Marqeta (MQ) 10-Q 10 Nov 21 2021 Q3 Quarterly report Financial data

Cover page

Cover page - shares	9 Months Ended
	Sep. 30, 2021	Nov. 05, 2021
Entity Information [Line Items]
Document Type	10-Q
Document Quarterly Report	true
Document Period End Date	Sep. 30, 2021
Document Transition Report	false
Entity File Number	001-40465
Entity Registrant Name	Marqeta, Inc.
Entity Incorporation, State or Country Code	DE
Entity Tax Identification Number	27-4306690
Entity Address, Address Line One	180 Grand Avenue
Entity Address, Address Line Two	6th Floor
Entity Address, City or Town	Oakland
Entity Address, State or Province	CA
Entity Address, Postal Zip Code	94612
City Area Code	888
Local Phone Number	462-7738
Title of 12(b) Security	Class A common stock, $0.0001 par value per share
Trading Symbol	MQ
Security Exchange Name	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
Entity Central Index Key	0001522540
Current Fiscal Year End Date	--12-31
Document Fiscal Year Focus	2021
Amendment Flag	false
Document Fiscal Period Focus	Q3
Class A Common Stock
Entity Information [Line Items]
Entity Common Stock, Shares Outstanding		232,493,282
Class B Common Stock
Entity Information [Line Items]
Entity Common Stock, Shares Outstanding		307,644,037

Condensed Consolidated Balance

Condensed Consolidated Balance Sheets (Unaudited) - USD ($) $ in Thousands	Sep. 30, 2021	Dec. 31, 2020
Current assets:
Cash and cash equivalents	$ 1,260,220	$ 220,433
Restricted cash	7,800	7,800
Marketable securities	408,954	149,903
Accounts receivable, net	7,338	8,420
Settlements receivable, net	15,451	12,867
Network incentives receivable	40,024	20,022
Prepaid expenses and other current assets	19,859	11,461
Total current assets	1,759,646	430,906
Property and equipment, net	10,191	9,477
Operating lease right-of-use assets, net	11,832	13,411
Other assets	1,473	3,886
Total assets	1,783,142	457,680
Current liabilities:
Accounts payable	2,717	2,362
Revenue share payable	88,183	78,191
Accrued expenses and other current liabilities	97,606	60,545
Total current liabilities	188,506	141,098
Redeemable convertible preferred stock warrant liabilities	0	2,517
Operating lease liabilities, net of current portion	13,218	15,449
Other liabilities	8,078	10,452
Total liabilities	209,802	169,516
Commitments and contingencies (Note 7)
Redeemable convertible preferred stock, $0.0001 par value; zero and 352,047,950 shares authorized; zero and 351,844,340 shares issued and outstanding; aggregate liquidation preference of zero and $552,868 as of September 30, 2021 and December 31, 2020, respectively	0	501,881
Stockholders’ equity (deficit):
Preferred stock, $0.0001 par value; 100,000,000 and zero shares authorized, no shares issued and outstanding as of September 30, 2021 and December 31, 2020, respectively	0	0
Common stock, $0.0001 par value: 1,500,000,000 and zero Class A shares authorized, 126,231,304 and zero shares issued and outstanding as of September 30, 2021 and December 31, 2020, respectively. 600,000,000 and 545,000,000 Class B shares authorized, 413,545,721 and 130,312,838 shares issued and outstanding as of September 30, 2021 and December 31, 2020, respectively	54	13
Additional paid-in capital	1,954,315	39,769
Accumulated other comprehensive income (loss)	(383)	25
Accumulated deficit	(380,646)	(253,524)
Total stockholders’ equity (deficit)	1,573,340	(213,717)
Total liabilities, redeemable convertible preferred stock and stockholders’ equity (deficit)	$ 1,783,142	$ 457,680

Condensed Consolidated Balanc_2

Condensed Consolidated Balance Sheets (Unaudited) Parentheticals - USD ($) $ in Thousands	Sep. 30, 2021	Dec. 31, 2020
Redeemable convertible preferred stock, par value (in dollars per share)	$ 0.0001	$ 0.0001
Redeemable convertible preferred stock, shares authorized (in shares)	0	352,047,950
Redeemable convertible preferred stock, shares issued (in shares)	0	351,844,340
Redeemable convertible preferred stock, shares outstanding (in shares)	0	351,844,340
Redeemable convertible preferred stock, liquidation preference	$ 0	$ 552,868
Preferred Stock, par value (in dollars per share)	$ 0.0001	$ 0.0001
Preferred Stock, shares authorized (in shares)	100,000,000	0
Preferred Stock, shares issued (in shares)	0
Preferred Stock, shares outstanding (in shares)	0
Class A Common Stock
Common stock, par value (in dollars per share)	$ 0.0001	$ 0.0001
Common stock, shares authorized (in shares)	1,500,000,000	0
Common stock, shares issued (in shares)	126,231,304	0
Common stock, shares, outstanding (in shares)	126,231,304	0
Class B Common Stock
Common stock, shares authorized (in shares)	600,000,000	545,000,000
Common stock, shares issued (in shares)	413,545,721	130,312,838
Common stock, shares, outstanding (in shares)	413,545,721	130,312,838

Condensed Consolidated Statemen

Condensed Consolidated Statements of Operations (Unaudited) - USD ($) $ in Thousands	3 Months Ended		9 Months Ended
	Sep. 30, 2021	Sep. 30, 2020	Sep. 30, 2021	Sep. 30, 2020
Income Statement [Abstract]
Net revenue	$ 131,512	$ 84,306	$ 361,761	$ 202,096
Costs of revenue	72,438	49,024	205,855	120,635
Gross profit	59,074	35,282	155,906	81,461
Operating expenses:
Compensation and benefits	81,219	38,231	221,262	89,114
Professional services	7,947	2,132	20,590	6,957
Technology	9,299	3,432	22,494	8,531
Occupancy	1,091	1,100	3,084	3,267
Depreciation and amortization	786	901	2,567	2,608
Marketing and advertising	490	371	1,480	1,052
Other operating expenses	3,880	1,287	8,705	3,914
Total operating expenses	104,712	47,454	280,182	115,443
Loss from operations	(45,638)	(12,172)	(124,276)	(33,982)
Other income (expense), net	(57)	(83)	(2,705)	117
Loss before income tax expense	(45,695)	(12,255)	(126,981)	(33,865)
Income tax expense	(35)	(43)	(141)	(70)
Net loss	$ (45,730)	$ (12,298)	$ (127,122)	$ (33,935)
Net loss per share attributable to common stockholders, basic (in dollars per share)	$ (0.08)	$ (0.10)	$ (0.42)	$ (0.28)
Net loss per share attributable to common stockholders, diluted (in dollars per share)	$ (0.08)	$ (0.10)	$ (0.42)	$ (0.28)
Weighted-average shares used in computing net loss per share attributable to common stockholders - Basic (in shares)	538,896,513	124,225,475	302,967,155	120,931,681
Weighted-average shares used in computing net loss per share attributable to common stockholders - Diluted (in shares)	538,896,513	124,225,475	302,967,155	120,931,681

Condensed Consolidated Statem_2

Condensed Consolidated Statements of Comprehensive Loss (Unaudited) - USD ($) $ in Thousands	3 Months Ended		9 Months Ended
	Sep. 30, 2021	Sep. 30, 2020	Sep. 30, 2021	Sep. 30, 2020
Statement of Comprehensive Income [Abstract]
Net loss	$ (45,730)	$ (12,298)	$ (127,122)	$ (33,935)
Other comprehensive income (loss), net of taxes:
Change in foreign currency translation adjustment	(10)	(2)	(36)	(38)
Change in unrealized gain (loss) on marketable securities	(285)	(141)	(372)	147
Comprehensive loss	$ (46,025)	$ (12,441)	$ (127,530)	$ (33,826)

Condensed Consolidated Statem_3

Condensed Consolidated Statement of Redeemable Convertible Preferred Stock and Stockholders' Equity (Deficit) (Unaudited) - USD ($) $ in Thousands	Total	Common Stock	Additional Paid-in Capital	Accumulated Other Comprehensive Income (loss)	Accumulated Deficit
Redeemable Convertible Preferred Stock Beginning Balance (in shares) at Dec. 31, 2019	336,843,578
Redeemable Convertible Preferred Stock Beginning Balance at Dec. 31, 2019	$ 335,748
Redeemable Convertible Preferred Stock Ending Balance (in shares) at Mar. 31, 2020	336,843,578
Redeemable Convertible Preferred Stock Ending Balance at Mar. 31, 2020	$ 335,748
Balance at the beginning of the period (in shares) at Dec. 31, 2019		118,430,031
Balance at the beginning of the period at Dec. 31, 2019	(198,406)	$ 12	$ 7,365	$ 46	$ (205,829)
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Issuance of common stock upon exercise of vested options (in shares)		2,233,220
Issuance of common stock upon exercise of vested options	$ 173		173
Issuance of common stock upon early exercise of unvested options ( in shares)	313,587
Repurchase of early exercised stock options (in shares)		(142,726)
Vesting of early exercised stock options	$ 119		119
Share-based compensation expense	3,745		3,745
Change in other comprehensive income (loss)	21			21
Net loss	(14,530)				(14,530)
Balance at the end of the period (in shares) at Mar. 31, 2020		120,834,112
Balance at the end of the period at Mar. 31, 2020	$ (208,878)	$ 12	11,402	67	(220,359)
Redeemable Convertible Preferred Stock Beginning Balance (in shares) at Dec. 31, 2019	336,843,578
Redeemable Convertible Preferred Stock Beginning Balance at Dec. 31, 2019	$ 335,748
Redeemable Convertible Preferred Stock Ending Balance (in shares) at Sep. 30, 2020	351,844,340
Redeemable Convertible Preferred Stock Ending Balance at Sep. 30, 2020	$ 501,881
Balance at the beginning of the period (in shares) at Dec. 31, 2019		118,430,031
Balance at the beginning of the period at Dec. 31, 2019	(198,406)	$ 12	7,365	46	(205,829)
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Net loss	(33,935)
Balance at the end of the period (in shares) at Sep. 30, 2020		129,085,150
Balance at the end of the period at Sep. 30, 2020	$ (211,142)	$ 13	28,454	155	(239,764)
Redeemable Convertible Preferred Stock Beginning Balance (in shares) at Mar. 31, 2020	336,843,578
Redeemable Convertible Preferred Stock Beginning Balance at Mar. 31, 2020	$ 335,748
Redeemable Convertible Preferred Stock
Issuance of Series E-1 redeemable convertible preferred stock at $8.34 per share, net of issuance costs of $8,058 (in shares)	17,991,220
Issuance of Series E-1 redeemable convertible preferred stock at $8.34 per share, net of issuance costs of $8,058	$ 143,109
Redeemable Convertible Preferred Stock Ending Balance (in shares) at Jun. 30, 2020	354,834,798
Redeemable Convertible Preferred Stock Ending Balance at Jun. 30, 2020	$ 478,857
Balance at the beginning of the period (in shares) at Mar. 31, 2020		120,834,112
Balance at the beginning of the period at Mar. 31, 2020	(208,878)	$ 12	11,402	67	(220,359)
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Issuance of common stock upon exercise of vested options (in shares)		94,685
Issuance of common stock upon exercise of vested options	44		44
Issuance of common stock upon early exercise of unvested options ( in shares)		19,584
Repurchase of early exercised stock options (in shares)		(28,206)
Vesting of early exercised stock options	294		294
Share-based compensation expense	2,918		2,918
Change in other comprehensive income (loss)	231			231
Net loss	(7,107)				(7,107)
Balance at the end of the period (in shares) at Jun. 30, 2020		120,920,175
Balance at the end of the period at Jun. 30, 2020	$ (212,498)	$ 12	14,658	298	(227,466)
Redeemable Convertible Preferred Stock
Conversion of redeemable convertible preferred stock to common stock upon initial public offering (in shares)	(5,988,994)
Conversion of redeemable convertible preferred stock to common stock upon initial public offering	$ (809)
Issuance of Series E-1 redeemable convertible preferred stock at $8.34 per share, net of issuance costs of $8,058 (in shares)	2,998,536
Issuance of Series E-1 redeemable convertible preferred stock at $8.34 per share, net of issuance costs of $8,058	$ 23,833
Redeemable Convertible Preferred Stock Ending Balance (in shares) at Sep. 30, 2020	351,844,340
Redeemable Convertible Preferred Stock Ending Balance at Sep. 30, 2020	$ 501,881
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Issuance of common stock upon exercise of vested options (in shares)		1,775,852
Issuance of common stock upon exercise of vested options	893		893
Issuance of common stock upon early exercise of unvested options ( in shares)		409,879
Conversion of redeemable convertible preferred stock to common stock upon initial public offering (in shares)		5,988,994
Conversion of redeemable convertible preferred stock to common stock upon initial public offering	809	$ 1	808
Repurchase of early exercised stock options (in shares)		(9,750)
Vesting of early exercised stock options	138		138
Share-based compensation expense	11,957		11,957
Change in other comprehensive income (loss)	(143)			(143)
Net loss	(12,298)				(12,298)
Balance at the end of the period (in shares) at Sep. 30, 2020		129,085,150
Balance at the end of the period at Sep. 30, 2020	$ (211,142)	$ 13	28,454	155	(239,764)
Redeemable Convertible Preferred Stock Beginning Balance (in shares) at Dec. 31, 2020	351,844,340
Redeemable Convertible Preferred Stock Beginning Balance at Dec. 31, 2020	$ 501,881
Redeemable Convertible Preferred Stock Ending Balance (in shares) at Mar. 31, 2021	351,844,340
Redeemable Convertible Preferred Stock Ending Balance at Mar. 31, 2021	$ 501,881
Balance at the beginning of the period (in shares) at Dec. 31, 2020		130,312,838
Balance at the beginning of the period at Dec. 31, 2020	(213,717)	$ 13	39,769	25	(253,524)
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Issuance of common stock upon exercise of vested options (in shares)		1,904,186
Issuance of common stock upon exercise of vested options	1,410		1,410
Issuance of common stock upon early exercise of unvested options ( in shares)		319,883
Repurchase of early exercised stock options (in shares)		(18,567)
Vesting of early exercised stock options	223		223
Share-based compensation expense	11,392		11,392
Change in other comprehensive income (loss)	(45)			(45)
Net loss	(12,838)				(12,838)
Balance at the end of the period (in shares) at Mar. 31, 2021		132,518,340
Balance at the end of the period at Mar. 31, 2021	$ (213,575)	$ 13	52,794	(20)	(266,362)
Redeemable Convertible Preferred Stock Beginning Balance (in shares) at Dec. 31, 2020	351,844,340
Redeemable Convertible Preferred Stock Beginning Balance at Dec. 31, 2020	$ 501,881
Redeemable Convertible Preferred Stock Ending Balance (in shares) at Sep. 30, 2021	0
Redeemable Convertible Preferred Stock Ending Balance at Sep. 30, 2021	$ 0
Balance at the beginning of the period (in shares) at Dec. 31, 2020		130,312,838
Balance at the beginning of the period at Dec. 31, 2020	(213,717)	$ 13	39,769	25	(253,524)
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Net loss	(127,122)
Balance at the end of the period (in shares) at Sep. 30, 2021		539,777,025
Balance at the end of the period at Sep. 30, 2021	$ 1,573,340	$ 54	1,954,315	(383)	(380,646)
Redeemable Convertible Preferred Stock Beginning Balance (in shares) at Mar. 31, 2021	351,844,340
Redeemable Convertible Preferred Stock Beginning Balance at Mar. 31, 2021	$ 501,881
Redeemable Convertible Preferred Stock
Conversion of redeemable convertible preferred stock to common stock upon initial public offering (in shares)	(351,844,340)
Conversion of redeemable convertible preferred stock to common stock upon initial public offering	$ (501,881)
Redeemable Convertible Preferred Stock Ending Balance (in shares) at Jun. 30, 2021	0
Redeemable Convertible Preferred Stock Ending Balance at Jun. 30, 2021	$ 0
Balance at the beginning of the period (in shares) at Mar. 31, 2021		132,518,340
Balance at the beginning of the period at Mar. 31, 2021	(213,575)	$ 13	52,794	(20)	(266,362)
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Issuance of common stock upon exercise of vested options (in shares)		859,343
Issuance of common stock upon exercise of vested options	1,161		1,161
Issuance of common stock upon Initial public offering, net of issuance costs (in shares)		52,272,727
Issuance of common stock upon initial public offering, net of issuance costs	1,312,338	$ 7	1,312,331
Conversion of redeemable convertible preferred stock to common stock upon initial public offering (in shares)		351,844,340
Conversion of redeemable convertible preferred stock to common stock upon initial public offering	501,881	$ 34	501,847
Reclassification of redeemable convertible preferred stock warrant liabilities to common stock and additional paid-in capital upon initial public offering	5,438		5,438
Repurchase of early exercised stock options (in shares)		(9,897)
Issuance of common stock net settlement of restricted stock units (in shares)		730,186
Issuance of common stock upon net settlement of restricted stock units	(10,273)		(10,273)
Issuance of common stock upon exercise of common stock warrants (in shares)		668,412
Vesting of common stock warrants	2,102		2,102
Share-based compensation expense	55,536		55,536
Change in other comprehensive income (loss)	(68)			(68)
Net loss	(68,554)				(68,554)
Balance at the end of the period (in shares) at Jun. 30, 2021		538,883,451
Balance at the end of the period at Jun. 30, 2021	$ 1,585,986	$ 54	1,920,936	(88)	(334,916)
Redeemable Convertible Preferred Stock Ending Balance (in shares) at Sep. 30, 2021	0
Redeemable Convertible Preferred Stock Ending Balance at Sep. 30, 2021	$ 0
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Issuance of common stock upon exercise of vested options (in shares)		153,374
Issuance of common stock upon exercise of vested options	401		401
Repurchase of early exercised stock options (in shares)		(37,621)
Issuance of common stock net settlement of restricted stock units (in shares)		574,211
Issuance of common stock upon net settlement of restricted stock units	(8,175)		(8,175)
Issuance of common stock upon exercise of common stock warrants (in shares)		203,610
Issuance of common stock upon exercise of common stock warrants	60		60
Vesting of common stock warrants	2,128		2,128
Share-based compensation expense	38,965		38,965
Change in other comprehensive income (loss)	(295)			(295)
Net loss	(45,730)				(45,730)
Balance at the end of the period (in shares) at Sep. 30, 2021		539,777,025
Balance at the end of the period at Sep. 30, 2021	$ 1,573,340	$ 54	$ 1,954,315	$ (383)	$ (380,646)

Condensed Consolidated Statem_4

Condensed Consolidated Statement of Redeemable Convertible Preferred Stock and Stockholders' Equity (Deficit) (Unaudited) - Parentheticals - USD ($) $ in Thousands	3 Months Ended	9 Months Ended
	Jun. 30, 2020	Sep. 30, 2021
Payments of stock issuance costs		$ 3,134
Redeemable Convertible Preferred Stock
Share price (in dollars per share)	$ 8.34	$ 8.34
Payments of stock issuance costs	$ 8,058	$ 8,058

Condensed Consolidated Statem_5

Condensed Consolidated Statements of Cash Flows (Unaudited) - USD ($) $ in Thousands	9 Months Ended
	Sep. 30, 2021	Sep. 30, 2020
Cash Flows From Operating Activities:
Net loss	$ (127,122)	$ (33,935)
Adjustments to reconcile net loss to net cash provided by operating activities:
Depreciation and amortization	2,567	2,608
Share-based compensation expense	105,893	18,620
Non-cash operating leases expense	1,579	1,519
Amortization of premium on marketable securities	974	231
Provision for doubtful accounts	108	44
Other	2,891	1,053
Changes in operating assets and liabilities:
Accounts receivable	974	(2,944)
Settlements receivable	(2,584)	137
Network incentives receivable	(20,002)	(3,426)
Prepaid expenses and other assets	(6,089)	(1,439)
Accounts payable	282	(314)
Revenue share payable	9,992	26,559
Accrued expenses and other liabilities	34,037	20,751
Operating lease liabilities	(2,147)	(890)
Net cash provided by operating activities	1,353	28,574
Cash flows from investing activities:
Purchases of property and equipment	(2,251)	(2,151)
Purchases of marketable securities	(375,089)	(183,367)
Sales of marketable securities	0	71,981
Maturities of marketable securities	114,688	72,190
Net cash used in investing activities	(262,652)	(41,347)
Cash flows from financing activities:
Proceeds from initial public offering, net of underwriters’ discounts and commissions	1,319,809	0
Proceeds from issuance of redeemable convertible preferred stock, net of issuance costs	0	166,942
Proceeds from exercise of stock options, including early exercised stock options	2,872	1,744
Proceeds from exercise of warrants	60	0
Taxes paid related to net share settlement of restricted stock units	(18,448)	0
Payment of deferred offering costs	(3,134)	(1,231)
Repurchase of early exercised unvested options	(73)	(66)
Net cash provided by financing activities	1,301,086	167,389
Net increase in cash, cash equivalents, and restricted cash	1,039,787	154,616
Cash, cash equivalents, and restricted cash- Beginning of period	228,233	68,144
Cash, cash equivalents, and restricted cash - End of period	$ 1,268,020	$ 222,760

Condensed Consolidated Statem_6

Condensed Consolidated Statements of Cash Flows (unaudited) - Reconciliation of Cash, Cash Equivalents and Restricted Cash and Supplemental Disclosure of Non-cash Investing and Financing Activities - USD ($) $ in Thousands	9 Months Ended
	Sep. 30, 2021	Sep. 30, 2020
Reconciliation of cash, cash equivalents, and restricted cash
Cash and cash equivalents	$ 1,260,220	$ 214,960
Restricted cash	7,800	7,800
Total cash, cash equivalents, and restricted cash	1,268,020	222,760
Supplemental disclosures of non-cash investing and financing activities:
Purchase of property and equipment accrued and not yet paid	1,193	99
Deferred offering costs not yet paid	0	647
Conversion of redeemable convertible preferred stock to common stock	$ 0	$ 809

Business Overview and Basis of

Business Overview and Basis of Presentation	9 Months Ended
	Sep. 30, 2021
Accounting Policies [Abstract]
Business Overview and Basis of Presentation	Business Overview and Basis of Presentation Marqeta, Inc., or the Company, creates digital payment technology for innovation leaders. The Company's modern card issuing platform, or the Platform, places control over payment transactions into the hands of its customers, or Customers, enabling them to develop modern state-of-the-art product experiences. The Company provides all of its Customers issuer processor services and for most of its Customers it also acts as a card program manager. The Company primarily earns revenue from processing card transactions for its Customers. The Company was incorporated in the state of Delaware in 2010 and is headquartered in Oakland, California, with offices in the United States and United Kingdom, and a presence in Australia. Initial Public Offering In June 2021, the Company completed an initial public offering, or the IPO, in which the Company issued and sold 52,272,727 shares of its newly authorized Class A common stock, which included 6,818,181 shares that were offered and sold pursuant to the full exercise of the underwriters’ option to purchase additional shares at a price of $27.00 per share. The Company received aggregate net proceeds of $1.3 billion after deducting underwriting discounts and commissions of $91.6 million and offering costs of $7.5 million. Immediately prior to the completion of the IPO, the Company filed its Amended and Restated Certificate of Incorporation authorizing a total of 1,500,000,000 shares of Class A common stock which entitles holders to one vote per share, 600,000,000 shares of Class B common stock which entitles holders to 10 votes per share, and 100,000,000 shares of undesignated preferred stock. All shares of common stock then outstanding were reclassified as Class B common stock and all redeemable convertible preferred stock then outstanding were converted into 351,844,340 shares of common stock on a one-for-one basis and reclassified into Class B common stock. In addition, 2,569,528 shares of common stock warrants were converted to an equivalent number of shares of Class B common stock warrants and 203,610 shares of convertible preferred stock warrants were converted to an equivalent number of shares of Class B common stock warrants. Basis of Presentation The accompanying unaudited condensed consolidated financial statements have been prepared in accordance with generally accepted accounting principles in the United States of America, or GAAP, and the applicable rules and regulations of the Securities and Exchange Commission, or the SEC, for interim reporting. Certain information and note disclosures included in our annual financial statements prepared in accordance with GAAP have been condensed or omitted pursuant to such rules and regulations. The condensed consolidated balance sheet as of December 31, 2020 has been derived from our audited consolidated financial statements, which are included in the prospectus dated June 8, 2021, as filed with the SEC pursuant to Rule 424(b) under the Securities Act of 1933, or the Prospectus. The accompanying condensed consolidated financial statements should be read in conjunction with our consolidated financial statements and notes thereto included in the Prospectus. The accompanying unaudited condensed consolidated financial statements include the accounts of the Company and its wholly owned subsidiaries. All intercompany balances and transactions have been eliminated in consolidation. In the opinion of management, the accompanying condensed consolidated financial statements reflect all adjustments of a normal recurring nature considered necessary for a fair presentation of the Company's consolidated financial position, results of operations, comprehensive loss, and cash flows for the interim periods presented. The interim results for the three and nine months ended September 30, 2021 are not necessarily indicative of the results that may be expected for the year ending December 31, 2021, or for any other future annual or interim period. Use of Estimates The preparation of the financial statements requires management to make estimates and assumptions relating to reported amounts of assets and liabilities, disclosure of contingent assets and liabilities, and reported amounts of revenue and expenses. Significant estimates and assumptions relate to the estimation of variable consideration in contracts with Customers, collectability of accounts receivable, reserve for contract contingencies and processing errors, the useful lives of property and equipment, the incremental borrowing rate used to determine operating lease liabilities, the fair value of equity awards and warrants, and share-based compensation. Actual results could differ materially from these estimates. Business Risks and Uncertainties The Company has incurred net losses since its inception. For the three and nine months ended September 30, 2021, the Company incurred net losses of $45.7 million and $127.1 million, respectively, and had an accumulated deficit of $380.6 million as of September 30, 2021. The Company expects losses from operations to continue for the foreseeable future as it incurs costs and expenses related to creating new products for Customers, acquiring new Customers, developing its brand, expanding into new geographies and developing the existing Platform infrastructure. The Company believes that its cash and cash equivalents of $1.3 billion and marketable securities of $409.0 million as of September 30, 2021 are sufficient to fund its operations through at least the next twelve months from the issuance of these financial statements. In March 2020, the World Health Organization declared the outbreak of a novel coronavirus (COVID-19) as a pandemic. Since then, the COVID-19 pandemic has continued to spread throughout the United States and the world. While the Company has not been adversely affected by the COVID-19 pandemic to date, the prolonged disruption to the economy and the long-term financial impact of the pandemic cannot be reasonably estimated. The Company continues to monitor the situation and may take actions that alter its operations and business practices as may be required by federal, state, or local authorities or that the Company determines are in the best interests of its Customers, vendors, and employees.

Summary of Significant Accounti

Summary of Significant Accounting Policies	9 Months Ended
	Sep. 30, 2021
Accounting Policies [Abstract]
Summary of Significant Accounting Policies	Summary of Significant Accounting Policies The Company’s significant accounting policies are discussed in “Consolidated Financial Statements — Note 2. Summary of Significant Accounting Policies” in the Prospectus. There have been no significant changes to these policies during the three and nine months ended September 30, 2021. Segment Information The Company operates as a single operating segment. The Company's chief operating decision maker is its Chief Executive Officer, who reviews financial information presented on a consolidated basis for purposes of making operating decisions, assessing financial performance, allocating resources and evaluating the Company's financial performance. For the three and nine months ended September 30, 2021 and 2020, revenue outside of the United States, based on the billing address of the Customer, was not material. As of September 30, 2021 and December 31, 2020, long-lived assets located outside of the United States were not material. Restricted Cash Restricted cash consists of deposits with financial institutions that issue payment cards (credit, debit, or prepaid) either on their own behalf or on behalf of businesses that issue customized card products to their end users, or Issuing Banks, to provide the Issuing Bank collateral in the event that Customers’ funds are not deposited at the Issuing Banks in time to settle Customers’ transactions with the networks that provide the infrastructure for settlement and card payment information flows, or Card Networks. Restricted cash also includes cash used to secure a letter of credit for the Company’s lease of its office headquarters in Oakland, California. Deferred Offering Costs Deferred offering costs consist primarily of accounting, legal, and other fees related to the IPO. Upon the completion of the IPO in June 2021, the deferred offering costs were reclassified to stockholders’ equity and recorded net against the proceeds from the IPO. New Accounting Standards Adopted In August 2018, the Financial Accounting Standards Board, or the FASB, issued Accounting Standards Update, or ASU, No. 2018-15, Intangibles—Goodwill and Other— Internal-Use Software (Subtopic 350-40), which aligns the requirements for capitalizing implementation costs incurred in a hosting arrangement that is a service contract with the requirements for capitalizing implementation costs incurred to develop or obtain internal-use software (and hosting arrangements that include an internal use software license). The accounting for the service element of a hosting arrangement that is a service contract is not affected by the amendments in this ASU. The Company adopted the new standard 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. New Accounting Standards Not Yet Adopted As an emerging growth company, the Jumpstart Our Business Startups Act, or the JOBS Act, allows the Company to delay adoption of new or revised accounting pronouncements applicable to public companies until such pronouncements are made applicable to private companies. The Company has elected to use this extended transition period under the JOBS Act. The adoption date discussed below reflects this election. In June 2016, the FASB issued ASU No. 2016-13, Financial instruments – Credit Losses (Topic 326): Measurement of Credit Losses on Financial Instruments . ASU 2016-13 replaces the incurred loss model with the current expected credit loss, or CECL, model to estimate credit losses for financial assets measured at amortized cost and certain off-balance sheet credit exposures. It also eliminates the concept of other-than-temporary impairment and requires credit losses related to available-for-sale debt securities to be recorded through an allowance for credit losses rather than as a reduction in the amortized cost basis of the securities. The CECL model requires a company to estimate credit losses expected over the life of the financial assets based on historical experience, current conditions and reasonable and supportable forecasts. The guidance will be effective for the Company beginning January 1, 2023, and interim periods therein. The amendment requires a modified retrospective approach by recording a cumulative-effect adjustment to retained earnings as of the beginning of the period of adoption. Early adoption is permitted. The Company is still evaluating the impact this ASU will have on its condensed consolidated financial statements.

Revenue

Revenue	9 Months Ended
	Sep. 30, 2021
Revenue from Contract with Customer [Abstract]
Revenue	Revenue Disaggregation of Revenue The following table provides information about disaggregated revenue from Customers: Three Months Ended September 30, Nine Months Ended September 30, 2021 2020 2021 2020 Platform services revenue, net $ 126,388 $ 81,620 $ 350,884 $ 195,260 Other services revenue 5,124 2,686 10,877 6,836 Total net revenue $ 131,512 $ 84,306 $ 361,761 $ 202,096 Contract Balances The following table provides information about contract assets and deferred revenue: Contract balance Balance sheet line reference September 30, December 31, Contract assets - current Prepaid expenses and other current assets $ 672 $ 118 Contract assets - non-current Other assets 830 294 Total contract assets $ 1,502 $ 412 Deferred revenue - current Accrued expenses and other current liabilities $ 8,978 $ 3,983 Deferred revenue - non-current Other liabilities 6,882 8,865 Total deferred revenue $ 15,860 $ 12,848 Net revenue recognized during the three months ended September 30, 2021 and 2020 that was included in the deferred revenue balances at the beginning of the respective periods was $3.3 million and $1.0 million, respectively. Net revenue recognized during the nine months ended September 30, 2021 and 2020 that was included in the deferred revenue balances at the beginning of the respective periods was $2.9 million and $0.6 million, respectively. Remaining Performance Obligations The Company has performance obligations associated with commitments in Customer contracts for future stand-ready obligations to process transactions throughout the contractual term. Remaining performance obligations include related deferred revenue currently recorded and exclude contracts for which the Company recognizes revenue at the amount to which it has the right to invoice for services as performed. The amount and timing of revenue recognition is largely driven by the Customer’s utilization of the Company’s Platform services.

Marketable Securities

Marketable Securities	9 Months Ended
	Sep. 30, 2021
Investments [Abstract]
Marketable Securities	Marketable Securities The amortized cost, unrealized gain (loss), and estimated fair value of the Company's investments in securities available for sale consisted of the following: September 30, 2021 Amortized Cost Unrealized Gain Unrealized Loss Estimated Fair Value Marketable securities U.S. government securities $ 374,849 $ 1 $ (257) $ 374,593 Commercial paper 16,880 — — 16,880 Asset-backed securities 2,017 — — 2,017 Corporate debt securities 15,468 3 (7) 15,464 Total marketable securities $ 409,214 $ 4 $ (264) $ 408,954 December 31, 2020 Amortized Cost Unrealized Gain Unrealized Loss Estimated Fair Value Marketable securities U.S. government securities $ 125,823 $ 47 $ (6) $ 125,864 Commercial paper 4,991 — — 4,991 Asset-backed securities 4,294 21 — 4,315 Corporate debt securities 14,683 52 (2) 14,733 Total marketable securities $ 149,791 $ 120 $ (8) $ 149,903 The Company had sixteen and six separate marketable securities in unrealized loss positions as of September 30, 2021 and December 31, 2020, respectively. The Company did not identify any marketable securities that were other-than-temporarily impaired as of September 30, 2021 and December 31, 2020. The following table summarizes the stated maturities of the Company’s marketable securities: September 30, 2021 December 31, 2020 Amortized Cost Estimated Fair Value Amortized Cost Estimated Fair Value Due within one year $ 56,756 $ 56,756 $ 149,791 $ 149,903 Due after one year through two years 352,458 352,198 — — Total $ 409,214 $ 408,954 $ 149,791 $ 149,903

Fair Value Measurements

Fair Value Measurements	9 Months Ended
	Sep. 30, 2021
Fair Value Disclosures [Abstract]
Fair Value Measurements	Fair Value Measurements The Company’s financial instruments consist of cash equivalents, marketable securities, accounts receivable, unbilled Customers' receivable, settlements receivable, accounts payable, accrued liabilities, and prior to the IPO, redeemable convertible preferred stock warrant liabilities. Cash equivalents are stated at amortized cost, which approximates fair value at the balance sheet dates, due to the short period of time to maturity. Marketable securities are carried at fair value. Accounts receivable, unbilled Customers' receivable, settlements receivable, accounts payable, and accrued liabilities are stated at their carrying value, which approximates fair value due to the short time to the expected receipt or payment date. The redeemable convertible preferred stock warrant liabilities were carried at fair value. The following tables present the fair value hierarchy for assets and liabilities measured at fair value: September 30, 2021 Level 1 Level 2 Level 3 Total Fair Value Cash equivalents Money market funds $ 1,227,637 $ — $ — $ 1,227,637 Marketable securities U.S. government securities 374,593 — — 374,593 Commercial paper — 16,880 — 16,880 Asset-backed securities — 2,017 — 2,017 Corporate debt securities — 15,464 — 15,464 Total assets $ 1,602,230 $ 34,361 $ — $ 1,636,591 December 31, 2020 Level 1 Level 2 Level 3 Total Fair Value Cash equivalents Money market funds $ 203,592 $ — $ — $ 203,592 Marketable securities U.S. government securities 125,864 — — 125,864 Commercial paper — 4,991 — 4,991 Asset-backed securities — 4,315 — 4,315 Corporate debt securities — 14,733 — 14,733 Total assets $ 329,456 $ 24,039 $ — $ 353,495 Other liabilities Redeemable convertible preferred stock warrants $ — $ — $ 2,517 $ 2,517 Total liabilities $ — $ — $ 2,517 $ 2,517 The Company classifies money market funds, commercial paper, U.S. government securities, asset-backed securities and corporate securities within Level 1 or Level 2 of the fair value hierarchy because the Company values these investments using quoted market prices or alternative pricing sources and models utilizing market observable inputs. The Company classifies the redeemable convertible preferred stock warrants within Level 3 because the Company determines their fair value using unobservable inputs, including the fair value of the Company’s redeemable Series B convertible stock, which the Company determines in the same manner as the fair value of its common stock prior to the IPO. The Company records the change in the fair value of redeemable convertible preferred stock warrants in other income (expense), net in the condensed consolidated statements of operations. Immediately prior to the completion of the IPO in June 2021, the outstanding redeemable convertible preferred stock warrants were converted to Class B common stock warrants and the fair value of the liability as of that date was reclassified into the Company’s Class B common stock and additional paid-in capital. The fair value of the redeemable convertible preferred stock warrant liabilities was estimated using the following assumptions: June 9, December 31, Dividend yield 0.00% 0.00% Expected volatility 49.93% 49.93% Expected term (in years) 2.34 2.78 Risk-free interest rate 0.31% 0.17% Fair value of Series B redeemable convertible preferred stock $27.00 $12.66 The following table sets forth a summary of the changes in the fair value of the redeemable convertible preferred stock warrant liabilities: September 30, December 31, Balance, beginning of the period $ 2,517 $ 569 Remeasurement of redeemable convertible preferred stock warrant liabilities 2,921 1,948 Reclassification of redeemable convertible preferred stock warrant liabilities to common stock and additional paid-in capital upon initial public offering (5,438) — Balance, end of the period $ — $ 2,517 There were no transfers of financial instruments between the fair value hierarchy levels during the three and nine months ended September 30, 2021 and the year ended December 31, 2020.

Certain Balance Sheet Component

Certain Balance Sheet Components	9 Months Ended
	Sep. 30, 2021
Organization, Consolidation and Presentation of Financial Statements [Abstract]
Certain Balance Sheet Components	Certain Balance Sheet Components Prepaid Expenses and Other Current Assets Prepaid expenses and other current assets consisted of the following: September 30, December 31, Prepaid expenses $ 12,210 $ 6,162 Card program deposits 2,167 2,174 Other current assets 5,482 3,125 Prepaid expenses and other current assets $ 19,859 $ 11,461 Property and Equipment, net Property and equipment consisted of the following: September 30, December 31, Leasehold improvements $ 8,110 8,110 Computer equipment 8,917 7,634 Furniture and fixtures 2,459 2,333 Internally developed and purchased software 2,905 1,299 22,391 19,376 Accumulated depreciation and amortization (12,200) (9,899) Property and equipment, net $ 10,191 $ 9,477 Depreciation and amortization expense was $0.8 million and $0.9 million for the three months ended September 30, 2021 and 2020, respectively, and $2.6 million and $2.6 million for the nine months ended September 30, 2021 and 2020, respectively. The Company capitalized $0.1 million and $1.5 million as internal-use software costs during the three and nine months ended September 30, 2021, respectively. The Company did not capitalize any internal-use software costs during the three and nine months ended September 30, 2020, because development costs meeting capitalization criteria were not material during the respective periods. Accrued Expenses and Other Current Liabilities Accrued expenses and other current liabilities consisted of the following: September 30, December 31, Accrued costs of revenue $ 34,086 $ 24,529 Reserve for contract contingencies and processing errors 11,686 9,537 Accrued compensation and benefits 25,568 14,078 Deferred revenue 8,978 3,983 Operating lease liabilities, current portion 2,935 2,771 Accrued professional services 2,552 867 Other accrued liabilities 11,801 4,780 Accrued expenses and other current liabilities $ 97,606 $ 60,545 Other Liabilities Other liabilities consisted of the following: September 30, December 31, Deferred revenue, net of current portion $ 6,882 $ 8,865 Other long-term liabilities 1,196 1,587 Other liabilities $ 8,078 $ 10,452

Commitments and Contingencies

Commitments and Contingencies	9 Months Ended
	Sep. 30, 2021
Commitments and Contingencies Disclosure [Abstract]
Commitments and Contingencies	Commitments and Contingencies Operating Leases In 2016, the Company entered into a lease agreement for its corporate headquarters in Oakland, California for 19,000 square feet of office space, which was subsequently amended resulting in a total of 63,000 square feet of office space being leased. The non-cancellable operating lease expires in February 2026 and includes options to extend the lease term, generally at the then-market rates. The Company excludes extension options that are not reasonably certain to be exercised from its lease terms. The Company’s lease payments consist primarily of fixed rental payments for the right to use the underlying leased assets over the lease terms. The Company is responsible for operating expenses that exceed the amount of base operating expenses as defined in the original lease agreement. The Company's operating lease costs are as follows: Three Months Ended September 30, Nine Months Ended September 30, 2021 2020 2021 2020 Operating lease cost $ 843 $ 877 $ 2,581 $ 2,645 Variable lease cost 65 112 135 336 Short-term lease cost 237 71 368 206 Total lease cost $ 1,145 $ 1,060 $ 3,084 $ 3,187 The Company does not have any sublease income and the Company’s lease agreements do not contain any residual value guarantees or material restrictive covenants. The weighted average remaining operating lease term and the weighted average discount rate used in the calculation of the Company's lease assets and lease liabilities were as follows: September 30, December 31, Weighted average remaining operating lease term (in years) 4.3 5.1 Weighted average discount rate 7.7% 7.7% Maturities of operating lease liabilities by year are as follows as of September 30, 2021: Remainder of 2021 $ 1,012 2022 4,112 2023 4,239 2024 4,472 2025 4,599 Thereafter 780 Total lease payments 19,214 Less imputed interest (3,061) Total operating lease liabilities $ 16,153 Supplemental cash flow information related to the Company's operating leases was as follows: Three Months Ended September 30, Nine Months Ended September 30, 2021 2020 2021 2020 Cash paid for operating lease liabilities $ 1,007 $ 900 $ 3,072 $ 2,699 Operating lease right-of-use assets obtained in exchange for new operating lease liabilities $ — $ — $ — $ 192 Letters of Credit In connection with the lease for its corporate headquarters office space, the Company is required to provide the landlord a letter of credit in the amount of $1.5 million. The Company has secured this letter of credit by depositing $1.5 million with the issuing financial institution, which deposit is classified as restricted cash in the condensed consolidated balance sheets. Purchase Obligations As of September 30, 2021, the Company had non-cancellable purchase commitments with certain service providers and Issuing Banks of $9.1 million, payable over the next 5 years. These purchase obligations generally represent minimum commitments for cloud-computing services and issuing bank processing fees over the fixed, non-cancellable respective contract terms. Defined Contribution Plans The Company maintains defined contribution plans for eligible employees, including a 401(k) plan that covers substantially all of its U.S. based employees and to which the Company provides a matching contribution of 50% of the first 6% of compensation that an employee contributes. The matching contribution vests after one year of service. During the three months ended September 30, 2021 and 2020, the Company contributed a total of $0.8 million and $0.5 million to its defined contribution plans, respectively. During the nine months ended September 30, 2021 and 2020, the Company contributed a total of $2.2 million and $1.4 million to its defined contribution plans, respectively. Legal Contingencies From time to time in the normal course of business, the Company may be subject to various legal matters such as threatened or pending claims or proceedings. As of September 30, 2021 and December 31, 2020, there were no legal contingency matters, either individually or in aggregate, that would have a material adverse effect on the Company’s financial position, results of operations, or cash flows. Given the unpredictable nature of legal proceedings, the Company bases its assessment on the information available at the time. As additional information becomes available, the Company reassesses the potential liability and may revise the estimate. Settlement of Payment Transactions Generally, Customers deposit a certain amount of pre-funding into accounts maintained at Issuing Banks to settle their payment transactions. Such pre-funding amounts may only be used to settle Customers’ payment transactions and are not considered assets of the Company. As such, the funds held in Customers’ accounts at Issuing Banks are not reflected on the Company’s condensed consolidated balance sheets. If a Customer does not have sufficient funds to settle a transaction, the Company is liable to the Issuing Bank to settle the transaction and would therefore incur losses if such amounts cannot be subsequently recovered from the Customer. Indemnifications In the ordinary course of business, the Company enters into agreements of varying scope and terms pursuant to which it agrees to indemnify vendors, lessors, business partners, and other parties with respect to certain matters, including, but not limited to, losses arising out of the 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 its 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. No demands have been made upon the Company to provide indemnification under such agreements and there are no claims that the Company is aware of that could have a material effect on its condensed consolidated balance sheets, condensed consolidated statements of operations, condensed consolidated statements of comprehensive loss, or condensed consolidated statements of cash flows. The Company also includes service level commitments to its Customers warranting certain levels of performance and permitting those Customers to receive credits in the event the Company fails to meet those levels. Non-income Taxes The Company is subject to state and local indirect taxes in various jurisdictions in the United States. In several of these jurisdictions the Company has reviewed and concluded that such indirect taxes are not applicable to the Company’s service offerings. In a few of these jurisdictions the tax regulations are less clear. While the Company believes its service offerings are not subject to tax in these jurisdictions, the Company is working with the respective state and local tax authorities to confirm the Company’s conclusions. The Company has not recorded a liability associated with these matters as of September 30, 2021 as it believes it is not probable that the indirect taxes are applicable to the Company. In the event that adverse information is received in response to the Company's state inquiries, and the Company chooses not to appeal, a potential tax liability would be $6.0 million as of September 30, 2021.
Commitments and Contingencies	Commitments and Contingencies Operating Leases In 2016, the Company entered into a lease agreement for its corporate headquarters in Oakland, California for 19,000 square feet of office space, which was subsequently amended resulting in a total of 63,000 square feet of office space being leased. The non-cancellable operating lease expires in February 2026 and includes options to extend the lease term, generally at the then-market rates. The Company excludes extension options that are not reasonably certain to be exercised from its lease terms. The Company’s lease payments consist primarily of fixed rental payments for the right to use the underlying leased assets over the lease terms. The Company is responsible for operating expenses that exceed the amount of base operating expenses as defined in the original lease agreement. The Company's operating lease costs are as follows: Three Months Ended September 30, Nine Months Ended September 30, 2021 2020 2021 2020 Operating lease cost $ 843 $ 877 $ 2,581 $ 2,645 Variable lease cost 65 112 135 336 Short-term lease cost 237 71 368 206 Total lease cost $ 1,145 $ 1,060 $ 3,084 $ 3,187 The Company does not have any sublease income and the Company’s lease agreements do not contain any residual value guarantees or material restrictive covenants. The weighted average remaining operating lease term and the weighted average discount rate used in the calculation of the Company's lease assets and lease liabilities were as follows: September 30, December 31, Weighted average remaining operating lease term (in years) 4.3 5.1 Weighted average discount rate 7.7% 7.7% Maturities of operating lease liabilities by year are as follows as of September 30, 2021: Remainder of 2021 $ 1,012 2022 4,112 2023 4,239 2024 4,472 2025 4,599 Thereafter 780 Total lease payments 19,214 Less imputed interest (3,061) Total operating lease liabilities $ 16,153 Supplemental cash flow information related to the Company's operating leases was as follows: Three Months Ended September 30, Nine Months Ended September 30, 2021 2020 2021 2020 Cash paid for operating lease liabilities $ 1,007 $ 900 $ 3,072 $ 2,699 Operating lease right-of-use assets obtained in exchange for new operating lease liabilities $ — $ — $ — $ 192 Letters of Credit In connection with the lease for its corporate headquarters office space, the Company is required to provide the landlord a letter of credit in the amount of $1.5 million. The Company has secured this letter of credit by depositing $1.5 million with the issuing financial institution, which deposit is classified as restricted cash in the condensed consolidated balance sheets. Purchase Obligations As of September 30, 2021, the Company had non-cancellable purchase commitments with certain service providers and Issuing Banks of $9.1 million, payable over the next 5 years. These purchase obligations generally represent minimum commitments for cloud-computing services and issuing bank processing fees over the fixed, non-cancellable respective contract terms. Defined Contribution Plans The Company maintains defined contribution plans for eligible employees, including a 401(k) plan that covers substantially all of its U.S. based employees and to which the Company provides a matching contribution of 50% of the first 6% of compensation that an employee contributes. The matching contribution vests after one year of service. During the three months ended September 30, 2021 and 2020, the Company contributed a total of $0.8 million and $0.5 million to its defined contribution plans, respectively. During the nine months ended September 30, 2021 and 2020, the Company contributed a total of $2.2 million and $1.4 million to its defined contribution plans, respectively. Legal Contingencies From time to time in the normal course of business, the Company may be subject to various legal matters such as threatened or pending claims or proceedings. As of September 30, 2021 and December 31, 2020, there were no legal contingency matters, either individually or in aggregate, that would have a material adverse effect on the Company’s financial position, results of operations, or cash flows. Given the unpredictable nature of legal proceedings, the Company bases its assessment on the information available at the time. As additional information becomes available, the Company reassesses the potential liability and may revise the estimate. Settlement of Payment Transactions Generally, Customers deposit a certain amount of pre-funding into accounts maintained at Issuing Banks to settle their payment transactions. Such pre-funding amounts may only be used to settle Customers’ payment transactions and are not considered assets of the Company. As such, the funds held in Customers’ accounts at Issuing Banks are not reflected on the Company’s condensed consolidated balance sheets. If a Customer does not have sufficient funds to settle a transaction, the Company is liable to the Issuing Bank to settle the transaction and would therefore incur losses if such amounts cannot be subsequently recovered from the Customer. Indemnifications In the ordinary course of business, the Company enters into agreements of varying scope and terms pursuant to which it agrees to indemnify vendors, lessors, business partners, and other parties with respect to certain matters, including, but not limited to, losses arising out of the 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 its 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. No demands have been made upon the Company to provide indemnification under such agreements and there are no claims that the Company is aware of that could have a material effect on its condensed consolidated balance sheets, condensed consolidated statements of operations, condensed consolidated statements of comprehensive loss, or condensed consolidated statements of cash flows. The Company also includes service level commitments to its Customers warranting certain levels of performance and permitting those Customers to receive credits in the event the Company fails to meet those levels. Non-income Taxes The Company is subject to state and local indirect taxes in various jurisdictions in the United States. In several of these jurisdictions the Company has reviewed and concluded that such indirect taxes are not applicable to the Company’s service offerings. In a few of these jurisdictions the tax regulations are less clear. While the Company believes its service offerings are not subject to tax in these jurisdictions, the Company is working with the respective state and local tax authorities to confirm the Company’s conclusions. The Company has not recorded a liability associated with these matters as of September 30, 2021 as it believes it is not probable that the indirect taxes are applicable to the Company. In the event that adverse information is received in response to the Company's state inquiries, and the Company chooses not to appeal, a potential tax liability would be $6.0 million as of September 30, 2021.

Stock Incentive Plans

Stock Incentive Plans	9 Months Ended
	Sep. 30, 2021
Share-based Payment Arrangement [Abstract]
Stock Incentive Plans	Stock Incentive Plans The following table summarizes the share-based compensation expense recognized for the different stock incentive plans discussed below: Three Months Ended September 30, Nine Months Ended September 30, 2021 2020 2021 2020 Stock options (1) $ 22,180 $ 2,907 $ 47,322 $ 8,134 Secondary sales of common stock — 9,050 11,642 10,486 Restricted stock units 15,882 — 45,948 — Employee Stock Purchase Plan 903 — 981 — Total $ 38,965 $ 11,957 $ 105,893 $ 18,620 (1) Includes the share-based compensation expense recognized for employees, non-employees and the CEO Long-Term Performance Award. During the three and nine months ended September 30, 2021, share-based compensation expense recognized for the CEO Long-Term Performance Award was $13.4 million and $24.8 million, respectively. 2011 Equity Incentive Plan In 2011, the Company’s board of directors adopted, and its stockholders approved, the 2011 Equity Incentive Plan, which was most recently amended and restated in 2021 as the Amended and Restated 2011 Equity Incentive Plan, or the 2011 Plan. The 2011 Plan provided for the grant of share-based awards to employees, non-employee directors, and other service providers of the Company. The 2011 Plan was terminated in June 2021 in connection with the IPO, but continues to govern the terms of outstanding awards that were granted prior to the IPO. No further equity awards will be granted under the 2011 Plan. Upon the expiration, forfeiture, cancellation, hold back upon exercise or settlement of an award to satisfy the exercise price or tax withholding, or repurchase of any shares of Class B common stock underlying outstanding share-based awards granted under the 2011 Plan, an equal number of shares of Class A common stock will become available for grant under the 2021 Stock Option and Incentive Plan, or the 2021 Plan, that was established in connection with the IPO. 2021 Stock Option and Incentive Plan In May 2021, the Company’s board of directors adopted, and its stockholders approved, the 2021 Plan, which became effective in connection with the IPO. The 2021 Plan provides for the grant of incentive stock options, nonqualified stock options, stock appreciation rights, restricted stock awards, restricted stock units, or RSUs, and other forms of equity and cash compensation. A total of 60,000,000 shares of the Company’s Class A common stock were initially reserved for issuance under the 2021 Plan. The number of shares of Class A common stock reserved and available for issuance under the 2021 Plan will automatically increase each January 1, beginning on January 1, 2022, by 5% of the number of shares of the Company’s Class A and Class B common stock outstanding on the immediately preceding December 31, or such lesser number of shares as determined by the Company’s compensation committee of the Company’s board of directors. 2021 Employee Stock Purchase Plan In May 2021, the Company’s board of directors adopted, and its stockholders approved, the 2021 Employee Stock Purchase Plan, or the ESPP, which became effective in connection with the IPO. The ESPP authorizes the issuance of shares of the Company’s Class A common stock pursuant to purchase rights granted to employees. A total of 6,000,000 shares of the Company’s Class A common stock were initially reserved for issuance under the ESPP. The ESPP provides that the number of shares reserved and available for issuance will automatically increase each January 1, beginning on January 1, 2022, by the lesser of 12,000,000 shares of the Company’s Class A common stock, 1% of the number of shares of the Company’s Class A and Class B common stock outstanding on the immediately preceding December 31, or such lesser number of shares as determined by the Company’s compensation committee. The offering periods of the ESPP are six months long and begin on May 16 and November 16 of each year, except for the initial offering period. The initial offering period began on June 8, 2021 and will end on the last business day occurring on or before November 15, 2021. The price at which Class A common stock is purchased under the ESPP is equal to 85% of the fair market value of a share of the Company’s Class A common stock on the first or last day of the offering period, whichever is lower. Stock Options Under the 2011 Plan and the 2021 Plan, the exercise price of an incentive stock option shall not be less than the fair market value of one share of the Company’s Class A common stock on the date of grant (not less than 110% of the fair market value of one share of Class A common stock for grants to stockholders owning more than 10% of the total combined voting power of all classes of stock of the Company, or a 10% Stockholder. Options are exercisable over periods not to exceed ten years from the date of grant (five years for incentive stock options granted to 10% Stockholders). A summary of the Company's stock option activity under both stock incentive plans was as follows: Number of Options Weighted-Average Exercise Price per Share Weighted-Average Remaining Contractual Life Aggregate Intrinsic Value (1) Balance as of December 31, 2020 (2) 23,421,374 $ 1.35 8.33 years $ 248,002 Granted 29,113,555 20.07 Exercised (3,236,786) 1.06 Canceled and forfeited (3,241,591) 2.89 Balance as of September 30, 2021 (2) 46,056,552 $ 13.09 8.66 years $ 417,075 Vested as of September 30, 2021 9,922,355 $ 1.43 6.73 years $ 219,482 (1) Intrinsic value is calculated based on the difference between the exercise price of in-the-money-stock options and the fair value of the common stock as of the respective balance sheet dates. (2) The 2011 Plan allows for early exercise of stock options and these balances include all exercisable stock options regardless of vesting status. As of September 30, 2021, unrecognized compensation costs related to unvested outstanding stock options, excluding the CEO Long-Term Performance Award, was $105.8 million. These costs are expected to be recognized over a period of 2.7 years. The fair value of stock options granted was estimated using the Black-Scholes option pricing model and the following weighted average assumptions: Three Months Ended September 30, Nine Months Ended September 30, 2021 2020 2021 2020 Dividend yield 0.0% 0.0% 0.0% 0.0% Expected volatility 57.48% 49.93% 54.15% 48.11% Expected term (in years) 6.08 6.02 6.73 6.02 Risk-free interest rate 1.18% 0.36% 1.22% 0.54% Subsequent to the completion of the IPO, the fair value of the Company’s common stock is determined by the closing price, on the date of grant, of its Class A common stock, which is traded on the Nasdaq Global Select Market. Secondary Sales of Common Stock Prior to the completion of the IPO, certain economic interest holders acquired outstanding common stock from current or former employees for a purchase price greater than the Company's estimated fair value at the time of the transactions. During the three months ended September 30, 2021, the Company did not record any share-based compensation expense related to secondary sales of common stock. During the three months ended September 30, 2020, the Company recorded share-based compensation expense for the difference between the price paid and the estimated fair value on the date of the transaction of $9.0 million. During the nine months ended September 30, 2021 and 2020, the Company recorded share-based compensation expense for the difference between the price paid and the estimated fair value on the date of the transaction of $11.6 million and $10.5 million, respectively. CEO Long-Term Performance Award In April and May 2021, the Company’s board of directors granted the Company’s Chief Executive Officer equity incentive awards in the form of performance-based stock options covering 19,740,923 and 47,267 shares of our Class B common stock with an exercise price of $21.49 and $23.40 per share, respectively, or collectively, the CEO Long-Term Performance Award. The CEO Long-Term Performance Award vests upon the satisfaction of a service condition and the achievement of certain stock price hurdles over a seven year performance period following the expiration of the lock-up period associated with the IPO. The stock price hurdle will be achieved if the average closing price of a share of our Class A common stock during any 90 consecutive trading day period during the performance period equals or exceeds the Company stock price hurdle set forth in the table below. The CEO Long-Term Performance Award is divided into seven equal tranches which vest upon the achievement of the following Company stock price hurdles: Tranche Company Stock Price Hurdle Number of Options Eligible to Vest 1 $67.50 2,826,884 2 $78.98 2,826,884 3 $92.40 2,826,884 4 $108.11 2,826,884 5 $126.49 2,826,884 6 $147.99 2,826,884 7 $173.15 2,826,884 Total 19,788,188 The grant date fair value of the CEO Long-Term Performance Award was estimated using a Monte Carlo simulation model that incorporated multiple stock price paths and probabilities that the Company stock price hurdles are met. The weighted-average grant date fair value of the seven tranches of the CEO Long-Term Performance Award was estimated to be $10.53 per option share. As of September 30, 2021, the aggregate unrecognized compensation cost of the CEO Long-Term Performance Award was $183.6 million, which is expected to be recognized over the remaining derived service period of 4.3 years. Restricted Stock Units Commencing in 2020, the Company began granting RSUs to employees. RSUs granted prior to April 1, 2021 vest upon the satisfaction of both a service condition and a liquidity condition. The service condition for these awards is satisfied over four years. On June 8, 2021, the Company completed its IPO and the liquidity condition for these awards was satisfied and the Company recognized $23.1 million of share-based compensation expense associated with RSUs that had service-vested as of the IPO completion date. Subsequent to the IPO, the unamortized grant date fair value of these RSUs will be recorded as share-based compensation expense over the remaining service period. RSUs granted on or after April 1, 2021, vest upon the satisfaction of a service condition. The service condition for these awards is satisfied over four years. In the three months ended September 30, 2021, the Company recognized $15.9 million of share-based compensation expense related to these RSUs. A summary of the Company's RSUs activity under both stock incentive plans was as follows: Number of Restricted Stock Units Weighted-average grant date fair value per share Balance as of December 31, 2020 4,430,336 $ 4.93 Granted 7,420,972 20.58 Vested (1,985,645) 7.60 Canceled and forfeited (649,478) 11.78 Balance as of September 30, 2021 9,216,185 $ 15.85 During the three and nine months ended September 30, 2021, share-based compensation expense recognized for RSUs was $15.9 million and $45.9 million, respectively. As of September 30, 2021, unrecognized compensation costs related to unvested RSUs was $136.4 million. These costs are expected to be recognized over a period of 3.2 years.

Warrants to Purchase Common Sto

Warrants to Purchase Common Stock	9 Months Ended
	Sep. 30, 2021
Equity [Abstract]
Warrants to Purchase Common Stock	Warrants to Purchase Common Stock In both 2013 and 2014, in connection with prior loan agreements, the Company issued two warrants to the lender to purchase 101,805 and 101,805 shares of Series B redeemable convertible preferred stock, both at an exercise price of $0.295 per share. As of September 30, 2021, both warrants are fully vested and exercisable and expire in 2023. Prior to the IPO, the warrants were classified as a liability in the condensed consolidated balance sheets and were remeasured at each balance sheet date using the Black-Scholes option pricing model, and any changes in fair value were recorded in other income (expense), net in the Company's condensed consolidated statements of operations. Immediately prior to the completion of the IPO in June 2021, these outstanding redeemable convertible preferred stock warrants were converted to Class B common stock warrants and the fair value of the liability as of that date was reclassified into the Company’s Class B common stock and additional paid-in capital. In July 2021, both warrants were exercised and a total of 203,610 shares of Class B common stock were issued. In 2015 and 2016, in connection with prior loan agreements, the Company issued two warrants to the lender to purchase 231,348 and 621,066 shares of common stock, both at an exercise price of $0.053 per share. As of December 31, 2020, 231,348 and 438,180 warrants were fully vested and exercisable, and classified as equity instruments. Immediately prior to the completion of the IPO, those warrants were converted to an equivalent number of shares of Class B common stock warrants. In June 2021, both warrants were exercised and a total of 668,412 shares of Class B common stock were issued. In September 2020, the Company issued a warrant to a Customer to purchase up to 750,000 shares of the Company’s common stock over a period of five years, ending in September 2025, at an exercise price of $0.01 per share, for a total fair value of $5.7 million. The warrant becomes exercisable when the vesting conditions are met. The warrant vesting is contingent on certain performance conditions, which include the Customer reaching certain annual transaction count thresholds over the five-year contract term. This warrant is classified as an equity instrument and expires in September 2025. It is treated as consideration payable to a Customer and recorded as a reduction to net revenue based on the probability of vesting conditions being met and the grant date fair value of the warrant. As of September 30, 2021, 25,900 warrants were vested and the Company recorded $0.1 million and $0.2 million as a reduction to net revenue during the three and nine months then ended, respectively. The fair value of the warrant was estimated using the Black-Scholes option pricing model and the following assumptions as of the date of the grant: Dividend yield 0.0% Expected volatility 50.0% Contract term (in years) 5.0 Risk-free interest rate 0.3% In March 2021, the Company issued warrants to two Customers to purchase up to 1,100,000 and 50,000 shares of the Company’s common stock, respectively, over a period of four years, ending in April 2025, at an exercise price of $0.01 per share. The aggregate grant date fair value of these warrants was $26.4 million. The warrants’ vesting is contingent on certain performance conditions, which include issuing a specified percentage of new cards on the Company’s Platform over a three-year measurement period. The warrants are treated as consideration payable to a Customer and the grant date fair value of the warrants will be recorded as a reduction to net revenue based on the probability of vesting conditions being met. As of September 30, 2021, 183,334 warrants had vested and the Company recorded $2.0 million and $3.0 million as a reduction to net revenue during the three and nine months ended September 30, 2021, respectively. The fair value of the warrants was estimated using the Black-Scholes option pricing model and the following weighted average assumptions: Dividend yield 0.0% Expected volatility 50.0% Contract term (in years) 4.0 Risk-free interest rate 0.6%

Net Loss Per Share Attributable

Net Loss Per Share Attributable to Common Stockholders	9 Months Ended
	Sep. 30, 2021
Earnings Per Share [Abstract]
Net Loss Per Share Attributable to Common Stockholders	Net Loss Per Share Attributable to Common Stockholders The Company presents basic and diluted net loss per share attributable to common stockholders in conformity with the two-class method required for participating securities. Prior to the completion of the IPO, all series of redeemable convertible preferred stock were considered participating securities. Immediately prior to the completion of the IPO, all shares of redeemable convertible preferred stock then outstanding were converted into shares of Class B common stock. The Company has not allocated net loss attributable to common stockholders to redeemable convertible preferred stock in any period presented because the holders of its redeemable convertible preferred stock were not contractually obligated to share in losses. The Company calculates basic net loss per share attributable to common stockholders by dividing net loss attributable to common stockholders by the weighted-average number of shares of common stock outstanding during the period. Diluted net loss per share attributable to common stockholders gives effect to all potential shares of common stock, including common stock issuable upon conversion of redeemable convertible preferred stock and redeemable convertible preferred stock warrants, stock options, RSUs and common stock warrants to the extent these are dilutive. The Company calculated basic and diluted net loss per share attributable to common stockholders as follows: Three Months Ended September 30, Nine Months Ended September 30, 2021 2020 2021 2020 Numerator Net loss attributable to Class A and Class B common stockholders $ (45,730) $ (12,298) $ (127,122) $ (33,935) Denominator Weighted-average shares used in computing net loss per share attributable to Class A and Class B common stockholders, basic and diluted 538,896,513 124,225,475 302,967,155 120,931,681 Net loss per share attributable to Class A and Class B common stockholders, basic and diluted $ (0.08) $ (0.10) $ (0.42) $ (0.28) Basic net loss per share is the same as diluted net loss per share because the Company reported a net loss for the three and nine months ended September 30, 2021 and 2020. The rights, including the liquidation and dividend rights, of the holders of Class A common stock and Class B common stock are identical, except with respect to voting. As the liquidation and dividend rights are identical for Class A common stock and Class B common stock, the undistributed earnings are allocated on a proportionate basis and the resulting loss per share will, therefore, be the same for both Class A common stock and Class B common stock on an individual or combined basis. Potentially dilutive securities that were excluded from the computation of diluted net loss per share because including them would have had an anti-dilutive effect were as follows: As of September 30, 2021 2020 Redeemable convertible preferred stock, all series — 351,844,340 Warrants to purchase redeemable convertible preferred stock — 203,610 Warrants to purchase Class B common stock 1,900,000 1,419,528 Stock options outstanding, including early exercise of options 46,056,552 24,908,901 Unvested RSUs outstanding 9,216,185 3,784,845 Total 57,172,737 382,161,224

Income Tax

Income Tax	9 Months Ended
	Sep. 30, 2021
Income Tax Disclosure [Abstract]
Income Tax	Income TaxThe provision for income taxes was not significant for all periods presented. The Company’s effective tax rate was approximately zero percent for all periods presented. The effective tax rate was lower than the U.S. federal statutory rate primarily because of the domestic valuation allowances. For all periods presented, the Company recognized an insignificant provision related to foreign income taxes.

Concentration of Risks and Sign

Concentration of Risks and Significant Customers	9 Months Ended
	Sep. 30, 2021
Risks and Uncertainties [Abstract]
Concentration of Risks and Significant Customers	Concentration Risks and Significant Customers Financial instruments that potentially expose the Company to concentration of credit risk consist of cash and cash equivalents, marketable securities, accounts receivable and unbilled Customers' receivable, or collectively, Customers' receivables, and settlements receivable. Cash on deposit with financial institutions may, at times, exceed federally insured limits. Management believes that these financial institutions are financially sound and, accordingly, minimal credit risk exists. Cash and cash equivalents as of September 30, 2021 and December 31, 2020 include $1.2 billion and $203.6 million, respectively, of investments in three money market mutual funds, which invest primarily in securities issued by the U.S. Government or U.S. Government agencies. As of September 30, 2021, marketable securities were $409.0 million, and there was no concentration of securities of the same issuer with an aggregate fair value greater than 5% of the total balance, except for U.S. Treasuries, which amounted to $374.6 million, or 92% of the marketable securities. All debt securities within the Company's portfolio are investment grade. As of December 31, 2020, marketable securities were $149.9 million, and there was no concentration of securities of the same issuer with an aggregate fair value greater than 5% of the total balance, except for U.S. Treasuries, which amounted to $125.9 million, or 84% of the marketable securities. All debt securities within the Company's portfolio are investment grade. A significant portion of the Company's payment transactions are settled through one Issuing Bank, Sutton Bank. For the three months ended September 30, 2021 and 2020, 89% and 96% of Total Processing Volume, which is the total dollar amount of payments processed through the Company’s Platform, net of returns and chargebacks, was settled through Sutton Bank, respectively. For the nine months ended September 30, 2021 and 2020, 92% and 96% of Total Processing Volume was settled through Sutton Bank, respectively. A significant portion of the Company's revenue is derived from one Customer. For the three months ended September 30, 2021 and 2020, this Customer accounted for 68% and 72% of the Company’s net revenue, respectively. For the nine months ended September 30, 2021 and 2020, this Customer accounted for 71% and 69% of the Company’s net revenue, respectively. For the three and nine months ended September 30, 2020, another Customer accounted for 9% and 11% of the Company’s net revenue, respectively.

Related Party Transactions

Related Party Transactions	9 Months Ended
	Sep. 30, 2021
Related Party Transactions [Abstract]
Related Party Transactions	Related Party Transactions The Company may enter into transactions with related parties.

Subsequent Events

Subsequent Events	9 Months Ended
	Sep. 30, 2021
Subsequent Events [Abstract]
Subsequent Events	Subsequent EventsThe Company has evaluated events through November 10, 2021, the date the financial statements as of and for the three and nine months ended September 30, 2021 were available to be issued. No subsequent events were identified that would have required recognition or disclosure in the financial statements.

Summary of Significant Accoun_2

Summary of Significant Accounting Policies (Policies)	9 Months Ended
	Sep. 30, 2021
Accounting Policies [Abstract]
Basis of Presentation	Basis of Presentation The accompanying unaudited condensed consolidated financial statements have been prepared in accordance with generally accepted accounting principles in the United States of America, or GAAP, and the applicable rules and regulations of the Securities and Exchange Commission, or the SEC, for interim reporting. Certain information and note disclosures included in our annual financial statements prepared in accordance with GAAP have been condensed or omitted pursuant to such rules and regulations. The condensed consolidated balance sheet as of December 31, 2020 has been derived from our audited consolidated financial statements, which are included in the prospectus dated June 8, 2021, as filed with the SEC pursuant to Rule 424(b) under the Securities Act of 1933, or the Prospectus. The accompanying condensed consolidated financial statements should be read in conjunction with our consolidated financial statements and notes thereto included in the Prospectus. The accompanying unaudited condensed consolidated financial statements include the accounts of the Company and its wholly owned subsidiaries. All intercompany balances and transactions have been eliminated in consolidation. In the opinion of management, the accompanying condensed consolidated financial statements reflect all adjustments of a normal recurring nature considered necessary for a fair presentation of the Company's consolidated financial position, results of operations, comprehensive loss, and cash flows for the interim periods presented. The interim results for the three and nine months ended September 30, 2021 are not necessarily indicative of the results that may be expected for the year ending December 31, 2021, or for any other future annual or interim period.
Use of Estimates	Use of Estimates The preparation of the financial statements requires management to make estimates and assumptions relating to reported amounts of assets and liabilities, disclosure of contingent assets and liabilities, and reported amounts of revenue and expenses. Significant estimates and assumptions relate to the estimation of variable consideration in contracts with Customers, collectability of accounts receivable, reserve for contract contingencies and processing errors, the useful lives of property and equipment, the incremental borrowing rate used to determine operating lease liabilities, the fair value of equity awards and warrants, and share-based compensation. Actual results could differ materially from these estimates.
Segment Information	Segment Information The Company operates as a single operating segment. The Company's chief operating decision maker is its Chief Executive Officer, who reviews financial information presented on a consolidated basis for purposes of making operating decisions, assessing financial performance, allocating resources and evaluating the Company's financial performance.
Restricted Cash	Restricted Cash Restricted cash consists of deposits with financial institutions that issue payment cards (credit, debit, or prepaid) either on their own behalf or on behalf of businesses that issue customized card products to their end users, or Issuing Banks, to provide the Issuing Bank collateral in the event that Customers’ funds are not deposited at the Issuing Banks in time to settle Customers’ transactions with the networks that provide the infrastructure for settlement and card payment information flows, or Card Networks. Restricted cash also includes cash used to secure a letter of credit for the Company’s lease of its office headquarters in Oakland, California.
Deferred Offering Costs	Deferred Offering Costs Deferred offering costs consist primarily of accounting, legal, and other fees related to the IPO. Upon the completion of the IPO in June 2021, the deferred offering costs were reclassified to stockholders’ equity and recorded net against the proceeds from the IPO.
New Accounting Standards Adopted and Not Yet Adopted	New Accounting Standards Adopted In August 2018, the Financial Accounting Standards Board, or the FASB, issued Accounting Standards Update, or ASU, No. 2018-15, Intangibles—Goodwill and Other— Internal-Use Software (Subtopic 350-40), which aligns the requirements for capitalizing implementation costs incurred in a hosting arrangement that is a service contract with the requirements for capitalizing implementation costs incurred to develop or obtain internal-use software (and hosting arrangements that include an internal use software license). The accounting for the service element of a hosting arrangement that is a service contract is not affected by the amendments in this ASU. The Company adopted the new standard 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. New Accounting Standards Not Yet Adopted As an emerging growth company, the Jumpstart Our Business Startups Act, or the JOBS Act, allows the Company to delay adoption of new or revised accounting pronouncements applicable to public companies until such pronouncements are made applicable to private companies. The Company has elected to use this extended transition period under the JOBS Act. The adoption date discussed below reflects this election. In June 2016, the FASB issued ASU No. 2016-13, Financial instruments – Credit Losses (Topic 326): Measurement of Credit Losses on Financial Instruments . ASU 2016-13 replaces the incurred loss model with the current expected credit loss, or CECL, model to estimate credit losses for financial assets measured at amortized cost and certain off-balance sheet credit exposures. It also eliminates the concept of other-than-temporary impairment and requires credit losses related to available-for-sale debt securities to be recorded through an allowance for credit losses rather than as a reduction in the amortized cost basis of the securities. The CECL model requires a company to estimate credit losses expected over the life of the financial assets based on historical experience, current conditions and reasonable and supportable forecasts. The guidance will be effective for the Company beginning January 1, 2023, and interim periods therein. The amendment requires a modified retrospective approach by recording a cumulative-effect adjustment to retained earnings as of the beginning of the period of adoption. Early adoption is permitted. The Company is still evaluating the impact this ASU will have on its condensed consolidated financial statements.

Revenue (Tables)

Revenue (Tables)	9 Months Ended
	Sep. 30, 2021
Revenue from Contract with Customer [Abstract]
Disaggregation of Revenue	Disaggregation of Revenue The following table provides information about disaggregated revenue from Customers: Three Months Ended September 30, Nine Months Ended September 30, 2021 2020 2021 2020 Platform services revenue, net $ 126,388 $ 81,620 $ 350,884 $ 195,260 Other services revenue 5,124 2,686 10,877 6,836 Total net revenue $ 131,512 $ 84,306 $ 361,761 $ 202,096
Contract with Customer, Contract Asset, Contract Liability, and Receivable	Contract Balances The following table provides information about contract assets and deferred revenue: Contract balance Balance sheet line reference September 30, December 31, Contract assets - current Prepaid expenses and other current assets $ 672 $ 118 Contract assets - non-current Other assets 830 294 Total contract assets $ 1,502 $ 412 Deferred revenue - current Accrued expenses and other current liabilities $ 8,978 $ 3,983 Deferred revenue - non-current Other liabilities 6,882 8,865 Total deferred revenue $ 15,860 $ 12,848

Marketable Securities (Tables)

Marketable Securities (Tables)	9 Months Ended
	Sep. 30, 2021
Investments [Abstract]
Marketable Securities	The amortized cost, unrealized gain (loss), and estimated fair value of the Company's investments in securities available for sale consisted of the following: September 30, 2021 Amortized Cost Unrealized Gain Unrealized Loss Estimated Fair Value Marketable securities U.S. government securities $ 374,849 $ 1 $ (257) $ 374,593 Commercial paper 16,880 — — 16,880 Asset-backed securities 2,017 — — 2,017 Corporate debt securities 15,468 3 (7) 15,464 Total marketable securities $ 409,214 $ 4 $ (264) $ 408,954 December 31, 2020 Amortized Cost Unrealized Gain Unrealized Loss Estimated Fair Value Marketable securities U.S. government securities $ 125,823 $ 47 $ (6) $ 125,864 Commercial paper 4,991 — — 4,991 Asset-backed securities 4,294 21 — 4,315 Corporate debt securities 14,683 52 (2) 14,733 Total marketable securities $ 149,791 $ 120 $ (8) $ 149,903
Schedule of Available-for-sale Securities Reconciliation	The following table summarizes the stated maturities of the Company’s marketable securities: September 30, 2021 December 31, 2020 Amortized Cost Estimated Fair Value Amortized Cost Estimated Fair Value Due within one year $ 56,756 $ 56,756 $ 149,791 $ 149,903 Due after one year through two years 352,458 352,198 — — Total $ 409,214 $ 408,954 $ 149,791 $ 149,903

Fair Value Measurements (Tables

Fair Value Measurements (Tables)	9 Months Ended
	Sep. 30, 2021
Fair Value Disclosures [Abstract]
Schedule of Assets and Liabilities at Fair Value	The following tables present the fair value hierarchy for assets and liabilities measured at fair value: September 30, 2021 Level 1 Level 2 Level 3 Total Fair Value Cash equivalents Money market funds $ 1,227,637 $ — $ — $ 1,227,637 Marketable securities U.S. government securities 374,593 — — 374,593 Commercial paper — 16,880 — 16,880 Asset-backed securities — 2,017 — 2,017 Corporate debt securities — 15,464 — 15,464 Total assets $ 1,602,230 $ 34,361 $ — $ 1,636,591 December 31, 2020 Level 1 Level 2 Level 3 Total Fair Value Cash equivalents Money market funds $ 203,592 $ — $ — $ 203,592 Marketable securities U.S. government securities 125,864 — — 125,864 Commercial paper — 4,991 — 4,991 Asset-backed securities — 4,315 — 4,315 Corporate debt securities — 14,733 — 14,733 Total assets $ 329,456 $ 24,039 $ — $ 353,495 Other liabilities Redeemable convertible preferred stock warrants $ — $ — $ 2,517 $ 2,517 Total liabilities $ — $ — $ 2,517 $ 2,517
Schedule of Fair Value Assumptions	The fair value of the redeemable convertible preferred stock warrant liabilities was estimated using the following assumptions: June 9, December 31, Dividend yield 0.00% 0.00% Expected volatility 49.93% 49.93% Expected term (in years) 2.34 2.78 Risk-free interest rate 0.31% 0.17% Fair value of Series B redeemable convertible preferred stock $27.00 $12.66 The fair value of the warrant was estimated using the Black-Scholes option pricing model and the following assumptions as of the date of the grant: Dividend yield 0.0% Expected volatility 50.0% Contract term (in years) 5.0 Risk-free interest rate 0.3% The fair value of the warrants was estimated using the Black-Scholes option pricing model and the following weighted average assumptions: Dividend yield 0.0% Expected volatility 50.0% Contract term (in years) 4.0 Risk-free interest rate 0.6%
Summary of Changes in Fair Value	The following table sets forth a summary of the changes in the fair value of the redeemable convertible preferred stock warrant liabilities: September 30, December 31, Balance, beginning of the period $ 2,517 $ 569 Remeasurement of redeemable convertible preferred stock warrant liabilities 2,921 1,948 Reclassification of redeemable convertible preferred stock warrant liabilities to common stock and additional paid-in capital upon initial public offering (5,438) — Balance, end of the period $ — $ 2,517

Certain Balance Sheet Compone_2

Certain Balance Sheet Components (Tables)	9 Months Ended
	Sep. 30, 2021
Organization, Consolidation and Presentation of Financial Statements [Abstract]
Prepaid Expenses and Other Current Assets	Prepaid Expenses and Other Current Assets Prepaid expenses and other current assets consisted of the following: September 30, December 31, Prepaid expenses $ 12,210 $ 6,162 Card program deposits 2,167 2,174 Other current assets 5,482 3,125 Prepaid expenses and other current assets $ 19,859 $ 11,461
Property and Equipment, net	Property and Equipment, net Property and equipment consisted of the following: September 30, December 31, Leasehold improvements $ 8,110 8,110 Computer equipment 8,917 7,634 Furniture and fixtures 2,459 2,333 Internally developed and purchased software 2,905 1,299 22,391 19,376 Accumulated depreciation and amortization (12,200) (9,899) Property and equipment, net $ 10,191 $ 9,477
Accrued Expenses and Other Current Liabilities	Accrued Expenses and Other Current Liabilities Accrued expenses and other current liabilities consisted of the following: September 30, December 31, Accrued costs of revenue $ 34,086 $ 24,529 Reserve for contract contingencies and processing errors 11,686 9,537 Accrued compensation and benefits 25,568 14,078 Deferred revenue 8,978 3,983 Operating lease liabilities, current portion 2,935 2,771 Accrued professional services 2,552 867 Other accrued liabilities 11,801 4,780 Accrued expenses and other current liabilities $ 97,606 $ 60,545
Other Liabilities	Other Liabilities Other liabilities consisted of the following: September 30, December 31, Deferred revenue, net of current portion $ 6,882 $ 8,865 Other long-term liabilities 1,196 1,587 Other liabilities $ 8,078 $ 10,452

Commitments and Contingencies (

Commitments and Contingencies (Tables)	9 Months Ended
	Sep. 30, 2021
Commitments and Contingencies Disclosure [Abstract]
Components lease costs	The Company's operating lease costs are as follows: Three Months Ended September 30, Nine Months Ended September 30, 2021 2020 2021 2020 Operating lease cost $ 843 $ 877 $ 2,581 $ 2,645 Variable lease cost 65 112 135 336 Short-term lease cost 237 71 368 206 Total lease cost $ 1,145 $ 1,060 $ 3,084 $ 3,187 The weighted average remaining operating lease term and the weighted average discount rate used in the calculation of the Company's lease assets and lease liabilities were as follows: September 30, December 31, Weighted average remaining operating lease term (in years) 4.3 5.1 Weighted average discount rate 7.7% 7.7% Supplemental cash flow information related to the Company's operating leases was as follows: Three Months Ended September 30, Nine Months Ended September 30, 2021 2020 2021 2020 Cash paid for operating lease liabilities $ 1,007 $ 900 $ 3,072 $ 2,699 Operating lease right-of-use assets obtained in exchange for new operating lease liabilities $ — $ — $ — $ 192
Future minimum lease payments	Maturities of operating lease liabilities by year are as follows as of September 30, 2021: Remainder of 2021 $ 1,012 2022 4,112 2023 4,239 2024 4,472 2025 4,599 Thereafter 780 Total lease payments 19,214 Less imputed interest (3,061) Total operating lease liabilities $ 16,153

Stock Incentive Plans (Tables)

Stock Incentive Plans (Tables)	9 Months Ended
	Sep. 30, 2021
Share-based Compensation Arrangement by Share-based Payment Award
Schedule of Share-based Compensation Expense	The following table summarizes the share-based compensation expense recognized for the different stock incentive plans discussed below: Three Months Ended September 30, Nine Months Ended September 30, 2021 2020 2021 2020 Stock options (1) $ 22,180 $ 2,907 $ 47,322 $ 8,134 Secondary sales of common stock — 9,050 11,642 10,486 Restricted stock units 15,882 — 45,948 — Employee Stock Purchase Plan 903 — 981 — Total $ 38,965 $ 11,957 $ 105,893 $ 18,620 (1) Includes the share-based compensation expense recognized for employees, non-employees and the CEO Long-Term Performance Award. During the three and nine months ended September 30, 2021, share-based compensation expense recognized for the CEO Long-Term Performance Award was $13.4 million and $24.8 million, respectively. A summary of the Company's stock option activity under both stock incentive plans was as follows: Number of Options Weighted-Average Exercise Price per Share Weighted-Average Remaining Contractual Life Aggregate Intrinsic Value (1) Balance as of December 31, 2020 (2) 23,421,374 $ 1.35 8.33 years $ 248,002 Granted 29,113,555 20.07 Exercised (3,236,786) 1.06 Canceled and forfeited (3,241,591) 2.89 Balance as of September 30, 2021 (2) 46,056,552 $ 13.09 8.66 years $ 417,075 Vested as of September 30, 2021 9,922,355 $ 1.43 6.73 years $ 219,482 (1) Intrinsic value is calculated based on the difference between the exercise price of in-the-money-stock options and the fair value of the common stock as of the respective balance sheet dates. (2) The 2011 Plan allows for early exercise of stock options and these balances include all exercisable stock options regardless of vesting status. The CEO Long-Term Performance Award is divided into seven equal tranches which vest upon the achievement of the following Company stock price hurdles: Tranche Company Stock Price Hurdle Number of Options Eligible to Vest 1 $67.50 2,826,884 2 $78.98 2,826,884 3 $92.40 2,826,884 4 $108.11 2,826,884 5 $126.49 2,826,884 6 $147.99 2,826,884 7 $173.15 2,826,884 Total 19,788,188
Schedule of Nonvested Restricted Stock Units Activity	A summary of the Company's RSUs activity under both stock incentive plans was as follows: Number of Restricted Stock Units Weighted-average grant date fair value per share Balance as of December 31, 2020 4,430,336 $ 4.93 Granted 7,420,972 20.58 Vested (1,985,645) 7.60 Canceled and forfeited (649,478) 11.78 Balance as of September 30, 2021 9,216,185 $ 15.85
Stock Options
Share-based Compensation Arrangement by Share-based Payment Award
Schedule of Share-based Payment Award, Stock Options, Valuation Assumptions	The fair value of stock options granted was estimated using the Black-Scholes option pricing model and the following weighted average assumptions: Three Months Ended September 30, Nine Months Ended September 30, 2021 2020 2021 2020 Dividend yield 0.0% 0.0% 0.0% 0.0% Expected volatility 57.48% 49.93% 54.15% 48.11% Expected term (in years) 6.08 6.02 6.73 6.02 Risk-free interest rate 1.18% 0.36% 1.22% 0.54%

Warrants to Purchase Common S_2

Warrants to Purchase Common Stock (Tables)	9 Months Ended
	Sep. 30, 2021
Class of Warrant or Right [Line Items]
Schedule of Fair Value Assumptions	The fair value of the redeemable convertible preferred stock warrant liabilities was estimated using the following assumptions: June 9, December 31, Dividend yield 0.00% 0.00% Expected volatility 49.93% 49.93% Expected term (in years) 2.34 2.78 Risk-free interest rate 0.31% 0.17% Fair value of Series B redeemable convertible preferred stock $27.00 $12.66 The fair value of the warrant was estimated using the Black-Scholes option pricing model and the following assumptions as of the date of the grant: Dividend yield 0.0% Expected volatility 50.0% Contract term (in years) 5.0 Risk-free interest rate 0.3% The fair value of the warrants was estimated using the Black-Scholes option pricing model and the following weighted average assumptions: Dividend yield 0.0% Expected volatility 50.0% Contract term (in years) 4.0 Risk-free interest rate 0.6%
September 2020 Common Stock Warrants
Class of Warrant or Right [Line Items]
Schedule of Stockholders' Equity Note, Warrants or Rights	The fair value of the warrant was estimated using the Black-Scholes option pricing model and the following assumptions as of the date of the grant: Dividend yield 0.0% Expected volatility 50.0% Contract term (in years) 5.0 Risk-free interest rate 0.3%
March 2021 Common Stock Warrants
Class of Warrant or Right [Line Items]
Schedule of Stockholders' Equity Note, Warrants or Rights	The fair value of the warrants was estimated using the Black-Scholes option pricing model and the following weighted average assumptions: Dividend yield 0.0% Expected volatility 50.0% Contract term (in years) 4.0 Risk-free interest rate 0.6%

Net Loss Per Share Attributab_2

Net Loss Per Share Attributable to Common Stockholders (Tables)	9 Months Ended
	Sep. 30, 2021
Earnings Per Share [Abstract]
Schedule of Earnings Per Share, Basic and Diluted	The Company calculated basic and diluted net loss per share attributable to common stockholders as follows: Three Months Ended September 30, Nine Months Ended September 30, 2021 2020 2021 2020 Numerator Net loss attributable to Class A and Class B common stockholders $ (45,730) $ (12,298) $ (127,122) $ (33,935) Denominator Weighted-average shares used in computing net loss per share attributable to Class A and Class B common stockholders, basic and diluted 538,896,513 124,225,475 302,967,155 120,931,681 Net loss per share attributable to Class A and Class B common stockholders, basic and diluted $ (0.08) $ (0.10) $ (0.42) $ (0.28)
Schedule of Antidilutive Securities Excluded from Computation of Earnings Per Share	Potentially dilutive securities that were excluded from the computation of diluted net loss per share because including them would have had an anti-dilutive effect were as follows: As of September 30, 2021 2020 Redeemable convertible preferred stock, all series — 351,844,340 Warrants to purchase redeemable convertible preferred stock — 203,610 Warrants to purchase Class B common stock 1,900,000 1,419,528 Stock options outstanding, including early exercise of options 46,056,552 24,908,901 Unvested RSUs outstanding 9,216,185 3,784,845 Total 57,172,737 382,161,224

Business Overview and Basis o_2

Business Overview and Basis of Presentation (Details) $ / shares in Units, $ in Thousands	May 31, 2021voteshares	Jun. 30, 2021USD ($)$ / sharesshares	Sep. 30, 2021USD ($)shares	Jun. 30, 2021USD ($)$ / shares	Mar. 31, 2021USD ($)	Sep. 30, 2020USD ($)	Jun. 30, 2020USD ($)	Mar. 31, 2020USD ($)	Sep. 30, 2021USD ($)shares	Sep. 30, 2020USD ($)	Dec. 31, 2020USD ($)shares
Initial Public Offering
Proceeds from initial public offering, net of underwriters’ discounts and commissions									$ 1,319,809	$ 0
Payments of stock issuance costs									$ 3,134	1,231
Preferred Stock, shares authorized (in shares) | shares			100,000,000						100,000,000		0
Business Risks and Uncertainties
Net loss			$ 45,730	$ 68,554	$ 12,838	$ 12,298	$ 7,107	$ 14,530	$ 127,122	33,935
Accumulated deficit			380,646						380,646		$ 253,524
Cash and cash equivalents			1,260,220			$ 214,960			1,260,220	$ 214,960	$ 220,433
Marketable securities			$ 409,000						$ 409,000
Class A Common Stock
Initial Public Offering
Common stock, shares authorized (in shares) | shares	1,500,000,000		1,500,000,000						1,500,000,000		0
Number of vote (votes per share) | vote	1
Class B Common Stock
Initial Public Offering
Common stock, shares authorized (in shares) | shares	600,000,000		600,000,000						600,000,000		545,000,000
Number of vote (votes per share) | vote	10
Convertible preferred stock, shares, number of shares issued upon conversion (in shares) | shares	203,610		351,844,340						351,844,340
Preferred stock, convertible, conversion raio			1						1
Number of common stock warrants converted to Class B common stock warrants (in warrants) | shares	2,569,528
Preferred Stock
Initial Public Offering
Preferred Stock, shares authorized (in shares) | shares	100,000,000
IPO | Class A Common Stock
Initial Public Offering
Sale of stock, number of shares issued in transaction (in shares) | shares		52,272,727
Share price (in dollars per share) | $ / shares		$ 27		$ 27
Proceeds from initial public offering, net of underwriters’ discounts and commissions		$ 1,300,000
Payments for commissions and discounts		91,600
Payments of stock issuance costs		$ 7,500
Over-Allotment Option | Class A Common Stock
Initial Public Offering
Sale of stock, number of shares issued in transaction (in shares) | shares		6,818,181

Revenue - Disaggregation of Rev

Revenue - Disaggregation of Revenue (Details) - USD ($) $ in Thousands	3 Months Ended		9 Months Ended
	Sep. 30, 2021	Sep. 30, 2020	Sep. 30, 2021	Sep. 30, 2020
Disaggregation of Revenue [Line Items]
Net revenue	$ 131,512	$ 84,306	$ 361,761	$ 202,096
Platform services revenue, net
Disaggregation of Revenue [Line Items]
Net revenue	126,388	81,620	350,884	195,260
Other services revenue
Disaggregation of Revenue [Line Items]
Net revenue	$ 5,124	$ 2,686	$ 10,877	$ 6,836

Revenue - Contract Assets and D

Revenue - Contract Assets and Deferred Revenue (Details) - USD ($) $ in Thousands	3 Months Ended		9 Months Ended
	Sep. 30, 2021	Sep. 30, 2020	Sep. 30, 2021	Sep. 30, 2020	Dec. 31, 2020
Disaggregation of Revenue [Line Items]
Total contract assets	$ 1,502		$ 1,502		$ 412
Deferred revenue	8,978		8,978		3,983
Deferred revenue - non-current	6,882		6,882		8,865
Total deferred revenue	15,860		15,860		12,848
Deferred revenue recognized during the period	3,300	$ 1,000	2,900	$ 600
Prepaid expenses and other current assets
Disaggregation of Revenue [Line Items]
Contract assets - current	672		672		118
Other assets
Disaggregation of Revenue [Line Items]
Contract assets - non-current	830		830		294
Accrued expenses and other current liabilities
Disaggregation of Revenue [Line Items]
Deferred revenue	8,978		8,978		3,983
Other liabilities
Disaggregation of Revenue [Line Items]
Deferred revenue - non-current	$ 6,882		$ 6,882		$ 8,865

Marketable Securities - Unreali

Marketable Securities - Unrealized Gain (Loss) on Investments (Details) - USD ($) $ in Thousands	Sep. 30, 2021	Dec. 31, 2020
Debt Securities, Available-for-sale [Line Items]
Amortized Cost	$ 409,214	$ 149,791
Unrealized Gain	4	120
Unrealized Loss	(264)	(8)
Marketable securities	408,954	149,903
U.S. government securities
Debt Securities, Available-for-sale [Line Items]
Amortized Cost	374,849	125,823
Unrealized Gain	1	47
Unrealized Loss	(257)	(6)
Marketable securities	374,593	125,864
Commercial paper
Debt Securities, Available-for-sale [Line Items]
Amortized Cost	16,880	4,991
Unrealized Gain	0	0
Unrealized Loss	0	0
Marketable securities	16,880	4,991
Asset-backed securities
Debt Securities, Available-for-sale [Line Items]
Amortized Cost	2,017	4,294
Unrealized Gain	0	21
Unrealized Loss	0	0
Marketable securities	2,017	4,315
Corporate debt securities
Debt Securities, Available-for-sale [Line Items]
Amortized Cost	15,468	14,683
Unrealized Gain	3	52
Unrealized Loss	(7)	(2)
Marketable securities	$ 15,464	$ 14,733

Marketable Securities - Narrati

Marketable Securities - Narrative (Details) - investment	Sep. 30, 2021	Dec. 31, 2020
Investments [Abstract]
Number of marketable securities in unrealized loss positions	16	6

Marketable Securities - Stated

Marketable Securities - Stated Maturities of Marketable Securities (Details) - USD ($) $ in Thousands	Sep. 30, 2021	Dec. 31, 2020
Amortized Cost
Due within one year	$ 56,756	$ 149,791
Due after one year through two years	352,458	0
Amortized Cost	409,214	149,791
Estimated Fair Value
Due within one year	56,756	149,903
Due after one year through two years	352,198	0
Total	$ 408,954	$ 149,903

Fair Value Measurements - Recur

Fair Value Measurements - Recurring Fair Value Measurements (Details) - USD ($) $ in Thousands	Sep. 30, 2021	Dec. 31, 2020
Assets
Marketable securities	$ 408,954	$ 149,903
Other liabilities
Redeemable convertible preferred stock warrant liabilities	0	2,517
Fair Value, Measurements, Recurring
Assets
Total assets	1,636,591	353,495
Other liabilities
Total liabilities		2,517
Fair Value, Measurements, Recurring | Redeemable convertible preferred stock warrants
Other liabilities
Redeemable convertible preferred stock warrant liabilities		2,517
Fair Value, Measurements, Recurring | Money market funds
Assets
Money market funds	1,227,637	203,592
Fair Value, Measurements, Recurring | U.S. government securities
Assets
Marketable securities	374,593	125,864
Fair Value, Measurements, Recurring | Commercial paper
Assets
Marketable securities	16,880	4,991
Fair Value, Measurements, Recurring | Asset-backed securities
Assets
Marketable securities	2,017	4,315
Fair Value, Measurements, Recurring | Corporate debt securities
Assets
Marketable securities	15,464	14,733
Fair Value, Measurements, Recurring | Fair Value, Inputs, Level 1
Assets
Total assets	1,602,230	329,456
Other liabilities
Total liabilities		0
Fair Value, Measurements, Recurring | Fair Value, Inputs, Level 1 | Redeemable convertible preferred stock warrants
Other liabilities
Redeemable convertible preferred stock warrant liabilities		0
Fair Value, Measurements, Recurring | Fair Value, Inputs, Level 1 | Money market funds
Assets
Money market funds	1,227,637	203,592
Fair Value, Measurements, Recurring | Fair Value, Inputs, Level 1 | U.S. government securities
Assets
Marketable securities	374,593	125,864
Fair Value, Measurements, Recurring | Fair Value, Inputs, Level 1 | Commercial paper
Assets
Marketable securities	0	0
Fair Value, Measurements, Recurring | Fair Value, Inputs, Level 1 | Asset-backed securities
Assets
Marketable securities	0	0
Fair Value, Measurements, Recurring | Fair Value, Inputs, Level 1 | Corporate debt securities
Assets
Marketable securities	0	0
Fair Value, Measurements, Recurring | Fair Value, Inputs, Level 2
Assets
Total assets	34,361	24,039
Other liabilities
Total liabilities		0
Fair Value, Measurements, Recurring | Fair Value, Inputs, Level 2 | Redeemable convertible preferred stock warrants
Other liabilities
Redeemable convertible preferred stock warrant liabilities		0
Fair Value, Measurements, Recurring | Fair Value, Inputs, Level 2 | Money market funds
Assets
Money market funds	0	0
Fair Value, Measurements, Recurring | Fair Value, Inputs, Level 2 | U.S. government securities
Assets
Marketable securities	0	0
Fair Value, Measurements, Recurring | Fair Value, Inputs, Level 2 | Commercial paper
Assets
Marketable securities	16,880	4,991
Fair Value, Measurements, Recurring | Fair Value, Inputs, Level 2 | Asset-backed securities
Assets
Marketable securities	2,017	4,315
Fair Value, Measurements, Recurring | Fair Value, Inputs, Level 2 | Corporate debt securities
Assets
Marketable securities	15,464	14,733
Fair Value, Measurements, Recurring | Fair Value, Inputs, Level 3
Assets
Total assets	0	0
Other liabilities
Total liabilities		2,517
Fair Value, Measurements, Recurring | Fair Value, Inputs, Level 3 | Redeemable convertible preferred stock warrants
Other liabilities
Redeemable convertible preferred stock warrant liabilities		2,517
Fair Value, Measurements, Recurring | Fair Value, Inputs, Level 3 | Money market funds
Assets
Money market funds	0	0
Fair Value, Measurements, Recurring | Fair Value, Inputs, Level 3 | U.S. government securities
Assets
Marketable securities	0	0
Fair Value, Measurements, Recurring | Fair Value, Inputs, Level 3 | Commercial paper
Assets
Marketable securities	0	0
Fair Value, Measurements, Recurring | Fair Value, Inputs, Level 3 | Asset-backed securities
Assets
Marketable securities	0	0
Fair Value, Measurements, Recurring | Fair Value, Inputs, Level 3 | Corporate debt securities
Assets
Marketable securities	$ 0	$ 0

Fair Value Measurements - Rec_2

Fair Value Measurements - Recurring Fair Value Measurements, Unobservable Input Reconciliation (Details)	Sep. 30, 2021$ / shares	Dec. 31, 2020$ / shares
Dividend yield
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation [Line Items]
Measurement input (percent)	0	0
Expected volatility
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation [Line Items]
Measurement input (percent)	0.4993	0.4993
Expected term (in years)
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation [Line Items]
Warrant term (in years)	2 years 4 months 2 days	2 years 9 months 10 days
Risk-free interest rate
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation [Line Items]
Measurement input (percent)	0.0031	0.0017
Fair value of Series B redeemable convertible preferred stock
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation [Line Items]
Measurement input (percent)	27	12.66

Fair Value Measurements - Chang

Fair Value Measurements - Change in Fair Value of Redeemable Convertible Preferred Stock (Details) - USD ($) $ in Thousands	9 Months Ended	12 Months Ended
	Sep. 30, 2021	Dec. 31, 2020
Fair Value, Net Derivative Asset (Liability) Measured on Recurring Basis, Unobservable Input Reconciliation [Roll Forward]
Balance, beginning of the period	$ 2,517	$ 569
Remeasurement of redeemable convertible preferred stock warrant liabilities	2,921	1,948
Reclassification of redeemable convertible preferred stock warrant liabilities to common stock and additional paid-in capital upon initial public offering	(5,438)	0
Balance, end of the period	$ 0	$ 2,517

Certain Balance Sheet Compone_3

Certain Balance Sheet Components - Prepaid Expenses and Other Current Assets (Details) - USD ($) $ in Thousands	Sep. 30, 2021	Dec. 31, 2020
Organization, Consolidation and Presentation of Financial Statements [Abstract]
Prepaid expenses	$ 12,210	$ 6,162
Card program deposits	2,167	2,174
Other current assets	5,482	3,125
Prepaid expenses and other current assets	$ 19,859	$ 11,461

Certain Balance Sheet Compone_4

Certain Balance Sheet Components - Property and Equipment, net (Details) - USD ($) $ in Thousands	3 Months Ended		9 Months Ended
	Sep. 30, 2021	Sep. 30, 2020	Sep. 30, 2021	Sep. 30, 2020	Dec. 31, 2020
Property, Plant and Equipment [Line Items]
Property and equipment, gross	$ 22,391		$ 22,391		$ 19,376
Accumulated depreciation and amortization	(12,200)		(12,200)		(9,899)
Property and equipment, net	10,191		10,191		9,477
Depreciation and amortization	786	$ 901	2,567	$ 2,608
Capitalized internal-use software costs	100	$ 0	1,500	$ 0
Leasehold improvements
Property, Plant and Equipment [Line Items]
Property and equipment, gross	8,110		8,110		8,110
Computer equipment
Property, Plant and Equipment [Line Items]
Property and equipment, gross	8,917		8,917		7,634
Furniture and fixtures
Property, Plant and Equipment [Line Items]
Property and equipment, gross	2,459		2,459		2,333
Internally developed and purchased software
Property, Plant and Equipment [Line Items]
Property and equipment, gross	$ 2,905		$ 2,905		$ 1,299

Certain Balance Sheet Compone_5

Certain Balance Sheet Components - Accrued Expenses and Other Current Liabilities (Details) - USD ($) $ in Thousands	Sep. 30, 2021	Dec. 31, 2020
Organization, Consolidation and Presentation of Financial Statements [Abstract]
Accrued costs of revenue	$ 34,086	$ 24,529
Reserve for contract contingencies and processing errors	11,686	9,537
Accrued compensation and benefits	25,568	14,078
Deferred revenue	8,978	3,983
Operating lease liabilities, current portion	2,935	2,771
Accrued professional services	2,552	867
Other accrued liabilities	11,801	4,780
Accrued expenses and other current liabilities	$ 97,606	$ 60,545
Operating Lease, Liability, Current, Statement of Financial Position [Extensible Enumeration]

Certain Balance Sheet Compone_6

Certain Balance Sheet Components - Other Liabilities (Details) - USD ($) $ in Thousands	Sep. 30, 2021	Dec. 31, 2020
Organization, Consolidation and Presentation of Financial Statements [Abstract]
Deferred revenue, net of current portion	$ 6,882	$ 8,865
Other long-term liabilities	1,196	1,587
Other Liabilities, Noncurrent, Total	$ 8,078	$ 10,452

Commitments and Contingencies -

Commitments and Contingencies - Narrative (Details) ft² in Thousands, $ in Millions	3 Months Ended		9 Months Ended
	Sep. 30, 2021USD ($)ft²	Sep. 30, 2020USD ($)	Sep. 30, 2021USD ($)ft²	Sep. 30, 2020USD ($)	Dec. 31, 2016ft²
Guarantor Obligations
Area of real estate property | ft²	63		63		19
Purchase commitment	$ 9.1		$ 9.1
Purchase commitment period			5 years
Company matching contribution, percent			50.00%
Employer matching contribution, percent of employees' gross pay			6.00%
Requisite service period (in years)			1 year
Employer contribution amount	0.8	$ 0.5	$ 2.2	$ 1.4
Unfavorable Regulatory Action
Guarantor Obligations
Estimate of possible loss	6		6
Letter of Credit
Guarantor Obligations
Letters of credit, amount	1.5		1.5
Restricted Cash | Letter of Credit
Guarantor Obligations
Deposit assets	$ 1.5		$ 1.5

Commitments and Contingencies_2

Commitments and Contingencies - Lease Costs (Details) - USD ($) $ in Thousands	3 Months Ended		9 Months Ended
	Sep. 30, 2021	Sep. 30, 2020	Sep. 30, 2021	Sep. 30, 2020
Commitments and Contingencies Disclosure [Abstract]
Operating lease cost	$ 843	$ 877	$ 2,581	$ 2,645
Variable lease cost	65	112	135	336
Short-term lease cost	237	71	368	206
Total lease cost	$ 1,145	$ 1,060	$ 3,084	$ 3,187

Commitments and Contingencies_3

Commitments and Contingencies - Weighted Average Lease Term and Weighted Average Discount Rate (Details)	Sep. 30, 2021	Dec. 31, 2020
Commitments and Contingencies Disclosure [Abstract]
Weighted average remaining operating lease term (in years)	4 years 3 months 18 days	5 years 1 month 6 days
Weighted average discount rate	7.70%	7.70%

Commitments and Contingencies_4

Commitments and Contingencies - Lease Maturity Schedule (Details) $ in Thousands	Sep. 30, 2021USD ($)
Commitments and Contingencies Disclosure [Abstract]
Remainder of 2021	$ 1,012
2022	4,112
2023	4,239
2024	4,472
2025	4,599
Thereafter	780
Total lease payments	19,214
Less imputed interest	(3,061)
Total operating lease liabilities	$ 16,153
Operating Lease, Liability, Statement of Financial Position [Extensible Enumeration]	Accounts Payable and Accrued Liabilities

Commitments and Contingencies_5

Commitments and Contingencies - Supplemental Cash Flow Information (Details) - USD ($) $ in Thousands	3 Months Ended		9 Months Ended
	Sep. 30, 2021	Sep. 30, 2020	Sep. 30, 2021	Sep. 30, 2020
Commitments and Contingencies Disclosure [Abstract]
Cash paid for operating lease liabilities	$ 1,007	$ 900	$ 3,072	$ 2,699
Operating lease right-of-use assets obtained in exchange for new operating lease liabilities	$ 0	$ 0	$ 0	$ 192

Stock Incentive Plans - Schedul

Stock Incentive Plans - Schedule of Share-based Compensation Expense (Details) - USD ($) $ in Thousands	Jun. 08, 2021	Sep. 30, 2021	Sep. 30, 2020	Sep. 30, 2021	Sep. 30, 2020
Share-based Payment Arrangement, Expensed and Capitalized, Amount [Line Items]
Share-based compensation expense		$ 38,965	$ 11,957	$ 105,893	$ 18,620
Stock options
Share-based Payment Arrangement, Expensed and Capitalized, Amount [Line Items]
Share-based compensation expense		22,180	2,907	47,322	8,134
Secondary sales of common stock
Share-based Payment Arrangement, Expensed and Capitalized, Amount [Line Items]
Share-based compensation expense		0	9,050	11,642	10,486
Unvested RSUs outstanding
Share-based Payment Arrangement, Expensed and Capitalized, Amount [Line Items]
Share-based compensation expense	$ 23,100	15,882	0	45,948	0
Employee Stock Purchase Plan
Share-based Payment Arrangement, Expensed and Capitalized, Amount [Line Items]
Share-based compensation expense		$ 903	$ 0	$ 981	$ 0

Stock Incentive Plans - Narrati

Stock Incentive Plans - Narrative (Details) - USD ($) $ / shares in Units, $ in Thousands	Jun. 08, 2021	May 31, 2021	May 30, 2021	Apr. 30, 2021	Sep. 30, 2021	Sep. 30, 2020	Sep. 30, 2021	Sep. 30, 2020	Jan. 01, 2022
Share-based Compensation Arrangement by Share-based Payment Award
Share-based compensation expense					$ 38,965	$ 11,957	$ 105,893	$ 18,620
Stock Options
Share-based Compensation Arrangement by Share-based Payment Award
Granted (in shares)							29,113,555
Granted (in dollars per share)							$ 20.07
Stock Options | 2011 Plan
Share-based Compensation Arrangement by Share-based Payment Award
Fair market value of one share of common stock threshold							110.00%
Secondary sales of common stock
Share-based Compensation Arrangement by Share-based Payment Award
Share-based compensation expense					0	9,050	$ 11,642	10,486
CEO Long-Term Performance Award | Chief Executive Officer
Share-based Compensation Arrangement by Share-based Payment Award
Share-based compensation expense					13,400		$ 24,800
Compensation costs related to unvested outstanding stock options, period for recognition (in years)							4 years 3 months 18 days
Granted (in shares)			47,267	19,740,923
Granted (in dollars per share)		$ 23.40		$ 21.49
Weighted average grant date fair value (in dollars per share)							$ 10.53
Expected cost to be recognized over remaining derived service period					183,600		$ 183,600
Restricted Stock Units (RSUs)
Share-based Compensation Arrangement by Share-based Payment Award
Share-based compensation expense	$ 23,100				15,882	$ 0	$ 45,948	$ 0
Compensation costs related to unvested outstanding stock options, period for recognition (in years)							3 years 2 months 12 days
Award vesting period (in years)							4 years
CEO Long-term performance awards					136,400		$ 136,400
Employee Stock Option, Excluding CEO Long-term Performance Award
Share-based Compensation Arrangement by Share-based Payment Award
Compensation costs related to unvested outstanding stock options					$ 105,800		$ 105,800
Compensation costs related to unvested outstanding stock options, period for recognition (in years)							2 years 8 months 12 days
Class A Common Stock | 2021 Stock Option and Incentive Plan
Share-based Compensation Arrangement by Share-based Payment Award
Common stock reserved for future issuance (in shares)					60,000,000		60,000,000
Class A Common Stock | 2021 Stock Option and Incentive Plan | Forecast
Share-based Compensation Arrangement by Share-based Payment Award
Common stock reserved for future issuance, annual increase, percent									5.00%
Class A Common Stock | 2021 Employee Stock Purchase Plan
Share-based Compensation Arrangement by Share-based Payment Award
Common stock reserved for future issuance (in shares)					6,000,000		6,000,000
Purchase price of common stock, percent							85.00%
Class A Common Stock | 2021 Employee Stock Purchase Plan | Forecast
Share-based Compensation Arrangement by Share-based Payment Award
Common stock reserved for future issuance, annual increase, percent									1.00%
Common stock reserved for future issuance, annual share increase (in shares)									12,000,000
Class A Common Stock | Stock Options | 2011 Plan
Share-based Compensation Arrangement by Share-based Payment Award
Fair market value of one share of common stock threshold							110.00%
Combined voting power of stockholder, 10% Stockholder							10.00%
Expiration period (in years)							10 years
Class A Common Stock | Stock options, 10% Stockholders | 2011 Plan
Share-based Compensation Arrangement by Share-based Payment Award
Combined voting power of stockholder, 10% Stockholder							10.00%
Expiration period (in years)							5 years

Stock Incentive Plans - Summary

Stock Incentive Plans - Summary of Stock Option Activity Under Stock Incentive Plan (Details) - Stock Options - USD ($) $ / shares in Units, $ in Thousands	3 Months Ended	9 Months Ended
	Mar. 31, 2021	Sep. 30, 2021	Dec. 31, 2020
Number of Options
Balance at the beginning of the period (in shares)	23,421,374	23,421,374
Granted (in shares)		29,113,555
Exercised (in shares)		(3,236,786)
Canceled and forfeited (in shares)		(3,241,591)
Balance at the end of the period (in shares)		46,056,552
Weighted-Average Exercise Price per Share
Balance at the beginning of the period (in dollars per share)	$ 1.35	$ 1.35
Granted (in dollars per share)		20.07
Exercised (in dollars per share)		1.06
Canceled and forfeited (in dollars per share)		2.89
Balance at the end of the period (in dollars per share)		$ 13.09
Option Activity, Additional Disclosures
Options outstanding, Weighted Average Remaining Contractual Life (Years)	8 years 3 months 29 days	8 years 7 months 28 days
Options outstanding, Aggregate Intrinsic Value (in USD)		$ 417,075	$ 248,002
Options Vested as of September 30, 2021, Number of Options (in shares)		9,922,355
Options Vested as of September 30, 2021, Exercise Price per Share (in dollars per share)		$ 1.43
Options Vested, Weighted Average Remaining Contractual Life (Years)		6 years 8 months 23 days
Options Vested, as of September 30, 2021, Aggregate Intrinsic Value (in USD)		$ 219,482

Stock Incentive Plans - Weighte

Stock Incentive Plans - Weighted Average Assumptions (Details)	3 Months Ended		9 Months Ended
	Sep. 30, 2021	Sep. 30, 2020	Sep. 30, 2021	Sep. 30, 2020
Share-based Payment Arrangement [Abstract]
Dividend yield	0.00%	0.00%	0.00%	0.00%
Expected volatility	57.48%	49.93%	54.15%	48.11%
Expected term (in years)	6 years 29 days	6 years 7 days	6 years 8 months 23 days	6 years 7 days
Risk-free interest rate	1.18%	0.36%	1.22%	0.54%

Stock Incentive Plans - CEO Per

Stock Incentive Plans - CEO Performance Awards (Details) - CEO Long-Term Performance Award - Chief Executive Officer	9 Months Ended
	Sep. 30, 2021$ / sharesshares
Share-based Compensation Arrangement by Share-based Payment Award
Number of Options Eligible to Vest (in shares)	19,788,188
Tranche 1
Share-based Compensation Arrangement by Share-based Payment Award
Number of Options Eligible to Vest (in shares)	2,826,884
Company Stock Price Hurdle (in dollars per share) | $ / shares	$ 67.50
Tranche 2
Share-based Compensation Arrangement by Share-based Payment Award
Number of Options Eligible to Vest (in shares)	2,826,884
Company Stock Price Hurdle (in dollars per share) | $ / shares	$ 78.98
Tranche 3
Share-based Compensation Arrangement by Share-based Payment Award
Number of Options Eligible to Vest (in shares)	2,826,884
Company Stock Price Hurdle (in dollars per share) | $ / shares	$ 92.40
Tranche 4
Share-based Compensation Arrangement by Share-based Payment Award
Number of Options Eligible to Vest (in shares)	2,826,884
Company Stock Price Hurdle (in dollars per share) | $ / shares	$ 108.11
Tranche 5
Share-based Compensation Arrangement by Share-based Payment Award
Number of Options Eligible to Vest (in shares)	2,826,884
Company Stock Price Hurdle (in dollars per share) | $ / shares	$ 126.49
Tranche 6
Share-based Compensation Arrangement by Share-based Payment Award
Number of Options Eligible to Vest (in shares)	2,826,884
Company Stock Price Hurdle (in dollars per share) | $ / shares	$ 147.99
Tranche 7
Share-based Compensation Arrangement by Share-based Payment Award
Number of Options Eligible to Vest (in shares)	2,826,884
Company Stock Price Hurdle (in dollars per share) | $ / shares	$ 173.15

Stock Incentive Plans - Restric

Stock Incentive Plans - Restricted Stock Units (Details) - Restricted Stock Units (RSUs)	9 Months Ended
	Sep. 30, 2021$ / sharesshares
Number of Restricted Stock Units
Balance at beginning of the period (in shares) | shares	4,430,336
Granted (in shares) | shares	7,420,972
Vested (in shares) | shares	(1,985,645)
Canceled and forfeited (in shares) | shares	(649,478)
Balance at the end of the period (in shares) | shares	9,216,185
Weighted-average grant date fair value per share
Balance at the beginning of the period (in dollars per share) | $ / shares	$ 4.93
Grant (in dollars per share) | $ / shares	20.58
Vested (in dollars per share) | $ / shares	7.60
Canceled and forfeited (in dollars per share) | $ / shares	11.78
Balance at the end of the period (in dollars per share) | $ / shares	$ 15.85

Warrants to Purchase Common S_3

Warrants to Purchase Common Stock - Narrative (Details) $ / shares in Units, $ in Thousands	1 Months Ended	3 Months Ended			9 Months Ended
	Mar. 31, 2021USD ($)customer$ / sharesshares	Sep. 30, 2021USD ($)shares	Mar. 31, 2016warrant	Mar. 31, 2014warrant	Sep. 30, 2021USD ($)shares	Jul. 31, 2021shares	Dec. 31, 2020USD ($)$ / sharesshares	Dec. 31, 2016$ / sharesshares	Dec. 31, 2015$ / sharesshares	Dec. 31, 2014$ / sharesshares	Dec. 31, 2013$ / sharesshares
Class of Warrant or Right [Line Items]
Vested warrants outstanding (in shares)		183,334			183,334
Redeemable convertible preferred stock warrant liabilities | $		$ 0			$ 0		$ 2,517
Class of warrant or right, reduction to net revenues in the period | $		$ 2,000			$ 3,000
Number of customers | customer	2
Warrants contingent performance condition, measurement period (in years)	3 years
Class B Common Stock
Class of Warrant or Right [Line Items]
Number of securities called by each warrant (in shares)		668,412			668,412
Series B, Redeemable Convertible Preferred Stock Warrants
Class of Warrant or Right [Line Items]
Number of warrants | warrant				2
Number of securities called by each warrant (in shares)						203,610				101,805	101,805
Exercise price of warrants (in dollars per share) | $ / shares										$ 0.295	$ 0.295
Common Stock Warrants
Class of Warrant or Right [Line Items]
Number of warrants | warrant			2
Number of securities called by each warrant (in shares)							750,000
Exercise price of warrants (in dollars per share) | $ / shares	$ 0.01						$ 0.01	$ 0.053	$ 0.053
Vested warrants outstanding (in shares)		25,900			25,900
Warrant term (in years)	4 years						5 years
Redeemable convertible preferred stock warrant liabilities | $	$ 26,400						$ 5,700
Class of warrant or right, reduction to net revenues in the period | $		$ 100			$ 200
Common Stock Warrants | Customer One
Class of Warrant or Right [Line Items]
Number of securities called by each warrant (in shares)	1,100,000
Common Stock Warrants | Customer Two
Class of Warrant or Right [Line Items]
Number of securities called by each warrant (in shares)	50,000
2015 Common Stock Warrants
Class of Warrant or Right [Line Items]
Number of securities called by each warrant (in shares)									231,348
Vested warrants outstanding (in shares)							231,348
2016 Common Stock Warrants
Class of Warrant or Right [Line Items]
Number of securities called by each warrant (in shares)								621,066
Vested warrants outstanding (in shares)							438,180

Warrants to Purchase Common S_4

Warrants to Purchase Common Stock - Measurement Inputs (Details)	Sep. 30, 2021	Mar. 31, 2021	Dec. 31, 2020
Dividend yield
Class of Warrant or Right [Line Items]
Measurement input (percent)	0		0
Expected volatility
Class of Warrant or Right [Line Items]
Measurement input (percent)	0.4993		0.4993
Risk-free interest rate
Class of Warrant or Right [Line Items]
Measurement input (percent)	0.0031		0.0017
Common Stock Warrants
Class of Warrant or Right [Line Items]
Warrant term (in years)		4 years	5 years
September 2020 Common Stock Warrants
Class of Warrant or Right [Line Items]
Warrant term (in years)			5 years
September 2020 Common Stock Warrants | Dividend yield
Class of Warrant or Right [Line Items]
Measurement input (percent)			0
September 2020 Common Stock Warrants | Expected volatility
Class of Warrant or Right [Line Items]
Measurement input (percent)			0.500
September 2020 Common Stock Warrants | Risk-free interest rate
Class of Warrant or Right [Line Items]
Measurement input (percent)			0.003
March 2021 Common Stock Warrants
Class of Warrant or Right [Line Items]
Warrant term (in years)	4 years
March 2021 Common Stock Warrants | Dividend yield
Class of Warrant or Right [Line Items]
Measurement input (percent)	0
March 2021 Common Stock Warrants | Expected volatility
Class of Warrant or Right [Line Items]
Measurement input (percent)	0.500
March 2021 Common Stock Warrants | Risk-free interest rate
Class of Warrant or Right [Line Items]
Measurement input (percent)	0.006

Net Loss Per Share Attributab_3

Net Loss Per Share Attributable to Common Stockholders - EPS (Details) - USD ($) $ / shares in Units, $ in Thousands	3 Months Ended						9 Months Ended
	Sep. 30, 2021	Jun. 30, 2021	Mar. 31, 2021	Sep. 30, 2020	Jun. 30, 2020	Mar. 31, 2020	Sep. 30, 2021	Sep. 30, 2020
Earnings Per Share [Abstract]
Net loss	$ (45,730)	$ (68,554)	$ (12,838)	$ (12,298)	$ (7,107)	$ (14,530)	$ (127,122)	$ (33,935)
Weighted-average shares used in computing net loss per share attributable to common stockholders - Diluted (in shares)	538,896,513			124,225,475			302,967,155	120,931,681
Weighted-average shares used in computing net loss per share attributable to common stockholders - Basic (in shares)	538,896,513			124,225,475			302,967,155	120,931,681
Net loss per share attributable to common stockholders, basic (in dollars per share)	$ (0.08)			$ (0.10)			$ (0.42)	$ (0.28)
Net loss per share attributable to common stockholders, diluted (in dollars per share)	$ (0.08)			$ (0.10)			$ (0.42)	$ (0.28)

Net Loss Per Share Attributab_4

Net Loss Per Share Attributable to Common Stockholders - Antidilutive Securities (Details) - shares	9 Months Ended
	Sep. 30, 2021	Sep. 30, 2020
Antidilutive Securities Excluded from Computation of Earnings Per Share [Line Items]
Antidilutive securities excluded from computation of earnings per share, amount (in shares)	57,172,737	382,161,224
Redeemable convertible preferred stock, all series
Antidilutive Securities Excluded from Computation of Earnings Per Share [Line Items]
Antidilutive securities excluded from computation of earnings per share, amount (in shares)	0	351,844,340
Warrants to purchase redeemable convertible preferred stock
Antidilutive Securities Excluded from Computation of Earnings Per Share [Line Items]
Antidilutive securities excluded from computation of earnings per share, amount (in shares)	0	203,610
Warrants to purchase Class B common stock
Antidilutive Securities Excluded from Computation of Earnings Per Share [Line Items]
Antidilutive securities excluded from computation of earnings per share, amount (in shares)	1,900,000	1,419,528
Stock options outstanding, including early exercise of options
Antidilutive Securities Excluded from Computation of Earnings Per Share [Line Items]
Antidilutive securities excluded from computation of earnings per share, amount (in shares)	46,056,552	24,908,901
Unvested RSUs outstanding
Antidilutive Securities Excluded from Computation of Earnings Per Share [Line Items]
Antidilutive securities excluded from computation of earnings per share, amount (in shares)	9,216,185	3,784,845

Income Taxes (Details)

Income Taxes (Details)	3 Months Ended		9 Months Ended
	Sep. 30, 2021	Sep. 30, 2020	Sep. 30, 2021	Sep. 30, 2020
Income Tax Contingency [Line Items]
Effective income tax rate reconciliation percent		0.00%
Domestic Tax Authority
Income Tax Contingency [Line Items]
Effective income tax rate reconciliation percent	0.00%		0.00%	0.00%

Concentration of Risks and Si_2

Concentration of Risks and Significant Customers (Details) $ in Thousands	3 Months Ended			9 Months Ended
	Sep. 30, 2021USD ($)investment	Mar. 31, 2021	Sep. 30, 2020USD ($)	Sep. 30, 2021USD ($)investment	Sep. 30, 2020USD ($)	Dec. 31, 2020USD ($)
Concentration Risk [Line Items]
Cash and cash equivalents	$ 1,260,220		$ 214,960	$ 1,260,220	$ 214,960	$ 220,433
Marketable securities	408,954			408,954		149,903
Credit Concentration Risk | Investments
Concentration Risk [Line Items]
Cash and cash equivalents	$ 1,200,000			$ 1,200,000		203,600
Number of investments | investment	3			3
Credit Concentration Risk | Debt Securities, Available-For-Sale
Concentration Risk [Line Items]
Marketable securities	$ 374,600			$ 374,600		$ 125,900
Credit Concentration Risk | Debt Securities, Available-For-Sale | Marketable Securities
Concentration Risk [Line Items]
Concentration risk, percentage		84.00%		92.00%
Credit Concentration Risk | Accounts Receivable | Sutton Bank
Concentration Risk [Line Items]
Concentration risk, percentage	89.00%		96.00%	92.00%	96.00%
Customer Concentration Risk | Revenue from Contract with Customer Benchmark | Largest customer
Concentration Risk [Line Items]
Concentration risk, percentage	68.00%		72.00%	71.00%	69.00%
Customer Concentration Risk | Revenue from Contract with Customer Benchmark | Second largest customer
Concentration Risk [Line Items]
Concentration risk, percentage			9.00%		11.00%

Related Party Transactions (Det

Related Party Transactions (Details) - USD ($) $ in Millions	3 Months Ended	9 Months Ended
	Sep. 30, 2020	Sep. 30, 2020	May 31, 2021
DFS Services LLC | DFS Services LLC | DFS Services LLC
Related Party Transaction [Line Items]
Ownership interest by related party			5.00%
PULSE Network LLC | Card Network Fees, Net
Related Party Transaction [Line Items]
Expenses from transactions with related parties	$ 9.3	$ 21.4