MaxPoint Interactive (MXPT) 10-K 8 Mar 17 2016 FY Annual report Financial data

Document and Entity Information

Document and Entity Information - USD ($) $ in Millions	12 Months Ended
	Dec. 31, 2016	Mar. 01, 2017	Jun. 30, 2016
Document And Entity Information
Entity Registrant Name	MAXPOINT INTERACTIVE, INC.
Entity Central Index Key	1,611,231
Current Fiscal Year End Date	--12-31
Entity Filer Category	Non-accelerated Filer
Document Type	10-K
Document Period End Date	Dec. 31, 2016
Document Fiscal Year Focus	2,016
Document Fiscal Period Focus	FY
Amendment Flag	false
Entity Common Stock, Shares Outstanding		6,632,889
Entity Current Reporting Status	Yes
Entity Well-known Seasoned Issuer	No
Entity Voluntary Filers	No
Entity Public Float			$ 22.8

Consolidated Balance Sheets

Consolidated Balance Sheets - USD ($) $ in Thousands	Dec. 31, 2016	Dec. 31, 2015
Current assets:
Cash and cash equivalents	$ 24,221	$ 41,143
Accounts receivable, net	43,432	43,336
Prepaid expenses and other current assets	1,477	1,246
Restricted cash, short-term	0	1,861
Total current assets	69,130	87,586
Property, equipment and software, net	20,125	19,385
Other long-term assets	60	315
Total assets	89,315	107,286
Current liabilities:
Accounts payable	12,660	14,987
Accrued expenses and other current liabilities	9,400	8,386
Short-term debt	27,489	31,225
Total current liabilities	49,549	54,598
Other long-term liabilities	1,218	955
Total liabilities	50,767	55,553
Commitments and contingencies
Stockholders’ equity:
Common stock, $0.00005 par value; 500,000,000 shares authorized, 6,560,987 and 6,632,889 shares issued and outstanding as of December 31, 2015 and 2016, respectively	1	1
Additional paid-in capital	107,898	103,114
Accumulated other comprehensive loss	(200)	(82)
Accumulated deficit	(69,151)	(51,300)
Total stockholders’ equity	38,548	51,733
Total liabilities and stockholders’ equity	$ 89,315	$ 107,286

Consolidated Balance Sheets (Pa

Consolidated Balance Sheets (Parenthetical) - $ / shares	Dec. 31, 2016	Dec. 31, 2015
Common stock
Common shares par value (in usd per share)	$ 0.00005	$ 0.00005
Common shares authorized	500,000,000	500,000,000
Common shares issued	6,632,889	6,560,987
Common shares outstanding	6,632,889	6,560,987

Consolidated Statements of Oper

Consolidated Statements of Operations - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2016	Dec. 31, 2015	Dec. 31, 2014
Income Statement [Abstract]
Revenue	$ 149,109	$ 140,127	$ 106,460
Traffic acquisition costs	51,120	53,799	44,534
Other cost of revenue	19,936	14,881	8,283
Gross profit	78,053	71,447	53,643
Operating expenses:
Sales and marketing	49,812	52,718	38,472
Research and development	26,576	23,444	14,656
General and administrative	18,476	15,666	11,318
Total operating expenses	94,864	91,828	64,446
Loss from operations	(16,811)	(20,381)	(10,803)
Other expense (income):
Interest expense	987	1,250	1,315
Interest income	(3)	0	0
Amortization and write-off of debt discount	0	1,108	170
Amortization and write-off of deferred financing costs	56	197	32
Derivative fair value adjustment related to common stock warrants	0	(482)	671
Other income	0	(1)	(2)
Total other expense	1,040	2,072	2,186
Loss before income taxes	(17,851)	(22,453)	(12,989)
Provision for income taxes	0	0	0
Net loss	$ (17,851)	$ (22,453)	$ (12,989)
Net loss per basic and diluted share of common stock (in usd per share)	$ (2.71)	$ (4.12)	$ (13.25)
Weighted-average shares used to compute net loss per basic and diluted share of common stock (in shares)	6,592,424	5,452,231	980,351

Consolidated Statements of Comp

Consolidated Statements of Comprehensive Loss - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2016	Dec. 31, 2015	Dec. 31, 2014
Statement of Comprehensive Income [Abstract]
Net loss	$ (17,851)	$ (22,453)	$ (12,989)
Other comprehensive loss:
Foreign currency translation adjustments	(118)	(38)	(44)
Comprehensive loss	$ (17,969)	$ (22,491)	$ (13,033)

Consolidated Statements of Chan

Consolidated Statements of Changes in Stockholders’ (Deficit) Equity - USD ($) $ in Thousands	Total	Common Stock	Additional Paid-in Capital	Accumulated Other Comprehensive Loss	Accumulated Deficit
Balance - beginning of period ( in shares) at Dec. 31, 2013		940,163
Balance - beginning of period at Dec. 31, 2013	$ (13,612)	$ 0	$ 2,246	$ 0	$ (15,858)
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Conversion of convertible preferred stock to common stock	0
Exercise of stock options ( in shares)		114,191
Exercise of stock options	606		606
Stock-based compensation	1,878		1,878
Warrant derivative liability reclassified to additional paid-in capital	0
Liability-based option awards reclassified to additional paid-in capital	0
Vesting of restricted stock subject to repurchase	2		2
Foreign currency translation adjustments	(44)			(44)
Net loss	(12,989)				(12,989)
Balance - end of period ( in shares) at Dec. 31, 2014		1,054,354
Balance - end of period at Dec. 31, 2014	(24,159)	$ 0	4,732	(44)	(28,847)
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Issuance of common stock from initial public offering, net of issuance costs (in shares)		1,625,000
Issuance of common stock from initial public offering, net of issuance costs	65,736		65,736
Conversion of convertible preferred stock to common stock (in shares)		3,712,206
Conversion of convertible preferred stock to common stock	25,476	$ 1	25,475
Exercise of stock options ( in shares)		135,995
Exercise of stock options	781		781
Issuance of common stock under employee stock purchase plan (in shares)		33,432
Issuance of common stock under employee stock purchase plan	548		548
Stock-based compensation	4,030		4,030
Issuance of common stock warrant	335		335
Warrant derivative liability reclassified to additional paid-in capital	1,132		1,132
Liability-based option awards reclassified to additional paid-in capital	288		288
Vesting of restricted stock subject to repurchase	57		57
Foreign currency translation adjustments	(38)			(38)
Net loss	$ (22,453)				(22,453)
Balance - end of period ( in shares) at Dec. 31, 2015	6,560,987	6,560,987
Balance - end of period at Dec. 31, 2015	$ 51,733	$ 1	103,114	(82)	(51,300)
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Conversion of convertible preferred stock to common stock	$ 0
Exercise of stock options ( in shares)	31,125	31,125
Exercise of stock options	$ 113		113
Issuance of common stock under employee stock purchase plan (in shares)		55,995
Issuance of common stock under employee stock purchase plan	387		387
Stock-based compensation	4,409		4,409
Warrant derivative liability reclassified to additional paid-in capital	0
Liability-based option awards reclassified to additional paid-in capital	0
Vesting of restricted stock subject to repurchase	0
Repurchases of common stock (in shares)		(15,197)
Repurchases of common stock	(125)		(125)
Extinguishment of fractional shares resulting from reverse stock split (in shares)		(21)
Extinguishment of fractional shares resulting from reverse stock split	0
Foreign currency translation adjustments	(118)			(118)
Net loss	$ (17,851)				(17,851)
Balance - end of period ( in shares) at Dec. 31, 2016	6,632,889	6,632,889
Balance - end of period at Dec. 31, 2016	$ 38,548	$ 1	$ 107,898	$ (200)	$ (69,151)

Consolidated Statements of Cash

Consolidated Statements of Cash Flows - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2016	Dec. 31, 2015	Dec. 31, 2014
Cash flows from operating activities:
Net loss	$ (17,851)	$ (22,453)	$ (12,989)
Adjustments to reconcile net loss to net cash used in operating activities:
Depreciation and amortization	9,799	6,074	3,071
Stock-based compensation expense	3,906	3,522	2,339
Change in fair value of warrants	0	(482)	671
Bad debt expense	358	205	(211)
Loss on disposal of asset	5	0	0
Amortization and write-off of debt discount	0	1,108	170
Amortization and write-off of deferred financing costs	56	197	32
Changes in operating assets and liabilities:
Accounts receivable	(517)	(2,259)	(16,880)
Prepaid expenses and other current assets	(211)	(429)	(400)
Security deposits	57	(229)	(6)
Accounts payable	(2,761)	(2,544)	8,236
Accrued expenses and other current liabilities	1,046	1,897	2,671
Other long-term liabilities	263	714	239
Net cash used in operating activities	(5,850)	(14,679)	(13,057)
Cash flows from investing activities:
Purchases of property, equipment and software	(2,720)	(8,764)	(3,822)
Capitalized internal-use software costs	(6,689)	(6,195)	(3,992)
Changes to restricted cash	1,861	3,039	(1,100)
Net cash used in investing activities	(7,548)	(11,920)	(8,914)
Cash flows from financing activities:
Proceeds from the issuance of common stock in initial public offering, net of underwriting discounts and commissions	0	69,518	0
Payments of costs related to initial public offering	0	(2,304)	(1,478)
Proceeds from debt	42,300	13,825	58,316
Repayment of debt	(46,036)	(27,500)	(31,177)
Proceeds from stock option exercises	113	781	606
Proceeds from issuance of common stock under employee stock purchase plan	387	548	0
Payments for repurchases of common stock	(125)	0	0
Payments of issuance costs related to debt	(110)	(57)	(189)
Proceeds from unvested stock option exercises	0	0	57
Net cash provided by (used in) financing activities	(3,471)	54,811	26,135
Effect of exchange rate changes on cash and cash equivalents	(53)	(18)	(20)
Net increase (decrease) in cash and cash equivalents	(16,922)	28,194	4,144
Cash and cash equivalents at beginning of period	41,143	12,949	8,805
Cash and cash equivalents at end of period	24,221	41,143	12,949
Supplemental disclosures of other cash flow information:
Cash paid for interest	1,050	1,481	1,249
Supplemental disclosures of non-cash investing and financing activities:
Purchases of property, equipment and software included in accounts payable and accruals	520	59	536
Additions to property, equipment and software from other long-term assets	213	0	0
Stock-based compensation capitalized in internal-use software costs	503	335	0
Vesting of restricted stock subject to repurchase	0	57	2
Issuance of lender warrants allocated to debt discount	0	335	943
Conversion of convertible preferred stock to common stock	0	25,476	0
Warrant derivative liability reclassified to additional paid-in capital	0	1,132	0
Liability-based option awards reclassified to additional paid-in capital	0	288	0
Deferred offering costs included in accounts payable and accruals	0	0	1,367
Deferred offering costs reclassified to additional paid-in capital	$ 0	$ 3,782	$ 0

Description of Business

Description of Business	12 Months Ended
	Dec. 31, 2016
Organization, Consolidation and Presentation of Financial Statements [Abstract]
Description of Business	Description of Business Organization MaxPoint Interactive, Inc. (the “Company”) was incorporated in September 2006 under the state laws of Delaware. The Company is a provider of a business intelligence and marketing automation solution. The Company’s customers are located in the United States and Europe and consist primarily of enterprises with national brands in the consumer products, retail, automotive, financial services, healthcare, telecommunications and entertainment industries. The Company’s MaxPoint Intelligence Platform predicts the most likely local buyers of a specific product at a particular retail location and then executes cross-channel digital marketing campaigns to reach these buyers on behalf of the Company’s customers. The Company is headquartered in Morrisville, North Carolina and has offices across the United States and one in the United Kingdom. Initial Public Offering On March 11, 2015 (the “Closing Date”), the Company completed an initial public offering (“IPO”) of its common stock. The Company sold an aggregate of 1,625,000 shares of common stock under a registration statement on Form S-1, declared effective on March 5, 2015 (the “Effective Date”), at a public offering price of $46.00 per share. Net proceeds to the Company were $69.5 million , after deducting underwriting discounts and commissions, and before deducting offering expenses of $3.8 million . Upon the completion of the IPO, all outstanding shares of the Company’s convertible preferred stock were converted into an aggregate of 3,712,206 shares of common stock. Reverse Stock Split Prior to the Company’s IPO, on February 20, 2015 , the Company amended its amended and restated certificate of incorporation effecting a 1-for-2 reverse stock split of its capital stock. The reverse stock split adjusted the authorized shares of capital stock, but did not cause an adjustment to the par value. As a result of the reverse stock split, the Company was required to adjust the share amounts under its equity incentive plan and common stock warrant agreements with third parties. Subsequent to the Company’s IPO, on April 25, 2016, the Company amended its amended and restated certificate of incorporation effecting a 1-for-4 reverse stock split of its outstanding shares of capital stock. The reverse stock split did not change the number of authorized shares of capital stock of the Company or cause an adjustment to the par value of the Company’s capital stock. As a result of the reverse stock split, the Company was required to adjust the share amounts under its equity incentive plans and common stock warrant agreements with third parties. No fractional shares were issued in connection with the reverse stock split. Stockholders who would have otherwise held a fractional share of capital stock received a cash payment for any fractional share resulting from the split in an amount equal to such fraction multiplied by the closing sales price of the common stock as reported on the New York Stock Exchange on April 25, 2016, the last trading day immediately prior to the split. All disclosures of shares and per share data in the consolidated financial statements and related notes have been adjusted to reflect the reverse stock split for all periods presented. Stock Exchange Listing Transfer On May 2, 2016, the Company provided written notice to the New York Stock Exchange of its intention to voluntarily delist its common stock on the New York Stock Exchange and to list its common stock on the Nasdaq Global Market (“Nasdaq”). The common stock was approved for listing on Nasdaq, with its continued trading under the symbol “MXPT.” Trading of the Company’s common stock commenced on Nasdaq on May 13, 2016. Stock Repurchase Program On March 4, 2016 , the Company’s board of directors authorized the repurchase of up to $4.0 million of the Company’s outstanding shares of common stock. As part of the share repurchase program, shares may be purchased in open market transactions, including through block purchases, through privately negotiated transactions, or pursuant to any trading plan that may be adopted in accordance with Rule 10b5-1 of the Securities Exchange Act of 1934, as amended. The stock repurchase program requires that the Company retire repurchased shares in accordance with Delaware corporate law and that such repurchased shares resume the status of authorized but unissued shares of common stock. The Company accounts for stock repurchases using the constructive retirement method wherein the aggregate par value of the stock is recorded to common stock and the excess of cost over par value is recorded to additional paid-in capital, subject to its pro rata portion. For the year ended December 31, 2016, the Company repurchased 15,197 shares under this program at a weighted-average price per share of $8.19 . As of December 31, 2016 the Company had the ability to repurchase up to approximately $3.9 million of common stock under the program.

Summary of Significant Accounti

Summary of Significant Accounting Policies	12 Months Ended
	Dec. 31, 2016
Accounting Policies [Abstract]
Summary of Significant Accounting Policies	Summary of Significant Accounting Policies Principles of Consolidation The consolidated financial statements include the accounts of the Company and its wholly-owned subsidiary and have been prepared in accordance with accounting principles generally accepted in the United States of America (“GAAP”). All intercompany accounts and transactions have been eliminated in consolidation. Basis of Presentation The consolidated financial statements have been prepared on a going concern basis, which contemplates the realization of assets and the satisfaction of liabilities in the normal course of business. Management has evaluated whether there is substantial doubt about the entity’s ability to continue as a going concern. Substantial doubt about an entity’s ability to continue as a going concern exists when conditions and events, considered in the aggregate, indicate that it is probable that the entity will be unable to meet its obligations as they become due within one year after the date the financial statements are issued. Management’s evaluation shall be based on relevant conditions and events that are known and reasonably knowable as of that date. This evaluation initially does not take into consideration the potential mitigating effect of management’s plans that have not been fully implemented as of the date the financial statements are issued. The Company’s management has evaluated the facts and circumstances, excluding consideration of actions that have not been fully implemented as of the date these financial statements are issued, and has concluded that the maturity of its short-term debt raises substantial doubt about its ability to continue as a going concern. The Company’s line of credit requires it to comply with certain covenants as described in Note 6 and has a current maturity date of December 31, 2017. If the Company were required to repay this short-term credit facility at maturity, the impact to the Company’s ability to meet its obligations as they become due would be materially and adversely affected. Management’s plan to mitigate this risk is to amend its current revolving line of credit facility, as it did in March 2016 and September 2016, or to replace it with a suitable alternative prior to its maturity date. The Company believes that its existing cash balances, together with its current revolving line of credit, as amended or replaced, will be sufficient to meet its anticipated cash requirements through at least the next 12 months and that this plan alleviates any substantial doubt about the entity’s ability to continue as a going concern. Use of Estimates The preparation of financial statements in conformity with GAAP requires management to make estimates and assumptions that affect the reported amounts in the consolidated financial statements and accompanying notes. The Company evaluates its estimates, including those related to its allowance for doubtful accounts, revenue recognition, internal-use software, stock-based compensation, income taxes and related valuation allowances and the fair value of common stock warrants. The Company bases its estimates on its 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. Actual results could differ from those estimates. Cash and Cash Equivalents The Company considers all highly liquid investments with a maturity of three months or less when purchased to be cash equivalents. Cash and cash equivalents consist of cash maintained in operating accounts. Restricted Cash Restricted cash represents cash that is subject to contractual withdrawal restrictions and penalties. Restricted cash is classified within the consolidated balance sheets based on the timing of when the restrictions are expected to lapse. The Company presented restricted cash related to its debt agreement in the consolidated balance sheets based on timing of maturity. In accordance with a new loan and security agreement (the “New Loan and Security Agreement”) entered into in June 2014 and described in Note 6, the Company was required to maintain, at all times, $5.0 million , consisting of the sum of: (i) cash held at the lender (determined in accordance with the New Loan and Security Agreement); plus (ii) the unused availability amount on its revolving line of credit; plus (iii) the undrawn portion of an advance related to a term loan and security agreement (the “Mezzanine Loan and Security Agreement”). The Company recorded $1.9 million of restricted cash as of December 31, 2015 based on its availability under the New Loan and Security Agreement of $3.1 million as of that date. On March 8, 2016, the Company amended its new loan and security agreement. As described in Note 6, this amendment removed the $5.0 million minimum cash and availability requirement, among other things. As such, no amounts were reflected as restricted cash within the consolidated balance sheets as of December 31, 2016 . Concentration of Credit Risk Financial instruments that potentially subject the Company to concentrations of credit risk consist principally of cash, cash equivalents and accounts receivable. All of the Company’s cash and cash equivalents are held at financial institutions that management believes to be of high credit quality. The Company’s cash and cash equivalent accounts exceed federally insured limits. The Company has not experienced any losses on cash and cash equivalents to date. To manage accounts receivable risk, the Company evaluates and monitors the creditworthiness of its customers. As of December 31, 2015 , the Company did not have any advertising agencies or customers that individually comprised a significant concentration of its accounts receivable. As of December 31, 2016 , the Company did not have any advertising agencies that individually comprised a significant concentration of its accounts receivable and had one customer that comprised approximately 12% of its accounts receivable. For the years ended December 31, 2014 , 2015 and 2016 , the Company did not have any customers that individually comprised a significant concentration of its revenue. Allowance for Doubtful Accounts The Company extends credit to its customers without requiring collateral. Accounts receivable are stated at net realizable value. The Company utilizes the allowance method to provide for doubtful accounts based on management’s evaluation of the collectability of amounts due. The Company’s estimate is based on historical collection experience and the current status of accounts receivable. Historically, actual write-offs for uncollectible accounts have not significantly differed from the Company’s estimates. At December 31, 2015 and 2016 , the Company had reserved for $0.1 million and $0.3 million of its accounts receivable balance, respectively. The following table presents the changes in the allowance for doubtful accounts for the years ended December 31 (in thousands): 2014 2015 2016 Allowance for doubtful accounts: Balance, beginning of period $ 716 $ 179 $ 102 Add: adjustment for bad debts (211 ) 205 358 Less: write-offs, net of recoveries (326 ) (282 ) (170 ) Balance, end of period $ 179 $ 102 $ 290 Internal-Use Software Development Costs The Company capitalizes certain costs associated with software developed for internal use, primarily consisting of direct labor costs associated with creating the software. Software development projects generally include three stages: the preliminary project stage (all costs are expensed as incurred); the application development stage (certain costs are capitalized and certain costs are expensed as incurred); and the post-implementation/operation stage (all costs are expensed as incurred). Costs capitalized in the application development stage primarily include costs of designing, coding and testing the software. Capitalization of costs requires judgment in determining when a project has reached the application development stage and the period over which the Company expects to benefit from the use of that software. Once the software is placed in service, these capitalized costs are amortized using the straight-line method over the estimated useful life of the software. Internal-use software development costs of $4.0 million , $6.5 million and $7.2 million were capitalized during the years ended December 31, 2014 , 2015 and 2016 , respectively. Capitalized internal-use software development costs are included in property, equipment and software, net in the consolidated balance sheets. Amortization expense related to the capitalized internal-use software was $1.3 million , $2.4 million and $5.0 million for the years ended December 31, 2014 , 2015 and 2016 , respectively, and is primarily included in other cost of revenue and research and development expense in the consolidated statements of operations. The net book value of capitalized internal-use software was $9.8 million and $12.0 million at December 31, 2015 and 2016 , respectively. Property, Equipment and Software, Net Property, equipment and software is recorded at cost, net of depreciation. Expenditures for major additions and improvements are capitalized. Depreciation and amortization are recognized over the estimated useful life of the related assets using the straight-line method. The depreciation and amortization periods for the Company’s significant property, equipment and software categories are as follows: Capitalized internal-use software costs 3 years Computer hardware and software 3 years Furniture and office equipment 3 years Leasehold improvements Lesser of remaining lease term or useful life Repairs and maintenance costs are expensed as incurred. 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 a 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. No impairment charges were necessary for any period presented. Fair Value of Financial Instruments The carrying amounts of certain of the Company’s financial instruments, including cash and cash equivalents, restricted cash, accounts receivable, other current assets, accounts payable and accrued expenses and other current liabilities, approximate their respective fair values due to their short term nature. Foreign Currency Translation and Transactions The consolidated financial statements of the Company’s foreign subsidiary are measured using the local currency as the functional currency. Assets and liabilities of foreign subsidiaries are translated at exchange rates in effect as of the balance sheet date. Revenues and expenses are translated at average exchange rates in effect during the period. Translation adjustments are recorded within accumulated other comprehensive loss, a separate component of stockholders’ equity, in the consolidated balance sheets. Foreign exchange transaction gains and losses have not been material to the Company’s consolidated financial statements for all periods presented. Revenue Recognition The Company generates revenue by delivering targeted advertising campaigns for customers through various channels, including display, mobile and video. The Company recognizes revenue when there is persuasive evidence of an arrangement, delivery has occurred or services have been provided, fees are fixed or determinable, and collection of fees is reasonably assured. Revenue arrangements are evidenced by a fully executed insertion order (“IO”). The IOs specify the delivery terms including the advertising format, the contracted number of advertising impressions to be delivered, the agreed upon rate for each delivered impression, generally on a cost-per-thousand basis, and the fixed period of time for delivery. The IOs typically have a term of less than three months and are cancelable at any time. The Company recognizes revenue in the period in which the impressions are served, limited to the contracted number of impressions as specified in the IO. The Company determines collectability by performing a credit evaluation for new customers and by monitoring its existing customers’ accounts receivable balances. The Company does not typically receive upfront payments from its customers. In the normal course of business, the Company contracts either directly with advertisers or advertising agencies on behalf of their advertiser clients. The determination of whether revenue should be reported on a gross or net basis is based on an assessment of whether the Company is acting as the principal or an agent in the transaction. In determining whether the Company acts as the principal or an agent, the Company follows the accounting guidance for principal-agent considerations. While no one factor is determined to be individually conclusive, indicators that an entity is acting as a principal include if the Company (i) is the primary obligor in the arrangement; (ii) has certain inventory risk; (iii) has latitude in establishing pricing; (iv) adds meaningful value to the service; (v) has discretion in supplier selection; (vi) is involved in the determination of the service specifications; or (vii) has credit risk. The Company recognizes revenue on a gross basis primarily based on the Company’s determination that it is subject to the risk of fluctuating costs from its media vendors, has latitude in establishing prices with its customers, has discretion in selecting media vendors when fulfilling a customer’s advertising campaign, and has credit risk. The Company may enter into multiple element arrangements for the delivery of more than one advertising placement to be delivered at the same time, or within close proximity of one another. When entering into an arrangement that includes multiple elements, the Company determines whether the arrangement should be divided into separate units of accounting and how the arrangement consideration should be measured and allocated among the separate units of accounting. An element qualifies as a separate unit of accounting when the delivered element has standalone value to the customer. The Company sells advertising placements on a standalone basis and thus has determined that each advertising placement in multiple element arrangements represents a separate unit of accounting. The Company allocates arrangement consideration in multiple element arrangements at the inception of an arrangement to all deliverables based on the relative selling price method in accordance with the selling price hierarchy, which includes: (1) vendor-specific objective evidence (“VSOE”), if available; (2) third-party evidence (“TPE”), if VSOE is not available; and (3) best estimate of selling price (“BESP”), if neither VSOE nor TPE is available. The Company has been unable to establish VSOE or TPE, and therefore, uses BESP in its allocation of arrangement consideration. The Company determines BESP for its deliverables by considering a number of factors including, but not limited to, the price lists used by the Company’s sales team in pricing negotiations, historical average and median pricing achieved in prior contractual customer arrangements and input from the Company’s sales operation department regarding what it believes the deliverables could be sold for on a stand-alone basis. The Company allocates consideration in all multiple element arrangements based on the relative fair value of the deliverables and recognizes revenue as services are delivered, assuming all other revenue recognition criteria have been met. Cost of Revenue Traffic Acquisition Costs Traffic acquisition costs consist of media costs for advertising impressions purchased from real-time bidding exchanges, which are expensed as incurred. The Company is billed by the advertising exchanges on a monthly basis for actual advertising impressions acquired. Other Cost of Revenue Other cost of revenue includes third-party data center and other advertisement-serving costs, depreciation of data center equipment, amortization of capitalized internal-use software cost for revenue-producing technologies, purchases of third-party data for specific marketing campaigns and salaries and related costs for the Company’s personnel dedicated to executing the Company’s advertising campaigns. Research and Development Research and development expenses include costs associated with the ongoing development of the Company’s technology, including compensation and employee benefits and allocated costs associated with the Company’s engineering and research and development departments, as well as costs for contracted services and supplies. Advertising and Marketing Advertising and marketing costs are expensed as incurred and totaled $3.7 million , $6.1 million and $3.9 million for the years ended December 31, 2014 , 2015 and 2016 , respectively. Stock-Based Compensation The Company accounts for stock options and restricted stock units (“RSU’s”) granted to employees and shares to be issued under its employee stock purchase plan (“ESPP”) based on their estimated fair values on the date of grant. The fair value of each stock option granted and share to be issued under its ESPP is estimated using the Black-Scholes option pricing model. The fair value of RSU’s is estimated based on the closing price of the underlying common stock on the date of grant. Stock-based compensation expense is recognized on a straight-line basis over the requisite service or offering period, net of estimated forfeitures. 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 consolidated financial statement carrying amounts of existing assets and liabilities and their respective tax basis, 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 statements of operations in the period when enacted. 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 assessment of whether or not a valuation allowance is required often requires significant judgment, including the long-range forecast of future taxable income and the evaluation of tax planning initiatives. Adjustments to the deferred tax valuation allowances are made to earnings in the period when such assessments are made. Due to the historical losses from the Company’s operations, a full valuation allowance on deferred tax assets has been recorded. Basic and Diluted Loss per Common Share Prior to the IPO, the Company used the two-class method to compute net loss per common share because the Company had issued securities, other than common stock, that contractually entitled the holders to participate in dividends and earnings of the Company. The two-class method requires earnings for the period to be allocated between common stock and participating securities based upon their respective rights to receive distributed and undistributed earnings. Each series of the Company’s convertible preferred stock were entitled to participate in distributions that were made to common stockholders, when and if declared by the board of directors, and therefore, were considered participating securities. Due to the net loss for the year ended December 31, 2014 , basic and diluted loss per share were the same, as the effect of potentially dilutive securities would have been anti-dilutive. Subsequent to the completion of the IPO, the Company no longer has outstanding participating securities. Therefore, the Company calculates net loss per basic share by dividing net loss by the weighted-average number of shares outstanding during the reporting period. The Company calculates net loss per diluted share by dividing net loss by the weighted-average number of shares outstanding during the reporting period plus the effects of any dilutive common stock-based instruments. Due to the net losses for the years ended 2015 and 2016 , basic and diluted loss per share were the same, as the effect of potentially dilutive securities would have been anti-dilutive. Recently Adopted Accounting Pronouncements In April 2015, the FASB issued ASU 2015-03, Simplifying the Presentation of Debt Issuance Costs . This accounting standards update is to simplify the presentation of debt issuance cost. This new guidance requires that debt issuance cost related to a recognized debt liability be presented in the balance sheet as a direct deduction from the carrying amount of that debt liability, consistent with the treatment of debt discounts. The accounting standards update does not affect the recognition and measurement guidance for debt issuance costs. In August 2015, the FASB issued ASU 2015-15, Presentation and Subsequent Measurement of Debt Issuance Costs Associated with Line-of-Credit Arrangements . This accounting standards update states that given the absence of authoritative guidance within ASU 2015-03 for debt issuance costs related to line of credit arrangements, the Securities and Exchange Commission would not object to an entity deferring and presenting debt issuance costs as an asset and subsequently amortizing the debt issuance costs ratably over the term of the line of credit arrangement, regardless of whether there are any outstanding borrowings on the line of credit arrangement. The Company adopted ASU 2015-03, effective January 1, 2016, on a retrospective basis. The adoption of these pronouncements did not have a material impact on the Company’s consolidated results of operations, financial position or cash flows. In August 2014, the FASB issued ASU 2014-15, Disclosure of Uncertainties about an Entity’s Ability to Continue as a Going Concern . This guidance addresses management’s responsibility to evaluate whether there is substantial doubt about an entity’s ability to continue as a going concern and to provide related footnote disclosures. Management’s evaluation should be based on relevant conditions and events that are known and reasonably knowable at the date that the financial statements are issued. ASU 2014-15 is effective for annual periods ending after December 15, 2016, and for interim periods within annual periods ending after December 15, 2016. Although early adoption was permitted, the Company did not early adopt this standard. The Company adopted ASU 2014-15 effective December 31, 2016. The adoption did not have a material effect on the Company’s consolidated financial statements, however, the Company has expanded its disclosures in the related notes thereto. In November 2015, the FASB issued ASU 2015-17, Balance Sheet Classification of Deferred Taxes. This accounting standards update simplifies the presentation of deferred income taxes by eliminating the current requirement for an entity to separate deferred income tax liabilities and assets into current and noncurrent amounts in a classified statement of financial position. ASU 2015-17 requires an entity to classify deferred income tax liabilities and assets, as well as any related valuation allowance, as noncurrent within a classified balance sheet. This accounting standards update is effective for interim or annual periods beginning after December 15, 2016, and can be applied retrospectively or prospectively. The Company elected to early adopt ASU 2015-17, effective December 31, 2016, on a retrospective basis. The Company’s now has, in each taxable jurisdiction, one deferred tax asset and liability, along with any related valuation allowance, classified as noncurrent on its consolidated balance sheets. The adoption did not have a material effect on the Company’s consolidated results of operations, financial position or cash flows as the Company has a full valuation allowance on deferred tax assets due to its historical losses from operations. Recent Accounting Pronouncements Not Yet Adopted In May 2014, the FASB issued ASU 2014-09, Revenue from Contracts with Customers . The new standard provides a single principles-based, five-step model to be applied to all contracts with customers, which steps are to (1) identify the contract(s) with the customer; (2) identify the performance obligations in the contract; (3) determine the transaction price; (4) allocate the transaction price to the performance obligations in the contract; and (5) recognize revenue when each performance obligation is satisfied. More specifically, revenue will be recognized when promised goods or services are transferred to the customer in an amount that reflects the consideration expected in exchange for those goods or services. This guidance states that an entity should recognize revenue to depict the transfer of promised goods or services to customers in an amount that reflects the consideration to which the entity expects to be entitled in exchange for those goods or services. In August 2015, the FASB issued ASU 2015-14, which defers the effective date of ASU 2014-09 for all entities by one year. In March 2016, the FASB issued ASU 2016-08, which clarifies the implementation guidance on principal versus agent considerations. In April 2016, the FASB issued ASU 2016-10, which clarifies the implementation guidance on identifying performance obligations and licensing. In May 2016, the FASB issued ASU 2016-11, Rescission of SEC Guidance Because of Accounting Standards Updates 2014-09 and 2014-16 Pursuant to Staff Announcements at the March 3, 2016 EITF Meeting , which rescinds SEC paragraphs pursuant to SEC staff announcements. These rescissions include changes to topics pertaining to accounting for shipping and handling fees and costs and accounting for consideration given by a vendor to a customer. In May 2016, the FASB issued ASU 2016-12, Narrow-Scope Improvements and Practical Expedients , which amends certain aspects of the new revenue recognition standard pursuant to ASU 2014-09. In December 2016, the FASB issued ASU 2016-20, which contains amendments that affect narrow aspects of the new revenue recognition guidance. ASU 2014-09, as amended by ASU 2015-14, is effective for interim or annual periods beginning after December 15, 2017. Early adoption of the standard is permitted, but not before the original effective date. The Company plans to adopt ASU 2014-09 as of January 1, 2018. The Company enters into contracts, or IOs, with customers either directly or through advertising agencies that act on behalf of its customers to deliver targeted digital marketing campaigns through various channels. Executed IOs typically have a term of less than three months and are cancelable at any time. The Company prices its marketing campaigns based on the number of advertising impressions and recognizes revenue as they are delivered. The Company is permitted to use either the retrospective or the modified retrospective method when adopting ASU 2014-09. The Company is currently evaluating the impact of this standard on its consolidated results of operations, financial position, cash flows and disclosures, and has not yet concluded on the method of adoption. In February 2016, the FASB issued ASU 2016-02, Leases (Topic 842) . The purpose of this guidance is to increase transparency and comparability among organizations by recognizing lease assets and lease liabilities on the balance sheet and disclosing key information about leasing arrangements. This guidance supersedes previous accounting guidance under Topic 840. Under ASU 2016-02, a lessee will be required to recognize assets and liabilities for the rights and obligations created by leases for leases with lease terms of more than 12 months. Lessor accounting remains substantially similar to current GAAP. In addition, disclosures of leasing activities are to be expanded to include qualitative along with specific quantitative information. ASU 2016-02 is effective for interim or annual periods beginning after December 15, 2018 and early adoption is permitted. This standard requires lessees and lessors to recognize and measure leases at the beginning of the earliest period presented using a modified retrospective approach. The Company does not expect to early adopt this guidance and is currently evaluating the impact of the adoption of this guidance on its consolidated results of operations, financial position and cash flows. In March 2016, the FASB issued ASU 2016-09, Improvements to Employee Share-Based Payment Accounting . ASU 2016-09 simplifies several aspects of the accounting for share-based payment transactions, including the income tax consequences, classification of awards as either equity or liabilities and classification on the statement of cash flows. ASU 2016-09 is effective for interim or annual periods beginning after December 15, 2016 and early adoption is permitted. The Company did not early adopt this standard and does not expect that adoption will have a material effect on its consolidated results of operations, financial position and cash flows. In August 2016, the FASB issued ASU 2016-15, Classification of Certain Cash Receipts and Cash Payments . This new standard provides guidance related to eight specific cash flow issues, with the objective of reducing diversity in practice of how certain cash receipts and payments are presented and classified in the statement of cash flows. ASU 2016-15 is effective for interim or annual periods beginning after December 15, 2017 and early adoption is permitted. ASU 2016-15 must be applied retrospectively, unless it is impracticable to do so, in which case the amendments would be applied prospectively as of the earliest date practicable. The Company does not expect to early adopt this guidance and is currently evaluating the impact of the adoption of this guidance on its consolidated results of operations, financial position and cash flows. In November 2016, the FASB issued ASU 2016-18, Restricted Cash . The purpose of this guidance is to reduce the diversity in practice that exists in the classification and presentation of changes in restricted cash on the statement of cash flows. This guidance requires that a statement of cash flows explain the change during the period in the total of cash, cash equivalents and amounts generally described as restricted cash or restricted cash equivalents. Therefore, amounts generally described as restricted cash and restricted cash equivalents should be included with cash and cash equivalents when reconciling the beginning-of-period and end-of-period total amounts shown on the statement of cash flows. ASU 2016-18 is effective for interim or annual periods beginning after December 15, 2017 and early adoption is permitted. This guidance must be applied retrospectively. The Company is currently evaluating the impact of the adoption of this guidance on its consolidated results of operations, financial position and cash flows.

Fair Value Measurements

Fair Value Measurements	12 Months Ended
	Dec. 31, 2016
Fair Value Disclosures [Abstract]
Fair Value Measurements	Fair Value Measurements 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 following table sets forth the Company’s financial instruments that were measured at fair value on a recurring basis as of December 31, 2015 by level within the fair value hierarchy (in thousands): December 31, 2015 Fair Value Level 1 Level 2 Level 3 Assets: Cash and cash equivalents — Money Market Fund $ 18,612 $ 18,612 $ — $ — Cash and Cash Equivalents The Company’s money market fund was valued using readily available market prices. As of December 31, 2016, the Company did not have a balance in this money market fund as all cash balances were maintained in demand deposit accounts. Short-term Debt The Company’s debt contains a variable rate of interest as of December 31, 2016 and therefore the carrying value of debt approximates its fair value. The fair value of debt falls within Level 3 of the fair value hierarchy as it is significantly driven by the creditworthiness of the Company, which is an unobservable input, and has not changed significantly since its most recent amendment to its line of credit in September 2016, described in Note 6. Common Stock Warrants In accordance with the Mezzanine Loan and Security Agreement entered into on June 12, 2014 and described in Note 6, the Company issued warrants to the lender to purchase 25,000 shares of common stock (the “Lender Warrants”) at an exercise price of $45.44 per share. The warrants were exercisable for an additional 12,500 shares of common stock at an exercise price of $45.44 per share, if the second tranche of $5.0 million was drawn prior to December 31, 2015 . The fair value of the warrants on the date of grant totaled $0.9 million and was recorded as a discount on long-term debt and as a long-term liability in the consolidated balance sheets. The debt discount was being amortized over the term of the Mezzanine Loan and Security Agreement as reflected in the consolidated statements of operations. On December 16, 2014 the Company borrowed the second tranche of the Mezzanine Loan and Security Agreement in the amount of $5.0 million and the portion of the warrants related to the additional 12,500 shares of common stock became exercisable on that date. As of December 31, 2014, these warrants were classified as liabilities because the Company did not meet the criteria under the relevant accounting standard for treatment as equity instruments. As a result, these warrants were remeasured to their fair value at the end of each reporting period. As described in Note 8, on February 10, 2015 the Company increased its number of authorized common shares. On that date, these outstanding warrants satisfied the criteria to be treated as equity instruments and the related liabilities were reclassified to additional paid-in capital. The change in fair value between January 1, 2015 and February 10, 2015 was recorded as a derivative fair value adjustment related to common stock warrants in the consolidated statements of operations. For the years ended December 31, 2014 , 2015 and 2016 , the Company recorded an unfavorable $0.7 million , a favorable $0.5 million and zero change in fair value adjustments related to these Lender Warrants, respectively. On February 12, 2015 , the Company amended its Mezzanine Loan and Security Agreement, (the “Amended Mezzanine Loan and Security Agreement”), as described in Note 6. As part of the Amended Mezzanine Loan and Security Agreement, the Company issued an additional warrant to the lender (“Additional Lender Warrant”) to purchase 12,500 shares of common stock at a price of $60.72 per share. The fair value of the Additional Lender Warrant on the date of grant totaled $0.3 million and was recorded as a discount on long-term debt and as additional paid-in capital in the consolidated balance sheets as the warrant met the criteria under the relevant accounting standard for treatment as an equity instrument. As this warrant was classified as an equity instrument, it is not subject to fair value adjustments on a recurring basis. The debt discount was being amortized over the term of the Amended Mezzanine Loan and Security Agreement as reflected in the consolidated statements of operations. As described in Note 6, in early 2015 the Company repaid the total Amended Mezzanine Loan and Security Agreement balance. Based on the early repayment of the balance related to this agreement, the Company reflected within the consolidated statements of operations the write-off of the corresponding debt discount and deferred financing costs. The following table presents the changes in the Company’s Lender Warrants measured at fair value on a recurring basis during the years ended December 31 (in thousands): 2014 2015 Balance as of January 1 $ — $ 1,614 Issuance of warrants 943 — Change in fair value of warrants liability 671 (482 ) Reclassification of warrants to equity — (1,132 ) Balance as of December 31 $ 1,614 $ — In order to determine the fair value of the Lender Warrants, the Company used an option pricing model. These valuations require the input of subjective assumptions, including the estimated enterprise fair value, risk-free interest rate and expected stock price volatility. The risk-free interest rate assumption is based upon observed interest rates for constant maturity U.S. Treasury securities consistent with the term of the instruments. The expected stock price volatility assumption is based on historical volatilities for publicly traded stock of comparable companies over the term of the instruments. The following table summarizes the assumptions used for estimating the fair value of the Lender Warrants for the years ended December 31: 2014 2015 Risk-free interest rate 2.13% - 2.58% 1.97% Expected term (years) 9.45 - 10.00 9.34 Expected volatility 57% - 58% 58% Dividend yield —% —% Stock Option Liability Awards During the year ended December 31, 2014, the number of stock options granted by the Company exceeded the number of shares authorized for issuance and not already committed for other purposes, such as convertible preferred stock, warrants and previously granted stock option awards. As a result, those options granted during the year ended December 31, 2014 that exceeded the authorized limit were accounted for as liability-based awards and recorded in other long-term liabilities in the consolidated balance sheets as of December 31, 2014. During the year ended December 31, 2014, the Company granted 152,668 options, cumulatively, in excess of its common shares authorized. Of these, 149,356 were outstanding as of December 31, 2014. The Company recorded a liability of $0.5 million in its consolidated balance sheets as of December 31, 2014, and recorded stock-based compensation expense of $0.5 million related to these liability-based equity awards. The fair value of the liability-based awards was estimated each reporting period, and changes in the estimate of fair value were reflected in the amount of stock-based compensation expense recorded during the period. Changes in fair value are recorded in stock-based compensation expense for the period. As described in Note 8, on February 10, 2015 , the Company increased its number of authorized common shares by 3,000,000 shares. As the number of shares authorized was in excess of those committed for other purposes as of that date, the liability-based awards described above were reclassified to equity-based awards at fair value and reclassified to additional paid-in capital. The favorable fair value adjustment for liability-based awards for the year ended December 31, 2015 was $0.2 million . The reclassification from other long-term liabilities to additional paid-in capital in the consolidated balance sheets was $0.3 million as of February 10, 2015 . The following table presents the changes in the recorded liability associated with certain of the Company’s stock option awards which, as described above, have been accounted for as liability-based awards during the years ended December 31 (in thousands): 2014 2015 Balance as of January 1 $ — $ 461 Issuance of stock options 410 — Change in fair value of stock options classified as liability awards 51 (173 ) Reclassification of stock options classified as liability awards to equity — (288 ) Balance as of December 31 $ 461 $ — In order to determine the fair value of the stock options classified as liability awards, the Company used an option pricing model. These valuations require the input of subjective assumptions, including the estimated enterprise fair value, risk-free interest rate and expected stock price volatility. The risk-free interest rate assumption is based upon observed interest rates for constant maturity U.S. Treasury securities consistent with the term of the instruments. The expected stock price volatility assumption is based on historical volatilities for publicly traded stock of comparable companies over the term of the instruments. The following table summarizes the assumptions used for estimating the fair value of the stock options classified as liability awards for the years ended December 31: 2014 2015 Risk-free interest rate 1.61% - 2.00% 1.46% - 1.67% Expected term (years) 4.85 - 6.08 4.74 - 6.03 Expected volatility 56% - 58% 51% - 53% Dividend yield —% —%

Property, Equipment and Softwar

Property, Equipment and Software, Net	12 Months Ended
	Dec. 31, 2016
Property, Plant and Equipment [Abstract]
Property, Equipment and Software, Net	Property, Equipment and Software, Net Property, equipment and software, net consisted of the following as of December 31 (in thousands): 2015 2016 Capitalized internal-use software costs $ 14,800 $ 21,993 Computer hardware and software 16,028 18,091 Furniture and office equipment 340 440 Leasehold improvements 863 1,967 Total 32,031 42,491 Less: accumulated depreciation (12,646 ) (22,366 ) Property, equipment and software, net $ 19,385 $ 20,125 Depreciation and amortization expense for the years ended December 31, 2014 , 2015 and 2016 was $3.1 million , $6.1 million and $9.8 million , respectively.

Accrued Expenses and Other Curr

Accrued Expenses and Other Current Liabilities	12 Months Ended
	Dec. 31, 2016
Payables and Accruals [Abstract]
Accrued Expenses and Other Current Liabilities	Accrued Expenses and Other Current Liabilities Accrued expenses consisted of the following as of December 31 (in thousands): 2015 2016 Accrued commissions $ 2,713 $ 2,517 Accrued bonuses 1,190 2,037 Accrued salaries, wages, benefits and related costs 1,190 371 Accrued credit card purchases 645 597 Other accrued expenses and current liabilities 2,648 3,878 Accrued expenses and other current liabilities $ 8,386 $ 9,400

Debt

Debt	12 Months Ended
	Dec. 31, 2016
Debt Disclosure [Abstract]
Debt	Debt On June 12, 2014 , the Company terminated its loan and security agreement with its previous lender and entered into two debt arrangements with a new lender. The first debt arrangement was a term loan and security agreement (the Mezzanine Loan and Security Agreement). The second debt arrangement was the New Loan and Security Agreement. The New Loan and Security Agreement included a revolving line of credit, (the “New Revolving Line of Credit”). The proceeds from these new debt arrangements were used to pay off existing debt from a previous lender, in addition to providing additional working capital for general corporate purposes. Mezzanine Loan and Security Agreement The Mezzanine Loan and Security Agreement included a term loan with a total commitment of $15.0 million comprised of two separate tranches. The first tranche draw of $10.0 million occurred at closing and the second tranche of $5.0 million was drawn on December 16, 2014 . The Mezzanine Loan and Security Agreement was secured by substantially all of the Company’s assets. The Mezzanine Loan and Security Agreement had a maturity date of June 12, 2017 . The interest rate on outstanding amounts under the Mezzanine Loan and Security Agreement was fixed at 11.50% . Interest was payable monthly and the cumulative principal was due at maturity. The Company had the option to prepay all, but not less than all, of the principal balances of the Mezzanine Loan and Security Agreement at any time without a prepayment fee or penalty. As described in Note 3, under the terms of the Mezzanine Loan and Security Agreement, the Company issued common stock warrants (Lender Warrants) to the lender. On February 12, 2015 , the Company amended its Mezzanine Loan and Security Agreement (the Amended Mezzanine Loan and Security Agreement). The Amended Mezzanine Loan and Security Agreement increased available borrowings by $5.0 million (the “2015 Term Loan”). An additional draw under the Amended Mezzanine Loan and Security Agreement occurred on February 12, 2015. There was no modification to the original maturity date or any other significant terms with the Amended Mezzanine Loan and Security Agreement. As described in Note 3, as part of the Amended Mezzanine Loan and Security Agreement, the Company issued an additional common stock warrant to the lender (Additional Lender Warrant). On March 20, 2015 and March 30, 2015, the Company repaid the first and second tranches of the Amended Mezzanine Loan and Security Agreement totaling $15.0 million . On April 1, 2015, the Company repaid the 2015 Term Loan of $5.0 million , which represented the remaining principal balance on the Amended Mezzanine Loan and Security Agreement. As a result of the repayment of these tranches, the Company reflected within the consolidated statements of operations the write-off of the corresponding debt discount and deferred financing costs. New Loan and Security Agreement The New Loan and Security Agreement included a revolving line of credit of potential maximum aggregate advances (the “New Revolving Line of Credit”) totaling $30.0 million . Borrowing availability under the revolving the New Revolving Line of Credit was measured by reference to a formula based on the amount of certain eligible accounts receivable (but not exceeding the aggregate principal amount of commitments under the revolving line of credit). The New Revolving Line of Credit had a maturity date of June 12, 2016 . The interest rate on outstanding amounts under the New Revolving Line of Credit was a floating rate per annum equal to the prime referenced rate plus a potential applicable margin of 1.00% . Interest was payable monthly. In addition, the Company was required to maintain, at all times, $5.0 million , consisting of the sum of: (i) cash held at the lender (determined in accordance with the New Loan and Security Agreement); plus (ii) the unused availability amount on its line of credit; plus (iii) the undrawn portion of the term loan advance related to the Mezzanine Loan and Security Agreement, described above. On February 12, 2015 , the Company amended its New Loan and Security Agreement (the “Amended New Loan and Security Agreement”). The amended New Revolving Line of Credit (the “Amended New Revolving Line of Credit”) was increased by $5.0 million . There was no modification to the original maturity date or any other significant terms with the Amended New Loan and Security Agreement. On March 8, 2016 , the Company entered into a second amendment to its Amended New Loan and Security Agreement. The “Second Amended New Loan and Security Agreement” changed the following terms and conditions to the Amended New Loan and Security Agreement and Amended New Revolving Line of Credit (the “Second Amended New Revolving Line of Credit”) by: (1) extending the maturity date to June 11, 2017 ; (2) removing the $5.0 million minimum cash and availability requirement (defined as cash held at the lender plus the unused credit line availability amount); and (3) changing the applicable interest rate on outstanding amounts under the Second Amended New Revolving Line of Credit to a floating rate per annum equal to the prime referenced rate plus a potential applicable margin ranging from 0.00% to 1.50% . In addition, with this amendment, the Company was required to comply with certain financial covenants, including Adjusted EBITDA thresholds and Adjusted Quick Ratio metrics. On September 30, 2016, the Company entered into a third amendment to its Amended New Loan and Security Agreement (the “Third Amended New Loan and Security Agreement”). The Third Amended New Loan and Security Agreement changed the following terms and conditions to the Second Amended New Loan and Security Agreement and Second Amended New Revolving Line of Credit (the “Third Amended New Revolving Line of Credit”) by: (1) extending the maturity date to December 31, 2017 ; (2) including in the revolving line of credit borrowing base calculation certain eligible unbilled accounts receivable; (3) adjusting the borrowing base calculation to be (a) 85% of eligible accounts receivable, plus (b) the lesser of (i) 75% of eligible unbilled accounts or (ii) $12,250,000 ; (4) modifying the definition of eligible accounts receivable for the revolving line of credit borrowing base by including up to 25% of certain eligible foreign accounts receivable, including those payable from Canada, Australia, France, Germany, Israel, Italy, Japan and the United Kingdom; (5) providing that all future cash collections from accounts receivable directly reduce the outstanding balance of the revolving credit facility; (6) fixing the applicable interest rate on future outstanding amounts under the revolving line of credit to a rate per annum equal to the prime referenced rate plus 0.5% ; (7) reducing certain financial covenants regarding the required monthly minimum adjusted quick ratio, as defined and described below, in addition to removing certain previous ratio thresholds which could have resulted in a range of applicable interest rates; and (8) changing the amounts related to the Company’s financial covenants regarding specified quarterly adjusted EBITDA requirements, as defined and described below. The Third Amended New Revolving Line of Credit allows for potential maximum aggregate advances of $35.0 million . The amount available is: (a) the lesser of (i) the Third Amended New Revolving Line of Credit or (ii) the amount available under the borrowing base, as determined by lender; minus (b) the outstanding principal balance of any advances. All cash collections from accounts receivable directly reduce the outstanding balance of the revolving credit facility. There were no modifications to any other significant terms with the Third Amended New Loan and Security Agreement. As of December 31, 2016 , the Company had approximately $5.0 million of availability under the line of credit. The effective interest rate for the Third Amended New Revolving Line of Credit was 4.25% as of December 31, 2016 . The loan is secured by substantially all of the Company’s assets. Under the terms of the Third Amended New Loan and Security Agreement, the Company is required to meet and maintain certain customary financial and nonfinancial covenants, one of which restricts the Company’s ability to pay any dividends or make any distribution or payment to redeem, retire or purchase any capital stock, subject to certain specified exceptions. The Company must also maintain with the lender all of its primary domestic operating and other deposit and investment accounts consisting of at least 95% of the Company’s total cash and cash equivalents. This agreement also includes customary subjective acceleration clauses; in addition, the Company is required to comply with certain financial covenants, including the following: Adjusted EBITDA . The Company is required to maintain specified quarterly Adjusted EBITDA, which is defined for this purpose, with respect to any trailing twelve month period, as an amount equal to the sum of net income, plus (a) interest expense, plus (b) to the extent deducted in the calculation of net income, depreciation expense and amortization expense, plus (c) income tax expense, plus or minus (d) change in deferred revenue, less, (e) capitalized software development expenses, plus (f) any non-cash items such as stock-compensation expense (and other mutually agreed upon non-cash items), plus one-time non-recurring charges subject to the lenders approval. This covenant is tested on a quarterly basis. Adjusted Quick Ratio . The Company is required to maintain at all times a 1.0 monthly minimum Adjusted Quick Ratio, which is defined as the ratio of cash held at the lender and cash equivalents plus net accounts receivables to current liabilities (including all debt outstanding under the Third Amended New Revolving Line of Credit) minus the current portion of deferred revenue. This covenant is tested on a monthly basis. As of December 31, 2016 , the Company was in compliance with all financial and nonfinancial covenants. As of December 31, 2015 and 2016 , the outstanding borrowings under the Company’s revolving line of credit were $31.2 million and $27.5 million , respectively, and are presented as a short-term obligation in both periods.

Employee Retirement Savings Pla

Employee Retirement Savings Plan	12 Months Ended
	Dec. 31, 2016
Compensation and Retirement Disclosure [Abstract]
Employee Retirement Savings Plan	Employee Retirement Savings Plan Effective July 1, 2011, the Company established the MaxPoint Interactive, Inc. 401(k) Profit Sharing Plan (the “Retirement Plan”) covering all permanent full-time employees who are at least 21 years of age. Retirement Plan participants may make a combination of pre-tax and after-tax elective contributions, up to the maximum percentage of compensation and dollar amount limits under the Internal Revenue Code. Retirement Plan participants are immediately vested in their elective contributions. Company contributions to the Retirement Plan are discretionary. There were no Company contributions to the Retirement Plan for the years ended December 31, 2014 , 2015 and 2016 .

Common and Preferred Stock

Common and Preferred Stock	12 Months Ended
	Dec. 31, 2016
Stockholders' Equity, Number of Shares, Par Value and Other Disclosures [Abstract]
Common and Preferred Stock	Common and Preferred Stock Authorized Common Shares On February 10, 2015 , the Company amended its amended and restated certificate of incorporation to increase its number of authorized common shares by 3,000,000 for a total of 25,000,000 . Initial Public Offering As described in Note 1, on the Closing Date, the Company completed an IPO of its common stock. As part of the consummation of this transaction, the Company amended and restated its amended and restated certificate of incorporation. Effective as of the Closing Date, the Company is authorized to issue 510,000,000 total shares, consisting of 500,000,000 shares of common stock and 10,000,000 shares of preferred stock. Both the common stock and preferred stock have a par value of $0.00005 per share. Liquidation Rights In the event of any liquidation or dissolution of the Company, the holders of common stock are entitled to the remaining assets and funds of the Company legally available for distribution, subject to the rights of the holders of preferred stock. Dividend and Voting Rights The holders of common stock are entitled to receive dividends, as and if declared by the Company, subject to the rights of the holders of preferred stock. Holders of common stock have the right to one vote per share. Common Stock Reserved for Issuance The Company’s shares of common stock reserved for issuance as of December 31, 2015 and 2016 were as follows: 2015 2016 Lender warrants to purchase common stock 50,000 50,000 Stock options outstanding 1,074,473 1,026,244 Unvested restricted stock units — 536,100 Possible future issuance under equity incentive plan 380,460 189,513 Possible future issuance under employee stock purchase plan 60,318 66,823 Total shares reserved 1,565,251 1,868,680 Preferred Stock Effective as of the Closing Date, shares of preferred stock may be issued from time to time in one or more series. The board of directors is authorized to provide for the issuance, out of the unissued shares of preferred stock, of one or more series of preferred stock, by establishing the number of shares to be included in such series, voting powers, preferences, participation, or other special rights, if any, of the shares of each such series and any qualifications, limitations or restrictions thereof. The Company did not have any outstanding preferred stock as of December 31, 2016 .

Convertible Preferred Stock

Convertible Preferred Stock	12 Months Ended
	Dec. 31, 2016
Temporary Equity, Other Disclosures [Abstract]
Convertible Preferred Stock	Convertible Preferred Stock As described in Note 8, on the Closing Date, the Company completed an IPO of its common stock. Upon the completion of the IPO, all outstanding shares of the Company’s convertible preferred stock were automatically converted into an aggregate of 3,712,206 shares of common stock. The following table summarizes the issuances of convertible preferred stock subject to conversion as of the IPO completion: Number of Shares Authorized Number of Shares Outstanding Original Issue and Conversion Price per Share Series A convertible preferred stock 621,626 595,936 $ 2.328 Series B convertible preferred stock 912,342 912,342 $ 3.38624 Series C convertible preferred stock 1,351,626 1,351,626 $ 5.9192 Series D convertible preferred stock 852,312 852,302 $ 15.2528 Total convertible preferred stock 3,737,906 3,712,206 The Series A, Series B, Series C and Series D convertible preferred stock are collectively referred to as the “Preferred Stock,” and individually as the “Series A,” “Series B,” “Series C,” and “Series D.” The “Original Issue Price” per share excludes the cost of issuance. Prior to the consummation of the IPO, the Company had determined that its convertible preferred stock was contingently redeemable due to the existence of deemed liquidation provisions contained in its former certificate of incorporation, and therefore classified its convertible preferred stock outside of permanent equity. Summary of Activity The following table presents a summary of activity for the convertible preferred stock issued and outstanding for the years ended December 31, 2014 and 2015 (in thousands): Convertible Preferred Stock Series A Series B Series C Series D Total Amount Balance as of December 31, 2014 $ 1,387 $ 3,089 $ 8,000 $ 13,000 $ 25,476 Conversion to common stock upon IPO (1,387 ) (3,089 ) (8,000 ) (13,000 ) (25,476 ) Balance as of December 31, 2015 $ — $ — $ — $ — $ — Conversion Rights The holders of the Company’s Preferred Stock were entitled to convert their shares into common stock at any time. The number of shares of common stock issued upon conversion was determined based on the number of converted Preferred Stock shares and the conversion price. The conversion price varied based upon the occurrence of certain events, such as stock splits, business combinations, issuances of common stock dividends and distributions, recapitalizations, mergers, consolidations and sales of common stock below the Preferred Stock conversion price.

Stock-Based Compensation

Stock-Based Compensation	12 Months Ended
	Dec. 31, 2016
Disclosure of Compensation Related Costs, Share-based Payments [Abstract]
Stock-Based Compensation	Stock-Based Compensation Equity Incentive Plans Prior to the IPO, the Company had a stock-based compensation plan, the 2010 Equity Incentive Plan (the “2010 Plan”) under which the Company granted options to purchase shares of common stock to employees, directors and consultants. In January 2015, the Company’s board of directors adopted the 2015 Equity Incentive Plan (the “2015 Plan”), which was subsequently ratified by its stockholders in February 2015. The 2015 Plan became effective immediately on adoption although no awards were to be made under it until the Effective Date. The 2015 Plan is the successor to and continuation of the 2010 Plan. As of the Effective Date, no additional awards are to be granted under the 2010 Plan, but all stock awards granted under the 2010 Plan remain subject to their existing terms. The number of shares of the Company’s common stock reserved for issuance under the 2015 Plan equaled the sum of 625,000 shares plus up to 1,134,467 shares reserved for issuance under the 2010 Plan. Of this amount, 189,513 shares are available for future grants to employees, non-employee directors, consultants and advisors as of December 31, 2016 . The 2015 Plan provides for the grant of the following awards: (i) incentive and nonstatutory stock options; (ii) stock appreciation rights; (iii) restricted shares; (iv) stock units; and (v) performance cash awards. The number of shares reserved for issuance under the 2015 Plan will be increased automatically on the first business day of each of the Company’s fiscal years, commencing in 2016, by a number equal to the least of: (1) 437,500 shares; (2) 5% of the shares of common stock outstanding on the last business day of the prior fiscal year; or (3) the number of shares determined by the Company’s board of directors. The compensation committee of the Company’s board of directors administers the 2015 Plan. The compensation committee has complete discretion to make all decisions relating to the 2015 Plan and outstanding awards. The Company’s board of directors may amend or terminate the 2015 Plan at any time. If the Company’s board of directors amends the 2015 Plan, it does not need stockholder approval of the amendment unless required by applicable law, regulation or rules. The 2015 Plan will terminate automatically ten years after the later of the date when the Company’s board of directors adopted the 2015 Plan, or approved the latest share increase that was also approved by the Company’s stockholders. Stock Options The terms of the stock options, including the exercise price per share and vesting provisions, are determined by the board of directors. Historically, stock options were granted at exercise prices not less than the estimated fair market value of the Company’s common stock at the date of grant based upon numerous objective and subjective factors including: third-party valuations, preferred stock transactions with third-parties, current operating and financial performance, management estimates and future expectations. Subsequent to the completion of the IPO, the fair value of the Company’s common stock on the grant date has been equal to the most recent closing price of the Company’s stock on the New York Stock Exchange, or beginning May 13, 2016, on the Nasdaq. Stock option grants typically vest upon the expiration of an initial one year cliff and vest monthly thereafter over the remaining thirty-six months assuming continuing service, and expire ten years from the grant date. Stock-based compensation expense related to stock options is included in the following line items in the consolidated statements of operations for the years ended December 31 (in thousands): Year Ended December 31, 2014 (1) 2015 (2) 2016 Other cost of revenue $ 20 $ 75 $ 75 Sales and marketing 505 720 719 Research and development 756 1,114 1,268 General and administrative 1,058 1,444 1,539 $ 2,339 $ 3,353 $ 3,601 (1) Stock-based compensation expense included an unfavorable $0.5 million fair value adjustment related to stock option liability awards during the year ended December 31, 2014 . See Note 3 for further description of the accounting treatment for these awards. (2) Stock-based compensation expense included a favorable $0.2 million fair value adjustment related to stock option liability awards prior to reclassification to additional paid-in capital during the year ended December 31, 2015 . See Note 3 for further description of the accounting treatment for these 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. The Company uses the simplified method due to the lack of sufficient historical exercise data to provide a reasonable basis upon which to otherwise estimate the expected life of the stock options. Expected volatility is based on historical volatilities for publicly traded stock of comparable companies over the estimated expected life of the stock options. The Company assumes no dividend yield, 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 to employees for the years ended December 31 : 2014 2015 2016 Risk-free interest rate 1.32% - 2.04% 1.57% - 1.94% 1.16% - 2.10% Expected term (years) 4.00 - 6.08 6.03 - 6.08 6.08 Expected volatility 56% - 60% 46% - 59% 46% - 47% Dividend yield —% —% —% The weighted-average grant date fair value for the Company’s stock options granted during the years ended December 31, 2014 , 2015 and 2016 was $28.24 , $11.20 and $3.87 per share, respectively. The total compensation cost related to unvested stock options not yet recognized as of December 31, 2016 was $5.7 million and will be recognized over a weighted-average period of approximately 1.03 years . The aggregate intrinsic value of stock options exercised during the years ended December 31, 2014 , 2015 and 2016 was $5.4 million , $3.9 million and $0.2 million , respectively. There was no associated income tax benefit recognized for the years ended December 31, 2014 , 2015 and 2016 based on the Company’s valuation allowance that is recorded against its net deferred tax assets. The following table summarizes the Company’s stock option activity for the year ended December 31, 2016 : Number of Options Weighted- Average Exercise Price Weighted- Average Remaining Contractual Term Aggregate Intrinsic Value (in years) (in thousands) Outstanding balance at January 1, 2016 1,074,473 $ 30.69 8.39 $ 500 Granted 133,760 8.44 Exercised (31,125 ) 3.65 Cancelled (150,864 ) 29.84 Outstanding balance at December 31, 2016 1,026,244 $ 28.73 7.65 $ 299 Exercisable at December 31, 2016 565,043 $ 30.65 6.91 $ 299 Vested and expected to vest at December 31, 2016 986,301 $ 29.17 7.60 $ 299 The following table provides a summary of options outstanding and vested as of December 31, 2016 : Options Outstanding Options Exercisable Exercise Prices Number of Options Weighted Average Exercise Price Weighted- Average Remaining Contractual Term (in Years) Number of Options Weighted Average Exercise Price Weighted- $1.36 - $15.00 313,087 $ 7.11 6.97 175,117 $ 6.10 5.10 $15.01 - $30.00 287,808 20.26 8.52 111,696 20.35 8.31 $30.01 - $45.00 59,336 36.48 8.02 30,116 36.61 7.75 $45.01 - $60.72 366,013 52.63 7.49 248,114 51.89 7.46 1,026,244 $ 28.73 7.65 565,043 $ 30.65 6.91 Restricted Stock Units The terms of the RSU’s, including the vesting provisions, are determined by the board of directors. Each restricted stock unit represents the contingent right to receive one share of common stock of the Company. The RSU’s granted typically vest over a two-year term upon the expiration of an initial six months cliff period and vest quarterly thereafter assuming continuing service. The Company initially granted RSU’s during the year ended December 31, 2016 . Stock-based compensation expense related to RSU’s is included in the following line items in the consolidated statements of operations for the year ended December 31(in thousands): 2016 Other cost of revenue $ 27 Sales and marketing 104 Research and development 294 General and administrative 163 $ 588 The following table summarizes the Company’s restricted stock unit activity for the year ended December 31, 2016 : Number of Weighted- Nonvested balance at January 1, 2016 — $ — Granted 566,420 8.87 Vested — — Forfeited (30,320 ) 8.87 Nonvested balance at December 31, 2016 536,100 $ 8.87 The total compensation cost related to nonvested RSU’s not yet recognized as of December 31, 2016 was $4.2 million and will be recognized over a weighted-average period of approximately 0.97 years . Employee Stock Purchase Plan In January 2015, the Company’s board of directors adopted the 2015 Employee Stock Purchase Plan (the “2015 ESPP”), which was subsequently ratified by its stockholders in February 2015. The 2015 ESPP began as of the Effective Date. The 2015 ESPP allows eligible employees to purchase shares of common stock at a discount through payroll deductions of up to 15% of their eligible compensation, subject to a total maximum share number of 375 per offering period and maximum share value of $25,000 per calendar year. The price at which common stock is purchased under the 2015 ESPP is equal to 85% of the fair market value of the common stock on the first day of an offering period or on the purchase date, whichever is lower. Unless otherwise determined by the compensation committee, two offering periods of six months’ duration will begin in each year on May 1 and November 1. Due to the timing of the Company’s IPO, the first offering period started on March 5, 2015 and ended on October 30, 2015. For the year ended December 31, 2016 , the Company issued 55,995 shares under the 2015 ESPP. The Company has accumulated employee withholdings of $0.2 million as of December 31, 2016 associated with the next purchase date. Stock-based compensation expense related to the 2015 ESPP is included in the following line items in the consolidated statements of operations for the years ended December 31 (in thousands): 2015 2016 Other cost of revenue $ 17 $ 4 Sales and marketing 177 64 Research and development 244 125 General and administrative 66 27 $ 504 $ 220 All Company employees are eligible to participate if they are employed for more than 20 hours per week and for more than five months per year. Eligible employees may begin participating in the 2015 ESPP at the start of any offering period. Each offering period will last a number of months determined by the compensation committee of the board of directors, not to exceed 27 months . A new offering period will begin periodically, as determined by the compensation committee. Offering periods may overlap or may be consecutive. The Company initially reserved 93,750 shares of its common stock for issuance under the 2015 ESPP. The number of shares reserved for issuance under the 2015 ESPP will automatically be increased on the first business day of each of the Company’s fiscal years, commencing in 2016, by a number equal to the least of: (1) 62,500 shares; (2) 1% of the shares of common stock outstanding on the last business day of the prior fiscal year; or (3) the number of shares determined by the Company’s board of directors. The compensation committee of the Company’s board of directors will administer the 2015 ESPP. The board of directors or the compensation committee may amend or terminate the 2015 ESPP at any time. The fair value of the “look back” option for 2015 ESPP shares issued from the offering period is estimated using: (1) a 15% discount on the purchase of the stock; (2) 85% of the fair value of the call option; and (3) 15% of the fair value of the put option. The following table summarizes the assumptions used in the Black-Scholes option pricing model for estimating the fair value of shares to be granted under the 2015 ESPP for the offering periods during the year ended December 31 : 2015 2016 Risk-free interest rate 0.10% - 0.27% 0.41% - 0.50% Expected term (years) 0.50 - 0.59 0.50 Expected volatility 55% - 61% 41% - 43% Dividend yield —% —% The grant date fair value per ESPP share for the first and second offering periods, for the years ended December 31, 2015 and 2016, was $15.38 , $5.98 , $2.23 and $2.35 , respectively. The intrinsic value of shares of the Company’s stock purchased pursuant to the 2015 ESPP for offering periods within each of the years ended December 31, 2015 and 2016 was $0.1 million . As of December 31, 2016 , the total unrecognized stock-based compensation cost related to the 2015 ESPP was $0.1 million and will be recognized over a period of approximately 0.3 years .

Income Taxes

Income Taxes	12 Months Ended
	Dec. 31, 2016
Income Tax Disclosure [Abstract]
Income Taxes	Income Taxes As of December 31, 2016, the Company elected to early adopt new accounting guidance that requires that all deferred tax assets and liabilities, along with any related valuation allowance, be classified as noncurrent on a classified balance sheet. This adoption, and retrospective application, had no impact to the consolidated financial statements due to the historical losses from the Company’s operations and the related valuation allowances on deferred tax assets. Prior period disclosures, in the tables that follow, have been adjusted to reflect the adoption of this simplification guidance. The following table presents domestic and foreign components of loss before income taxes for the periods presented (in thousands of dollars): Year Ended December 31, 2014 2015 2016 Domestic $ (11,222 ) $ (19,917 ) $ (15,086 ) International (1,767 ) (2,536 ) (2,765 ) Total $ (12,989 ) $ (22,453 ) $ (17,851 ) Taxes computed at the statutory U.S. federal income tax rate of 34% are reconciled to the provision for income taxes as follows (in thousands of dollars): Year Ended December 31, 2014 2015 2016 Effective tax rate 0 % 0 % 0 % Statutory rate of 34% $ (4,416 ) $ (7,634 ) $ (6,069 ) State taxes, net of federal benefit (256 ) (615 ) (388 ) Foreign rate differential 245 346 455 Stock-based compensation permanent differences 464 836 785 Meals and entertainment permanent differences 232 385 376 Miscellaneous permanent differences 32 165 264 Warrant fair market value adjustment 229 (59 ) — Other adjustments 474 (3 ) (96 ) Change in valuation allowance 2,996 6,579 4,673 Provision for income taxes $ — $ — $ — Components of the deferred tax assets were as follows (in thousands of dollars): December 31, 2015 2016 Accrued expenses $ 882 $ 1,303 Stock-based compensation 854 1,611 Future benefit of carry forward losses 17,946 21,742 Other accruals 488 678 Valuation allowance (14,871 ) (19,544 ) Total deferred tax asset $ 5,299 $ 5,790 Components of deferred tax liabilities were as follows (in thousands of dollars): December 31, 2015 2016 Amortization $ (3,688 ) $ (4,482 ) Depreciation (1,591 ) (1,308 ) Other accruals (20 ) — Total deferred tax liability $ (5,299 ) $ (5,790 ) Net deferred tax assets (liabilities) $ — $ — The Company has U.S. federal operating loss carry forwards at December 31, 2016 of $57.2 million that will begin to expire in 2026 . The Company also has state operating loss carry forwards of $48.8 million that will begin to expire in 2021 and foreign operating loss carry forwards of $7.1 million that do not expire . The Company applies the accounting guidance for uncertainties in income taxes, which prescribes a recognition threshold and measurement process for recording uncertain tax positions taken, or expected to be taken, in a tax return in the financial statements. Additionally, the guidance also prescribes the treatment for the derecognition, classification, accounting in interim periods and disclosure requirements for uncertain tax positions. The Company accrues for the estimated amount of taxes for uncertain tax positions if it is more likely than not that the Company would be required to pay such additional taxes. An uncertain tax position will be recognized if it is more likely than not to be sustained. The Company has determined that any uncertain tax positions for the tax years open for examination would have no material impact on the consolidated financial statements. In accordance with Section 382 of the Internal Revenue Code of 1986, as amended, a change in equity ownership of greater than 50% within a three-year period results in an annual limitation on the Company’s ability to utilize its NOL carryforwards created during the tax periods prior to change in ownership. The Company has determined that ownership changes have occurred and as a result, a portion of the Company’s NOL carryforwards might be limited. With respect to foreign earnings, it is the Company’s policy to invest the earnings of foreign subsidiaries indefinitely outside the United States. As of December 31, 2016 , the Company’s non-U.S. subsidiary had no undistributed earnings.

Commitments and Contingencies

Commitments and Contingencies	12 Months Ended
	Dec. 31, 2016
Commitments and Contingencies Disclosure [Abstract]
Commitments and Contingencies	Commitments and Contingencies Litigation The Company is subject to various legal matters and claims in the ordinary course of business. Although the results of legal proceedings and claims cannot be predicted with certainty, including the matters noted below, in the opinion of management, there are currently no such known matters that will have a material effect on the financial condition, results of operations or cash flows of the Company. The Company, certain of its officers and directors, and certain investment banking firms who acted as underwriters in connection with the Company’s IPO, have been named as defendants in a putative class action lawsuit filed August 31, 2015 in the United States District Court for the Southern District of New York. The complaint alleges that the defendants violated Sections 11, 12 and 15 of the Securities Act by not including information regarding customer concentration, which the complaint characterizes as a known trend and/or significant factor required to be disclosed under federal securities regulations. The complaint seeks unspecified damages, interest and other costs. The Court appointed a Lead Plaintiff on November 18, 2015, and on January 19, 2016 the Lead Plaintiff filed a First Amended Complaint that repeats the same substantive allegations included in the initial complaint and continues to seek unspecified damages. On March 24, 2016, the Company filed a motion to dismiss the First Amended Complaint. The Lead Plaintiff filed an opposition to that motion on May 9, 2016, and the Company filed a reply brief on June 8, 2016. On February 13, 2017, the United States District Court for the Southern District of New York filed a Memorandum Opinion and Order dismissing the First Amended Complaint against the Company, the individual defendants and the underwriter defendants. The Plaintiff filed a motion with the Court to reconsider the Order of dismissal and reinstate the claims against the defendants on February 27, 2017. The Company anticipates filing an opposition brief by no later than March 13, 2017. The Company disputes these claims and is defending this matter vigorously, and is unable to estimate the amount of a potential loss or range of potential loss, if any. Legal fees are expensed in the period in which they are incurred. Leases The Company leases office facilities under operating leases. During the year ended December 31, 2016 , the Company entered into multiple new and amended operating leases for the purposes of sales and marketing, technology and development and engineering activities. Future minimum lease payments under non-cancelable operating leases as of December 31, 2016 for the fiscal years indicated are as follows (in thousands): Year Ending December 31, 2017 $ 2,946 2018 2,784 2019 2,160 2020 1,510 2021 1,254 Thereafter 1,772 Total minimum lease payments $ 12,426 Future minimum lease payments due under certain operating lease arrangements contain fixed rent increases and rent abatements over the term of the lease. Rent expense on these operating leases is recognized over the term of the lease on a straight-line basis. The excess of rent expense over lease payments made has been reported in accrued expenses and other current liabilities and other long-term liabilities in the consolidated balance sheets. As of December 31, 2015 and 2016 , deferred rent related to these leases totaled $1.0 million and $1.4 million , respectively. As of December 31, 2016 , the Company had outstanding letters of credit related to certain operating leases totaling $0.5 million . No amounts were drawn on these letters of credit. Total rent expense for the years ended December 31, 2014 , 2015 and 2016 was $1.6 million , $2.1 million and $2.9 million , respectively. Purchase Commitments The Company has $4.9 million of non-cancelable contractual commitments as of December 31, 2016 , primarily related to purchases of data, third-party data centers and other support services. Of these commitments, $3.6 million and $1.3 million are due within the next year and within the next two years, respectively. Indemnification Agreements In the ordinary course of business, the Company may provide indemnifications of varying scope and terms to customers, vendors, lessors, business partners and other parties with respect to certain matters, including, but not limited to, losses arising out of breach of such agreements, services to be provided by the Company or from intellectual property infringement claims made by third parties. In addition, the Company has entered into indemnification agreements with directors and certain officers and employees that will require the Company, among other things, to indemnify them against certain liabilities that may arise by reason of their status or service as directors, officers or employees. Under certain circumstances, the Company’s indemnification obligations may include the cost of advancing legal expenses and indemnifying its officers, directors and underwriters for costs arising out of the litigation described above under “Commitments and Contingencies — Litigation,” to the extent such costs are not covered by the Company’s directors’ and officers’ liability insurance. There are no claims that the Company is aware of that could have a material effect on the Company’s financial position, results of operations or cash flows.

Earnings Per Share

Earnings Per Share	12 Months Ended
	Dec. 31, 2016
Earnings Per Share [Abstract]
Earnings Per Share	Earnings Per Share Diluted loss per share is the same as basic loss per share for the years ended December 31, 2014 , 2015 and 2016 because the effects of potentially dilutive items were anti-dilutive given the Company’s net losses in those periods. The following securities have been excluded from the calculation of weighted-average common shares outstanding because the effect is anti-dilutive for the years ended December 31 : 2014 2015 2016 Convertible preferred stock: Series A 595,936 — — Series B 912,342 — — Series C 1,351,626 — — Series D 852,302 — — Common stock subject to repurchase 1,250 — — Lender warrants to purchase common stock 37,500 50,000 50,000 2015 ESPP — 48,220 36,983 Restricted stock units — — 536,100 Stock options 856,279 1,074,473 1,026,244 Total 4,607,235 1,172,693 1,649,327

Segment and Geographic Informat

Segment and Geographic Information	12 Months Ended
	Dec. 31, 2016
Segment Reporting [Abstract]
Segment and Geographic Information	Segment and Geographic Information Operating segments are defined as components of an enterprise for which discrete financial information is available that is evaluated regularly by the chief operating decision maker (“CODM”) for purposes of allocating resources and evaluating financial performance. The Company’s CODM, the Chief Executive Officer, reviews financial information presented on a consolidated basis for purposes of allocating resources and evaluating financial performance. The Company has one business activity, and there are no segment managers who are held accountable for operations, operating results or plans for levels or components below the consolidated unit level. Accordingly, the Company has determined that it has a single operating and reportable segment. For the year ended December 31, 2014 , approximately 96% of the Company’s long-lived assets were held and more than 99% of revenue was generated in the United States. For the year ended December 31, 2015 , approximately 98% of the Company’s long-lived assets were held and approximately 99% of revenue was generated in the United States. For the year ended December 31, 2016 , approximately 97% of the Company’s long-lived assets were held and approximately 99% of revenue was generated in the United States.

Related Party

Related Party	12 Months Ended
	Dec. 31, 2016
Related Party Transactions [Abstract]
Related Party	Related Party On August 15, 2015 , the Company entered into an advisor agreement with Kevin Dulsky, a non-employee board member. Mr. Dulsky agreed to consult with and advise the Company from time to time, at the Company’s request, on business development and strategic planning matters. Mr. Dulsky was paid an hourly fee for his services provided, in addition to reimbursement for reasonable expenses. The agreement allowed Mr. Dulsky or the Company to terminate the advisor relationship at any time by giving the other party fifteen days ’ notice. As of December 31, 2015, this advisor agreement had been terminated. For the year ended December 31, 2015, the Company incurred $0.02 million of expense related to this agreement that is classified in general and administrative expenses within the consolidated statement of operations. As of December 31, 2015, there were no amounts due to Mr. Dulsky under this agreement.

Summary of Significant Accoun23

Summary of Significant Accounting Policies (Policies)	12 Months Ended
	Dec. 31, 2016
Accounting Policies [Abstract]
Principles of Consolidation	Principles of Consolidation The consolidated financial statements include the accounts of the Company and its wholly-owned subsidiary and have been prepared in accordance with accounting principles generally accepted in the United States of America (“GAAP”). All intercompany accounts and transactions have been eliminated in consolidation.
Basis of Presentation	Basis of Presentation The consolidated financial statements have been prepared on a going concern basis, which contemplates the realization of assets and the satisfaction of liabilities in the normal course of business.
Use of Estimates	Use of Estimates The preparation of financial statements in conformity with GAAP requires management to make estimates and assumptions that affect the reported amounts in the consolidated financial statements and accompanying notes. The Company evaluates its estimates, including those related to its allowance for doubtful accounts, revenue recognition, internal-use software, stock-based compensation, income taxes and related valuation allowances and the fair value of common stock warrants. The Company bases its estimates on its 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. Actual results could differ from those estimates.
Cash and Cash Equivalents	Cash and Cash Equivalents The Company considers all highly liquid investments with a maturity of three months or less when purchased to be cash equivalents. Cash and cash equivalents consist of cash maintained in operating accounts.
Restricted Cash	Restricted Cash Restricted cash represents cash that is subject to contractual withdrawal restrictions and penalties. Restricted cash is classified within the consolidated balance sheets based on the timing of when the restrictions are expected to lapse. The Company presented restricted cash related to its debt agreement in the consolidated balance sheets based on timing of maturity.
Concentration of Credit Risk	Concentration of Credit Risk Financial instruments that potentially subject the Company to concentrations of credit risk consist principally of cash, cash equivalents and accounts receivable. All of the Company’s cash and cash equivalents are held at financial institutions that management believes to be of high credit quality. The Company’s cash and cash equivalent accounts exceed federally insured limits. The Company has not experienced any losses on cash and cash equivalents to date. To manage accounts receivable risk, the Company evaluates and monitors the creditworthiness of its customers.
Allowance for Doubtful Accounts	Allowance for Doubtful Accounts The Company extends credit to its customers without requiring collateral. Accounts receivable are stated at net realizable value. The Company utilizes the allowance method to provide for doubtful accounts based on management’s evaluation of the collectability of amounts due. The Company’s estimate is based on historical collection experience and the current status of accounts receivable. Historically, actual write-offs for uncollectible accounts have not significantly differed from the Company’s estimates.
Internal-Use Software Development Costs	Internal-Use Software Development Costs The Company capitalizes certain costs associated with software developed for internal use, primarily consisting of direct labor costs associated with creating the software. Software development projects generally include three stages: the preliminary project stage (all costs are expensed as incurred); the application development stage (certain costs are capitalized and certain costs are expensed as incurred); and the post-implementation/operation stage (all costs are expensed as incurred). Costs capitalized in the application development stage primarily include costs of designing, coding and testing the software. Capitalization of costs requires judgment in determining when a project has reached the application development stage and the period over which the Company expects to benefit from the use of that software. Once the software is placed in service, these capitalized costs are amortized using the straight-line method over the estimated useful life of the software.
Property, Equipment and Software, Net	Property, Equipment and Software, Net Property, equipment and software is recorded at cost, net of depreciation. Expenditures for major additions and improvements are capitalized. Depreciation and amortization are recognized over the estimated useful life of the related assets using the straight-line method. The depreciation and amortization periods for the Company’s significant property, equipment and software categories are as follows: Capitalized internal-use software costs 3 years Computer hardware and software 3 years Furniture and office equipment 3 years Leasehold improvements Lesser of remaining lease term or useful life Repairs and maintenance costs are expensed as incurred.
Impairment of Long-lived Assets	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 a 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.
Fair Value of Financial Instruments	Fair Value of Financial Instruments The carrying amounts of certain of the Company’s financial instruments, including cash and cash equivalents, restricted cash, accounts receivable, other current assets, accounts payable and accrued expenses and other current liabilities, approximate their respective fair values due to their short term nature. In order to determine the fair value of the stock options classified as liability awards, the Company used an option pricing model. These valuations require the input of subjective assumptions, including the estimated enterprise fair value, risk-free interest rate and expected stock price volatility. The risk-free interest rate assumption is based upon observed interest rates for constant maturity U.S. Treasury securities consistent with the term of the instruments. The expected stock price volatility assumption is based on historical volatilities for publicly traded stock of comparable companies over the term of the 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. In order to determine the fair value of the Lender Warrants, the Company used an option pricing model. These valuations require the input of subjective assumptions, including the estimated enterprise fair value, risk-free interest rate and expected stock price volatility. The risk-free interest rate assumption is based upon observed interest rates for constant maturity U.S. Treasury securities consistent with the term of the instruments. The expected stock price volatility assumption is based on historical volatilities for publicly traded stock of comparable companies over the term of the instruments.
Foreign Currency Translation and Transactions	Foreign Currency Translation and Transactions The consolidated financial statements of the Company’s foreign subsidiary are measured using the local currency as the functional currency. Assets and liabilities of foreign subsidiaries are translated at exchange rates in effect as of the balance sheet date. Revenues and expenses are translated at average exchange rates in effect during the period. Translation adjustments are recorded within accumulated other comprehensive loss, a separate component of stockholders’ equity, in the consolidated balance sheets.
Revenue Recognition	Revenue Recognition The Company generates revenue by delivering targeted advertising campaigns for customers through various channels, including display, mobile and video. The Company recognizes revenue when there is persuasive evidence of an arrangement, delivery has occurred or services have been provided, fees are fixed or determinable, and collection of fees is reasonably assured. Revenue arrangements are evidenced by a fully executed insertion order (“IO”). The IOs specify the delivery terms including the advertising format, the contracted number of advertising impressions to be delivered, the agreed upon rate for each delivered impression, generally on a cost-per-thousand basis, and the fixed period of time for delivery. The IOs typically have a term of less than three months and are cancelable at any time. The Company recognizes revenue in the period in which the impressions are served, limited to the contracted number of impressions as specified in the IO. The Company determines collectability by performing a credit evaluation for new customers and by monitoring its existing customers’ accounts receivable balances. The Company does not typically receive upfront payments from its customers. In the normal course of business, the Company contracts either directly with advertisers or advertising agencies on behalf of their advertiser clients. The determination of whether revenue should be reported on a gross or net basis is based on an assessment of whether the Company is acting as the principal or an agent in the transaction. In determining whether the Company acts as the principal or an agent, the Company follows the accounting guidance for principal-agent considerations. While no one factor is determined to be individually conclusive, indicators that an entity is acting as a principal include if the Company (i) is the primary obligor in the arrangement; (ii) has certain inventory risk; (iii) has latitude in establishing pricing; (iv) adds meaningful value to the service; (v) has discretion in supplier selection; (vi) is involved in the determination of the service specifications; or (vii) has credit risk. The Company recognizes revenue on a gross basis primarily based on the Company’s determination that it is subject to the risk of fluctuating costs from its media vendors, has latitude in establishing prices with its customers, has discretion in selecting media vendors when fulfilling a customer’s advertising campaign, and has credit risk. The Company may enter into multiple element arrangements for the delivery of more than one advertising placement to be delivered at the same time, or within close proximity of one another. When entering into an arrangement that includes multiple elements, the Company determines whether the arrangement should be divided into separate units of accounting and how the arrangement consideration should be measured and allocated among the separate units of accounting. An element qualifies as a separate unit of accounting when the delivered element has standalone value to the customer. The Company sells advertising placements on a standalone basis and thus has determined that each advertising placement in multiple element arrangements represents a separate unit of accounting. The Company allocates arrangement consideration in multiple element arrangements at the inception of an arrangement to all deliverables based on the relative selling price method in accordance with the selling price hierarchy, which includes: (1) vendor-specific objective evidence (“VSOE”), if available; (2) third-party evidence (“TPE”), if VSOE is not available; and (3) best estimate of selling price (“BESP”), if neither VSOE nor TPE is available. The Company has been unable to establish VSOE or TPE, and therefore, uses BESP in its allocation of arrangement consideration. The Company determines BESP for its deliverables by considering a number of factors including, but not limited to, the price lists used by the Company’s sales team in pricing negotiations, historical average and median pricing achieved in prior contractual customer arrangements and input from the Company’s sales operation department regarding what it believes the deliverables could be sold for on a stand-alone basis. The Company allocates consideration in all multiple element arrangements based on the relative fair value of the deliverables and recognizes revenue as services are delivered, assuming all other revenue recognition criteria have been met.
Cost of Revenue	Cost of Revenue Traffic Acquisition Costs Traffic acquisition costs consist of media costs for advertising impressions purchased from real-time bidding exchanges, which are expensed as incurred. The Company is billed by the advertising exchanges on a monthly basis for actual advertising impressions acquired. Other Cost of Revenue Other cost of revenue includes third-party data center and other advertisement-serving costs, depreciation of data center equipment, amortization of capitalized internal-use software cost for revenue-producing technologies, purchases of third-party data for specific marketing campaigns and salaries and related costs for the Company’s personnel dedicated to executing the Company’s advertising campaigns.
Research and Development	Research and Development Research and development expenses include costs associated with the ongoing development of the Company’s technology, including compensation and employee benefits and allocated costs associated with the Company’s engineering and research and development departments, as well as costs for contracted services and supplies.
Advertising and Marketing	Advertising and Marketing Advertising and marketing costs are expensed as incurred and totaled $3.7 million , $6.1 million and $3.9 million for the years ended December 31, 2014 , 2015 and 2016 , respectively.
Stock-Based Compensation	Stock-Based Compensation The Company accounts for stock options and restricted stock units (“RSU’s”) granted to employees and shares to be issued under its employee stock purchase plan (“ESPP”) based on their estimated fair values on the date of grant. The fair value of each stock option granted and share to be issued under its ESPP is estimated using the Black-Scholes option pricing model. The fair value of RSU’s is estimated based on the closing price of the underlying common stock on the date of grant. Stock-based compensation expense is recognized on a straight-line basis over the requisite service or offering period, net of estimated forfeitures. 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. The Company uses the simplified method due to the lack of sufficient historical exercise data to provide a reasonable basis upon which to otherwise estimate the expected life of the stock options. Expected volatility is based on historical volatilities for publicly traded stock of comparable companies over the estimated expected life of the stock options. The Company assumes no dividend yield, which is consistent with the Company’s history of not paying dividends. The fair value of the “look back” option for 2015 ESPP shares issued from the offering period is estimated using: (1) a 15% discount on the purchase of the stock; (2) 85% of the fair value of the call option; and (3) 15% of the fair value of the put option.
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 consolidated financial statement carrying amounts of existing assets and liabilities and their respective tax basis, 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 statements of operations in the period when enacted. 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 assessment of whether or not a valuation allowance is required often requires significant judgment, including the long-range forecast of future taxable income and the evaluation of tax planning initiatives. Adjustments to the deferred tax valuation allowances are made to earnings in the period when such assessments are made.
Basic and Diluted Loss per Common Share	Basic and Diluted Loss per Common Share Prior to the IPO, the Company used the two-class method to compute net loss per common share because the Company had issued securities, other than common stock, that contractually entitled the holders to participate in dividends and earnings of the Company. The two-class method requires earnings for the period to be allocated between common stock and participating securities based upon their respective rights to receive distributed and undistributed earnings. Each series of the Company’s convertible preferred stock were entitled to participate in distributions that were made to common stockholders, when and if declared by the board of directors, and therefore, were considered participating securities. Due to the net loss for the year ended December 31, 2014 , basic and diluted loss per share were the same, as the effect of potentially dilutive securities would have been anti-dilutive. Subsequent to the completion of the IPO, the Company no longer has outstanding participating securities. Therefore, the Company calculates net loss per basic share by dividing net loss by the weighted-average number of shares outstanding during the reporting period. The Company calculates net loss per diluted share by dividing net loss by the weighted-average number of shares outstanding during the reporting period plus the effects of any dilutive common stock-based instruments.
Recently Adopted Accounting Pronouncements and Recent Accounting Pronouncements Not Yet Adopted	Recently Adopted Accounting Pronouncements In April 2015, the FASB issued ASU 2015-03, Simplifying the Presentation of Debt Issuance Costs . This accounting standards update is to simplify the presentation of debt issuance cost. This new guidance requires that debt issuance cost related to a recognized debt liability be presented in the balance sheet as a direct deduction from the carrying amount of that debt liability, consistent with the treatment of debt discounts. The accounting standards update does not affect the recognition and measurement guidance for debt issuance costs. In August 2015, the FASB issued ASU 2015-15, Presentation and Subsequent Measurement of Debt Issuance Costs Associated with Line-of-Credit Arrangements . This accounting standards update states that given the absence of authoritative guidance within ASU 2015-03 for debt issuance costs related to line of credit arrangements, the Securities and Exchange Commission would not object to an entity deferring and presenting debt issuance costs as an asset and subsequently amortizing the debt issuance costs ratably over the term of the line of credit arrangement, regardless of whether there are any outstanding borrowings on the line of credit arrangement. The Company adopted ASU 2015-03, effective January 1, 2016, on a retrospective basis. The adoption of these pronouncements did not have a material impact on the Company’s consolidated results of operations, financial position or cash flows. In August 2014, the FASB issued ASU 2014-15, Disclosure of Uncertainties about an Entity’s Ability to Continue as a Going Concern . This guidance addresses management’s responsibility to evaluate whether there is substantial doubt about an entity’s ability to continue as a going concern and to provide related footnote disclosures. Management’s evaluation should be based on relevant conditions and events that are known and reasonably knowable at the date that the financial statements are issued. ASU 2014-15 is effective for annual periods ending after December 15, 2016, and for interim periods within annual periods ending after December 15, 2016. Although early adoption was permitted, the Company did not early adopt this standard. The Company adopted ASU 2014-15 effective December 31, 2016. The adoption did not have a material effect on the Company’s consolidated financial statements, however, the Company has expanded its disclosures in the related notes thereto. In November 2015, the FASB issued ASU 2015-17, Balance Sheet Classification of Deferred Taxes. This accounting standards update simplifies the presentation of deferred income taxes by eliminating the current requirement for an entity to separate deferred income tax liabilities and assets into current and noncurrent amounts in a classified statement of financial position. ASU 2015-17 requires an entity to classify deferred income tax liabilities and assets, as well as any related valuation allowance, as noncurrent within a classified balance sheet. This accounting standards update is effective for interim or annual periods beginning after December 15, 2016, and can be applied retrospectively or prospectively. The Company elected to early adopt ASU 2015-17, effective December 31, 2016, on a retrospective basis. The Company’s now has, in each taxable jurisdiction, one deferred tax asset and liability, along with any related valuation allowance, classified as noncurrent on its consolidated balance sheets. The adoption did not have a material effect on the Company’s consolidated results of operations, financial position or cash flows as the Company has a full valuation allowance on deferred tax assets due to its historical losses from operations. Recent Accounting Pronouncements Not Yet Adopted In May 2014, the FASB issued ASU 2014-09, Revenue from Contracts with Customers . The new standard provides a single principles-based, five-step model to be applied to all contracts with customers, which steps are to (1) identify the contract(s) with the customer; (2) identify the performance obligations in the contract; (3) determine the transaction price; (4) allocate the transaction price to the performance obligations in the contract; and (5) recognize revenue when each performance obligation is satisfied. More specifically, revenue will be recognized when promised goods or services are transferred to the customer in an amount that reflects the consideration expected in exchange for those goods or services. This guidance states that an entity should recognize revenue to depict the transfer of promised goods or services to customers in an amount that reflects the consideration to which the entity expects to be entitled in exchange for those goods or services. In August 2015, the FASB issued ASU 2015-14, which defers the effective date of ASU 2014-09 for all entities by one year. In March 2016, the FASB issued ASU 2016-08, which clarifies the implementation guidance on principal versus agent considerations. In April 2016, the FASB issued ASU 2016-10, which clarifies the implementation guidance on identifying performance obligations and licensing. In May 2016, the FASB issued ASU 2016-11, Rescission of SEC Guidance Because of Accounting Standards Updates 2014-09 and 2014-16 Pursuant to Staff Announcements at the March 3, 2016 EITF Meeting , which rescinds SEC paragraphs pursuant to SEC staff announcements. These rescissions include changes to topics pertaining to accounting for shipping and handling fees and costs and accounting for consideration given by a vendor to a customer. In May 2016, the FASB issued ASU 2016-12, Narrow-Scope Improvements and Practical Expedients , which amends certain aspects of the new revenue recognition standard pursuant to ASU 2014-09. In December 2016, the FASB issued ASU 2016-20, which contains amendments that affect narrow aspects of the new revenue recognition guidance. ASU 2014-09, as amended by ASU 2015-14, is effective for interim or annual periods beginning after December 15, 2017. Early adoption of the standard is permitted, but not before the original effective date. The Company plans to adopt ASU 2014-09 as of January 1, 2018. The Company enters into contracts, or IOs, with customers either directly or through advertising agencies that act on behalf of its customers to deliver targeted digital marketing campaigns through various channels. Executed IOs typically have a term of less than three months and are cancelable at any time. The Company prices its marketing campaigns based on the number of advertising impressions and recognizes revenue as they are delivered. The Company is permitted to use either the retrospective or the modified retrospective method when adopting ASU 2014-09. The Company is currently evaluating the impact of this standard on its consolidated results of operations, financial position, cash flows and disclosures, and has not yet concluded on the method of adoption. In February 2016, the FASB issued ASU 2016-02, Leases (Topic 842) . The purpose of this guidance is to increase transparency and comparability among organizations by recognizing lease assets and lease liabilities on the balance sheet and disclosing key information about leasing arrangements. This guidance supersedes previous accounting guidance under Topic 840. Under ASU 2016-02, a lessee will be required to recognize assets and liabilities for the rights and obligations created by leases for leases with lease terms of more than 12 months. Lessor accounting remains substantially similar to current GAAP. In addition, disclosures of leasing activities are to be expanded to include qualitative along with specific quantitative information. ASU 2016-02 is effective for interim or annual periods beginning after December 15, 2018 and early adoption is permitted. This standard requires lessees and lessors to recognize and measure leases at the beginning of the earliest period presented using a modified retrospective approach. The Company does not expect to early adopt this guidance and is currently evaluating the impact of the adoption of this guidance on its consolidated results of operations, financial position and cash flows. In March 2016, the FASB issued ASU 2016-09, Improvements to Employee Share-Based Payment Accounting . ASU 2016-09 simplifies several aspects of the accounting for share-based payment transactions, including the income tax consequences, classification of awards as either equity or liabilities and classification on the statement of cash flows. ASU 2016-09 is effective for interim or annual periods beginning after December 15, 2016 and early adoption is permitted. The Company did not early adopt this standard and does not expect that adoption will have a material effect on its consolidated results of operations, financial position and cash flows. In August 2016, the FASB issued ASU 2016-15, Classification of Certain Cash Receipts and Cash Payments . This new standard provides guidance related to eight specific cash flow issues, with the objective of reducing diversity in practice of how certain cash receipts and payments are presented and classified in the statement of cash flows. ASU 2016-15 is effective for interim or annual periods beginning after December 15, 2017 and early adoption is permitted. ASU 2016-15 must be applied retrospectively, unless it is impracticable to do so, in which case the amendments would be applied prospectively as of the earliest date practicable. The Company does not expect to early adopt this guidance and is currently evaluating the impact of the adoption of this guidance on its consolidated results of operations, financial position and cash flows. In November 2016, the FASB issued ASU 2016-18, Restricted Cash . The purpose of this guidance is to reduce the diversity in practice that exists in the classification and presentation of changes in restricted cash on the statement of cash flows. This guidance requires that a statement of cash flows explain the change during the period in the total of cash, cash equivalents and amounts generally described as restricted cash or restricted cash equivalents. Therefore, amounts generally described as restricted cash and restricted cash equivalents should be included with cash and cash equivalents when reconciling the beginning-of-period and end-of-period total amounts shown on the statement of cash flows. ASU 2016-18 is effective for interim or annual periods beginning after December 15, 2017 and early adoption is permitted. This guidance must be applied retrospectively. The Company is currently evaluating the impact of the adoption of this guidance on its consolidated results of operations, financial position and cash flows.

Summary of Significant Accoun24

Summary of Significant Accounting Policies (Tables)	12 Months Ended
	Dec. 31, 2016
Accounting Policies [Abstract]
Schedule of changes in the allowance for doubtful accounts	The following table presents the changes in the allowance for doubtful accounts for the years ended December 31 (in thousands): 2014 2015 2016 Allowance for doubtful accounts: Balance, beginning of period $ 716 $ 179 $ 102 Add: adjustment for bad debts (211 ) 205 358 Less: write-offs, net of recoveries (326 ) (282 ) (170 ) Balance, end of period $ 179 $ 102 $ 290
Schedule of property, equipment and software, net	The depreciation and amortization periods for the Company’s significant property, equipment and software categories are as follows: Capitalized internal-use software costs 3 years Computer hardware and software 3 years Furniture and office equipment 3 years Leasehold improvements Lesser of remaining lease term or useful life Property, equipment and software, net consisted of the following as of December 31 (in thousands): 2015 2016 Capitalized internal-use software costs $ 14,800 $ 21,993 Computer hardware and software 16,028 18,091 Furniture and office equipment 340 440 Leasehold improvements 863 1,967 Total 32,031 42,491 Less: accumulated depreciation (12,646 ) (22,366 ) Property, equipment and software, net $ 19,385 $ 20,125

Fair Value Measurements (Tables

Fair Value Measurements (Tables)	12 Months Ended
	Dec. 31, 2016
Fair Value Disclosures [Abstract]
Schedule of fair value of financial instruments measured on recurring basis	The following table sets forth the Company’s financial instruments that were measured at fair value on a recurring basis as of December 31, 2015 by level within the fair value hierarchy (in thousands): December 31, 2015 Fair Value Level 1 Level 2 Level 3 Assets: Cash and cash equivalents — Money Market Fund $ 18,612 $ 18,612 $ — $ —
Schedule of changes in instruments measured at fair value on recurring basis	The following table presents the changes in the recorded liability associated with certain of the Company’s stock option awards which, as described above, have been accounted for as liability-based awards during the years ended December 31 (in thousands): 2014 2015 Balance as of January 1 $ — $ 461 Issuance of stock options 410 — Change in fair value of stock options classified as liability awards 51 (173 ) Reclassification of stock options classified as liability awards to equity — (288 ) Balance as of December 31 $ 461 $ — The following table presents the changes in the Company’s Lender Warrants measured at fair value on a recurring basis during the years ended December 31 (in thousands): 2014 2015 Balance as of January 1 $ — $ 1,614 Issuance of warrants 943 — Change in fair value of warrants liability 671 (482 ) Reclassification of warrants to equity — (1,132 ) Balance as of December 31 $ 1,614 $ —
Schedule of assumptions used	The following table summarizes the assumptions used for estimating the fair value of the stock options classified as liability awards for the years ended December 31: 2014 2015 Risk-free interest rate 1.61% - 2.00% 1.46% - 1.67% Expected term (years) 4.85 - 6.08 4.74 - 6.03 Expected volatility 56% - 58% 51% - 53% Dividend yield —% —% The following table summarizes the assumptions used for estimating the fair value of the Lender Warrants for the years ended December 31: 2014 2015 Risk-free interest rate 2.13% - 2.58% 1.97% Expected term (years) 9.45 - 10.00 9.34 Expected volatility 57% - 58% 58% Dividend yield —% —%

Property, Equipment and Softw26

Property, Equipment and Software, Net (Tables)	12 Months Ended
	Dec. 31, 2016
Property, Plant and Equipment [Abstract]
Schedule of property, equipment and software, net	The depreciation and amortization periods for the Company’s significant property, equipment and software categories are as follows: Capitalized internal-use software costs 3 years Computer hardware and software 3 years Furniture and office equipment 3 years Leasehold improvements Lesser of remaining lease term or useful life Property, equipment and software, net consisted of the following as of December 31 (in thousands): 2015 2016 Capitalized internal-use software costs $ 14,800 $ 21,993 Computer hardware and software 16,028 18,091 Furniture and office equipment 340 440 Leasehold improvements 863 1,967 Total 32,031 42,491 Less: accumulated depreciation (12,646 ) (22,366 ) Property, equipment and software, net $ 19,385 $ 20,125

Accrued Expenses and Other Cu27

Accrued Expenses and Other Current Liabilities (Tables)	12 Months Ended
	Dec. 31, 2016
Payables and Accruals [Abstract]
Schedule of accrued expenses	Accrued expenses consisted of the following as of December 31 (in thousands): 2015 2016 Accrued commissions $ 2,713 $ 2,517 Accrued bonuses 1,190 2,037 Accrued salaries, wages, benefits and related costs 1,190 371 Accrued credit card purchases 645 597 Other accrued expenses and current liabilities 2,648 3,878 Accrued expenses and other current liabilities $ 8,386 $ 9,400

Common and Preferred Stock (Tab

Common and Preferred Stock (Tables)	12 Months Ended
	Dec. 31, 2016
Stockholders' Equity, Number of Shares, Par Value and Other Disclosures [Abstract]
Schedule of common stock reserved for issuance	The Company’s shares of common stock reserved for issuance as of December 31, 2015 and 2016 were as follows: 2015 2016 Lender warrants to purchase common stock 50,000 50,000 Stock options outstanding 1,074,473 1,026,244 Unvested restricted stock units — 536,100 Possible future issuance under equity incentive plan 380,460 189,513 Possible future issuance under employee stock purchase plan 60,318 66,823 Total shares reserved 1,565,251 1,868,680

Convertible Preferred Stock (Ta

Convertible Preferred Stock (Tables)	12 Months Ended
	Dec. 31, 2016
Temporary Equity, Other Disclosures [Abstract]
Schedule of issuances of convertible preferred stock	The following table summarizes the issuances of convertible preferred stock subject to conversion as of the IPO completion: Number of Shares Authorized Number of Shares Outstanding Original Issue and Conversion Price per Share Series A convertible preferred stock 621,626 595,936 $ 2.328 Series B convertible preferred stock 912,342 912,342 $ 3.38624 Series C convertible preferred stock 1,351,626 1,351,626 $ 5.9192 Series D convertible preferred stock 852,312 852,302 $ 15.2528 Total convertible preferred stock 3,737,906 3,712,206
Summary of activity for the convertible preferred stock	The following table presents a summary of activity for the convertible preferred stock issued and outstanding for the years ended December 31, 2014 and 2015 (in thousands): Convertible Preferred Stock Series A Series B Series C Series D Total Amount Balance as of December 31, 2014 $ 1,387 $ 3,089 $ 8,000 $ 13,000 $ 25,476 Conversion to common stock upon IPO (1,387 ) (3,089 ) (8,000 ) (13,000 ) (25,476 ) Balance as of December 31, 2015 $ — $ — $ — $ — $ —

Stock-Based Compensation (Table

Stock-Based Compensation (Tables)	12 Months Ended
	Dec. 31, 2016
Disclosure of Compensation Related Costs, Share-based Payments [Abstract]
Schedule of stock-based compensation expense	Stock-based compensation expense related to the 2015 ESPP is included in the following line items in the consolidated statements of operations for the years ended December 31 (in thousands): 2015 2016 Other cost of revenue $ 17 $ 4 Sales and marketing 177 64 Research and development 244 125 General and administrative 66 27 $ 504 $ 220 Stock-based compensation expense related to RSU’s is included in the following line items in the consolidated statements of operations for the year ended December 31(in thousands): 2016 Other cost of revenue $ 27 Sales and marketing 104 Research and development 294 General and administrative 163 $ 588 Stock-based compensation expense related to stock options is included in the following line items in the consolidated statements of operations for the years ended December 31 (in thousands): Year Ended December 31, 2014 (1) 2015 (2) 2016 Other cost of revenue $ 20 $ 75 $ 75 Sales and marketing 505 720 719 Research and development 756 1,114 1,268 General and administrative 1,058 1,444 1,539 $ 2,339 $ 3,353 $ 3,601 (1) Stock-based compensation expense included an unfavorable $0.5 million fair value adjustment related to stock option liability awards during the year ended December 31, 2014 . See Note 3 for further description of the accounting treatment for these awards. (2) Stock-based compensation expense included a favorable $0.2 million fair value adjustment related to stock option liability awards prior to reclassification to additional paid-in capital during the year ended December 31, 2015 .
Summary of the assumptions used for estimating the fair value of stock options granted	The following table summarizes the assumptions used for estimating the fair value of stock options granted to employees for the years ended December 31 : 2014 2015 2016 Risk-free interest rate 1.32% - 2.04% 1.57% - 1.94% 1.16% - 2.10% Expected term (years) 4.00 - 6.08 6.03 - 6.08 6.08 Expected volatility 56% - 60% 46% - 59% 46% - 47% Dividend yield —% —% —%
Summary of stock option activity	The following table summarizes the Company’s stock option activity for the year ended December 31, 2016 : Number of Options Weighted- Average Exercise Price Weighted- Average Remaining Contractual Term Aggregate Intrinsic Value (in years) (in thousands) Outstanding balance at January 1, 2016 1,074,473 $ 30.69 8.39 $ 500 Granted 133,760 8.44 Exercised (31,125 ) 3.65 Cancelled (150,864 ) 29.84 Outstanding balance at December 31, 2016 1,026,244 $ 28.73 7.65 $ 299 Exercisable at December 31, 2016 565,043 $ 30.65 6.91 $ 299 Vested and expected to vest at December 31, 2016 986,301 $ 29.17 7.60 $ 299
Summary of options outstanding and vested by exercise price range	The following table provides a summary of options outstanding and vested as of December 31, 2016 : Options Outstanding Options Exercisable Exercise Prices Number of Options Weighted Average Exercise Price Weighted- Average Remaining Contractual Term (in Years) Number of Options Weighted Average Exercise Price Weighted- $1.36 - $15.00 313,087 $ 7.11 6.97 175,117 $ 6.10 5.10 $15.01 - $30.00 287,808 20.26 8.52 111,696 20.35 8.31 $30.01 - $45.00 59,336 36.48 8.02 30,116 36.61 7.75 $45.01 - $60.72 366,013 52.63 7.49 248,114 51.89 7.46 1,026,244 $ 28.73 7.65 565,043 $ 30.65 6.91
Summary of the assumptions used for estimating the fair value of shares to be granted under the 2015 ESPP	The following table summarizes the assumptions used in the Black-Scholes option pricing model for estimating the fair value of shares to be granted under the 2015 ESPP for the offering periods during the year ended December 31 : 2015 2016 Risk-free interest rate 0.10% - 0.27% 0.41% - 0.50% Expected term (years) 0.50 - 0.59 0.50 Expected volatility 55% - 61% 41% - 43% Dividend yield —% —%
Summary of restricted stock unit activity	The following table summarizes the Company’s restricted stock unit activity for the year ended December 31, 2016 : Number of Weighted- Nonvested balance at January 1, 2016 — $ — Granted 566,420 8.87 Vested — — Forfeited (30,320 ) 8.87 Nonvested balance at December 31, 2016 536,100 $ 8.87

Income Taxes (Tables)

Income Taxes (Tables)	12 Months Ended
	Dec. 31, 2016
Income Tax Disclosure [Abstract]
Components of loss before income taxes	The following table presents domestic and foreign components of loss before income taxes for the periods presented (in thousands of dollars): Year Ended December 31, 2014 2015 2016 Domestic $ (11,222 ) $ (19,917 ) $ (15,086 ) International (1,767 ) (2,536 ) (2,765 ) Total $ (12,989 ) $ (22,453 ) $ (17,851 )
Reconciliation of differences between statutory U.S. federal and effective income tax rate	Taxes computed at the statutory U.S. federal income tax rate of 34% are reconciled to the provision for income taxes as follows (in thousands of dollars): Year Ended December 31, 2014 2015 2016 Effective tax rate 0 % 0 % 0 % Statutory rate of 34% $ (4,416 ) $ (7,634 ) $ (6,069 ) State taxes, net of federal benefit (256 ) (615 ) (388 ) Foreign rate differential 245 346 455 Stock-based compensation permanent differences 464 836 785 Meals and entertainment permanent differences 232 385 376 Miscellaneous permanent differences 32 165 264 Warrant fair market value adjustment 229 (59 ) — Other adjustments 474 (3 ) (96 ) Change in valuation allowance 2,996 6,579 4,673 Provision for income taxes $ — $ — $ —
Components of deferred tax assets (liabilities)	Components of the deferred tax assets were as follows (in thousands of dollars): December 31, 2015 2016 Accrued expenses $ 882 $ 1,303 Stock-based compensation 854 1,611 Future benefit of carry forward losses 17,946 21,742 Other accruals 488 678 Valuation allowance (14,871 ) (19,544 ) Total deferred tax asset $ 5,299 $ 5,790 Components of deferred tax liabilities were as follows (in thousands of dollars): December 31, 2015 2016 Amortization $ (3,688 ) $ (4,482 ) Depreciation (1,591 ) (1,308 ) Other accruals (20 ) — Total deferred tax liability $ (5,299 ) $ (5,790 ) Net deferred tax assets (liabilities) $ — $ —

Commitments and Contingencies (

Commitments and Contingencies (Tables)	12 Months Ended
	Dec. 31, 2016
Commitments and Contingencies Disclosure [Abstract]
Schedule of future minimum lease payments	Future minimum lease payments under non-cancelable operating leases as of December 31, 2016 for the fiscal years indicated are as follows (in thousands): Year Ending December 31, 2017 $ 2,946 2018 2,784 2019 2,160 2020 1,510 2021 1,254 Thereafter 1,772 Total minimum lease payments $ 12,426

Earnings Per Share (Tables)

Earnings Per Share (Tables)	12 Months Ended
	Dec. 31, 2016
Earnings Per Share [Abstract]
Summary of anti-dilutive securities which are excluded from the calculation of weighted average common shares outstanding	The following securities have been excluded from the calculation of weighted-average common shares outstanding because the effect is anti-dilutive for the years ended December 31 : 2014 2015 2016 Convertible preferred stock: Series A 595,936 — — Series B 912,342 — — Series C 1,351,626 — — Series D 852,302 — — Common stock subject to repurchase 1,250 — — Lender warrants to purchase common stock 37,500 50,000 50,000 2015 ESPP — 48,220 36,983 Restricted stock units — — 536,100 Stock options 856,279 1,074,473 1,026,244 Total 4,607,235 1,172,693 1,649,327

Description of Business - Organ

Description of Business - Organization (Details)	Dec. 31, 2016office
United Kingdom
Entity Location [Line Items]
Number of offices	1

Description of Business - Initi

Description of Business - Initial Public Offering (Details) - USD ($) $ / shares in Units, $ in Thousands	Mar. 11, 2015	Dec. 31, 2016	Dec. 31, 2015	Dec. 31, 2014
Class of Stock [Line Items]
Proceeds from the issuance of common stock in initial public offering, net of underwriting discounts and commissions		$ 0	$ 69,518	$ 0
Deferred offering costs reclassified to additional paid-in capital		$ 0	$ 3,782	$ 0
IPO
Class of Stock [Line Items]
Shares issued during period	1,625,000
Shares issued price per share (in usd per share)	$ 46
Proceeds from the issuance of common stock in initial public offering, net of underwriting discounts and commissions	$ 69,500
Deferred offering costs reclassified to additional paid-in capital	$ 3,800
Shares issued upon conversion	3,712,206

Description of Business - Rever

Description of Business - Reverse Stock Split (Details)	Apr. 25, 2016	Feb. 20, 2015
Organization, Consolidation and Presentation of Financial Statements [Abstract]
Stock split conversion ratio	0.25	0.50

Description of Business - Stock

Description of Business - Stock Repurchase Program (Details) - Common Stock - USD ($) $ / shares in Units, $ in Millions	12 Months Ended
	Dec. 31, 2016	Mar. 04, 2016
Equity, Class of Treasury Stock [Line Items]
Amount of stock repurchase program authorized (up to)		$ 4
Number of shares repurchased (in shares)	15,197
Weighted average price per share of shares repurchased (in usd per share)	$ 8.19
Amount available for common stock repurchases under the program	$ 3.9

Summary of Significant Accoun38

Summary of Significant Accounting Policies - Restricted Cash (Details) - USD ($)	Dec. 31, 2016	Mar. 07, 2016	Dec. 31, 2015	Jun. 12, 2014
Compensating Balances [Line Items]
Restricted cash, short-term	$ 0		$ 1,861,000
Amended New Loan and Security Agreement
Compensating Balances [Line Items]
Restricted cash, short-term			1,900,000
Available borrowing capacity	$ 5,000,000		3,100,000
Amended New Loan and Security Agreement | Minimum
Compensating Balances [Line Items]
Minimum amount required to be maintained by the company at all times		$ 5,000,000	$ 5,000,000	$ 5,000,000

Summary of Significant Accoun39

Summary of Significant Accounting Policies - Concentration of Credit Risk (Details) - Major Customer One - Accounts Receivable - Customer Concentration Risk	12 Months Ended
	Dec. 31, 2016customer
Concentration Risk [Line Items]
Concentration risk, number of customers	1
Concentration risk, percentage of accounts receivable	12.00%

Summary of Significant Accoun40

Summary of Significant Accounting Policies - Allowance for Doubtful Accounts (Details) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2016	Dec. 31, 2015	Dec. 31, 2014
Allowance for doubtful accounts:
Balance, beginning of period	$ 102	$ 179	$ 716
Add: adjustment for bad debts	358	205	(211)
Less: write-offs, net of recoveries	(170)	(282)	(326)
Balance, end of period	$ 290	$ 102	$ 179

Summary of Significant Accoun41

Summary of Significant Accounting Policies - Internal-Use Software Development Costs (Details) - Capitalized internal-use software costs - USD ($) $ in Millions	12 Months Ended
	Dec. 31, 2016	Dec. 31, 2015	Dec. 31, 2014
Internal-Use Software Development Costs
Capitalized development costs	$ 7.2	$ 6.5	$ 4
Amortization expense	5	2.4	$ 1.3
Net book value	$ 12	$ 9.8

Summary of Significant Accoun42

Summary of Significant Accounting Policies - Property, Equipment and Software (Details)	12 Months Ended
	Dec. 31, 2016
Capitalized internal-use software costs
Property, Plant and Equipment [Line Items]
Estimated useful life of property, equipment and software	3 years
Computer hardware and software
Property, Plant and Equipment [Line Items]
Estimated useful life of property, equipment and software	3 years
Furniture and office equipment
Property, Plant and Equipment [Line Items]
Estimated useful life of property, equipment and software	3 years

Summary of Significant Accoun43

Summary of Significant Accounting Policies - Revenue Recognition (Details)	12 Months Ended
	Dec. 31, 2016
Accounting Policies [Abstract]
Fully executed IOs, term (less than)	3 months

Summary of Significant Accoun44

Summary of Significant Accounting Policies - Advertising and Marketing (Details) - USD ($) $ in Millions	12 Months Ended
	Dec. 31, 2016	Dec. 31, 2015	Dec. 31, 2014
Accounting Policies [Abstract]
Advertising and marketing costs	$ 3.9	$ 6.1	$ 3.7

Fair Value Measurements - Fair

Fair Value Measurements - Fair Value of Financial Instruments Measured on a Recurring Basis (Details) - Recurring - Money Market Fund $ in Thousands	Dec. 31, 2015USD ($)
Assets:
Cash and cash equivalents — Money Market Fund	$ 18,612
Level 1
Assets:
Cash and cash equivalents — Money Market Fund	18,612
Level 2
Assets:
Cash and cash equivalents — Money Market Fund	0
Level 3
Assets:
Cash and cash equivalents — Money Market Fund	$ 0

Fair Value Measurements - Commo

Fair Value Measurements - Common Stock Warrants (Details) - USD ($)	12 Months Ended
	Dec. 31, 2016	Dec. 31, 2015	Dec. 31, 2014	Feb. 12, 2015	Dec. 16, 2014	Jun. 12, 2014
Class of Warrant or Right [Line Items]
Change in fair value of warrants	$ 0	$ (482,000)	$ 671,000
Amended Mezzanine Loan and Security Agreement
Class of Warrant or Right [Line Items]
Change in fair value of warrants	$ 0	$ (500,000)	$ 700,000
Amended Mezzanine Loan and Security Agreement | Amended Term Loan - First Tranche
Class of Warrant or Right [Line Items]
Number of shares of common stock that may be purchased based on lender warrants issued						25,000
Exercise price of warrants (in usd per share)						$ 45.44
Fair value of warrants						$ 900,000
Total face amount of debt						10,000,000
Amended Mezzanine Loan and Security Agreement | Amended Term Loan - Second Tranche
Class of Warrant or Right [Line Items]
Number of shares of common stock that may be purchased based on lender warrants issued					12,500
Exercise price of warrants (in usd per share)					$ 45.44
Borrowing capacity remaining						$ 5,000,000
Total face amount of debt					$ 5,000,000
Amended Mezzanine Loan and Security Agreement | Amended Term Loan - 2015 Term Loan
Class of Warrant or Right [Line Items]
Number of shares of common stock that may be purchased based on lender warrants issued				12,500
Exercise price of warrants (in usd per share)				$ 60.72
Fair value of warrants				$ 300,000
Total face amount of debt				$ 5,000,000

Fair Value Measurements - Chang

Fair Value Measurements - Changes in Lender Warrants (Details) - Lender Warrants - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2015	Dec. 31, 2014
Fair Value, Liabilities Measured on Recurring Basis, Unobservable Input Reconciliation, Calculation [Roll Forward]
Balance as of January 1	$ 1,614	$ 0
Issuance of warrants	0	943
Change in fair value of warrants liability	(482)	671
Reclassification of warrants to equity	(1,132)	0
Balance as of December 31	$ 0	$ 1,614

Fair Value Measurements - Fai48

Fair Value Measurements - Fair Value Assumptions of Lender Warrants (Details) - Lender Warrants	12 Months Ended
	Dec. 31, 2015	Dec. 31, 2014
Fair Value Measurements, Recurring and Nonrecurring, Valuation Techniques [Line Items]
Risk-free interest rate	1.97%
Expected term	9 years 4 months 2 days
Expected volatility	58.00%
Dividend yield	0.00%	0.00%
Minimum
Fair Value Measurements, Recurring and Nonrecurring, Valuation Techniques [Line Items]
Risk-free interest rate		2.13%
Expected term		9 years 5 months 12 days
Expected volatility		57.00%
Maximum
Fair Value Measurements, Recurring and Nonrecurring, Valuation Techniques [Line Items]
Risk-free interest rate		2.58%
Expected term		10 years
Expected volatility		58.00%

Fair Value Measurements - Stock

Fair Value Measurements - Stock Option Liability Awards (Details) - USD ($) $ in Thousands	Feb. 10, 2015	Dec. 31, 2016	Dec. 31, 2015	Dec. 31, 2014
Stock-Based compensation
Increase in common shares authorized (in shares)	3,000,000
Reclassification from other long-term liabilities to equity		$ 0	$ 288	$ 0
Equity Incentive Plans
Stock-Based compensation
Options granted that were accounted for as liability based awards (in shares)				152,668
Options outstanding that were accounted for as liability based awards (in shares)				149,356
Accrued share-based compensation				$ 500
Change in fair value included in total share based compensation			$ (200)	$ 500
Reclassification from other long-term liabilities to equity	$ 300

Fair Value Measurements - Cha50

Fair Value Measurements - Changes in Stock Option Liability Awards (Details) - Stock Option Liability Awards - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2015	Dec. 31, 2014
Fair Value, Liabilities Measured on Recurring Basis, Unobservable Input Reconciliation, Calculation [Roll Forward]
Balance as of January 1	$ 461	$ 0
Issuance of stock options	0	410
Change in fair value of stock options classified as liability awards	(173)	51
Reclassification of stock options classified as liability awards to equity	(288)	0
Balance as of December 31	$ 0	$ 461

Fair Value Measurements - Fai51

Fair Value Measurements - Fair Value Assumptions of Stock Option Liability Awards (Details) - Stock Option Liability Awards	12 Months Ended
	Dec. 31, 2015	Dec. 31, 2014
Fair Value Measurements, Recurring and Nonrecurring, Valuation Techniques [Line Items]
Dividend yield	0.00%	0.00%
Minimum
Fair Value Measurements, Recurring and Nonrecurring, Valuation Techniques [Line Items]
Risk-free interest rate	1.46%	1.61%
Expected term	4 years 8 months 27 days	4 years 10 months 6 days
Expected volatility	51.00%	56.00%
Maximum
Fair Value Measurements, Recurring and Nonrecurring, Valuation Techniques [Line Items]
Risk-free interest rate	1.67%	2.00%
Expected term	6 years 11 days	6 years 29 days
Expected volatility	53.00%	58.00%

Property, Equipment and Softw52

Property, Equipment and Software, Net (Details) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2016	Dec. 31, 2015	Dec. 31, 2014
Property, Plant and Equipment [Line Items]
Total	$ 42,491	$ 32,031
Less: accumulated depreciation	(22,366)	(12,646)
Property, equipment and software, net	20,125	19,385
Depreciation and amortization expense	9,799	6,074	$ 3,071
Capitalized internal-use software costs
Property, Plant and Equipment [Line Items]
Total	21,993	14,800
Computer hardware and software
Property, Plant and Equipment [Line Items]
Total	18,091	16,028
Furniture and office equipment
Property, Plant and Equipment [Line Items]
Total	440	340
Leasehold improvements
Property, Plant and Equipment [Line Items]
Total	$ 1,967	$ 863

Accrued Expenses and Other Cu53

Accrued Expenses and Other Current Liabilities (Details) - USD ($) $ in Thousands	Dec. 31, 2016	Dec. 31, 2015
Payables and Accruals [Abstract]
Accrued commissions	$ 2,517	$ 2,713
Accrued bonuses	2,037	1,190
Accrued salaries, wages, benefits and related costs	371	1,190
Accrued credit card purchases	597	645
Other accrued expenses and current liabilities	3,878	2,648
Accrued expenses and other current liabilities	$ 9,400	$ 8,386

Debt (Details)

Debt (Details)	Sep. 30, 2016USD ($)	Mar. 08, 2016	Apr. 01, 2015USD ($)	Mar. 30, 2015USD ($)	Jun. 12, 2014USD ($)tranchearrangement	Dec. 31, 2016USD ($)	Dec. 31, 2015USD ($)	Dec. 31, 2014USD ($)	Mar. 07, 2016USD ($)	Feb. 12, 2015USD ($)	Dec. 16, 2014USD ($)
Debt
Number of debt arrangements | arrangement					2
Repayment of debt						$ 46,036,000	$ 27,500,000	$ 31,177,000
Outstanding borrowings under revolving line of credit						27,489,000	31,225,000
Amended Mezzanine Loan and Security Agreement
Debt
Debt instrument maximum borrowing capacity					$ 15,000,000
Number of tranches | tranche					2
Interest rate on outstanding amounts (as a percent)					11.50%
Repayment of debt				$ 15,000,000
Amended Mezzanine Loan and Security Agreement | Amended Term Loan - First Tranche
Debt
Total face amount of debt					$ 10,000,000
Amended Mezzanine Loan and Security Agreement | Amended Term Loan - Second Tranche
Debt
Total face amount of debt											$ 5,000,000
Amended Mezzanine Loan and Security Agreement | Amended Term Loan - 2015 Term Loan
Debt
Total face amount of debt										$ 5,000,000
Repayment of debt			$ 5,000,000
Amended New Loan and Security Agreement
Debt
Maximum borrowing capacity					30,000,000	35,000,000
Increase to borrowing capacity										$ 5,000,000
Percentage of eligible accounts receivable used in calculation of amount available under the borrowing base	85.00%
Percentage of eligible unbilled accounts receivable used in calculation of amount available under the borrowing base	75.00%
Maximum borrowing capacity related to eligible unbilled accounts receivable	$ 12,250,000
Maximum percentage of eligible foreign accounts receivable considered as eligible accounts receivable	25.00%
Available borrowing capacity						$ 5,000,000	3,100,000
Minimum percentage of the Company’s total cash and cash equivalents balance required to be maintained with lender						95.00%
Amended New Loan and Security Agreement | Minimum
Debt
Minimum amount required to be maintained by the company at all times					$ 5,000,000		5,000,000		$ 5,000,000
Amended New Loan and Security Agreement | Revolving Line of Credit
Debt
Effective interest rate						4.25%
Outstanding borrowings under revolving line of credit						$ 27,500,000	$ 31,200,000
Amended New Loan and Security Agreement | Revolving Line of Credit | Minimum
Debt
Debt covenant, required minimum adjusted quick ratio						1
Amended New Loan and Security Agreement | Revolving Line of Credit | Prime
Debt
Potential interest rate margin (as a percent)	0.50%				1.00%
Amended New Loan and Security Agreement | Revolving Line of Credit | Prime | Minimum
Debt
Potential interest rate margin (as a percent)		0.00%
Amended New Loan and Security Agreement | Revolving Line of Credit | Prime | Maximum
Debt
Potential interest rate margin (as a percent)		1.50%

Employee Retirement Savings P55

Employee Retirement Savings Plan (Details) - USD ($)	12 Months Ended
	Dec. 31, 2016	Dec. 31, 2015	Dec. 31, 2014
Compensation and Retirement Disclosure [Abstract]
Plan eligibility, minimum age	21 years
Company contributions to Retirement Plan	$ 0	$ 0	$ 0

Common and Preferred Stock - Na

Common and Preferred Stock - Narrative (Details)	Dec. 31, 2016vote$ / sharesshares	Dec. 31, 2015$ / sharesshares	Mar. 11, 2015$ / sharesshares	Feb. 10, 2015shares
Stockholders' Equity, Number of Shares, Par Value and Other Disclosures [Abstract]
Increase in common shares authorized (in shares)				3,000,000
Common shares authorized	500,000,000	500,000,000	500,000,000	25,000,000
Total shares authorized			510,000,000
Preferred shares authorized			10,000,000
Common shares par value (in usd per share) | $ / shares	$ 0.00005	$ 0.00005	$ 0.00005
Preferred stock par value (in usd per share) | $ / shares			$ 0.00005
Number of votes per common stock share | vote	1

Common and Preferred Stock - Co

Common and Preferred Stock - Common Stock Reserved for Issuance (Details) - shares	Dec. 31, 2016	Dec. 31, 2015	Mar. 11, 2015	Feb. 10, 2015	Jan. 31, 2015
Common Stock Reserved for Issuance
Total shares reserved	1,868,680	1,565,251
Common shares authorized	500,000,000	500,000,000	500,000,000	25,000,000
2015 Employee Stock Purchase Plan
Common Stock Reserved for Issuance
Total shares reserved	66,823	60,318			93,750
Equity Incentive Plans
Common Stock Reserved for Issuance
Total shares reserved	189,513	380,460
Stock options
Common Stock Reserved for Issuance
Total shares reserved	1,026,244	1,074,473
Unvested restricted stock units
Common Stock Reserved for Issuance
Total shares reserved	536,100	0
Lender warrants to purchase common stock
Common Stock Reserved for Issuance
Total shares reserved	50,000	50,000

Convertible Preferred Stock (De

Convertible Preferred Stock (Details) - USD ($) $ / shares in Units, $ in Thousands	12 Months Ended
	Dec. 31, 2015	Mar. 11, 2015
Convertible Preferred Stock
Number of Shares Authorized		3,737,906
Number of Shares Outstanding		3,712,206
Increase (Decrease) in Temporary Equity [Roll Forward]
Balance of convertible preferred stock	$ 25,476
Balance, beginning of period	25,476
Conversion to common stock upon IPO	(25,476)
Balance, end of period	0
Series A convertible preferred stock
Convertible Preferred Stock
Number of Shares Authorized		621,626
Number of Shares Outstanding		595,936
Original Issue and Conversion Price per Share (in usd per share)		$ 2.328
Increase (Decrease) in Temporary Equity [Roll Forward]
Balance of convertible preferred stock	1,387
Balance, beginning of period	1,387
Conversion to common stock upon IPO	(1,387)
Balance, end of period	0
Series B convertible preferred stock
Convertible Preferred Stock
Number of Shares Authorized		912,342
Number of Shares Outstanding		912,342
Original Issue and Conversion Price per Share (in usd per share)		$ 3.38624
Increase (Decrease) in Temporary Equity [Roll Forward]
Balance of convertible preferred stock	3,089
Balance, beginning of period	3,089
Conversion to common stock upon IPO	(3,089)
Balance, end of period	0
Series C convertible preferred stock
Convertible Preferred Stock
Number of Shares Authorized		1,351,626
Number of Shares Outstanding		1,351,626
Original Issue and Conversion Price per Share (in usd per share)		$ 5.9192
Increase (Decrease) in Temporary Equity [Roll Forward]
Balance of convertible preferred stock	8,000
Balance, beginning of period	8,000
Conversion to common stock upon IPO	(8,000)
Balance, end of period	0
Series D convertible preferred stock
Convertible Preferred Stock
Number of Shares Authorized		852,312
Number of Shares Outstanding		852,302
Original Issue and Conversion Price per Share (in usd per share)		$ 15.2528
Increase (Decrease) in Temporary Equity [Roll Forward]
Balance of convertible preferred stock	13,000
Balance, beginning of period	13,000
Conversion to common stock upon IPO	(13,000)
Balance, end of period	$ 0
IPO
Convertible Preferred Stock
Shares issued upon conversion		3,712,206

Stock-Based Compensation - Equi

Stock-Based Compensation - Equity Incentive Plan Terms (Details) - shares	1 Months Ended	12 Months Ended
	Jan. 31, 2015	Dec. 31, 2016
Equity Incentive Plans
Stock-Based compensation
Shares available for future grants		189,513
Equity Incentive Plans | Stock options
Award terms
Term of grant (in years)		10 years
Equity Incentive Plans | Stock options | Initial Cliff Period
Award terms
Vesting period		1 year
Equity Incentive Plans | Stock options | Remaining Vesting Period
Award terms
Vesting period		36 months
2015 Equity Incentive Plan
Stock-Based compensation
Initial shares available for grant from equity incentive plan	625,000
Plan terms
Number of shares option, minimum annual increase in number of shares reserved for issuance	437,500
Percentage of common stock outstanding option, minimum annual increase in number of shares reserved for issuance (as a percent)	5.00%
Plan term (in years)	10 years
2015 Equity Incentive Plan | Restricted stock units
Award terms
Vesting period		2 years
2015 Equity Incentive Plan | Restricted stock units | Initial Cliff Period
Award terms
Vesting period		6 months
2010 Equity Incentive Plan
Stock-Based compensation
Maximum shares available for grant transferred between equity incentive plans.	1,134,467

Stock-Based Compensation - Allo

Stock-Based Compensation - Allocation of Stock-Based Compensation Expense, Stock Options (Details) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2016	Dec. 31, 2015	Dec. 31, 2014
Equity Incentive Plans
Share-based compensation expense by statement of operations line item
Change in fair value included in total share based compensation		$ (200)	$ 500
Stock options
Share-based compensation expense by statement of operations line item
Stock-based compensation expense	$ 3,601	3,353	2,339
Stock options | Other cost of revenue
Share-based compensation expense by statement of operations line item
Stock-based compensation expense	75	75	20
Stock options | Sales and marketing
Share-based compensation expense by statement of operations line item
Stock-based compensation expense	719	720	505
Stock options | Research and development
Share-based compensation expense by statement of operations line item
Stock-based compensation expense	1,268	1,114	756
Stock options | General and administrative
Share-based compensation expense by statement of operations line item
Stock-based compensation expense	$ 1,539	$ 1,444	$ 1,058

Stock-Based Compensation - Fair

Stock-Based Compensation - Fair Value Assumptions, Stock Options (Details) - Stock options	12 Months Ended
	Dec. 31, 2016	Dec. 31, 2015	Dec. 31, 2014
Stock-Based compensation
Risk free interest rate, minimum	1.16%	1.57%	1.32%
Risk free interest rate, maximum	2.10%	1.94%	2.04%
Expected term (years)	6 years 29 days
Expected volatility, minimum	46.00%	46.00%	56.00%
Expected volatility, maximum	47.00%	59.00%	60.00%
Dividend yield	0.00%	0.00%	0.00%
Minimum
Stock-Based compensation
Expected term (years)		6 years 11 days	4 years
Maximum
Stock-Based compensation
Expected term (years)		6 years 29 days	6 years 29 days

Stock-Based Compensation - Addi

Stock-Based Compensation - Additional Disclosures (Details) - USD ($) $ / shares in Units, $ in Millions	12 Months Ended
	Dec. 31, 2016	Dec. 31, 2015	Dec. 31, 2014
Stock-Based compensation
Weighted-average grant date fair value (in usd per share)	$ 3.87	$ 11.20	$ 28.24
Unrecognized compensation cost related to nonvested share-based compensation arrangements	$ 5.7
Intrinsic value of options exercised	$ 0.2	$ 3.9	$ 5.4
Stock options
Stock-Based compensation
Expected weighted-average period for recognition of unrecognized stock-based compensation costs (in years)	1 year 11 days

Stock-Based Compensation - Stoc

Stock-Based Compensation - Stock Option Activity (Details) - USD ($) $ / shares in Units, $ in Thousands	12 Months Ended
	Dec. 31, 2016	Dec. 31, 2015
Number of Options
Outstanding balance at beginning of period (in shares)	1,074,473
Granted (in shares)	133,760
Exercised (in shares)	(31,125)
Cancelled (in shares)	(150,864)
Outstanding balance at end of period (in shares)	1,026,244	1,074,473
Exercisable at end of period (in shares)	565,043
Vested and expected to vest at end of period (in shares)	986,301
Weighted- Average Exercise Price
Outstanding balance at beginning of period (in usd per share)	$ 30.69
Granted (in usd per share)	8.44
Exercised (in usd per share)	3.65
Cancelled (in usd per share)	29.84
Outstanding balance at end of period (in usd per share)	28.73	$ 30.69
Exercisable at end of period (in usd per share)	30.65
Vested and expected to vest at end of period (in usd per share)	$ 29.17
Weighted- Average Remaining Contractual Term
Outstanding balance at end of period (in years)	7 years 7 months 24 days	8 years 4 months 21 days
Exercisable at end of period (in years)	6 years 10 months 28 days
Vested and expected to vest at end of period (in years)	7 years 7 months 6 days
Aggregate Intrinsic Value
Outstanding balance at end of period	$ 299	$ 500
Exercisable at end of period	299
Vested and expected to vest at end of period	$ 299

Stock-Based Compensation - St64

Stock-Based Compensation - Stock Options Outstanding and Vested by Exercise Price Range (Details)	12 Months Ended
	Dec. 31, 2016$ / sharesshares
Options Outstanding
Number of Options (in shares) | shares	1,026,244
Weighted Average Exercise Price (in usd per share)	$ 28.73
Weighted- Average Remaining Contractual Term (in Years)	7 years 7 months 24 days
Options Exercisable
Number of Options (in shares) | shares	565,043
Weighted Average Exercise Price (in usd per share)	$ 30.65
Weighted- Average Remaining Contractual Term (in Years)	6 years 10 months 28 days
$1.36 - $15.00
Share-based Compensation, Shares Authorized under Stock Option Plans, Exercise Price Range [Line Items]
Exercise price range, minimum	$ 1.36
Exercise price range, maximum	$ 15
Options Outstanding
Number of Options (in shares) | shares	313,087
Weighted Average Exercise Price (in usd per share)	$ 7.11
Weighted- Average Remaining Contractual Term (in Years)	6 years 11 months 19 days
Options Exercisable
Number of Options (in shares) | shares	175,117
Weighted Average Exercise Price (in usd per share)	$ 6.10
Weighted- Average Remaining Contractual Term (in Years)	5 years 1 month 6 days
$15.01 - $30.00
Share-based Compensation, Shares Authorized under Stock Option Plans, Exercise Price Range [Line Items]
Exercise price range, minimum	$ 15.01
Exercise price range, maximum	$ 30
Options Outstanding
Number of Options (in shares) | shares	287,808
Weighted Average Exercise Price (in usd per share)	$ 20.26
Weighted- Average Remaining Contractual Term (in Years)	8 years 6 months 7 days
Options Exercisable
Number of Options (in shares) | shares	111,696
Weighted Average Exercise Price (in usd per share)	$ 20.35
Weighted- Average Remaining Contractual Term (in Years)	8 years 3 months 22 days
$30.01 - $45.00
Share-based Compensation, Shares Authorized under Stock Option Plans, Exercise Price Range [Line Items]
Exercise price range, minimum	$ 30.01
Exercise price range, maximum	$ 45
Options Outstanding
Number of Options (in shares) | shares	59,336
Weighted Average Exercise Price (in usd per share)	$ 36.48
Weighted- Average Remaining Contractual Term (in Years)	8 years 7 days
Options Exercisable
Number of Options (in shares) | shares	30,116
Weighted Average Exercise Price (in usd per share)	$ 36.61
Weighted- Average Remaining Contractual Term (in Years)	7 years 9 months
$45.01 - $60.72
Share-based Compensation, Shares Authorized under Stock Option Plans, Exercise Price Range [Line Items]
Exercise price range, minimum	$ 45.01
Exercise price range, maximum	$ 60.72
Options Outstanding
Number of Options (in shares) | shares	366,013
Weighted Average Exercise Price (in usd per share)	$ 52.63
Weighted- Average Remaining Contractual Term (in Years)	7 years 5 months 27 days
Options Exercisable
Number of Options (in shares) | shares	248,114
Weighted Average Exercise Price (in usd per share)	$ 51.89
Weighted- Average Remaining Contractual Term (in Years)	7 years 5 months 16 days

Stock-Based Compensation - Al65

Stock-Based Compensation - Allocation of Stock-Based Compensation Expense, RSUs (Details) - Restricted stock units $ in Thousands	12 Months Ended
	Dec. 31, 2016USD ($)
Share-based compensation expense by statement of operations line item
Stock-based compensation expense	$ 588
Unrecognized compensation cost related to nonvested share-based compensation arrangements	$ 4,200
Expected weighted-average period for recognition of unrecognized stock-based compensation costs (in years)	11 months 19 days
Other cost of revenue
Share-based compensation expense by statement of operations line item
Stock-based compensation expense	$ 27
Sales and marketing
Share-based compensation expense by statement of operations line item
Stock-based compensation expense	104
Research and development
Share-based compensation expense by statement of operations line item
Stock-based compensation expense	294
General and administrative
Share-based compensation expense by statement of operations line item
Stock-based compensation expense	$ 163

Stock-Based Compensation - Rest

Stock-Based Compensation - Restricted Stock Unit Activity (Details) - Restricted stock units	12 Months Ended
	Dec. 31, 2016$ / sharesshares
Number of Shares
Nonvested balance at beginning of period (in shares) | shares	0
Granted (in shares) | shares	566,420
Vested (in shares) | shares	0
Forfeited (in shares) | shares	(30,320)
Nonvested balance at end of period (in shares) | shares	536,100
Weighted- Average Grant Date Fair Value
Nonvested balance at beginning of period (in usd per share) | $ / shares	$ 0
Granted (in usd per share) | $ / shares	8.87
Vested (in usd per share) | $ / shares	0
Forfeited (in usd per share) | $ / shares	8.87
Nonvested balance at end of period (in usd per share) | $ / shares	$ 8.87

Stock-Based Compensation - Empl

Stock-Based Compensation - Employee Stock Purchase Plan (Details)	1 Months Ended	6 Months Ended			8 Months Ended	12 Months Ended
	Jan. 31, 2015USD ($)offering_periodshares	Apr. 30, 2017$ / shares	Oct. 31, 2016$ / shares	Apr. 30, 2016$ / shares	Oct. 30, 2015$ / shares	Dec. 31, 2016USD ($)shares	Dec. 31, 2015USD ($)shares
Stock-Based compensation
Total shares reserved						1,868,680	1,565,251
Intrinsic value of shares of stock purchased under ESPP | $						$ 100,000	$ 100,000
2015 Employee Stock Purchase Plan
Stock-Based compensation
Maximum percentage of eligible compensation per employee to purchase shares of common stock	15.00%
Maximum number of shares per offering period per employee	375
Maximum share value per calendar year per employee | $	$ 25,000
Employee purchase price, percentage of fair market value of common stock	85.00%
Number of offering periods under terms of plan | offering_period	2
Offering periods beginning on May 1 and November 1	6 months
Issuance of common stock under employee stock purchase plan (in shares)						55,995
Accumulated employee withholdings | $						$ 200,000
Number of employment hours requirement per week during requisite service period	20 hours
Offering period, maximum	27 months
Total shares reserved	93,750					66,823	60,318
Number of shares option, minimum annual increase in number of shares reserved for issuance	62,500
Percentage of common stock outstanding option, minimum annual increase in number of shares reserved for issuance (as a percent)	1.00%
Discount on purchase of stock (as a percent)						15.00%
Grant date fair value per share (in usd per share) | $ / shares			$ 2.23	$ 5.98	$ 15.38
Unrecognized compensation cost related to nonvested share-based compensation arrangements | $						$ 100,000
Expected weighted-average period for recognition of unrecognized stock-based compensation costs (in years)						3 months 18 days
2015 Employee Stock Purchase Plan | Forecast
Stock-Based compensation
Grant date fair value per share (in usd per share) | $ / shares		$ 2.35
2015 Employee Stock Purchase Plan | Call Option
Stock-Based compensation
Fair value of option (as a percent)						85.00%
2015 Employee Stock Purchase Plan | Put Option
Stock-Based compensation
Fair value of option (as a percent)						15.00%
2015 Employee Stock Purchase Plan | Minimum
Stock-Based compensation
Requisite service period for award eligibility per year	5 months

Stock-Based Compensation - Al68

Stock-Based Compensation - Allocation of Stock-Based Compensation Expense, ESPP (Details) - 2015 Employee Stock Purchase Plan - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2016	Dec. 31, 2015
ESPP stock-based compensation expense by statement of operations line item
Stock-based compensation expense	$ 220	$ 504
Other cost of revenue
ESPP stock-based compensation expense by statement of operations line item
Stock-based compensation expense	4	17
Sales and marketing
ESPP stock-based compensation expense by statement of operations line item
Stock-based compensation expense	64	177
Research and development
ESPP stock-based compensation expense by statement of operations line item
Stock-based compensation expense	125	244
General and administrative
ESPP stock-based compensation expense by statement of operations line item
Stock-based compensation expense	$ 27	$ 66

Stock-Based Compensation - Fa69

Stock-Based Compensation - Fair Value Assumptions, ESPP (Details) - 2015 Employee Stock Purchase Plan	12 Months Ended
	Dec. 31, 2016	Dec. 31, 2015
Stock-Based compensation
Risk free interest rate, minimum	0.41%	0.10%
Risk free interest rate, maximum	0.50%	0.27%
Expected term (years)	6 months
Expected volatility, minimum	41.00%	55.00%
Expected volatility, maximum	43.00%	61.00%
Dividend yield	0.00%	0.00%
Minimum
Stock-Based compensation
Expected term (years)		6 months
Maximum
Stock-Based compensation
Expected term (years)		7 months 2 days

Income Taxes - Schedule of Loss

Income Taxes - Schedule of Loss Before Income Taxes (Details) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2016	Dec. 31, 2015	Dec. 31, 2014
Income Tax Disclosure [Abstract]
Domestic	$ (15,086)	$ (19,917)	$ (11,222)
International	(2,765)	(2,536)	(1,767)
Loss before income taxes	$ (17,851)	$ (22,453)	$ (12,989)

Income Taxes - Effective Tax Ra

Income Taxes - Effective Tax Rate Reconciliation (Details) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2016	Dec. 31, 2015	Dec. 31, 2014
Income Tax Disclosure [Abstract]
Federal statutory income tax rate (as a percent)	34.00%	34.00%	34.00%
Effective Income Tax Rate Reconciliation, Amount [Abstract]
Effective tax rate (as a percent)	0.00%	0.00%	0.00%
Statutory rate of 34%	$ (6,069)	$ (7,634)	$ (4,416)
State taxes, net of federal benefit	(388)	(615)	(256)
Foreign rate differential	455	346	245
Stock-based compensation permanent differences	785	836	464
Meals and entertainment permanent differences	376	385	232
Miscellaneous permanent differences	264	165	32
Warrant fair market value adjustment	0	(59)	229
Other adjustments	(96)	(3)	474
Change in valuation allowance	4,673	6,579	2,996
Provision for income taxes	$ 0	$ 0	$ 0

Income Taxes - Components of De

Income Taxes - Components of Deferred Tax Assets and Liabilities (Details) - USD ($) $ in Thousands	Dec. 31, 2016	Dec. 31, 2015
Deferred Tax Assets
Accrued expenses	$ 1,303	$ 882
Stock-based compensation	1,611	854
Future benefit of carry forward losses	21,742	17,946
Other accruals	678	488
Valuation allowance	(19,544)	(14,871)
Total deferred tax asset	5,790	5,299
Deferred Tax Liabilities
Amortization	(4,482)	(3,688)
Depreciation	(1,308)	(1,591)
Other accruals	0	(20)
Total deferred tax liability	5,790	5,299
Net deferred tax assets (liabilities)	$ 0	$ 0

Income Taxes - Additional Discl

Income Taxes - Additional Disclosures (Details)	Dec. 31, 2016USD ($)
Operating loss carryforwards
Undistributed earnings of non-U.S. subsidiary	$ 0
Federal
Operating loss carryforwards
Operating loss carry forwards	57,200,000
State
Operating loss carryforwards
Operating loss carry forwards	48,800,000
Foreign
Operating loss carryforwards
Operating loss carry forwards	$ 7,100,000

Commitments and Contingencies -

Commitments and Contingencies - Future Minimum Lease Payments (Details) $ in Thousands	Dec. 31, 2016USD ($)
Year Ending December 31,
2,017	$ 2,946
2,018	2,784
2,019	2,160
2,020	1,510
2,021	1,254
Thereafter	1,772
Total minimum lease payments	$ 12,426

Commitments and Contingencies75

Commitments and Contingencies - Narrative (Details) - USD ($) $ in Millions	12 Months Ended
	Dec. 31, 2016	Dec. 31, 2015	Dec. 31, 2014
Commitments and Contingencies Disclosure [Abstract]
Deferred rent	$ 1.4	$ 1
Outstanding letters of credit	0.5
Rent expense	2.9	$ 2.1	$ 1.6
Total contractual commitments	4.9
Commitments due within next year	3.6
Commitments due within one to two years	$ 1.3

Earnings Per Share (Details)

Earnings Per Share (Details) - shares	12 Months Ended
	Dec. 31, 2016	Dec. 31, 2015	Dec. 31, 2014
Antidilutive Securities Excluded from Computation of Earnings Per Share [Line Items]
Anti-dilutive securities excluded from the calculation of weighted average common shares outstanding	1,649,327	1,172,693	4,607,235
Convertible Series A preferred stock
Antidilutive Securities Excluded from Computation of Earnings Per Share [Line Items]
Anti-dilutive securities excluded from the calculation of weighted average common shares outstanding	0	0	595,936
Convertible Series B preferred stock
Antidilutive Securities Excluded from Computation of Earnings Per Share [Line Items]
Anti-dilutive securities excluded from the calculation of weighted average common shares outstanding	0	0	912,342
Convertible Series C preferred stock
Antidilutive Securities Excluded from Computation of Earnings Per Share [Line Items]
Anti-dilutive securities excluded from the calculation of weighted average common shares outstanding	0	0	1,351,626
Convertible Series D preferred stock
Antidilutive Securities Excluded from Computation of Earnings Per Share [Line Items]
Anti-dilutive securities excluded from the calculation of weighted average common shares outstanding	0	0	852,302
Common stock subject to repurchase
Antidilutive Securities Excluded from Computation of Earnings Per Share [Line Items]
Anti-dilutive securities excluded from the calculation of weighted average common shares outstanding	0	0	1,250
Lender warrants to purchase common stock
Antidilutive Securities Excluded from Computation of Earnings Per Share [Line Items]
Anti-dilutive securities excluded from the calculation of weighted average common shares outstanding	50,000	50,000	37,500
2015 ESPP
Antidilutive Securities Excluded from Computation of Earnings Per Share [Line Items]
Anti-dilutive securities excluded from the calculation of weighted average common shares outstanding	36,983	48,220	0
Restricted stock units
Antidilutive Securities Excluded from Computation of Earnings Per Share [Line Items]
Anti-dilutive securities excluded from the calculation of weighted average common shares outstanding	536,100	0	0
Stock options
Antidilutive Securities Excluded from Computation of Earnings Per Share [Line Items]
Anti-dilutive securities excluded from the calculation of weighted average common shares outstanding	1,026,244	1,074,473	856,279

Segment and Geographic Inform77

Segment and Geographic Information (Details) - segment	12 Months Ended
	Dec. 31, 2016	Dec. 31, 2015	Dec. 31, 2014
Segment Reporting [Abstract]
Number of operating segments	1
Number of reportable segments	1
Long-lived Assets | United States
Revenues from External Customers and Long-Lived Assets [Line Items]
Concentration risk, percentage	97.00%	98.00%	96.00%
Revenue | United States
Revenues from External Customers and Long-Lived Assets [Line Items]
Concentration risk, percentage	99.00%	99.00%	99.00%

Related Party (Details)

Related Party (Details) - Kevin Dulsky - USD ($)	Aug. 15, 2015	Dec. 31, 2015
Related party transactions
Termination of agreement, notice period	15 days
Accounts payable related to advisor agreement		$ 0
General and administrative
Related party transactions
Expense incurred related to advisor agreement		$ 20,000