ThredUp (TDUP) 10-Q 13 May 21 2021 Q1 Quarterly report Financial data

Cover Page

Cover Page - shares	3 Months Ended
	Mar. 31, 2021	Apr. 30, 2021
Document Information [Line Items]
Document Type	10-Q
Document Quarterly Report	true
Document Period End Date	Mar. 31, 2021
Document Transition Report	false
Entity File Number	001-40249
Entity Registrant Name	ThredUp Inc.
Entity Incorporation, State or Country Code	DE
Entity Tax Identification Number	26-4009181
Entity Address, Address Line One	969 Broadway
Entity Address, Address Line Two	Suite 200
Entity Address, City or Town	Oakland
Entity Address, State or Province	CA
Entity Address, Postal Zip Code	94607
City Area Code	415
Local Phone Number	402-5202
Title of each class	Class A common stock, $0.0001 par value per share
Trading Symbol(s)	TDUP
Name of each exchange on which registered	NASDAQ
Entity Current Reporting Status	No
Entity Interactive Data Current	Yes
Entity Filer Category	Non-accelerated Filer
Entity Small Business	false
Entity Emerging Growth Company	true
Entity Ex Transition Period	false
Entity Shell Company	false
Amendment Flag	false
Document Fiscal Year Focus	2021
Document Fiscal Period Focus	Q1
Entity Central Index Key	0001484778
Current Fiscal Year End Date	--12-31
Common stock Class A
Document Information [Line Items]
Entity Common Stock, Shares Outstanding		15,022,873
Common stock Class B
Document Information [Line Items]
Entity Common Stock, Shares Outstanding		79,183,025

Condensed Consolidated Balance

Condensed Consolidated Balance Sheets - USD ($) $ in Thousands	Mar. 31, 2021	Dec. 31, 2020
Current assets
Cash and cash equivalents	$ 246,514	$ 64,485
Accounts receivable, net	1,726	1,823
Inventory, net	3,482	3,519
Other current assets	3,168	5,332
Total current assets	254,890	75,159
Operating lease right-of-use assets	22,338	23,656
Property and equipment, net	43,562	41,131
Other assets	2,980	2,965
Total assets	323,770	142,911
Current liabilities
Accounts payable	14,540	9,386
Accrued and other current liabilities	37,720	32,541
Seller payable	15,194	13,724
Operating lease liabilities, current	3,095	3,643
Current portion of long-term debt	5,736	3,270
Total current liabilities	76,285	62,564
Operating lease liabilities, non-current	20,811	21,574
Long-term debt	33,320	31,190
Other non-current liabilities	1,927	2,719
Total liabilities	132,343	118,047
Commitments and contingencies (Note 10)
Convertible preferred stock: $0.0001 par value; 100,000,000 and 68,139,958 shares authorized as of March 31, 2021 and December 31, 2020, respectively; 0 and 65,970,938 shares issued and outstanding as of March 31, 2021 and December 31, 2020, respectively	0	247,041
Stockholders’ equity:
Class A and B common stock, $0.0001 par value; 1,120,000,000 and 110,000,000 shares authorized as of March 31, 2021 and December 31, 2020, respectively; 94,143,694 and 12,889,760 shares issued and outstanding as of March 31, 2021 and December 31, 2020, respectively	9	1
Additional paid-in capital	459,756	29,989
Accumulated deficit	(268,338)	(252,167)
Total stockholders’ equity (deficit)	191,427	(222,177)
Total liabilities, convertible preferred stock and stockholders’ equity	$ 323,770	$ 142,911

Condensed Consolidated Balanc_2

Condensed Consolidated Balance Sheets (Parenthetical) - $ / shares	Mar. 31, 2021	Dec. 31, 2020
Liabilities, Convertible Preferred Stock and Stockholders’ Equity
Convertible preferred stock (in dollars per share)	$ 0.0001	$ 0.0001
Convertible preferred stock, shares authorized (in shares)	100,000,000	68,139,958
Convertible preferred stock, shares outstanding (in shares)	0	65,970,938
Convertible preferred stock, shares issued (in shares)	0	65,970,938
Stockholders’ equity:
Common stock, par value (in dollars per share)	$ 0.0001	$ 0.0001
Common stock, shares authorized (in shares)	1,120,000,000	110,000,000
Common stock, shares issued (in shares)	94,143,694	12,889,760
Common stock, shares outstanding (in shares)	94,143,694	12,889,760

Condensed Consolidated Statemen

Condensed Consolidated Statements of Operations and Comprehensive Loss - USD ($) $ in Thousands	3 Months Ended
	Mar. 31, 2021	Mar. 31, 2020
Revenue:
Total revenue	$ 55,680	$ 48,315
Cost of revenue:
Total cost of revenue	15,962	15,689
Gross profit	39,718	32,626
Operating expenses:
Operations, product and technology	28,312	25,475
Marketing	15,446	13,001
Sales, general and administrative	10,638	7,433
Total operating expenses	54,396	45,909
Operating loss	(14,678)	(13,283)
Interest and other (expense) income, net	(1,466)	68
Loss before provision for income taxes	(16,144)	(13,215)
Provision for income taxes	27	0
Net loss	(16,171)	(13,215)
Total comprehensive loss	$ (16,171)	$ (13,215)
Net loss per share attributable to common stockholders, basic (in dollars per share)	$ (0.86)	$ (1.23)
Net loss per share attributable to common stockholders, diluted (in dollars per share)	$ (0.86)	$ (1.23)
Weighted-average shares used in computing net loss per share attributable to common stockholders, basic (in shares)	18,701,108	10,763,234
Weighted-average shares used in computing net loss per share attributable to common stockholders, diluted (in shares)	18,701,108	10,763,234
Consignment
Revenue:
Total revenue	$ 44,688	$ 35,314
Cost of revenue:
Total cost of revenue	10,832	8,816
Product
Revenue:
Total revenue	10,992	13,001
Cost of revenue:
Total cost of revenue	$ 5,130	$ 6,873

Condensed Consolidated Statem_2

Condensed Consolidated Statements of Convertible Preferred Stock and Stockholders’ Equity - USD ($) $ in Thousands	Total	ASC 842 adoption (eff. January 1, 2020)	Common Stock	Additional Paid-in Capital	Accumulated Deficit	Accumulated DeficitASC 842 adoption (eff. January 1, 2020)
Beginning balance (in shares) at Dec. 31, 2019	65,928,261
Beginning balance at Dec. 31, 2019	$ 246,905
Ending balance (in shares) at Mar. 31, 2020	65,928,261
Ending balance at Mar. 31, 2020	$ 246,905
Beginning balance (in shares) at Dec. 31, 2019			10,647,380
Beginning balance at Dec. 31, 2019	(183,241)	$ (565)	$ 1	$ 20,483	$ (203,725)	$ (565)
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Exercise of stock options (in shares)			118,685
Exercise of stock options	10		$ 0	10
Stock-based compensation	1,442			1,442
Net loss	(13,215)				(13,215)
Ending balance (in shares) at Mar. 31, 2020			10,766,065
Ending balance at Mar. 31, 2020	$ (195,569)		$ 1	21,935	(217,505)
Beginning balance (in shares) at Dec. 31, 2020	65,970,938
Beginning balance at Dec. 31, 2020	$ 247,041
Convertible Preferred Stock
Preferred stock conversion to Class B common stock (in shares)	(65,970,938)
Preferred stock conversion to Class B common stock	$ (247,041)
Ending balance (in shares) at Mar. 31, 2021	0
Ending balance at Mar. 31, 2021	$ 0
Beginning balance (in shares) at Dec. 31, 2020	12,889,760		12,889,760
Beginning balance at Dec. 31, 2020	$ (222,177)		$ 1	29,989	(252,167)
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Preferred stock conversion to Class B common stock	247,041		$ 7	247,034
Sale of Class A common stock upon initial public offering, net of issuance (in shares)			13,800,000
Sale of Class A common stock upon initial public offering, net of issuance costs	175,534		$ 1	175,533
Conversion of convertible preferred stock warrants to Class B common stock warrants	1,827			1,827
Cashless exercise of common stock warrant to Class B common stock (in shares)			24,837
Exercise of stock options (in shares)			1,458,159
Exercise of stock options	1,875		$ 0	1,875
Stock-based compensation	3,498			3,498
Net loss	$ (16,171)				(16,171)
Ending balance (in shares) at Mar. 31, 2021	94,143,694		94,143,694
Ending balance at Mar. 31, 2021	$ 191,427		$ 9	$ 459,756	$ (268,338)

Condensed Consolidated Statem_3

Condensed Consolidated Statements of Cash Flows - USD ($) $ in Thousands	3 Months Ended
	Mar. 31, 2021	Mar. 31, 2020
Cash flows from operating activities
Net loss	$ (16,171)	$ (13,215)
Adjustments to reconcile net loss to net cash provided by (used in) operating activities:
Depreciation and amortization	2,038	1,245
Stock-based compensation expense	3,498	1,442
Reduction in the carrying amount of right-of-use assets	1,318	873
Changes in fair value of convertible preferred stock warrants and others	1,048	(126)
Changes in operating assets and liabilities:
Accounts receivable, net	97	(338)
Inventory, net	37	51
Other current and non-current assets	(457)	(1,977)
Accounts payable	4,722	1,122
Accrued and other current liabilities	4,784	1,791
Seller payable	1,470	1,218
Operating lease liabilities	(1,311)	(1,186)
Other non-current liabilities	4	(2)
Net cash provided by (used in) operating activities	1,077	(9,102)
Cash flows from investing activities
Purchase of property and equipment	(4,099)	(4,673)
Net cash used in investing activities	(4,099)	(4,673)
Cash flows from financing activities
Proceeds from debt issuance, net of issuance costs	4,625	0
Repayment of debt	0	(714)
Proceeds from issuance of Class A common stock upon initial public offering, net of underwriting discounts and commissions	180,284	0
Proceeds from exercise of common stock options	1,875	10
Payment of costs for the initial public offering	(1,733)	(81)
Net cash provided by (used in) financing activities	185,051	(785)
Net increase (decrease) in cash, cash equivalents and restricted cash and cash equivalents	182,029	(14,560)
Cash, cash equivalents and restricted cash and cash equivalents
Beginning of period	67,539	87,853
End of period	$ 249,568	$ 73,293

Organization and Description of

Organization and Description of Business	3 Months Ended
	Mar. 31, 2021
Organization, Consolidation and Presentation of Financial Statements [Abstract]
Organization and Description of Business	Organization and Description of Business ThredUp Inc. (“ThredUp” or “Company”) was formed as a corporation in the State of Delaware in January 2009. ThredUp is a large resale platform that enables consumers to buy and sell secondhand women’s and kid’s apparel, shoes and accessories. The Company conducts its marketing and administrative functions from Oakland, California and Scottsdale, Arizona and operates its fulfillment centers in Pennsylvania, Illinois, Georgia, and Arizona. Initial Public Offering The Company’s registration statement on Form S-1 related to its initial public offering (“IPO”) was declared effective on March 25, 2021 by the Securities and Exchange Commission (“SEC”), and the Company’s Class A common stock began trading on the Nasdaq Global Select Market on March 26, 2021. Upon the closing of the IPO, the Company sold 13,800,000 shares of Class A common stock (which included 1,800,000 shares that were offered and sold pursuant to the full exercise of the underwriters’ option to purchase additional shares) to the public at a price of $14.00 per share. The aggregate net proceeds were $175.5 million after deducting offering costs, underwriting discounts and commissions of $17.7 million. Immediately prior to the completion of the IPO, the Company filed its Amended and Restated Certificate of Incorporation, which authorized a total of 1,000,000,000 shares of Class A common stock, 120,000,000 shares of Class B common stock and 100,000,000 shares of undesignated preferred stock. Immediately prior to the completion of the IPO, 65,970,938 shares of the convertible preferred stock then outstanding were converted into an equivalent number of shares of Class B common stock. The Company reclassified the convertible preferred stock to Class B common stock and additional paid-in capital upon the conversion in the three months ended March 31, 2021. 12,889,760 shares of the outstanding historical common stock were reclassified into an equivalent number of shares of Class B common stock. 164,973

Significant Accounting Policies

Significant Accounting Policies	3 Months Ended
	Mar. 31, 2021
Accounting Policies [Abstract]
Significant Accounting Policies	Significant Accounting Policies Basis of Presentation and Use of Estimates The accompanying condensed consolidated financial statements include the accounts of the Company and its wholly-owned subsidiaries. All intercompany account balances and transactions have been eliminated upon consolidation. The unaudited condensed consolidated financial statements were prepared in accordance with generally accepted accounting principles (“GAAP”) in the United States for interim financial information and with the instructions to Form 10‑Q and Article 10 of Regulation S-X. As permitted under those rules, certain footnotes or other financial information can be condensed or omitted. The preparation of consolidated financial statements in conformity with GAAP requires management to make estimates and assumptions that affect the amounts that are reported in the consolidated financial statements and the related disclosures. Actual results could differ from those estimates. Significant items subject to such estimates and assumptions include, but are not limited to, the useful lives of property and equipment, allowance for sales returns, allowance for bad debts, breakage on loyalty points and rewards, valuation of inventory, warrants, stock-based compensation, valuation of right-of-use assets and income taxes. In the opinion of management, the accompanying unaudited condensed consolidated financial statements reflect all normal and recurring adjustments necessary to present fairly the financial position of the Company as of March 31, 2021, and the results of operations and cash flows for the interim periods presented. The accompanying condensed consolidated financial statements and related financial information should b e read in conjunction with the Company’s audited consolidated financial statements and related notes for the year ended December 31, 2020 included in the final prospectus for the IPO dated March 25, 2021. Concentrations of Credit Risks As of March 31, 2021 and December 31, 2020 , there were no customers that represented 10% or more of the Company’s accounts receivable balance. There were no customers that individually exceeded 10% of the Company’s revenue for the three months ended March 31, 2021 and 2020, respectively. Revenue Recognition Revenue from Loyalty Reward Redemption or Expiration For the three months ended March 31, 2021 and 2020, the Company recognized $3.3 million and $0.2 million, respectively, of revenue from loyalty reward redemption or expiration. Cash, Cash Equivalents and Restricted Cash and Cash Equivalents The following table provides a reconciliation of cash, cash equivalents and restricted cash and cash equivalents reported within the condensed consolidated balance sheets to the amounts shown in the condensed consolidated statements of cash flows (in thousands): March 31, December 31, 2021 2020 Cash and cash equivalents $ 246,514 $ 64,485 Restricted cash and cash equivalents, current and non-current 3,054 3,054 Total cash, cash equivalents and restricted cash and cash equivalents $ 249,568 $ 67,539 Restricted cash and cash equivalents, non-current of $2.7 million is included in the other assets in the condensed consolidated balance sheets statements as of March 31, 2021 and December 31, 2020 . Net Loss Per Share Attributable to Common Stockholders The Company follows the two-class method when computing net loss per common share when shares issued meet the definition of participating securities. The rights, including the liquidation and dividend rights and sharing of losses, of the Class A common stock and Class B common stock are identical, other than voting rights. As the liquidation and dividend rights and sharing of losses are identical, the undistributed earnings are allocated on a proportionate basis and the resulting net loss per share attributed to common stockholders will, therefore, be the same for both Class A and Class B common stock on an individual or combined basis. For periods in which the Company reports net losses, diluted net loss per share attributable to common stockholders is the same as basic net loss per share attributable to common stockholders, because potentially dilutive common shares are not assumed to have been issued if their effect is anti-dilutive. Accounting Pronouncements Recently Adopted In August 2018, the Financial Accounting Standards Board (“FASB”) issued ASU No. 2018-15, Intangibles—Goodwill and Other—Internal-use Software (Subtopic 350-40): Customer’s Accounting for Implementation Costs Incurred in a Cloud Computing Arrangement that is a Service Contract. The Company adopted ASU 2018-15 as of January 1, 2021. The adoption of ASU 2018-15 did not have a material impact on the Company’s condensed consolidated financial statements. In August 2020, the FASB issued ASU 2020-06, Debt – Debt with Conversion and Other Options (Subtopic 470-20) and Derivative and Hedging – Contracts in Entity’s Own Equity (Subtopic 815-40) . The Company adopted ASU 2020-06 on January 1, 2021. The adoption of this ASU did not have any impact on the Company’s condensed consolidated financial statements. In June 2016, the FASB issued ASU 2016-13, Financial Instruments - Credit Losses (Topic 326): Measurement of Credit Losses on Financial Instruments

Fair Value Measurements

Fair Value Measurements	3 Months Ended
	Mar. 31, 2021
Fair Value Disclosures [Abstract]
Fair Value Measurements	Fair Value Measurements The following tables provide the financial instruments measured at fair value for each of the respective periods (in thousands): March 31, 2021 Level 1 Level 2 Level 3 Total Assets Cash equivalents: Money market fund $ 224,268 $ — $ — $ 224,268 Total cash equivalents $ 224,268 $ — $ — $ 224,268 December 31, 2020 Level 1 Level 2 Level 3 Total Assets Cash equivalents: Money market fund $ 43,460 $ — $ — $ 43,460 Total cash equivalents $ 43,460 $ — $ — $ 43,460 Liabilities Convertible preferred stock warrant liability $ — $ — $ 805 $ 805 Total liabilities $ — $ — $ 805 $ 805 There were no transfers in or out of Level 1 or 2 during the periods presented in the tables above. The Company’s money market funds are classified as Level 1 because they are valued using quoted market prices. As of March 31, 2021 and December 31, 2020, the amortized cost of the Company’s financial assets and liabilities approximate their estimated fair values. As such, there are no unrealized gains or losses related to the Company’s financial assets and liabilities.

Property and Equipment, Net

Property and Equipment, Net	3 Months Ended
	Mar. 31, 2021
Property, Plant and Equipment [Abstract]
Property and Equipment, Net	Property and Equipment, Net Property and equipment, net consists of the following (in thousands): March 31, December 31, 2021 2020 Property and equipment $ 59,283 $ 55,221 Less: accumulated depreciation and amortization (15,721) (14,090) Property and equipment, net $ 43,562 $ 41,131

Other Balance Sheet Details

Other Balance Sheet Details	3 Months Ended
	Mar. 31, 2021
Other Liabilities [Abstract]
Other Balance Sheet Details	Other Balance Sheet Details Accrued and other current liabilities consist of the following (in thousands): March 31, December 31, 2021 2020 Gift card and site credit liabilities $ 9,633 $ 9,362 Deferred revenue 4,949 5,094 Allowance for returns 4,604 3,389 Accrued taxes 4,595 4,594 Accrued compensation 4,409 3,443 Accrued vendor liabilities 4,288 3,407 Accrued marketing 3,976 1,648 Accrued other 1,266 1,604 $ 37,720 $ 32,541

Lease Agreements

Lease Agreements	3 Months Ended
	Mar. 31, 2021
Leases [Abstract]
Lease Agreements	Lease Agreements For the three months ended March 31, 2021 and 2020, the Company’s operating lease expense was $2.1 million and $1.4 million, respectively. Maturities of operating lease liabilities were as follows as of March 31, 2021 (in thousands): Amount Remainder of 2021 $ 3,456 2022 4,519 2023 4,508 2024 4,156 2025 2,760 Thereafter 12,292 Total lease payments 31,691 Less: imputed interest 7,785 Total lease liabilities 23,906 Less: current lease liabilities 3,095 Total non-current lease liabilities $ 20,811

Long-term Debt and Convertible

Long-term Debt and Convertible Preferred Stock Warrants	3 Months Ended
	Mar. 31, 2021
Debt Disclosure [Abstract]
Long-term Debt and Convertible Preferred Stock Warrants	Long-term Debt and Convertible Preferred Stock Warrants The Company entered into a loan and security agreement (“Term Loan”) with Western Alliance Bank (“Bank”) for an aggregate amount up to $40.0 million to refinance its Loan and Security Agreement with Silicon Valley Bank (“SVB”) in February 2019. The Term Loan was amended three times before December 31, 2020. In February 2021, the Company amended and restated the loan and security agreement (“Fourth Amendment”) with the Bank to reflect all waivers and amendments to date. Subsequently, the Company borrowed an additional $5.0 million for an aggregate principal amount of $40.0 million. In connection with the additional $5.0 million draw, the Company issued additional warrant shares for Series E-1 preferred stock in the amount of 15,979 or (i) two percent of the additional advance amount drawn under the Term A Loans, divided by (ii) the applicable exercise price at the time the warrant is exercised. As of March 31, 2021, the nominal interest rate was 5.75% and the effective interest rate was 6.84%. The Company is in compliance with the covenants as of March 31, 2021. The maturities of the loan agreement as of March 31, 2021 are as follows (in thousands): Amount Remainder of 2021 $ 4,000 2022 8,000 2023 8,000 2024 20,000 Thereafter — Total future principal 40,000 Less: unamortized debt discount 944 Less: current portion of long-term debt 5,736 Noncurrent portion of long-term debt $ 33,320 Warrants Issued with Loan and Security Agreement The Company issued various preferred stock warrants under its loan and security agreements with SVB and the Bank. Immediately prior to the conversion upon IPO and as of December 31, 2020, the following preferred stock warrant liabilities were outstanding. Description Issuance Date Expiration Date Balance Sheet Classification Exercise Price Per Share Immediately Prior to the Completion of IPO December 31, 2020 Series D 1/22/2015 1/22/2025 Liability $ 2.2600 13,382 13,382 Series D 4/20/2015 1/22/2025 Liability $ 2.2600 13,382 13,382 Series E-1 2/7/2019 5/29/2030 Liability $ 6.2581 63,917 63,917 Series F 5/29/2020 5/29/2030 Liability $ 6.8839 10,376 10,376 Series E-1 8/14/2020 5/29/2030 Liability $ 6.2581 31,958 31,958 Series E-1 11/25/2020 5/29/2030 Liability $ 6.2581 15,979 15,979 Series E-1 2/8/2021 5/29/2030 Liability $ 6.2581 15,979 — 164,973 148,994 The convertible preferred stock warrant liability of $0.8 million was included in other non-current liabilities in the consolidated balance sheet as of December 31, 2020. Immediately prior to the completion of IPO in March 2021, all 164,973 shares of the convertible preferred stock warrant were remeasured to fair value and converted to equivalent number of Class B common stock warrants. The Company reclassified the convertible preferred stock warrant liability to additional paid-in capital upon the conversion. Refer to Note 8. Common Stock and Common Stock Warrants for more details on common stock warrants.

Common Stock and Common Stock W

Common Stock and Common Stock Warrants	3 Months Ended
	Mar. 31, 2021
Equity [Abstract]
Common Stock and Common Stock Warrants	Common Stock and Common Stock Warrants Each share of Class A common stock is entitled to one vote per share. Each share of Class B common stock is entitled to ten votes per share and is convertible at any time into one share of Class A common stock. Immediately prior to the completion of the IPO, 65,970,938 shares of the convertible preferred stock converted to an equivalent number of shares of Class B common stock and 164,973 shares of the convertible preferred stock warrants were converted to an equivalent number of Class B common stock warrants. During the three months ended March 31, 2021, the Company issued 24,837 shares of Class B common stock through a cashless net exercise of 26,764 shares of Class B common stock warrants. 138,209 shares of Class B common stock warrants were outstanding as of March 31, 2021. The table below summarizes the Class A common stock and Class B common stock issued and outstanding as of March 31, 2021. As of March 31, 2021 Authorized Issued and Outstanding Common stock Class A 1,000,000,000 13,800,000 Common stock Class B 120,000,000 80,343,694 Total common stock 1,120,000,000 94,143,694

Stock-Based Compensation Plans

Stock-Based Compensation Plans	3 Months Ended
	Mar. 31, 2021
Share-based Payment Arrangement [Abstract]
Stock-Based Compensation Plans	Stock-Based Compensation Plans 2021 Stock Option and Incentive Plan In February 2021, in connection with the IPO, the Company’s board of directors adopted the 2021 Stock Option and Incentive Plan (“2021 Plan”) to replace the Second Amended and Restated 2010 Stock Plan (“2010 Plan”), which was subsequently approved by the Company’s stockholders in March 2021. The 2021 Plan became effective on March 24, 2021. As of March 31, 2021, no stock options were granted under the 2021 Plan. As of March 31, 2021, 96,426 restricted stock units were granted under the 2021 Plan. 2021 Employee Stock Purchase Plan In February 2021, the Company’s board of directors adopted the Employee Stock Purchase Plan (“ESPP”), which was subsequently approved by the stockholders in March 2021. The ESPP became effective on March 24, 2021. The first offering period began on March 25, 2021, and there was no stock-based compensation related to the ESPP for the three months ended March 31, 2021. IPO Options Under the 2010 Plan In August 2020, the Company’s board of directors approved stock options for 3,588,535 common shares to be granted to certain officers and employees with an exercise price of $2.05 per share. 50% of the options granted vest over a four -year period commencing on the effective date of the IPO. The remaining 50% of the options granted vest over a four -year period commencing on the one -year anniversary of the IPO. As these stock options vest upon the satisfaction of both a time-based condition and a performance condition, the fair value of these stock options of $6.7 million, in aggregate, will be recognized as compensation expense over the requisite service period using the accelerated attribution method . In the three months ended in March 31, 2021, $1.6 million was recognized as compensation expense from such stock options subject to these performance conditions. Stock-based Compensation Total stock-based compensation expense by department is as follows (in thousands): Three months ended March 31, 2021 2020 Operations, product and technology $ 1,350 $ 714 Marketing 437 174 Sales, general and administrative 1,711 554 Total stock-based compensation expense $ 3,498 $ 1,442 As of March 31, 2021, there was approximately $20.1 million of total unrecognized stock-based compensation expense related to unvested options granted to employees under the Company’s stock option plan that is expected to be recognized over a weighted average period of 1.56 years.

Commitment and Contingencies

Commitment and Contingencies	3 Months Ended
	Mar. 31, 2021
Commitments and Contingencies Disclosure [Abstract]
Commitments and Contingencies	Commitments and Contingencies Legal Contingencies The Company is subject to litigation claims and assessments from time to time in the ordinary course of business. The Company’s management does not believe that any such matters, individually or in the aggregate, will have a material adverse effect on the Company’s business, financial condition, results of operations, or cash flows. Indemnifications

Income Taxes

Income Taxes	3 Months Ended
	Mar. 31, 2021
Income Tax Disclosure [Abstract]
Income Taxes	Income TaxesThe quarterly income tax provision reflects an estimate of the corresponding quarter’s state taxes in the United States. The provision for income tax expense for the three months ended March 31, 2021 and 2020 was determined based upon estimates of the Company’s annual effective tax rate for the years ending December 31, 2021 and 2020 respectively. Since the company is in a full valuation allowance position, due to losses incurred since inception, the provision for taxes consist solely of state minimum taxes. The Company has no uncertain tax positions or any unrecognized tax benefits.

Net Loss Per Share Attributable

Net Loss Per Share Attributable to Common Stockholders	3 Months Ended
	Mar. 31, 2021
Earnings Per Share [Abstract]
Net Loss Per Share Attributable to Common Stockholders	Net Loss Per Share Attributable to Common Stockholders The following participating securities were excluded from the computation of diluted net loss per share attributable to common stockholders for the periods presented, because including them would have been anti-dilutive (on an as-converted basis): As of March 31, 2021 2020 Outstanding stock options 22,067,610 19,886,677 Outstanding Class B common stock warrants 138,209 — Restricted stock units 96,426 — Convertible preferred stock — 65,928,261 Outstanding convertible preferred stock warrants — 170,975 Total 22,302,245 85,985,913

Significant Accounting Polici_2

Significant Accounting Policies (Policies)	3 Months Ended
	Mar. 31, 2021
Accounting Policies [Abstract]
Basis of Presentation	The accompanying condensed consolidated financial statements include the accounts of the Company and its wholly-owned subsidiaries. All intercompany account balances and transactions have been eliminated upon consolidation. The unaudited condensed consolidated financial statements were prepared in accordance with generally accepted accounting principles (“GAAP”) in the United States for interim financial information and with the instructions to Form 10‑Q and Article 10 of Regulation S-X. As permitted under those rules, certain footnotes or other financial information can be condensed or omitted.
Use of Estimates	The preparation of consolidated financial statements in conformity with GAAP requires management to make estimates and assumptions that affect the amounts that are reported in the consolidated financial statements and the related disclosures. Actual results could differ from those estimates. Significant items subject to such estimates and assumptions include, but are not limited to, the useful lives of property and equipment, allowance for sales returns, allowance for bad debts, breakage on loyalty points and rewards, valuation of inventory, warrants, stock-based compensation, valuation of right-of-use assets and income taxes.
Net Loss Per Share Attributable to Common Stockholders	The Company follows the two-class method when computing net loss per common share when shares issued meet the definition of participating securities. The rights, including the liquidation and dividend rights and sharing of losses, of the Class A common stock and Class B common stock are identical, other than voting rights. As the liquidation and dividend rights and sharing of losses are identical, the undistributed earnings are allocated on a proportionate basis and the resulting net loss per share attributed to common stockholders will, therefore, be the same for both Class A and Class B common stock on an individual or combined basis. For periods in which the Company reports net losses, diluted net loss per share attributable to common stockholders is the same as basic net loss per share attributable to common stockholders, because potentially dilutive common shares are not assumed to have been issued if their effect is anti-dilutive.
Accounting Pronouncements Recently Adopted and New Accounting Pronouncements Recently Issue But Not Yet Adopted	In August 2018, the Financial Accounting Standards Board (“FASB”) issued ASU No. 2018-15, Intangibles—Goodwill and Other—Internal-use Software (Subtopic 350-40): Customer’s Accounting for Implementation Costs Incurred in a Cloud Computing Arrangement that is a Service Contract. The Company adopted ASU 2018-15 as of January 1, 2021. The adoption of ASU 2018-15 did not have a material impact on the Company’s condensed consolidated financial statements. In August 2020, the FASB issued ASU 2020-06, Debt – Debt with Conversion and Other Options (Subtopic 470-20) and Derivative and Hedging – Contracts in Entity’s Own Equity (Subtopic 815-40) . The Company adopted ASU 2020-06 on January 1, 2021. The adoption of this ASU did not have any impact on the Company’s condensed consolidated financial statements. In June 2016, the FASB issued ASU 2016-13, Financial Instruments - Credit Losses (Topic 326): Measurement of Credit Losses on Financial Instruments
Fair Value Measurements	The Company’s money market funds are classified as Level 1 because they are valued using quoted market prices.

Significant Accounting Polici_3

Significant Accounting Policies (Tables)	3 Months Ended
	Mar. 31, 2021
Accounting Policies [Abstract]
Schedule of Cash and Cash Equivalents	The following table provides a reconciliation of cash, cash equivalents and restricted cash and cash equivalents reported within the condensed consolidated balance sheets to the amounts shown in the condensed consolidated statements of cash flows (in thousands): March 31, December 31, 2021 2020 Cash and cash equivalents $ 246,514 $ 64,485 Restricted cash and cash equivalents, current and non-current 3,054 3,054 Total cash, cash equivalents and restricted cash and cash equivalents $ 249,568 $ 67,539
Restrictions on Cash and Cash Equivalents	The following table provides a reconciliation of cash, cash equivalents and restricted cash and cash equivalents reported within the condensed consolidated balance sheets to the amounts shown in the condensed consolidated statements of cash flows (in thousands): March 31, December 31, 2021 2020 Cash and cash equivalents $ 246,514 $ 64,485 Restricted cash and cash equivalents, current and non-current 3,054 3,054 Total cash, cash equivalents and restricted cash and cash equivalents $ 249,568 $ 67,539

Fair Value Measurements (Tables

Fair Value Measurements (Tables)	3 Months Ended
	Mar. 31, 2021
Fair Value Disclosures [Abstract]
Schedule of Financial Instruments Measured at Fair Value	The following tables provide the financial instruments measured at fair value for each of the respective periods (in thousands): March 31, 2021 Level 1 Level 2 Level 3 Total Assets Cash equivalents: Money market fund $ 224,268 $ — $ — $ 224,268 Total cash equivalents $ 224,268 $ — $ — $ 224,268 December 31, 2020 Level 1 Level 2 Level 3 Total Assets Cash equivalents: Money market fund $ 43,460 $ — $ — $ 43,460 Total cash equivalents $ 43,460 $ — $ — $ 43,460 Liabilities Convertible preferred stock warrant liability $ — $ — $ 805 $ 805 Total liabilities $ — $ — $ 805 $ 805

Property and Equipment, Net (Ta

Property and Equipment, Net (Tables)	3 Months Ended
	Mar. 31, 2021
Property, Plant and Equipment [Abstract]
Schedule of Property and Equipment, Net	Property and equipment, net consists of the following (in thousands): March 31, December 31, 2021 2020 Property and equipment $ 59,283 $ 55,221 Less: accumulated depreciation and amortization (15,721) (14,090) Property and equipment, net $ 43,562 $ 41,131

Other Balance Sheet Details (Ta

Other Balance Sheet Details (Tables)	3 Months Ended
	Mar. 31, 2021
Other Liabilities [Abstract]
Schedule of Other Current Liabilities	Accrued and other current liabilities consist of the following (in thousands): March 31, December 31, 2021 2020 Gift card and site credit liabilities $ 9,633 $ 9,362 Deferred revenue 4,949 5,094 Allowance for returns 4,604 3,389 Accrued taxes 4,595 4,594 Accrued compensation 4,409 3,443 Accrued vendor liabilities 4,288 3,407 Accrued marketing 3,976 1,648 Accrued other 1,266 1,604 $ 37,720 $ 32,541

Lease Agreements (Tables)

Lease Agreements (Tables)	3 Months Ended
	Mar. 31, 2021
Leases [Abstract]
Maturities of Operating Lease Liabilities	Maturities of operating lease liabilities were as follows as of March 31, 2021 (in thousands): Amount Remainder of 2021 $ 3,456 2022 4,519 2023 4,508 2024 4,156 2025 2,760 Thereafter 12,292 Total lease payments 31,691 Less: imputed interest 7,785 Total lease liabilities 23,906 Less: current lease liabilities 3,095 Total non-current lease liabilities $ 20,811

Long-term Debt and Convertibl_2

Long-term Debt and Convertible Preferred Stock Warrants (Tables)	3 Months Ended
	Mar. 31, 2021
Debt Disclosure [Abstract]
Schedule of Maturities of Debt	The maturities of the loan agreement as of March 31, 2021 are as follows (in thousands): Amount Remainder of 2021 $ 4,000 2022 8,000 2023 8,000 2024 20,000 Thereafter — Total future principal 40,000 Less: unamortized debt discount 944 Less: current portion of long-term debt 5,736 Noncurrent portion of long-term debt $ 33,320
Schedule of Warrants Issued	Description Issuance Date Expiration Date Balance Sheet Classification Exercise Price Per Share Immediately Prior to the Completion of IPO December 31, 2020 Series D 1/22/2015 1/22/2025 Liability $ 2.2600 13,382 13,382 Series D 4/20/2015 1/22/2025 Liability $ 2.2600 13,382 13,382 Series E-1 2/7/2019 5/29/2030 Liability $ 6.2581 63,917 63,917 Series F 5/29/2020 5/29/2030 Liability $ 6.8839 10,376 10,376 Series E-1 8/14/2020 5/29/2030 Liability $ 6.2581 31,958 31,958 Series E-1 11/25/2020 5/29/2030 Liability $ 6.2581 15,979 15,979 Series E-1 2/8/2021 5/29/2030 Liability $ 6.2581 15,979 — 164,973 148,994

Common Stock and Common Stock_2

Common Stock and Common Stock Warrants (Tables)	3 Months Ended
	Mar. 31, 2021
Equity [Abstract]
Schedule of Common Stock Issued and Outstanding	The table below summarizes the Class A common stock and Class B common stock issued and outstanding as of March 31, 2021. As of March 31, 2021 Authorized Issued and Outstanding Common stock Class A 1,000,000,000 13,800,000 Common stock Class B 120,000,000 80,343,694 Total common stock 1,120,000,000 94,143,694

Stock-Based Compensation Plans

Stock-Based Compensation Plans (Tables)	3 Months Ended
	Mar. 31, 2021
Share-based Payment Arrangement [Abstract]
Schedule of Stock-based Compensation Expense	Total stock-based compensation expense by department is as follows (in thousands): Three months ended March 31, 2021 2020 Operations, product and technology $ 1,350 $ 714 Marketing 437 174 Sales, general and administrative 1,711 554 Total stock-based compensation expense $ 3,498 $ 1,442

Net Loss Per Share Attributab_2

Net Loss Per Share Attributable to Common Stockholders (Tables)	3 Months Ended
	Mar. 31, 2021
Earnings Per Share [Abstract]
Schedule of Participating Securities Excluded From the Computation of Diluted Net Loss Per Share	The following participating securities were excluded from the computation of diluted net loss per share attributable to common stockholders for the periods presented, because including them would have been anti-dilutive (on an as-converted basis): As of March 31, 2021 2020 Outstanding stock options 22,067,610 19,886,677 Outstanding Class B common stock warrants 138,209 — Restricted stock units 96,426 — Convertible preferred stock — 65,928,261 Outstanding convertible preferred stock warrants — 170,975 Total 22,302,245 85,985,913

Organization and Description _2

Organization and Description of Business (Details) - USD ($) $ / shares in Units, $ in Thousands	Mar. 26, 2021	Mar. 31, 2021	Mar. 31, 2020	Mar. 25, 2021	Dec. 31, 2020
Class of Stock [Line Items]
Payment of costs for the initial public offering	$ 17,700	$ 1,733	$ 81
Common stock, shares authorized (in shares)		1,120,000,000			110,000,000
Shares authorized (in shares)	100,000,000	100,000,000			68,139,958
Warrants outstanding (in shares)				164,973	148,994
Class B Common Stock Warrant
Class of Stock [Line Items]
Warrants outstanding (in shares)	164,973	138,209		164,973
Common Stock
Class of Stock [Line Items]
Stock converted (in shares)	65,970,938
Conversion of stock (in shares)	12,889,760
Common stock Class A
Class of Stock [Line Items]
Common stock, shares authorized (in shares)	1,000,000,000	1,000,000,000
Common stock Class B
Class of Stock [Line Items]
Common stock, shares authorized (in shares)	120,000,000	120,000,000
Stock converted (in shares)		26,764
IPO
Class of Stock [Line Items]
Shares sold (in shares)	13,800,000
Price per share of common stock (in dollars per share)	$ 14
Aggregate net proceeds	$ 175,500
Over-Allotment Option
Class of Stock [Line Items]
Shares sold (in shares)	1,800,000

Significant Accounting Polici_4

Significant Accounting Policies - Narrative (Details) - USD ($) $ in Millions	3 Months Ended
	Mar. 31, 2021	Mar. 31, 2020	Dec. 31, 2020
Revenue from External Customer [Line Items]
Restricted cash and cash equivalents, non-current	$ 2.7		$ 2.7
Loyalty Program
Revenue from External Customer [Line Items]
Revenue recognized	$ 3.3	$ 0.2

Significant Accounting Polici_5

Significant Accounting Policies - Cash, Cash Equivalents and Restricted Cash and Cash Equivalents (Details) - USD ($) $ in Thousands	Mar. 31, 2021	Dec. 31, 2020	Mar. 31, 2020	Dec. 31, 2019
Accounting Policies [Abstract]
Cash and cash equivalents	$ 246,514	$ 64,485
Restricted cash and cash equivalents, current and non-current	3,054	3,054
Total cash, cash equivalents and restricted cash and cash equivalents	$ 249,568	$ 67,539	$ 73,293	$ 87,853

Fair Value Measurements - Sched

Fair Value Measurements - Schedule of Financial Instruments Measured at Fair Value (Details) - USD ($) $ in Thousands	Mar. 31, 2021	Dec. 31, 2020
Liabilities
Convertible preferred stock warrant liability		$ 800
Fair Value, Recurring
Cash equivalents:
Total cash equivalents	$ 224,268	43,460
Liabilities
Convertible preferred stock warrant liability		805
Total liabilities		805
Fair Value, Recurring | Money market fund
Cash equivalents:
Total cash equivalents	224,268	43,460
Fair Value, Recurring | Level 1
Cash equivalents:
Total cash equivalents	224,268	43,460
Liabilities
Convertible preferred stock warrant liability		0
Total liabilities		0
Fair Value, Recurring | Level 1 | Money market fund
Cash equivalents:
Total cash equivalents	224,268	43,460
Fair Value, Recurring | Level 2
Cash equivalents:
Total cash equivalents	0	0
Liabilities
Convertible preferred stock warrant liability		0
Total liabilities		0
Fair Value, Recurring | Level 2 | Money market fund
Cash equivalents:
Total cash equivalents	0	0
Fair Value, Recurring | Level 3
Cash equivalents:
Total cash equivalents	0	0
Liabilities
Convertible preferred stock warrant liability		805
Total liabilities		805
Fair Value, Recurring | Level 3 | Money market fund
Cash equivalents:
Total cash equivalents	$ 0	$ 0

Property and Equipment, Net - S

Property and Equipment, Net - Schedule of Property and Equipment, Net (Details) - USD ($) $ in Thousands	Mar. 31, 2021	Dec. 31, 2020
Property, Plant and Equipment [Abstract]
Property and equipment	$ 59,283	$ 55,221
Less: accumulated depreciation and amortization	(15,721)	(14,090)
Property and equipment, net	$ 43,562	$ 41,131

Property and Equipment, Net - N

Property and Equipment, Net - Narrative (Details) - USD ($) $ in Millions	3 Months Ended
	Mar. 31, 2021	Mar. 31, 2020
Property, Plant and Equipment [Abstract]
Capitalized internal-use software	$ 0.5	$ 0.3
Interests costs capitalized	0.1	0.1
Interests costs	0.6	0.3
Depreciation	$ 2	$ 1.2

Other Balance Sheet Details (De

Other Balance Sheet Details (Details) - USD ($) $ in Thousands	Mar. 31, 2021	Dec. 31, 2020
Other Liabilities [Abstract]
Gift card and site credit liabilities	$ 9,633	$ 9,362
Deferred revenue	4,949	5,094
Allowance for returns	4,604	3,389
Accrued taxes	4,595	4,594
Accrued compensation	4,409	3,443
Accrued vendor liabilities	4,288	3,407
Accrued marketing	3,976	1,648
Accrued other	1,266	1,604
Total	$ 37,720	$ 32,541

Lease Agreements - Narrative (D

Lease Agreements - Narrative (Details) - USD ($) $ in Millions	3 Months Ended
	Mar. 31, 2021	Mar. 31, 2020
Leases [Abstract]
Operating lease expense	$ 2.1	$ 1.4

Lease Agreements - Maturities o

Lease Agreements - Maturities of Operating Lease Liabilities (Details) - USD ($) $ in Thousands	Mar. 31, 2021	Dec. 31, 2020
Leases [Abstract]
Remainder of 2021	$ 3,456
2022	4,519
2023	4,508
2024	4,156
2025	2,760
Thereafter	12,292
Total lease payments	31,691
Less: imputed interest	7,785
Total lease liabilities	23,906
Less: current lease liabilities	3,095	$ 3,643
Total non-current lease liabilities	$ 20,811	$ 21,574

Long-term Debt and Convertibl_3

Long-term Debt and Convertible Preferred Stock Warrants - Narrative (Details) - USD ($)	1 Months Ended
	Feb. 28, 2021	Mar. 31, 2021	Mar. 26, 2021	Mar. 25, 2021	Dec. 31, 2020
Debt Instrument [Line Items]
Outstanding principal		$ 40,000,000
Convertible preferred stock warrant liability					$ 800,000
Warrants outstanding (in shares)				164,973	148,994
Class B Common Stock Warrant
Debt Instrument [Line Items]
Warrants outstanding (in shares)		138,209	164,973	164,973
Term Loan | Series E-1 Convertible Preferred Stock
Debt Instrument [Line Items]
Warrants converted (in shares)	15,979
Percent of additional advance amount drawn	2.00%
Medium-term Notes | Term Loan
Debt Instrument [Line Items]
Maximum borrowing capacity	$ 40,000,000
Borrowed amount	5,000,000
Outstanding principal	$ 40,000,000
Stated interest rate		5.75%
Effective interest rate		6.84%

Long-term Debt and Convertibl_4

Long-term Debt and Convertible Preferred Stock Warrants - Schedule of Maturities of Debt (Details) - USD ($) $ in Thousands	Mar. 31, 2021	Dec. 31, 2020
Debt Disclosure [Abstract]
Remainder of 2021	$ 4,000
2022	8,000
2023	8,000
2024	20,000
Thereafter	0
Total future principal	40,000
Less: unamortized debt discount	944
Less: current portion of long-term debt	5,736	$ 3,270
Noncurrent portion of long-term debt	$ 33,320	$ 31,190

Long-term Debt and Convertibl_5

Long-term Debt and Convertible Preferred Stock Warrants - Schedule of Warrants Issued (Details) - $ / shares	Mar. 25, 2021	Dec. 31, 2020
Debt Instrument [Line Items]
Warrants outstanding (in shares)	164,973	148,994
Series D Convertible Preferred Stock, Issued 1/22/2015
Debt Instrument [Line Items]
Exercise price (in dollars per share)	$ 2.2600
Warrants outstanding (in shares)	13,382	13,382
Series D Convertible Preferred Stock, Issued 4/20/2015
Debt Instrument [Line Items]
Exercise price (in dollars per share)	$ 2.2600
Warrants outstanding (in shares)	13,382	13,382
Series E1 Convertible Preferred Stock, Issued 2/7/2019
Debt Instrument [Line Items]
Exercise price (in dollars per share)	$ 6.2581
Warrants outstanding (in shares)	63,917	63,917
Series F Convertible Preferred Stock, Issued 5/29/2020
Debt Instrument [Line Items]
Exercise price (in dollars per share)	$ 6.8839
Warrants outstanding (in shares)	10,376	10,376
Series E1 Convertible Preferred Stock, Issued 8/14/2020
Debt Instrument [Line Items]
Exercise price (in dollars per share)	$ 6.2581
Warrants outstanding (in shares)	31,958	31,958
Series E1 Convertible Preferred Stock, Issued 11/25/2020
Debt Instrument [Line Items]
Exercise price (in dollars per share)	$ 6.2581
Warrants outstanding (in shares)	15,979	15,979
Series E1 Convertible Preferred Stock, Issued 2/28/2021
Debt Instrument [Line Items]
Exercise price (in dollars per share)	$ 6.2581
Warrants outstanding (in shares)	15,979	0

Common Stock and Common Stock_3

Common Stock and Common Stock Warrants - Narrative (Details)	Mar. 26, 2021voteshares	Mar. 31, 2021shares	Mar. 25, 2021shares	Dec. 31, 2020shares
Class of Stock [Line Items]
Warrants outstanding (in shares)			164,973	148,994
Common Stock
Class of Stock [Line Items]
Stock converted (in shares)	65,970,938
Cashless exercise of common stock warrant (in shares)		24,837
Class B Common Stock Warrant
Class of Stock [Line Items]
Warrants outstanding (in shares)	164,973	138,209	164,973
Common stock Class A
Class of Stock [Line Items]
Number of votes for each share | vote	1
Common stock Class B
Class of Stock [Line Items]
Number of votes for each share | vote	10
Conversion of stock (in shares)	1
Stock converted (in shares)		26,764

Common Stock and Common Stock_4

Common Stock and Common Stock Warrants - Schedule of Common Stock Issued and Outstanding (Details) - shares	Mar. 31, 2021	Mar. 26, 2021	Dec. 31, 2020
Class of Stock [Line Items]
Authorized (in shares)	1,120,000,000		110,000,000
Issued (in shares)	94,143,694		12,889,760
Outstanding (in shares)	94,143,694		12,889,760
Common stock Class A
Class of Stock [Line Items]
Authorized (in shares)	1,000,000,000	1,000,000,000
Issued (in shares)	13,800,000
Outstanding (in shares)	13,800,000
Common stock Class B
Class of Stock [Line Items]
Authorized (in shares)	120,000,000	120,000,000
Issued (in shares)	80,343,694
Outstanding (in shares)	80,343,694

Stock-Based Compensation Plan_2

Stock-Based Compensation Plans - Narrative (Details) - USD ($)	1 Months Ended	3 Months Ended
	Aug. 31, 2020	Mar. 31, 2021	Mar. 31, 2020
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Compensation expense		$ 3,498,000	$ 1,442,000
Unrecognized stock-based compensation expense		$ 20,100,000
2021 Plan
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Options granted (in shares)		0
2010 Plan
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Options granted (in shares)	3,588,535
Options granted (in dollars per share)	$ 2.05
Fair value of stock options	$ 6,700,000
Restricted stock units | 2021 Plan
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
RSUs granted (in shares)		96,426
Employee Stock
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Compensation expense		$ 0
Options
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Weighted average period for unrecognized stock-based compensation expense		1 year 6 months 21 days
Options | 2010 Plan
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Compensation expense		$ 1,600,000
Option Vesting Four Years From Commencement | 2010 Plan
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Vesting percentage	50.00%
Vesting percentage period	4 years
Option Vesting Four Years From IPO | 2010 Plan
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Vesting percentage	50.00%
Vesting percentage period	4 years
Anniversary period	1 year

Stock-Based Compensation Plan_3

Stock-Based Compensation Plans - Schedule of Stock-Based Compensation Expense (Details) - USD ($) $ in Thousands	3 Months Ended
	Mar. 31, 2021	Mar. 31, 2020
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Total stock-based compensation expense	$ 3,498	$ 1,442
Operations, product and technology
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Total stock-based compensation expense	1,350	714
Marketing
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Total stock-based compensation expense	437	174
Sales, general and administrative
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Total stock-based compensation expense	$ 1,711	$ 554

Income Taxes (Details)

Income Taxes (Details)	Mar. 31, 2021USD ($)
Income Tax Disclosure [Abstract]
Unrecognized tax benefits	$ 0

Net Loss Per Share Attributab_3

Net Loss Per Share Attributable to Common Stockholders (Details) - shares	3 Months Ended
	Mar. 31, 2021	Mar. 31, 2020
Antidilutive Securities Excluded from Computation of Earnings Per Share [Line Items]
Total (in shares)	22,302,245	85,985,913
Outstanding stock options
Antidilutive Securities Excluded from Computation of Earnings Per Share [Line Items]
Total (in shares)	22,067,610	19,886,677
Warrants
Antidilutive Securities Excluded from Computation of Earnings Per Share [Line Items]
Total (in shares)	138,209	170,975
Restricted stock units
Antidilutive Securities Excluded from Computation of Earnings Per Share [Line Items]
Total (in shares)	96,426	0
Convertible preferred stock
Antidilutive Securities Excluded from Computation of Earnings Per Share [Line Items]
Total (in shares)	0	65,928,261

Uncategorized Items - tdup-2021

Label	Element	Value
Accounting Standards Update [Extensible Enumeration]	us-gaap_AccountingStandardsUpdateExtensibleList	Accounting Standards Update 2016-02 [Member]