate Operating leases 5.48 % 5.50 % Finance leases 7.12 % 7.28 %
Lessee, Operating Lease, Liability, Maturity [Table Text Block]	The following table summarizes maturities of lease liabilities as of December 31, 2020 (in thousands): Operating Leases Finance Leases 2021 $ 5,130 $ 15 2022 4,360 8 2023 1,236 — Total lease payments $ 10,726 $ 23 Less: imputed interest (616) — Present value of lease liabilities $ 10,110 $ 23

Revenue from Contracts with C_2

Revenue from Contracts with Customers (Tables)	12 Months Ended
	Dec. 31, 2020
Revenue from Contract with Customer [Abstract]
Disaggregation of Revenue	The following table summarizes revenue disaggregation by customer type for the years ended December 31, 2020, 2019 and 2018 (in thousands): 2020 2019 2018 Retailers 87,704 84,316 89,992 Brands 47,999 38,470 32,628 Other 9,369 7,173 8,598 $ 145,072 $ 129,959 $ 131,218
Deferred Revenue	The following table summarizes deferred revenue activity for the year ended December 31, 2020 (in thousands): Balance, beginning of period Net additions Revenue recognized from deferred revenue Balance, end of period Deferred revenue $ 21,459 109,045 (107,203) $ 23,301
Deferred Contract Costs	The following table summarizes deferred contract cost activity for the year ended December 31, 2020 (in thousands): Balance, beginning of period Additions Amortized costs (1) Balance, end of period Deferred contract costs $ 18,414 8,963 (6,044) $ 21,333 (1) Includes contract costs amortized to sales and marketing expense during the period and the impact from foreign currency exchange rate fluctuations.

Income Taxes (Tables)

Income Taxes (Tables)	12 Months Ended
	Dec. 31, 2020
Income Tax Disclosure [Abstract]
Components of Income (Loss) before Income Taxes	The components of income (loss) before income taxes for the years ended December 31, 2020, 2019 and 2018 were as follows (in thousands): 2020 2019 2018 Domestic $ 18,176 $ 1,994 $ (10,552) Foreign 1,092 2,177 3,565 Total income (loss) before income taxes $ 19,268 $ 4,171 $ (6,987)
Schedule of Provision for Income Tax Expense (Benefit)	The provision for income tax expense (benefit) included the following for the years ended December 31, 2020, 2019 and 2018 (in thousands): 2020 2019 2018 Current: Federal $ (10) $ (10) $ (20) State 460 — — Foreign 32 168 141 Total 482 158 121 Deferred: Federal — — (211) State 3 (18) 12 Foreign (42) 549 692 Total (39) 531 493 Total tax expense $ 443 $ 689 $ 614
Components of Net Deferred Tax Assets (Liabilities)	The components of the Company's net deferred tax assets as of December 31, 2020 and 2019 were as follows (in thousands): 2020 2019 Deferred tax assets: Domestic tax loss carryforwards $ 27,651 $ 31,974 Foreign tax loss carryforwards 7,596 6,098 Stock-based compensation 3,092 3,129 Tax credits 4,345 3,860 Operating lease liability 2,277 3,121 Other assets 3,010 2,062 Valuation allowance (35,393) (38,603) Total deferred tax assets 12,578 11,641 Deferred tax liabilities: Fixed assets 1,000 821 Intangible assets 1,395 491 Capitalized contract costs 5,242 4,468 Right of use assets 1,840 2,478 Other liabilities 21 21 Total deferred tax liabilities 9,498 8,279 Net deferred tax asset $ 3,080 $ 3,362
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, 2020, 2019 and 2018 is as follows: 2020 2019 2018 U.S. statutory federal rate 21.0 % 21.0 % 21.0 % Increase (decrease) resulting from: State taxes, net of federal benefit 3.9 3.7 7.8 Nondeductible expenses and excludable income (0.4) 1.6 (3.7) Effect of foreign tax rate differential (0.2) 2.3 (0.5) Uncertain tax positions 1.8 4.9 (3.3) Research and development credit (4.8) (24.8) 15.1 Change in valuation allowance (17.0) (12.0) (36.4) Expiration of NOL carryforwards 0.7 4.0 (1.0) Stock-based compensation (0.9) 6.4 (9.8) Change in statutory tax rates (2.3) 4.0 0.6 Other 0.5 5.4 1.4 Effective tax rate 2.3 % 16.5 % (8.8) %
Schedule of Unrecognized Tax Benefits Roll Forward	The following table shows the changes in unrecognized tax benefits in accordance with ASC 740-10 for the years ended December 31, 2020, 2019 and 2018 (in thousands): 2020 2019 2018 Balance as of January 1, $ 1,601 $ 1,408 $ 1,282 Increases related to current tax positions 281 183 217 Increases related to prior year tax positions 150 20 12 Decreases related to prior year tax positions (109) (10) (103) Balance as of December 31, $ 1,923 $ 1,601 $ 1,408

Equity Incentive Plans and St_2

Equity Incentive Plans and Stock-Based Compensation (Tables)	12 Months Ended
	Dec. 31, 2020
Share-based Payment Arrangement [Abstract]
Summary of Stock-Based Compensation Expense	Stock-based compensation expense is included in the following line items in the accompanying consolidated statements of operations for the years ended December 31, 2020, 2019 and 2018 (in thousands): 2020 2019 2018 Cost of revenue $ 972 $ 995 $ 911 Sales and marketing 2,792 2,385 3,144 Research and development 2,168 1,898 2,152 General and administrative 4,268 3,698 4,391 $ 10,200 $ 8,976 $ 10,598
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, 2019 and 2018: 2019 2018 Risk-free interest rate 1.8% - 2.5% 2.7% - 2.9% Expected term (years) 6.25 6.25 Expected volatility 37% - 41% 43% Dividend yield 0% 0%
Summary of Stock Option Activity	The following is a summary of the option activity for the year ended December 31, 2020: Number of Weighted Average Weighted Aggregate (in years) (in thousands) Outstanding balance at December 31, 2019 2,196,766 $ 10.47 Granted — — Exercised (440,174) 8.69 Forfeited (5,355) 11.60 Expired (47,992) 12.38 Outstanding balance at December 31, 2020 1,703,245 $ 10.87 5.69 $ 9,160 Exercisable at December 31, 2020 1,189,509 $ 10.38 4.80 $ 7,122 Vested and expected to vest at December 31, 2020 1,594,971 $ 10.80 5.55 $ 8,727
Summary of Restricted Stock Units Award Activity	The following table summarizes the RSU and PSU activity for the year ended December 31, 2020: Number of RSUs Weighted Average Grant-Date Fair Value Number of PSUs Weighted Average Grant-Date Fair Value Unvested as of December 31, 2019 2,086,646 $ 10.93 — $ — Granted 958,055 11.32 142,317 9.27 Vested (743,730) 11.21 — — Forfeited (240,143) 10.36 — — Unvested as of December 31, 2020 2,060,828 $ 11.08 142,317 $ 9.27

Net Income (Loss) Per Share (Ta

Net Income (Loss) Per Share (Tables)	12 Months Ended
	Dec. 31, 2020
Earnings Per Share [Abstract]
Schedule of Earnings Per Share, Basic and Diluted [Table Text Block]	The following table summarizes the calculation of basic and diluted net income (loss) per share for the years ended December 31, 2020, 2019 and 2018 (in thousands, except share and per share data): 2020 2019 2018 Basic: Net income (loss) $ 18,825 $ 3,482 $ (7,601) Weighted average common shares outstanding, basic 28,616,401 27,886,278 27,138,274 Basic net income (loss) per share $ 0.66 $ 0.12 $ (0.28) Diluted: Net income (loss) $ 18,825 $ 3,482 $ (7,601) Weighted average common shares outstanding, basic 28,616,401 27,886,278 27,138,274 Dilutive effect of: Stock options 383,607 167,208 — Unvested RSUs 1,035,253 763,491 — Diluted weighted average common shares outstanding 30,035,261 28,816,977 27,138,274 Diluted net income (loss) per share $ 0.63 $ 0.12 $ (0.28)
Schedule of Securities Excluded from Calculation of Weighted Average Common Shares Outstanding	The following equity instruments have been excluded from the calculation of diluted net income (loss) per share because the effect is anti-dilutive for the years ended December 31, 2020, 2019 and 2018: 2020 2019 2018 Stock options 437,927 1,626,757 2,208,141 RSUs 60,674 278,937 2,216,430

Restructuring (Tables)

Restructuring (Tables)	12 Months Ended
	Dec. 31, 2020
Restructuring and Related Activities [Abstract]
Schedule of Severance Costs	These costs are included in the following line items in the accompanying consolidated statements of operations (in thousands): Cost of revenue $ 238 Sales and marketing 369 Research and development 142 General and administrative 560 Other (expense) income, net 120 $ 1,429

Segment and Geographic Inform_2

Segment and Geographic Information (Tables)	12 Months Ended
	Dec. 31, 2020
Segment Reporting [Abstract]
Summary of Revenue by Geography	The following tables summarize revenue by geography and by product for the years ended December 31, 2020, 2019 and 2018 (in thousands): 2020 2019 2018 Revenue by geography (1) : Domestic $ 108,556 $ 97,111 $ 100,442 International 36,516 32,848 30,776 Total $ 145,072 $ 129,959 $ 131,218 Revenue by product: Marketplaces $ 107,425 $ 95,757 $ 96,321 Digital marketing 21,424 19,683 18,919 Other 16,223 14,519 15,978 Total $ 145,072 $ 129,959 $ 131,218

Significant Accounting Polici_4

Significant Accounting Policies Significant Accounting Policies - Depreciation and Amortization (Details) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2020	Dec. 31, 2019	Dec. 31, 2018
Schedule of Depreciation and Amortization [Line Items]
Depreciation and amortization	$ 6,513	$ 6,336	$ 6,094
Cost of revenue
Schedule of Depreciation and Amortization [Line Items]
Depreciation and amortization	4,211	3,942	3,610
Sales and marketing
Schedule of Depreciation and Amortization [Line Items]
Depreciation and amortization	624	775	884
Research and development
Schedule of Depreciation and Amortization [Line Items]
Depreciation and amortization	257	353	371
General and administrative
Schedule of Depreciation and Amortization [Line Items]
Depreciation and amortization	$ 1,421	$ 1,266	$ 1,229

Significant Accounting Polici_5

Significant Accounting Policies - Additional Information (Detail)	12 Months Ended
	Dec. 31, 2020USD ($)segment	Dec. 31, 2019USD ($)	Dec. 31, 2018USD ($)	Jul. 23, 2020USD ($)
Significant Accounting Policies [Line Items]
Impairment of long-lived assets	$ 0	$ 0
Number of reportable segments | segment	1
Goodwill impairment loss	$ 0	0
Advertising expense	3,500,000	4,200,000	$ 5,700,000
Unrecognized tax benefits, income tax penalties and interest accrued	0	0
BlueBoard
Significant Accounting Policies [Line Items]
Business combination, contingent consideration, liability	1,330,000	$ 0		$ 1,500,000
Other Current Liabilities | BlueBoard
Significant Accounting Policies [Line Items]
Business combination, contingent consideration, liability	600,000
Other Noncurrent Liabilities | BlueBoard
Significant Accounting Policies [Line Items]
Business combination, contingent consideration, liability	$ 700,000

Significant Accounting Polici_6

Significant Accounting Policies - Schedule of Contingent Consideration (Details) $ in Thousands	12 Months Ended
	Dec. 31, 2020USD ($)
Business Acquisition, Contingent Consideration [Roll Forward]
Acquisition	$ 1,516
Change in fair value	(186)
BlueBoard
Business Acquisition, Contingent Consideration [Roll Forward]
Balance as of December 31, 2019	0
Balance as of December 31, 2020	$ 1,330

Significant Accounting Polici_7

Significant Accounting Policies - Allowance for Doubtful Accounts (Details) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2020	Dec. 31, 2019	Dec. 31, 2018
Accounts Receivable, Allowance for Credit Loss [Roll Forward]
Balance, beginning of period	$ 733
Provision for credit losses	525	$ 1,147	$ 991
Write-offs, net of recoveries	(841)
Balance, end of period	$ 417	$ 733

Significant Accounting Polici_8

Significant Accounting Policies Significant Accounting Policies - Software Development Costs (Details) - USD ($) $ in Millions	12 Months Ended
	Dec. 31, 2020	Dec. 31, 2019	Dec. 31, 2018
Accounting Policies [Abstract]
Software development costs capitalized during the period	$ 3.1	$ 3
Amortization expense related to capitalized internally developed software	1.8	0.8	$ 0.3
Capitalized internally developed software, net	$ 4.2	$ 2.9

Significant Accounting Polici_9

Significant Accounting Policies - Estimated Useful Lives for Significant Property and Equipment (Details)	12 Months Ended
	Dec. 31, 2020
Purchased software, including capitalized software development costs
Property, Plant and Equipment [Line Items]
Estimated useful life	3 years
Computer hardware
Property, Plant and Equipment [Line Items]
Estimated useful life	3 years
Minimum | Furniture and office equipment
Property, Plant and Equipment [Line Items]
Estimated useful life	3 years
Maximum | Furniture and office equipment
Property, Plant and Equipment [Line Items]
Estimated useful life	5 years

Significant Accounting Polic_10

Significant Accounting Policies - Estimated Useful Lives Used in Computing Amortization (Detail)	12 Months Ended
	Dec. 31, 2020
Customer relationships
Finite-Lived Intangible Assets [Line Items]
Estimated useful life of intangible asset	7 years
Acquired technology
Finite-Lived Intangible Assets [Line Items]
Estimated useful life of intangible asset	7 years

Property and Equipment - Summar

Property and Equipment - Summary of Property and Equipment (Details) - USD ($) $ in Thousands	Dec. 31, 2020	Dec. 31, 2019
Property, Plant and Equipment [Line Items]
Property and equipment, gross	$ 36,648	$ 32,599
Less: accumulated depreciation	(27,941)	(23,002)
Property and equipment, net	8,707	9,597
Purchased software, including capitalized software development costs
Property, Plant and Equipment [Line Items]
Property and equipment, gross	17,303	13,965
Computer hardware
Property, Plant and Equipment [Line Items]
Property and equipment, gross	9,541	8,975
Furniture and office equipment
Property, Plant and Equipment [Line Items]
Property and equipment, gross	2,388	2,369
Leasehold improvements
Property, Plant and Equipment [Line Items]
Property and equipment, gross	7,368	7,244
Construction in process
Property, Plant and Equipment [Line Items]
Property and equipment, gross	$ 48	$ 46

Property and Equipment - Additi

Property and Equipment - Additional Information (Details) - USD ($) $ in Millions	12 Months Ended
	Dec. 31, 2020	Dec. 31, 2019	Dec. 31, 2018
Property, Plant and Equipment [Line Items]
Depreciation expense	$ 5.7	$ 5.7	$ 5.5
Loss on disposal of property and equipment		0.4
Computer Hardware, Furniture and Office Equipment and Leasehold Improvements
Property, Plant and Equipment [Line Items]
Disposals	0.8	10	4.9
Accumulated depreciation	$ 0.8	$ 9.6	4.9
Leasehold improvements
Property, Plant and Equipment [Line Items]
Disposals			0.8
Accumulated depreciation			0.3
Lease incentive obligation reduction			$ 0.5

Business Combination, Goodwil_3

Business Combination, Goodwill and Intangible Assets - Additional Information (Details) - USD ($)	Jul. 23, 2020	Dec. 31, 2020	Dec. 31, 2019	Dec. 31, 2018
Business Combination, Separately Recognized Transactions [Line Items]
Goodwill acquired		$ 30,990,000	$ 23,486,000
Change to goodwill in the period			0
Amortization expense		800,000	600,000	$ 600,000
BlueBoard
Business Combination, Separately Recognized Transactions [Line Items]
Cash purchase price	$ 9,000,000
Contingent consideration (up to)	3,000,000
Business combination, contingent consideration, liability	1,500,000	1,330,000	$ 0
Consideration transferred	10,500,000
Goodwill acquired	7,500,000
Identifiable intangible assets acquired	3,700,000
Long-term deferred tax liabilities acquired	600,000
Working capital liability acquired	100,000
Transaction costs incurred		$ 500,000
BlueBoard | Acquired technology
Business Combination, Separately Recognized Transactions [Line Items]
Identifiable intangible assets acquired	3,300,000
BlueBoard | Customer relationships
Business Combination, Separately Recognized Transactions [Line Items]
Identifiable intangible assets acquired	$ 400,000

Business Combination,, Goodwill

Business Combination,, Goodwill and Intangible Assets - Schedule of Goodwill (Details) $ in Thousands	12 Months Ended
	Dec. 31, 2020USD ($)
Goodwill and Intangible Assets Disclosure [Abstract]
Balance as of December 31, 2019	$ 23,486
Goodwill attributable to the BlueBoard acquisition	7,504
Balance as of December 31, 2020	$ 30,990

Business Combination, Goodwil_4

Business Combination, Goodwill and Intangible Assets - Summary of Intangible Assets (Details) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2020	Dec. 31, 2019
Finite-Lived Intangible Assets [Line Items]
Gross Carrying Amount	$ 7,970	$ 4,260
Accumulated Amortization	(3,815)	(2,975)
Net Carrying Amount	$ 4,155	$ 1,285
Weighted Average Useful Life (in years)	7 years	7 years
Customer relationships
Finite-Lived Intangible Assets [Line Items]
Gross Carrying Amount	$ 2,603	$ 2,230
Accumulated Amortization	(1,940)	(1,598)
Net Carrying Amount	$ 663	$ 632
Weighted Average Useful Life (in years)	7 years	7 years
Acquired technology
Finite-Lived Intangible Assets [Line Items]
Gross Carrying Amount	$ 5,367	$ 2,030
Accumulated Amortization	(1,875)	(1,377)
Net Carrying Amount	$ 3,492	$ 653
Weighted Average Useful Life (in years)	7 years	7 years

Business Combination, Goodwil_5

Business Combination, Goodwill and Intangible Assets - Expected Amortization Expense (Details) - USD ($) $ in Thousands	Dec. 31, 2020	Dec. 31, 2019
Goodwill and Intangible Assets Disclosure [Abstract]
2021	$ 1,048
2022	596
2023	596
2024	557
2025	530
Thereafter	828
Net Carrying Amount	$ 4,155	$ 1,285

Leases Components of Lease Expe

Leases Components of Lease Expense (Details) - USD ($) $ in Thousands	12 Months Ended		32 Months Ended
	Dec. 31, 2020	Dec. 31, 2019	Aug. 31, 2022
Lease Assets And Lease Liabilities [Line Items]
Operating lease right of use assets	$ 8,141	$ 11,128
Finance lease assets, included in Property and equipment, net	495	1,917
Total leased assets	8,636	13,045
Long-term operating leases, net of current portion	5,394	9,767
Long-term finance leases, net of current portion	8	27
Total lease liabilities	10,133	15,389
Finance lease, right-of-use asset, accumulated amortization	5,800	4,400
Operating lease cost, included in General and administrative expense	4,093	4,808
Amortization of finance lease assets, included in General and administrative expense	1,421	2,041
Interest on finance lease liabilities, included in Other income (expense), net	35	140
Sublease income, reducing rent expense in General and administrative expense	(167)	(168)
Net lease cost	5,382	6,821
Short-term lease cost	200	400
Sublease income expected of remaining term of agreement	167	168
Forecast [Member]
Lease Assets And Lease Liabilities [Line Items]
Sublease income, reducing rent expense in General and administrative expense			$ (200)
Sublease income expected of remaining term of agreement			$ 200
Other Current Liabilities
Lease Assets And Lease Liabilities [Line Items]
Operating lease liabilities, included in Other current liabilities	4,716	4,177
Finance lease liabilities, included in Other current liabilities	$ 15	$ 1,418

Leases Other Information Relate

Leases Other Information Related To Leases (Details) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2020	Dec. 31, 2019
Leases [Abstract]
Operating Lease, Payments	$ 4,501	$ 4,852
Finance Lease, Interest Payment on Liability	105	216
Finance Lease, Principal Payments	$ 1,422	$ 2,209
Operating Lease, Weighted Average Remaining Lease Term	2 years 2 months 19 days	3 years 2 months 12 days
Finance Lease, Weighted Average Remaining Lease Term	4 months 28 days	1 year 4 months 13 days
Operating Lease, Weighted Average Discount Rate, Percent	5.48%	5.50%
Finance Lease, Weighted Average Discount Rate, Percent	7.12%	7.28%

Leases Maturities of Lease Liab

Leases Maturities of Lease Liabilities (Details) $ in Thousands	Dec. 31, 2020USD ($)
Leases [Abstract]
Operating Leases, 2021	$ 5,130
Operating Leases, 2022	4,360
Operating Leases, 2023	1,236
Operating Leases, Total lease payments	10,726
Operating Leases, Imputed interest	(616)
Operating Leases, Present value of lease liabilities	10,110
Finance Leases, 2021	15
Finance Leases, 2022	8
Finance Leases, 2023	0
Finance Leases, Total lease payments	23
Finance Leases, Imputed interest	0
Finance Leases, Present value of lease liabilities	$ 23

Line of Credit (Details)

Line of Credit (Details) - 2020 Revolving Credit Facility - Line of Credit	Aug. 05, 2020USD ($)
Revolving Credit Facility
Line of Credit Facility [Line Items]
Line of credit facility, maximum borrowing capacity	$ 25,000,000
Debt covenant, maximum increase allowed during term	$ 10,000,000
Line of credit facility, unused capacity, commitment fee percentage	0.50%
Revolving Credit Facility | Base Rate
Line of Credit Facility [Line Items]
Basis spread on variable rate	2.25%
Revolving Credit Facility | London Interbank Offered Rate (LIBOR)
Line of Credit Facility [Line Items]
Basis spread on variable rate	3.25%
Letter of Credit
Line of Credit Facility [Line Items]
Line of credit facility, maximum borrowing capacity	$ 10,000,000
Stated interest rate percentage	3.25%

Revenue from Contracts with C_3

Revenue from Contracts with Customers - Disaggregation of Revenue (Detail) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2020	Dec. 31, 2019	Dec. 31, 2018
Disaggregation of Revenue [Line Items]
Revenue	$ 145,072	$ 129,959	$ 131,218
Retailers
Disaggregation of Revenue [Line Items]
Revenue	87,704	84,316	89,992
Brands
Disaggregation of Revenue [Line Items]
Revenue	47,999	38,470	32,628
Other
Disaggregation of Revenue [Line Items]
Revenue	$ 9,369	$ 7,173	$ 8,598

Revenue from Contracts with C_4

Revenue from Contracts with Customers - Additional Information (Detail) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2020	Jan. 01, 2020	Dec. 31, 2019
Revenue, Initial Application Period Cumulative Effect Transition [Line Items]
Contract period	12 months
Payment period	30 days
Deferred revenue	$ 22,819	$ 20,000	$ 21,000
Capitalized contract cost, amortization period	5 years
Revenues	$ 145,100
Capitalized contract cost, net	$ 21,333		$ 18,414
RetailersBrandsOther [Member]
Revenue, Initial Application Period Cumulative Effect Transition [Line Items]
Contract period	1 year
Prepaid Expenses and Other Current Assets
Revenue, Initial Application Period Cumulative Effect Transition [Line Items]
Capitalized contract cost, net	$ 7,300

Revenue from Contracts with C_5

Revenue from Contracts with Customers - Transaction Price Allocated to Future Performance Obligations (Detail) $ in Millions	12 Months Ended
	Dec. 31, 2020USD ($)
Revenue from Contract with Customer [Abstract]
Contract period	12 months
Remaining performance obligation	$ 30.6
Revenue, Remaining Performance Obligation, Expected Timing of Satisfaction, Start Date [Axis]: 2021-01-01
Revenue from Contract with Customer [Abstract]
Remaining performance obligation	$ 19
Revenue, Remaining Performance Obligation, Expected Timing of Satisfaction [Line Items]
Performance obligation period	12 months

Revenue from Contracts with C_6

Revenue from Contracts with Customers - Deferred Revenue (Detail) $ in Thousands	12 Months Ended
	Dec. 31, 2020USD ($)
Deferred revenue
Balance, beginning of period	$ 21,459
Net additions	109,045
Revenue recognized	(107,203)
Balance, end of period	$ 23,301

Revenue from Contracts with C_7

Revenue from Contracts with Customers - Costs to Obtain Contracts (Detail) $ in Thousands	12 Months Ended
	Dec. 31, 2020USD ($)
Deferred contract costs
Balance, beginning of period	$ 18,414
Additions	8,963
Amortized costs	(6,044)
Balance, end of period	$ 21,333

Income Taxes - Components of In

Income Taxes - Components of Income (Loss) Before Income Taxes (Details) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2020	Dec. 31, 2019	Dec. 31, 2018
Income Tax Disclosure [Abstract]
Domestic	$ 18,176	$ 1,994	$ (10,552)
Foreign	1,092	2,177	3,565
Income (loss) before income taxes	$ 19,268	$ 4,171	$ (6,987)

Income Taxes - Provision for In

Income Taxes - Provision for Income Tax Expense (Details) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2020	Dec. 31, 2019	Dec. 31, 2018
Current:
Federal	$ (10)	$ (10)	$ (20)
State	460	0	0
Foreign	32	168	141
Total	482	158	121
Deferred:
Federal	0	0	(211)
State	3	(18)	12
Foreign	(42)	549	692
Total	(39)	531	493
Total tax expense	$ 443	$ 689	$ 614

Income Taxes - Additional Infor

Income Taxes - Additional Information (Details)	12 Months Ended
	Dec. 31, 2020USD ($)	Dec. 31, 2019USD ($)return	Dec. 31, 2018USD ($)
Operating Loss Carryforwards [Line Items]
Foreign current income tax expense in other comprehensive loss	$ (100,000)	$ 100,000
Deferred income taxes	(39,000)	531,000	$ 493,000
Undistributed earnings of foreign subsidiaries	500,000	0
Undistributed foreign earnings, deferred tax liability			$ 0
Undistributed earnings of foreign subsidiaries	$ 500,000	$ 0
U.S. statutory federal rate	21.00%	21.00%	21.00%
Unrecognized tax benefits that would impact effective tax rate		$ 0
Unrecognized tax benefits, income tax penalties and interest accrued	$ 0	$ 0
Number of income tax returns under examination | return		0
Deferred Tax Assets from Current Operations
Operating Loss Carryforwards [Line Items]
Increase (decrease) in valuation allowance	3.2	$ 400,000
Federal
Operating Loss Carryforwards [Line Items]
Operating loss carryforwards	110,300,000	128,700,000
Tax credit carryforward	5,900,000	5,100,000
State
Operating Loss Carryforwards [Line Items]
Operating loss carryforwards	136,500,000	151,100,000
Foreign
Operating Loss Carryforwards [Line Items]
Operating loss carryforwards	$ 36,600,000	$ 32,300,000

Income Taxes - Components of Ne

Income Taxes - Components of Net Deferred Tax Assets (Liabilities) (Details) - USD ($) $ in Thousands	Dec. 31, 2020	Dec. 31, 2019
Deferred tax assets:
Domestic tax loss carryforwards	$ 27,651	$ 31,974
Foreign tax loss carryforwards	7,596	6,098
Stock-based compensation	3,092	3,129
Tax credits	4,345	3,860
Operating lease liability	2,277	3,121
Other assets	3,010	2,062
Valuation allowance	(35,393)	(38,603)
Total deferred tax assets	12,578	11,641
Deferred tax liabilities:
Fixed assets	1,000	821
Intangible assets	1,395	491
Capitalized contract costs	5,242	4,468
Right of use assets	1,840	2,478
Other liabilities	21	21
Total deferred tax liabilities	9,498	8,279
Net deferred tax asset	$ 3,080	$ 3,362

Income Taxes - Effective Income

Income Taxes - Effective Income Tax Reconciliation (Details)	12 Months Ended
	Dec. 31, 2020	Dec. 31, 2019	Dec. 31, 2018
Income Tax Disclosure [Abstract]
U.S. statutory federal rate	21.00%	21.00%	21.00%
Increase (decrease) resulting from:
State taxes, net of federal benefit	3.90%	3.70%	7.80%
Nondeductible expenses and excludable income	(0.40%)	1.60%	(3.70%)
Effect of foreign tax rate differential	(0.20%)	2.30%	(0.50%)
Uncertain tax positions	1.80%	4.90%	(3.30%)
Research and development credit	(4.80%)	(24.80%)	15.10%
Change in valuation allowance	(17.00%)	(12.00%)	(36.40%)
Expiration of NOL carryforwards	0.70%	4.00%	(1.00%)
Stock-based compensation	(0.90%)	6.40%	(9.80%)
Change in statutory tax rates	(2.30%)	4.00%	0.60%
Other	0.50%	5.40%	1.40%
Effective tax rate	2.30%	16.50%	(8.80%)

Income Taxes - Unrecognized Tax

Income Taxes - Unrecognized Tax Benefits (Details) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2020	Dec. 31, 2019	Dec. 31, 2018
Reconciliation of Unrecognized Tax Benefits
Balance as of January 1	$ 1,601	$ 1,408	$ 1,282
Increases related to current tax positions	281	183	217
Increases related to prior year tax positions	150	20	12
Decreases related to prior year tax positions	(109)	(10)	(103)
Balance as of December 31	$ 1,923	$ 1,601	$ 1,408

Equity Incentive Plans and St_3

Equity Incentive Plans and Stock-Based Compensation - Additional Information (Detail) - USD ($) $ / shares in Units, $ in Millions	Jan. 01, 2021	May 31, 2013	Dec. 31, 2020	Dec. 31, 2019	Dec. 31, 2018
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Percent of executive office equity awards granted as performance-based vesting restricted stock units			50.00%
Share-based Payment Arrangement, Tranche One
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Award vesting rights percentage			50.00%
Share-based Payment Arrangement, Tranche Two
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Award vesting rights percentage			50.00%
Minimum
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Award vesting rights percentage			0.00%
Maximum
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Award vesting rights percentage			150.00%
Stock Options
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Weighted average grant date fair value (in dollars per share)				$ 4.51	$ 5.98
Total fair value of stock options vested during period			$ 1.5	$ 1.8	$ 1.5
Options, compensation cost not yet recognized			$ 0.6
Unrecognized compensation cost related to nonvested awards, weighted-average period recognized			1 year 3 months 18 days
Aggregate intrinsic value of stock options exercised			$ 2.3	$ 0.2	$ 0.6
RSUs
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Unrecognized compensation cost related to nonvested awards, weighted-average period recognized			1 year 9 months 18 days
Nonvested RSUs, compensation cost not yet recognized			$ 9
Performance Shares
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Unrecognized compensation cost related to nonvested awards, weighted-average period recognized			1 year 8 months 12 days
Nonvested RSUs, compensation cost not yet recognized			$ 1.1
2013 Plan
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Number of shares reserved for issuance (in shares)		1,250,000
Common stock reserved for issuance increase, automatic increase, term		10 years
Number of shares reserved for issuance, automatic increase, percent of common stock outstanding of preceding calendar year (in shares)		5.00%
Number of shares available for future grant (in shares)			3,443,894
Subsequent Event | 2013 Plan
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Number of additional shares authorized (in shares)	1,451,021

Equity Incentive Plans and St_4

Equity Incentive Plans and Stock-Based Compensation - Summary of Stock-Based Compensation Expense (Detail) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2020	Dec. 31, 2019	Dec. 31, 2018
Stock-Based Compensation [Line Items]
Share-based compensation expense	$ 10,200	$ 8,976	$ 10,598
Cost of revenue
Stock-Based Compensation [Line Items]
Share-based compensation expense	972	995	911
Sales and marketing
Stock-Based Compensation [Line Items]
Share-based compensation expense	2,792	2,385	3,144
Research and development
Stock-Based Compensation [Line Items]
Share-based compensation expense	2,168	1,898	2,152
General and administrative
Stock-Based Compensation [Line Items]
Share-based compensation expense	$ 4,268	$ 3,698	$ 4,391

Equity Incentive Plans and St_5

Equity Incentive Plans and Stock-Based Compensation - Summary of Weighted-Average Assumptions Used for Estimating Fair Value of Stock Granted (Detail) - Stock Options	12 Months Ended
	Dec. 31, 2019	Dec. 31, 2018
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Expected term (years)	6 years 3 months	6 years 3 months
Expected volatility		43.00%
Dividend yield	0.00%	0.00%
Minimum
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Risk-free interest rate	1.80%	2.70%
Expected volatility	37.00%
Maximum
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Risk-free interest rate	2.50%	2.90%
Expected volatility	41.00%

Equity Incentive Plans and St_6

Equity Incentive Plans and Stock-Based Compensation - Summary of Stock Option Activity (Detail) $ / shares in Units, $ in Thousands	12 Months Ended
	Dec. 31, 2020USD ($)$ / sharesshares
Number of Options
Outstanding beginning of period (in shares) | shares	2,196,766
Granted (in shares) | shares	0
Exercised (in shares) | shares	(440,174)
Forfeited (in shares) | shares	(5,355)
Expired (in shares) | shares	(47,992)
Outstanding end of period (in shares) | shares	1,703,245
Exercisable (in shares) | shares	1,189,509
Vested and expected to vest (in shares) | shares	1,594,971
Weighted Average Exercise Price
Outstanding beginning of period (in dollars per share) | $ / shares	$ 10.47
Granted (in dollars per share) | $ / shares	0
Exercised (in dollars per share) | $ / shares	8.69
Forfeited (in dollars per share) | $ / shares	11.60
Expired (in dollars per share) | $ / shares	12.38
Outstanding end of period (in dollars per share) | $ / shares	10.87
Exercisable (in dollars per share) | $ / shares	10.38
Vested and expected to vest (in dollars per share) | $ / shares	$ 10.80
Weighted Average Remaining Contractual Term
Outstanding	5 years 8 months 8 days
Exercisable	4 years 9 months 18 days
Vested and expected to vest	5 years 6 months 18 days
Aggregate Intrinsic Value
Ending balance | $	$ 9,160
Exercisable | $	7,122
Vested and expected to vest | $	$ 8,727

Equity Incentive Plans and St_7

Equity Incentive Plans and Stock-Based Compensation - Summary of Restricted Stock Units Activity (Detail)	12 Months Ended
	Dec. 31, 2020$ / sharesshares
RSUs
Number of RSUs
Unvested RSUs as of beginning of period (in shares) | shares	2,086,646
Granted (in shares) | shares	958,055
Vested (in shares) | shares	(743,730)
Forfeited (in shares) | shares	(240,143)
Unvested RSUs as of end of period (in shares) | shares	2,060,828
Weighted average grant date fair value
Unvested RSU's as of beginning of period (in dollars per share) | $ / shares	$ 10.93
Granted (in dollars per share) | $ / shares	11.32
Vested (in dollars per share) | $ / shares	11.21
Forfeited (in dollars per share) | $ / shares	10.36
Unvested RSU's as of end of period (in dollars per share) | $ / shares	$ 11.08
Performance Shares
Number of RSUs
Unvested RSUs as of beginning of period (in shares) | shares	0
Granted (in shares) | shares	142,317
Vested (in shares) | shares	0
Forfeited (in shares) | shares	0
Unvested RSUs as of end of period (in shares) | shares	142,317
Weighted average grant date fair value
Unvested RSU's as of beginning of period (in dollars per share) | $ / shares	$ 0
Granted (in dollars per share) | $ / shares	9.27
Vested (in dollars per share) | $ / shares	0
Forfeited (in dollars per share) | $ / shares	0
Unvested RSU's as of end of period (in dollars per share) | $ / shares	$ 9.27

Net Income (Loss) Per Share Net

Net Income (Loss) Per Share Net Income (Loss) Per Share - Schedule of Earnings Per Share, Basic and Diluted (Details) - USD ($)	12 Months Ended
	Dec. 31, 2020	Dec. 31, 2019	Dec. 31, 2018
Earnings Per Share, Diluted, by Common Class, Including Two Class Method [Line Items]
Net income (loss)	$ 18,825,000	$ 3,482,000	$ (7,601,000)
Weighted average common shares outstanding, basic	28,616,401	27,886,278	27,138,274
Basic (in dollars per share)	$ 0.66	$ 0.12	$ (0.28)
Weighted average common shares outstanding, diluted	30,035,261	28,816,977	27,138,274
Diluted (in dollars per share)	$ 0.63	$ 0.12	$ (0.28)
Stock Options
Earnings Per Share, Diluted, by Common Class, Including Two Class Method [Line Items]
Incremental Common Shares Attributable to Dilutive Effect of Share-based Payment Arrangements	383,607	167,208	0
RSUs
Earnings Per Share, Diluted, by Common Class, Including Two Class Method [Line Items]
Incremental Common Shares Attributable to Dilutive Effect of Share-based Payment Arrangements	1,035,253	763,491	0

Net Income (Loss) Per Share - S

Net Income (Loss) Per Share - Schedule of Securities Excluded from Calculation of Weighted Average Common Shares Outstanding (Detail) - shares	12 Months Ended
	Dec. 31, 2020	Dec. 31, 2019	Dec. 31, 2018
Stock options
Antidilutive Securities Excluded from Computation of Earnings Per Share [Line Items]
Antidilutive securities excluded from calculation of weighted average common shares outstanding (in shares)	437,927	1,626,757	2,208,141
RSUs
Antidilutive Securities Excluded from Computation of Earnings Per Share [Line Items]
Antidilutive securities excluded from calculation of weighted average common shares outstanding (in shares)	60,674	278,937	2,216,430

Restructuring (Details)

Restructuring (Details) $ in Thousands	12 Months Ended
	Dec. 31, 2019USD ($)
Restructuring Cost and Reserve [Line Items]
Reduction in global workforce, percent	10.00%
Severance costs	$ 1,429
Cost of revenue
Restructuring Cost and Reserve [Line Items]
Severance costs	238
Sales and marketing
Restructuring Cost and Reserve [Line Items]
Severance costs	369
Research and development
Restructuring Cost and Reserve [Line Items]
Severance costs	142
General and administrative
Restructuring Cost and Reserve [Line Items]
Severance costs	560
Other (expense) income, net
Restructuring Cost and Reserve [Line Items]
Severance costs	$ 120

Segment and Geographic Inform_3

Segment and Geographic Information - Summary of Revenue by Geography (Detail) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2020	Dec. 31, 2019	Dec. 31, 2018
Revenue by Geography
Revenue	$ 145,072	$ 129,959	$ 131,218
Domestic
Revenue by Geography
Revenue	108,556	97,111	100,442
International
Revenue by Geography
Revenue	$ 36,516	$ 32,848	$ 30,776

Segment and Geographic Inform_4

Segment and Geographic Information - Summary of Revenue by Product (Details) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2020	Dec. 31, 2019	Dec. 31, 2018
Revenue by Product
Revenue	$ 145,072	$ 129,959	$ 131,218
Marketplaces
Revenue by Product
Revenue	107,425	95,757	96,321
Digital Marketing
Revenue by Product
Revenue	21,424	19,683	18,919
Other Products
Revenue by Product
Revenue	$ 16,223	$ 14,519	$ 15,978

Segment and Geographic Inform_5

Segment and Geographic Information - Additional Information (Detail) $ in Thousands	12 Months Ended
	Dec. 31, 2020USD ($)segment	Dec. 31, 2019USD ($)	Dec. 31, 2018USD ($)
Segment Reporting [Abstract]
Number of reportable segments | segment	1
Number of operating segments | segment	1
Revenues from External Customers and Long-Lived Assets [Line Items]
Revenue | $	$ 145,072	$ 129,959	$ 131,218
United Kingdom
Revenues from External Customers and Long-Lived Assets [Line Items]
Revenue | $	$ 12,500	$ 13,000	$ 12,300

Retirement Plans (Details)

Retirement Plans (Details) - USD ($) $ in Millions	12 Months Ended
	Dec. 31, 2020	Dec. 31, 2019	Dec. 31, 2018
Retirement Benefits [Abstract]
Employer contributions	$ 1.9	$ 1.7	$ 1.7

Uncategorized Items - ecom-2020

Label	Element	Value
Cumulative Effect of New Accounting Principle in Period of Adoption	us-gaap_CumulativeEffectOfNewAccountingPrincipleInPeriodOfAdoption	$ 7,501,000
Cumulative Effect of New Accounting Principle in Period of Adoption	us-gaap_CumulativeEffectOfNewAccountingPrincipleInPeriodOfAdoption	240,000
Retained Earnings [Member]
Cumulative Effect of New Accounting Principle in Period of Adoption	us-gaap_CumulativeEffectOfNewAccountingPrincipleInPeriodOfAdoption	7,501,000	[1]
Cumulative Effect of New Accounting Principle in Period of Adoption	us-gaap_CumulativeEffectOfNewAccountingPrincipleInPeriodOfAdoption	$ 240,000	[2]
[1]	The Company recorded a reduction to accumulated deficit at January 1, 2018 as a result of its adoption of Accounting Standards Update No. 2014-09, Revenue from Contracts with Customers (Topic 606).
[2]	The Company recorded a reduction to accumulated deficit at January 1, 2020 as a result of its adoption of Accounting Standards Update No. 2016-13, Financial Instruments - Credit Losses (Topic 326).